Bump version to 0.22.0 (#1500)

There are two PRs I'm aware of that should be relatively trivial to get
merged, which would fix some issues. Other than those, I don't think it
makes sense to wait on anything.

 - Fix Windows crash: https://github.com/rust-windowing/winit/pull/1459
 - Fix macOS mouse reports: https://github.com/rust-windowing/winit/pull/1490

While #1459 seems pretty essential to actually make winit run, #1490 is
much less important and can probably be ignored if there aren't any
resources to merge it.

.github/workflows/ci.yml

@@ -0,0 +1,106 @@
+name: CI
+
+on:
+  pull_request:
+    paths:
+      - '**.rs'
+      - '**.toml'
+      - '.github/workflows/ci.yml'
+  push:
+    branches: [master]
+    paths:
+      - '**.rs'
+      - '**.toml'
+      - '.github/workflows/ci.yml'
+
+jobs:
+  Check_Formatting:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: hecrj/setup-rust-action@v1
+      with:
+        rust-version: stable
+        components: rustfmt
+    - name: Check Formatting
+      run: cargo +stable fmt --all -- --check
+
+  Tests:
+    strategy:
+      fail-fast: false
+      matrix:
+        rust_version: [stable, nightly]
+        platform:
+          - { target: x86_64-pc-windows-msvc,   os: windows-latest,  }
+          - { target: i686-pc-windows-msvc,     os: windows-latest,  }
+          - { target: x86_64-pc-windows-gnu,    os: windows-latest, host: -x86_64-pc-windows-gnu }
+          - { target: i686-pc-windows-gnu,      os: windows-latest, host: -i686-pc-windows-gnu }
+          - { target: i686-unknown-linux-gnu,   os: ubuntu-latest,   }
+          - { target: x86_64-unknown-linux-gnu, os: ubuntu-latest,   }
+          - { target: x86_64-apple-darwin,      os: macos-latest,    }
+          - { target: x86_64-apple-ios,         os: macos-latest,    }
+          - { target: aarch64-apple-ios,        os: macos-latest,    }
+          # We're using Windows rather than Ubuntu to run the wasm tests because caching cargo-web
+          # doesn't currently work on Linux.
+          - { target: wasm32-unknown-unknown,   os: windows-latest, features: stdweb,  web: web }
+          - { target: wasm32-unknown-unknown,   os: windows-latest, features: web-sys, web: web }
+
+    env:
+      RUST_BACKTRACE: 1
+      CARGO_INCREMENTAL: 0
+      RUSTFLAGS: "-C debuginfo=0"
+      FEATURES: ${{ format(',{0}', matrix.platform.features ) }}
+      WEB: ${{ matrix.platform.web }}
+
+    runs-on: ${{ matrix.platform.os }}
+    steps:
+    - uses: actions/checkout@v2
+    # Used to cache cargo-web
+    - name: Cache cargo folder
+      uses: actions/cache@v1
+      with:
+        path: ~/.cargo
+        key: ${{ matrix.platform.target }}-cargo-${{ matrix.rust_version }}
+
+    - uses: hecrj/setup-rust-action@v1
+      with:
+        rust-version: ${{ matrix.rust_version }}${{ matrix.platform.host }}
+        targets: ${{ matrix.platform.target }}
+
+    - name: Install GCC Multilib
+      if: (matrix.platform.os == 'ubuntu-latest') && contains(matrix.platform.target, 'i686')
+      run: sudo apt-get update && sudo apt-get install gcc-multilib
+    - name: Install cargo-web
+      continue-on-error: true
+      if: contains(matrix.platform.target, 'wasm32')
+      run: cargo install cargo-web
+
+    - name: Check documentation
+      shell: bash
+      if: matrix.platform.target != 'wasm32-unknown-unknown'
+      run: cargo doc --no-deps --target ${{ matrix.platform.target }} --features $FEATURES
+
+    - name: Build
+      shell: bash
+      run: cargo $WEB build --verbose --target ${{ matrix.platform.target }} --features $FEATURES
+
+    - name: Build tests
+      shell: bash
+      run: cargo $WEB test --no-run --verbose --target ${{ matrix.platform.target }} --features $FEATURES
+    - name: Run tests
+      shell: bash
+      if: (!contains(matrix.platform.target, 'ios') && !contains(matrix.platform.target, 'wasm32'))
+      run: cargo $WEB test --verbose --target ${{ matrix.platform.target }} --features $FEATURES
+
+
+    - name: Build with serde enabled
+      shell: bash
+      run: cargo $WEB build --verbose --target ${{ matrix.platform.target }} --features serde,$FEATURES
+
+    - name: Build tests with serde enabled
+      shell: bash
+      run: cargo $WEB test --no-run --verbose --target ${{ matrix.platform.target }} --features serde,$FEATURES
+    - name: Run tests with serde enabled
+      shell: bash
+      if: (!contains(matrix.platform.target, 'ios') && !contains(matrix.platform.target, 'wasm32'))
+      run: cargo $WEB test --verbose --target ${{ matrix.platform.target }} --features serde,$FEATURES

.github/workflows/publish.yml

@@ -0,0 +1,18 @@
+name: Publish
+
+on:
+  push:
+    branches: [master]
+    paths: "Cargo.toml"
+
+jobs:
+  Publish:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: hecrj/setup-rust-action@v1
+      with:
+        rust-version: stable
+        components: rustfmt
+    - name: Publish to crates.io
+      run: cargo publish --token ${{ secrets.cratesio_token }}

.gitignore

@@ -2,7 +2,6 @@ Cargo.lock
 target/
 rls/
 .vscode/
-util/
 *~
 *.wasm
 *.ts

.travis.yml

@@ -1,104 +0,0 @@
-language: rust
-
-matrix:
-  include:
-    # Linux 32bit
-    - env: TARGET=i686-unknown-linux-gnu
-      os: linux
-      rust: nightly
-      addons:
-        apt:
-          # Cross compiler and cross compiled C libraries
-          packages: &i686_packages
-            - gcc-multilib
-    - env: TARGET=i686-unknown-linux-gnu
-      os: linux
-      rust: stable
-      addons:
-        apt:
-          packages: *i686_packages
-
-    # Linux 64bit
-    - env: TARGET=x86_64-unknown-linux-gnu
-      os: linux
-      rust: nightly
-    - env: TARGET=x86_64-unknown-linux-gnu
-      os: linux
-      rust: stable
-
-    # macOS
-    - env: TARGET=x86_64-apple-darwin
-      os: osx
-      rust: nightly
-    - env: TARGET=x86_64-apple-darwin
-      os: osx
-      rust: stable
-
-    # iOS x86_64
-    - env: TARGET=x86_64-apple-ios
-      os: osx
-      rust: nightly
-    - env: TARGET=x86_64-apple-ios
-      os: osx
-      rust: stable
-
-    # iOS armv7
-    - env: TARGET=armv7-apple-ios
-      os: osx
-      rust: nightly
-    - env: TARGET=armv7-apple-ios
-      os: osx
-      rust: stable
-
-    # iOS arm64
-    - env: TARGET=aarch64-apple-ios
-      os: osx
-      rust: nightly
-    - env: TARGET=aarch64-apple-ios
-      os: osx
-      rust: stable
-
-    # wasm stdweb
-    - env: TARGET=wasm32-unknown-unknown WEB=web FEATURES=stdweb
-      os: linux
-      rust: stable
-    - env: TARGET=wasm32-unknown-unknown WEB=web FEATURES=stdweb
-      os: linux
-      rust: nightly
-    # wasm web-sys
-    - env: TARGET=wasm32-unknown-unknown FEATURES=web-sys
-      os: linux
-      rust: stable
-    - env: TARGET=wasm32-unknown-unknown FEATURES=web-sys
-      os: linux
-      rust: nightly
-
-install:
-  - rustup self update
-  - rustup target add $TARGET; true
-  - rustup toolchain install stable
-  - rustup component add rustfmt --toolchain stable
-
-script:
-  - cargo +stable fmt --all -- --check
-  # Ensure that the documentation builds properly.
-  - cargo doc --no-deps
-  # Install cargo-web to build stdweb
-  - if [[ $WEB = "web" ]]; then cargo install -f cargo-web; fi
-  # Build without serde then with serde
-  - if [[ -z "$FEATURES" ]]; then
-      cargo $WEB build --target $TARGET --verbose;
-    else
-      cargo $WEB build --target $TARGET --features $FEATURES --verbose;
-    fi
-  - cargo $WEB build --target $TARGET --features serde,$FEATURES --verbose
-  # Running iOS apps on macOS requires the Simulator so we skip that for now
-  # The web targets also don't support running tests
-  - if [[ $TARGET != *-apple-ios && $TARGET != wasm32-* ]]; then cargo test --target $TARGET --verbose; fi
-  - if [[ $TARGET != *-apple-ios && $TARGET != wasm32-* ]]; then cargo test --target $TARGET --features serde --verbose; fi
-
-after_success:
-  - |
-      [ $TRAVIS_BRANCH = master ] &&
-      [ $TRAVIS_PULL_REQUEST = false ] &&
-      cargo publish --token ${CRATESIO_TOKEN}

CHANGELOG.md

@@ -1,4 +1,52 @@
-# Unreleased
+# 0.22.0 (2020-03-07)
+
+- On Windows, fix minor timing issue in wait_until_time_or_msg
+- On Windows, rework handling of request_redraw() to address panics.
+- On macOS, fix `set_simple_screen` to remember frame excluding title bar.
+- On Wayland, fix coordinates in touch events when scale factor isn't 1.
+- On Wayland, fix color from `close_button_icon_color` not applying.
+- Ignore locale if unsupported by X11 backend
+- On Wayland, Add HiDPI cursor support
+- On Web, add the ability to query "Light" or "Dark" system theme send `ThemeChanged` on change.
+- Fix `Event::to_static` returning `None` for user events.
+- On Wayland, Hide CSD for fullscreen windows.
+- On Windows, ignore spurious mouse move messages.
+- **Breaking:** Move `ModifiersChanged` variant from `DeviceEvent` to `WindowEvent`.
+- On Windows, add `IconExtWindows` trait which exposes creating an `Icon` from an external file or embedded resource
+- Add `BadIcon::OsError` variant for when OS icon functionality fails
+- On Windows, fix crash at startup on systems that do not properly support Windows' Dark Mode
+- Revert On macOS, fix not sending ReceivedCharacter event for specific keys combinations.
+- on macOS, fix incorrect ReceivedCharacter events for some key combinations.
+- **Breaking:** Use `i32` instead of `u32` for position type in `WindowEvent::Moved`.
+
+# 0.21.0 (2020-02-04)
+
+- On Windows, fixed "error: linking with `link.exe` failed: exit code: 1120" error on older versions of windows.
+- On macOS, fix set_minimized(true) works only with decorations.
+- On macOS, add `hide_application` to `EventLoopWindowTarget` via a new `EventLoopWindowTargetExtMacOS` trait. `hide_application` will hide the entire application by calling `-[NSApplication hide: nil]`.
+- On macOS, fix not sending ReceivedCharacter event for specific keys combinations.
+- On macOS, fix `CursorMoved` event reporting the cursor position using logical coordinates.
+- On macOS, fix issue where unbundled applications would sometimes open without being focused.
+- On macOS, fix `run_return` does not return unless it receives a message.
+- On Windows, fix bug where `RedrawRequested` would only get emitted every other iteration of the event loop.
+- On X11, fix deadlock on window state when handling certain window events.
+- `WindowBuilder` now implements `Default`.
+- **Breaking:** `WindowEvent::CursorMoved` changed to `f64` units, preserving high-precision data supplied by most backends
+- On Wayland, fix coordinates in mouse events when scale factor isn't 1
+- On Web, add the ability to provide a custom canvas
+- **Breaking:** On Wayland, the `WaylandTheme` struct has been replaced with a `Theme` trait, allowing for extra configuration
+
+# 0.20.0 (2020-01-05)
+
+- On X11, fix `ModifiersChanged` emitting incorrect modifier change events
+- **Breaking**: Overhaul how Winit handles DPI:
+  + Window functions and events now return `PhysicalSize` instead of `LogicalSize`.
+  + Functions that take `Size` or `Position` types can now take either `Logical` or `Physical` types.
+  + `hidpi_factor` has been renamed to `scale_factor`.
+  + `HiDpiFactorChanged` has been renamed to `ScaleFactorChanged`, and lets you control how the OS
+    resizes the window in response to the change.
+  + On X11, deprecate `WINIT_HIDPI_FACTOR` environment variable in favor of `WINIT_X11_SCALE_FACTOR`.
+  + `Size` and `Position` types are now generic over their exact pixel type.
 
 # 0.20.0 Alpha 6 (2020-01-03)
 
@@ -8,7 +56,7 @@
 - On all platforms except mobile and WASM, implement `Window::set_minimized`.
 - On X11, fix `CursorEntered` event being generated for non-winit windows.
 - On macOS, fix crash when starting maximized without decorations.
-- On macOS, fix application not to terminate on `run_return`.
+- On macOS, fix application not terminating on `run_return`.
 - On Wayland, fix cursor icon updates on window borders when using CSD.
 - On Wayland, under mutter(GNOME Wayland), fix CSD being behind the status bar, when starting window in maximized mode.
 - On Windows, theme the title bar according to whether the system theme is "Light" or "Dark".
@@ -89,6 +137,7 @@
     reduces the potential for cross-platform compatibility gotchyas.
 - On Windows and Linux X11/Wayland, add platform-specific functions for creating an `EventLoop` outside the main thread.
 - On Wayland, drop resize events identical to the current window size.
+- On Windows, fix window rectangle not getting set correctly on high-DPI systems.
 
 # 0.20.0 Alpha 3 (2019-08-14)
 

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "winit"
-version = "0.20.0-alpha6"
+version = "0.22.0"
 authors = ["The winit contributors", "Pierre Krieger <pierre.krieger1708@gmail.com>"]
 description = "Cross-platform window creation library."
 edition = "2018"
@@ -28,8 +28,8 @@ raw-window-handle = "0.3"
 bitflags = "1"
 
 [dev-dependencies]
-image = "0.21"
-env_logger = "0.5"
+image = "0.23"
+simple_logger = "1"
 
 [target.'cfg(target_os = "android")'.dependencies.android_glue]
 version = "0.2"
@@ -41,8 +41,8 @@ objc = "0.2.3"
 cocoa = "0.19.1"
 core-foundation = "0.6"
 core-graphics = "0.17.3"
-dispatch = "0.1.4"
-objc = "0.2.3"
+dispatch = "0.2.0"
+objc = "0.2.6"
 
 [target.'cfg(target_os = "macos")'.dependencies.core-video-sys]
 version = "0.1.3"
@@ -75,8 +75,9 @@ features = [
 
 [target.'cfg(any(target_os = "linux", target_os = "dragonfly", target_os = "freebsd", target_os = "openbsd", target_os = "netbsd"))'.dependencies]
 wayland-client = { version = "0.23.0", features = [ "dlopen", "egl", "cursor", "eventloop"] }
-calloop = "0.4.2"
-smithay-client-toolkit = "0.6"
+mio = "0.6"
+mio-extras = "2.0"
+smithay-client-toolkit = "^0.6.6"
 x11-dl = "2.18.3"
 percent-encoding = "2.0"
 
@@ -89,6 +90,7 @@ version = "0.3.22"
 optional = true
 features = [
     'console',
+    'CssStyleDeclaration',
     'BeforeUnloadEvent',
     'Document',
     'DomRect',
@@ -99,6 +101,8 @@ features = [
     'HtmlCanvasElement',
     'HtmlElement',
     'KeyboardEvent',
+    'MediaQueryList',
+    'MediaQueryListEvent',
     'MouseEvent',
     'Node',
     'PointerEvent',

FEATURES.md

@@ -149,6 +149,9 @@ If your PR makes notable changes to Winit's features, please update this section
 * Getting the device idiom
 * Getting the preferred video mode
 
+### Web
+* Get if systems preferred color scheme is "dark"
+
 ## Usability
 * `serde`: Enables serialization/deserialization of certain types with Serde. (Maintainer: @Osspial)
 

README.md

@@ -7,7 +7,7 @@
 
 ```toml
 [dependencies]
-winit = "0.20.0-alpha6"
+winit = "0.22.0"
 ```
 
 ## [Documentation](https://docs.rs/winit)
@@ -46,12 +46,14 @@ fn main() {
     let window = WindowBuilder::new().build(&event_loop).unwrap();
 
     event_loop.run(move |event, _, control_flow| {
+        *control_flow = ControlFlow::Wait;
+
         match event {
             Event::WindowEvent {
                 event: WindowEvent::CloseRequested,
                 window_id,
             } if window_id == window.id() => *control_flow = ControlFlow::Exit,
-            _ => *control_flow = ControlFlow::Wait,
+            _ => (),
         }
     });
 }

appveyor.yml

@@ -1,35 +0,0 @@
-environment:
-  matrix:
-  - TARGET: x86_64-pc-windows-msvc
-    CHANNEL: stable
-  - TARGET: i686-pc-windows-msvc
-    CHANNEL: stable
-  - TARGET: x86_64-pc-windows-gnu
-    CHANNEL: stable
-  - TARGET: i686-pc-windows-gnu
-    CHANNEL: stable
-  - TARGET: x86_64-pc-windows-msvc
-    CHANNEL: nightly
-  - TARGET: i686-pc-windows-msvc
-    CHANNEL: nightly
-  - TARGET: x86_64-pc-windows-gnu
-    CHANNEL: nightly
-  - TARGET: i686-pc-windows-gnu
-    CHANNEL: nightly
-matrix:
-  allow_failures:
-    - CHANNEL: nightly
-install:
-  - appveyor DownloadFile https://win.rustup.rs/ -FileName rustup-init.exe
-  - rustup-init -yv --default-toolchain %CHANNEL% --default-host %TARGET%
-  - SET PATH=%PATH%;%USERPROFILE%\.cargo\bin
-  - SET PATH=%PATH%;C:\MinGW\bin
-  - rustc -V
-  - cargo -V
-
-build: false
-
-test_script:
-  - cargo test --verbose
-  - cargo test --features serde --verbose
-  - cargo doc --no-deps

examples/control_flow.rs

@@ -0,0 +1,119 @@
+use std::{thread, time};
+
+use winit::{
+    event::{Event, KeyboardInput, WindowEvent},
+    event_loop::{ControlFlow, EventLoop},
+    window::WindowBuilder,
+};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum Mode {
+    Wait,
+    WaitUntil,
+    Poll,
+}
+
+const WAIT_TIME: time::Duration = time::Duration::from_millis(100);
+const POLL_SLEEP_TIME: time::Duration = time::Duration::from_millis(100);
+
+fn main() {
+    simple_logger::init().unwrap();
+
+    println!("Press '1' to switch to Wait mode.");
+    println!("Press '2' to switch to WaitUntil mode.");
+    println!("Press '3' to switch to Poll mode.");
+    println!("Press 'R' to toggle request_redraw() calls.");
+    println!("Press 'Esc' to close the window.");
+
+    let event_loop = EventLoop::new();
+    let window = WindowBuilder::new()
+        .with_title("Press 1, 2, 3 to change control flow mode. Press R to toggle redraw requests.")
+        .build(&event_loop)
+        .unwrap();
+
+    let mut mode = Mode::Wait;
+    let mut request_redraw = false;
+    let mut wait_cancelled = false;
+    let mut close_requested = false;
+
+    event_loop.run(move |event, _, control_flow| {
+        use winit::event::{ElementState, StartCause, VirtualKeyCode};
+        println!("{:?}", event);
+        match event {
+            Event::NewEvents(start_cause) => {
+                wait_cancelled = mode == Mode::WaitUntil;
+                match start_cause {
+                    StartCause::ResumeTimeReached {
+                        start: _,
+                        requested_resume: _,
+                    } => {
+                        wait_cancelled = false;
+                    }
+                    _ => (),
+                }
+            }
+            Event::WindowEvent { event, .. } => match event {
+                WindowEvent::CloseRequested => {
+                    close_requested = true;
+                }
+                WindowEvent::KeyboardInput {
+                    input:
+                        KeyboardInput {
+                            virtual_keycode: Some(virtual_code),
+                            state: ElementState::Pressed,
+                            ..
+                        },
+                    ..
+                } => match virtual_code {
+                    VirtualKeyCode::Key1 => {
+                        mode = Mode::Wait;
+                        println!("\nmode: {:?}\n", mode);
+                    }
+                    VirtualKeyCode::Key2 => {
+                        mode = Mode::WaitUntil;
+                        println!("\nmode: {:?}\n", mode);
+                    }
+                    VirtualKeyCode::Key3 => {
+                        mode = Mode::Poll;
+                        println!("\nmode: {:?}\n", mode);
+                    }
+                    VirtualKeyCode::R => {
+                        request_redraw = !request_redraw;
+                        println!("\nrequest_redraw: {}\n", request_redraw);
+                    }
+                    VirtualKeyCode::Escape => {
+                        close_requested = true;
+                    }
+                    _ => (),
+                },
+                _ => (),
+            },
+            Event::MainEventsCleared => {
+                if request_redraw && !wait_cancelled && !close_requested {
+                    window.request_redraw();
+                }
+                if close_requested {
+                    *control_flow = ControlFlow::Exit;
+                }
+            }
+            Event::RedrawRequested(_window_id) => {}
+            Event::RedrawEventsCleared => {
+                *control_flow = match mode {
+                    Mode::Wait => ControlFlow::Wait,
+                    Mode::WaitUntil => {
+                        if wait_cancelled {
+                            *control_flow
+                        } else {
+                            ControlFlow::WaitUntil(time::Instant::now() + WAIT_TIME)
+                        }
+                    }
+                    Mode::Poll => {
+                        thread::sleep(POLL_SLEEP_TIME);
+                        ControlFlow::Poll
+                    }
+                };
+            }
+            _ => (),
+        }
+    });
+}

examples/cursor.rs

@@ -5,6 +5,7 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let window = WindowBuilder::new().build(&event_loop).unwrap();
@@ -12,35 +13,39 @@ fn main() {
 
     let mut cursor_idx = 0;
 
-    event_loop.run(move |event, _, control_flow| match event {
-        Event::WindowEvent {
-            event:
-                WindowEvent::KeyboardInput {
-                    input:
-                        KeyboardInput {
-                            state: ElementState::Pressed,
-                            ..
-                        },
-                    ..
-                },
-            ..
-        } => {
-            println!("Setting cursor to \"{:?}\"", CURSORS[cursor_idx]);
-            window.set_cursor_icon(CURSORS[cursor_idx]);
-            if cursor_idx < CURSORS.len() - 1 {
-                cursor_idx += 1;
-            } else {
-                cursor_idx = 0;
+    event_loop.run(move |event, _, control_flow| {
+        *control_flow = ControlFlow::Wait;
+
+        match event {
+            Event::WindowEvent {
+                event:
+                    WindowEvent::KeyboardInput {
+                        input:
+                            KeyboardInput {
+                                state: ElementState::Pressed,
+                                ..
+                            },
+                        ..
+                    },
+                ..
+            } => {
+                println!("Setting cursor to \"{:?}\"", CURSORS[cursor_idx]);
+                window.set_cursor_icon(CURSORS[cursor_idx]);
+                if cursor_idx < CURSORS.len() - 1 {
+                    cursor_idx += 1;
+                } else {
+                    cursor_idx = 0;
+                }
             }
+            Event::WindowEvent {
+                event: WindowEvent::CloseRequested,
+                ..
+            } => {
+                *control_flow = ControlFlow::Exit;
+                return;
+            }
+            _ => (),
         }
-        Event::WindowEvent {
-            event: WindowEvent::CloseRequested,
-            ..
-        } => {
-            *control_flow = ControlFlow::Exit;
-            return;
-        }
-        _ => (),
     });
 }
 

examples/cursor_grab.rs

@@ -5,6 +5,7 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let window = WindowBuilder::new()
@@ -16,6 +17,7 @@ fn main() {
 
     event_loop.run(move |event, _, control_flow| {
         *control_flow = ControlFlow::Wait;
+
         match event {
             Event::WindowEvent { event, .. } => match event {
                 WindowEvent::CloseRequested => *control_flow = ControlFlow::Exit,
@@ -36,6 +38,7 @@ fn main() {
                         _ => (),
                     }
                 }
+                WindowEvent::ModifiersChanged(m) => modifiers = m,
                 _ => (),
             },
             Event::DeviceEvent { event, .. } => match event {
@@ -44,7 +47,6 @@ fn main() {
                     ElementState::Pressed => println!("mouse button {} pressed", button),
                     ElementState::Released => println!("mouse button {} released", button),
                 },
-                DeviceEvent::ModifiersChanged(m) => modifiers = m,
                 _ => (),
             },
             _ => (),

examples/custom_events.rs

@@ -11,6 +11,7 @@ fn main() {
         Timer,
     }
 
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::<CustomEvent>::with_user_event();
 
     let _window = WindowBuilder::new()
@@ -31,13 +32,17 @@ fn main() {
         }
     });
 
-    event_loop.run(move |event, _, control_flow| match event {
-        Event::UserEvent(event) => println!("user event: {:?}", event),
-        Event::WindowEvent {
-            event: WindowEvent::CloseRequested,
-            ..
-        } => *control_flow = ControlFlow::Exit,
-        _ => *control_flow = ControlFlow::Wait,
+    event_loop.run(move |event, _, control_flow| {
+        *control_flow = ControlFlow::Wait;
+
+        match event {
+            Event::UserEvent(event) => println!("user event: {:?}", event),
+            Event::WindowEvent {
+                event: WindowEvent::CloseRequested,
+                ..
+            } => *control_flow = ControlFlow::Exit,
+            _ => (),
+        }
     });
 }
 

examples/fullscreen.rs

@@ -5,6 +5,7 @@ use winit::monitor::{MonitorHandle, VideoMode};
 use winit::window::{Fullscreen, WindowBuilder};
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     print!("Please choose the fullscreen mode: (1) exclusive, (2) borderless: ");

examples/handling_close.rs

@@ -5,6 +5,7 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let _window = WindowBuilder::new()

examples/min_max_size.rs

@@ -6,6 +6,7 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let window = WindowBuilder::new().build(&event_loop).unwrap();
@@ -14,6 +15,7 @@ fn main() {
     window.set_max_inner_size(Some(LogicalSize::new(800.0, 400.0)));
 
     event_loop.run(move |event, _, control_flow| {
+        *control_flow = ControlFlow::Wait;
         println!("{:?}", event);
 
         match event {
@@ -21,7 +23,7 @@ fn main() {
                 event: WindowEvent::CloseRequested,
                 ..
             } => *control_flow = ControlFlow::Exit,
-            _ => *control_flow = ControlFlow::Wait,
+            _ => (),
         }
     });
 }

examples/minimize.rs

@@ -5,6 +5,7 @@ use winit::event_loop::{ControlFlow, EventLoop};
 use winit::window::WindowBuilder;
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let window = WindowBuilder::new()
@@ -12,24 +13,28 @@ fn main() {
         .build(&event_loop)
         .unwrap();
 
-    event_loop.run(move |event, _, control_flow| match event {
-        Event::WindowEvent {
-            event: WindowEvent::CloseRequested,
-            ..
-        } => *control_flow = ControlFlow::Exit,
+    event_loop.run(move |event, _, control_flow| {
+        *control_flow = ControlFlow::Wait;
 
-        // Keyboard input event to handle minimize via a hotkey
-        Event::WindowEvent {
-            event: WindowEvent::KeyboardInput { input, .. },
-            window_id,
-        } => {
-            if window_id == window.id() {
-                // Pressing the 'M' key will minimize the window
-                if input.virtual_keycode == Some(VirtualKeyCode::M) {
-                    window.set_minimized(true);
+        match event {
+            Event::WindowEvent {
+                event: WindowEvent::CloseRequested,
+                ..
+            } => *control_flow = ControlFlow::Exit,
+
+            // Keyboard input event to handle minimize via a hotkey
+            Event::WindowEvent {
+                event: WindowEvent::KeyboardInput { input, .. },
+                window_id,
+            } => {
+                if window_id == window.id() {
+                    // Pressing the 'M' key will minimize the window
+                    if input.virtual_keycode == Some(VirtualKeyCode::M) {
+                        window.set_minimized(true);
+                    }
                 }
             }
+            _ => (),
         }
-        _ => *control_flow = ControlFlow::Wait,
     });
 }

examples/monitor_list.rs

@@ -1,6 +1,7 @@
 use winit::{event_loop::EventLoop, window::WindowBuilder};
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
     let window = WindowBuilder::new().build(&event_loop).unwrap();
 

examples/multithreaded.rs

@@ -1,24 +1,23 @@
 #[cfg(not(target_arch = "wasm32"))]
 fn main() {
-    extern crate env_logger;
-
     use std::{collections::HashMap, sync::mpsc, thread, time::Duration};
 
     use winit::{
+        dpi::{PhysicalPosition, PhysicalSize, Position, Size},
         event::{ElementState, Event, KeyboardInput, VirtualKeyCode, WindowEvent},
         event_loop::{ControlFlow, EventLoop},
         window::{CursorIcon, Fullscreen, WindowBuilder},
     };
 
     const WINDOW_COUNT: usize = 3;
-    const WINDOW_SIZE: (u32, u32) = (600, 400);
+    const WINDOW_SIZE: PhysicalSize<u32> = PhysicalSize::new(600, 400);
 
-    env_logger::init();
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
     let mut window_senders = HashMap::with_capacity(WINDOW_COUNT);
     for _ in 0..WINDOW_COUNT {
         let window = WindowBuilder::new()
-            .with_inner_size(WINDOW_SIZE.into())
+            .with_inner_size(WINDOW_SIZE)
             .build(&event_loop)
             .unwrap();
 
@@ -49,6 +48,7 @@ fn main() {
                             );
                         }
                     }
+                    #[allow(deprecated)]
                     WindowEvent::KeyboardInput {
                         input:
                             KeyboardInput {
@@ -101,31 +101,38 @@ fn main() {
                                 println!("-> fullscreen     : {:?}", window.fullscreen());
                             }
                             L => window.set_min_inner_size(match state {
-                                true => Some(WINDOW_SIZE.into()),
+                                true => Some(WINDOW_SIZE),
                                 false => None,
                             }),
                             M => window.set_maximized(state),
                             P => window.set_outer_position({
                                 let mut position = window.outer_position().unwrap();
-                                let sign = if state { 1.0 } else { -1.0 };
-                                position.x += 10.0 * sign;
-                                position.y += 10.0 * sign;
+                                let sign = if state { 1 } else { -1 };
+                                position.x += 10 * sign;
+                                position.y += 10 * sign;
                                 position
                             }),
                             Q => window.request_redraw(),
                             R => window.set_resizable(state),
-                            S => window.set_inner_size(
-                                match state {
-                                    true => (WINDOW_SIZE.0 + 100, WINDOW_SIZE.1 + 100),
-                                    false => WINDOW_SIZE,
+                            S => window.set_inner_size(match state {
+                                true => PhysicalSize::new(
+                                    WINDOW_SIZE.width + 100,
+                                    WINDOW_SIZE.height + 100,
+                                ),
+                                false => WINDOW_SIZE,
+                            }),
+                            W => {
+                                if let Size::Physical(size) = WINDOW_SIZE.into() {
+                                    window
+                                        .set_cursor_position(Position::Physical(
+                                            PhysicalPosition::new(
+                                                size.width as i32 / 2,
+                                                size.height as i32 / 2,
+                                            ),
+                                        ))
+                                        .unwrap()
                                 }
-                                .into(),
-                            ),
-                            W => window
-                                .set_cursor_position(
-                                    (WINDOW_SIZE.0 as i32 / 2, WINDOW_SIZE.1 as i32 / 2).into(),
-                                )
-                                .unwrap(),
+                            }
                             Z => {
                                 window.set_visible(false);
                                 thread::sleep(Duration::from_secs(1));
@@ -161,7 +168,9 @@ fn main() {
                 }
                 _ => {
                     if let Some(tx) = window_senders.get(&window_id) {
-                        tx.send(event).unwrap();
+                        if let Some(event) = event.to_static() {
+                            tx.send(event).unwrap();
+                        }
                     }
                 }
             },

examples/multiwindow.rs

@@ -6,6 +6,7 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let mut windows = HashMap::new();
@@ -16,6 +17,7 @@ fn main() {
 
     event_loop.run(move |event, event_loop, control_flow| {
         *control_flow = ControlFlow::Wait;
+
         match event {
             Event::WindowEvent { event, window_id } => {
                 match event {

examples/request_redraw.rs

@@ -1,13 +1,11 @@
-use instant::Instant;
-use std::time::Duration;
-
 use winit::{
-    event::{Event, WindowEvent},
+    event::{ElementState, Event, WindowEvent},
     event_loop::{ControlFlow, EventLoop},
     window::WindowBuilder,
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let window = WindowBuilder::new()
@@ -15,18 +13,26 @@ fn main() {
         .build(&event_loop)
         .unwrap();
 
-    event_loop.run(move |event, _, control_flow| match event {
-        Event::WindowEvent {
-            event: WindowEvent::CloseRequested,
-            ..
-        } => *control_flow = ControlFlow::Exit,
-        Event::MainEventsCleared => {
-            window.request_redraw();
-            *control_flow = ControlFlow::WaitUntil(Instant::now() + Duration::new(1, 0))
+    event_loop.run(move |event, _, control_flow| {
+        println!("{:?}", event);
+
+        *control_flow = ControlFlow::Wait;
+
+        match event {
+            Event::WindowEvent { event, .. } => match event {
+                WindowEvent::CloseRequested => *control_flow = ControlFlow::Exit,
+                WindowEvent::MouseInput {
+                    state: ElementState::Released,
+                    ..
+                } => {
+                    window.request_redraw();
+                }
+                _ => (),
+            },
+            Event::RedrawRequested(_) => {
+                println!("\nredrawing!\n");
+            }
+            _ => (),
         }
-        Event::RedrawRequested(_) => {
-            println!("{:?}", event);
-        }
-        _ => (),
     });
 }

examples/request_redraw_threaded.rs

@@ -0,0 +1,39 @@
+use std::{thread, time};
+
+use winit::{
+    event::{Event, WindowEvent},
+    event_loop::{ControlFlow, EventLoop},
+    window::WindowBuilder,
+};
+
+fn main() {
+    simple_logger::init().unwrap();
+    let event_loop = EventLoop::new();
+
+    let window = WindowBuilder::new()
+        .with_title("A fantastic window!")
+        .build(&event_loop)
+        .unwrap();
+
+    thread::spawn(move || loop {
+        thread::sleep(time::Duration::from_secs(1));
+        window.request_redraw();
+    });
+
+    event_loop.run(move |event, _, control_flow| {
+        println!("{:?}", event);
+
+        *control_flow = ControlFlow::Wait;
+
+        match event {
+            Event::WindowEvent { event, .. } => match event {
+                WindowEvent::CloseRequested => *control_flow = ControlFlow::Exit,
+                _ => (),
+            },
+            Event::RedrawRequested(_) => {
+                println!("\nredrawing!\n");
+            }
+            _ => (),
+        }
+    });
+}

examples/resizable.rs

@@ -1,23 +1,26 @@
 use winit::{
+    dpi::LogicalSize,
     event::{ElementState, Event, KeyboardInput, VirtualKeyCode, WindowEvent},
     event_loop::{ControlFlow, EventLoop},
     window::WindowBuilder,
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let mut resizable = false;
 
     let window = WindowBuilder::new()
         .with_title("Hit space to toggle resizability.")
-        .with_inner_size((400, 200).into())
+        .with_inner_size(LogicalSize::new(400.0, 200.0))
         .with_resizable(resizable)
         .build(&event_loop)
         .unwrap();
 
     event_loop.run(move |event, _, control_flow| {
         *control_flow = ControlFlow::Wait;
+
         match event {
             Event::WindowEvent { event, .. } => match event {
                 WindowEvent::CloseRequested => *control_flow = ControlFlow::Exit,

examples/timer.rs

@@ -7,6 +7,7 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let _window = WindowBuilder::new()

examples/transparent.rs

@@ -5,6 +5,7 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let window = WindowBuilder::new()
@@ -16,6 +17,7 @@ fn main() {
     window.set_title("A fantastic window!");
 
     event_loop.run(move |event, _, control_flow| {
+        *control_flow = ControlFlow::Wait;
         println!("{:?}", event);
 
         match event {
@@ -23,7 +25,7 @@ fn main() {
                 event: WindowEvent::CloseRequested,
                 ..
             } => *control_flow = ControlFlow::Exit,
-            _ => *control_flow = ControlFlow::Wait,
+            _ => (),
         }
     });
 }

examples/video_modes.rs

@@ -1,6 +1,7 @@
 use winit::event_loop::EventLoop;
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
     let monitor = event_loop.primary_monitor();
 

examples/web.rs

@@ -40,6 +40,8 @@ pub fn main() {
     }
 
     event_loop.run(move |event, _, control_flow| {
+        *control_flow = ControlFlow::Wait;
+
         #[cfg(feature = "web-sys")]
         log::debug!("{:?}", event);
 
@@ -54,7 +56,7 @@ pub fn main() {
             Event::MainEventsCleared => {
                 window.request_redraw();
             }
-            _ => *control_flow = ControlFlow::Wait,
+            _ => (),
         }
     });
 }

examples/window.rs

@@ -5,14 +5,17 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let window = WindowBuilder::new()
         .with_title("A fantastic window!")
+        .with_inner_size(winit::dpi::LogicalSize::new(128.0, 128.0))
         .build(&event_loop)
         .unwrap();
 
     event_loop.run(move |event, _, control_flow| {
+        *control_flow = ControlFlow::Wait;
         println!("{:?}", event);
 
         match event {
@@ -23,7 +26,7 @@ fn main() {
             Event::MainEventsCleared => {
                 window.request_redraw();
             }
-            _ => *control_flow = ControlFlow::Poll,
+            _ => (),
         }
     });
 }

examples/window_debug.rs

@@ -8,24 +8,23 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
     let event_loop = EventLoop::new();
 
     let window = WindowBuilder::new()
         .with_title("A fantastic window!")
-        .with_inner_size(LogicalSize::from((100, 100)))
+        .with_inner_size(LogicalSize::new(100.0, 100.0))
         .build(&event_loop)
         .unwrap();
 
     eprintln!("debugging keys:");
     eprintln!("  (E) Enter exclusive fullscreen");
     eprintln!("  (F) Toggle borderless fullscreen");
-    #[cfg(waiting_for_set_minimized)]
     eprintln!("  (M) Toggle minimized");
     eprintln!("  (Q) Quit event loop");
     eprintln!("  (V) Toggle visibility");
     eprintln!("  (X) Toggle maximized");
 
-    #[cfg(waiting_for_set_minimized)]
     let mut minimized = false;
     let mut maximized = false;
     let mut visible = true;
@@ -43,7 +42,6 @@ fn main() {
                     }),
                 ..
             } => match key {
-                #[cfg(waiting_for_set_minimized)]
                 VirtualKeyCode::M => {
                     if minimized {
                         minimized = !minimized;
@@ -68,16 +66,15 @@ fn main() {
                     ..
                 } => match key {
                     VirtualKeyCode::E => {
-                        fn area(size: PhysicalSize) -> f64 {
+                        fn area(size: PhysicalSize<u32>) -> u32 {
                             size.width * size.height
                         }
 
                         let monitor = window.current_monitor();
-                        if let Some(mode) = monitor.video_modes().max_by(|a, b| {
-                            area(a.size())
-                                .partial_cmp(&area(b.size()))
-                                .expect("NaN in video mode size")
-                        }) {
+                        if let Some(mode) = monitor
+                            .video_modes()
+                            .max_by(|a, b| area(a.size()).cmp(&area(b.size())))
+                        {
                             window.set_fullscreen(Some(Fullscreen::Exclusive(mode)));
                         } else {
                             eprintln!("no video modes available");
@@ -91,7 +88,6 @@ fn main() {
                             window.set_fullscreen(Some(Fullscreen::Borderless(monitor)));
                         }
                     }
-                    #[cfg(waiting_for_set_minimized)]
                     VirtualKeyCode::M => {
                         minimized = !minimized;
                         window.set_minimized(minimized);

examples/window_icon.rs

@@ -7,6 +7,8 @@ use winit::{
 };
 
 fn main() {
+    simple_logger::init().unwrap();
+
     // You'll have to choose an icon size at your own discretion. On X11, the desired size varies
     // by WM, and on Windows, you still have to account for screen scaling. Here we use 32px,
     // since it seems to work well enough in most cases. Be careful about going too high, or
@@ -27,6 +29,7 @@ fn main() {
 
     event_loop.run(move |event, _, control_flow| {
         *control_flow = ControlFlow::Wait;
+
         if let Event::WindowEvent { event, .. } = event {
             use winit::event::WindowEvent::*;
             match event {
@@ -42,13 +45,11 @@ fn main() {
 
 fn load_icon(path: &Path) -> Icon {
     let (icon_rgba, icon_width, icon_height) = {
-        let image = image::open(path).expect("Failed to open icon path");
-        use image::{GenericImageView, Pixel};
+        let image = image::open(path)
+            .expect("Failed to open icon path")
+            .into_rgba();
         let (width, height) = image.dimensions();
-        let mut rgba = Vec::with_capacity((width * height) as usize * 4);
-        for (_, _, pixel) in image.pixels() {
-            rgba.extend_from_slice(&pixel.to_rgba().data);
-        }
+        let rgba = image.into_raw();
         (rgba, width, height)
     };
     Icon::from_rgba(icon_rgba, icon_width, icon_height).expect("Failed to open icon")

examples/window_run_return.rs

@@ -18,6 +18,7 @@ fn main() {
     };
     let mut event_loop = EventLoop::new();
 
+    simple_logger::init().unwrap();
     let _window = WindowBuilder::new()
         .with_title("A fantastic window!")
         .build(&event_loop)
@@ -27,6 +28,8 @@ fn main() {
 
     while !quit {
         event_loop.run_return(|event, _, control_flow| {
+            *control_flow = ControlFlow::Wait;
+
             if let Event::WindowEvent { event, .. } = &event {
                 // Print only Window events to reduce noise
                 println!("{:?}", event);
@@ -38,16 +41,16 @@ fn main() {
                     ..
                 } => {
                     quit = true;
-                    *control_flow = ControlFlow::Exit;
                 }
                 Event::MainEventsCleared => {
                     *control_flow = ControlFlow::Exit;
                 }
-                _ => *control_flow = ControlFlow::Wait,
+                _ => (),
             }
         });
 
         // Sleep for 1/60 second to simulate rendering
+        println!("rendering");
         sleep(Duration::from_millis(16));
     }
 }

src/dpi.rs

@@ -1,331 +1,501 @@
-//! DPI is important, so read the docs for this module if you don't want to be confused.
+//! UI scaling is important, so read the docs for this module if you don't want to be confused.
 //!
-//! Originally, `winit` dealt entirely in physical pixels (excluding unintentional inconsistencies), but now all
-//! window-related functions both produce and consume logical pixels. Monitor-related functions still use physical
-//! pixels, as do any context-related functions in `glutin`.
+//! ## Why should I care about UI scaling?
 //!
-//! If you've never heard of these terms before, then you're not alone, and this documentation will explain the
-//! concepts.
+//! Modern computer screens don't have a consistent relationship between resolution and size.
+//! 1920x1080 is a common resolution for both desktop and mobile screens, despite mobile screens
+//! normally being less than a quarter the size of their desktop counterparts. What's more, neither
+//! desktop nor mobile screens are consistent resolutions within their own size classes - common
+//! mobile screens range from below 720p to above 1440p, and desktop screens range from 720p to 5K
+//! and beyond.
 //!
-//! Modern screens have a defined physical resolution, most commonly 1920x1080. Indepedent of that is the amount of
-//! space the screen occupies, which is to say, the height and width in millimeters. The relationship between these two
-//! measurements is the *pixel density*. Mobile screens require a high pixel density, as they're held close to the
-//! eyes. Larger displays also require a higher pixel density, hence the growing presence of 1440p and 4K displays.
+//! Given that, it's a mistake to assume that 2D content will only be displayed on screens with
+//! a consistent pixel density. If you were to render a 96-pixel-square image on a 1080p screen,
+//! then render the same image on a similarly-sized 4K screen, the 4K rendition would only take up
+//! about a quarter of the physical space as it did on the 1080p screen. That issue is especially
+//! problematic with text rendering, where quarter-sized text becomes a significant legibility
+//! problem.
 //!
-//! So, this presents a problem. Let's say we want to render a square 100px button. It will occupy 100x100 of the
-//! screen's pixels, which in many cases, seems perfectly fine. However, because this size doesn't account for the
-//! screen's dimensions or pixel density, the button's size can vary quite a bit. On a 4K display, it would be unusably
-//! small.
+//! Failure to account for the scale factor can create a significantly degraded user experience.
+//! Most notably, it can make users feel like they have bad eyesight, which will potentially cause
+//! them to think about growing elderly, resulting in them having an existential crisis. Once users
+//! enter that state, they will no longer be focused on your application.
 //!
-//! That's a description of what happens when the button is 100x100 *physical* pixels. Instead, let's try using 100x100
-//! *logical* pixels. To map logical pixels to physical pixels, we simply multiply by the DPI (dots per inch) factor.
-//! On a "typical" desktop display, the DPI factor will be 1.0, so 100x100 logical pixels equates to 100x100 physical
-//! pixels. However, a 1440p display may have a DPI factor of 1.25, so the button is rendered as 125x125 physical pixels.
-//! Ideally, the button now has approximately the same perceived size across varying displays.
+//! ## How should I handle it?
 //!
-//! Failure to account for the DPI factor can create a badly degraded user experience. Most notably, it can make users
-//! feel like they have bad eyesight, which will potentially cause them to think about growing elderly, resulting in
-//! them entering an existential panic. Once users enter that state, they will no longer be focused on your application.
+//! The solution to this problem is to account for the device's *scale factor*. The scale factor is
+//! the factor UI elements should be scaled by to be consistent with the rest of the user's system -
+//! for example, a button that's normally 50 pixels across would be 100 pixels across on a device
+//! with a scale factor of `2.0`, or 75 pixels across with a scale factor of `1.5`.
 //!
-//! There are two ways to get the DPI factor:
-//! - You can track the [`HiDpiFactorChanged`](crate::event::WindowEvent::HiDpiFactorChanged) event of your
-//!   windows. This event is sent any time the DPI factor changes, either because the window moved to another monitor,
-//!   or because the user changed the configuration of their screen.
-//! - You can also retrieve the DPI factor of a monitor by calling
-//!   [`MonitorHandle::hidpi_factor`](crate::monitor::MonitorHandle::hidpi_factor), or the
-//!   current DPI factor applied to a window by calling
-//!   [`Window::hidpi_factor`](crate::window::Window::hidpi_factor), which is roughly equivalent
-//!   to `window.current_monitor().hidpi_factor()`.
+//! Many UI systems, such as CSS, expose DPI-dependent units like [points] or [picas]. That's
+//! usually a mistake, since there's no consistent mapping between the scale factor and the screen's
+//! actual DPI. Unless you're printing to a physical medium, you should work in scaled pixels rather
+//! than any DPI-dependent units.
 //!
-//! Depending on the platform, the window's actual DPI factor may only be known after
-//! the event loop has started and your window has been drawn once. To properly handle these cases,
-//! the most robust way is to monitor the [`HiDpiFactorChanged`](crate::event::WindowEvent::HiDpiFactorChanged)
-//! event and dynamically adapt your drawing logic to follow the DPI factor.
+//! ### Position and Size types
 //!
-//! Here's an overview of what sort of DPI factors you can expect, and where they come from:
-//! - **Windows:** On Windows 8 and 10, per-monitor scaling is readily configured by users from the display settings.
-//! While users are free to select any option they want, they're only given a selection of "nice" DPI factors, i.e.
-//! 1.0, 1.25, 1.5... on Windows 7, the DPI factor is global and changing it requires logging out.
-//! - **macOS:** The buzzword is "retina displays", which have a DPI factor of 2.0. Otherwise, the DPI factor is 1.0.
-//! Intermediate DPI factors are never used, thus 1440p displays/etc. aren't properly supported. It's possible for any
-//! display to use that 2.0 DPI factor, given the use of the command line.
-//! - **X11:** On X11, we calculate the DPI factor based on the millimeter dimensions provided by XRandR. This can
-//! result in a wide range of possible values, including some interesting ones like 1.0833333333333333. This can be
-//! overridden using the `WINIT_HIDPI_FACTOR` environment variable, though that's not recommended.
-//! - **Wayland:** On Wayland, DPI factors are set per-screen by the server, and are always integers (most often 1 or 2).
-//! - **iOS:** DPI factors are both constant and device-specific on iOS.
-//! - **Android:** This feature isn't yet implemented on Android, so the DPI factor will always be returned as 1.0.
-//! - **Web:** DPI factors are handled by the browser and will always be 1.0 for your application.
+//! Winit's `Physical(Position|Size)` types correspond with the actual pixels on the device, and the
+//! `Logical(Position|Size)` types correspond to the physical pixels divided by the scale factor.
+//! All of Winit's functions return physical types, but can take either logical or physical
+//! coordinates as input, allowing you to use the most convenient coordinate system for your
+//! particular application.
 //!
-//! The window's logical size is conserved across DPI changes, resulting in the physical size changing instead. This
-//! may be surprising on X11, but is quite standard elsewhere. Physical size changes always produce a
-//! [`Resized`](crate::event::WindowEvent::Resized) event, even on platforms where no resize actually occurs,
-//! such as macOS and Wayland. As a result, it's not necessary to separately handle
-//! [`HiDpiFactorChanged`](crate::event::WindowEvent::HiDpiFactorChanged) if you're only listening for size.
+//! Winit's position and size types types are generic over their exact pixel type, `P`, to allow the
+//! API to have integer precision where appropriate (e.g. most window manipulation functions) and
+//! floating precision when necessary (e.g. logical sizes for fractional scale factors and touch
+//! input). If `P` is a floating-point type, please do not cast the values with `as {int}`. Doing so
+//! will truncate the fractional part of the float, rather than properly round to the nearest
+//! integer. Use the provided `cast` function or `From`/`Into` conversions, which handle the
+//! rounding properly. Note that precision loss will still occur when rounding from a float to an
+//! int, although rounding lessens the problem.
 //!
-//! Your GPU has no awareness of the concept of logical pixels, and unless you like wasting pixel density, your
-//! framebuffer's size should be in physical pixels.
+//! ### Events
 //!
-//! `winit` will send [`Resized`](crate::event::WindowEvent::Resized) events whenever a window's logical size
-//! changes, and [`HiDpiFactorChanged`](crate::event::WindowEvent::HiDpiFactorChanged) events
-//! whenever the DPI factor changes. Receiving either of these events means that the physical size of your window has
-//! changed, and you should recompute it using the latest values you received for each. If the logical size and the
-//! DPI factor change simultaneously, `winit` will send both events together; thus, it's recommended to buffer
-//! these events and process them at the end of the queue.
+//! Winit will dispatch a [`ScaleFactorChanged`](crate::event::WindowEvent::ScaleFactorChanged)
+//! event whenever a window's scale factor has changed. This can happen if the user drags their
+//! window from a standard-resolution monitor to a high-DPI monitor, or if the user changes their
+//! DPI settings. This gives you a chance to rescale your application's UI elements and adjust how
+//! the platform changes the window's size to reflect the new scale factor. If a window hasn't
+//! received a [`ScaleFactorChanged`](crate::event::WindowEvent::ScaleFactorChanged) event,
+//! then its scale factor is `1.0`.
 //!
-//! If you never received any [`HiDpiFactorChanged`](crate::event::WindowEvent::HiDpiFactorChanged) events,
-//! then your window's DPI factor is 1.
+//! ## How is the scale factor calculated?
+//!
+//! Scale factor is calculated differently on different platforms:
+//!
+//! - **Windows:** On Windows 8 and 10, per-monitor scaling is readily configured by users from the
+//!   display settings. While users are free to select any option they want, they're only given a
+//!   selection of "nice" scale factors, i.e. 1.0, 1.25, 1.5... on Windows 7, the scale factor is
+//!   global and changing it requires logging out. See [this article][windows_1] for technical
+//!   details.
+//! - **macOS:** "retina displays" have a scale factor of 2.0. Otherwise, the scale factor is 1.0.
+//!   Intermediate scale factors are never used. It's possible for any display to use that 2.0 scale
+//!   factor, given the use of the command line.
+//! - **X11:** Many man-hours have been spent trying to figure out how to handle DPI in X11. Winit
+//!   currently uses a three-pronged approach:
+//!   + Use the value in the `WINIT_X11_SCALE_FACTOR` environment variable, if present.
+//!   + If not present, use the value set in `Xft.dpi` in Xresources.
+//!   + Otherwise, calcuate the scale factor based on the millimeter monitor dimensions provided by XRandR.
+//!
+//!   If `WINIT_X11_SCALE_FACTOR` is set to `randr`, it'll ignore the `Xft.dpi` field and use the
+//!   XRandR scaling method. Generally speaking, you should try to configure the standard system
+//!   variables to do what you want before resorting to `WINIT_X11_SCALE_FACTOR`.
+//! - **Wayland:** On Wayland, scale factors are set per-screen by the server, and are always
+//!   integers (most often 1 or 2).
+//! - **iOS:** Scale factors are set by Apple to the value that best suits the device, and range
+//!   from `1.0` to `3.0`. See [this article][apple_1] and [this article][apple_2] for more
+//!   information.
+//! - **Android:** Scale factors are set by the manufacturer to the value that best suits the
+//!   device, and range from `1.0` to `4.0`. See [this article][android_1] for more information.
+//! - **Web:** The scale factor is the ratio between CSS pixels and the physical device pixels.
+//!
+//! [points]: https://en.wikipedia.org/wiki/Point_(typography)
+//! [picas]: https://en.wikipedia.org/wiki/Pica_(typography)
+//! [windows_1]: https://docs.microsoft.com/en-us/windows/win32/hidpi/high-dpi-desktop-application-development-on-windows
+//! [apple_1]: https://developer.apple.com/library/archive/documentation/DeviceInformation/Reference/iOSDeviceCompatibility/Displays/Displays.html
+//! [apple_2]: https://developer.apple.com/design/human-interface-guidelines/macos/icons-and-images/image-size-and-resolution/
+//! [android_1]: https://developer.android.com/training/multiscreen/screendensities
 
-/// Checks that the DPI factor is a normal positive `f64`.
+pub trait Pixel: Copy + Into<f64> {
+    fn from_f64(f: f64) -> Self;
+    fn cast<P: Pixel>(self) -> P {
+        P::from_f64(self.into())
+    }
+}
+
+impl Pixel for u8 {
+    fn from_f64(f: f64) -> Self {
+        f.round() as u8
+    }
+}
+impl Pixel for u16 {
+    fn from_f64(f: f64) -> Self {
+        f.round() as u16
+    }
+}
+impl Pixel for u32 {
+    fn from_f64(f: f64) -> Self {
+        f.round() as u32
+    }
+}
+impl Pixel for i8 {
+    fn from_f64(f: f64) -> Self {
+        f.round() as i8
+    }
+}
+impl Pixel for i16 {
+    fn from_f64(f: f64) -> Self {
+        f.round() as i16
+    }
+}
+impl Pixel for i32 {
+    fn from_f64(f: f64) -> Self {
+        f.round() as i32
+    }
+}
+impl Pixel for f32 {
+    fn from_f64(f: f64) -> Self {
+        f as f32
+    }
+}
+impl Pixel for f64 {
+    fn from_f64(f: f64) -> Self {
+        f
+    }
+}
+
+/// Checks that the scale factor is a normal positive `f64`.
 ///
-/// All functions that take a DPI factor assert that this will return `true`. If you're sourcing DPI factors from
+/// All functions that take a scale factor assert that this will return `true`. If you're sourcing scale factors from
 /// anywhere other than winit, it's recommended to validate them using this function before passing them to winit;
 /// otherwise, you risk panics.
 #[inline]
-pub fn validate_hidpi_factor(dpi_factor: f64) -> bool {
-    dpi_factor.is_sign_positive() && dpi_factor.is_normal()
+pub fn validate_scale_factor(scale_factor: f64) -> bool {
+    scale_factor.is_sign_positive() && scale_factor.is_normal()
 }
 
 /// A position represented in logical pixels.
 ///
-/// The position is stored as floats, so please be careful. Casting floats to integers truncates the fractional part,
-/// which can cause noticable issues. To help with that, an `Into<(i32, i32)>` implementation is provided which
-/// does the rounding for you.
+/// The position is stored as floats, so please be careful. Casting floats to integers truncates the
+/// fractional part, which can cause noticable issues. To help with that, an `Into<(i32, i32)>`
+/// implementation is provided which does the rounding for you.
 #[derive(Debug, Copy, Clone, PartialEq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-pub struct LogicalPosition {
-    pub x: f64,
-    pub y: f64,
+pub struct LogicalPosition<P> {
+    pub x: P,
+    pub y: P,
 }
 
-impl LogicalPosition {
+impl<P> LogicalPosition<P> {
     #[inline]
-    pub fn new(x: f64, y: f64) -> Self {
+    pub const fn new(x: P, y: P) -> Self {
         LogicalPosition { x, y }
     }
+}
 
+impl<P: Pixel> LogicalPosition<P> {
     #[inline]
-    pub fn from_physical<T: Into<PhysicalPosition>>(physical: T, dpi_factor: f64) -> Self {
-        physical.into().to_logical(dpi_factor)
+    pub fn from_physical<T: Into<PhysicalPosition<X>>, X: Pixel>(
+        physical: T,
+        scale_factor: f64,
+    ) -> Self {
+        physical.into().to_logical(scale_factor)
     }
 
     #[inline]
-    pub fn to_physical(&self, dpi_factor: f64) -> PhysicalPosition {
-        assert!(validate_hidpi_factor(dpi_factor));
-        let x = self.x * dpi_factor;
-        let y = self.y * dpi_factor;
-        PhysicalPosition::new(x, y)
+    pub fn to_physical<X: Pixel>(&self, scale_factor: f64) -> PhysicalPosition<X> {
+        assert!(validate_scale_factor(scale_factor));
+        let x = self.x.into() * scale_factor;
+        let y = self.y.into() * scale_factor;
+        PhysicalPosition::new(x, y).cast()
+    }
+
+    #[inline]
+    pub fn cast<X: Pixel>(&self) -> LogicalPosition<X> {
+        LogicalPosition {
+            x: self.x.cast(),
+            y: self.y.cast(),
+        }
     }
 }
 
-impl From<(f64, f64)> for LogicalPosition {
-    #[inline]
-    fn from((x, y): (f64, f64)) -> Self {
-        Self::new(x, y)
+impl<P: Pixel, X: Pixel> From<(X, X)> for LogicalPosition<P> {
+    fn from((x, y): (X, X)) -> LogicalPosition<P> {
+        LogicalPosition::new(x.cast(), y.cast())
     }
 }
 
-impl From<(i32, i32)> for LogicalPosition {
-    #[inline]
-    fn from((x, y): (i32, i32)) -> Self {
-        Self::new(x as f64, y as f64)
+impl<P: Pixel, X: Pixel> Into<(X, X)> for LogicalPosition<P> {
+    fn into(self: Self) -> (X, X) {
+        (self.x.cast(), self.y.cast())
     }
 }
 
-impl Into<(f64, f64)> for LogicalPosition {
-    #[inline]
-    fn into(self) -> (f64, f64) {
-        (self.x, self.y)
+impl<P: Pixel, X: Pixel> From<[X; 2]> for LogicalPosition<P> {
+    fn from([x, y]: [X; 2]) -> LogicalPosition<P> {
+        LogicalPosition::new(x.cast(), y.cast())
     }
 }
 
-impl Into<(i32, i32)> for LogicalPosition {
-    /// Note that this rounds instead of truncating.
-    #[inline]
-    fn into(self) -> (i32, i32) {
-        (self.x.round() as _, self.y.round() as _)
+impl<P: Pixel, X: Pixel> Into<[X; 2]> for LogicalPosition<P> {
+    fn into(self: Self) -> [X; 2] {
+        [self.x.cast(), self.y.cast()]
     }
 }
 
 /// A position represented in physical pixels.
-///
-/// The position is stored as floats, so please be careful. Casting floats to integers truncates the fractional part,
-/// which can cause noticable issues. To help with that, an `Into<(i32, i32)>` implementation is provided which
-/// does the rounding for you.
 #[derive(Debug, Copy, Clone, PartialEq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-pub struct PhysicalPosition {
-    pub x: f64,
-    pub y: f64,
+pub struct PhysicalPosition<P> {
+    pub x: P,
+    pub y: P,
 }
 
-impl PhysicalPosition {
+impl<P> PhysicalPosition<P> {
     #[inline]
-    pub fn new(x: f64, y: f64) -> Self {
+    pub const fn new(x: P, y: P) -> Self {
         PhysicalPosition { x, y }
     }
+}
 
+impl<P: Pixel> PhysicalPosition<P> {
     #[inline]
-    pub fn from_logical<T: Into<LogicalPosition>>(logical: T, dpi_factor: f64) -> Self {
-        logical.into().to_physical(dpi_factor)
+    pub fn from_logical<T: Into<LogicalPosition<X>>, X: Pixel>(
+        logical: T,
+        scale_factor: f64,
+    ) -> Self {
+        logical.into().to_physical(scale_factor)
     }
 
     #[inline]
-    pub fn to_logical(&self, dpi_factor: f64) -> LogicalPosition {
-        assert!(validate_hidpi_factor(dpi_factor));
-        let x = self.x / dpi_factor;
-        let y = self.y / dpi_factor;
-        LogicalPosition::new(x, y)
+    pub fn to_logical<X: Pixel>(&self, scale_factor: f64) -> LogicalPosition<X> {
+        assert!(validate_scale_factor(scale_factor));
+        let x = self.x.into() / scale_factor;
+        let y = self.y.into() / scale_factor;
+        LogicalPosition::new(x, y).cast()
+    }
+
+    #[inline]
+    pub fn cast<X: Pixel>(&self) -> PhysicalPosition<X> {
+        PhysicalPosition {
+            x: self.x.cast(),
+            y: self.y.cast(),
+        }
     }
 }
 
-impl From<(f64, f64)> for PhysicalPosition {
-    #[inline]
-    fn from((x, y): (f64, f64)) -> Self {
-        Self::new(x, y)
+impl<P: Pixel, X: Pixel> From<(X, X)> for PhysicalPosition<P> {
+    fn from((x, y): (X, X)) -> PhysicalPosition<P> {
+        PhysicalPosition::new(x.cast(), y.cast())
     }
 }
 
-impl From<(i32, i32)> for PhysicalPosition {
-    #[inline]
-    fn from((x, y): (i32, i32)) -> Self {
-        Self::new(x as f64, y as f64)
+impl<P: Pixel, X: Pixel> Into<(X, X)> for PhysicalPosition<P> {
+    fn into(self: Self) -> (X, X) {
+        (self.x.cast(), self.y.cast())
     }
 }
 
-impl Into<(f64, f64)> for PhysicalPosition {
-    #[inline]
-    fn into(self) -> (f64, f64) {
-        (self.x, self.y)
+impl<P: Pixel, X: Pixel> From<[X; 2]> for PhysicalPosition<P> {
+    fn from([x, y]: [X; 2]) -> PhysicalPosition<P> {
+        PhysicalPosition::new(x.cast(), y.cast())
     }
 }
 
-impl Into<(i32, i32)> for PhysicalPosition {
-    /// Note that this rounds instead of truncating.
-    #[inline]
-    fn into(self) -> (i32, i32) {
-        (self.x.round() as _, self.y.round() as _)
+impl<P: Pixel, X: Pixel> Into<[X; 2]> for PhysicalPosition<P> {
+    fn into(self: Self) -> [X; 2] {
+        [self.x.cast(), self.y.cast()]
     }
 }
 
 /// A size represented in logical pixels.
-///
-/// The size is stored as floats, so please be careful. Casting floats to integers truncates the fractional part,
-/// which can cause noticable issues. To help with that, an `Into<(u32, u32)>` implementation is provided which
-/// does the rounding for you.
 #[derive(Debug, Copy, Clone, PartialEq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-pub struct LogicalSize {
-    pub width: f64,
-    pub height: f64,
+pub struct LogicalSize<P> {
+    pub width: P,
+    pub height: P,
 }
 
-impl LogicalSize {
+impl<P> LogicalSize<P> {
     #[inline]
-    pub fn new(width: f64, height: f64) -> Self {
+    pub const fn new(width: P, height: P) -> Self {
         LogicalSize { width, height }
     }
+}
 
+impl<P: Pixel> LogicalSize<P> {
     #[inline]
-    pub fn from_physical<T: Into<PhysicalSize>>(physical: T, dpi_factor: f64) -> Self {
-        physical.into().to_logical(dpi_factor)
+    pub fn from_physical<T: Into<PhysicalSize<X>>, X: Pixel>(
+        physical: T,
+        scale_factor: f64,
+    ) -> Self {
+        physical.into().to_logical(scale_factor)
     }
 
     #[inline]
-    pub fn to_physical(&self, dpi_factor: f64) -> PhysicalSize {
-        assert!(validate_hidpi_factor(dpi_factor));
-        let width = self.width * dpi_factor;
-        let height = self.height * dpi_factor;
-        PhysicalSize::new(width, height)
+    pub fn to_physical<X: Pixel>(&self, scale_factor: f64) -> PhysicalSize<X> {
+        assert!(validate_scale_factor(scale_factor));
+        let width = self.width.into() * scale_factor;
+        let height = self.height.into() * scale_factor;
+        PhysicalSize::new(width, height).cast()
+    }
+
+    #[inline]
+    pub fn cast<X: Pixel>(&self) -> LogicalSize<X> {
+        LogicalSize {
+            width: self.width.cast(),
+            height: self.height.cast(),
+        }
     }
 }
 
-impl From<(f64, f64)> for LogicalSize {
-    #[inline]
-    fn from((width, height): (f64, f64)) -> Self {
-        Self::new(width, height)
+impl<P: Pixel, X: Pixel> From<(X, X)> for LogicalSize<P> {
+    fn from((x, y): (X, X)) -> LogicalSize<P> {
+        LogicalSize::new(x.cast(), y.cast())
     }
 }
 
-impl From<(u32, u32)> for LogicalSize {
-    #[inline]
-    fn from((width, height): (u32, u32)) -> Self {
-        Self::new(width as f64, height as f64)
+impl<P: Pixel, X: Pixel> Into<(X, X)> for LogicalSize<P> {
+    fn into(self: LogicalSize<P>) -> (X, X) {
+        (self.width.cast(), self.height.cast())
     }
 }
 
-impl Into<(f64, f64)> for LogicalSize {
-    #[inline]
-    fn into(self) -> (f64, f64) {
-        (self.width, self.height)
+impl<P: Pixel, X: Pixel> From<[X; 2]> for LogicalSize<P> {
+    fn from([x, y]: [X; 2]) -> LogicalSize<P> {
+        LogicalSize::new(x.cast(), y.cast())
     }
 }
 
-impl Into<(u32, u32)> for LogicalSize {
-    /// Note that this rounds instead of truncating.
-    #[inline]
-    fn into(self) -> (u32, u32) {
-        (self.width.round() as _, self.height.round() as _)
+impl<P: Pixel, X: Pixel> Into<[X; 2]> for LogicalSize<P> {
+    fn into(self: Self) -> [X; 2] {
+        [self.width.cast(), self.height.cast()]
     }
 }
 
 /// A size represented in physical pixels.
-///
-/// The size is stored as floats, so please be careful. Casting floats to integers truncates the fractional part,
-/// which can cause noticable issues. To help with that, an `Into<(u32, u32)>` implementation is provided which
-/// does the rounding for you.
-#[derive(Debug, Copy, Clone, PartialEq)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-pub struct PhysicalSize {
-    pub width: f64,
-    pub height: f64,
+pub struct PhysicalSize<P> {
+    pub width: P,
+    pub height: P,
 }
 
-impl PhysicalSize {
+impl<P> PhysicalSize<P> {
     #[inline]
-    pub fn new(width: f64, height: f64) -> Self {
+    pub const fn new(width: P, height: P) -> Self {
         PhysicalSize { width, height }
     }
+}
 
+impl<P: Pixel> PhysicalSize<P> {
     #[inline]
-    pub fn from_logical<T: Into<LogicalSize>>(logical: T, dpi_factor: f64) -> Self {
-        logical.into().to_physical(dpi_factor)
+    pub fn from_logical<T: Into<LogicalSize<X>>, X: Pixel>(logical: T, scale_factor: f64) -> Self {
+        logical.into().to_physical(scale_factor)
     }
 
     #[inline]
-    pub fn to_logical(&self, dpi_factor: f64) -> LogicalSize {
-        assert!(validate_hidpi_factor(dpi_factor));
-        let width = self.width / dpi_factor;
-        let height = self.height / dpi_factor;
-        LogicalSize::new(width, height)
+    pub fn to_logical<X: Pixel>(&self, scale_factor: f64) -> LogicalSize<X> {
+        assert!(validate_scale_factor(scale_factor));
+        let width = self.width.into() / scale_factor;
+        let height = self.height.into() / scale_factor;
+        LogicalSize::new(width, height).cast()
+    }
+
+    #[inline]
+    pub fn cast<X: Pixel>(&self) -> PhysicalSize<X> {
+        PhysicalSize {
+            width: self.width.cast(),
+            height: self.height.cast(),
+        }
     }
 }
 
-impl From<(f64, f64)> for PhysicalSize {
-    #[inline]
-    fn from((width, height): (f64, f64)) -> Self {
-        Self::new(width, height)
+impl<P: Pixel, X: Pixel> From<(X, X)> for PhysicalSize<P> {
+    fn from((x, y): (X, X)) -> PhysicalSize<P> {
+        PhysicalSize::new(x.cast(), y.cast())
     }
 }
 
-impl From<(u32, u32)> for PhysicalSize {
-    #[inline]
-    fn from((width, height): (u32, u32)) -> Self {
-        Self::new(width as f64, height as f64)
+impl<P: Pixel, X: Pixel> Into<(X, X)> for PhysicalSize<P> {
+    fn into(self: Self) -> (X, X) {
+        (self.width.cast(), self.height.cast())
     }
 }
 
-impl Into<(f64, f64)> for PhysicalSize {
-    #[inline]
-    fn into(self) -> (f64, f64) {
-        (self.width, self.height)
+impl<P: Pixel, X: Pixel> From<[X; 2]> for PhysicalSize<P> {
+    fn from([x, y]: [X; 2]) -> PhysicalSize<P> {
+        PhysicalSize::new(x.cast(), y.cast())
     }
 }
 
-impl Into<(u32, u32)> for PhysicalSize {
-    /// Note that this rounds instead of truncating.
-    #[inline]
-    fn into(self) -> (u32, u32) {
-        (self.width.round() as _, self.height.round() as _)
+impl<P: Pixel, X: Pixel> Into<[X; 2]> for PhysicalSize<P> {
+    fn into(self: Self) -> [X; 2] {
+        [self.width.cast(), self.height.cast()]
+    }
+}
+
+/// A size that's either physical or logical.
+#[derive(Debug, Copy, Clone, PartialEq)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub enum Size {
+    Physical(PhysicalSize<u32>),
+    Logical(LogicalSize<f64>),
+}
+
+impl Size {
+    pub fn new<S: Into<Size>>(size: S) -> Size {
+        size.into()
+    }
+
+    pub fn to_logical<P: Pixel>(&self, scale_factor: f64) -> LogicalSize<P> {
+        match *self {
+            Size::Physical(size) => size.to_logical(scale_factor),
+            Size::Logical(size) => size.cast(),
+        }
+    }
+
+    pub fn to_physical<P: Pixel>(&self, scale_factor: f64) -> PhysicalSize<P> {
+        match *self {
+            Size::Physical(size) => size.cast(),
+            Size::Logical(size) => size.to_physical(scale_factor),
+        }
+    }
+}
+
+impl<P: Pixel> From<PhysicalSize<P>> for Size {
+    #[inline]
+    fn from(size: PhysicalSize<P>) -> Size {
+        Size::Physical(size.cast())
+    }
+}
+
+impl<P: Pixel> From<LogicalSize<P>> for Size {
+    #[inline]
+    fn from(size: LogicalSize<P>) -> Size {
+        Size::Logical(size.cast())
+    }
+}
+
+/// A position that's either physical or logical.
+#[derive(Debug, Copy, Clone, PartialEq)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub enum Position {
+    Physical(PhysicalPosition<i32>),
+    Logical(LogicalPosition<f64>),
+}
+
+impl Position {
+    pub fn new<S: Into<Position>>(position: S) -> Position {
+        position.into()
+    }
+
+    pub fn to_logical<P: Pixel>(&self, scale_factor: f64) -> LogicalPosition<P> {
+        match *self {
+            Position::Physical(position) => position.to_logical(scale_factor),
+            Position::Logical(position) => position.cast(),
+        }
+    }
+
+    pub fn to_physical<P: Pixel>(&self, scale_factor: f64) -> PhysicalPosition<P> {
+        match *self {
+            Position::Physical(position) => position.cast(),
+            Position::Logical(position) => position.to_physical(scale_factor),
+        }
+    }
+}
+
+impl<P: Pixel> From<PhysicalPosition<P>> for Position {
+    #[inline]
+    fn from(position: PhysicalPosition<P>) -> Position {
+        Position::Physical(position.cast())
+    }
+}
+
+impl<P: Pixel> From<LogicalPosition<P>> for Position {
+    #[inline]
+    fn from(position: LogicalPosition<P>) -> Position {
+        Position::Logical(position.cast())
     }
 }

src/event.rs

@@ -3,63 +3,119 @@
 //! These are sent to the closure given to [`EventLoop::run(...)`][event_loop_run], where they get
 //! processed and used to modify the program state. For more details, see the root-level documentation.
 //!
+//! Some of these events represent different "parts" of a traditional event-handling loop. You could
+//! approximate the basic ordering loop of [`EventLoop::run(...)`][event_loop_run] like this:
+//!
+//! ```rust,ignore
+//! let mut control_flow = ControlFlow::Poll;
+//! let mut start_cause = StartCause::Init;
+//!
+//! while control_flow != ControlFlow::Exit {
+//!     event_handler(NewEvents(start_cause), ..., &mut control_flow);
+//!
+//!     for e in (window events, user events, device events) {
+//!         event_handler(e, ..., &mut control_flow);
+//!     }
+//!     event_handler(MainEventsCleared, ..., &mut control_flow);
+//!
+//!     for w in (redraw windows) {
+//!         event_handler(RedrawRequested(w), ..., &mut control_flow);
+//!     }
+//!     event_handler(RedrawEventsCleared, ..., &mut control_flow);
+//!
+//!     start_cause = wait_if_necessary(control_flow);
+//! }
+//!
+//! event_handler(LoopDestroyed, ..., &mut control_flow);
+//! ```
+//!
+//! This leaves out timing details like `ControlFlow::WaitUntil` but hopefully
+//! describes what happens in what order.
+//!
 //! [event_loop_run]: crate::event_loop::EventLoop::run
 use instant::Instant;
 use std::path::PathBuf;
 
 use crate::{
-    dpi::{LogicalPosition, LogicalSize},
+    dpi::{LogicalPosition, PhysicalPosition, PhysicalSize},
     platform_impl,
     window::{Theme, WindowId},
 };
 
 /// Describes a generic event.
-#[derive(Clone, Debug, PartialEq)]
-pub enum Event<T> {
+///
+/// See the module-level docs for more information on the event loop manages each event.
+#[derive(Debug, PartialEq)]
+pub enum Event<'a, T: 'static> {
+    /// Emitted when new events arrive from the OS to be processed.
+    ///
+    /// This event type is useful as a place to put code that should be done before you start
+    /// processing events, such as updating frame timing information for benchmarking or checking
+    /// the [`StartCause`][crate::event::StartCause] to see if a timer set by
+    /// [`ControlFlow::WaitUntil`](crate::event_loop::ControlFlow::WaitUntil) has elapsed.
+    NewEvents(StartCause),
+
     /// Emitted when the OS sends an event to a winit window.
     WindowEvent {
         window_id: WindowId,
-        event: WindowEvent,
+        event: WindowEvent<'a>,
     },
+
     /// Emitted when the OS sends an event to a device.
     DeviceEvent {
         device_id: DeviceId,
         event: DeviceEvent,
     },
+
     /// Emitted when an event is sent from [`EventLoopProxy::send_event`](crate::event_loop::EventLoopProxy::send_event)
     UserEvent(T),
-    /// Emitted when new events arrive from the OS to be processed.
-    NewEvents(StartCause),
-    /// Emitted when all events (except for `RedrawRequested`) have been reported.
-    ///
-    /// This event is followed by zero or more instances of `RedrawRequested`
-    /// and, finally, `RedrawEventsCleared`.
-    MainEventsCleared,
-
-    /// The OS or application has requested that a window be redrawn.
-    ///
-    /// Emitted only after `MainEventsCleared`.
-    RedrawRequested(WindowId),
-
-    /// Emitted after any `RedrawRequested` events.
-    ///
-    /// If there are no `RedrawRequested` events, it is reported immediately after
-    /// `MainEventsCleared`.
-    RedrawEventsCleared,
-
-    /// Emitted when the event loop is being shut down. This is irreversable - if this event is
-    /// emitted, it is guaranteed to be the last event emitted.
-    LoopDestroyed,
 
     /// Emitted when the application has been suspended.
     Suspended,
 
     /// Emitted when the application has been resumed.
     Resumed,
+
+    /// Emitted when all of the event loop's input events have been processed and redraw processing
+    /// is about to begin.
+    ///
+    /// This event is useful as a place to put your code that should be run after all
+    /// state-changing events have been handled and you want to do stuff (updating state, performing
+    /// calculations, etc) that happens as the "main body" of your event loop. If your program draws
+    /// graphics, it's usually better to do it in response to
+    /// [`Event::RedrawRequested`](crate::event::Event::RedrawRequested), which gets emitted
+    /// immediately after this event.
+    MainEventsCleared,
+
+    /// Emitted after `MainEventsCleared` when a window should be redrawn.
+    ///
+    /// This gets triggered in two scenarios:
+    /// - The OS has performed an operation that's invalidated the window's contents (such as
+    ///   resizing the window).
+    /// - The application has explicitly requested a redraw via
+    ///   [`Window::request_redraw`](crate::window::Window::request_redraw).
+    ///
+    /// During each iteration of the event loop, Winit will aggregate duplicate redraw requests
+    /// into a single event, to help avoid duplicating rendering work.
+    RedrawRequested(WindowId),
+
+    /// Emitted after all `RedrawRequested` events have been processed and control flow is about to
+    /// be taken away from the program. If there are no `RedrawRequested` events, it is emitted
+    /// immediately after `MainEventsCleared`.
+    ///
+    /// This event is useful for doing any cleanup or bookkeeping work after all the rendering
+    /// tasks have been completed.
+    RedrawEventsCleared,
+
+    /// Emitted when the event loop is being shut down.
+    ///
+    /// This is irreversable - if this event is emitted, it is guaranteed to be the last event that
+    /// gets emitted. You generally want to treat this as an "do on quit" event.
+    LoopDestroyed,
 }
 
-impl<T> Event<T> {
-    pub fn map_nonuser_event<U>(self) -> Result<Event<U>, Event<T>> {
+impl<'a, T> Event<'a, T> {
+    pub fn map_nonuser_event<U>(self) -> Result<Event<'a, U>, Event<'a, T>> {
         use self::Event::*;
         match self {
             UserEvent(_) => Err(self),
@@ -74,6 +130,26 @@ impl<T> Event<T> {
             Resumed => Ok(Resumed),
         }
     }
+
+    /// If the event doesn't contain a reference, turn it into an event with a `'static` lifetime.
+    /// Otherwise, return `None`.
+    pub fn to_static(self) -> Option<Event<'static, T>> {
+        use self::Event::*;
+        match self {
+            WindowEvent { window_id, event } => event
+                .to_static()
+                .map(|event| WindowEvent { window_id, event }),
+            UserEvent(event) => Some(UserEvent(event)),
+            DeviceEvent { device_id, event } => Some(DeviceEvent { device_id, event }),
+            NewEvents(cause) => Some(NewEvents(cause)),
+            MainEventsCleared => Some(MainEventsCleared),
+            RedrawRequested(wid) => Some(RedrawRequested(wid)),
+            RedrawEventsCleared => Some(RedrawEventsCleared),
+            LoopDestroyed => Some(LoopDestroyed),
+            Suspended => Some(Suspended),
+            Resumed => Some(Resumed),
+        }
+    }
 }
 
 /// Describes the reason the event loop is resuming.
@@ -103,13 +179,13 @@ pub enum StartCause {
 }
 
 /// Describes an event from a `Window`.
-#[derive(Clone, Debug, PartialEq)]
-pub enum WindowEvent {
+#[derive(Debug, PartialEq)]
+pub enum WindowEvent<'a> {
     /// The size of the window has changed. Contains the client area's new dimensions.
-    Resized(LogicalSize),
+    Resized(PhysicalSize<u32>),
 
     /// The position of the window has changed. Contains the window's new position.
-    Moved(LogicalPosition),
+    Moved(PhysicalPosition<i32>),
 
     /// The window has been requested to close.
     CloseRequested,
@@ -159,6 +235,13 @@ pub enum WindowEvent {
         is_synthetic: bool,
     },
 
+    /// The keyboard modifiers have changed.
+    ///
+    /// Platform-specific behavior:
+    /// - **Web**: This API is currently unimplemented on the web. This isn't by design - it's an
+    ///   issue, and it should get fixed - but it's the current state of the API.
+    ModifiersChanged(ModifiersState),
+
     /// The cursor has moved on the window.
     CursorMoved {
         device_id: DeviceId,
@@ -166,8 +249,8 @@ pub enum WindowEvent {
         /// (x,y) coords in pixels relative to the top-left corner of the window. Because the range of this data is
         /// limited by the display area and it may have been transformed by the OS to implement effects such as cursor
         /// acceleration, it should not be used to implement non-cursor-like interactions such as 3D camera control.
-        position: LogicalPosition,
-        #[deprecated = "Deprecated in favor of DeviceEvent::ModifiersChanged"]
+        position: PhysicalPosition<f64>,
+        #[deprecated = "Deprecated in favor of WindowEvent::ModifiersChanged"]
         modifiers: ModifiersState,
     },
 
@@ -182,7 +265,7 @@ pub enum WindowEvent {
         device_id: DeviceId,
         delta: MouseScrollDelta,
         phase: TouchPhase,
-        #[deprecated = "Deprecated in favor of DeviceEvent::ModifiersChanged"]
+        #[deprecated = "Deprecated in favor of WindowEvent::ModifiersChanged"]
         modifiers: ModifiersState,
     },
 
@@ -191,7 +274,7 @@ pub enum WindowEvent {
         device_id: DeviceId,
         state: ElementState,
         button: MouseButton,
-        #[deprecated = "Deprecated in favor of DeviceEvent::ModifiersChanged"]
+        #[deprecated = "Deprecated in favor of WindowEvent::ModifiersChanged"]
         modifiers: ModifiersState,
     },
 
@@ -216,16 +299,23 @@ pub enum WindowEvent {
     /// Touch event has been received
     Touch(Touch),
 
-    /// The DPI factor of the window has changed.
+    /// The window's scale factor has changed.
     ///
     /// The following user actions can cause DPI changes:
     ///
     /// * Changing the display's resolution.
-    /// * Changing the display's DPI factor (e.g. in Control Panel on Windows).
-    /// * Moving the window to a display with a different DPI factor.
+    /// * Changing the display's scale factor (e.g. in Control Panel on Windows).
+    /// * Moving the window to a display with a different scale factor.
+    ///
+    /// After this event callback has been processed, the window will be resized to whatever value
+    /// is pointed to by the `new_inner_size` reference. By default, this will contain the size suggested
+    /// by the OS, but it can be changed to any value.
     ///
     /// For more information about DPI in general, see the [`dpi`](crate::dpi) module.
-    HiDpiFactorChanged(f64),
+    ScaleFactorChanged {
+        scale_factor: f64,
+        new_inner_size: &'a mut PhysicalSize<u32>,
+    },
 
     /// The system window theme has changed.
     ///
@@ -236,6 +326,90 @@ pub enum WindowEvent {
     ThemeChanged(Theme),
 }
 
+impl<'a> WindowEvent<'a> {
+    pub fn to_static(self) -> Option<WindowEvent<'static>> {
+        use self::WindowEvent::*;
+        match self {
+            Resized(size) => Some(Resized(size)),
+            Moved(position) => Some(Moved(position)),
+            CloseRequested => Some(CloseRequested),
+            Destroyed => Some(Destroyed),
+            DroppedFile(file) => Some(DroppedFile(file)),
+            HoveredFile(file) => Some(HoveredFile(file)),
+            HoveredFileCancelled => Some(HoveredFileCancelled),
+            ReceivedCharacter(c) => Some(ReceivedCharacter(c)),
+            Focused(focused) => Some(Focused(focused)),
+            KeyboardInput {
+                device_id,
+                input,
+                is_synthetic,
+            } => Some(KeyboardInput {
+                device_id,
+                input,
+                is_synthetic,
+            }),
+            ModifiersChanged(modifiers) => Some(ModifiersChanged(modifiers)),
+            #[allow(deprecated)]
+            CursorMoved {
+                device_id,
+                position,
+                modifiers,
+            } => Some(CursorMoved {
+                device_id,
+                position,
+                modifiers,
+            }),
+            CursorEntered { device_id } => Some(CursorEntered { device_id }),
+            CursorLeft { device_id } => Some(CursorLeft { device_id }),
+            #[allow(deprecated)]
+            MouseWheel {
+                device_id,
+                delta,
+                phase,
+                modifiers,
+            } => Some(MouseWheel {
+                device_id,
+                delta,
+                phase,
+                modifiers,
+            }),
+            #[allow(deprecated)]
+            MouseInput {
+                device_id,
+                state,
+                button,
+                modifiers,
+            } => Some(MouseInput {
+                device_id,
+                state,
+                button,
+                modifiers,
+            }),
+            TouchpadPressure {
+                device_id,
+                pressure,
+                stage,
+            } => Some(TouchpadPressure {
+                device_id,
+                pressure,
+                stage,
+            }),
+            AxisMotion {
+                device_id,
+                axis,
+                value,
+            } => Some(AxisMotion {
+                device_id,
+                axis,
+                value,
+            }),
+            Touch(touch) => Some(Touch(touch)),
+            ThemeChanged(theme) => Some(ThemeChanged(theme)),
+            ScaleFactorChanged { .. } => None,
+        }
+    }
+}
+
 /// Identifier of an input device.
 ///
 /// Whenever you receive an event arising from a particular input device, this event contains a `DeviceId` which
@@ -298,16 +472,6 @@ pub enum DeviceEvent {
 
     Key(KeyboardInput),
 
-    /// The keyboard modifiers have changed.
-    ///
-    /// This is tracked internally to avoid tracking errors arising from modifier key state changes when events from
-    /// this device are not being delivered to the application, e.g. due to keyboard focus being elsewhere.
-    ///
-    /// Platform-specific behavior:
-    /// - **Web**: This API is currently unimplemented on the web. This isn't by design - it's an
-    ///   issue, and it should get fixed - but it's the current state of the API.
-    ModifiersChanged(ModifiersState),
-
     Text {
         codepoint: char,
     },
@@ -336,7 +500,7 @@ pub struct KeyboardInput {
     ///
     /// This is tracked internally to avoid tracking errors arising from modifier key state changes when events from
     /// this device are not being delivered to the application, e.g. due to keyboard focus being elsewhere.
-    #[deprecated = "Deprecated in favor of DeviceEvent::ModifiersChanged"]
+    #[deprecated = "Deprecated in favor of WindowEvent::ModifiersChanged"]
     pub modifiers: ModifiersState,
 }
 
@@ -370,7 +534,7 @@ pub enum TouchPhase {
 pub struct Touch {
     pub device_id: DeviceId,
     pub phase: TouchPhase,
-    pub location: LogicalPosition,
+    pub location: PhysicalPosition<f64>,
     /// Describes how hard the screen was pressed. May be `None` if the platform
     /// does not support pressure sensitivity.
     ///
@@ -481,7 +645,7 @@ pub enum MouseScrollDelta {
     /// Scroll events are expressed as a PixelDelta if
     /// supported by the device (eg. a touchpad) and
     /// platform.
-    PixelDelta(LogicalPosition),
+    PixelDelta(LogicalPosition<f64>),
 }
 
 /// Symbolic name for a keyboard key.

src/event_loop.rs

@@ -143,7 +143,7 @@ impl<T> EventLoop<T> {
     #[inline]
     pub fn run<F>(self, event_handler: F) -> !
     where
-        F: 'static + FnMut(Event<T>, &EventLoopWindowTarget<T>, &mut ControlFlow),
+        F: 'static + FnMut(Event<'_, T>, &EventLoopWindowTarget<T>, &mut ControlFlow),
     {
         self.event_loop.run(event_handler)
     }
@@ -215,14 +215,10 @@ impl<T: 'static> fmt::Debug for EventLoopProxy<T> {
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
 pub struct EventLoopClosed<T>(pub T);
 
-impl<T: fmt::Debug> fmt::Display for EventLoopClosed<T> {
+impl<T> fmt::Display for EventLoopClosed<T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", error::Error::description(self))
+        f.write_str("Tried to wake up a closed `EventLoop`")
     }
 }
 
-impl<T: fmt::Debug> error::Error for EventLoopClosed<T> {
-    fn description(&self) -> &str {
-        "Tried to wake up a closed `EventLoop`"
-    }
-}
+impl<T: fmt::Debug> error::Error for EventLoopClosed<T> {}

src/icon.rs

@@ -1,4 +1,5 @@
-use std::{error::Error, fmt, mem};
+use crate::platform_impl::PlatformIcon;
+use std::{error::Error, fmt, io, mem};
 
 #[repr(C)]
 #[derive(Debug)]
@@ -11,7 +12,7 @@ pub(crate) struct Pixel {
 
 pub(crate) const PIXEL_SIZE: usize = mem::size_of::<Pixel>();
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Debug)]
 /// An error produced when using `Icon::from_rgba` with invalid arguments.
 pub enum BadIcon {
     /// Produced when the length of the `rgba` argument isn't divisible by 4, thus `rgba` can't be
@@ -25,72 +26,110 @@ pub enum BadIcon {
         width_x_height: usize,
         pixel_count: usize,
     },
+    /// Produced when underlying OS functionality failed to create the icon
+    OsError(io::Error),
 }
 
 impl fmt::Display for BadIcon {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let msg = match self {
-            &BadIcon::ByteCountNotDivisibleBy4 { byte_count } => format!(
+        match self {
+            BadIcon::ByteCountNotDivisibleBy4 { byte_count } => write!(f,
                 "The length of the `rgba` argument ({:?}) isn't divisible by 4, making it impossible to interpret as 32bpp RGBA pixels.",
                 byte_count,
             ),
-            &BadIcon::DimensionsVsPixelCount {
+            BadIcon::DimensionsVsPixelCount {
                 width,
                 height,
                 width_x_height,
                 pixel_count,
-            } => format!(
+            } => write!(f,
                 "The specified dimensions ({:?}x{:?}) don't match the number of pixels supplied by the `rgba` argument ({:?}). For those dimensions, the expected pixel count is {:?}.",
                 width, height, pixel_count, width_x_height,
             ),
-        };
-        write!(f, "{}", msg)
+            BadIcon::OsError(e) => write!(f, "OS error when instantiating the icon: {:?}", e),
+        }
     }
 }
 
 impl Error for BadIcon {
-    fn description(&self) -> &str {
-        "A valid icon cannot be created from these arguments"
-    }
-
-    fn cause(&self) -> Option<&dyn Error> {
+    fn source(&self) -> Option<&(dyn Error + 'static)> {
         Some(self)
     }
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
-/// An icon used for the window titlebar, taskbar, etc.
-pub struct Icon {
+pub(crate) struct RgbaIcon {
     pub(crate) rgba: Vec<u8>,
     pub(crate) width: u32,
     pub(crate) height: u32,
 }
 
+/// For platforms which don't have window icons (e.g. web)
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub(crate) struct NoIcon;
+
+#[allow(dead_code)] // These are not used on every platform
+mod constructors {
+    use super::*;
+
+    impl RgbaIcon {
+        /// Creates an `Icon` from 32bpp RGBA data.
+        ///
+        /// The length of `rgba` must be divisible by 4, and `width * height` must equal
+        /// `rgba.len() / 4`. Otherwise, this will return a `BadIcon` error.
+        pub fn from_rgba(rgba: Vec<u8>, width: u32, height: u32) -> Result<Self, BadIcon> {
+            if rgba.len() % PIXEL_SIZE != 0 {
+                return Err(BadIcon::ByteCountNotDivisibleBy4 {
+                    byte_count: rgba.len(),
+                });
+            }
+            let pixel_count = rgba.len() / PIXEL_SIZE;
+            if pixel_count != (width * height) as usize {
+                Err(BadIcon::DimensionsVsPixelCount {
+                    width,
+                    height,
+                    width_x_height: (width * height) as usize,
+                    pixel_count,
+                })
+            } else {
+                Ok(RgbaIcon {
+                    rgba,
+                    width,
+                    height,
+                })
+            }
+        }
+    }
+
+    impl NoIcon {
+        pub fn from_rgba(rgba: Vec<u8>, width: u32, height: u32) -> Result<Self, BadIcon> {
+            // Create the rgba icon anyway to validate the input
+            let _ = RgbaIcon::from_rgba(rgba, width, height)?;
+            Ok(NoIcon)
+        }
+    }
+}
+
+/// An icon used for the window titlebar, taskbar, etc.
+#[derive(Clone)]
+pub struct Icon {
+    pub(crate) inner: PlatformIcon,
+}
+
+impl fmt::Debug for Icon {
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
+        fmt::Debug::fmt(&self.inner, formatter)
+    }
+}
+
 impl Icon {
     /// Creates an `Icon` from 32bpp RGBA data.
     ///
     /// The length of `rgba` must be divisible by 4, and `width * height` must equal
     /// `rgba.len() / 4`. Otherwise, this will return a `BadIcon` error.
     pub fn from_rgba(rgba: Vec<u8>, width: u32, height: u32) -> Result<Self, BadIcon> {
-        if rgba.len() % PIXEL_SIZE != 0 {
-            return Err(BadIcon::ByteCountNotDivisibleBy4 {
-                byte_count: rgba.len(),
-            });
-        }
-        let pixel_count = rgba.len() / PIXEL_SIZE;
-        if pixel_count != (width * height) as usize {
-            Err(BadIcon::DimensionsVsPixelCount {
-                width,
-                height,
-                width_x_height: (width * height) as usize,
-                pixel_count,
-            })
-        } else {
-            Ok(Icon {
-                rgba,
-                width,
-                height,
-            })
-        }
+        Ok(Icon {
+            inner: PlatformIcon::from_rgba(rgba, width, height)?,
+        })
     }
 }

src/lib.rs

@@ -1,6 +1,6 @@
-//! Winit allows you to build a window on as many platforms as possible.
+//! Winit is a cross-platform window creation and event loop management library.
 //!
-//! # Building a window
+//! # Building windows
 //!
 //! Before you can build a [`Window`], you first need to build an [`EventLoop`]. This is done with the
 //! [`EventLoop::new()`] function.
@@ -15,26 +15,31 @@
 //!  - Calling [`Window::new(&event_loop)`][window_new].
 //!  - Calling [`let builder = WindowBuilder::new()`][window_builder_new] then [`builder.build(&event_loop)`][window_builder_build].
 //!
-//! The first way is the simplest way and will give you default values for everything.
-//!
-//! The second way allows you to customize the way your [`Window`] will look and behave by modifying
-//! the fields of the [`WindowBuilder`] object before you create the [`Window`].
+//! The first method is the simplest, and will give you default values for everything. The second
+//! method allows you to customize the way your [`Window`] will look and behave by modifying the
+//! fields of the [`WindowBuilder`] object before you create the [`Window`].
 //!
 //! # Event handling
 //!
 //! Once a [`Window`] has been created, it will generate different *events*. A [`Window`] object can
-//! generate a [`WindowEvent`] when certain things happen, like whenever the user moves their mouse
-//! or presses a key inside the [`Window`]. Devices can generate a [`DeviceEvent`] directly as well,
-//! which contains unfiltered event data that isn't specific to a certain window. Some user
-//! activity, like mouse movement, can generate both a [`WindowEvent`] *and* a [`DeviceEvent`]. You
-//! can also create and handle your own custom [`UserEvent`]s, if desired.
+//! generate [`WindowEvent`]s when certain input events occur, such as a cursor moving over the
+//! window or a key getting pressed while the window is focused. Devices can generate
+//! [`DeviceEvent`]s, which contain unfiltered event data that isn't specific to a certain window.
+//! Some user activity, like mouse movement, can generate both a [`WindowEvent`] *and* a
+//! [`DeviceEvent`]. You can also create and handle your own custom [`UserEvent`]s, if desired.
 //!
-//! Events can be retreived by using an [`EventLoop`]. A [`Window`] will send its events to the
-//! [`EventLoop`] object it was created with.
+//! You can retreive events by calling [`EventLoop::run`][event_loop_run]. This function will
+//! dispatch events for every [`Window`] that was created with that particular [`EventLoop`], and
+//! will run until the `control_flow` argument given to the closure is set to
+//! [`ControlFlow`]`::`[`Exit`], at which point [`Event`]`::`[`LoopDestroyed`] is emitted and the
+//! entire program terminates.
+//!
+//! Winit no longer uses a `EventLoop::poll_events() -> impl Iterator<Event>`-based event loop
+//! model, since that can't be implemented properly on web and mobile platforms and works poorly on
+//! most desktop platforms. However, this model can be re-implemented to an extent on desktops with
+//! [`EventLoopExtDesktop::run_return`]. See that method's documentation for more reasons about why
+//! it's discouraged, beyond mobile/web compatibility reasons.
 //!
-//! You do this by calling [`event_loop.run(...)`][event_loop_run]. This function will run forever
-//! unless `control_flow` is set to [`ControlFlow`]`::`[`Exit`], at which point [`Event`]`::`[`LoopDestroyed`]
-//! is emitted and the entire program terminates.
 //!
 //! ```no_run
 //! use winit::{
@@ -47,7 +52,23 @@
 //! let window = WindowBuilder::new().build(&event_loop).unwrap();
 //!
 //! event_loop.run(move |event, _, control_flow| {
+//!     // ControlFlow::Poll continuously runs the event loop, even if the OS hasn't
+//!     // dispatched any events. This is ideal for games and similar applications.
+//!     *control_flow = ControlFlow::Poll;
+//!
+//!     // ControlFlow::Wait pauses the event loop if no events are available to process.
+//!     // This is ideal for non-game applications that only update in response to user
+//!     // input, and uses significantly less power/CPU time than ControlFlow::Poll.
+//!     *control_flow = ControlFlow::Wait;
+//!
 //!     match event {
+//!         Event::WindowEvent {
+//!             event: WindowEvent::CloseRequested,
+//!             ..
+//!         } => {
+//!             println!("The close button was pressed; stopping");
+//!             *control_flow = ControlFlow::Exit
+//!         },
 //!         Event::MainEventsCleared => {
 //!             // Application update code.
 //!
@@ -61,40 +82,29 @@
 //!             // rendering in here allows the program to gracefully handle redraws requested
 //!             // by the OS.
 //!         },
-//!         Event::WindowEvent {
-//!             event: WindowEvent::CloseRequested,
-//!             ..
-//!         } => {
-//!             println!("The close button was pressed; stopping");
-//!             *control_flow = ControlFlow::Exit
-//!         },
-//!         // ControlFlow::Poll continuously runs the event loop, even if the OS hasn't
-//!         // dispatched any events. This is ideal for games and similar applications.
-//!         _ => *control_flow = ControlFlow::Poll,
-//!         // ControlFlow::Wait pauses the event loop if no events are available to process.
-//!         // This is ideal for non-game applications that only update in response to user
-//!         // input, and uses significantly less power/CPU time than ControlFlow::Poll.
-//!         // _ => *control_flow = ControlFlow::Wait,
+//!         _ => ()
 //!     }
 //! });
 //! ```
 //!
-//! If you use multiple [`Window`]s, [`Event`]`::`[`WindowEvent`] has a member named `window_id`. You can
-//! compare it with the value returned by the [`id()`][window_id_fn] method of [`Window`] in order to know which
-//! [`Window`] has received the event.
+//! [`Event`]`::`[`WindowEvent`] has a [`WindowId`] member. In multi-window environments, it should be
+//! compared to the value returned by [`Window::id()`][window_id_fn] to determine which [`Window`]
+//! dispatched the event.
 //!
 //! # Drawing on the window
 //!
-//! Winit doesn't provide any function that allows drawing on a [`Window`]. However it allows you to
+//! Winit doesn't directly provide any methods for drawing on a [`Window`]. However it allows you to
 //! retrieve the raw handle of the window (see the [`platform`] module), which in turn allows you
-//! to create an OpenGL/Vulkan/DirectX/Metal/etc. context that will draw on the [`Window`].
+//! to create an OpenGL/Vulkan/DirectX/Metal/etc. context that can be used to render graphics.
 //!
 //! [`EventLoop`]: event_loop::EventLoop
+//! [`EventLoopExtDesktop::run_return`]: ./platform/desktop/trait.EventLoopExtDesktop.html#tymethod.run_return
 //! [`EventLoop::new()`]: event_loop::EventLoop::new
 //! [event_loop_run]: event_loop::EventLoop::run
 //! [`ControlFlow`]: event_loop::ControlFlow
 //! [`Exit`]: event_loop::ControlFlow::Exit
 //! [`Window`]: window::Window
+//! [`WindowId`]: window::WindowId
 //! [`WindowBuilder`]: window::WindowBuilder
 //! [window_new]: window::Window::new
 //! [window_builder_new]: window::WindowBuilder::new
@@ -113,6 +123,7 @@
 #[allow(unused_imports)]
 #[macro_use]
 extern crate lazy_static;
+#[allow(unused_imports)]
 #[macro_use]
 extern crate log;
 #[cfg(feature = "serde")]

src/monitor.rs

@@ -58,7 +58,7 @@ impl Ord for VideoMode {
 impl VideoMode {
     /// Returns the resolution of this video mode.
     #[inline]
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         self.video_mode.size()
     }
 
@@ -133,7 +133,7 @@ impl MonitorHandle {
     ///
     /// - **Web:** Always returns (0,0)
     #[inline]
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         self.inner.size()
     }
 
@@ -144,22 +144,22 @@ impl MonitorHandle {
     ///
     /// - **Web:** Always returns (0,0)
     #[inline]
-    pub fn position(&self) -> PhysicalPosition {
+    pub fn position(&self) -> PhysicalPosition<i32> {
         self.inner.position()
     }
 
-    /// Returns the DPI factor that can be used to map logical pixels to physical pixels, and vice versa.
+    /// Returns the scale factor that can be used to map logical pixels to physical pixels, and vice versa.
     ///
     /// See the [`dpi`](crate::dpi) module for more information.
     ///
     /// ## Platform-specific
     ///
-    /// - **X11:** Can be overridden using the `WINIT_HIDPI_FACTOR` environment variable.
+    /// - **X11:** Can be overridden using the `WINIT_X11_SCALE_FACTOR` environment variable.
     /// - **Android:** Always returns 1.0.
     /// - **Web:** Always returns 1.0
     #[inline]
-    pub fn hidpi_factor(&self) -> f64 {
-        self.inner.hidpi_factor()
+    pub fn scale_factor(&self) -> f64 {
+        self.inner.scale_factor()
     }
 
     /// Returns all fullscreen video modes supported by this monitor.

src/platform/desktop.rs

@@ -30,7 +30,11 @@ pub trait EventLoopExtDesktop {
     /// You are strongly encouraged to use `run`, unless the use of this is absolutely necessary.
     fn run_return<F>(&mut self, event_handler: F)
     where
-        F: FnMut(Event<Self::UserEvent>, &EventLoopWindowTarget<Self::UserEvent>, &mut ControlFlow);
+        F: FnMut(
+            Event<'_, Self::UserEvent>,
+            &EventLoopWindowTarget<Self::UserEvent>,
+            &mut ControlFlow,
+        );
 }
 
 impl<T> EventLoopExtDesktop for EventLoop<T> {
@@ -38,7 +42,11 @@ impl<T> EventLoopExtDesktop for EventLoop<T> {
 
     fn run_return<F>(&mut self, event_handler: F)
     where
-        F: FnMut(Event<T>, &EventLoopWindowTarget<T>, &mut ControlFlow),
+        F: FnMut(
+            Event<'_, Self::UserEvent>,
+            &EventLoopWindowTarget<Self::UserEvent>,
+            &mut ControlFlow,
+        ),
     {
         self.event_loop.run_return(event_handler)
     }

src/platform/ios.rs

@@ -43,14 +43,14 @@ pub trait WindowExtIOS {
     /// [`UIView`]: https://developer.apple.com/documentation/uikit/uiview?language=objc
     fn ui_view(&self) -> *mut c_void;
 
-    /// Sets the [`contentScaleFactor`] of the underlying [`UIWindow`] to `hidpi_factor`.
+    /// Sets the [`contentScaleFactor`] of the underlying [`UIWindow`] to `scale_factor`.
     ///
     /// The default value is device dependent, and it's recommended GLES or Metal applications set
-    /// this to [`MonitorHandle::hidpi_factor()`].
+    /// this to [`MonitorHandle::scale_factor()`].
     ///
     /// [`UIWindow`]: https://developer.apple.com/documentation/uikit/uiwindow?language=objc
     /// [`contentScaleFactor`]: https://developer.apple.com/documentation/uikit/uiview/1622657-contentscalefactor?language=objc
-    fn set_hidpi_factor(&self, hidpi_factor: f64);
+    fn set_scale_factor(&self, scale_factor: f64);
 
     /// Sets the valid orientations for the [`Window`].
     ///
@@ -113,8 +113,8 @@ impl WindowExtIOS for Window {
     }
 
     #[inline]
-    fn set_hidpi_factor(&self, hidpi_factor: f64) {
-        self.window.set_hidpi_factor(hidpi_factor)
+    fn set_scale_factor(&self, scale_factor: f64) {
+        self.window.set_scale_factor(scale_factor)
     }
 
     #[inline]
@@ -148,14 +148,14 @@ pub trait WindowBuilderExtIOS {
     /// [`UIView`]: https://developer.apple.com/documentation/uikit/uiview?language=objc
     fn with_root_view_class(self, root_view_class: *const c_void) -> WindowBuilder;
 
-    /// Sets the [`contentScaleFactor`] of the underlying [`UIWindow`] to `hidpi_factor`.
+    /// Sets the [`contentScaleFactor`] of the underlying [`UIWindow`] to `scale_factor`.
     ///
     /// The default value is device dependent, and it's recommended GLES or Metal applications set
-    /// this to [`MonitorHandle::hidpi_factor()`].
+    /// this to [`MonitorHandle::scale_factor()`].
     ///
     /// [`UIWindow`]: https://developer.apple.com/documentation/uikit/uiwindow?language=objc
     /// [`contentScaleFactor`]: https://developer.apple.com/documentation/uikit/uiview/1622657-contentscalefactor?language=objc
-    fn with_hidpi_factor(self, hidpi_factor: f64) -> WindowBuilder;
+    fn with_scale_factor(self, scale_factor: f64) -> WindowBuilder;
 
     /// Sets the valid orientations for the [`Window`].
     ///
@@ -204,8 +204,8 @@ impl WindowBuilderExtIOS for WindowBuilder {
     }
 
     #[inline]
-    fn with_hidpi_factor(mut self, hidpi_factor: f64) -> WindowBuilder {
-        self.platform_specific.hidpi_factor = Some(hidpi_factor);
+    fn with_scale_factor(mut self, scale_factor: f64) -> WindowBuilder {
+        self.platform_specific.scale_factor = Some(scale_factor);
         self
     }
 

src/platform/macos.rs

@@ -4,6 +4,7 @@ use std::os::raw::c_void;
 
 use crate::{
     dpi::LogicalSize,
+    event_loop::EventLoopWindowTarget,
     monitor::MonitorHandle,
     window::{Window, WindowBuilder},
 };
@@ -128,7 +129,7 @@ pub trait WindowBuilderExtMacOS {
     /// Makes the window content appear behind the titlebar.
     fn with_fullsize_content_view(self, fullsize_content_view: bool) -> WindowBuilder;
     /// Build window with `resizeIncrements` property. Values must not be 0.
-    fn with_resize_increments(self, increments: LogicalSize) -> WindowBuilder;
+    fn with_resize_increments(self, increments: LogicalSize<f64>) -> WindowBuilder;
     fn with_disallow_hidpi(self, disallow_hidpi: bool) -> WindowBuilder;
 }
 
@@ -179,7 +180,7 @@ impl WindowBuilderExtMacOS for WindowBuilder {
     }
 
     #[inline]
-    fn with_resize_increments(mut self, increments: LogicalSize) -> WindowBuilder {
+    fn with_resize_increments(mut self, increments: LogicalSize<f64>) -> WindowBuilder {
         self.platform_specific.resize_increments = Some(increments.into());
         self
     }
@@ -209,3 +210,17 @@ impl MonitorHandleExtMacOS for MonitorHandle {
         self.inner.ns_screen().map(|s| s as *mut c_void)
     }
 }
+
+/// Additional methods on `EventLoopWindowTarget` that are specific to macOS.
+pub trait EventLoopWindowTargetExtMacOS {
+    /// Hide the entire application. In most applications this is typically triggered with Command-H.
+    fn hide_application(&self);
+}
+
+impl<T> EventLoopWindowTargetExtMacOS for EventLoopWindowTarget<T> {
+    fn hide_application(&self) {
+        let cls = objc::runtime::Class::get("NSApplication").unwrap();
+        let app: cocoa::base::id = unsafe { msg_send![cls, sharedApplication] };
+        unsafe { msg_send![app, hide: 0] }
+    }
+}

src/platform/unix.rs

@@ -2,10 +2,10 @@
 
 use std::{os::raw, ptr, sync::Arc};
 
-use smithay_client_toolkit::window::{ButtonState, Theme};
+use smithay_client_toolkit::window::{ButtonState as SCTKButtonState, Theme as SCTKTheme};
 
 use crate::{
-    dpi::LogicalSize,
+    dpi::Size,
     event_loop::{EventLoop, EventLoopWindowTarget},
     monitor::MonitorHandle,
     window::{Window, WindowBuilder},
@@ -23,74 +23,6 @@ pub use crate::platform_impl::x11;
 
 pub use crate::platform_impl::{x11::util::WindowType as XWindowType, XNotSupported};
 
-/// Theme for wayland client side decorations
-///
-/// Colors must be in ARGB8888 format
-pub struct WaylandTheme {
-    /// Primary color when the window is focused
-    pub primary_active: [u8; 4],
-    /// Primary color when the window is unfocused
-    pub primary_inactive: [u8; 4],
-    /// Secondary color when the window is focused
-    pub secondary_active: [u8; 4],
-    /// Secondary color when the window is unfocused
-    pub secondary_inactive: [u8; 4],
-    /// Close button color when hovered over
-    pub close_button_hovered: [u8; 4],
-    /// Close button color
-    pub close_button: [u8; 4],
-    /// Close button color when hovered over
-    pub maximize_button_hovered: [u8; 4],
-    /// Maximize button color
-    pub maximize_button: [u8; 4],
-    /// Minimize button color when hovered over
-    pub minimize_button_hovered: [u8; 4],
-    /// Minimize button color
-    pub minimize_button: [u8; 4],
-}
-
-struct WaylandThemeObject(WaylandTheme);
-
-impl Theme for WaylandThemeObject {
-    fn get_primary_color(&self, active: bool) -> [u8; 4] {
-        if active {
-            self.0.primary_active
-        } else {
-            self.0.primary_inactive
-        }
-    }
-
-    // Used for division line
-    fn get_secondary_color(&self, active: bool) -> [u8; 4] {
-        if active {
-            self.0.secondary_active
-        } else {
-            self.0.secondary_inactive
-        }
-    }
-
-    fn get_close_button_color(&self, state: ButtonState) -> [u8; 4] {
-        match state {
-            ButtonState::Hovered => self.0.close_button_hovered,
-            _ => self.0.close_button,
-        }
-    }
-
-    fn get_maximize_button_color(&self, state: ButtonState) -> [u8; 4] {
-        match state {
-            ButtonState::Hovered => self.0.maximize_button_hovered,
-            _ => self.0.maximize_button,
-        }
-    }
-
-    fn get_minimize_button_color(&self, state: ButtonState) -> [u8; 4] {
-        match state {
-            ButtonState::Hovered => self.0.minimize_button_hovered,
-            _ => self.0.minimize_button,
-        }
-    }
-}
-
 /// Additional methods on `EventLoopWindowTarget` that are specific to Unix.
 pub trait EventLoopWindowTargetExtUnix {
     /// True if the `EventLoopWindowTarget` uses Wayland.
@@ -275,7 +207,7 @@ pub trait WindowExtUnix {
     fn wayland_display(&self) -> Option<*mut raw::c_void>;
 
     /// Sets the color theme of the client side window decorations on wayland
-    fn set_wayland_theme(&self, theme: WaylandTheme);
+    fn set_wayland_theme<T: Theme>(&self, theme: T);
 
     /// Check if the window is ready for drawing
     ///
@@ -353,9 +285,9 @@ impl WindowExtUnix for Window {
     }
 
     #[inline]
-    fn set_wayland_theme(&self, theme: WaylandTheme) {
+    fn set_wayland_theme<T: Theme>(&self, theme: T) {
         match self.window {
-            LinuxWindow::Wayland(ref w) => w.set_theme(WaylandThemeObject(theme)),
+            LinuxWindow::Wayland(ref w) => w.set_theme(WaylandTheme(theme)),
             _ => {}
         }
     }
@@ -380,9 +312,9 @@ pub trait WindowBuilderExtUnix {
     /// Build window with `_GTK_THEME_VARIANT` hint set to the specified value. Currently only relevant on X11.
     fn with_gtk_theme_variant(self, variant: String) -> Self;
     /// Build window with resize increment hint. Only implemented on X11.
-    fn with_resize_increments(self, increments: LogicalSize) -> Self;
+    fn with_resize_increments<S: Into<Size>>(self, increments: S) -> Self;
     /// Build window with base size hint. Only implemented on X11.
-    fn with_base_size(self, base_size: LogicalSize) -> Self;
+    fn with_base_size<S: Into<Size>>(self, base_size: S) -> Self;
 
     /// Build window with a given application ID. It should match the `.desktop` file distributed with
     /// your program. Only relevant on Wayland.
@@ -431,13 +363,13 @@ impl WindowBuilderExtUnix for WindowBuilder {
     }
 
     #[inline]
-    fn with_resize_increments(mut self, increments: LogicalSize) -> Self {
+    fn with_resize_increments<S: Into<Size>>(mut self, increments: S) -> Self {
         self.platform_specific.resize_increments = Some(increments.into());
         self
     }
 
     #[inline]
-    fn with_base_size(mut self, base_size: LogicalSize) -> Self {
+    fn with_base_size<S: Into<Size>>(mut self, base_size: S) -> Self {
         self.platform_specific.base_size = Some(base_size.into());
         self
     }
@@ -461,3 +393,97 @@ impl MonitorHandleExtUnix for MonitorHandle {
         self.inner.native_identifier()
     }
 }
+
+/// Wrapper for implementing SCTK's theme trait.
+struct WaylandTheme<T: Theme>(T);
+
+pub trait Theme: Send + 'static {
+    /// Primary color of the scheme.
+    fn primary_color(&self, window_active: bool) -> [u8; 4];
+
+    /// Secondary color of the scheme.
+    fn secondary_color(&self, window_active: bool) -> [u8; 4];
+
+    /// Color for the close button.
+    fn close_button_color(&self, status: ButtonState) -> [u8; 4];
+
+    /// Icon color for the close button, defaults to the secondary color.
+    #[allow(unused_variables)]
+    fn close_button_icon_color(&self, status: ButtonState) -> [u8; 4] {
+        self.secondary_color(true)
+    }
+
+    /// Background color for the maximize button.
+    fn maximize_button_color(&self, status: ButtonState) -> [u8; 4];
+
+    /// Icon color for the maximize button, defaults to the secondary color.
+    #[allow(unused_variables)]
+    fn maximize_button_icon_color(&self, status: ButtonState) -> [u8; 4] {
+        self.secondary_color(true)
+    }
+
+    /// Background color for the minimize button.
+    fn minimize_button_color(&self, status: ButtonState) -> [u8; 4];
+
+    /// Icon color for the minimize button, defaults to the secondary color.
+    #[allow(unused_variables)]
+    fn minimize_button_icon_color(&self, status: ButtonState) -> [u8; 4] {
+        self.secondary_color(true)
+    }
+}
+
+impl<T: Theme> SCTKTheme for WaylandTheme<T> {
+    fn get_primary_color(&self, active: bool) -> [u8; 4] {
+        self.0.primary_color(active)
+    }
+
+    fn get_secondary_color(&self, active: bool) -> [u8; 4] {
+        self.0.secondary_color(active)
+    }
+
+    fn get_close_button_color(&self, status: SCTKButtonState) -> [u8; 4] {
+        self.0.close_button_color(ButtonState::from_sctk(status))
+    }
+
+    fn get_close_button_icon_color(&self, status: SCTKButtonState) -> [u8; 4] {
+        self.0
+            .close_button_icon_color(ButtonState::from_sctk(status))
+    }
+
+    fn get_maximize_button_color(&self, status: SCTKButtonState) -> [u8; 4] {
+        self.0.maximize_button_color(ButtonState::from_sctk(status))
+    }
+
+    fn get_maximize_button_icon_color(&self, status: SCTKButtonState) -> [u8; 4] {
+        self.0
+            .maximize_button_icon_color(ButtonState::from_sctk(status))
+    }
+
+    fn get_minimize_button_color(&self, status: SCTKButtonState) -> [u8; 4] {
+        self.0.minimize_button_color(ButtonState::from_sctk(status))
+    }
+
+    fn get_minimize_button_icon_color(&self, status: SCTKButtonState) -> [u8; 4] {
+        self.0
+            .minimize_button_icon_color(ButtonState::from_sctk(status))
+    }
+}
+
+pub enum ButtonState {
+    /// Button is being hovered over by pointer.
+    Hovered,
+    /// Button is not being hovered over by pointer.
+    Idle,
+    /// Button is disabled.
+    Disabled,
+}
+
+impl ButtonState {
+    fn from_sctk(button_state: SCTKButtonState) -> Self {
+        match button_state {
+            SCTKButtonState::Hovered => Self::Hovered,
+            SCTKButtonState::Idle => Self::Idle,
+            SCTKButtonState::Disabled => Self::Disabled,
+        }
+    }
+}

src/platform/web.rs

@@ -3,7 +3,10 @@
 //! The web target does not automatically insert the canvas element object into the web page, to
 //! allow end users to determine how the page should be laid out. Use the `WindowExtStdweb` or
 //! `WindowExtWebSys` traits (depending on your web backend) to retrieve the canvas from the
-//! Window.
+//! Window. Alternatively, use the `WindowBuilderExtStdweb` or `WindowBuilderExtWebSys` to provide
+//! your own canvas.
+
+use crate::window::WindowBuilder;
 
 #[cfg(feature = "stdweb")]
 use stdweb::web::html_element::CanvasElement;
@@ -11,6 +14,9 @@ use stdweb::web::html_element::CanvasElement;
 #[cfg(feature = "stdweb")]
 pub trait WindowExtStdweb {
     fn canvas(&self) -> CanvasElement;
+
+    /// Whether the browser reports the preferred color scheme to be "dark".
+    fn is_dark_mode(&self) -> bool;
 }
 
 #[cfg(feature = "web-sys")]
@@ -19,4 +25,35 @@ use web_sys::HtmlCanvasElement;
 #[cfg(feature = "web-sys")]
 pub trait WindowExtWebSys {
     fn canvas(&self) -> HtmlCanvasElement;
+
+    /// Whether the browser reports the preferred color scheme to be "dark".
+    fn is_dark_mode(&self) -> bool;
+}
+
+#[cfg(feature = "stdweb")]
+pub trait WindowBuilderExtStdweb {
+    fn with_canvas(self, canvas: Option<CanvasElement>) -> Self;
+}
+
+#[cfg(feature = "stdweb")]
+impl WindowBuilderExtStdweb for WindowBuilder {
+    fn with_canvas(mut self, canvas: Option<CanvasElement>) -> Self {
+        self.platform_specific.canvas = canvas;
+
+        self
+    }
+}
+
+#[cfg(feature = "web-sys")]
+pub trait WindowBuilderExtWebSys {
+    fn with_canvas(self, canvas: Option<HtmlCanvasElement>) -> Self;
+}
+
+#[cfg(feature = "web-sys")]
+impl WindowBuilderExtWebSys for WindowBuilder {
+    fn with_canvas(mut self, canvas: Option<HtmlCanvasElement>) -> Self {
+        self.platform_specific.canvas = canvas;
+
+        self
+    }
 }

src/platform/windows.rs

@@ -1,16 +1,19 @@
 #![cfg(target_os = "windows")]
 
 use std::os::raw::c_void;
+use std::path::Path;
 
 use libc;
+use winapi::shared::minwindef::WORD;
 use winapi::shared::windef::HWND;
 
 use crate::{
+    dpi::PhysicalSize,
     event::DeviceId,
     event_loop::EventLoop,
     monitor::MonitorHandle,
-    platform_impl::EventLoop as WindowsEventLoop,
-    window::{Icon, Window, WindowBuilder},
+    platform_impl::{EventLoop as WindowsEventLoop, WinIcon},
+    window::{BadIcon, Icon, Window, WindowBuilder},
 };
 
 /// Additional methods on `EventLoop` that are specific to Windows.
@@ -171,3 +174,40 @@ impl DeviceIdExtWindows for DeviceId {
         self.0.persistent_identifier()
     }
 }
+
+/// Additional methods on `Icon` that are specific to Windows.
+pub trait IconExtWindows: Sized {
+    /// Create an icon from a file path.
+    ///
+    /// Specify `size` to load a specific icon size from the file, or `None` to load the default
+    /// icon size from the file.
+    ///
+    /// In cases where the specified size does not exist in the file, Windows may perform scaling
+    /// to get an icon of the desired size.
+    fn from_path<P: AsRef<Path>>(path: P, size: Option<PhysicalSize<u32>>)
+        -> Result<Self, BadIcon>;
+
+    /// Create an icon from a resource embedded in this executable or library.
+    ///
+    /// Specify `size` to load a specific icon size from the file, or `None` to load the default
+    /// icon size from the file.
+    ///
+    /// In cases where the specified size does not exist in the file, Windows may perform scaling
+    /// to get an icon of the desired size.
+    fn from_resource(ordinal: WORD, size: Option<PhysicalSize<u32>>) -> Result<Self, BadIcon>;
+}
+
+impl IconExtWindows for Icon {
+    fn from_path<P: AsRef<Path>>(
+        path: P,
+        size: Option<PhysicalSize<u32>>,
+    ) -> Result<Self, BadIcon> {
+        let win_icon = WinIcon::from_path(path, size)?;
+        Ok(Icon { inner: win_icon })
+    }
+
+    fn from_resource(ordinal: WORD, size: Option<PhysicalSize<u32>>) -> Result<Self, BadIcon> {
+        let win_icon = WinIcon::from_resource(ordinal, size)?;
+        Ok(Icon { inner: win_icon })
+    }
+}

src/platform_impl/android/mod.rs

@@ -22,6 +22,8 @@ use crate::{
 use raw_window_handle::{android::AndroidHandle, RawWindowHandle};
 use CreationError::OsError;
 
+pub(crate) use crate::icon::NoIcon as PlatformIcon;
+
 pub type OsError = std::io::Error;
 
 pub struct EventLoop {
@@ -61,10 +63,10 @@ impl EventLoop {
         while let Ok(event) = self.event_rx.try_recv() {
             let e = match event {
                 android_glue::Event::EventMotion(motion) => {
-                    let dpi_factor = MonitorHandle.hidpi_factor();
+                    let scale_factor = MonitorHandle.scale_factor();
                     let location = LogicalPosition::from_physical(
                         (motion.x as f64, motion.y as f64),
-                        dpi_factor,
+                        scale_factor,
                     );
                     Some(Event::WindowEvent {
                         window_id: RootWindowId(WindowId),
@@ -102,9 +104,9 @@ impl EventLoop {
                     if native_window.is_null() {
                         None
                     } else {
-                        let dpi_factor = MonitorHandle.hidpi_factor();
+                        let scale_factor = MonitorHandle.scale_factor();
                         let physical_size = MonitorHandle.size();
-                        let size = LogicalSize::from_physical(physical_size, dpi_factor);
+                        let size = LogicalSize::from_physical(physical_size, scale_factor);
                         Some(Event::WindowEvent {
                             window_id: RootWindowId(WindowId),
                             event: WindowEvent::Resized(size),
@@ -193,16 +195,16 @@ impl fmt::Debug for MonitorHandle {
         #[derive(Debug)]
         struct MonitorHandle {
             name: Option<String>,
-            dimensions: PhysicalSize,
-            position: PhysicalPosition,
-            hidpi_factor: f64,
+            dimensions: PhysicalSize<u32>,
+            position: PhysicalPosition<i32>,
+            scale_factor: f64,
         }
 
         let monitor_id_proxy = MonitorHandle {
             name: self.name(),
             dimensions: self.size(),
             position: self.outer_position(),
-            hidpi_factor: self.hidpi_factor(),
+            scale_factor: self.scale_factor(),
         };
 
         monitor_id_proxy.fmt(f)
@@ -216,7 +218,7 @@ impl MonitorHandle {
     }
 
     #[inline]
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         unsafe {
             let window = android_glue::native_window();
             (
@@ -228,13 +230,13 @@ impl MonitorHandle {
     }
 
     #[inline]
-    pub fn outer_position(&self) -> PhysicalPosition {
+    pub fn outer_position(&self) -> PhysicalPosition<i32> {
         // Android assumes single screen
         (0, 0).into()
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f64 {
+    pub fn scale_factor(&self) -> f64 {
         1.0
     }
 }
@@ -283,29 +285,29 @@ impl Window {
     }
 
     #[inline]
-    pub fn outer_position(&self) -> Option<LogicalPosition> {
+    pub fn outer_position(&self) -> Option<LogicalPosition<f64>> {
         // N/A
         None
     }
 
     #[inline]
-    pub fn inner_position(&self) -> Option<LogicalPosition> {
+    pub fn inner_position(&self) -> Option<LogicalPosition<f64>> {
         // N/A
         None
     }
 
     #[inline]
-    pub fn set_outer_position(&self, _position: LogicalPosition) {
+    pub fn set_outer_position(&self, _position: LogicalPosition<f64>) {
         // N/A
     }
 
     #[inline]
-    pub fn set_min_inner_size(&self, _dimensions: Option<LogicalSize>) {
+    pub fn set_min_inner_size(&self, _dimensions: Option<LogicalSize<f64>>) {
         // N/A
     }
 
     #[inline]
-    pub fn set_max_inner_size(&self, _dimensions: Option<LogicalSize>) {
+    pub fn set_max_inner_size(&self, _dimensions: Option<LogicalSize<f64>>) {
         // N/A
     }
 
@@ -315,29 +317,29 @@ impl Window {
     }
 
     #[inline]
-    pub fn inner_size(&self) -> Option<LogicalSize> {
+    pub fn inner_size(&self) -> Option<LogicalSize<f64>> {
         if self.native_window.is_null() {
             None
         } else {
-            let dpi_factor = self.hidpi_factor();
+            let scale_factor = self.scale_factor();
             let physical_size = self.current_monitor().size();
-            Some(LogicalSize::from_physical(physical_size, dpi_factor))
+            Some(LogicalSize::from_physical(physical_size, scale_factor))
         }
     }
 
     #[inline]
-    pub fn outer_size(&self) -> Option<LogicalSize> {
+    pub fn outer_size(&self) -> Option<LogicalSize<f64>> {
         self.inner_size()
     }
 
     #[inline]
-    pub fn set_inner_size(&self, _size: LogicalSize) {
+    pub fn set_inner_size(&self, _size: LogicalSize<f64>) {
         // N/A
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f64 {
-        self.current_monitor().hidpi_factor()
+    pub fn scale_factor(&self) -> f64 {
+        self.current_monitor().scale_factor()
     }
 
     #[inline]
@@ -356,7 +358,10 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, _position: LogicalPosition) -> Result<(), ExternalError> {
+    pub fn set_cursor_position(
+        &self,
+        _position: LogicalPosition<f64>,
+    ) -> Result<(), ExternalError> {
         Err(ExternalError::NotSupported(NotSupportedError::new()))
     }
 
@@ -400,7 +405,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_position(&self, _spot: LogicalPosition) {
+    pub fn set_ime_position(&self, _spot: LogicalPosition<f64>) {
         // N/A
     }
 

src/platform_impl/ios/app_state.rs

@@ -12,15 +12,16 @@ use std::{
 use objc::runtime::{BOOL, YES};
 
 use crate::{
-    event::{Event, StartCause},
+    dpi::LogicalSize,
+    event::{Event, StartCause, WindowEvent},
     event_loop::ControlFlow,
     platform_impl::platform::{
-        event_loop::{EventHandler, Never},
+        event_loop::{EventHandler, EventProxy, EventWrapper, Never},
         ffi::{
             id, kCFRunLoopCommonModes, CFAbsoluteTimeGetCurrent, CFRelease, CFRunLoopAddTimer,
             CFRunLoopGetMain, CFRunLoopRef, CFRunLoopTimerCreate, CFRunLoopTimerInvalidate,
-            CFRunLoopTimerRef, CFRunLoopTimerSetNextFireDate, NSInteger, NSOperatingSystemVersion,
-            NSUInteger,
+            CFRunLoopTimerRef, CFRunLoopTimerSetNextFireDate, CGRect, CGSize, NSInteger,
+            NSOperatingSystemVersion, NSUInteger,
         },
     },
     window::WindowId as RootWindowId,
@@ -45,11 +46,11 @@ enum UserCallbackTransitionResult<'a> {
         processing_redraws: bool,
     },
     ReentrancyPrevented {
-        queued_events: &'a mut Vec<Event<Never>>,
+        queued_events: &'a mut Vec<EventWrapper>,
     },
 }
 
-impl Event<Never> {
+impl Event<'static, Never> {
     fn is_redraw(&self) -> bool {
         if let Event::RedrawRequested(_) = self {
             true
@@ -65,12 +66,12 @@ impl Event<Never> {
 enum AppStateImpl {
     NotLaunched {
         queued_windows: Vec<id>,
-        queued_events: Vec<Event<Never>>,
+        queued_events: Vec<EventWrapper>,
         queued_gpu_redraws: HashSet<id>,
     },
     Launching {
         queued_windows: Vec<id>,
-        queued_events: Vec<Event<Never>>,
+        queued_events: Vec<EventWrapper>,
         queued_event_handler: Box<dyn EventHandler>,
         queued_gpu_redraws: HashSet<id>,
     },
@@ -81,7 +82,7 @@ enum AppStateImpl {
     },
     // special state to deal with reentrancy and prevent mutable aliasing.
     InUserCallback {
-        queued_events: Vec<Event<Never>>,
+        queued_events: Vec<EventWrapper>,
         queued_gpu_redraws: HashSet<id>,
     },
     ProcessingRedraws {
@@ -222,7 +223,7 @@ impl AppState {
         });
     }
 
-    fn did_finish_launching_transition(&mut self) -> (Vec<id>, Vec<Event<Never>>) {
+    fn did_finish_launching_transition(&mut self) -> (Vec<id>, Vec<EventWrapper>) {
         let (windows, events, event_handler, queued_gpu_redraws) = match self.take_state() {
             AppStateImpl::Launching {
                 queued_windows,
@@ -245,7 +246,7 @@ impl AppState {
         (windows, events)
     }
 
-    fn wakeup_transition(&mut self) -> Option<Event<Never>> {
+    fn wakeup_transition(&mut self) -> Option<EventWrapper> {
         // before `AppState::did_finish_launching` is called, pretend there is no running
         // event loop.
         if !self.has_launched() {
@@ -258,7 +259,10 @@ impl AppState {
                 AppStateImpl::PollFinished {
                     waiting_event_handler,
                 },
-            ) => (waiting_event_handler, Event::NewEvents(StartCause::Poll)),
+            ) => (
+                waiting_event_handler,
+                EventWrapper::StaticEvent(Event::NewEvents(StartCause::Poll)),
+            ),
             (
                 ControlFlow::Wait,
                 AppStateImpl::Waiting {
@@ -267,10 +271,10 @@ impl AppState {
                 },
             ) => (
                 waiting_event_handler,
-                Event::NewEvents(StartCause::WaitCancelled {
+                EventWrapper::StaticEvent(Event::NewEvents(StartCause::WaitCancelled {
                     start,
                     requested_resume: None,
-                }),
+                })),
             ),
             (
                 ControlFlow::WaitUntil(requested_resume),
@@ -280,15 +284,15 @@ impl AppState {
                 },
             ) => {
                 let event = if Instant::now() >= requested_resume {
-                    Event::NewEvents(StartCause::ResumeTimeReached {
+                    EventWrapper::StaticEvent(Event::NewEvents(StartCause::ResumeTimeReached {
                         start,
                         requested_resume,
-                    })
+                    }))
                 } else {
-                    Event::NewEvents(StartCause::WaitCancelled {
+                    EventWrapper::StaticEvent(Event::NewEvents(StartCause::WaitCancelled {
                         start,
                         requested_resume: Some(requested_resume),
-                    })
+                    }))
                 };
                 (waiting_event_handler, event)
             }
@@ -587,7 +591,10 @@ pub unsafe fn did_finish_launching() {
 
     let (windows, events) = AppState::get_mut().did_finish_launching_transition();
 
-    let events = std::iter::once(Event::NewEvents(StartCause::Init)).chain(events);
+    let events = std::iter::once(EventWrapper::StaticEvent(Event::NewEvents(
+        StartCause::Init,
+    )))
+    .chain(events);
     handle_nonuser_events(events);
 
     // the above window dance hack, could possibly trigger new windows to be created.
@@ -616,12 +623,12 @@ pub unsafe fn handle_wakeup_transition() {
 }
 
 // requires main thread
-pub unsafe fn handle_nonuser_event(event: Event<Never>) {
+pub unsafe fn handle_nonuser_event(event: EventWrapper) {
     handle_nonuser_events(std::iter::once(event))
 }
 
 // requires main thread
-pub unsafe fn handle_nonuser_events<I: IntoIterator<Item = Event<Never>>>(events: I) {
+pub unsafe fn handle_nonuser_events<I: IntoIterator<Item = EventWrapper>>(events: I) {
     let mut this = AppState::get_mut();
     let (mut event_handler, active_control_flow, processing_redraws) =
         match this.try_user_callback_transition() {
@@ -638,16 +645,23 @@ pub unsafe fn handle_nonuser_events<I: IntoIterator<Item = Event<Never>>>(events
     let mut control_flow = this.control_flow;
     drop(this);
 
-    for event in events {
-        if !processing_redraws && event.is_redraw() {
-            log::info!("processing `RedrawRequested` during the main event loop");
-        } else if processing_redraws && !event.is_redraw() {
-            log::warn!(
-                "processing non `RedrawRequested` event after the main event loop: {:#?}",
-                event
-            );
+    for wrapper in events {
+        match wrapper {
+            EventWrapper::StaticEvent(event) => {
+                if !processing_redraws && event.is_redraw() {
+                    log::info!("processing `RedrawRequested` during the main event loop");
+                } else if processing_redraws && !event.is_redraw() {
+                    log::warn!(
+                        "processing non `RedrawRequested` event after the main event loop: {:#?}",
+                        event
+                    );
+                }
+                event_handler.handle_nonuser_event(event, &mut control_flow)
+            }
+            EventWrapper::EventProxy(proxy) => {
+                handle_event_proxy(&mut event_handler, control_flow, proxy)
+            }
         }
-        event_handler.handle_nonuser_event(event, &mut control_flow)
     }
 
     loop {
@@ -688,16 +702,23 @@ pub unsafe fn handle_nonuser_events<I: IntoIterator<Item = Event<Never>>>(events
         }
         drop(this);
 
-        for event in queued_events {
-            if !processing_redraws && event.is_redraw() {
-                log::info!("processing `RedrawRequested` during the main event loop");
-            } else if processing_redraws && !event.is_redraw() {
-                log::warn!(
-                    "processing non-`RedrawRequested` event after the main event loop: {:#?}",
-                    event
-                );
+        for wrapper in queued_events {
+            match wrapper {
+                EventWrapper::StaticEvent(event) => {
+                    if !processing_redraws && event.is_redraw() {
+                        log::info!("processing `RedrawRequested` during the main event loop");
+                    } else if processing_redraws && !event.is_redraw() {
+                        log::warn!(
+                            "processing non-`RedrawRequested` event after the main event loop: {:#?}",
+                            event
+                        );
+                    }
+                    event_handler.handle_nonuser_event(event, &mut control_flow)
+                }
+                EventWrapper::EventProxy(proxy) => {
+                    handle_event_proxy(&mut event_handler, control_flow, proxy)
+                }
             }
-            event_handler.handle_nonuser_event(event, &mut control_flow)
         }
     }
 }
@@ -751,8 +772,15 @@ unsafe fn handle_user_events() {
         }
         drop(this);
 
-        for event in queued_events {
-            event_handler.handle_nonuser_event(event, &mut control_flow)
+        for wrapper in queued_events {
+            match wrapper {
+                EventWrapper::StaticEvent(event) => {
+                    event_handler.handle_nonuser_event(event, &mut control_flow)
+                }
+                EventWrapper::EventProxy(proxy) => {
+                    handle_event_proxy(&mut event_handler, control_flow, proxy)
+                }
+            }
         }
         event_handler.handle_user_events(&mut control_flow);
     }
@@ -772,17 +800,19 @@ pub unsafe fn handle_main_events_cleared() {
 
     // User events are always sent out at the end of the "MainEventLoop"
     handle_user_events();
-    handle_nonuser_event(Event::MainEventsCleared);
+    handle_nonuser_event(EventWrapper::StaticEvent(Event::MainEventsCleared));
 
     let mut this = AppState::get_mut();
-    let mut redraw_events: Vec<Event<Never>> = this
+    let mut redraw_events: Vec<EventWrapper> = this
         .main_events_cleared_transition()
         .into_iter()
-        .map(|window| Event::RedrawRequested(RootWindowId(window.into())))
+        .map(|window| {
+            EventWrapper::StaticEvent(Event::RedrawRequested(RootWindowId(window.into())))
+        })
         .collect();
 
     if !redraw_events.is_empty() {
-        redraw_events.push(Event::RedrawEventsCleared);
+        redraw_events.push(EventWrapper::StaticEvent(Event::RedrawEventsCleared));
     }
     drop(this);
 
@@ -804,6 +834,66 @@ pub unsafe fn terminated() {
     event_handler.handle_nonuser_event(Event::LoopDestroyed, &mut control_flow)
 }
 
+fn handle_event_proxy(
+    event_handler: &mut Box<dyn EventHandler>,
+    control_flow: ControlFlow,
+    proxy: EventProxy,
+) {
+    match proxy {
+        EventProxy::DpiChangedProxy {
+            suggested_size,
+            scale_factor,
+            window_id,
+        } => handle_hidpi_proxy(
+            event_handler,
+            control_flow,
+            suggested_size,
+            scale_factor,
+            window_id,
+        ),
+    }
+}
+
+fn handle_hidpi_proxy(
+    event_handler: &mut Box<dyn EventHandler>,
+    mut control_flow: ControlFlow,
+    suggested_size: LogicalSize<f64>,
+    scale_factor: f64,
+    window_id: id,
+) {
+    let mut size = suggested_size.to_physical(scale_factor);
+    let new_inner_size = &mut size;
+    let event = Event::WindowEvent {
+        window_id: RootWindowId(window_id.into()),
+        event: WindowEvent::ScaleFactorChanged {
+            scale_factor,
+            new_inner_size,
+        },
+    };
+    event_handler.handle_nonuser_event(event, &mut control_flow);
+    let (view, screen_frame) = get_view_and_screen_frame(window_id);
+    let physical_size = *new_inner_size;
+    let logical_size = physical_size.to_logical(scale_factor);
+    let size = CGSize::new(logical_size);
+    let new_frame: CGRect = CGRect::new(screen_frame.origin, size);
+    unsafe {
+        let () = msg_send![view, setFrame: new_frame];
+    }
+}
+
+fn get_view_and_screen_frame(window_id: id) -> (id, CGRect) {
+    unsafe {
+        let view_controller: id = msg_send![window_id, rootViewController];
+        let view: id = msg_send![view_controller, view];
+        let bounds: CGRect = msg_send![window_id, bounds];
+        let screen: id = msg_send![window_id, screen];
+        let screen_space: id = msg_send![screen, coordinateSpace];
+        let screen_frame: CGRect =
+            msg_send![window_id, convertRect:bounds toCoordinateSpace:screen_space];
+        (view, screen_frame)
+    }
+}
+
 struct EventLoopWaker {
     timer: CFRunLoopTimerRef,
 }

src/platform_impl/ios/event_loop.rs

@@ -8,6 +8,7 @@ use std::{
 };
 
 use crate::{
+    dpi::LogicalSize,
     event::Event,
     event_loop::{
         ControlFlow, EventLoopClosed, EventLoopWindowTarget as RootEventLoopWindowTarget,
@@ -28,6 +29,21 @@ use crate::platform_impl::platform::{
     monitor, view, MonitorHandle,
 };
 
+#[derive(Debug)]
+pub enum EventWrapper {
+    StaticEvent(Event<'static, Never>),
+    EventProxy(EventProxy),
+}
+
+#[derive(Debug, PartialEq)]
+pub enum EventProxy {
+    DpiChangedProxy {
+        window_id: id,
+        suggested_size: LogicalSize<f64>,
+        scale_factor: f64,
+    },
+}
+
 pub struct EventLoopWindowTarget<T: 'static> {
     receiver: Receiver<T>,
     sender_to_clone: Sender<T>,
@@ -69,7 +85,7 @@ impl<T: 'static> EventLoop<T> {
 
     pub fn run<F>(self, event_handler: F) -> !
     where
-        F: 'static + FnMut(Event<T>, &RootEventLoopWindowTarget<T>, &mut ControlFlow),
+        F: 'static + FnMut(Event<'_, T>, &RootEventLoopWindowTarget<T>, &mut ControlFlow),
     {
         unsafe {
             let application: *mut c_void = msg_send![class!(UIApplication), sharedApplication];
@@ -199,10 +215,10 @@ fn setup_control_flow_observers() {
 
         // Core Animation registers its `CFRunLoopObserver` that performs drawing operations in
         // `CA::Transaction::ensure_implicit` with a priority of `0x1e8480`. We set the main_end
-        // priority to be 0, in order to send EventsCleared before RedrawRequested. This value was
+        // priority to be 0, in order to send MainEventsCleared before RedrawRequested. This value was
         // chosen conservatively to guard against apple using different priorities for their redraw
         // observers in different OS's or on different devices. If it so happens that it's too
-        // conservative, the main symptom would be non-redraw events coming in after `EventsCleared`.
+        // conservative, the main symptom would be non-redraw events coming in after `MainEventsCleared`.
         //
         // The value of `0x1e8480` was determined by inspecting stack traces and the associated
         // registers for every `CFRunLoopAddObserver` call on an iPad Air 2 running iOS 11.4.
@@ -277,7 +293,7 @@ fn setup_control_flow_observers() {
 pub enum Never {}
 
 pub trait EventHandler: Debug {
-    fn handle_nonuser_event(&mut self, event: Event<Never>, control_flow: &mut ControlFlow);
+    fn handle_nonuser_event(&mut self, event: Event<'_, Never>, control_flow: &mut ControlFlow);
     fn handle_user_events(&mut self, control_flow: &mut ControlFlow);
 }
 
@@ -296,10 +312,10 @@ impl<F, T: 'static> Debug for EventLoopHandler<F, T> {
 
 impl<F, T> EventHandler for EventLoopHandler<F, T>
 where
-    F: 'static + FnMut(Event<T>, &RootEventLoopWindowTarget<T>, &mut ControlFlow),
+    F: 'static + FnMut(Event<'_, T>, &RootEventLoopWindowTarget<T>, &mut ControlFlow),
     T: 'static,
 {
-    fn handle_nonuser_event(&mut self, event: Event<Never>, control_flow: &mut ControlFlow) {
+    fn handle_nonuser_event(&mut self, event: Event<'_, Never>, control_flow: &mut ControlFlow) {
         (self.f)(
             event.map_nonuser_event().unwrap(),
             &self.event_loop,

src/platform_impl/ios/ffi.rs

@@ -4,7 +4,10 @@ use std::{convert::TryInto, ffi::CString, ops::BitOr, os::raw::*};
 
 use objc::{runtime::Object, Encode, Encoding};
 
-use crate::platform::ios::{Idiom, ScreenEdge, ValidOrientations};
+use crate::{
+    dpi::LogicalSize,
+    platform::ios::{Idiom, ScreenEdge, ValidOrientations},
+};
 
 pub type id = *mut Object;
 pub const nil: id = 0 as id;
@@ -39,6 +42,15 @@ pub struct CGSize {
     pub height: CGFloat,
 }
 
+impl CGSize {
+    pub fn new(size: LogicalSize<f64>) -> CGSize {
+        CGSize {
+            width: size.width as _,
+            height: size.height as _,
+        }
+    }
+}
+
 #[repr(C)]
 #[derive(Debug, Clone)]
 pub struct CGRect {
@@ -46,6 +58,12 @@ pub struct CGRect {
     pub size: CGSize,
 }
 
+impl CGRect {
+    pub fn new(origin: CGPoint, size: CGSize) -> CGRect {
+        CGRect { origin, size }
+    }
+}
+
 unsafe impl Encode for CGRect {
     fn encode() -> Encoding {
         unsafe {

src/platform_impl/ios/mod.rs

@@ -83,6 +83,8 @@ pub use self::{
     window::{PlatformSpecificWindowBuilderAttributes, Window, WindowId},
 };
 
+pub(crate) use crate::icon::NoIcon as PlatformIcon;
+
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct DeviceId {
     uiscreen: ffi::id,

src/platform_impl/ios/monitor.rs

@@ -88,7 +88,7 @@ impl VideoMode {
         }
     }
 
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         self.size.into()
     }
 
@@ -171,16 +171,16 @@ impl fmt::Debug for MonitorHandle {
         #[derive(Debug)]
         struct MonitorHandle {
             name: Option<String>,
-            size: PhysicalSize,
-            position: PhysicalPosition,
-            hidpi_factor: f64,
+            size: PhysicalSize<u32>,
+            position: PhysicalPosition<i32>,
+            scale_factor: f64,
         }
 
         let monitor_id_proxy = MonitorHandle {
             name: self.name(),
             size: self.size(),
             position: self.position(),
-            hidpi_factor: self.hidpi_factor(),
+            scale_factor: self.scale_factor(),
         };
 
         monitor_id_proxy.fmt(f)
@@ -216,21 +216,21 @@ impl Inner {
         }
     }
 
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         unsafe {
             let bounds: CGRect = msg_send![self.ui_screen(), nativeBounds];
-            (bounds.size.width as f64, bounds.size.height as f64).into()
+            PhysicalSize::new(bounds.size.width as u32, bounds.size.height as u32)
         }
     }
 
-    pub fn position(&self) -> PhysicalPosition {
+    pub fn position(&self) -> PhysicalPosition<i32> {
         unsafe {
             let bounds: CGRect = msg_send![self.ui_screen(), nativeBounds];
             (bounds.origin.x as f64, bounds.origin.y as f64).into()
         }
     }
 
-    pub fn hidpi_factor(&self) -> f64 {
+    pub fn scale_factor(&self) -> f64 {
         unsafe {
             let scale: CGFloat = msg_send![self.ui_screen(), nativeScale];
             scale as f64

src/platform_impl/ios/view.rs

@@ -10,7 +10,7 @@ use crate::{
     platform::ios::MonitorHandleExtIOS,
     platform_impl::platform::{
         app_state::{self, OSCapabilities},
-        event_loop,
+        event_loop::{self, EventProxy, EventWrapper},
         ffi::{
             id, nil, CGFloat, CGPoint, CGRect, UIForceTouchCapability, UIInterfaceOrientationMask,
             UIRectEdge, UITouchPhase, UITouchType,
@@ -103,8 +103,12 @@ unsafe fn get_view_class(root_view_class: &'static Class) -> &'static Class {
                 let window: id = msg_send![object, window];
                 assert!(!window.is_null());
                 app_state::handle_nonuser_events(
-                    std::iter::once(Event::RedrawRequested(RootWindowId(window.into())))
-                        .chain(std::iter::once(Event::RedrawEventsCleared)),
+                    std::iter::once(EventWrapper::StaticEvent(Event::RedrawRequested(
+                        RootWindowId(window.into()),
+                    )))
+                    .chain(std::iter::once(EventWrapper::StaticEvent(
+                        Event::RedrawEventsCleared,
+                    ))),
                 );
                 let superclass: &'static Class = msg_send![object, superclass];
                 let () = msg_send![super(object, superclass), drawRect: rect];
@@ -123,27 +127,29 @@ unsafe fn get_view_class(root_view_class: &'static Class) -> &'static Class {
                 let screen_space: id = msg_send![screen, coordinateSpace];
                 let screen_frame: CGRect =
                     msg_send![object, convertRect:bounds toCoordinateSpace:screen_space];
+                let scale_factor: CGFloat = msg_send![screen, scale];
                 let size = crate::dpi::LogicalSize {
-                    width: screen_frame.size.width as _,
-                    height: screen_frame.size.height as _,
-                };
-                app_state::handle_nonuser_event(Event::WindowEvent {
+                    width: screen_frame.size.width as f64,
+                    height: screen_frame.size.height as f64,
+                }
+                .to_physical(scale_factor.into());
+                app_state::handle_nonuser_event(EventWrapper::StaticEvent(Event::WindowEvent {
                     window_id: RootWindowId(window.into()),
                     event: WindowEvent::Resized(size),
-                });
+                }));
             }
         }
 
         extern "C" fn set_content_scale_factor(
             object: &mut Object,
             _: Sel,
-            untrusted_hidpi_factor: CGFloat,
+            untrusted_scale_factor: CGFloat,
         ) {
             unsafe {
                 let superclass: &'static Class = msg_send![object, superclass];
                 let () = msg_send![
                     super(object, superclass),
-                    setContentScaleFactor: untrusted_hidpi_factor
+                    setContentScaleFactor: untrusted_scale_factor
                 ];
 
                 let window: id = msg_send![object, window];
@@ -156,14 +162,15 @@ unsafe fn get_view_class(root_view_class: &'static Class) -> &'static Class {
                 // `setContentScaleFactor` may be called with a value of 0, which means "reset the
                 // content scale factor to a device-specific default value", so we can't use the
                 // parameter here. We can query the actual factor using the getter
-                let hidpi_factor: CGFloat = msg_send![object, contentScaleFactor];
+                let scale_factor: CGFloat = msg_send![object, contentScaleFactor];
                 assert!(
-                    !hidpi_factor.is_nan()
-                        && hidpi_factor.is_finite()
-                        && hidpi_factor.is_sign_positive()
-                        && hidpi_factor > 0.0,
-                    "invalid hidpi_factor set on UIView",
+                    !scale_factor.is_nan()
+                        && scale_factor.is_finite()
+                        && scale_factor.is_sign_positive()
+                        && scale_factor > 0.0,
+                    "invalid scale_factor set on UIView",
                 );
+                let scale_factor: f64 = scale_factor.into();
                 let bounds: CGRect = msg_send![object, bounds];
                 let screen: id = msg_send![window, screen];
                 let screen_space: id = msg_send![screen, coordinateSpace];
@@ -174,14 +181,17 @@ unsafe fn get_view_class(root_view_class: &'static Class) -> &'static Class {
                     height: screen_frame.size.height as _,
                 };
                 app_state::handle_nonuser_events(
-                    std::iter::once(Event::WindowEvent {
-                        window_id: RootWindowId(window.into()),
-                        event: WindowEvent::HiDpiFactorChanged(hidpi_factor as _),
-                    })
-                    .chain(std::iter::once(Event::WindowEvent {
-                        window_id: RootWindowId(window.into()),
-                        event: WindowEvent::Resized(size),
-                    })),
+                    std::iter::once(EventWrapper::EventProxy(EventProxy::DpiChangedProxy {
+                        window_id: window,
+                        scale_factor,
+                        suggested_size: size,
+                    }))
+                    .chain(std::iter::once(EventWrapper::StaticEvent(
+                        Event::WindowEvent {
+                            window_id: RootWindowId(window.into()),
+                            event: WindowEvent::Resized(size.to_physical(scale_factor)),
+                        },
+                    ))),
                 );
             }
         }
@@ -238,7 +248,7 @@ unsafe fn get_view_class(root_view_class: &'static Class) -> &'static Class {
                         _ => panic!("unexpected touch phase: {:?}", phase as i32),
                     };
 
-                    touch_events.push(Event::WindowEvent {
+                    touch_events.push(EventWrapper::StaticEvent(Event::WindowEvent {
                         window_id: RootWindowId(window.into()),
                         event: WindowEvent::Touch(Touch {
                             device_id: RootDeviceId(DeviceId { uiscreen }),
@@ -247,7 +257,7 @@ unsafe fn get_view_class(root_view_class: &'static Class) -> &'static Class {
                             force,
                             phase,
                         }),
-                    });
+                    }));
                 }
                 app_state::handle_nonuser_events(touch_events);
             }
@@ -367,20 +377,20 @@ unsafe fn get_window_class() -> &'static Class {
 
         extern "C" fn become_key_window(object: &Object, _: Sel) {
             unsafe {
-                app_state::handle_nonuser_event(Event::WindowEvent {
+                app_state::handle_nonuser_event(EventWrapper::StaticEvent(Event::WindowEvent {
                     window_id: RootWindowId(object.into()),
                     event: WindowEvent::Focused(true),
-                });
+                }));
                 let () = msg_send![super(object, class!(UIWindow)), becomeKeyWindow];
             }
         }
 
         extern "C" fn resign_key_window(object: &Object, _: Sel) {
             unsafe {
-                app_state::handle_nonuser_event(Event::WindowEvent {
+                app_state::handle_nonuser_event(EventWrapper::StaticEvent(Event::WindowEvent {
                     window_id: RootWindowId(object.into()),
                     event: WindowEvent::Focused(false),
-                });
+                }));
                 let () = msg_send![super(object, class!(UIWindow)), resignKeyWindow];
             }
         }
@@ -414,8 +424,8 @@ pub unsafe fn create_view(
     let view: id = msg_send![view, initWithFrame: frame];
     assert!(!view.is_null(), "Failed to initialize `UIView` instance");
     let () = msg_send![view, setMultipleTouchEnabled: YES];
-    if let Some(hidpi_factor) = platform_attributes.hidpi_factor {
-        let () = msg_send![view, setContentScaleFactor: hidpi_factor as CGFloat];
+    if let Some(scale_factor) = platform_attributes.scale_factor {
+        let () = msg_send![view, setContentScaleFactor: scale_factor as CGFloat];
     }
 
     view
@@ -518,11 +528,11 @@ pub fn create_delegate_class() {
     }
 
     extern "C" fn did_become_active(_: &Object, _: Sel, _: id) {
-        unsafe { app_state::handle_nonuser_event(Event::Resumed) }
+        unsafe { app_state::handle_nonuser_event(EventWrapper::StaticEvent(Event::Resumed)) }
     }
 
     extern "C" fn will_resign_active(_: &Object, _: Sel, _: id) {
-        unsafe { app_state::handle_nonuser_event(Event::Suspended) }
+        unsafe { app_state::handle_nonuser_event(EventWrapper::StaticEvent(Event::Suspended)) }
     }
 
     extern "C" fn will_enter_foreground(_: &Object, _: Sel, _: id) {}
@@ -541,10 +551,10 @@ pub fn create_delegate_class() {
                 }
                 let is_winit_window: BOOL = msg_send![window, isKindOfClass: class!(WinitUIWindow)];
                 if is_winit_window == YES {
-                    events.push(Event::WindowEvent {
+                    events.push(EventWrapper::StaticEvent(Event::WindowEvent {
                         window_id: RootWindowId(window.into()),
                         event: WindowEvent::Destroyed,
-                    });
+                    }));
                 }
             }
             app_state::handle_nonuser_events(events);

src/platform_impl/ios/window.rs

@@ -7,14 +7,15 @@ use std::{
 use objc::runtime::{Class, Object, BOOL, NO, YES};
 
 use crate::{
-    dpi::{self, LogicalPosition, LogicalSize},
+    dpi::{self, LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize, Position, Size},
     error::{ExternalError, NotSupportedError, OsError as RootOsError},
     event::{Event, WindowEvent},
     icon::Icon,
     monitor::MonitorHandle as RootMonitorHandle,
     platform::ios::{MonitorHandleExtIOS, ScreenEdge, ValidOrientations},
     platform_impl::platform::{
-        app_state, event_loop,
+        app_state,
+        event_loop::{self, EventProxy, EventWrapper},
         ffi::{
             id, CGFloat, CGPoint, CGRect, CGSize, UIEdgeInsets, UIInterfaceOrientationMask,
             UIRectEdge, UIScreenOverscanCompensation,
@@ -75,28 +76,34 @@ impl Inner {
         }
     }
 
-    pub fn inner_position(&self) -> Result<LogicalPosition, NotSupportedError> {
+    pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         unsafe {
             let safe_area = self.safe_area_screen_space();
-            Ok(LogicalPosition {
-                x: safe_area.origin.x as _,
-                y: safe_area.origin.y as _,
-            })
+            let position = LogicalPosition {
+                x: safe_area.origin.x as f64,
+                y: safe_area.origin.y as f64,
+            };
+            let scale_factor = self.scale_factor();
+            Ok(position.to_physical(scale_factor))
         }
     }
 
-    pub fn outer_position(&self) -> Result<LogicalPosition, NotSupportedError> {
+    pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         unsafe {
             let screen_frame = self.screen_frame();
-            Ok(LogicalPosition {
-                x: screen_frame.origin.x as _,
-                y: screen_frame.origin.y as _,
-            })
+            let position = LogicalPosition {
+                x: screen_frame.origin.x as f64,
+                y: screen_frame.origin.y as f64,
+            };
+            let scale_factor = self.scale_factor();
+            Ok(position.to_physical(scale_factor))
         }
     }
 
-    pub fn set_outer_position(&self, position: LogicalPosition) {
+    pub fn set_outer_position(&self, physical_position: Position) {
         unsafe {
+            let scale_factor = self.scale_factor();
+            let position = physical_position.to_logical::<f64>(scale_factor);
             let screen_frame = self.screen_frame();
             let new_screen_frame = CGRect {
                 origin: CGPoint {
@@ -110,35 +117,39 @@ impl Inner {
         }
     }
 
-    pub fn inner_size(&self) -> LogicalSize {
+    pub fn inner_size(&self) -> PhysicalSize<u32> {
         unsafe {
+            let scale_factor = self.scale_factor();
             let safe_area = self.safe_area_screen_space();
-            LogicalSize {
-                width: safe_area.size.width as _,
-                height: safe_area.size.height as _,
-            }
+            let size = LogicalSize {
+                width: safe_area.size.width as f64,
+                height: safe_area.size.height as f64,
+            };
+            size.to_physical(scale_factor)
         }
     }
 
-    pub fn outer_size(&self) -> LogicalSize {
+    pub fn outer_size(&self) -> PhysicalSize<u32> {
         unsafe {
+            let scale_factor = self.scale_factor();
             let screen_frame = self.screen_frame();
-            LogicalSize {
-                width: screen_frame.size.width as _,
-                height: screen_frame.size.height as _,
-            }
+            let size = LogicalSize {
+                width: screen_frame.size.width as f64,
+                height: screen_frame.size.height as f64,
+            };
+            size.to_physical(scale_factor)
         }
     }
 
-    pub fn set_inner_size(&self, _size: LogicalSize) {
+    pub fn set_inner_size(&self, _size: Size) {
         unimplemented!("not clear what `Window::set_inner_size` means on iOS");
     }
 
-    pub fn set_min_inner_size(&self, _dimensions: Option<LogicalSize>) {
+    pub fn set_min_inner_size(&self, _dimensions: Option<Size>) {
         warn!("`Window::set_min_inner_size` is ignored on iOS")
     }
 
-    pub fn set_max_inner_size(&self, _dimensions: Option<LogicalSize>) {
+    pub fn set_max_inner_size(&self, _dimensions: Option<Size>) {
         warn!("`Window::set_max_inner_size` is ignored on iOS")
     }
 
@@ -146,7 +157,7 @@ impl Inner {
         warn!("`Window::set_resizable` is ignored on iOS")
     }
 
-    pub fn hidpi_factor(&self) -> f64 {
+    pub fn scale_factor(&self) -> f64 {
         unsafe {
             let hidpi: CGFloat = msg_send![self.view, contentScaleFactor];
             hidpi as _
@@ -157,7 +168,7 @@ impl Inner {
         debug!("`Window::set_cursor_icon` ignored on iOS")
     }
 
-    pub fn set_cursor_position(&self, _position: LogicalPosition) -> Result<(), ExternalError> {
+    pub fn set_cursor_position(&self, _position: Position) -> Result<(), ExternalError> {
         Err(ExternalError::NotSupported(NotSupportedError::new()))
     }
 
@@ -243,7 +254,7 @@ impl Inner {
         warn!("`Window::set_window_icon` is ignored on iOS")
     }
 
-    pub fn set_ime_position(&self, _position: LogicalPosition) {
+    pub fn set_ime_position(&self, _position: Position) {
         warn!("`Window::set_ime_position` is ignored on iOS")
     }
 
@@ -343,13 +354,17 @@ impl Window {
             let screen_bounds: CGRect = msg_send![screen, bounds];
 
             let frame = match window_attributes.inner_size {
-                Some(dim) => CGRect {
-                    origin: screen_bounds.origin,
-                    size: CGSize {
-                        width: dim.width as _,
-                        height: dim.height as _,
-                    },
-                },
+                Some(dim) => {
+                    let scale_factor = msg_send![screen, scale];
+                    let size = dim.to_logical::<f64>(scale_factor);
+                    CGRect {
+                        origin: screen_bounds.origin,
+                        size: CGSize {
+                            width: size.width as _,
+                            height: size.height as _,
+                        },
+                    }
+                }
                 None => screen_bounds,
             };
 
@@ -383,10 +398,11 @@ impl Window {
             };
             app_state::set_key_window(window);
 
-            // Like the Windows and macOS backends, we send a `HiDpiFactorChanged` and `Resized`
+            // Like the Windows and macOS backends, we send a `ScaleFactorChanged` and `Resized`
             // event on window creation if the DPI factor != 1.0
-            let hidpi_factor: CGFloat = msg_send![view, contentScaleFactor];
-            if hidpi_factor != 1.0 {
+            let scale_factor: CGFloat = msg_send![view, contentScaleFactor];
+            let scale_factor: f64 = scale_factor.into();
+            if scale_factor != 1.0 {
                 let bounds: CGRect = msg_send![view, bounds];
                 let screen: id = msg_send![window, screen];
                 let screen_space: id = msg_send![screen, coordinateSpace];
@@ -397,14 +413,17 @@ impl Window {
                     height: screen_frame.size.height as _,
                 };
                 app_state::handle_nonuser_events(
-                    std::iter::once(Event::WindowEvent {
-                        window_id: RootWindowId(window.into()),
-                        event: WindowEvent::HiDpiFactorChanged(hidpi_factor as _),
-                    })
-                    .chain(std::iter::once(Event::WindowEvent {
-                        window_id: RootWindowId(window.into()),
-                        event: WindowEvent::Resized(size),
-                    })),
+                    std::iter::once(EventWrapper::EventProxy(EventProxy::DpiChangedProxy {
+                        window_id: window,
+                        scale_factor,
+                        suggested_size: size,
+                    }))
+                    .chain(std::iter::once(EventWrapper::StaticEvent(
+                        Event::WindowEvent {
+                            window_id: RootWindowId(window.into()),
+                            event: WindowEvent::Resized(size.to_physical(scale_factor)),
+                        },
+                    ))),
                 );
             }
 
@@ -425,14 +444,14 @@ impl Inner {
         self.view
     }
 
-    pub fn set_hidpi_factor(&self, hidpi_factor: f64) {
+    pub fn set_scale_factor(&self, scale_factor: f64) {
         unsafe {
             assert!(
-                dpi::validate_hidpi_factor(hidpi_factor),
-                "`WindowExtIOS::set_hidpi_factor` received an invalid hidpi factor"
+                dpi::validate_scale_factor(scale_factor),
+                "`WindowExtIOS::set_scale_factor` received an invalid hidpi factor"
             );
-            let hidpi_factor = hidpi_factor as CGFloat;
-            let () = msg_send![self.view, setContentScaleFactor: hidpi_factor];
+            let scale_factor = scale_factor as CGFloat;
+            let () = msg_send![self.view, setContentScaleFactor: scale_factor];
         }
     }
 
@@ -598,7 +617,7 @@ impl From<id> for WindowId {
 #[derive(Clone)]
 pub struct PlatformSpecificWindowBuilderAttributes {
     pub root_view_class: &'static Class,
-    pub hidpi_factor: Option<f64>,
+    pub scale_factor: Option<f64>,
     pub valid_orientations: ValidOrientations,
     pub prefers_home_indicator_hidden: bool,
     pub prefers_status_bar_hidden: bool,
@@ -609,7 +628,7 @@ impl Default for PlatformSpecificWindowBuilderAttributes {
     fn default() -> PlatformSpecificWindowBuilderAttributes {
         PlatformSpecificWindowBuilderAttributes {
             root_view_class: class!(UIView),
-            hidpi_factor: None,
+            scale_factor: None,
             valid_orientations: Default::default(),
             prefers_home_indicator_hidden: false,
             prefers_status_bar_hidden: false,

src/platform_impl/linux/mod.rs

@@ -7,11 +7,9 @@ use raw_window_handle::RawWindowHandle;
 use smithay_client_toolkit::reexports::client::ConnectError;
 
 pub use self::x11::XNotSupported;
-use self::x11::{
-    ffi::XVisualInfo, get_xtarget, util::WindowType as XWindowType, XConnection, XError,
-};
+use self::x11::{ffi::XVisualInfo, util::WindowType as XWindowType, XConnection, XError};
 use crate::{
-    dpi::{LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize},
+    dpi::{PhysicalPosition, PhysicalSize, Position, Size},
     error::{ExternalError, NotSupportedError, OsError as RootOsError},
     event::Event,
     event_loop::{ControlFlow, EventLoopClosed, EventLoopWindowTarget as RootELW},
@@ -20,6 +18,8 @@ use crate::{
     window::{CursorIcon, Fullscreen, WindowAttributes},
 };
 
+pub(crate) use crate::icon::RgbaIcon as PlatformIcon;
+
 pub mod wayland;
 pub mod x11;
 
@@ -36,8 +36,8 @@ const BACKEND_PREFERENCE_ENV_VAR: &str = "WINIT_UNIX_BACKEND";
 pub struct PlatformSpecificWindowBuilderAttributes {
     pub visual_infos: Option<XVisualInfo>,
     pub screen_id: Option<i32>,
-    pub resize_increments: Option<(u32, u32)>,
-    pub base_size: Option<(u32, u32)>,
+    pub resize_increments: Option<Size>,
+    pub base_size: Option<Size>,
     pub class: Option<(String, String)>,
     pub override_redirect: bool,
     pub x11_window_types: Vec<XWindowType>,
@@ -134,7 +134,7 @@ impl MonitorHandle {
     }
 
     #[inline]
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         match self {
             &MonitorHandle::X(ref m) => m.size(),
             &MonitorHandle::Wayland(ref m) => m.size(),
@@ -142,7 +142,7 @@ impl MonitorHandle {
     }
 
     #[inline]
-    pub fn position(&self) -> PhysicalPosition {
+    pub fn position(&self) -> PhysicalPosition<i32> {
         match self {
             &MonitorHandle::X(ref m) => m.position(),
             &MonitorHandle::Wayland(ref m) => m.position(),
@@ -150,10 +150,10 @@ impl MonitorHandle {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f64 {
+    pub fn scale_factor(&self) -> f64 {
         match self {
-            &MonitorHandle::X(ref m) => m.hidpi_factor(),
-            &MonitorHandle::Wayland(ref m) => m.hidpi_factor() as f64,
+            &MonitorHandle::X(ref m) => m.scale_factor(),
+            &MonitorHandle::Wayland(ref m) => m.scale_factor() as f64,
         }
     }
 
@@ -174,7 +174,7 @@ pub enum VideoMode {
 
 impl VideoMode {
     #[inline]
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         match self {
             &VideoMode::X(ref m) => m.size(),
             &VideoMode::Wayland(ref m) => m.size(),
@@ -248,7 +248,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn outer_position(&self) -> Result<LogicalPosition, NotSupportedError> {
+    pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         match self {
             &Window::X(ref w) => w.outer_position(),
             &Window::Wayland(ref w) => w.outer_position(),
@@ -256,7 +256,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn inner_position(&self) -> Result<LogicalPosition, NotSupportedError> {
+    pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         match self {
             &Window::X(ref m) => m.inner_position(),
             &Window::Wayland(ref m) => m.inner_position(),
@@ -264,7 +264,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_outer_position(&self, position: LogicalPosition) {
+    pub fn set_outer_position(&self, position: Position) {
         match self {
             &Window::X(ref w) => w.set_outer_position(position),
             &Window::Wayland(ref w) => w.set_outer_position(position),
@@ -272,7 +272,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn inner_size(&self) -> LogicalSize {
+    pub fn inner_size(&self) -> PhysicalSize<u32> {
         match self {
             &Window::X(ref w) => w.inner_size(),
             &Window::Wayland(ref w) => w.inner_size(),
@@ -280,7 +280,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn outer_size(&self) -> LogicalSize {
+    pub fn outer_size(&self) -> PhysicalSize<u32> {
         match self {
             &Window::X(ref w) => w.outer_size(),
             &Window::Wayland(ref w) => w.outer_size(),
@@ -288,7 +288,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_inner_size(&self, size: LogicalSize) {
+    pub fn set_inner_size(&self, size: Size) {
         match self {
             &Window::X(ref w) => w.set_inner_size(size),
             &Window::Wayland(ref w) => w.set_inner_size(size),
@@ -296,7 +296,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_min_inner_size(&self, dimensions: Option<LogicalSize>) {
+    pub fn set_min_inner_size(&self, dimensions: Option<Size>) {
         match self {
             &Window::X(ref w) => w.set_min_inner_size(dimensions),
             &Window::Wayland(ref w) => w.set_min_inner_size(dimensions),
@@ -304,7 +304,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_max_inner_size(&self, dimensions: Option<LogicalSize>) {
+    pub fn set_max_inner_size(&self, dimensions: Option<Size>) {
         match self {
             &Window::X(ref w) => w.set_max_inner_size(dimensions),
             &Window::Wayland(ref w) => w.set_max_inner_size(dimensions),
@@ -344,15 +344,15 @@ impl Window {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f64 {
+    pub fn scale_factor(&self) -> f64 {
         match self {
-            &Window::X(ref w) => w.hidpi_factor(),
-            &Window::Wayland(ref w) => w.hidpi_factor() as f64,
+            &Window::X(ref w) => w.scale_factor(),
+            &Window::Wayland(ref w) => w.scale_factor() as f64,
         }
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, position: LogicalPosition) -> Result<(), ExternalError> {
+    pub fn set_cursor_position(&self, position: Position) -> Result<(), ExternalError> {
         match self {
             &Window::X(ref w) => w.set_cursor_position(position),
             &Window::Wayland(ref w) => w.set_cursor_position(position),
@@ -416,7 +416,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_position(&self, position: LogicalPosition) {
+    pub fn set_ime_position(&self, position: Position) {
         match self {
             &Window::X(ref w) => w.set_ime_position(position),
             &Window::Wayland(_) => (),
@@ -586,13 +586,12 @@ impl<T: 'static> EventLoop<T> {
     }
 
     pub fn new_x11_any_thread() -> Result<EventLoop<T>, XNotSupported> {
-        X11_BACKEND
-            .lock()
-            .as_ref()
-            .map(Arc::clone)
-            .map(x11::EventLoop::new)
-            .map(EventLoop::X)
-            .map_err(|err| err.clone())
+        let xconn = match X11_BACKEND.lock().as_ref() {
+            Ok(xconn) => xconn.clone(),
+            Err(err) => return Err(err.clone()),
+        };
+
+        Ok(EventLoop::X(x11::EventLoop::new(xconn)))
     }
 
     #[inline]
@@ -603,7 +602,7 @@ impl<T: 'static> EventLoop<T> {
                 .into_iter()
                 .map(MonitorHandle::Wayland)
                 .collect(),
-            EventLoop::X(ref evlp) => get_xtarget(&evlp.target)
+            EventLoop::X(ref evlp) => evlp
                 .x_connection()
                 .available_monitors()
                 .into_iter()
@@ -616,9 +615,7 @@ impl<T: 'static> EventLoop<T> {
     pub fn primary_monitor(&self) -> MonitorHandle {
         match *self {
             EventLoop::Wayland(ref evlp) => MonitorHandle::Wayland(evlp.primary_monitor()),
-            EventLoop::X(ref evlp) => {
-                MonitorHandle::X(get_xtarget(&evlp.target).x_connection().primary_monitor())
-            }
+            EventLoop::X(ref evlp) => MonitorHandle::X(evlp.x_connection().primary_monitor()),
         }
     }
 
@@ -631,7 +628,7 @@ impl<T: 'static> EventLoop<T> {
 
     pub fn run_return<F>(&mut self, callback: F)
     where
-        F: FnMut(crate::event::Event<T>, &RootELW<T>, &mut ControlFlow),
+        F: FnMut(crate::event::Event<'_, T>, &RootELW<T>, &mut ControlFlow),
     {
         match *self {
             EventLoop::Wayland(ref mut evlp) => evlp.run_return(callback),
@@ -641,7 +638,7 @@ impl<T: 'static> EventLoop<T> {
 
     pub fn run<F>(self, callback: F) -> !
     where
-        F: 'static + FnMut(crate::event::Event<T>, &RootELW<T>, &mut ControlFlow),
+        F: 'static + FnMut(crate::event::Event<'_, T>, &RootELW<T>, &mut ControlFlow),
     {
         match self {
             EventLoop::Wayland(evlp) => evlp.run(callback),
@@ -682,12 +679,12 @@ impl<T> EventLoopWindowTarget<T> {
 }
 
 fn sticky_exit_callback<T, F>(
-    evt: Event<T>,
+    evt: Event<'_, T>,
     target: &RootELW<T>,
     control_flow: &mut ControlFlow,
     callback: &mut F,
 ) where
-    F: FnMut(Event<T>, &RootELW<T>, &mut ControlFlow),
+    F: FnMut(Event<'_, T>, &RootELW<T>, &mut ControlFlow),
 {
     // make ControlFlow::Exit sticky by providing a dummy
     // control flow reference if it is already Exit.

src/platform_impl/linux/wayland/event_loop.rs

@@ -2,11 +2,16 @@ use std::{
     cell::RefCell,
     collections::VecDeque,
     fmt,
+    io::ErrorKind,
     rc::Rc,
     sync::{Arc, Mutex},
-    time::Instant,
+    time::{Duration, Instant},
 };
 
+use mio::{Events, Poll, PollOpt, Ready, Token};
+
+use mio_extras::channel::{channel, Receiver, SendError, Sender};
+
 use smithay_client_toolkit::reexports::protocols::unstable::pointer_constraints::v1::client::{
     zwp_locked_pointer_v1::ZwpLockedPointerV1, zwp_pointer_constraints_v1::ZwpPointerConstraintsV1,
 };
@@ -21,18 +26,23 @@ use smithay_client_toolkit::reexports::client::protocol::{
 };
 
 use crate::{
-    dpi::{PhysicalPosition, PhysicalSize},
-    event::ModifiersState,
+    dpi::{LogicalSize, PhysicalPosition, PhysicalSize},
+    event::{
+        DeviceEvent, DeviceId as RootDeviceId, Event, ModifiersState, StartCause, WindowEvent,
+    },
     event_loop::{ControlFlow, EventLoopClosed, EventLoopWindowTarget as RootELW},
     monitor::{MonitorHandle as RootMonitorHandle, VideoMode as RootVideoMode},
     platform_impl::platform::{
-        sticky_exit_callback, MonitorHandle as PlatformMonitorHandle,
-        VideoMode as PlatformVideoMode,
+        sticky_exit_callback, DeviceId as PlatformDeviceId, MonitorHandle as PlatformMonitorHandle,
+        VideoMode as PlatformVideoMode, WindowId as PlatformWindowId,
     },
-    window::CursorIcon,
+    window::{CursorIcon, WindowId as RootWindowId},
 };
 
-use super::{window::WindowStore, DeviceId, WindowId};
+use super::{
+    window::{DecorationsAction, WindowStore},
+    DeviceId, WindowId,
+};
 
 use smithay_client_toolkit::{
     output::OutputMgr,
@@ -43,43 +53,37 @@ use smithay_client_toolkit::{
     Environment,
 };
 
-pub struct WindowEventsSink<T> {
-    buffer: VecDeque<crate::event::Event<T>>,
+const KBD_TOKEN: Token = Token(0);
+const USER_TOKEN: Token = Token(1);
+const EVQ_TOKEN: Token = Token(2);
+
+#[derive(Clone)]
+pub struct EventsSink {
+    sender: Sender<Event<'static, ()>>,
 }
 
-impl<T> WindowEventsSink<T> {
-    pub fn new() -> WindowEventsSink<T> {
-        WindowEventsSink {
-            buffer: VecDeque::new(),
-        }
+impl EventsSink {
+    pub fn new(sender: Sender<Event<'static, ()>>) -> EventsSink {
+        EventsSink { sender }
     }
 
-    pub fn send_event(&mut self, evt: crate::event::Event<T>) {
-        self.buffer.push_back(evt);
+    pub fn send_event(&self, event: Event<'static, ()>) {
+        self.sender.send(event).unwrap()
     }
 
-    pub fn send_window_event(&mut self, evt: crate::event::WindowEvent, wid: WindowId) {
-        self.buffer.push_back(crate::event::Event::WindowEvent {
-            event: evt,
-            window_id: crate::window::WindowId(crate::platform_impl::WindowId::Wayland(wid)),
+    pub fn send_device_event(&self, event: DeviceEvent, device_id: DeviceId) {
+        self.send_event(Event::DeviceEvent {
+            event,
+            device_id: RootDeviceId(PlatformDeviceId::Wayland(device_id)),
         });
     }
 
-    pub fn send_device_event(&mut self, evt: crate::event::DeviceEvent, dev_id: DeviceId) {
-        self.buffer.push_back(crate::event::Event::DeviceEvent {
-            event: evt,
-            device_id: crate::event::DeviceId(crate::platform_impl::DeviceId::Wayland(dev_id)),
+    pub fn send_window_event(&self, event: WindowEvent<'static>, window_id: WindowId) {
+        self.send_event(Event::WindowEvent {
+            event,
+            window_id: RootWindowId(PlatformWindowId::Wayland(window_id)),
         });
     }
-
-    fn empty_with<F>(&mut self, mut callback: F)
-    where
-        F: FnMut(crate::event::Event<T>),
-    {
-        for evt in self.buffer.drain(..) {
-            callback(evt)
-        }
-    }
 }
 
 pub struct CursorManager {
@@ -89,6 +93,7 @@ pub struct CursorManager {
     locked_pointers: Vec<ZwpLockedPointerV1>,
     cursor_visible: bool,
     current_cursor: CursorIcon,
+    scale_factor: u32,
 }
 
 impl CursorManager {
@@ -100,6 +105,7 @@ impl CursorManager {
             locked_pointers: Vec::new(),
             cursor_visible: true,
             current_cursor: CursorIcon::default(),
+            scale_factor: 1,
         }
     }
 
@@ -144,6 +150,11 @@ impl CursorManager {
         }
     }
 
+    pub fn update_scale_factor(&mut self, scale: u32) {
+        self.scale_factor = scale;
+        self.reload_cursor_style();
+    }
+
     fn set_cursor_icon_impl(&mut self, cursor: CursorIcon) {
         let cursor = match cursor {
             CursorIcon::Alias => "link",
@@ -192,7 +203,7 @@ impl CursorManager {
         for pointer in self.pointers.iter() {
             // Ignore erros, since we don't want to fail hard in case we can't find a proper cursor
             // in a given theme.
-            let _ = pointer.set_cursor(cursor, None);
+            let _ = pointer.set_cursor_with_scale(cursor, self.scale_factor, None);
         }
     }
 
@@ -230,21 +241,17 @@ impl CursorManager {
 }
 
 pub struct EventLoop<T: 'static> {
-    // The loop
-    inner_loop: ::calloop::EventLoop<()>,
+    // Poll instance
+    poll: Poll,
     // The wayland display
     pub display: Arc<Display>,
     // The output manager
     pub outputs: OutputMgr,
-    // Our sink, shared with some handlers, buffering the events
-    sink: Arc<Mutex<WindowEventsSink<T>>>,
-    pending_user_events: Rc<RefCell<VecDeque<T>>>,
     // The cursor manager
     cursor_manager: Arc<Mutex<CursorManager>>,
-    // Utility for grabbing the cursor and changing visibility
-    _user_source: ::calloop::Source<::calloop::channel::Channel<T>>,
-    user_sender: ::calloop::channel::Sender<T>,
-    _kbd_source: ::calloop::Source<::calloop::channel::Channel<crate::event::Event<()>>>,
+    kbd_channel: Receiver<Event<'static, ()>>,
+    user_channel: Receiver<T>,
+    user_sender: Sender<T>,
     window_target: RootELW<T>,
 }
 
@@ -252,12 +259,12 @@ pub struct EventLoop<T: 'static> {
 //
 // We should only try and wake up the `EventLoop` if it still exists, so we hold Weak ptrs.
 pub struct EventLoopProxy<T: 'static> {
-    user_sender: calloop::channel::Sender<T>,
+    user_sender: Sender<T>,
 }
 
 pub struct EventLoopWindowTarget<T> {
-    // The event queue
-    pub evq: RefCell<::calloop::Source<EventQueue>>,
+    // the event queue
+    pub evq: RefCell<EventQueue>,
     // The window store
     pub store: Arc<Mutex<WindowStore>>,
     // The cursor manager
@@ -284,7 +291,7 @@ impl<T: 'static> Clone for EventLoopProxy<T> {
 impl<T: 'static> EventLoopProxy<T> {
     pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed<T>> {
         self.user_sender.send(event).map_err(|e| {
-            EventLoopClosed(if let ::calloop::channel::SendError::Disconnected(x) = e {
+            EventLoopClosed(if let SendError::Disconnected(x) = e {
                 x
             } else {
                 unreachable!()
@@ -298,33 +305,26 @@ impl<T: 'static> EventLoop<T> {
         let (display, mut event_queue) = Display::connect_to_env()?;
 
         let display = Arc::new(display);
-        let sink = Arc::new(Mutex::new(WindowEventsSink::new()));
         let store = Arc::new(Mutex::new(WindowStore::new()));
         let seats = Arc::new(Mutex::new(Vec::new()));
 
-        let inner_loop = ::calloop::EventLoop::new().unwrap();
+        let poll = Poll::new().unwrap();
 
-        let (kbd_sender, kbd_channel) = ::calloop::channel::channel::<crate::event::Event<()>>();
-        let kbd_sink = sink.clone();
-        let kbd_source = inner_loop
-            .handle()
-            .insert_source(kbd_channel, move |evt, &mut ()| {
-                if let ::calloop::channel::Event::Msg(evt) = evt {
-                    let evt = evt.map_nonuser_event().ok().unwrap();
-                    kbd_sink.lock().unwrap().send_event(evt);
-                }
-            })
+        let (kbd_sender, kbd_channel) = channel();
+
+        let sink = EventsSink::new(kbd_sender);
+
+        poll.register(&kbd_channel, KBD_TOKEN, Ready::readable(), PollOpt::level())
             .unwrap();
 
         let pointer_constraints_proxy = Arc::new(Mutex::new(None));
 
         let mut seat_manager = SeatManager {
-            sink: sink.clone(),
-            relative_pointer_manager_proxy: Rc::new(RefCell::new(None)),
-            pointer_constraints_proxy: pointer_constraints_proxy.clone(),
+            sink,
             store: store.clone(),
             seats: seats.clone(),
-            kbd_sender,
+            relative_pointer_manager_proxy: Rc::new(RefCell::new(None)),
+            pointer_constraints_proxy: pointer_constraints_proxy.clone(),
             cursor_manager: Arc::new(Mutex::new(CursorManager::new(pointer_constraints_proxy))),
         };
 
@@ -404,39 +404,31 @@ impl<T: 'static> EventLoop<T> {
         )
         .unwrap();
 
-        let source = inner_loop
-            .handle()
-            .insert_source(event_queue, |(), &mut ()| {})
+        poll.register(&event_queue, EVQ_TOKEN, Ready::readable(), PollOpt::level())
             .unwrap();
 
-        let pending_user_events = Rc::new(RefCell::new(VecDeque::new()));
-        let pending_user_events2 = pending_user_events.clone();
+        let (user_sender, user_channel) = channel();
 
-        let (user_sender, user_channel) = ::calloop::channel::channel();
-
-        let user_source = inner_loop
-            .handle()
-            .insert_source(user_channel, move |evt, &mut ()| {
-                if let ::calloop::channel::Event::Msg(msg) = evt {
-                    pending_user_events2.borrow_mut().push_back(msg);
-                }
-            })
-            .unwrap();
+        poll.register(
+            &user_channel,
+            USER_TOKEN,
+            Ready::readable(),
+            PollOpt::level(),
+        )
+        .unwrap();
 
         let cursor_manager_clone = cursor_manager.clone();
         Ok(EventLoop {
-            inner_loop,
-            sink,
-            pending_user_events,
+            poll,
             display: display.clone(),
             outputs: env.outputs.clone(),
-            _user_source: user_source,
             user_sender,
+            user_channel,
+            kbd_channel,
             cursor_manager,
-            _kbd_source: kbd_source,
             window_target: RootELW {
                 p: crate::platform_impl::EventLoopWindowTarget::Wayland(EventLoopWindowTarget {
-                    evq: RefCell::new(source),
+                    evq: RefCell::new(event_queue),
                     store,
                     env,
                     cursor_manager: cursor_manager_clone,
@@ -458,7 +450,7 @@ impl<T: 'static> EventLoop<T> {
 
     pub fn run<F>(mut self, callback: F) -> !
     where
-        F: 'static + FnMut(crate::event::Event<T>, &RootELW<T>, &mut ControlFlow),
+        F: 'static + FnMut(Event<'_, T>, &RootELW<T>, &mut ControlFlow),
     {
         self.run_return(callback);
         std::process::exit(0);
@@ -466,53 +458,60 @@ impl<T: 'static> EventLoop<T> {
 
     pub fn run_return<F>(&mut self, mut callback: F)
     where
-        F: FnMut(crate::event::Event<T>, &RootELW<T>, &mut ControlFlow),
+        F: FnMut(Event<'_, T>, &RootELW<T>, &mut ControlFlow),
     {
         // send pending events to the server
         self.display.flush().expect("Wayland connection lost.");
 
         let mut control_flow = ControlFlow::default();
-
-        let sink = self.sink.clone();
-        let user_events = self.pending_user_events.clone();
+        let mut events = Events::with_capacity(8);
 
         callback(
-            crate::event::Event::NewEvents(crate::event::StartCause::Init),
+            Event::NewEvents(StartCause::Init),
             &self.window_target,
             &mut control_flow,
         );
 
         loop {
-            self.post_dispatch_triggers();
+            // Read events from the event queue
+            {
+                let mut evq = get_target(&self.window_target).evq.borrow_mut();
 
-            // empty buffer of events
-            {
-                let mut guard = sink.lock().unwrap();
-                guard.empty_with(|evt| {
-                    sticky_exit_callback(
-                        evt,
-                        &self.window_target,
-                        &mut control_flow,
-                        &mut callback,
-                    );
-                });
-            }
-            // empty user events
-            {
-                let mut guard = user_events.borrow_mut();
-                for evt in guard.drain(..) {
-                    sticky_exit_callback(
-                        crate::event::Event::UserEvent(evt),
-                        &self.window_target,
-                        &mut control_flow,
-                        &mut callback,
-                    );
+                evq.dispatch_pending()
+                    .expect("failed to dispatch wayland events");
+
+                if let Some(read) = evq.prepare_read() {
+                    if let Err(e) = read.read_events() {
+                        if e.kind() != ErrorKind::WouldBlock {
+                            panic!("failed to read wayland events: {}", e);
+                        }
+                    }
+
+                    evq.dispatch_pending()
+                        .expect("failed to dispatch wayland events");
                 }
             }
+
+            self.post_dispatch_triggers(&mut callback, &mut control_flow);
+
+            while let Ok(event) = self.kbd_channel.try_recv() {
+                let event = event.map_nonuser_event().unwrap();
+                sticky_exit_callback(event, &self.window_target, &mut control_flow, &mut callback);
+            }
+
+            while let Ok(event) = self.user_channel.try_recv() {
+                sticky_exit_callback(
+                    Event::UserEvent(event),
+                    &self.window_target,
+                    &mut control_flow,
+                    &mut callback,
+                );
+            }
+
             // send Events cleared
             {
                 sticky_exit_callback(
-                    crate::event::Event::MainEventsCleared,
+                    Event::MainEventsCleared,
                     &self.window_target,
                     &mut control_flow,
                     &mut callback,
@@ -523,7 +522,7 @@ impl<T: 'static> EventLoop<T> {
             {
                 self.redraw_triggers(|wid, window_target| {
                     sticky_exit_callback(
-                        crate::event::Event::RedrawRequested(crate::window::WindowId(
+                        Event::RedrawRequested(crate::window::WindowId(
                             crate::platform_impl::WindowId::Wayland(wid),
                         )),
                         window_target,
@@ -536,7 +535,7 @@ impl<T: 'static> EventLoop<T> {
             // send RedrawEventsCleared
             {
                 sticky_exit_callback(
-                    crate::event::Event::RedrawEventsCleared,
+                    Event::RedrawEventsCleared,
                     &self.window_target,
                     &mut control_flow,
                     &mut callback,
@@ -569,24 +568,25 @@ impl<T: 'static> EventLoop<T> {
                 ControlFlow::Exit => break,
                 ControlFlow::Poll => {
                     // non-blocking dispatch
-                    self.inner_loop
-                        .dispatch(Some(::std::time::Duration::from_millis(0)), &mut ())
+                    self.poll
+                        .poll(&mut events, Some(Duration::from_millis(0)))
                         .unwrap();
+                    events.clear();
+
                     callback(
-                        crate::event::Event::NewEvents(crate::event::StartCause::Poll),
+                        Event::NewEvents(StartCause::Poll),
                         &self.window_target,
                         &mut control_flow,
                     );
                 }
                 ControlFlow::Wait => {
-                    let timeout = if instant_wakeup {
-                        Some(::std::time::Duration::from_millis(0))
-                    } else {
-                        None
-                    };
-                    self.inner_loop.dispatch(timeout, &mut ()).unwrap();
+                    if !instant_wakeup {
+                        self.poll.poll(&mut events, None).unwrap();
+                        events.clear();
+                    }
+
                     callback(
-                        crate::event::Event::NewEvents(crate::event::StartCause::WaitCancelled {
+                        Event::NewEvents(StartCause::WaitCancelled {
                             start: Instant::now(),
                             requested_resume: None,
                         }),
@@ -600,29 +600,27 @@ impl<T: 'static> EventLoop<T> {
                     let duration = if deadline > start && !instant_wakeup {
                         deadline - start
                     } else {
-                        ::std::time::Duration::from_millis(0)
+                        Duration::from_millis(0)
                     };
-                    self.inner_loop.dispatch(Some(duration), &mut ()).unwrap();
+                    self.poll.poll(&mut events, Some(duration)).unwrap();
+                    events.clear();
+
                     let now = Instant::now();
                     if now < deadline {
                         callback(
-                            crate::event::Event::NewEvents(
-                                crate::event::StartCause::WaitCancelled {
-                                    start,
-                                    requested_resume: Some(deadline),
-                                },
-                            ),
+                            Event::NewEvents(StartCause::WaitCancelled {
+                                start,
+                                requested_resume: Some(deadline),
+                            }),
                             &self.window_target,
                             &mut control_flow,
                         );
                     } else {
                         callback(
-                            crate::event::Event::NewEvents(
-                                crate::event::StartCause::ResumeTimeReached {
-                                    start,
-                                    requested_resume: deadline,
-                                },
-                            ),
+                            Event::NewEvents(StartCause::ResumeTimeReached {
+                                start,
+                                requested_resume: deadline,
+                            }),
                             &self.window_target,
                             &mut control_flow,
                         );
@@ -631,11 +629,7 @@ impl<T: 'static> EventLoop<T> {
             }
         }
 
-        callback(
-            crate::event::Event::LoopDestroyed,
-            &self.window_target,
-            &mut control_flow,
-        );
+        callback(Event::LoopDestroyed, &self.window_target, &mut control_flow);
     }
 
     pub fn primary_monitor(&self) -> MonitorHandle {
@@ -687,12 +681,19 @@ impl<T> EventLoop<T> {
         )
     }
 
-    fn post_dispatch_triggers(&mut self) {
-        let mut sink = self.sink.lock().unwrap();
+    fn post_dispatch_triggers<F>(&mut self, mut callback: F, control_flow: &mut ControlFlow)
+    where
+        F: FnMut(Event<'_, T>, &RootELW<T>, &mut ControlFlow),
+    {
         let window_target = match self.window_target.p {
             crate::platform_impl::EventLoopWindowTarget::Wayland(ref wt) => wt,
             _ => unreachable!(),
         };
+
+        let mut callback = |event: Event<'_, T>| {
+            sticky_exit_callback(event, &self.window_target, control_flow, &mut callback);
+        };
+
         // prune possible dead windows
         {
             let mut cleanup_needed = window_target.cleanup_needed.lock().unwrap();
@@ -700,41 +701,81 @@ impl<T> EventLoop<T> {
                 let pruned = window_target.store.lock().unwrap().cleanup();
                 *cleanup_needed = false;
                 for wid in pruned {
-                    sink.send_window_event(crate::event::WindowEvent::Destroyed, wid);
+                    callback(Event::WindowEvent {
+                        window_id: crate::window::WindowId(
+                            crate::platform_impl::WindowId::Wayland(wid),
+                        ),
+                        event: WindowEvent::Destroyed,
+                    });
                 }
             }
         }
         // process pending resize/refresh
         window_target.store.lock().unwrap().for_each(|window| {
+            let window_id =
+                crate::window::WindowId(crate::platform_impl::WindowId::Wayland(window.wid));
             if let Some(frame) = window.frame {
-                if let Some(newsize) = window.newsize {
-                    let (w, h) = newsize;
+                if let Some((w, h)) = window.newsize {
+                    // Update decorations state
+                    match window.decorations_action {
+                        Some(DecorationsAction::Hide) => frame.set_decorate(false),
+                        Some(DecorationsAction::Show) => frame.set_decorate(true),
+                        None => (),
+                    }
+
                     // mutter (GNOME Wayland) relies on `set_geometry` to reposition window in case
                     // it overlaps mutter's `bounding box`, so we can't avoid this resize call,
                     // which calls `set_geometry` under the hood, for now.
                     frame.resize(w, h);
                     frame.refresh();
+
                     // Don't send resize event downstream if the new size is identical to the
                     // current one.
-                    if newsize != *window.size {
+                    if (w, h) != *window.size {
                         let logical_size = crate::dpi::LogicalSize::new(w as f64, h as f64);
-                        sink.send_window_event(
-                            crate::event::WindowEvent::Resized(logical_size),
-                            window.wid,
-                        );
+                        let physical_size = logical_size
+                            .to_physical(window.new_dpi.unwrap_or(window.prev_dpi) as f64);
 
+                        callback(Event::WindowEvent {
+                            window_id,
+                            event: WindowEvent::Resized(physical_size),
+                        });
                         *window.size = (w, h);
                     }
                 }
-            }
-            if let Some(dpi) = window.new_dpi {
-                sink.send_window_event(
-                    crate::event::WindowEvent::HiDpiFactorChanged(dpi as f64),
-                    window.wid,
-                );
+
+                if let Some(dpi) = window.new_dpi {
+                    // Update cursor scale factor
+                    {
+                        self.cursor_manager
+                            .lock()
+                            .unwrap()
+                            .update_scale_factor(dpi as u32);
+                    };
+                    let dpi = dpi as f64;
+                    let logical_size = LogicalSize::<f64>::from(*window.size);
+                    let mut new_inner_size = logical_size.to_physical(dpi);
+
+                    callback(Event::WindowEvent {
+                        window_id,
+                        event: WindowEvent::ScaleFactorChanged {
+                            scale_factor: dpi,
+                            new_inner_size: &mut new_inner_size,
+                        },
+                    });
+
+                    let (w, h) = new_inner_size.to_logical::<u32>(dpi).into();
+                    frame.resize(w, h);
+                    // Refresh frame to rescale decorations
+                    frame.refresh();
+                    *window.size = (w, h);
+                }
             }
             if window.closed {
-                sink.send_window_event(crate::event::WindowEvent::CloseRequested, window.wid);
+                callback(Event::WindowEvent {
+                    window_id,
+                    event: WindowEvent::CloseRequested,
+                });
             }
 
             if let Some(grab_cursor) = window.grab_cursor {
@@ -749,21 +790,27 @@ impl<T> EventLoop<T> {
     }
 }
 
+fn get_target<T>(target: &RootELW<T>) -> &EventLoopWindowTarget<T> {
+    match target.p {
+        crate::platform_impl::EventLoopWindowTarget::Wayland(ref wt) => wt,
+        _ => unreachable!(),
+    }
+}
+
 /*
  * Wayland protocol implementations
  */
 
-struct SeatManager<T: 'static> {
-    sink: Arc<Mutex<WindowEventsSink<T>>>,
+struct SeatManager {
+    sink: EventsSink,
     store: Arc<Mutex<WindowStore>>,
     seats: Arc<Mutex<Vec<(u32, wl_seat::WlSeat)>>>,
-    kbd_sender: ::calloop::channel::Sender<crate::event::Event<()>>,
     relative_pointer_manager_proxy: Rc<RefCell<Option<ZwpRelativePointerManagerV1>>>,
     pointer_constraints_proxy: Arc<Mutex<Option<ZwpPointerConstraintsV1>>>,
     cursor_manager: Arc<Mutex<CursorManager>>,
 }
 
-impl<T: 'static> SeatManager<T> {
+impl SeatManager {
     fn add_seat(&mut self, id: u32, version: u32, registry: wl_registry::WlRegistry) {
         use std::cmp::min;
 
@@ -775,7 +822,6 @@ impl<T: 'static> SeatManager<T> {
             relative_pointer_manager_proxy: self.relative_pointer_manager_proxy.clone(),
             keyboard: None,
             touch: None,
-            kbd_sender: self.kbd_sender.clone(),
             modifiers_tracker: Arc::new(Mutex::new(ModifiersState::default())),
             cursor_manager: self.cursor_manager.clone(),
         };
@@ -799,10 +845,9 @@ impl<T: 'static> SeatManager<T> {
     }
 }
 
-struct SeatData<T> {
-    sink: Arc<Mutex<WindowEventsSink<T>>>,
+struct SeatData {
+    sink: EventsSink,
     store: Arc<Mutex<WindowStore>>,
-    kbd_sender: ::calloop::channel::Sender<crate::event::Event<()>>,
     pointer: Option<wl_pointer::WlPointer>,
     relative_pointer: Option<ZwpRelativePointerV1>,
     relative_pointer_manager_proxy: Rc<RefCell<Option<ZwpRelativePointerManagerV1>>>,
@@ -812,7 +857,7 @@ struct SeatData<T> {
     cursor_manager: Arc<Mutex<CursorManager>>,
 }
 
-impl<T: 'static> SeatData<T> {
+impl SeatData {
     fn receive(&mut self, evt: wl_seat::Event, seat: wl_seat::WlSeat) {
         match evt {
             wl_seat::Event::Name { .. } => (),
@@ -858,7 +903,7 @@ impl<T: 'static> SeatData<T> {
                 if capabilities.contains(wl_seat::Capability::Keyboard) && self.keyboard.is_none() {
                     self.keyboard = Some(super::keyboard::init_keyboard(
                         &seat,
-                        self.kbd_sender.clone(),
+                        self.sink.clone(),
                         self.modifiers_tracker.clone(),
                     ))
                 }
@@ -892,7 +937,7 @@ impl<T: 'static> SeatData<T> {
     }
 }
 
-impl<T> Drop for SeatData<T> {
+impl Drop for SeatData {
     fn drop(&mut self) {
         if let Some(pointer) = self.pointer.take() {
             if pointer.as_ref().version() >= 3 {
@@ -926,7 +971,7 @@ pub struct VideoMode {
 
 impl VideoMode {
     #[inline]
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         self.size.into()
     }
 
@@ -986,9 +1031,9 @@ impl fmt::Debug for MonitorHandle {
         struct MonitorHandle {
             name: Option<String>,
             native_identifier: u32,
-            size: PhysicalSize,
-            position: PhysicalPosition,
-            hidpi_factor: i32,
+            size: PhysicalSize<u32>,
+            position: PhysicalPosition<i32>,
+            scale_factor: i32,
         }
 
         let monitor_id_proxy = MonitorHandle {
@@ -996,7 +1041,7 @@ impl fmt::Debug for MonitorHandle {
             native_identifier: self.native_identifier(),
             size: self.size(),
             position: self.position(),
-            hidpi_factor: self.hidpi_factor(),
+            scale_factor: self.scale_factor(),
         };
 
         monitor_id_proxy.fmt(f)
@@ -1015,7 +1060,7 @@ impl MonitorHandle {
         self.mgr.with_info(&self.proxy, |id, _| id).unwrap_or(0)
     }
 
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         match self.mgr.with_info(&self.proxy, |_, info| {
             info.modes
                 .iter()
@@ -1028,7 +1073,7 @@ impl MonitorHandle {
         .into()
     }
 
-    pub fn position(&self) -> PhysicalPosition {
+    pub fn position(&self) -> PhysicalPosition<i32> {
         self.mgr
             .with_info(&self.proxy, |_, info| info.location)
             .unwrap_or((0, 0))
@@ -1036,7 +1081,7 @@ impl MonitorHandle {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> i32 {
+    pub fn scale_factor(&self) -> i32 {
         self.mgr
             .with_info(&self.proxy, |_, info| info.scale_factor)
             .unwrap_or(1)

src/platform_impl/linux/wayland/keyboard.rs

@@ -1,6 +1,6 @@
 use std::sync::{Arc, Mutex};
 
-use super::{make_wid, DeviceId};
+use super::{event_loop::EventsSink, make_wid, DeviceId};
 use smithay_client_toolkit::{
     keyboard::{
         self, map_keyboard_auto_with_repeat, Event as KbEvent, KeyRepeatEvent, KeyRepeatKind,
@@ -8,13 +8,11 @@ use smithay_client_toolkit::{
     reexports::client::protocol::{wl_keyboard, wl_seat},
 };
 
-use crate::event::{
-    DeviceEvent, ElementState, Event, KeyboardInput, ModifiersState, VirtualKeyCode, WindowEvent,
-};
+use crate::event::{ElementState, KeyboardInput, ModifiersState, VirtualKeyCode, WindowEvent};
 
 pub fn init_keyboard(
     seat: &wl_seat::WlSeat,
-    sink: ::calloop::channel::Sender<crate::event::Event<()>>,
+    sink: EventsSink,
     modifiers_tracker: Arc<Mutex<ModifiersState>>,
 ) -> wl_keyboard::WlKeyboard {
     // { variables to be captured by the closures
@@ -31,22 +29,27 @@ pub fn init_keyboard(
             match evt {
                 KbEvent::Enter { surface, .. } => {
                     let wid = make_wid(&surface);
-                    my_sink
-                        .send(Event::WindowEvent {
-                            window_id: mk_root_wid(wid),
-                            event: WindowEvent::Focused(true),
-                        })
-                        .unwrap();
+                    my_sink.send_window_event(WindowEvent::Focused(true), wid);
                     *target.lock().unwrap() = Some(wid);
+
+                    let modifiers = *modifiers_tracker.lock().unwrap();
+
+                    if !modifiers.is_empty() {
+                        my_sink.send_window_event(WindowEvent::ModifiersChanged(modifiers), wid);
+                    }
                 }
                 KbEvent::Leave { surface, .. } => {
                     let wid = make_wid(&surface);
-                    my_sink
-                        .send(Event::WindowEvent {
-                            window_id: mk_root_wid(wid),
-                            event: WindowEvent::Focused(false),
-                        })
-                        .unwrap();
+                    let modifiers = *modifiers_tracker.lock().unwrap();
+
+                    if !modifiers.is_empty() {
+                        my_sink.send_window_event(
+                            WindowEvent::ModifiersChanged(ModifiersState::empty()),
+                            wid,
+                        );
+                    }
+
+                    my_sink.send_window_event(WindowEvent::Focused(false), wid);
                     *target.lock().unwrap() = None;
                 }
                 KbEvent::Key {
@@ -63,33 +66,29 @@ pub fn init_keyboard(
                             _ => unreachable!(),
                         };
                         let vkcode = key_to_vkey(rawkey, keysym);
-                        my_sink
-                            .send(Event::WindowEvent {
-                                window_id: mk_root_wid(wid),
-                                event: WindowEvent::KeyboardInput {
-                                    device_id: device_id(),
-                                    input: KeyboardInput {
-                                        state,
-                                        scancode: rawkey,
-                                        virtual_keycode: vkcode,
-                                        modifiers: modifiers_tracker.lock().unwrap().clone(),
-                                    },
-                                    is_synthetic: false,
+                        my_sink.send_window_event(
+                            #[allow(deprecated)]
+                            WindowEvent::KeyboardInput {
+                                device_id: crate::event::DeviceId(
+                                    crate::platform_impl::DeviceId::Wayland(DeviceId),
+                                ),
+                                input: KeyboardInput {
+                                    state,
+                                    scancode: rawkey,
+                                    virtual_keycode: vkcode,
+                                    modifiers: modifiers_tracker.lock().unwrap().clone(),
                                 },
-                            })
-                            .unwrap();
+                                is_synthetic: false,
+                            },
+                            wid,
+                        );
                         // send char event only on key press, not release
                         if let ElementState::Released = state {
                             return;
                         }
                         if let Some(txt) = utf8 {
                             for chr in txt.chars() {
-                                my_sink
-                                    .send(Event::WindowEvent {
-                                        window_id: mk_root_wid(wid),
-                                        event: WindowEvent::ReceivedCharacter(chr),
-                                    })
-                                    .unwrap();
+                                my_sink.send_window_event(WindowEvent::ReceivedCharacter(chr), wid);
                             }
                         }
                     }
@@ -102,12 +101,9 @@ pub fn init_keyboard(
 
                     *modifiers_tracker.lock().unwrap() = modifiers;
 
-                    my_sink
-                        .send(Event::DeviceEvent {
-                            device_id: device_id(),
-                            event: DeviceEvent::ModifiersChanged(modifiers),
-                        })
-                        .unwrap();
+                    if let Some(wid) = *target.lock().unwrap() {
+                        my_sink.send_window_event(WindowEvent::ModifiersChanged(modifiers), wid);
+                    }
                 }
             }
         },
@@ -115,29 +111,25 @@ pub fn init_keyboard(
             if let Some(wid) = *repeat_target.lock().unwrap() {
                 let state = ElementState::Pressed;
                 let vkcode = key_to_vkey(repeat_event.rawkey, repeat_event.keysym);
-                repeat_sink
-                    .send(Event::WindowEvent {
-                        window_id: mk_root_wid(wid),
-                        event: WindowEvent::KeyboardInput {
-                            device_id: device_id(),
-                            input: KeyboardInput {
-                                state,
-                                scancode: repeat_event.rawkey,
-                                virtual_keycode: vkcode,
-                                modifiers: my_modifiers.lock().unwrap().clone(),
-                            },
-                            is_synthetic: false,
+                repeat_sink.send_window_event(
+                    #[allow(deprecated)]
+                    WindowEvent::KeyboardInput {
+                        device_id: crate::event::DeviceId(crate::platform_impl::DeviceId::Wayland(
+                            DeviceId,
+                        )),
+                        input: KeyboardInput {
+                            state,
+                            scancode: repeat_event.rawkey,
+                            virtual_keycode: vkcode,
+                            modifiers: my_modifiers.lock().unwrap().clone(),
                         },
-                    })
-                    .unwrap();
+                        is_synthetic: false,
+                    },
+                    wid,
+                );
                 if let Some(txt) = repeat_event.utf8 {
                     for chr in txt.chars() {
-                        repeat_sink
-                            .send(Event::WindowEvent {
-                                window_id: mk_root_wid(wid),
-                                event: WindowEvent::ReceivedCharacter(chr),
-                            })
-                            .unwrap();
+                        repeat_sink.send_window_event(WindowEvent::ReceivedCharacter(chr), wid);
                     }
                 }
             }
@@ -164,22 +156,12 @@ pub fn init_keyboard(
                     move |evt, _| match evt {
                         wl_keyboard::Event::Enter { surface, .. } => {
                             let wid = make_wid(&surface);
-                            my_sink
-                                .send(Event::WindowEvent {
-                                    window_id: mk_root_wid(wid),
-                                    event: WindowEvent::Focused(true),
-                                })
-                                .unwrap();
+                            my_sink.send_window_event(WindowEvent::Focused(true), wid);
                             target = Some(wid);
                         }
                         wl_keyboard::Event::Leave { surface, .. } => {
                             let wid = make_wid(&surface);
-                            my_sink
-                                .send(Event::WindowEvent {
-                                    window_id: mk_root_wid(wid),
-                                    event: WindowEvent::Focused(false),
-                                })
-                                .unwrap();
+                            my_sink.send_window_event(WindowEvent::Focused(false), wid);
                             target = None;
                         }
                         wl_keyboard::Event::Key { key, state, .. } => {
@@ -189,21 +171,22 @@ pub fn init_keyboard(
                                     wl_keyboard::KeyState::Released => ElementState::Released,
                                     _ => unreachable!(),
                                 };
-                                my_sink
-                                    .send(Event::WindowEvent {
-                                        window_id: mk_root_wid(wid),
-                                        event: WindowEvent::KeyboardInput {
-                                            device_id: device_id(),
-                                            input: KeyboardInput {
-                                                state,
-                                                scancode: key,
-                                                virtual_keycode: None,
-                                                modifiers: ModifiersState::default(),
-                                            },
-                                            is_synthetic: false,
+                                my_sink.send_window_event(
+                                    #[allow(deprecated)]
+                                    WindowEvent::KeyboardInput {
+                                        device_id: crate::event::DeviceId(
+                                            crate::platform_impl::DeviceId::Wayland(DeviceId),
+                                        ),
+                                        input: KeyboardInput {
+                                            state,
+                                            scancode: key,
+                                            virtual_keycode: None,
+                                            modifiers: ModifiersState::default(),
                                         },
-                                    })
-                                    .unwrap();
+                                        is_synthetic: false,
+                                    },
+                                    wid,
+                                );
                             }
                         }
                         _ => (),
@@ -412,11 +395,3 @@ impl ModifiersState {
         m
     }
 }
-
-fn device_id() -> crate::event::DeviceId {
-    crate::event::DeviceId(crate::platform_impl::DeviceId::Wayland(DeviceId))
-}
-
-fn mk_root_wid(wid: crate::platform_impl::wayland::WindowId) -> crate::window::WindowId {
-    crate::window::WindowId(crate::platform_impl::WindowId::Wayland(wid))
-}

src/platform_impl/linux/wayland/mod.rs

@@ -2,10 +2,7 @@
            target_os = "netbsd", target_os = "openbsd"))]
 
 pub use self::{
-    event_loop::{
-        EventLoop, EventLoopProxy, EventLoopWindowTarget, MonitorHandle, VideoMode,
-        WindowEventsSink,
-    },
+    event_loop::{EventLoop, EventLoopProxy, EventLoopWindowTarget, MonitorHandle, VideoMode},
     window::Window,
 };
 

src/platform_impl/linux/wayland/pointer.rs

@@ -1,16 +1,20 @@
 use std::sync::{Arc, Mutex};
 
+use crate::dpi::LogicalPosition;
 use crate::event::{
     DeviceEvent, ElementState, ModifiersState, MouseButton, MouseScrollDelta, TouchPhase,
     WindowEvent,
 };
 
 use super::{
-    event_loop::{CursorManager, WindowEventsSink},
+    event_loop::{CursorManager, EventsSink},
+    make_wid,
     window::WindowStore,
     DeviceId,
 };
 
+use smithay_client_toolkit::surface;
+
 use smithay_client_toolkit::reexports::client::protocol::{
     wl_pointer::{self, Event as PtrEvent, WlPointer},
     wl_seat,
@@ -28,14 +32,15 @@ use smithay_client_toolkit::reexports::protocols::unstable::pointer_constraints:
 
 use smithay_client_toolkit::reexports::client::protocol::wl_surface::WlSurface;
 
-pub fn implement_pointer<T: 'static>(
+pub fn implement_pointer(
     seat: &wl_seat::WlSeat,
-    sink: Arc<Mutex<WindowEventsSink<T>>>,
+    sink: EventsSink,
     store: Arc<Mutex<WindowStore>>,
     modifiers_tracker: Arc<Mutex<ModifiersState>>,
     cursor_manager: Arc<Mutex<CursorManager>>,
 ) -> WlPointer {
     seat.get_pointer(|pointer| {
+        // Currently focused winit surface
         let mut mouse_focus = None;
         let mut axis_buffer = None;
         let mut axis_discrete_buffer = None;
@@ -43,7 +48,6 @@ pub fn implement_pointer<T: 'static>(
 
         pointer.implement_closure(
             move |evt, pointer| {
-                let mut sink = sink.lock().unwrap();
                 let store = store.lock().unwrap();
                 let mut cursor_manager = cursor_manager.lock().unwrap();
                 match evt {
@@ -54,8 +58,10 @@ pub fn implement_pointer<T: 'static>(
                         ..
                     } => {
                         let wid = store.find_wid(&surface);
+
                         if let Some(wid) = wid {
-                            mouse_focus = Some(wid);
+                            let scale_factor = surface::get_dpi_factor(&surface) as f64;
+                            mouse_focus = Some(surface);
 
                             // Reload cursor style only when we enter winit's surface. Calling
                             // this function every time on `PtrEvent::Enter` could interfere with
@@ -71,12 +77,16 @@ pub fn implement_pointer<T: 'static>(
                                 },
                                 wid,
                             );
+
+                            let position = LogicalPosition::new(surface_x, surface_y)
+                                .to_physical(scale_factor);
+
                             sink.send_window_event(
                                 WindowEvent::CursorMoved {
                                     device_id: crate::event::DeviceId(
                                         crate::platform_impl::DeviceId::Wayland(DeviceId),
                                     ),
-                                    position: (surface_x, surface_y).into(),
+                                    position,
                                     modifiers: modifiers_tracker.lock().unwrap().clone(),
                                 },
                                 wid,
@@ -102,13 +112,19 @@ pub fn implement_pointer<T: 'static>(
                         surface_y,
                         ..
                     } => {
-                        if let Some(wid) = mouse_focus {
+                        if let Some(surface) = mouse_focus.as_ref() {
+                            let wid = make_wid(surface);
+
+                            let scale_factor = surface::get_dpi_factor(&surface) as f64;
+                            let position = LogicalPosition::new(surface_x, surface_y)
+                                .to_physical(scale_factor);
+
                             sink.send_window_event(
                                 WindowEvent::CursorMoved {
                                     device_id: crate::event::DeviceId(
                                         crate::platform_impl::DeviceId::Wayland(DeviceId),
                                     ),
-                                    position: (surface_x, surface_y).into(),
+                                    position,
                                     modifiers: modifiers_tracker.lock().unwrap().clone(),
                                 },
                                 wid,
@@ -116,7 +132,7 @@ pub fn implement_pointer<T: 'static>(
                         }
                     }
                     PtrEvent::Button { button, state, .. } => {
-                        if let Some(wid) = mouse_focus {
+                        if let Some(surface) = mouse_focus.as_ref() {
                             let state = match state {
                                 wl_pointer::ButtonState::Pressed => ElementState::Pressed,
                                 wl_pointer::ButtonState::Released => ElementState::Released,
@@ -138,12 +154,13 @@ pub fn implement_pointer<T: 'static>(
                                     button,
                                     modifiers: modifiers_tracker.lock().unwrap().clone(),
                                 },
-                                wid,
+                                make_wid(surface),
                             );
                         }
                     }
                     PtrEvent::Axis { axis, value, .. } => {
-                        if let Some(wid) = mouse_focus {
+                        if let Some(surface) = mouse_focus.as_ref() {
+                            let wid = make_wid(surface);
                             if pointer.as_ref().version() < 5 {
                                 let (mut x, mut y) = (0.0, 0.0);
                                 // old seat compatibility
@@ -185,7 +202,8 @@ pub fn implement_pointer<T: 'static>(
                     PtrEvent::Frame => {
                         let axis_buffer = axis_buffer.take();
                         let axis_discrete_buffer = axis_discrete_buffer.take();
-                        if let Some(wid) = mouse_focus {
+                        if let Some(surface) = mouse_focus.as_ref() {
+                            let wid = make_wid(surface);
                             if let Some((x, y)) = axis_discrete_buffer {
                                 sink.send_window_event(
                                     WindowEvent::MouseWheel {
@@ -242,20 +260,18 @@ pub fn implement_pointer<T: 'static>(
     .unwrap()
 }
 
-pub fn implement_relative_pointer<T: 'static>(
-    sink: Arc<Mutex<WindowEventsSink<T>>>,
+pub fn implement_relative_pointer(
+    sink: EventsSink,
     pointer: &WlPointer,
     manager: &ZwpRelativePointerManagerV1,
 ) -> Result<ZwpRelativePointerV1, ()> {
     manager.get_relative_pointer(pointer, |rel_pointer| {
         rel_pointer.implement_closure(
-            move |evt, _rel_pointer| {
-                let mut sink = sink.lock().unwrap();
-                match evt {
-                    Event::RelativeMotion { dx, dy, .. } => sink
-                        .send_device_event(DeviceEvent::MouseMotion { delta: (dx, dy) }, DeviceId),
-                    _ => unreachable!(),
+            move |evt, _rel_pointer| match evt {
+                Event::RelativeMotion { dx, dy, .. } => {
+                    sink.send_device_event(DeviceEvent::MouseMotion { delta: (dx, dy) }, DeviceId)
                 }
+                _ => unreachable!(),
             },
             (),
         )

src/platform_impl/linux/wayland/touch.rs

@@ -1,30 +1,34 @@
 use std::sync::{Arc, Mutex};
 
+use crate::dpi::LogicalPosition;
 use crate::event::{TouchPhase, WindowEvent};
 
-use super::{event_loop::WindowEventsSink, window::WindowStore, DeviceId, WindowId};
+use super::{event_loop::EventsSink, make_wid, window::WindowStore, DeviceId};
+
+use smithay_client_toolkit::surface;
 
 use smithay_client_toolkit::reexports::client::protocol::{
     wl_seat,
+    wl_surface::WlSurface,
     wl_touch::{Event as TouchEvent, WlTouch},
 };
 
+// location is in logical coordinates.
 struct TouchPoint {
-    wid: WindowId,
-    location: (f64, f64),
+    surface: WlSurface,
+    position: LogicalPosition<f64>,
     id: i32,
 }
 
-pub(crate) fn implement_touch<T: 'static>(
+pub(crate) fn implement_touch(
     seat: &wl_seat::WlSeat,
-    sink: Arc<Mutex<WindowEventsSink<T>>>,
+    sink: EventsSink,
     store: Arc<Mutex<WindowStore>>,
 ) -> WlTouch {
     let mut pending_ids = Vec::new();
     seat.get_touch(|touch| {
         touch.implement_closure(
             move |evt, _| {
-                let mut sink = sink.lock().unwrap();
                 let store = store.lock().unwrap();
                 match evt {
                     TouchEvent::Down {
@@ -32,21 +36,24 @@ pub(crate) fn implement_touch<T: 'static>(
                     } => {
                         let wid = store.find_wid(&surface);
                         if let Some(wid) = wid {
+                            let scale_factor = surface::get_dpi_factor(&surface) as f64;
+                            let position = LogicalPosition::new(x, y);
+
                             sink.send_window_event(
                                 WindowEvent::Touch(crate::event::Touch {
                                     device_id: crate::event::DeviceId(
                                         crate::platform_impl::DeviceId::Wayland(DeviceId),
                                     ),
                                     phase: TouchPhase::Started,
-                                    location: (x, y).into(),
+                                    location: position.to_physical(scale_factor),
                                     force: None, // TODO
                                     id: id as u64,
                                 }),
                                 wid,
                             );
                             pending_ids.push(TouchPoint {
-                                wid,
-                                location: (x, y),
+                                surface,
+                                position,
                                 id,
                             });
                         }
@@ -55,52 +62,63 @@ pub(crate) fn implement_touch<T: 'static>(
                         let idx = pending_ids.iter().position(|p| p.id == id);
                         if let Some(idx) = idx {
                             let pt = pending_ids.remove(idx);
+
+                            let scale_factor = surface::get_dpi_factor(&pt.surface) as f64;
+                            let location = pt.position.to_physical(scale_factor);
+
                             sink.send_window_event(
                                 WindowEvent::Touch(crate::event::Touch {
                                     device_id: crate::event::DeviceId(
                                         crate::platform_impl::DeviceId::Wayland(DeviceId),
                                     ),
                                     phase: TouchPhase::Ended,
-                                    location: pt.location.into(),
+                                    location,
                                     force: None, // TODO
                                     id: id as u64,
                                 }),
-                                pt.wid,
+                                make_wid(&pt.surface),
                             );
                         }
                     }
                     TouchEvent::Motion { id, x, y, .. } => {
                         let pt = pending_ids.iter_mut().find(|p| p.id == id);
                         if let Some(pt) = pt {
-                            pt.location = (x, y);
+                            pt.position = LogicalPosition::new(x, y);
+
+                            let scale_factor = surface::get_dpi_factor(&pt.surface) as f64;
+                            let location = pt.position.to_physical(scale_factor);
+
                             sink.send_window_event(
                                 WindowEvent::Touch(crate::event::Touch {
                                     device_id: crate::event::DeviceId(
                                         crate::platform_impl::DeviceId::Wayland(DeviceId),
                                     ),
                                     phase: TouchPhase::Moved,
-                                    location: (x, y).into(),
+                                    location,
                                     force: None, // TODO
                                     id: id as u64,
                                 }),
-                                pt.wid,
+                                make_wid(&pt.surface),
                             );
                         }
                     }
                     TouchEvent::Frame => (),
                     TouchEvent::Cancel => {
                         for pt in pending_ids.drain(..) {
+                            let scale_factor = surface::get_dpi_factor(&pt.surface) as f64;
+                            let location = pt.position.to_physical(scale_factor);
+
                             sink.send_window_event(
                                 WindowEvent::Touch(crate::event::Touch {
                                     device_id: crate::event::DeviceId(
                                         crate::platform_impl::DeviceId::Wayland(DeviceId),
                                     ),
                                     phase: TouchPhase::Cancelled,
-                                    location: pt.location.into(),
+                                    location,
                                     force: None, // TODO
                                     id: pt.id as u64,
                                 }),
-                                pt.wid,
+                                make_wid(&pt.surface),
                             );
                         }
                     }

src/platform_impl/linux/wayland/window.rs

@@ -6,7 +6,7 @@ use std::{
 };
 
 use crate::{
-    dpi::{LogicalPosition, LogicalSize},
+    dpi::{LogicalSize, PhysicalPosition, PhysicalSize, Position, Size},
     error::{ExternalError, NotSupportedError, OsError as RootOsError},
     monitor::MonitorHandle as RootMonitorHandle,
     platform_impl::{
@@ -41,6 +41,13 @@ pub struct Window {
     need_refresh: Arc<Mutex<bool>>,
     fullscreen: Arc<Mutex<bool>>,
     cursor_grab_changed: Arc<Mutex<Option<bool>>>, // Update grab state
+    decorated: Arc<Mutex<bool>>,
+}
+
+#[derive(Clone, Copy, Debug)]
+pub enum DecorationsAction {
+    Hide,
+    Show,
 }
 
 impl Window {
@@ -49,11 +56,7 @@ impl Window {
         attributes: WindowAttributes,
         pl_attribs: PlAttributes,
     ) -> Result<Window, RootOsError> {
-        let (width, height) = attributes.inner_size.map(Into::into).unwrap_or((800, 600));
-        // Create the window
-        let size = Arc::new(Mutex::new((width, height)));
-        let fullscreen = Arc::new(Mutex::new(false));
-
+        // Create the surface first to get initial DPI
         let window_store = evlp.store.clone();
         let cursor_manager = evlp.cursor_manager.clone();
         let surface = evlp.env.create_surface(move |dpi, surface| {
@@ -61,7 +64,21 @@ impl Window {
             surface.set_buffer_scale(dpi);
         });
 
+        let dpi = get_dpi_factor(&surface) as f64;
+        let (width, height) = attributes
+            .inner_size
+            .map(|size| size.to_logical::<f64>(dpi).into())
+            .unwrap_or((800, 600));
+
+        // Create the window
+        let size = Arc::new(Mutex::new((width, height)));
+        let fullscreen = Arc::new(Mutex::new(false));
+
         let window_store = evlp.store.clone();
+
+        let decorated = Arc::new(Mutex::new(attributes.decorations));
+        let pending_decorations_action = Arc::new(Mutex::new(None));
+
         let my_surface = surface.clone();
         let mut frame = SWindow::<ConceptFrame>::init_from_env(
             &evlp.env,
@@ -76,7 +93,23 @@ impl Window {
                         if window.surface.as_ref().equals(&my_surface.as_ref()) {
                             window.newsize = new_size;
                             *(window.need_refresh.lock().unwrap()) = true;
-                            *(window.fullscreen.lock().unwrap()) = is_fullscreen;
+                            {
+                                // Get whether we're in fullscreen
+                                let mut fullscreen = window.fullscreen.lock().unwrap();
+                                // Fullscreen state was changed, so update decorations
+                                if *fullscreen != is_fullscreen {
+                                    let decorated = { *window.decorated.lock().unwrap() };
+                                    if decorated {
+                                        *window.pending_decorations_action.lock().unwrap() =
+                                            if is_fullscreen {
+                                                Some(DecorationsAction::Hide)
+                                            } else {
+                                                Some(DecorationsAction::Show)
+                                            };
+                                    }
+                                }
+                                *fullscreen = is_fullscreen;
+                            }
                             *(window.need_frame_refresh.lock().unwrap()) = true;
                             return;
                         }
@@ -137,8 +170,16 @@ impl Window {
         frame.set_title(attributes.title);
 
         // min-max dimensions
-        frame.set_min_size(attributes.min_inner_size.map(Into::into));
-        frame.set_max_size(attributes.max_inner_size.map(Into::into));
+        frame.set_min_size(
+            attributes
+                .min_inner_size
+                .map(|size| size.to_logical::<f64>(dpi).into()),
+        );
+        frame.set_max_size(
+            attributes
+                .max_inner_size
+                .map(|size| size.to_logical::<f64>(dpi).into()),
+        );
 
         let kill_switch = Arc::new(Mutex::new(false));
         let need_frame_refresh = Arc::new(Mutex::new(true));
@@ -159,6 +200,8 @@ impl Window {
             frame: Arc::downgrade(&frame),
             current_dpi: 1,
             new_dpi: None,
+            decorated: decorated.clone(),
+            pending_decorations_action: pending_decorations_action.clone(),
         });
         evlp.evq.borrow_mut().sync_roundtrip().unwrap();
 
@@ -174,6 +217,7 @@ impl Window {
             cursor_manager,
             fullscreen,
             cursor_grab_changed,
+            decorated,
         })
     }
 
@@ -191,22 +235,24 @@ impl Window {
     }
 
     #[inline]
-    pub fn outer_position(&self) -> Result<LogicalPosition, NotSupportedError> {
+    pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         Err(NotSupportedError::new())
     }
 
     #[inline]
-    pub fn inner_position(&self) -> Result<LogicalPosition, NotSupportedError> {
+    pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         Err(NotSupportedError::new())
     }
 
     #[inline]
-    pub fn set_outer_position(&self, _pos: LogicalPosition) {
+    pub fn set_outer_position(&self, _pos: Position) {
         // Not possible with wayland
     }
 
-    pub fn inner_size(&self) -> LogicalSize {
-        self.size.lock().unwrap().clone().into()
+    pub fn inner_size(&self) -> PhysicalSize<u32> {
+        let dpi = self.scale_factor() as f64;
+        let size = LogicalSize::<f64>::from(*self.size.lock().unwrap());
+        size.to_physical(dpi)
     }
 
     pub fn request_redraw(&self) {
@@ -214,34 +260,39 @@ impl Window {
     }
 
     #[inline]
-    pub fn outer_size(&self) -> LogicalSize {
+    pub fn outer_size(&self) -> PhysicalSize<u32> {
+        let dpi = self.scale_factor() as f64;
         let (w, h) = self.size.lock().unwrap().clone();
         // let (w, h) = super::wayland_window::add_borders(w as i32, h as i32);
-        (w, h).into()
+        let size = LogicalSize::<f64>::from((w, h));
+        size.to_physical(dpi)
     }
 
     #[inline]
     // NOTE: This will only resize the borders, the contents must be updated by the user
-    pub fn set_inner_size(&self, size: LogicalSize) {
-        let (w, h) = size.into();
+    pub fn set_inner_size(&self, size: Size) {
+        let dpi = self.scale_factor() as f64;
+        let (w, h) = size.to_logical::<u32>(dpi).into();
         self.frame.lock().unwrap().resize(w, h);
         *(self.size.lock().unwrap()) = (w, h);
     }
 
     #[inline]
-    pub fn set_min_inner_size(&self, dimensions: Option<LogicalSize>) {
+    pub fn set_min_inner_size(&self, dimensions: Option<Size>) {
+        let dpi = self.scale_factor() as f64;
         self.frame
             .lock()
             .unwrap()
-            .set_min_size(dimensions.map(Into::into));
+            .set_min_size(dimensions.map(|dim| dim.to_logical::<f64>(dpi).into()));
     }
 
     #[inline]
-    pub fn set_max_inner_size(&self, dimensions: Option<LogicalSize>) {
+    pub fn set_max_inner_size(&self, dimensions: Option<Size>) {
+        let dpi = self.scale_factor() as f64;
         self.frame
             .lock()
             .unwrap()
-            .set_max_size(dimensions.map(Into::into));
+            .set_max_size(dimensions.map(|dim| dim.to_logical::<f64>(dpi).into()));
     }
 
     #[inline]
@@ -250,11 +301,12 @@ impl Window {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> i32 {
+    pub fn scale_factor(&self) -> i32 {
         get_dpi_factor(&self.surface)
     }
 
     pub fn set_decorations(&self, decorate: bool) {
+        *(self.decorated.lock().unwrap()) = decorate;
         self.frame.lock().unwrap().set_decorate(decorate);
         *(self.need_frame_refresh.lock().unwrap()) = true;
     }
@@ -325,7 +377,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, _pos: LogicalPosition) -> Result<(), ExternalError> {
+    pub fn set_cursor_position(&self, _pos: Position) -> Result<(), ExternalError> {
         Err(ExternalError::NotSupported(NotSupportedError::new()))
     }
 
@@ -375,6 +427,7 @@ impl Drop for Window {
 
 struct InternalWindow {
     surface: wl_surface::WlSurface,
+    // TODO: CONVERT TO LogicalSize<u32>s
     newsize: Option<(u32, u32)>,
     size: Arc<Mutex<(u32, u32)>>,
     need_refresh: Arc<Mutex<bool>>,
@@ -386,6 +439,8 @@ struct InternalWindow {
     frame: Weak<Mutex<SWindow<ConceptFrame>>>,
     current_dpi: i32,
     new_dpi: Option<i32>,
+    decorated: Arc<Mutex<bool>>,
+    pending_decorations_action: Arc<Mutex<Option<DecorationsAction>>>,
 }
 
 pub struct WindowStore {
@@ -395,12 +450,14 @@ pub struct WindowStore {
 pub struct WindowStoreForEach<'a> {
     pub newsize: Option<(u32, u32)>,
     pub size: &'a mut (u32, u32),
+    pub prev_dpi: i32,
     pub new_dpi: Option<i32>,
     pub closed: bool,
     pub grab_cursor: Option<bool>,
     pub surface: &'a wl_surface::WlSurface,
     pub wid: WindowId,
     pub frame: Option<&'a mut SWindow<ConceptFrame>>,
+    pub decorations_action: Option<DecorationsAction>,
 }
 
 impl WindowStore {
@@ -457,16 +514,21 @@ impl WindowStore {
         for window in &mut self.windows {
             let opt_arc = window.frame.upgrade();
             let mut opt_mutex_lock = opt_arc.as_ref().map(|m| m.lock().unwrap());
+            let mut size = { *window.size.lock().unwrap() };
+            let decorations_action = { window.pending_decorations_action.lock().unwrap().take() };
             f(WindowStoreForEach {
                 newsize: window.newsize.take(),
-                size: &mut *(window.size.lock().unwrap()),
+                size: &mut size,
+                prev_dpi: window.current_dpi,
                 new_dpi: window.new_dpi,
                 closed: window.closed,
                 grab_cursor: window.cursor_grab_changed.lock().unwrap().take(),
                 surface: &window.surface,
                 wid: make_wid(&window.surface),
                 frame: opt_mutex_lock.as_mut().map(|m| &mut **m),
+                decorations_action,
             });
+            *window.size.lock().unwrap() = size;
             if let Some(dpi) = window.new_dpi.take() {
                 window.current_dpi = dpi;
             }

src/platform_impl/linux/x11/event_processor.rs

@@ -1,7 +1,9 @@
-use std::{cell::RefCell, collections::HashMap, rc::Rc, slice};
+use std::{cell::RefCell, collections::HashMap, rc::Rc, slice, sync::Arc};
 
 use libc::{c_char, c_int, c_long, c_uint, c_ulong};
 
+use parking_lot::MutexGuard;
+
 use super::{
     events, ffi, get_xtarget, mkdid, mkwid, monitor, util, Device, DeviceId, DeviceInfo, Dnd,
     DndState, GenericEventCookie, ImeReceiver, ScrollOrientation, UnownedWindow, WindowId,
@@ -11,7 +13,7 @@ use super::{
 use util::modifiers::{ModifierKeyState, ModifierKeymap};
 
 use crate::{
-    dpi::{LogicalPosition, LogicalSize},
+    dpi::{PhysicalPosition, PhysicalSize},
     event::{
         DeviceEvent, ElementState, Event, KeyboardInput, ModifiersState, TouchPhase, WindowEvent,
     },
@@ -30,6 +32,8 @@ pub(super) struct EventProcessor<T: 'static> {
     // Number of touch events currently in progress
     pub(super) num_touch: u32,
     pub(super) first_touch: Option<u64>,
+    // Currently focused window belonging to this process
+    pub(super) active_window: Option<ffi::Window>,
 }
 
 impl<T: 'static> EventProcessor<T> {
@@ -45,7 +49,7 @@ impl<T: 'static> EventProcessor<T> {
 
     fn with_window<F, Ret>(&self, window_id: ffi::Window, callback: F) -> Option<Ret>
     where
-        F: Fn(&UnownedWindow) -> Ret,
+        F: Fn(&Arc<UnownedWindow>) -> Ret,
     {
         let mut deleted = false;
         let window_id = WindowId(window_id);
@@ -59,7 +63,7 @@ impl<T: 'static> EventProcessor<T> {
                 deleted = arc.is_none();
                 arc
             })
-            .map(|window| callback(&*window));
+            .map(|window| callback(&window));
         if deleted {
             // Garbage collection
             wt.windows.borrow_mut().remove(&window_id);
@@ -107,7 +111,7 @@ impl<T: 'static> EventProcessor<T> {
 
     pub(super) fn process_event<F>(&mut self, xev: &mut ffi::XEvent, mut callback: F)
     where
-        F: FnMut(Event<T>),
+        F: FnMut(Event<'_, T>),
     {
         let wt = get_xtarget(&self.target);
         // XFilterEvent tells us when an event has been discarded by the input method.
@@ -134,11 +138,12 @@ impl<T: 'static> EventProcessor<T> {
                         if let Some(modifiers) =
                             self.device_mod_state.update_state(&state, modifier)
                         {
-                            let device_id = mkdid(util::VIRTUAL_CORE_KEYBOARD);
-                            callback(Event::DeviceEvent {
-                                device_id,
-                                event: DeviceEvent::ModifiersChanged(modifiers),
-                            });
+                            if let Some(window_id) = self.active_window {
+                                callback(Event::WindowEvent {
+                                    window_id: mkwid(window_id),
+                                    event: WindowEvent::ModifiersChanged(modifiers),
+                                });
+                            }
                         }
                     }
                 }
@@ -321,16 +326,11 @@ impl<T: 'static> EventProcessor<T> {
             }
 
             ffi::ConfigureNotify => {
-                #[derive(Debug, Default)]
-                struct Events {
-                    resized: Option<WindowEvent>,
-                    moved: Option<WindowEvent>,
-                    dpi_changed: Option<WindowEvent>,
-                }
-
                 let xev: &ffi::XConfigureEvent = xev.as_ref();
                 let xwindow = xev.window;
-                let events = self.with_window(xwindow, |window| {
+                let window_id = mkwid(xwindow);
+
+                if let Some(window) = self.with_window(xwindow, Arc::clone) {
                     // So apparently...
                     // `XSendEvent` (synthetic `ConfigureNotify`) -> position relative to root
                     // `XConfigureNotify` (real `ConfigureNotify`) -> position relative to parent
@@ -344,7 +344,6 @@ impl<T: 'static> EventProcessor<T> {
                     let new_inner_size = (xev.width as u32, xev.height as u32);
                     let new_inner_position = (xev.x as i32, xev.y as i32);
 
-                    let mut monitor = window.current_monitor(); // This must be done *before* locking!
                     let mut shared_state_lock = window.shared_state.lock();
 
                     let (mut resized, moved) = {
@@ -374,8 +373,6 @@ impl<T: 'static> EventProcessor<T> {
                         (resized, moved)
                     };
 
-                    let mut events = Events::default();
-
                     let new_outer_position = if moved || shared_state_lock.position.is_none() {
                         // We need to convert client area position to window position.
                         let frame_extents = shared_state_lock
@@ -392,9 +389,13 @@ impl<T: 'static> EventProcessor<T> {
                             .inner_pos_to_outer(new_inner_position.0, new_inner_position.1);
                         shared_state_lock.position = Some(outer);
                         if moved {
-                            let logical_position =
-                                LogicalPosition::from_physical(outer, monitor.hidpi_factor);
-                            events.moved = Some(WindowEvent::Moved(logical_position));
+                            // Temporarily unlock shared state to prevent deadlock
+                            MutexGuard::unlocked(&mut shared_state_lock, || {
+                                callback(Event::WindowEvent {
+                                    window_id,
+                                    event: WindowEvent::Moved(outer.into()),
+                                });
+                            });
                         }
                         outer
                     } else {
@@ -406,36 +407,54 @@ impl<T: 'static> EventProcessor<T> {
                         // resizing by dragging across monitors *without* dropping the window.
                         let (width, height) = shared_state_lock
                             .dpi_adjusted
-                            .unwrap_or_else(|| (xev.width as f64, xev.height as f64));
+                            .unwrap_or_else(|| (xev.width as u32, xev.height as u32));
 
-                        let last_hidpi_factor = shared_state_lock.last_monitor.hidpi_factor;
-                        let new_hidpi_factor = {
+                        let last_scale_factor = shared_state_lock.last_monitor.scale_factor;
+                        let new_scale_factor = {
                             let window_rect = util::AaRect::new(new_outer_position, new_inner_size);
-                            let new_monitor = wt.xconn.get_monitor_for_window(Some(window_rect));
+                            let monitor = wt.xconn.get_monitor_for_window(Some(window_rect));
 
-                            if new_monitor.is_dummy() {
+                            if monitor.is_dummy() {
                                 // Avoid updating monitor using a dummy monitor handle
-                                last_hidpi_factor
+                                last_scale_factor
                             } else {
-                                monitor = new_monitor;
                                 shared_state_lock.last_monitor = monitor.clone();
-                                monitor.hidpi_factor
+                                monitor.scale_factor
                             }
                         };
-                        if last_hidpi_factor != new_hidpi_factor {
-                            events.dpi_changed =
-                                Some(WindowEvent::HiDpiFactorChanged(new_hidpi_factor));
-                            let (new_width, new_height, flusher) = window.adjust_for_dpi(
-                                last_hidpi_factor,
-                                new_hidpi_factor,
+                        if last_scale_factor != new_scale_factor {
+                            let (new_width, new_height) = window.adjust_for_dpi(
+                                last_scale_factor,
+                                new_scale_factor,
                                 width,
                                 height,
+                                &shared_state_lock,
                             );
-                            flusher.queue();
-                            shared_state_lock.dpi_adjusted = Some((new_width, new_height));
-                            // if the DPI factor changed, force a resize event to ensure the logical
-                            // size is computed with the right DPI factor
-                            resized = true;
+
+                            let old_inner_size = PhysicalSize::new(width, height);
+                            let mut new_inner_size = PhysicalSize::new(new_width, new_height);
+
+                            // Temporarily unlock shared state to prevent deadlock
+                            MutexGuard::unlocked(&mut shared_state_lock, || {
+                                callback(Event::WindowEvent {
+                                    window_id,
+                                    event: WindowEvent::ScaleFactorChanged {
+                                        scale_factor: new_scale_factor,
+                                        new_inner_size: &mut new_inner_size,
+                                    },
+                                });
+                            });
+
+                            if new_inner_size != old_inner_size {
+                                window.set_inner_size_physical(
+                                    new_inner_size.width,
+                                    new_inner_size.height,
+                                );
+                                shared_state_lock.dpi_adjusted = Some(new_inner_size.into());
+                                // if the DPI factor changed, force a resize event to ensure the logical
+                                // size is computed with the right DPI factor
+                                resized = true;
+                            }
                         }
                     }
 
@@ -444,44 +463,22 @@ impl<T: 'static> EventProcessor<T> {
                     // WMs constrain the window size, making the resize fail. This would cause an endless stream of
                     // XResizeWindow requests, making Xorg, the winit client, and the WM consume 100% of CPU.
                     if let Some(adjusted_size) = shared_state_lock.dpi_adjusted {
-                        let rounded_size = (
-                            adjusted_size.0.round() as u32,
-                            adjusted_size.1.round() as u32,
-                        );
-                        if new_inner_size == rounded_size || !util::wm_name_is_one_of(&["Xfwm4"]) {
+                        if new_inner_size == adjusted_size || !util::wm_name_is_one_of(&["Xfwm4"]) {
                             // When this finally happens, the event will not be synthetic.
                             shared_state_lock.dpi_adjusted = None;
                         } else {
-                            unsafe {
-                                (wt.xconn.xlib.XResizeWindow)(
-                                    wt.xconn.display,
-                                    xwindow,
-                                    rounded_size.0 as c_uint,
-                                    rounded_size.1 as c_uint,
-                                );
-                            }
+                            window.set_inner_size_physical(adjusted_size.0, adjusted_size.1);
                         }
                     }
 
                     if resized {
-                        let logical_size =
-                            LogicalSize::from_physical(new_inner_size, monitor.hidpi_factor);
-                        events.resized = Some(WindowEvent::Resized(logical_size));
-                    }
+                        // Drop the shared state lock to prevent deadlock
+                        drop(shared_state_lock);
 
-                    events
-                });
-
-                if let Some(events) = events {
-                    let window_id = mkwid(xwindow);
-                    if let Some(event) = events.dpi_changed {
-                        callback(Event::WindowEvent { window_id, event });
-                    }
-                    if let Some(event) = events.resized {
-                        callback(Event::WindowEvent { window_id, event });
-                    }
-                    if let Some(event) = events.moved {
-                        callback(Event::WindowEvent { window_id, event });
+                        callback(Event::WindowEvent {
+                            window_id,
+                            event: WindowEvent::Resized(new_inner_size.into()),
+                        });
                     }
                 }
             }
@@ -579,6 +576,7 @@ impl<T: 'static> EventProcessor<T> {
 
                     let modifiers = self.device_mod_state.modifiers();
 
+                    #[allow(deprecated)]
                     callback(Event::WindowEvent {
                         window_id,
                         event: WindowEvent::KeyboardInput {
@@ -728,24 +726,16 @@ impl<T: 'static> EventProcessor<T> {
                             util::maybe_change(&mut shared_state_lock.cursor_pos, new_cursor_pos)
                         });
                         if cursor_moved == Some(true) {
-                            let dpi_factor =
-                                self.with_window(xev.event, |window| window.hidpi_factor());
-                            if let Some(dpi_factor) = dpi_factor {
-                                let position = LogicalPosition::from_physical(
-                                    (xev.event_x as f64, xev.event_y as f64),
-                                    dpi_factor,
-                                );
-                                callback(Event::WindowEvent {
-                                    window_id,
-                                    event: CursorMoved {
-                                        device_id,
-                                        position,
-                                        modifiers,
-                                    },
-                                });
-                            } else {
-                                return;
-                            }
+                            let position = PhysicalPosition::new(xev.event_x, xev.event_y);
+
+                            callback(Event::WindowEvent {
+                                window_id,
+                                event: CursorMoved {
+                                    device_id,
+                                    position,
+                                    modifiers,
+                                },
+                            });
                         } else if cursor_moved.is_none() {
                             return;
                         }
@@ -836,18 +826,13 @@ impl<T: 'static> EventProcessor<T> {
                             }
                         }
 
-                        if let Some(dpi_factor) =
-                            self.with_window(xev.event, |window| window.hidpi_factor())
-                        {
+                        if self.window_exists(xev.event) {
                             callback(Event::WindowEvent {
                                 window_id,
                                 event: CursorEntered { device_id },
                             });
 
-                            let position = LogicalPosition::from_physical(
-                                (xev.event_x as f64, xev.event_y as f64),
-                                dpi_factor,
-                            );
+                            let position = PhysicalPosition::new(xev.event_x, xev.event_y);
 
                             // The mods field on this event isn't actually populated, so query the
                             // pointer device. In the future, we can likely remove this round-trip by
@@ -890,51 +875,58 @@ impl<T: 'static> EventProcessor<T> {
                     ffi::XI_FocusIn => {
                         let xev: &ffi::XIFocusInEvent = unsafe { &*(xev.data as *const _) };
 
-                        let dpi_factor =
-                            match self.with_window(xev.event, |window| window.hidpi_factor()) {
-                                Some(dpi_factor) => dpi_factor,
-                                None => return,
-                            };
-                        let window_id = mkwid(xev.event);
-
                         wt.ime
                             .borrow_mut()
                             .focus(xev.event)
                             .expect("Failed to focus input context");
 
-                        callback(Event::WindowEvent {
-                            window_id,
-                            event: Focused(true),
-                        });
-
                         let modifiers = ModifiersState::from_x11(&xev.mods);
 
-                        update_modifiers!(modifiers, None);
+                        self.device_mod_state.update_state(&modifiers, None);
 
-                        // The deviceid for this event is for a keyboard instead of a pointer,
-                        // so we have to do a little extra work.
-                        let pointer_id = self
-                            .devices
-                            .borrow()
-                            .get(&DeviceId(xev.deviceid))
-                            .map(|device| device.attachment)
-                            .unwrap_or(2);
+                        if self.active_window != Some(xev.event) {
+                            self.active_window = Some(xev.event);
 
-                        let position = LogicalPosition::from_physical(
-                            (xev.event_x as f64, xev.event_y as f64),
-                            dpi_factor,
-                        );
-                        callback(Event::WindowEvent {
-                            window_id,
-                            event: CursorMoved {
-                                device_id: mkdid(pointer_id),
-                                position,
-                                modifiers,
-                            },
-                        });
+                            let window_id = mkwid(xev.event);
+                            let position = PhysicalPosition::new(xev.event_x, xev.event_y);
 
-                        // Issue key press events for all pressed keys
-                        self.handle_pressed_keys(window_id, ElementState::Pressed, &mut callback);
+                            callback(Event::WindowEvent {
+                                window_id,
+                                event: Focused(true),
+                            });
+
+                            if !modifiers.is_empty() {
+                                callback(Event::WindowEvent {
+                                    window_id,
+                                    event: WindowEvent::ModifiersChanged(modifiers),
+                                });
+                            }
+
+                            // The deviceid for this event is for a keyboard instead of a pointer,
+                            // so we have to do a little extra work.
+                            let pointer_id = self
+                                .devices
+                                .borrow()
+                                .get(&DeviceId(xev.deviceid))
+                                .map(|device| device.attachment)
+                                .unwrap_or(2);
+
+                            callback(Event::WindowEvent {
+                                window_id,
+                                event: CursorMoved {
+                                    device_id: mkdid(pointer_id),
+                                    position,
+                                    modifiers,
+                                },
+                            });
+
+                            // Issue key press events for all pressed keys
+                            self.handle_pressed_keys(
+                                window_id,
+                                ElementState::Pressed,
+                                &mut callback,
+                            );
+                        }
                     }
                     ffi::XI_FocusOut => {
                         let xev: &ffi::XIFocusOutEvent = unsafe { &*(xev.data as *const _) };
@@ -946,15 +938,26 @@ impl<T: 'static> EventProcessor<T> {
                             .unfocus(xev.event)
                             .expect("Failed to unfocus input context");
 
-                        let window_id = mkwid(xev.event);
+                        if self.active_window.take() == Some(xev.event) {
+                            let window_id = mkwid(xev.event);
 
-                        // Issue key release events for all pressed keys
-                        self.handle_pressed_keys(window_id, ElementState::Released, &mut callback);
+                            // Issue key release events for all pressed keys
+                            self.handle_pressed_keys(
+                                window_id,
+                                ElementState::Released,
+                                &mut callback,
+                            );
 
-                        callback(Event::WindowEvent {
-                            window_id,
-                            event: Focused(false),
-                        })
+                            callback(Event::WindowEvent {
+                                window_id,
+                                event: WindowEvent::ModifiersChanged(ModifiersState::empty()),
+                            });
+
+                            callback(Event::WindowEvent {
+                                window_id,
+                                event: Focused(false),
+                            })
+                        }
                     }
 
                     ffi::XI_TouchBegin | ffi::XI_TouchUpdate | ffi::XI_TouchEnd => {
@@ -966,15 +969,11 @@ impl<T: 'static> EventProcessor<T> {
                             ffi::XI_TouchEnd => TouchPhase::Ended,
                             _ => unreachable!(),
                         };
-                        let dpi_factor =
-                            self.with_window(xev.event, |window| window.hidpi_factor());
-                        if let Some(dpi_factor) = dpi_factor {
+                        if self.window_exists(xev.event) {
                             let id = xev.detail as u64;
                             let modifiers = self.device_mod_state.modifiers();
-                            let location = LogicalPosition::from_physical(
-                                (xev.event_x as f64, xev.event_y as f64),
-                                dpi_factor,
-                            );
+                            let location =
+                                PhysicalPosition::new(xev.event_x as f64, xev.event_y as f64);
 
                             // Mouse cursor position changes when touch events are received.
                             // Only the first concurrently active touch ID moves the mouse cursor.
@@ -984,7 +983,7 @@ impl<T: 'static> EventProcessor<T> {
                                     window_id,
                                     event: WindowEvent::CursorMoved {
                                         device_id: mkdid(util::VIRTUAL_CORE_POINTER),
-                                        position: location,
+                                        position: location.cast(),
                                         modifiers,
                                     },
                                 });
@@ -1090,6 +1089,7 @@ impl<T: 'static> EventProcessor<T> {
                         let virtual_keycode = events::keysym_to_element(keysym as c_uint);
                         let modifiers = self.device_mod_state.modifiers();
 
+                        #[allow(deprecated)]
                         callback(Event::DeviceEvent {
                             device_id,
                             event: DeviceEvent::Key(KeyboardInput {
@@ -1112,10 +1112,12 @@ impl<T: 'static> EventProcessor<T> {
                             let new_modifiers = self.device_mod_state.modifiers();
 
                             if modifiers != new_modifiers {
-                                callback(Event::DeviceEvent {
-                                    device_id,
-                                    event: DeviceEvent::ModifiersChanged(new_modifiers),
-                                });
+                                if let Some(window_id) = self.active_window {
+                                    callback(Event::WindowEvent {
+                                        window_id: mkwid(window_id),
+                                        event: WindowEvent::ModifiersChanged(new_modifiers),
+                                    });
+                                }
                             }
                         }
                     }
@@ -1157,27 +1159,48 @@ impl<T: 'static> EventProcessor<T> {
                                 .iter()
                                 .find(|prev_monitor| prev_monitor.name == new_monitor.name)
                                 .map(|prev_monitor| {
-                                    if new_monitor.hidpi_factor != prev_monitor.hidpi_factor {
+                                    if new_monitor.scale_factor != prev_monitor.scale_factor {
                                         for (window_id, window) in wt.windows.borrow().iter() {
                                             if let Some(window) = window.upgrade() {
                                                 // Check if the window is on this monitor
                                                 let monitor = window.current_monitor();
                                                 if monitor.name == new_monitor.name {
-                                                    callback(Event::WindowEvent {
-                                                        window_id: mkwid(window_id.0),
-                                                        event: WindowEvent::HiDpiFactorChanged(
-                                                            new_monitor.hidpi_factor,
-                                                        ),
-                                                    });
                                                     let (width, height) =
                                                         window.inner_size_physical();
-                                                    let (_, _, flusher) = window.adjust_for_dpi(
-                                                        prev_monitor.hidpi_factor,
-                                                        new_monitor.hidpi_factor,
-                                                        width as f64,
-                                                        height as f64,
+                                                    let (new_width, new_height) = window
+                                                        .adjust_for_dpi(
+                                                            prev_monitor.scale_factor,
+                                                            new_monitor.scale_factor,
+                                                            width,
+                                                            height,
+                                                            &*window.shared_state.lock(),
+                                                        );
+
+                                                    let window_id = crate::window::WindowId(
+                                                        crate::platform_impl::platform::WindowId::X(
+                                                            *window_id,
+                                                        ),
                                                     );
-                                                    flusher.queue();
+                                                    let old_inner_size =
+                                                        PhysicalSize::new(width, height);
+                                                    let mut new_inner_size =
+                                                        PhysicalSize::new(new_width, new_height);
+
+                                                    callback(Event::WindowEvent {
+                                                        window_id,
+                                                        event: WindowEvent::ScaleFactorChanged {
+                                                            scale_factor: new_monitor.scale_factor,
+                                                            new_inner_size: &mut new_inner_size,
+                                                        },
+                                                    });
+
+                                                    if new_inner_size != old_inner_size {
+                                                        let (new_width, new_height) =
+                                                            new_inner_size.into();
+                                                        window.set_inner_size_physical(
+                                                            new_width, new_height,
+                                                        );
+                                                    }
                                                 }
                                             }
                                         }
@@ -1203,7 +1226,7 @@ impl<T: 'static> EventProcessor<T> {
         state: ElementState,
         callback: &mut F,
     ) where
-        F: FnMut(Event<T>),
+        F: FnMut(Event<'_, T>),
     {
         let wt = get_xtarget(&self.target);
 
@@ -1222,6 +1245,7 @@ impl<T: 'static> EventProcessor<T> {
             let keysym = wt.xconn.keycode_to_keysym(keycode);
             let virtual_keycode = events::keysym_to_element(keysym as c_uint);
 
+            #[allow(deprecated)]
             callback(Event::WindowEvent {
                 window_id,
                 event: WindowEvent::KeyboardInput {

src/platform_impl/linux/x11/ime/input_method.rs

@@ -21,7 +21,8 @@ unsafe fn open_im(xconn: &Arc<XConnection>, locale_modifiers: &CStr) -> Option<f
     // XSetLocaleModifiers returns...
     // * The current locale modifiers if it's given a NULL pointer.
     // * The new locale modifiers if we succeeded in setting them.
-    // * NULL if the locale modifiers string is malformed.
+    // * NULL if the locale modifiers string is malformed or if the
+    //   current locale is not supported by Xlib.
     (xconn.xlib.XSetLocaleModifiers)(locale_modifiers.as_ptr());
 
     let im = (xconn.xlib.XOpenIM)(

src/platform_impl/linux/x11/mod.rs

@@ -24,11 +24,12 @@ pub use self::{
 
 use std::{
     cell::RefCell,
-    collections::{HashMap, HashSet, VecDeque},
+    collections::{HashMap, HashSet},
     ffi::CStr,
     mem::{self, MaybeUninit},
     ops::Deref,
     os::raw::*,
+    ptr,
     rc::Rc,
     slice,
     sync::{mpsc, Arc, Mutex, Weak},
@@ -37,6 +38,10 @@ use std::{
 
 use libc::{self, setlocale, LC_CTYPE};
 
+use mio::{unix::EventedFd, Events, Poll, PollOpt, Ready, Token};
+
+use mio_extras::channel::{channel, Receiver, SendError, Sender};
+
 use self::{
     dnd::{Dnd, DndState},
     event_processor::EventProcessor,
@@ -51,6 +56,9 @@ use crate::{
     window::WindowAttributes,
 };
 
+const X_TOKEN: Token = Token(0);
+const USER_TOKEN: Token = Token(1);
+
 pub struct EventLoopWindowTarget<T> {
     xconn: Arc<XConnection>,
     wm_delete_window: ffi::Atom,
@@ -64,18 +72,15 @@ pub struct EventLoopWindowTarget<T> {
 }
 
 pub struct EventLoop<T: 'static> {
-    inner_loop: ::calloop::EventLoop<()>,
-    _x11_source: ::calloop::Source<::calloop::generic::Generic<::calloop::generic::EventedRawFd>>,
-    _user_source: ::calloop::Source<::calloop::channel::Channel<T>>,
-    pending_user_events: Rc<RefCell<VecDeque<T>>>,
-    event_processor: Rc<RefCell<EventProcessor<T>>>,
-    user_sender: ::calloop::channel::Sender<T>,
-    pending_events: Rc<RefCell<VecDeque<Event<T>>>>,
-    pub(crate) target: Rc<RootELW<T>>,
+    poll: Poll,
+    event_processor: EventProcessor<T>,
+    user_channel: Receiver<T>,
+    user_sender: Sender<T>,
+    target: Rc<RootELW<T>>,
 }
 
 pub struct EventLoopProxy<T: 'static> {
-    user_sender: ::calloop::channel::Sender<T>,
+    user_sender: Sender<T>,
 }
 
 impl<T: 'static> Clone for EventLoopProxy<T> {
@@ -101,7 +106,25 @@ impl<T: 'static> EventLoop<T> {
         // Input methods will open successfully without setting the locale, but it won't be
         // possible to actually commit pre-edit sequences.
         unsafe {
+            // Remember default locale to restore it if target locale is unsupported
+            // by Xlib
+            let default_locale = setlocale(LC_CTYPE, ptr::null());
             setlocale(LC_CTYPE, b"\0".as_ptr() as *const _);
+
+            // Check if set locale is supported by Xlib.
+            // If not, calls to some Xlib functions like `XSetLocaleModifiers`
+            // will fail.
+            let locale_supported = (xconn.xlib.XSupportsLocale)() == 1;
+            if !locale_supported {
+                let unsupported_locale = setlocale(LC_CTYPE, ptr::null());
+                warn!(
+                    "Unsupported locale \"{}\". Restoring default locale \"{}\".",
+                    CStr::from_ptr(unsupported_locale).to_string_lossy(),
+                    CStr::from_ptr(default_locale).to_string_lossy()
+                );
+                // Restore default locale
+                setlocale(LC_CTYPE, default_locale);
+            }
         }
         let ime = RefCell::new({
             let result = Ime::new(Arc::clone(&xconn));
@@ -171,28 +194,27 @@ impl<T: 'static> EventLoop<T> {
             _marker: ::std::marker::PhantomData,
         });
 
-        // A calloop event loop to drive us
-        let inner_loop = ::calloop::EventLoop::new().unwrap();
+        let poll = Poll::new().unwrap();
 
-        // Handle user events
-        let pending_user_events = Rc::new(RefCell::new(VecDeque::new()));
-        let pending_user_events2 = pending_user_events.clone();
+        let (user_sender, user_channel) = channel();
 
-        let (user_sender, user_channel) = ::calloop::channel::channel();
+        poll.register(
+            &EventedFd(&get_xtarget(&target).xconn.x11_fd),
+            X_TOKEN,
+            Ready::readable(),
+            PollOpt::level(),
+        )
+        .unwrap();
 
-        let _user_source = inner_loop
-            .handle()
-            .insert_source(user_channel, move |evt, &mut ()| {
-                if let ::calloop::channel::Event::Msg(msg) = evt {
-                    pending_user_events2.borrow_mut().push_back(msg);
-                }
-            })
-            .unwrap();
+        poll.register(
+            &user_channel,
+            USER_TOKEN,
+            Ready::readable(),
+            PollOpt::level(),
+        )
+        .unwrap();
 
-        // Handle X11 events
-        let pending_events: Rc<RefCell<VecDeque<_>>> = Default::default();
-
-        let processor = EventProcessor {
+        let event_processor = EventProcessor {
             target: target.clone(),
             dnd,
             devices: Default::default(),
@@ -203,6 +225,7 @@ impl<T: 'static> EventLoop<T> {
             device_mod_state: Default::default(),
             num_touch: 0,
             first_touch: None,
+            active_window: None,
         };
 
         // Register for device hotplug events
@@ -212,38 +235,12 @@ impl<T: 'static> EventLoop<T> {
             .select_xinput_events(root, ffi::XIAllDevices, ffi::XI_HierarchyChangedMask)
             .queue();
 
-        processor.init_device(ffi::XIAllDevices);
-
-        let processor = Rc::new(RefCell::new(processor));
-        let event_processor = processor.clone();
-
-        // Setup the X11 event source
-        let mut x11_events =
-            ::calloop::generic::Generic::from_raw_fd(get_xtarget(&target).xconn.x11_fd);
-        x11_events.set_interest(::calloop::mio::Ready::readable());
-        let _x11_source = inner_loop
-            .handle()
-            .insert_source(x11_events, {
-                let pending_events = pending_events.clone();
-                move |evt, &mut ()| {
-                    if evt.readiness.is_readable() {
-                        let mut processor = processor.borrow_mut();
-                        let mut pending_events = pending_events.borrow_mut();
-                        let mut pending_redraws = pending_redraws.lock().unwrap();
-
-                        drain_events(&mut processor, &mut pending_events, &mut pending_redraws);
-                    }
-                }
-            })
-            .unwrap();
+        event_processor.init_device(ffi::XIAllDevices);
 
         let result = EventLoop {
-            inner_loop,
-            pending_events,
-            _x11_source,
-            _user_source,
+            poll,
+            user_channel,
             user_sender,
-            pending_user_events,
             event_processor,
             target,
         };
@@ -261,12 +258,16 @@ impl<T: 'static> EventLoop<T> {
         &self.target
     }
 
+    pub(crate) fn x_connection(&self) -> &Arc<XConnection> {
+        get_xtarget(&self.target).x_connection()
+    }
+
     pub fn run_return<F>(&mut self, mut callback: F)
     where
-        F: FnMut(Event<T>, &RootELW<T>, &mut ControlFlow),
+        F: FnMut(Event<'_, T>, &RootELW<T>, &mut ControlFlow),
     {
         let mut control_flow = ControlFlow::default();
-        let wt = get_xtarget(&self.target);
+        let mut events = Events::with_capacity(8);
 
         callback(
             crate::event::Event::NewEvents(crate::event::StartCause::Init),
@@ -275,22 +276,16 @@ impl<T: 'static> EventLoop<T> {
         );
 
         loop {
-            self.drain_events();
+            // Process all pending events
+            self.drain_events(&mut callback, &mut control_flow);
 
-            // Empty the event buffer
-            {
-                let mut guard = self.pending_events.borrow_mut();
-                for evt in guard.drain(..) {
-                    sticky_exit_callback(evt, &self.target, &mut control_flow, &mut callback);
-                }
-            }
+            let wt = get_xtarget(&self.target);
 
             // Empty the user event buffer
             {
-                let mut guard = self.pending_user_events.borrow_mut();
-                for evt in guard.drain(..) {
+                while let Ok(event) = self.user_channel.try_recv() {
                     sticky_exit_callback(
-                        crate::event::Event::UserEvent(evt),
+                        crate::event::Event::UserEvent(event),
                         &self.target,
                         &mut control_flow,
                         &mut callback,
@@ -331,7 +326,7 @@ impl<T: 'static> EventLoop<T> {
             }
 
             let start = Instant::now();
-            let (mut cause, deadline, mut timeout);
+            let (mut cause, deadline, timeout);
 
             match control_flow {
                 ControlFlow::Exit => break,
@@ -362,26 +357,39 @@ impl<T: 'static> EventLoop<T> {
                 }
             }
 
-            if self.events_waiting() {
-                timeout = Some(Duration::from_millis(0));
-            }
+            if self.event_processor.poll() {
+                // If the XConnection already contains buffered events, we don't
+                // need to wait for data on the socket.
+                // However, we still need to check for user events.
+                self.poll
+                    .poll(&mut events, Some(Duration::from_millis(0)))
+                    .unwrap();
+                events.clear();
 
-            self.inner_loop.dispatch(timeout, &mut ()).unwrap();
+                callback(
+                    crate::event::Event::NewEvents(cause),
+                    &self.target,
+                    &mut control_flow,
+                );
+            } else {
+                self.poll.poll(&mut events, timeout).unwrap();
+                events.clear();
 
-            if let Some(deadline) = deadline {
-                if deadline > Instant::now() {
+                let wait_cancelled = deadline.map_or(false, |deadline| Instant::now() < deadline);
+
+                if wait_cancelled {
                     cause = StartCause::WaitCancelled {
                         start,
-                        requested_resume: Some(deadline),
+                        requested_resume: deadline,
                     };
                 }
-            }
 
-            callback(
-                crate::event::Event::NewEvents(cause),
-                &self.target,
-                &mut control_flow,
-            );
+                callback(
+                    crate::event::Event::NewEvents(cause),
+                    &self.target,
+                    &mut control_flow,
+                );
+            }
         }
 
         callback(
@@ -393,44 +401,41 @@ impl<T: 'static> EventLoop<T> {
 
     pub fn run<F>(mut self, callback: F) -> !
     where
-        F: 'static + FnMut(Event<T>, &RootELW<T>, &mut ControlFlow),
+        F: 'static + FnMut(Event<'_, T>, &RootELW<T>, &mut ControlFlow),
     {
         self.run_return(callback);
         ::std::process::exit(0);
     }
 
-    fn drain_events(&self) {
-        let mut processor = self.event_processor.borrow_mut();
-        let mut pending_events = self.pending_events.borrow_mut();
+    fn drain_events<F>(&mut self, callback: &mut F, control_flow: &mut ControlFlow)
+    where
+        F: FnMut(Event<'_, T>, &RootELW<T>, &mut ControlFlow),
+    {
+        let target = &self.target;
+        let mut xev = MaybeUninit::uninit();
+
         let wt = get_xtarget(&self.target);
-        let mut pending_redraws = wt.pending_redraws.lock().unwrap();
 
-        drain_events(&mut processor, &mut pending_events, &mut pending_redraws);
-    }
-
-    fn events_waiting(&self) -> bool {
-        !self.pending_events.borrow().is_empty() || self.event_processor.borrow().poll()
-    }
-}
-
-fn drain_events<T: 'static>(
-    processor: &mut EventProcessor<T>,
-    pending_events: &mut VecDeque<Event<T>>,
-    pending_redraws: &mut HashSet<WindowId>,
-) {
-    let mut callback = |event| {
-        if let Event::RedrawRequested(crate::window::WindowId(super::WindowId::X(wid))) = event {
-            pending_redraws.insert(wid);
-        } else {
-            pending_events.push_back(event);
+        while unsafe { self.event_processor.poll_one_event(xev.as_mut_ptr()) } {
+            let mut xev = unsafe { xev.assume_init() };
+            self.event_processor.process_event(&mut xev, |event| {
+                sticky_exit_callback(
+                    event,
+                    target,
+                    control_flow,
+                    &mut |event, window_target, control_flow| {
+                        if let Event::RedrawRequested(crate::window::WindowId(
+                            super::WindowId::X(wid),
+                        )) = event
+                        {
+                            wt.pending_redraws.lock().unwrap().insert(wid);
+                        } else {
+                            callback(event, window_target, control_flow);
+                        }
+                    },
+                );
+            });
         }
-    };
-
-    // process all pending events
-    let mut xev = MaybeUninit::uninit();
-    while unsafe { processor.poll_one_event(xev.as_mut_ptr()) } {
-        let mut xev = unsafe { xev.assume_init() };
-        processor.process_event(&mut xev, &mut callback);
     }
 }
 
@@ -452,7 +457,7 @@ impl<T> EventLoopWindowTarget<T> {
 impl<T: 'static> EventLoopProxy<T> {
     pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed<T>> {
         self.user_sender.send(event).map_err(|e| {
-            EventLoopClosed(if let ::calloop::channel::SendError::Disconnected(x) = e {
+            EventLoopClosed(if let SendError::Disconnected(x) = e {
                 x
             } else {
                 unreachable!()
@@ -504,21 +509,9 @@ impl<'a> Deref for DeviceInfo<'a> {
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct WindowId(ffi::Window);
 
-impl WindowId {
-    pub unsafe fn dummy() -> Self {
-        WindowId(0)
-    }
-}
-
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct DeviceId(c_int);
 
-impl DeviceId {
-    pub unsafe fn dummy() -> Self {
-        DeviceId(0)
-    }
-}
-
 pub struct Window(Arc<UnownedWindow>);
 
 impl Deref for Window {

src/platform_impl/linux/x11/monitor.rs

@@ -38,7 +38,7 @@ pub struct VideoMode {
 
 impl VideoMode {
     #[inline]
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         self.size.into()
     }
 
@@ -73,7 +73,7 @@ pub struct MonitorHandle {
     /// If the monitor is the primary one
     primary: bool,
     /// The DPI scale factor
-    pub(crate) hidpi_factor: f64,
+    pub(crate) scale_factor: f64,
     /// Used to determine which windows are on this monitor
     pub(crate) rect: util::AaRect,
     /// Supported video modes on this monitor
@@ -114,14 +114,14 @@ impl MonitorHandle {
         crtc: *mut XRRCrtcInfo,
         primary: bool,
     ) -> Option<Self> {
-        let (name, hidpi_factor, video_modes) = unsafe { xconn.get_output_info(resources, crtc)? };
+        let (name, scale_factor, video_modes) = unsafe { xconn.get_output_info(resources, crtc)? };
         let dimensions = unsafe { ((*crtc).width as u32, (*crtc).height as u32) };
         let position = unsafe { ((*crtc).x as i32, (*crtc).y as i32) };
         let rect = util::AaRect::new(position, dimensions);
         Some(MonitorHandle {
             id,
             name,
-            hidpi_factor,
+            scale_factor,
             dimensions,
             position,
             primary,
@@ -134,7 +134,7 @@ impl MonitorHandle {
         MonitorHandle {
             id: 0,
             name: "<dummy monitor>".into(),
-            hidpi_factor: 1.0,
+            scale_factor: 1.0,
             dimensions: (1, 1),
             position: (0, 0),
             primary: true,
@@ -157,17 +157,17 @@ impl MonitorHandle {
         self.id as u32
     }
 
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         self.dimensions.into()
     }
 
-    pub fn position(&self) -> PhysicalPosition {
+    pub fn position(&self) -> PhysicalPosition<i32> {
         self.position.into()
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f64 {
-        self.hidpi_factor
+    pub fn scale_factor(&self) -> f64 {
+        self.scale_factor
     }
 
     #[inline]

src/platform_impl/linux/x11/util/client_msg.rs

@@ -43,62 +43,4 @@ impl XConnection {
         };
         self.send_event(target_window, event_mask, event)
     }
-
-    // Prepare yourself for the ultimate in unsafety!
-    // You should favor `send_client_msg` whenever possible, but some protocols (i.e. startup notification) require you
-    // to send more than one message worth of data.
-    pub fn send_client_msg_multi<T: Formattable>(
-        &self,
-        window: c_ulong, // The window this is "about"; not necessarily this window
-        target_window: c_ulong, // The window we're sending to
-        message_type: ffi::Atom,
-        event_mask: Option<c_long>,
-        data: &[T],
-    ) -> Flusher<'_> {
-        let format = T::FORMAT;
-        let size_of_t = mem::size_of::<T>();
-        debug_assert_eq!(size_of_t, format.get_actual_size());
-        let mut event = ffi::XClientMessageEvent {
-            type_: ffi::ClientMessage,
-            display: self.display,
-            window,
-            message_type,
-            format: format as c_int,
-            data: ffi::ClientMessageData::new(),
-            // These fields are ignored by `XSendEvent`
-            serial: 0,
-            send_event: 0,
-        };
-
-        let t_per_payload = format.get_payload_size() / size_of_t;
-        assert!(t_per_payload > 0);
-        let payload_count = data.len() / t_per_payload;
-        let payload_remainder = data.len() % t_per_payload;
-        let payload_ptr = data.as_ptr() as *const ClientMsgPayload;
-
-        let mut payload_index = 0;
-        while payload_index < payload_count {
-            let payload = unsafe { payload_ptr.offset(payload_index as isize) };
-            payload_index += 1;
-            event.data = unsafe { mem::transmute(*payload) };
-            self.send_event(target_window, event_mask, &event).queue();
-        }
-
-        if payload_remainder > 0 {
-            let mut payload: ClientMsgPayload = [0; 5];
-            let t_payload = payload.as_mut_ptr() as *mut T;
-            let invalid_payload = unsafe { payload_ptr.offset(payload_index as isize) };
-            let invalid_t_payload = invalid_payload as *const T;
-            let mut t_index = 0;
-            while t_index < payload_remainder {
-                let valid_t = unsafe { invalid_t_payload.offset(t_index as isize) };
-                unsafe { (*t_payload.offset(t_index as isize)) = (*valid_t).clone() };
-                t_index += 1;
-            }
-            event.data = unsafe { mem::transmute(payload) };
-            self.send_event(target_window, event_mask, &event).queue();
-        }
-
-        Flusher::new(self)
-    }
 }

src/platform_impl/linux/x11/util/format.rs

@@ -21,10 +21,6 @@ impl Format {
         }
     }
 
-    pub fn is_same_size_as<T>(&self) -> bool {
-        mem::size_of::<T>() == self.get_actual_size()
-    }
-
     pub fn get_actual_size(&self) -> usize {
         match self {
             &Format::Char => mem::size_of::<c_char>(),
@@ -32,15 +28,6 @@ impl Format {
             &Format::Long => mem::size_of::<c_long>(),
         }
     }
-
-    pub fn get_payload_size(&self) -> usize {
-        match self {
-            // Due to the wonders of X11, half the space goes unused if you're not using longs (on 64-bit).
-            &Format::Char => mem::size_of::<c_char>() * 20,
-            &Format::Short => mem::size_of::<c_short>() * 10,
-            &Format::Long => mem::size_of::<c_long>() * 5,
-        }
-    }
 }
 
 pub trait Formattable: Debug + Clone + Copy + PartialEq + PartialOrd {

src/platform_impl/linux/x11/util/geometry.rs

@@ -1,7 +1,6 @@
 use std::cmp;
 
 use super::*;
-use crate::dpi::{LogicalPosition, LogicalSize};
 
 // Friendly neighborhood axis-aligned rectangle
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -89,16 +88,6 @@ impl FrameExtents {
     pub fn from_border(border: c_ulong) -> Self {
         Self::new(border, border, border, border)
     }
-
-    pub fn as_logical(&self, factor: f64) -> LogicalFrameExtents {
-        let logicalize = |value: c_ulong| value as f64 / factor;
-        LogicalFrameExtents {
-            left: logicalize(self.left),
-            right: logicalize(self.right),
-            top: logicalize(self.top),
-            bottom: logicalize(self.bottom),
-        }
-    }
 }
 
 #[derive(Debug, Clone)]
@@ -135,20 +124,6 @@ impl FrameExtentsHeuristic {
         }
     }
 
-    pub fn inner_pos_to_outer_logical(
-        &self,
-        mut logical: LogicalPosition,
-        factor: f64,
-    ) -> LogicalPosition {
-        use self::FrameExtentsHeuristicPath::*;
-        if self.heuristic_path != UnsupportedBordered {
-            let frame_extents = self.frame_extents.as_logical(factor);
-            logical.x -= frame_extents.left;
-            logical.y -= frame_extents.top;
-        }
-        logical
-    }
-
     pub fn inner_size_to_outer(&self, width: u32, height: u32) -> (u32, u32) {
         (
             width.saturating_add(
@@ -163,17 +138,6 @@ impl FrameExtentsHeuristic {
             ),
         )
     }
-
-    pub fn inner_size_to_outer_logical(
-        &self,
-        mut logical: LogicalSize,
-        factor: f64,
-    ) -> LogicalSize {
-        let frame_extents = self.frame_extents.as_logical(factor);
-        logical.width += frame_extents.left + frame_extents.right;
-        logical.height += frame_extents.top + frame_extents.bottom;
-        logical
-    }
 }
 
 impl XConnection {

src/platform_impl/linux/x11/util/hint.rs

@@ -4,6 +4,7 @@ use std::sync::Arc;
 use super::*;
 
 #[derive(Debug)]
+#[allow(dead_code)]
 pub enum StateOperation {
     Remove = 0, // _NET_WM_STATE_REMOVE
     Add = 1,    // _NET_WM_STATE_ADD
@@ -189,22 +190,6 @@ impl<'a> NormalHints<'a> {
         }
     }
 
-    pub fn has_flag(&self, flag: c_long) -> bool {
-        has_flag(self.size_hints.flags, flag)
-    }
-
-    fn getter(&self, flag: c_long, field1: &c_int, field2: &c_int) -> Option<(u32, u32)> {
-        if self.has_flag(flag) {
-            Some((*field1 as _, *field2 as _))
-        } else {
-            None
-        }
-    }
-
-    pub fn get_size(&self) -> Option<(u32, u32)> {
-        self.getter(ffi::PSize, &self.size_hints.width, &self.size_hints.height)
-    }
-
     // WARNING: This hint is obsolete
     pub fn set_size(&mut self, size: Option<(u32, u32)>) {
         if let Some((width, height)) = size {
@@ -216,14 +201,6 @@ impl<'a> NormalHints<'a> {
         }
     }
 
-    pub fn get_max_size(&self) -> Option<(u32, u32)> {
-        self.getter(
-            ffi::PMaxSize,
-            &self.size_hints.max_width,
-            &self.size_hints.max_height,
-        )
-    }
-
     pub fn set_max_size(&mut self, max_size: Option<(u32, u32)>) {
         if let Some((max_width, max_height)) = max_size {
             self.size_hints.flags |= ffi::PMaxSize;
@@ -234,14 +211,6 @@ impl<'a> NormalHints<'a> {
         }
     }
 
-    pub fn get_min_size(&self) -> Option<(u32, u32)> {
-        self.getter(
-            ffi::PMinSize,
-            &self.size_hints.min_width,
-            &self.size_hints.min_height,
-        )
-    }
-
     pub fn set_min_size(&mut self, min_size: Option<(u32, u32)>) {
         if let Some((min_width, min_height)) = min_size {
             self.size_hints.flags |= ffi::PMinSize;
@@ -252,14 +221,6 @@ impl<'a> NormalHints<'a> {
         }
     }
 
-    pub fn get_resize_increments(&self) -> Option<(u32, u32)> {
-        self.getter(
-            ffi::PResizeInc,
-            &self.size_hints.width_inc,
-            &self.size_hints.height_inc,
-        )
-    }
-
     pub fn set_resize_increments(&mut self, resize_increments: Option<(u32, u32)>) {
         if let Some((width_inc, height_inc)) = resize_increments {
             self.size_hints.flags |= ffi::PResizeInc;
@@ -270,14 +231,6 @@ impl<'a> NormalHints<'a> {
         }
     }
 
-    pub fn get_base_size(&self) -> Option<(u32, u32)> {
-        self.getter(
-            ffi::PBaseSize,
-            &self.size_hints.base_width,
-            &self.size_hints.base_height,
-        )
-    }
-
     pub fn set_base_size(&mut self, base_size: Option<(u32, u32)>) {
         if let Some((base_width, base_height)) = base_size {
             self.size_hints.flags |= ffi::PBaseSize;

src/platform_impl/linux/x11/util/icon.rs

@@ -1,5 +1,5 @@
 use super::*;
-use crate::window::{Icon, Pixel, PIXEL_SIZE};
+use crate::icon::{Icon, Pixel, PIXEL_SIZE};
 
 impl Pixel {
     pub fn to_packed_argb(&self) -> Cardinal {
@@ -18,13 +18,14 @@ impl Pixel {
 
 impl Icon {
     pub(crate) fn to_cardinals(&self) -> Vec<Cardinal> {
-        assert_eq!(self.rgba.len() % PIXEL_SIZE, 0);
-        let pixel_count = self.rgba.len() / PIXEL_SIZE;
-        assert_eq!(pixel_count, (self.width * self.height) as usize);
+        let rgba_icon = &self.inner;
+        assert_eq!(rgba_icon.rgba.len() % PIXEL_SIZE, 0);
+        let pixel_count = rgba_icon.rgba.len() / PIXEL_SIZE;
+        assert_eq!(pixel_count, (rgba_icon.width * rgba_icon.height) as usize);
         let mut data = Vec::with_capacity(pixel_count);
-        data.push(self.width as Cardinal);
-        data.push(self.height as Cardinal);
-        let pixels = self.rgba.as_ptr() as *const Pixel;
+        data.push(rgba_icon.width as Cardinal);
+        data.push(rgba_icon.height as Cardinal);
+        let pixels = rgba_icon.rgba.as_ptr() as *const Pixel;
         for pixel_index in 0..pixel_count {
             let pixel = unsafe { &*pixels.offset(pixel_index as isize) };
             data.push(pixel.to_packed_argb());

src/platform_impl/linux/x11/util/input.rs

@@ -18,9 +18,9 @@ impl ModifiersState {
 
     pub(crate) fn from_x11_mask(mask: c_uint) -> Self {
         let mut m = ModifiersState::empty();
-        m.set(ModifiersState::SHIFT, mask & ffi::Mod1Mask != 0);
-        m.set(ModifiersState::CTRL, mask & ffi::ShiftMask != 0);
-        m.set(ModifiersState::ALT, mask & ffi::ControlMask != 0);
+        m.set(ModifiersState::ALT, mask & ffi::Mod1Mask != 0);
+        m.set(ModifiersState::SHIFT, mask & ffi::ShiftMask != 0);
+        m.set(ModifiersState::CTRL, mask & ffi::ControlMask != 0);
         m.set(ModifiersState::LOGO, mask & ffi::Mod4Mask != 0);
         m
     }

src/platform_impl/linux/x11/util/mod.rs

@@ -23,18 +23,12 @@ pub use self::{
 
 use std::{
     mem::{self, MaybeUninit},
-    ops::BitAnd,
     os::raw::*,
     ptr,
 };
 
 use super::{ffi, XConnection, XError};
 
-pub fn reinterpret<'a, A, B>(a: &'a A) -> &'a B {
-    let b_ptr = a as *const _ as *const B;
-    unsafe { &*b_ptr }
-}
-
 pub fn maybe_change<T: PartialEq>(field: &mut Option<T>, value: T) -> bool {
     let wrapped = Some(value);
     if *field != wrapped {
@@ -45,13 +39,6 @@ pub fn maybe_change<T: PartialEq>(field: &mut Option<T>, value: T) -> bool {
     }
 }
 
-pub fn has_flag<T>(bitset: T, flag: T) -> bool
-where
-    T: Copy + PartialEq + BitAnd<T, Output = T>,
-{
-    bitset & flag == flag
-}
-
 #[must_use = "This request was made asynchronously, and is still in the output buffer. You must explicitly choose to either `.flush()` (empty the output buffer, sending the request now) or `.queue()` (wait to send the request, allowing you to continue to add more requests without additional round-trips). For more information, see the documentation for `util::flush_requests`."]
 pub struct Flusher<'a> {
     xconn: &'a XConnection,

src/platform_impl/linux/x11/util/randr.rs

@@ -4,7 +4,7 @@ use super::{
     ffi::{CurrentTime, RRCrtc, RRMode, Success, XRRCrtcInfo, XRRScreenResources},
     *,
 };
-use crate::{dpi::validate_hidpi_factor, platform_impl::platform::x11::VideoMode};
+use crate::{dpi::validate_scale_factor, platform_impl::platform::x11::VideoMode};
 
 /// Represents values of `WINIT_HIDPI_FACTOR`.
 pub enum EnvVarDPI {
@@ -26,7 +26,7 @@ pub fn calc_dpi_factor(
     let ppmm = ((width_px as f64 * height_px as f64) / (width_mm as f64 * height_mm as f64)).sqrt();
     // Quantize 1/12 step size
     let dpi_factor = ((ppmm * (12.0 * 25.4 / 96.0)).round() / 12.0).max(1.0);
-    assert!(validate_hidpi_factor(dpi_factor));
+    assert!(validate_scale_factor(dpi_factor));
     dpi_factor
 }
 
@@ -100,8 +100,14 @@ impl XConnection {
             (*output_info).nameLen as usize,
         );
         let name = String::from_utf8_lossy(name_slice).into();
-        // Override DPI if `WINIT_HIDPI_FACTOR` variable is set
-        let dpi_env = env::var("WINIT_HIDPI_FACTOR").ok().map_or_else(
+        // Override DPI if `WINIT_X11_SCALE_FACTOR` variable is set
+        let deprecated_dpi_override = env::var("WINIT_HIDPI_FACTOR").ok();
+        if deprecated_dpi_override.is_some() {
+            warn!(
+	            "The WINIT_HIDPI_FACTOR environment variable is deprecated; use WINIT_X11_SCALE_FACTOR"
+	        )
+        }
+        let dpi_env = env::var("WINIT_X11_SCALE_FACTOR").ok().map_or_else(
             || EnvVarDPI::NotSet,
             |var| {
                 if var.to_lowercase() == "randr" {
@@ -112,14 +118,14 @@ impl XConnection {
                     EnvVarDPI::NotSet
                 } else {
                     panic!(
-                        "`WINIT_HIDPI_FACTOR` invalid; DPI factors must be either normal floats greater than 0, or `randr`. Got `{}`",
+                        "`WINIT_X11_SCALE_FACTOR` invalid; DPI factors must be either normal floats greater than 0, or `randr`. Got `{}`",
                         var
                     );
                 }
             },
         );
 
-        let hidpi_factor = match dpi_env {
+        let scale_factor = match dpi_env {
             EnvVarDPI::Randr => calc_dpi_factor(
                 ((*crtc).width as u32, (*crtc).height as u32),
                 (
@@ -128,9 +134,9 @@ impl XConnection {
                 ),
             ),
             EnvVarDPI::Scale(dpi_override) => {
-                if !validate_hidpi_factor(dpi_override) {
+                if !validate_scale_factor(dpi_override) {
                     panic!(
-                        "`WINIT_HIDPI_FACTOR` invalid; DPI factors must be either normal floats greater than 0, or `randr`. Got `{}`",
+                        "`WINIT_X11_SCALE_FACTOR` invalid; DPI factors must be either normal floats greater than 0, or `randr`. Got `{}`",
                         dpi_override,
                     );
                 }
@@ -152,7 +158,7 @@ impl XConnection {
         };
 
         (self.xrandr.XRRFreeOutputInfo)(output_info);
-        Some((name, hidpi_factor, modes))
+        Some((name, scale_factor, modes))
     }
     pub fn set_crtc_config(&self, crtc_id: RRCrtc, mode_id: RRMode) -> Result<(), ()> {
         unsafe {

src/platform_impl/linux/x11/util/window_property.rs

@@ -26,6 +26,7 @@ impl GetPropertyError {
 const PROPERTY_BUFFER_SIZE: c_long = 1024; // 4k of RAM ought to be enough for anyone!
 
 #[derive(Debug)]
+#[allow(dead_code)]
 pub enum PropMode {
     Replace = ffi::PropModeReplace as isize,
     Prepend = ffi::PropModePrepend as isize,

src/platform_impl/linux/x11/window.rs

@@ -15,7 +15,7 @@ use libc;
 use parking_lot::Mutex;
 
 use crate::{
-    dpi::{LogicalPosition, LogicalSize},
+    dpi::{PhysicalPosition, PhysicalSize, Position, Size},
     error::{ExternalError, NotSupportedError, OsError as RootOsError},
     monitor::{MonitorHandle as RootMonitorHandle, VideoMode as RootVideoMode},
     platform_impl::{
@@ -36,7 +36,7 @@ pub struct SharedState {
     pub inner_position: Option<(i32, i32)>,
     pub inner_position_rel_parent: Option<(i32, i32)>,
     pub last_monitor: X11MonitorHandle,
-    pub dpi_adjusted: Option<(f64, f64)>,
+    pub dpi_adjusted: Option<(u32, u32)>,
     pub fullscreen: Option<Fullscreen>,
     // Set when application calls `set_fullscreen` when window is not visible
     pub desired_fullscreen: Option<Option<Fullscreen>>,
@@ -45,8 +45,10 @@ pub struct SharedState {
     // Used to restore video mode after exiting fullscreen
     pub desktop_video_mode: Option<(ffi::RRCrtc, ffi::RRMode)>,
     pub frame_extents: Option<util::FrameExtentsHeuristic>,
-    pub min_inner_size: Option<LogicalSize>,
-    pub max_inner_size: Option<LogicalSize>,
+    pub min_inner_size: Option<Size>,
+    pub max_inner_size: Option<Size>,
+    pub resize_increments: Option<Size>,
+    pub base_size: Option<Size>,
     pub visibility: Visibility,
 }
 
@@ -83,6 +85,8 @@ impl SharedState {
             frame_extents: None,
             min_inner_size: None,
             max_inner_size: None,
+            resize_increments: None,
+            base_size: None,
         })
     }
 }
@@ -132,24 +136,24 @@ impl UnownedWindow {
                 })
                 .unwrap_or_else(|| monitors.swap_remove(0))
         };
-        let dpi_factor = guessed_monitor.hidpi_factor();
+        let scale_factor = guessed_monitor.scale_factor();
 
-        info!("Guessed window DPI factor: {}", dpi_factor);
+        info!("Guessed window scale factor: {}", scale_factor);
 
         let max_inner_size: Option<(u32, u32)> = window_attrs
             .max_inner_size
-            .map(|size| size.to_physical(dpi_factor).into());
+            .map(|size| size.to_physical::<u32>(scale_factor).into());
         let min_inner_size: Option<(u32, u32)> = window_attrs
             .min_inner_size
-            .map(|size| size.to_physical(dpi_factor).into());
+            .map(|size| size.to_physical::<u32>(scale_factor).into());
 
         let dimensions = {
             // x11 only applies constraints when the window is actively resized
             // by the user, so we have to manually apply the initial constraints
             let mut dimensions: (u32, u32) = window_attrs
                 .inner_size
+                .map(|size| size.to_physical::<u32>(scale_factor))
                 .or_else(|| Some((800, 600).into()))
-                .map(|size| size.to_physical(dpi_factor))
                 .map(Into::into)
                 .unwrap();
             if let Some(max) = max_inner_size {
@@ -235,7 +239,7 @@ impl UnownedWindow {
             )
         };
 
-        let window = UnownedWindow {
+        let mut window = UnownedWindow {
             xconn: Arc::clone(xconn),
             xwindow,
             root,
@@ -320,10 +324,11 @@ impl UnownedWindow {
             {
                 let mut min_inner_size = window_attrs
                     .min_inner_size
-                    .map(|size| size.to_physical(dpi_factor));
+                    .map(|size| size.to_physical::<u32>(scale_factor));
                 let mut max_inner_size = window_attrs
                     .max_inner_size
-                    .map(|size| size.to_physical(dpi_factor));
+                    .map(|size| size.to_physical::<u32>(scale_factor));
+
                 if !window_attrs.resizable {
                     if util::wm_name_is_one_of(&["Xfwm4"]) {
                         warn!("To avoid a WM bug, disabling resizing has no effect on Xfwm4");
@@ -331,9 +336,11 @@ impl UnownedWindow {
                         max_inner_size = Some(dimensions.into());
                         min_inner_size = Some(dimensions.into());
 
-                        let mut shared_state_lock = window.shared_state.lock();
-                        shared_state_lock.min_inner_size = window_attrs.min_inner_size;
-                        shared_state_lock.max_inner_size = window_attrs.max_inner_size;
+                        let mut shared_state = window.shared_state.get_mut();
+                        shared_state.min_inner_size = window_attrs.min_inner_size;
+                        shared_state.max_inner_size = window_attrs.max_inner_size;
+                        shared_state.resize_increments = pl_attribs.resize_increments;
+                        shared_state.base_size = pl_attribs.base_size;
                     }
                 }
 
@@ -341,8 +348,16 @@ impl UnownedWindow {
                 normal_hints.set_size(Some(dimensions));
                 normal_hints.set_min_size(min_inner_size.map(Into::into));
                 normal_hints.set_max_size(max_inner_size.map(Into::into));
-                normal_hints.set_resize_increments(pl_attribs.resize_increments);
-                normal_hints.set_base_size(pl_attribs.base_size);
+                normal_hints.set_resize_increments(
+                    pl_attribs
+                        .resize_increments
+                        .map(|size| size.to_physical::<u32>(scale_factor).into()),
+                );
+                normal_hints.set_base_size(
+                    pl_attribs
+                        .base_size
+                        .map(|size| size.to_physical::<u32>(scale_factor).into()),
+                );
                 xconn.set_normal_hints(window.xwindow, normal_hints).queue();
             }
 
@@ -440,16 +455,6 @@ impl UnownedWindow {
             .map_err(|x_err| os_error!(OsError::XError(x_err)))
     }
 
-    fn logicalize_coords(&self, (x, y): (i32, i32)) -> LogicalPosition {
-        let dpi = self.hidpi_factor();
-        LogicalPosition::from_physical((x, y), dpi)
-    }
-
-    fn logicalize_size(&self, (width, height): (u32, u32)) -> LogicalSize {
-        let dpi = self.hidpi_factor();
-        LogicalSize::from_physical((width, height), dpi)
-    }
-
     fn set_pid(&self) -> Option<util::Flusher<'_>> {
         let pid_atom = unsafe { self.xconn.get_atom_unchecked(b"_NET_WM_PID\0") };
         let client_machine_atom = unsafe { self.xconn.get_atom_unchecked(b"WM_CLIENT_MACHINE\0") };
@@ -951,11 +956,11 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn outer_position(&self) -> Result<LogicalPosition, NotSupportedError> {
+    pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         let extents = (*self.shared_state.lock()).frame_extents.clone();
         if let Some(extents) = extents {
-            let logical = self.inner_position().unwrap();
-            Ok(extents.inner_pos_to_outer_logical(logical, self.hidpi_factor()))
+            let (x, y) = self.inner_position_physical();
+            Ok(extents.inner_pos_to_outer(x, y).into())
         } else {
             self.update_cached_frame_extents();
             self.outer_position()
@@ -972,8 +977,8 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn inner_position(&self) -> Result<LogicalPosition, NotSupportedError> {
-        Ok(self.logicalize_coords(self.inner_position_physical()))
+    pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
+        Ok(self.inner_position_physical().into())
     }
 
     pub(crate) fn set_position_inner(&self, mut x: i32, mut y: i32) -> util::Flusher<'_> {
@@ -1002,8 +1007,8 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn set_outer_position(&self, logical_position: LogicalPosition) {
-        let (x, y) = logical_position.to_physical(self.hidpi_factor()).into();
+    pub fn set_outer_position(&self, position: Position) {
+        let (x, y) = position.to_physical::<i32>(self.scale_factor()).into();
         self.set_position_physical(x, y);
     }
 
@@ -1017,16 +1022,16 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn inner_size(&self) -> LogicalSize {
-        self.logicalize_size(self.inner_size_physical())
+    pub fn inner_size(&self) -> PhysicalSize<u32> {
+        self.inner_size_physical().into()
     }
 
     #[inline]
-    pub fn outer_size(&self) -> LogicalSize {
+    pub fn outer_size(&self) -> PhysicalSize<u32> {
         let extents = self.shared_state.lock().frame_extents.clone();
         if let Some(extents) = extents {
-            let logical = self.inner_size();
-            extents.inner_size_to_outer_logical(logical, self.hidpi_factor())
+            let (width, height) = self.inner_size_physical();
+            extents.inner_size_to_outer(width, height).into()
         } else {
             self.update_cached_frame_extents();
             self.outer_size()
@@ -1047,9 +1052,9 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn set_inner_size(&self, logical_size: LogicalSize) {
-        let dpi_factor = self.hidpi_factor();
-        let (width, height) = logical_size.to_physical(dpi_factor).into();
+    pub fn set_inner_size(&self, size: Size) {
+        let scale_factor = self.scale_factor();
+        let (width, height) = size.to_physical::<u32>(scale_factor).into();
         self.set_inner_size_physical(width, height);
     }
 
@@ -1070,10 +1075,10 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn set_min_inner_size(&self, logical_dimensions: Option<LogicalSize>) {
-        self.shared_state.lock().min_inner_size = logical_dimensions;
-        let physical_dimensions = logical_dimensions
-            .map(|logical_dimensions| logical_dimensions.to_physical(self.hidpi_factor()).into());
+    pub fn set_min_inner_size(&self, dimensions: Option<Size>) {
+        self.shared_state.lock().min_inner_size = dimensions;
+        let physical_dimensions =
+            dimensions.map(|dimensions| dimensions.to_physical::<u32>(self.scale_factor()).into());
         self.set_min_inner_size_physical(physical_dimensions);
     }
 
@@ -1083,48 +1088,40 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn set_max_inner_size(&self, logical_dimensions: Option<LogicalSize>) {
-        self.shared_state.lock().max_inner_size = logical_dimensions;
-        let physical_dimensions = logical_dimensions
-            .map(|logical_dimensions| logical_dimensions.to_physical(self.hidpi_factor()).into());
+    pub fn set_max_inner_size(&self, dimensions: Option<Size>) {
+        self.shared_state.lock().max_inner_size = dimensions;
+        let physical_dimensions =
+            dimensions.map(|dimensions| dimensions.to_physical::<u32>(self.scale_factor()).into());
         self.set_max_inner_size_physical(physical_dimensions);
     }
 
     pub(crate) fn adjust_for_dpi(
         &self,
-        old_dpi_factor: f64,
-        new_dpi_factor: f64,
-        width: f64,
-        height: f64,
-    ) -> (f64, f64, util::Flusher<'_>) {
-        let scale_factor = new_dpi_factor / old_dpi_factor;
-        let new_width = width * scale_factor;
-        let new_height = height * scale_factor;
+        old_scale_factor: f64,
+        new_scale_factor: f64,
+        width: u32,
+        height: u32,
+        shared_state: &SharedState,
+    ) -> (u32, u32) {
+        let scale_factor = new_scale_factor / old_scale_factor;
         self.update_normal_hints(|normal_hints| {
-            let dpi_adjuster = |(width, height): (u32, u32)| -> (u32, u32) {
-                let new_width = width as f64 * scale_factor;
-                let new_height = height as f64 * scale_factor;
-                (new_width.round() as u32, new_height.round() as u32)
-            };
-            let max_size = normal_hints.get_max_size().map(&dpi_adjuster);
-            let min_size = normal_hints.get_min_size().map(&dpi_adjuster);
-            let resize_increments = normal_hints.get_resize_increments().map(&dpi_adjuster);
-            let base_size = normal_hints.get_base_size().map(&dpi_adjuster);
+            let dpi_adjuster =
+                |size: Size| -> (u32, u32) { size.to_physical::<u32>(new_scale_factor).into() };
+            let max_size = shared_state.max_inner_size.map(&dpi_adjuster);
+            let min_size = shared_state.min_inner_size.map(&dpi_adjuster);
+            let resize_increments = shared_state.resize_increments.map(&dpi_adjuster);
+            let base_size = shared_state.base_size.map(&dpi_adjuster);
             normal_hints.set_max_size(max_size);
             normal_hints.set_min_size(min_size);
             normal_hints.set_resize_increments(resize_increments);
             normal_hints.set_base_size(base_size);
         })
         .expect("Failed to update normal hints");
-        unsafe {
-            (self.xconn.xlib.XResizeWindow)(
-                self.xconn.display,
-                self.xwindow,
-                new_width.round() as c_uint,
-                new_height.round() as c_uint,
-            );
-        }
-        (new_width, new_height, util::Flusher::new(&self.xconn))
+
+        let new_width = (width as f64 * scale_factor).round() as u32;
+        let new_height = (height as f64 * scale_factor).round() as u32;
+
+        (new_width, new_height)
     }
 
     pub fn set_resizable(&self, resizable: bool) {
@@ -1136,25 +1133,25 @@ impl UnownedWindow {
             return;
         }
 
-        let (logical_min, logical_max) = if resizable {
+        let (min_size, max_size) = if resizable {
             let shared_state_lock = self.shared_state.lock();
             (
                 shared_state_lock.min_inner_size,
                 shared_state_lock.max_inner_size,
             )
         } else {
-            let window_size = Some(self.inner_size());
+            let window_size = Some(Size::from(self.inner_size()));
             (window_size.clone(), window_size)
         };
 
         self.set_maximizable_inner(resizable).queue();
 
-        let dpi_factor = self.hidpi_factor();
-        let min_inner_size = logical_min
-            .map(|logical_size| logical_size.to_physical(dpi_factor))
+        let scale_factor = self.scale_factor();
+        let min_inner_size = min_size
+            .map(|size| size.to_physical::<u32>(scale_factor))
             .map(Into::into);
-        let max_inner_size = logical_max
-            .map(|logical_size| logical_size.to_physical(dpi_factor))
+        let max_inner_size = max_size
+            .map(|size| size.to_physical::<u32>(scale_factor))
             .map(Into::into);
         self.update_normal_hints(|normal_hints| {
             normal_hints.set_min_size(min_inner_size);
@@ -1275,8 +1272,8 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f64 {
-        self.current_monitor().hidpi_factor
+    pub fn scale_factor(&self) -> f64 {
+        self.current_monitor().scale_factor
     }
 
     pub fn set_cursor_position_physical(&self, x: i32, y: i32) -> Result<(), ExternalError> {
@@ -1289,11 +1286,8 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn set_cursor_position(
-        &self,
-        logical_position: LogicalPosition,
-    ) -> Result<(), ExternalError> {
-        let (x, y) = logical_position.to_physical(self.hidpi_factor()).into();
+    pub fn set_cursor_position(&self, position: Position) -> Result<(), ExternalError> {
+        let (x, y) = position.to_physical::<i32>(self.scale_factor()).into();
         self.set_cursor_position_physical(x, y)
     }
 
@@ -1305,8 +1299,8 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn set_ime_position(&self, logical_spot: LogicalPosition) {
-        let (x, y) = logical_spot.to_physical(self.hidpi_factor()).into();
+    pub fn set_ime_position(&self, spot: Position) {
+        let (x, y) = spot.to_physical::<i32>(self.scale_factor()).into();
         self.set_ime_position_physical(x, y);
     }
 

src/platform_impl/linux/x11/xdisplay.rs

@@ -111,12 +111,7 @@ pub struct XError {
     pub minor_code: u8,
 }
 
-impl Error for XError {
-    #[inline]
-    fn description(&self) -> &str {
-        &self.description
-    }
-}
+impl Error for XError {}
 
 impl fmt::Display for XError {
     fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
@@ -144,17 +139,18 @@ impl From<ffi::OpenError> for XNotSupported {
     }
 }
 
-impl Error for XNotSupported {
-    #[inline]
-    fn description(&self) -> &str {
-        match *self {
+impl XNotSupported {
+    fn description(&self) -> &'static str {
+        match self {
             XNotSupported::LibraryOpenError(_) => "Failed to load one of xlib's shared libraries",
             XNotSupported::XOpenDisplayFailed => "Failed to open connection to X server",
         }
     }
+}
 
+impl Error for XNotSupported {
     #[inline]
-    fn cause(&self) -> Option<&dyn Error> {
+    fn source(&self) -> Option<&(dyn Error + 'static)> {
         match *self {
             XNotSupported::LibraryOpenError(ref err) => Some(err),
             _ => None,

src/platform_impl/macos/activation_hack.rs

@@ -0,0 +1,208 @@
+// Normally when you run or distribute a macOS app, it's bundled: it's in one
+// of those fun little folders that you have to right click "Show Package
+// Contents" on, and usually contains myriad delights including, but not
+// limited to, plists, icons, and of course, your beloved executable. However,
+// when you use `cargo run`, your app is unbundled - it's just a lonely, bare
+// executable.
+//
+// Apple isn't especially fond of unbundled apps, which is to say, they seem to
+// barely be supported. If you move the mouse while opening a winit window from
+// an unbundled app, the window will fail to activate and be in a grayed-out
+// uninteractable state. Switching to another app and back is the only way to
+// get the winit window into a normal state. None of this happens if the app is
+// bundled, i.e. when running via Xcode.
+//
+// To workaround this, we just switch focus to the Dock and then switch back to
+// our app. We only do this for unbundled apps, and only when they fail to
+// become active on their own.
+//
+// This solution was derived from this Godot PR:
+// https://github.com/godotengine/godot/pull/17187
+// (which appears to be based on https://stackoverflow.com/a/7602677)
+// The curious specialness of mouse motions is touched upon here:
+// https://github.com/godotengine/godot/issues/8653#issuecomment-358130512
+//
+// We omit the 2nd step of the solution used in Godot, since it appears to have
+// no effect - I speculate that it's just technical debt picked up from the SO
+// answer; the API used is fairly exotic, and was historically used for very
+// old versions of macOS that didn't support `activateIgnoringOtherApps`, i.e.
+// in previous versions of SDL:
+// https://hg.libsdl.org/SDL/file/c0bcc39a3491/src/video/cocoa/SDL_cocoaevents.m#l322
+//
+// The `performSelector` delays in the Godot solution are used for sequencing,
+// since refocusing the app will fail if the call is made before it finishes
+// unfocusing. The delays used there are much smaller than the ones in the
+// original SO answer, presumably because they found the fastest delay that
+// works reliably through trial and error. Instead of using delays, we just
+// handle `applicationDidResignActive`; despite the app not activating reliably,
+// that still triggers when we switch focus to the Dock.
+//
+// The Godot solution doesn't appear to skip the hack when an unbundled app
+// activates normally. Checking for this is difficult, since if you call
+// `isActive` too early, it will always be `NO`. Even though we receive
+// `applicationDidResignActive` when switching focus to the Dock, we never
+// receive a preceding `applicationDidBecomeActive` if the app fails to
+// activate normally. I wasn't able to find a proper point in time to perform
+// the `isActive` check, so we instead check for the cause of the quirk: if
+// any mouse motion occurs prior to us receiving `applicationDidResignActive`,
+// we assume the app failed to become active.
+//
+// Fun fact: this issue is still present in GLFW
+// (https://github.com/glfw/glfw/issues/1515)
+//
+// A similar issue was found in SDL, but the resolution doesn't seem to work
+// for us: https://bugzilla.libsdl.org/show_bug.cgi?id=3051
+
+use super::util;
+use cocoa::{
+    appkit::{NSApp, NSApplicationActivateIgnoringOtherApps},
+    base::id,
+    foundation::NSUInteger,
+};
+use objc::runtime::{Object, Sel, BOOL, NO, YES};
+use std::{
+    os::raw::c_void,
+    sync::atomic::{AtomicBool, Ordering},
+};
+
+#[derive(Debug, Default)]
+pub struct State {
+    // Indicates that the hack has either completed or been skipped.
+    activated: AtomicBool,
+    // Indicates that the mouse has moved at some point in time.
+    mouse_moved: AtomicBool,
+    // Indicates that the hack is in progress, and that we should refocus when
+    // the app resigns active.
+    needs_refocus: AtomicBool,
+}
+
+impl State {
+    pub fn name() -> &'static str {
+        "activationHackState"
+    }
+
+    pub fn new() -> *mut c_void {
+        let this = Box::new(Self::default());
+        Box::into_raw(this) as *mut c_void
+    }
+
+    pub unsafe fn free(this: *mut Self) {
+        Box::from_raw(this);
+    }
+
+    pub unsafe fn get_ptr(obj: &Object) -> *mut Self {
+        let this: *mut c_void = *(*obj).get_ivar(Self::name());
+        assert!(!this.is_null(), "`activationHackState` pointer was null");
+        this as *mut Self
+    }
+
+    pub unsafe fn set_activated(obj: &Object, value: bool) {
+        let this = Self::get_ptr(obj);
+        (*this).activated.store(value, Ordering::Release);
+    }
+
+    unsafe fn get_activated(obj: &Object) -> bool {
+        let this = Self::get_ptr(obj);
+        (*this).activated.load(Ordering::Acquire)
+    }
+
+    pub unsafe fn set_mouse_moved(obj: &Object, value: bool) {
+        let this = Self::get_ptr(obj);
+        (*this).mouse_moved.store(value, Ordering::Release);
+    }
+
+    pub unsafe fn get_mouse_moved(obj: &Object) -> bool {
+        let this = Self::get_ptr(obj);
+        (*this).mouse_moved.load(Ordering::Acquire)
+    }
+
+    pub unsafe fn set_needs_refocus(obj: &Object, value: bool) {
+        let this = Self::get_ptr(obj);
+        (*this).needs_refocus.store(value, Ordering::Release);
+    }
+
+    unsafe fn get_needs_refocus(obj: &Object) -> bool {
+        let this = Self::get_ptr(obj);
+        (*this).needs_refocus.load(Ordering::Acquire)
+    }
+}
+
+// This is the entry point for the hack - if the app is unbundled and a mouse
+// movement occurs before the app activates, it will trigger the hack. Because
+// mouse movements prior to activation are the cause of this quirk, they should
+// be a reliable way to determine if the hack needs to be performed.
+pub extern "C" fn mouse_moved(this: &Object, _: Sel, _: id) {
+    trace!("Triggered `activationHackMouseMoved`");
+    unsafe {
+        if !State::get_activated(this) {
+            // We check if `CFBundleName` is undefined to determine if the
+            // app is unbundled.
+            if let None = util::app_name() {
+                info!("App detected as unbundled");
+                unfocus(this);
+            } else {
+                info!("App detected as bundled");
+            }
+        }
+    }
+    trace!("Completed `activationHackMouseMoved`");
+}
+
+// Switch focus to the dock.
+unsafe fn unfocus(this: &Object) {
+    // We only perform the hack if the app failed to activate, since otherwise,
+    // there'd be a gross (but fast) flicker as it unfocused and then refocused.
+    // However, we only enter this function if we detect mouse movement prior
+    // to activation, so this should always be `NO`.
+    //
+    // Note that this check isn't necessarily reliable in detecting a violation
+    // of the invariant above, since it's not guaranteed that activation will
+    // resolve before this point. In other words, it can spuriously return `NO`.
+    // This is also why the mouse motion approach was chosen, since it's not
+    // obvious how to sequence this check - if someone knows how to, then that
+    // would almost surely be a cleaner approach.
+    let active: BOOL = msg_send![NSApp(), isActive];
+    if active == YES {
+        error!("Unbundled app activation hack triggered on an app that's already active; this shouldn't happen!");
+    } else {
+        info!("Performing unbundled app activation hack");
+        let dock_bundle_id = util::ns_string_id_ref("com.apple.dock");
+        let dock_array: id = msg_send![
+            class!(NSRunningApplication),
+            runningApplicationsWithBundleIdentifier: *dock_bundle_id
+        ];
+        let dock_array_len: NSUInteger = msg_send![dock_array, count];
+        if dock_array_len == 0 {
+            error!("The Dock doesn't seem to be running, so switching focus to it is impossible");
+        } else {
+            State::set_needs_refocus(this, true);
+            let dock: id = msg_send![dock_array, objectAtIndex: 0];
+            // This will trigger `applicationDidResignActive`, which will in
+            // turn call `refocus`.
+            let status: BOOL = msg_send![
+                dock,
+                activateWithOptions: NSApplicationActivateIgnoringOtherApps
+            ];
+            if status == NO {
+                error!("Failed to switch focus to Dock");
+            }
+        }
+    }
+}
+
+// Switch focus back to our app, causing the user to rejoice!
+pub unsafe fn refocus(this: &Object) {
+    if State::get_needs_refocus(this) {
+        State::set_needs_refocus(this, false);
+        let app: id = msg_send![class!(NSRunningApplication), currentApplication];
+        // Simply calling `NSApp activateIgnoringOtherApps` doesn't work. The
+        // nuanced difference isn't clear to me, but hey, I tried.
+        let success: BOOL = msg_send![
+            app,
+            activateWithOptions: NSApplicationActivateIgnoringOtherApps
+        ];
+        if success == NO {
+            error!("Failed to refocus app");
+        }
+    }
+}

src/platform_impl/macos/app.rs

@@ -2,17 +2,15 @@ use std::collections::VecDeque;
 
 use cocoa::{
     appkit::{self, NSEvent},
-    base::id,
+    base::{id, nil},
 };
 use objc::{
     declare::ClassDecl,
     runtime::{Class, Object, Sel},
 };
 
-use crate::{
-    event::{DeviceEvent, ElementState, Event},
-    platform_impl::platform::{app_state::AppState, util, DEVICE_ID},
-};
+use super::{activation_hack, app_state::AppState, event::EventWrapper, util, DEVICE_ID};
+use crate::event::{DeviceEvent, ElementState, Event};
 
 pub struct AppClass(pub *const Class);
 unsafe impl Send for AppClass {}
@@ -51,14 +49,14 @@ extern "C" fn send_event(this: &Object, _sel: Sel, event: id) {
             let key_window: id = msg_send![this, keyWindow];
             let _: () = msg_send![key_window, sendEvent: event];
         } else {
-            maybe_dispatch_device_event(event);
+            maybe_dispatch_device_event(this, event);
             let superclass = util::superclass(this);
             let _: () = msg_send![super(this, superclass), sendEvent: event];
         }
     }
 }
 
-unsafe fn maybe_dispatch_device_event(event: id) {
+unsafe fn maybe_dispatch_device_event(this: &Object, event: id) {
     let event_type = event.eventType();
     match event_type {
         appkit::NSMouseMoved
@@ -71,59 +69,74 @@ unsafe fn maybe_dispatch_device_event(event: id) {
             let delta_y = event.deltaY() as f64;
 
             if delta_x != 0.0 {
-                events.push_back(Event::DeviceEvent {
+                events.push_back(EventWrapper::StaticEvent(Event::DeviceEvent {
                     device_id: DEVICE_ID,
                     event: DeviceEvent::Motion {
                         axis: 0,
                         value: delta_x,
                     },
-                });
+                }));
             }
 
             if delta_y != 0.0 {
-                events.push_back(Event::DeviceEvent {
+                events.push_back(EventWrapper::StaticEvent(Event::DeviceEvent {
                     device_id: DEVICE_ID,
                     event: DeviceEvent::Motion {
                         axis: 1,
                         value: delta_y,
                     },
-                });
+                }));
             }
 
             if delta_x != 0.0 || delta_y != 0.0 {
-                events.push_back(Event::DeviceEvent {
+                events.push_back(EventWrapper::StaticEvent(Event::DeviceEvent {
                     device_id: DEVICE_ID,
                     event: DeviceEvent::MouseMotion {
                         delta: (delta_x, delta_y),
                     },
-                });
+                }));
             }
 
             AppState::queue_events(events);
+
+            // Notify the delegate when the first mouse move occurs. This is
+            // used for the unbundled app activation hack, which needs to know
+            // if any mouse motions occurred prior to the app activating.
+            let delegate: id = msg_send![this, delegate];
+            assert_ne!(delegate, nil);
+            if !activation_hack::State::get_mouse_moved(&*delegate) {
+                activation_hack::State::set_mouse_moved(&*delegate, true);
+                let () = msg_send![
+                    delegate,
+                    performSelector: sel!(activationHackMouseMoved:)
+                    withObject: nil
+                    afterDelay: 0.0
+                ];
+            }
         }
         appkit::NSLeftMouseDown | appkit::NSRightMouseDown | appkit::NSOtherMouseDown => {
             let mut events = VecDeque::with_capacity(1);
 
-            events.push_back(Event::DeviceEvent {
+            events.push_back(EventWrapper::StaticEvent(Event::DeviceEvent {
                 device_id: DEVICE_ID,
                 event: DeviceEvent::Button {
                     button: event.buttonNumber() as u32,
                     state: ElementState::Pressed,
                 },
-            });
+            }));
 
             AppState::queue_events(events);
         }
         appkit::NSLeftMouseUp | appkit::NSRightMouseUp | appkit::NSOtherMouseUp => {
             let mut events = VecDeque::with_capacity(1);
 
-            events.push_back(Event::DeviceEvent {
+            events.push_back(EventWrapper::StaticEvent(Event::DeviceEvent {
                 device_id: DEVICE_ID,
                 event: DeviceEvent::Button {
                     button: event.buttonNumber() as u32,
                     state: ElementState::Released,
                 },
-            });
+            }));
 
             AppState::queue_events(events);
         }

src/platform_impl/macos/app_delegate.rs

@@ -1,10 +1,10 @@
+use super::{activation_hack, app_state::AppState};
 use cocoa::base::id;
 use objc::{
     declare::ClassDecl,
-    runtime::{Class, Object, Sel, BOOL, YES},
+    runtime::{Class, Object, Sel},
 };
-
-use crate::platform_impl::platform::app_state::AppState;
+use std::os::raw::c_void;
 
 pub struct AppDelegateClass(pub *const Class);
 unsafe impl Send for AppDelegateClass {}
@@ -15,90 +15,67 @@ lazy_static! {
         let superclass = class!(NSResponder);
         let mut decl = ClassDecl::new("WinitAppDelegate", superclass).unwrap();
 
+        decl.add_class_method(sel!(new), new as extern "C" fn(&Class, Sel) -> id);
+        decl.add_method(sel!(dealloc), dealloc as extern "C" fn(&Object, Sel));
         decl.add_method(
             sel!(applicationDidFinishLaunching:),
-            did_finish_launching as extern "C" fn(&Object, Sel, id) -> BOOL,
+            did_finish_launching as extern "C" fn(&Object, Sel, id),
         );
         decl.add_method(
             sel!(applicationDidBecomeActive:),
             did_become_active as extern "C" fn(&Object, Sel, id),
         );
         decl.add_method(
-            sel!(applicationWillResignActive:),
-            will_resign_active as extern "C" fn(&Object, Sel, id),
+            sel!(applicationDidResignActive:),
+            did_resign_active as extern "C" fn(&Object, Sel, id),
         );
+
+        decl.add_ivar::<*mut c_void>(activation_hack::State::name());
         decl.add_method(
-            sel!(applicationWillEnterForeground:),
-            will_enter_foreground as extern "C" fn(&Object, Sel, id),
-        );
-        decl.add_method(
-            sel!(applicationDidEnterBackground:),
-            did_enter_background as extern "C" fn(&Object, Sel, id),
-        );
-        decl.add_method(
-            sel!(applicationWillTerminate:),
-            will_terminate as extern "C" fn(&Object, Sel, id),
+            sel!(activationHackMouseMoved:),
+            activation_hack::mouse_moved as extern "C" fn(&Object, Sel, id),
         );
 
         AppDelegateClass(decl.register())
     };
 }
 
-extern "C" fn did_finish_launching(_: &Object, _: Sel, _: id) -> BOOL {
-    trace!("Triggered `didFinishLaunching`");
+extern "C" fn new(class: &Class, _: Sel) -> id {
+    unsafe {
+        let this: id = msg_send![class, alloc];
+        let this: id = msg_send![this, init];
+        (*this).set_ivar(
+            activation_hack::State::name(),
+            activation_hack::State::new(),
+        );
+        this
+    }
+}
+
+extern "C" fn dealloc(this: &Object, _: Sel) {
+    unsafe {
+        activation_hack::State::free(activation_hack::State::get_ptr(this));
+    }
+}
+
+extern "C" fn did_finish_launching(_: &Object, _: Sel, _: id) {
+    trace!("Triggered `applicationDidFinishLaunching`");
     AppState::launched();
-    trace!("Completed `didFinishLaunching`");
-    YES
+    trace!("Completed `applicationDidFinishLaunching`");
 }
 
-extern "C" fn did_become_active(_: &Object, _: Sel, _: id) {
-    trace!("Triggered `didBecomeActive`");
-    /*unsafe {
-        HANDLER.lock().unwrap().handle_nonuser_event(Event::Resumed)
-    }*/
-    trace!("Completed `didBecomeActive`");
+extern "C" fn did_become_active(this: &Object, _: Sel, _: id) {
+    trace!("Triggered `applicationDidBecomeActive`");
+    unsafe {
+        activation_hack::State::set_activated(this, true);
+    }
+    trace!("Completed `applicationDidBecomeActive`");
 }
 
-extern "C" fn will_resign_active(_: &Object, _: Sel, _: id) {
-    trace!("Triggered `willResignActive`");
-    /*unsafe {
-        HANDLER.lock().unwrap().handle_nonuser_event(Event::Suspended)
-    }*/
-    trace!("Completed `willResignActive`");
-}
-
-extern "C" fn will_enter_foreground(_: &Object, _: Sel, _: id) {
-    trace!("Triggered `willEnterForeground`");
-    trace!("Completed `willEnterForeground`");
-}
-
-extern "C" fn did_enter_background(_: &Object, _: Sel, _: id) {
-    trace!("Triggered `didEnterBackground`");
-    trace!("Completed `didEnterBackground`");
-}
-
-extern "C" fn will_terminate(_: &Object, _: Sel, _: id) {
-    trace!("Triggered `willTerminate`");
-    /*unsafe {
-        let app: id = msg_send![class!(UIApplication), sharedApplication];
-        let windows: id = msg_send![app, windows];
-        let windows_enum: id = msg_send![windows, objectEnumerator];
-        let mut events = Vec::new();
-        loop {
-            let window: id = msg_send![windows_enum, nextObject];
-            if window == nil {
-                break
-            }
-            let is_winit_window: BOOL = msg_send![window, isKindOfClass:class!(WinitUIWindow)];
-            if is_winit_window == YES {
-                events.push(Event::WindowEvent {
-                    window_id: RootWindowId(window.into()),
-                    event: WindowEvent::Destroyed,
-                });
-            }
-        }
-        HANDLER.lock().unwrap().handle_nonuser_events(events);
-        HANDLER.lock().unwrap().terminated();
-    }*/
-    trace!("Completed `willTerminate`");
+extern "C" fn did_resign_active(this: &Object, _: Sel, _: id) {
+    trace!("Triggered `applicationDidResignActive`");
+    unsafe {
+        activation_hack::refocus(this);
+    }
+    trace!("Completed `applicationDidResignActive`");
 }

src/platform_impl/macos/app_state.rs

@@ -12,25 +12,32 @@ use std::{
 };
 
 use cocoa::{
-    appkit::NSApp,
-    base::nil,
-    foundation::{NSAutoreleasePool, NSString},
+    appkit::{NSApp, NSEventType::NSApplicationDefined, NSWindow},
+    base::{id, nil},
+    foundation::{NSAutoreleasePool, NSPoint, NSSize},
 };
 
+use objc::runtime::YES;
+
 use crate::{
-    event::{Event, StartCause},
+    dpi::LogicalSize,
+    event::{Event, StartCause, WindowEvent},
     event_loop::{ControlFlow, EventLoopWindowTarget as RootWindowTarget},
-    platform_impl::platform::{observer::EventLoopWaker, util::Never},
+    platform_impl::platform::{
+        event::{EventProxy, EventWrapper},
+        observer::EventLoopWaker,
+        util::{IdRef, Never},
+        window::get_window_id,
+    },
     window::WindowId,
 };
-use objc::runtime::Object;
 
 lazy_static! {
     static ref HANDLER: Handler = Default::default();
 }
 
-impl Event<Never> {
-    fn userify<T: 'static>(self) -> Event<T> {
+impl<'a, Never> Event<'a, Never> {
+    fn userify<T: 'static>(self) -> Event<'a, T> {
         self.map_nonuser_event()
             // `Never` can't be constructed, so the `UserEvent` variant can't
             // be present here.
@@ -39,12 +46,13 @@ impl Event<Never> {
 }
 
 pub trait EventHandler: Debug {
-    fn handle_nonuser_event(&mut self, event: Event<Never>, control_flow: &mut ControlFlow);
+    // Not sure probably it should accept Event<'static, Never>
+    fn handle_nonuser_event(&mut self, event: Event<'_, Never>, control_flow: &mut ControlFlow);
     fn handle_user_events(&mut self, control_flow: &mut ControlFlow);
 }
 
 struct EventLoopHandler<T: 'static> {
-    callback: Box<dyn FnMut(Event<T>, &RootWindowTarget<T>, &mut ControlFlow)>,
+    callback: Box<dyn FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow)>,
     will_exit: bool,
     window_target: Rc<RootWindowTarget<T>>,
 }
@@ -59,7 +67,7 @@ impl<T> Debug for EventLoopHandler<T> {
 }
 
 impl<T> EventHandler for EventLoopHandler<T> {
-    fn handle_nonuser_event(&mut self, event: Event<Never>, control_flow: &mut ControlFlow) {
+    fn handle_nonuser_event(&mut self, event: Event<'_, Never>, control_flow: &mut ControlFlow) {
         (self.callback)(event.userify(), &self.window_target, control_flow);
         self.will_exit |= *control_flow == ControlFlow::Exit;
         if self.will_exit {
@@ -88,7 +96,7 @@ struct Handler {
     control_flow_prev: Mutex<ControlFlow>,
     start_time: Mutex<Option<Instant>>,
     callback: Mutex<Option<Box<dyn EventHandler>>>,
-    pending_events: Mutex<VecDeque<Event<Never>>>,
+    pending_events: Mutex<VecDeque<EventWrapper>>,
     pending_redraw: Mutex<Vec<WindowId>>,
     waker: Mutex<EventLoopWaker>,
 }
@@ -97,7 +105,7 @@ unsafe impl Send for Handler {}
 unsafe impl Sync for Handler {}
 
 impl Handler {
-    fn events<'a>(&'a self) -> MutexGuard<'a, VecDeque<Event<Never>>> {
+    fn events(&self) -> MutexGuard<'_, VecDeque<EventWrapper>> {
         self.pending_events.lock().unwrap()
     }
 
@@ -105,7 +113,7 @@ impl Handler {
         self.pending_redraw.lock().unwrap()
     }
 
-    fn waker<'a>(&'a self) -> MutexGuard<'a, EventLoopWaker> {
+    fn waker(&self) -> MutexGuard<'_, EventLoopWaker> {
         self.waker.lock().unwrap()
     }
 
@@ -141,7 +149,7 @@ impl Handler {
         *self.start_time.lock().unwrap() = Some(Instant::now());
     }
 
-    fn take_events(&self) -> VecDeque<Event<Never>> {
+    fn take_events(&self) -> VecDeque<EventWrapper> {
         mem::replace(&mut *self.events(), Default::default())
     }
 
@@ -157,9 +165,14 @@ impl Handler {
         self.in_callback.store(in_callback, Ordering::Release);
     }
 
-    fn handle_nonuser_event(&self, event: Event<Never>) {
+    fn handle_nonuser_event(&self, wrapper: EventWrapper) {
         if let Some(ref mut callback) = *self.callback.lock().unwrap() {
-            callback.handle_nonuser_event(event, &mut *self.control_flow.lock().unwrap());
+            match wrapper {
+                EventWrapper::StaticEvent(event) => {
+                    callback.handle_nonuser_event(event, &mut *self.control_flow.lock().unwrap())
+                }
+                EventWrapper::EventProxy(proxy) => self.handle_proxy(proxy, callback),
+            }
         }
     }
 
@@ -168,6 +181,46 @@ impl Handler {
             callback.handle_user_events(&mut *self.control_flow.lock().unwrap());
         }
     }
+
+    fn handle_scale_factor_changed_event(
+        &self,
+        callback: &mut Box<dyn EventHandler + 'static>,
+        ns_window: IdRef,
+        suggested_size: LogicalSize<f64>,
+        scale_factor: f64,
+    ) {
+        let mut size = suggested_size.to_physical(scale_factor);
+        let new_inner_size = &mut size;
+        let event = Event::WindowEvent {
+            window_id: WindowId(get_window_id(*ns_window)),
+            event: WindowEvent::ScaleFactorChanged {
+                scale_factor,
+                new_inner_size,
+            },
+        };
+
+        callback.handle_nonuser_event(event, &mut *self.control_flow.lock().unwrap());
+
+        let physical_size = *new_inner_size;
+        let logical_size = physical_size.to_logical(scale_factor);
+        let size = NSSize::new(logical_size.width, logical_size.height);
+        unsafe { NSWindow::setContentSize_(*ns_window, size) };
+    }
+
+    fn handle_proxy(&self, proxy: EventProxy, callback: &mut Box<dyn EventHandler + 'static>) {
+        match proxy {
+            EventProxy::DpiChangedProxy {
+                ns_window,
+                suggested_size,
+                scale_factor,
+            } => self.handle_scale_factor_changed_event(
+                callback,
+                ns_window,
+                suggested_size,
+                scale_factor,
+            ),
+        }
+    }
 }
 
 pub enum AppState {}
@@ -176,7 +229,7 @@ impl AppState {
     // This function extends lifetime of `callback` to 'static as its side effect
     pub unsafe fn set_callback<F, T>(callback: F, window_target: Rc<RootWindowTarget<T>>)
     where
-        F: FnMut(Event<T>, &RootWindowTarget<T>, &mut ControlFlow),
+        F: FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow),
     {
         *HANDLER.callback.lock().unwrap() = Some(Box::new(EventLoopHandler {
             // This transmute is always safe, in case it was reached through `run`, since our
@@ -184,8 +237,8 @@ impl AppState {
             // they passed to callback will actually outlive it, some apps just can't move
             // everything to event loop, so this is something that they should care about.
             callback: mem::transmute::<
-                Box<dyn FnMut(Event<T>, &RootWindowTarget<T>, &mut ControlFlow)>,
-                Box<dyn FnMut(Event<T>, &RootWindowTarget<T>, &mut ControlFlow)>,
+                Box<dyn FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow)>,
+                Box<dyn FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow)>,
             >(Box::new(callback)),
             will_exit: false,
             window_target,
@@ -194,7 +247,7 @@ impl AppState {
 
     pub fn exit() {
         HANDLER.set_in_callback(true);
-        HANDLER.handle_nonuser_event(Event::LoopDestroyed);
+        HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::LoopDestroyed));
         HANDLER.set_in_callback(false);
         HANDLER.callback.lock().unwrap().take();
     }
@@ -203,7 +256,9 @@ impl AppState {
         HANDLER.set_ready();
         HANDLER.waker().start();
         HANDLER.set_in_callback(true);
-        HANDLER.handle_nonuser_event(Event::NewEvents(StartCause::Init));
+        HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::NewEvents(
+            StartCause::Init,
+        )));
         HANDLER.set_in_callback(false);
     }
 
@@ -234,7 +289,7 @@ impl AppState {
             ControlFlow::Exit => StartCause::Poll, //panic!("unexpected `ControlFlow::Exit`"),
         };
         HANDLER.set_in_callback(true);
-        HANDLER.handle_nonuser_event(Event::NewEvents(cause));
+        HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::NewEvents(cause)));
         HANDLER.set_in_callback(false);
     }
 
@@ -246,18 +301,18 @@ impl AppState {
         }
     }
 
-    pub fn queue_event(event: Event<Never>) {
+    pub fn queue_event(wrapper: EventWrapper) {
         if !unsafe { msg_send![class!(NSThread), isMainThread] } {
-            panic!("Event queued from different thread: {:#?}", event);
+            panic!("Event queued from different thread: {:#?}", wrapper);
         }
-        HANDLER.events().push_back(event);
+        HANDLER.events().push_back(wrapper);
     }
 
-    pub fn queue_events(mut events: VecDeque<Event<Never>>) {
+    pub fn queue_events(mut wrappers: VecDeque<EventWrapper>) {
         if !unsafe { msg_send![class!(NSThread), isMainThread] } {
-            panic!("Events queued from different thread: {:#?}", events);
+            panic!("Events queued from different thread: {:#?}", wrappers);
         }
-        HANDLER.events().append(&mut events);
+        HANDLER.events().append(&mut wrappers);
     }
 
     pub fn cleared() {
@@ -270,11 +325,13 @@ impl AppState {
             for event in HANDLER.take_events() {
                 HANDLER.handle_nonuser_event(event);
             }
-            HANDLER.handle_nonuser_event(Event::MainEventsCleared);
+            HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::MainEventsCleared));
             for window_id in HANDLER.should_redraw() {
-                HANDLER.handle_nonuser_event(Event::RedrawRequested(window_id));
+                HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::RedrawRequested(
+                    window_id,
+                )));
             }
-            HANDLER.handle_nonuser_event(Event::RedrawEventsCleared);
+            HANDLER.handle_nonuser_event(EventWrapper::StaticEvent(Event::RedrawEventsCleared));
             HANDLER.set_in_callback(false);
         }
         if HANDLER.should_exit() {
@@ -283,21 +340,23 @@ impl AppState {
 
                 let pool = NSAutoreleasePool::new(nil);
 
-                let windows: *const Object = msg_send![NSApp(), windows];
-                let window: *const Object = msg_send![windows, objectAtIndex:0];
+                let windows: id = msg_send![NSApp(), windows];
+                let window: id = msg_send![windows, objectAtIndex:0];
                 assert_ne!(window, nil);
 
-                let title: *const Object = msg_send![window, title];
-                assert_ne!(title, nil);
-                let postfix = NSString::alloc(nil).init_str("*");
-                let some_unique_title: *const Object =
-                    msg_send![title, stringByAppendingString: postfix];
-                assert_ne!(some_unique_title, nil);
-
-                // To stop event loop immediately, we need to send some UI event here.
-                let _: () = msg_send![window, setTitle: some_unique_title];
-                // And restore it.
-                let _: () = msg_send![window, setTitle: title];
+                let dummy_event: id = msg_send![class!(NSEvent),
+                    otherEventWithType: NSApplicationDefined
+                    location: NSPoint::new(0.0, 0.0)
+                    modifierFlags: 0
+                    timestamp: 0
+                    windowNumber: 0
+                    context: nil
+                    subtype: 0
+                    data1: 0
+                    data2: 0
+                ];
+                // To stop event loop immediately, we need to post some event here.
+                let _: () = msg_send![window, postEvent: dummy_event atStart: YES];
 
                 pool.drain();
             };

src/platform_impl/macos/event.rs

@@ -6,10 +6,29 @@ use cocoa::{
 };
 
 use crate::{
-    event::{ElementState, KeyboardInput, ModifiersState, VirtualKeyCode, WindowEvent},
-    platform_impl::platform::DEVICE_ID,
+    dpi::LogicalSize,
+    event::{ElementState, Event, KeyboardInput, ModifiersState, VirtualKeyCode, WindowEvent},
+    platform_impl::platform::{
+        util::{IdRef, Never},
+        DEVICE_ID,
+    },
 };
 
+#[derive(Debug)]
+pub enum EventWrapper {
+    StaticEvent(Event<'static, Never>),
+    EventProxy(EventProxy),
+}
+
+#[derive(Debug, PartialEq)]
+pub enum EventProxy {
+    DpiChangedProxy {
+        ns_window: IdRef,
+        suggested_size: LogicalSize<f64>,
+        scale_factor: f64,
+    },
+}
+
 pub fn char_to_keycode(c: char) -> Option<VirtualKeyCode> {
     // We only translate keys that are affected by keyboard layout.
     //
@@ -256,7 +275,7 @@ pub unsafe fn modifier_event(
     ns_event: id,
     keymask: NSEventModifierFlags,
     was_key_pressed: bool,
-) -> Option<WindowEvent> {
+) -> Option<WindowEvent<'static>> {
     if !was_key_pressed && NSEvent::modifierFlags(ns_event).contains(keymask)
         || was_key_pressed && !NSEvent::modifierFlags(ns_event).contains(keymask)
     {
@@ -268,6 +287,7 @@ pub unsafe fn modifier_event(
 
         let scancode = get_scancode(ns_event);
         let virtual_keycode = scancode_to_keycode(scancode);
+        #[allow(deprecated)]
         Some(WindowEvent::KeyboardInput {
             device_id: DEVICE_ID,
             input: KeyboardInput {

src/platform_impl/macos/event_loop.rs

@@ -84,7 +84,7 @@ impl<T> EventLoop<T> {
 
     pub fn run<F>(mut self, callback: F) -> !
     where
-        F: 'static + FnMut(Event<T>, &RootWindowTarget<T>, &mut ControlFlow),
+        F: 'static + FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow),
     {
         self.run_return(callback);
         process::exit(0);
@@ -92,7 +92,7 @@ impl<T> EventLoop<T> {
 
     pub fn run_return<F>(&mut self, callback: F)
     where
-        F: FnMut(Event<T>, &RootWindowTarget<T>, &mut ControlFlow),
+        F: FnMut(Event<'_, T>, &RootWindowTarget<T>, &mut ControlFlow),
     {
         unsafe {
             let pool = NSAutoreleasePool::new(nil);

src/platform_impl/macos/mod.rs

@@ -1,5 +1,6 @@
 #![cfg(target_os = "macos")]
 
+mod activation_hack;
 mod app;
 mod app_delegate;
 mod app_state;
@@ -24,6 +25,8 @@ use crate::{
     error::OsError as RootOsError, event::DeviceId as RootDeviceId, window::WindowAttributes,
 };
 
+pub(crate) use crate::icon::NoIcon as PlatformIcon;
+
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct DeviceId;
 

src/platform_impl/macos/monitor.rs

@@ -1,15 +1,14 @@
 use std::{collections::VecDeque, fmt};
 
-use super::ffi;
+use super::{ffi, util};
 use crate::{
     dpi::{PhysicalPosition, PhysicalSize},
     monitor::{MonitorHandle as RootMonitorHandle, VideoMode as RootVideoMode},
-    platform_impl::platform::util::IdRef,
 };
 use cocoa::{
     appkit::NSScreen,
     base::{id, nil},
-    foundation::{NSString, NSUInteger},
+    foundation::NSUInteger,
 };
 use core_foundation::{
     array::{CFArrayGetCount, CFArrayGetValueAtIndex},
@@ -84,7 +83,7 @@ impl Clone for NativeDisplayMode {
 }
 
 impl VideoMode {
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         self.size.into()
     }
 
@@ -166,9 +165,9 @@ impl fmt::Debug for MonitorHandle {
         struct MonitorHandle {
             name: Option<String>,
             native_identifier: u32,
-            size: PhysicalSize,
-            position: PhysicalPosition,
-            hidpi_factor: f64,
+            size: PhysicalSize<u32>,
+            position: PhysicalPosition<i32>,
+            scale_factor: f64,
         }
 
         let monitor_id_proxy = MonitorHandle {
@@ -176,7 +175,7 @@ impl fmt::Debug for MonitorHandle {
             native_identifier: self.native_identifier(),
             size: self.size(),
             position: self.position(),
-            hidpi_factor: self.hidpi_factor(),
+            scale_factor: self.scale_factor(),
         };
 
         monitor_id_proxy.fmt(f)
@@ -199,24 +198,24 @@ impl MonitorHandle {
         self.0
     }
 
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         let MonitorHandle(display_id) = *self;
         let display = CGDisplay::new(display_id);
         let height = display.pixels_high();
         let width = display.pixels_wide();
-        PhysicalSize::from_logical((width as f64, height as f64), self.hidpi_factor())
+        PhysicalSize::from_logical::<_, f64>((width as f64, height as f64), self.scale_factor())
     }
 
     #[inline]
-    pub fn position(&self) -> PhysicalPosition {
+    pub fn position(&self) -> PhysicalPosition<i32> {
         let bounds = unsafe { CGDisplayBounds(self.native_identifier()) };
-        PhysicalPosition::from_logical(
+        PhysicalPosition::from_logical::<_, f64>(
             (bounds.origin.x as f64, bounds.origin.y as f64),
-            self.hidpi_factor(),
+            self.scale_factor(),
         )
     }
 
-    pub fn hidpi_factor(&self) -> f64 {
+    pub fn scale_factor(&self) -> f64 {
         let screen = match self.ns_screen() {
             Some(screen) => screen,
             None => return 1.0, // default to 1.0 when we can't find the screen
@@ -303,7 +302,7 @@ impl MonitorHandle {
             let uuid = ffi::CGDisplayCreateUUIDFromDisplayID(self.0);
             let screens = NSScreen::screens(nil);
             let count: NSUInteger = msg_send![screens, count];
-            let key = IdRef::new(NSString::alloc(nil).init_str("NSScreenNumber"));
+            let key = util::ns_string_id_ref("NSScreenNumber");
             for i in 0..count {
                 let screen = msg_send![screens, objectAtIndex: i as NSUInteger];
                 let device_description = NSScreen::deviceDescription(screen);

src/platform_impl/macos/observer.rs

@@ -122,7 +122,7 @@ extern "C" fn control_flow_begin_handler(
 }
 
 // end is queued with the lowest priority to ensure it is processed after other observers
-// without that, LoopDestroyed would  get sent after EventsCleared
+// without that, LoopDestroyed would  get sent after MainEventsCleared
 extern "C" fn control_flow_end_handler(
     _: CFRunLoopObserverRef,
     activity: CFRunLoopActivity,

src/platform_impl/macos/util/async.rs

@@ -1,20 +1,36 @@
 use std::{
-    os::raw::c_void,
+    ops::Deref,
     sync::{Mutex, Weak},
 };
 
 use cocoa::{
     appkit::{CGFloat, NSScreen, NSWindow, NSWindowStyleMask},
     base::{id, nil},
-    foundation::{NSAutoreleasePool, NSPoint, NSSize, NSString},
+    foundation::{NSPoint, NSSize, NSString},
 };
-use dispatch::ffi::{dispatch_async_f, dispatch_get_main_queue, dispatch_sync_f};
+use dispatch::Queue;
+use objc::rc::autoreleasepool;
 
 use crate::{
     dpi::LogicalSize,
     platform_impl::platform::{ffi, util::IdRef, window::SharedState},
 };
 
+// Unsafe wrapper type that allows us to dispatch things that aren't Send.
+// This should *only* be used to dispatch to the main queue.
+// While it is indeed not guaranteed that these types can safely be sent to
+// other threads, we know that they're safe to use on the main thread.
+struct MainThreadSafe<T>(T);
+
+unsafe impl<T> Send for MainThreadSafe<T> {}
+
+impl<T> Deref for MainThreadSafe<T> {
+    type Target = T;
+    fn deref(&self) -> &T {
+        &self.0
+    }
+}
+
 unsafe fn set_style_mask(ns_window: id, ns_view: id, mask: NSWindowStyleMask) {
     ns_window.setStyleMask_(mask);
     // If we don't do this, key handling will break
@@ -22,203 +38,55 @@ unsafe fn set_style_mask(ns_window: id, ns_view: id, mask: NSWindowStyleMask) {
     ns_window.makeFirstResponder_(ns_view);
 }
 
-struct SetStyleMaskData {
-    ns_window: id,
-    ns_view: id,
-    mask: NSWindowStyleMask,
-}
-impl SetStyleMaskData {
-    fn new_ptr(ns_window: id, ns_view: id, mask: NSWindowStyleMask) -> *mut Self {
-        Box::into_raw(Box::new(SetStyleMaskData {
-            ns_window,
-            ns_view,
-            mask,
-        }))
-    }
-}
-extern "C" fn set_style_mask_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut SetStyleMaskData;
-        {
-            let context = &*context_ptr;
-            set_style_mask(context.ns_window, context.ns_view, context.mask);
-        }
-        Box::from_raw(context_ptr);
-    }
-}
 // Always use this function instead of trying to modify `styleMask` directly!
 // `setStyleMask:` isn't thread-safe, so we have to use Grand Central Dispatch.
 // Otherwise, this would vomit out errors about not being on the main thread
 // and fail to do anything.
 pub unsafe fn set_style_mask_async(ns_window: id, ns_view: id, mask: NSWindowStyleMask) {
-    let context = SetStyleMaskData::new_ptr(ns_window, ns_view, mask);
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        context as *mut _,
-        set_style_mask_callback,
-    );
+    let ns_window = MainThreadSafe(ns_window);
+    let ns_view = MainThreadSafe(ns_view);
+    Queue::main().exec_async(move || {
+        set_style_mask(*ns_window, *ns_view, mask);
+    });
 }
 pub unsafe fn set_style_mask_sync(ns_window: id, ns_view: id, mask: NSWindowStyleMask) {
-    let context = SetStyleMaskData::new_ptr(ns_window, ns_view, mask);
     if msg_send![class!(NSThread), isMainThread] {
-        set_style_mask_callback(context as *mut _);
+        set_style_mask(ns_window, ns_view, mask);
     } else {
-        dispatch_sync_f(
-            dispatch_get_main_queue(),
-            context as *mut _,
-            set_style_mask_callback,
-        );
+        let ns_window = MainThreadSafe(ns_window);
+        let ns_view = MainThreadSafe(ns_view);
+        Queue::main().exec_sync(move || {
+            set_style_mask(*ns_window, *ns_view, mask);
+        })
     }
 }
 
-struct SetContentSizeData {
-    ns_window: id,
-    size: LogicalSize,
-}
-impl SetContentSizeData {
-    fn new_ptr(ns_window: id, size: LogicalSize) -> *mut Self {
-        Box::into_raw(Box::new(SetContentSizeData { ns_window, size }))
-    }
-}
-extern "C" fn set_content_size_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut SetContentSizeData;
-        {
-            let context = &*context_ptr;
-            NSWindow::setContentSize_(
-                context.ns_window,
-                NSSize::new(
-                    context.size.width as CGFloat,
-                    context.size.height as CGFloat,
-                ),
-            );
-        }
-        Box::from_raw(context_ptr);
-    }
-}
 // `setContentSize:` isn't thread-safe either, though it doesn't log any errors
 // and just fails silently. Anyway, GCD to the rescue!
-pub unsafe fn set_content_size_async(ns_window: id, size: LogicalSize) {
-    let context = SetContentSizeData::new_ptr(ns_window, size);
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        context as *mut _,
-        set_content_size_callback,
-    );
+pub unsafe fn set_content_size_async(ns_window: id, size: LogicalSize<f64>) {
+    let ns_window = MainThreadSafe(ns_window);
+    Queue::main().exec_async(move || {
+        ns_window.setContentSize_(NSSize::new(size.width as CGFloat, size.height as CGFloat));
+    });
 }
 
-struct SetFrameTopLeftPointData {
-    ns_window: id,
-    point: NSPoint,
-}
-impl SetFrameTopLeftPointData {
-    fn new_ptr(ns_window: id, point: NSPoint) -> *mut Self {
-        Box::into_raw(Box::new(SetFrameTopLeftPointData { ns_window, point }))
-    }
-}
-extern "C" fn set_frame_top_left_point_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut SetFrameTopLeftPointData;
-        {
-            let context = &*context_ptr;
-            NSWindow::setFrameTopLeftPoint_(context.ns_window, context.point);
-        }
-        Box::from_raw(context_ptr);
-    }
-}
 // `setFrameTopLeftPoint:` isn't thread-safe, but fortunately has the courtesy
 // to log errors.
 pub unsafe fn set_frame_top_left_point_async(ns_window: id, point: NSPoint) {
-    let context = SetFrameTopLeftPointData::new_ptr(ns_window, point);
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        context as *mut _,
-        set_frame_top_left_point_callback,
-    );
+    let ns_window = MainThreadSafe(ns_window);
+    Queue::main().exec_async(move || {
+        ns_window.setFrameTopLeftPoint_(point);
+    });
 }
 
-struct SetLevelData {
-    ns_window: id,
-    level: ffi::NSWindowLevel,
-}
-impl SetLevelData {
-    fn new_ptr(ns_window: id, level: ffi::NSWindowLevel) -> *mut Self {
-        Box::into_raw(Box::new(SetLevelData { ns_window, level }))
-    }
-}
-extern "C" fn set_level_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut SetLevelData;
-        {
-            let context = &*context_ptr;
-            context.ns_window.setLevel_(context.level as _);
-        }
-        Box::from_raw(context_ptr);
-    }
-}
 // `setFrameTopLeftPoint:` isn't thread-safe, and fails silently.
 pub unsafe fn set_level_async(ns_window: id, level: ffi::NSWindowLevel) {
-    let context = SetLevelData::new_ptr(ns_window, level);
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        context as *mut _,
-        set_level_callback,
-    );
+    let ns_window = MainThreadSafe(ns_window);
+    Queue::main().exec_async(move || {
+        ns_window.setLevel_(level as _);
+    });
 }
 
-struct ToggleFullScreenData {
-    ns_window: id,
-    ns_view: id,
-    not_fullscreen: bool,
-    shared_state: Weak<Mutex<SharedState>>,
-}
-impl ToggleFullScreenData {
-    fn new_ptr(
-        ns_window: id,
-        ns_view: id,
-        not_fullscreen: bool,
-        shared_state: Weak<Mutex<SharedState>>,
-    ) -> *mut Self {
-        Box::into_raw(Box::new(ToggleFullScreenData {
-            ns_window,
-            ns_view,
-            not_fullscreen,
-            shared_state,
-        }))
-    }
-}
-extern "C" fn toggle_full_screen_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut ToggleFullScreenData;
-        {
-            let context = &*context_ptr;
-
-            // `toggleFullScreen` doesn't work if the `StyleMask` is none, so we
-            // set a normal style temporarily. The previous state will be
-            // restored in `WindowDelegate::window_did_exit_fullscreen`.
-            if context.not_fullscreen {
-                let curr_mask = context.ns_window.styleMask();
-                let required = NSWindowStyleMask::NSTitledWindowMask
-                    | NSWindowStyleMask::NSResizableWindowMask;
-                if !curr_mask.contains(required) {
-                    set_style_mask(context.ns_window, context.ns_view, required);
-                    if let Some(shared_state) = context.shared_state.upgrade() {
-                        trace!("Locked shared state in `toggle_full_screen_callback`");
-                        let mut shared_state_lock = shared_state.lock().unwrap();
-                        (*shared_state_lock).saved_style = Some(curr_mask);
-                        trace!("Unlocked shared state in `toggle_full_screen_callback`");
-                    }
-                }
-            }
-            // Window level must be restored from `CGShieldingWindowLevel()
-            // + 1` back to normal in order for `toggleFullScreen` to do
-            // anything
-            context.ns_window.setLevel_(0);
-            context.ns_window.toggleFullScreen_(nil);
-        }
-        Box::from_raw(context_ptr);
-    }
-}
 // `toggleFullScreen` is thread-safe, but our additional logic to account for
 // window styles isn't.
 pub unsafe fn toggle_full_screen_async(
@@ -227,91 +95,42 @@ pub unsafe fn toggle_full_screen_async(
     not_fullscreen: bool,
     shared_state: Weak<Mutex<SharedState>>,
 ) {
-    let context = ToggleFullScreenData::new_ptr(ns_window, ns_view, not_fullscreen, shared_state);
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        context as *mut _,
-        toggle_full_screen_callback,
-    );
-}
-
-extern "C" fn restore_display_mode_callback(screen: *mut c_void) {
-    unsafe {
-        let screen = Box::from_raw(screen as *mut u32);
-        ffi::CGRestorePermanentDisplayConfiguration();
-        assert_eq!(ffi::CGDisplayRelease(*screen), ffi::kCGErrorSuccess);
-    }
-}
-pub unsafe fn restore_display_mode_async(ns_screen: u32) {
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        Box::into_raw(Box::new(ns_screen)) as *mut _,
-        restore_display_mode_callback,
-    );
-}
-
-struct SetMaximizedData {
-    ns_window: id,
-    is_zoomed: bool,
-    maximized: bool,
-    shared_state: Weak<Mutex<SharedState>>,
-}
-impl SetMaximizedData {
-    fn new_ptr(
-        ns_window: id,
-        is_zoomed: bool,
-        maximized: bool,
-        shared_state: Weak<Mutex<SharedState>>,
-    ) -> *mut Self {
-        Box::into_raw(Box::new(SetMaximizedData {
-            ns_window,
-            is_zoomed,
-            maximized,
-            shared_state,
-        }))
-    }
-}
-extern "C" fn set_maximized_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut SetMaximizedData;
-        {
-            let context = &*context_ptr;
-
-            if let Some(shared_state) = context.shared_state.upgrade() {
-                trace!("Locked shared state in `set_maximized`");
-                let mut shared_state_lock = shared_state.lock().unwrap();
-
-                // Save the standard frame sized if it is not zoomed
-                if !context.is_zoomed {
-                    shared_state_lock.standard_frame = Some(NSWindow::frame(context.ns_window));
+    let ns_window = MainThreadSafe(ns_window);
+    let ns_view = MainThreadSafe(ns_view);
+    let shared_state = MainThreadSafe(shared_state);
+    Queue::main().exec_async(move || {
+        // `toggleFullScreen` doesn't work if the `StyleMask` is none, so we
+        // set a normal style temporarily. The previous state will be
+        // restored in `WindowDelegate::window_did_exit_fullscreen`.
+        if not_fullscreen {
+            let curr_mask = ns_window.styleMask();
+            let required =
+                NSWindowStyleMask::NSTitledWindowMask | NSWindowStyleMask::NSResizableWindowMask;
+            if !curr_mask.contains(required) {
+                set_style_mask(*ns_window, *ns_view, required);
+                if let Some(shared_state) = shared_state.upgrade() {
+                    trace!("Locked shared state in `toggle_full_screen_callback`");
+                    let mut shared_state_lock = shared_state.lock().unwrap();
+                    (*shared_state_lock).saved_style = Some(curr_mask);
+                    trace!("Unlocked shared state in `toggle_full_screen_callback`");
                 }
-
-                shared_state_lock.maximized = context.maximized;
-
-                let curr_mask = context.ns_window.styleMask();
-                if shared_state_lock.fullscreen.is_some() {
-                    // Handle it in window_did_exit_fullscreen
-                    return;
-                } else if curr_mask.contains(NSWindowStyleMask::NSResizableWindowMask) {
-                    // Just use the native zoom if resizable
-                    context.ns_window.zoom_(nil);
-                } else {
-                    // if it's not resizable, we set the frame directly
-                    let new_rect = if context.maximized {
-                        let screen = NSScreen::mainScreen(nil);
-                        NSScreen::visibleFrame(screen)
-                    } else {
-                        shared_state_lock.saved_standard_frame()
-                    };
-                    context.ns_window.setFrame_display_(new_rect, 0);
-                }
-
-                trace!("Unlocked shared state in `set_maximized`");
             }
         }
-        Box::from_raw(context_ptr);
-    }
+        // Window level must be restored from `CGShieldingWindowLevel()
+        // + 1` back to normal in order for `toggleFullScreen` to do
+        // anything
+        ns_window.setLevel_(0);
+        ns_window.toggleFullScreen_(nil);
+    });
 }
+
+pub unsafe fn restore_display_mode_async(ns_screen: u32) {
+    Queue::main().exec_async(move || {
+        ffi::CGRestorePermanentDisplayConfiguration();
+        assert_eq!(ffi::CGDisplayRelease(ns_screen), ffi::kCGErrorSuccess);
+    });
+}
+
 // `setMaximized` is not thread-safe
 pub unsafe fn set_maximized_async(
     ns_window: id,
@@ -319,127 +138,79 @@ pub unsafe fn set_maximized_async(
     maximized: bool,
     shared_state: Weak<Mutex<SharedState>>,
 ) {
-    let context = SetMaximizedData::new_ptr(ns_window, is_zoomed, maximized, shared_state);
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        context as *mut _,
-        set_maximized_callback,
-    );
+    let ns_window = MainThreadSafe(ns_window);
+    let shared_state = MainThreadSafe(shared_state);
+    Queue::main().exec_async(move || {
+        if let Some(shared_state) = shared_state.upgrade() {
+            trace!("Locked shared state in `set_maximized`");
+            let mut shared_state_lock = shared_state.lock().unwrap();
+
+            // Save the standard frame sized if it is not zoomed
+            if !is_zoomed {
+                shared_state_lock.standard_frame = Some(NSWindow::frame(*ns_window));
+            }
+
+            shared_state_lock.maximized = maximized;
+
+            let curr_mask = ns_window.styleMask();
+            if shared_state_lock.fullscreen.is_some() {
+                // Handle it in window_did_exit_fullscreen
+                return;
+            } else if curr_mask.contains(NSWindowStyleMask::NSResizableWindowMask) {
+                // Just use the native zoom if resizable
+                ns_window.zoom_(nil);
+            } else {
+                // if it's not resizable, we set the frame directly
+                let new_rect = if maximized {
+                    let screen = NSScreen::mainScreen(nil);
+                    NSScreen::visibleFrame(screen)
+                } else {
+                    shared_state_lock.saved_standard_frame()
+                };
+                ns_window.setFrame_display_(new_rect, 0);
+            }
+
+            trace!("Unlocked shared state in `set_maximized`");
+        }
+    });
 }
 
-struct OrderOutData {
-    ns_window: id,
-}
-impl OrderOutData {
-    fn new_ptr(ns_window: id) -> *mut Self {
-        Box::into_raw(Box::new(OrderOutData { ns_window }))
-    }
-}
-extern "C" fn order_out_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut OrderOutData;
-        {
-            let context = &*context_ptr;
-            context.ns_window.orderOut_(nil);
-        }
-        Box::from_raw(context_ptr);
-    }
-}
 // `orderOut:` isn't thread-safe. Calling it from another thread actually works,
 // but with an odd delay.
 pub unsafe fn order_out_async(ns_window: id) {
-    let context = OrderOutData::new_ptr(ns_window);
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        context as *mut _,
-        order_out_callback,
-    );
+    let ns_window = MainThreadSafe(ns_window);
+    Queue::main().exec_async(move || {
+        ns_window.orderOut_(nil);
+    });
 }
 
-struct MakeKeyAndOrderFrontData {
-    ns_window: id,
-}
-impl MakeKeyAndOrderFrontData {
-    fn new_ptr(ns_window: id) -> *mut Self {
-        Box::into_raw(Box::new(MakeKeyAndOrderFrontData { ns_window }))
-    }
-}
-extern "C" fn make_key_and_order_front_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut MakeKeyAndOrderFrontData;
-        {
-            let context = &*context_ptr;
-            context.ns_window.makeKeyAndOrderFront_(nil);
-        }
-        Box::from_raw(context_ptr);
-    }
-}
 // `makeKeyAndOrderFront:` isn't thread-safe. Calling it from another thread
 // actually works, but with an odd delay.
 pub unsafe fn make_key_and_order_front_async(ns_window: id) {
-    let context = MakeKeyAndOrderFrontData::new_ptr(ns_window);
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        context as *mut _,
-        make_key_and_order_front_callback,
-    );
+    let ns_window = MainThreadSafe(ns_window);
+    Queue::main().exec_async(move || {
+        ns_window.makeKeyAndOrderFront_(nil);
+    });
 }
 
-struct SetTitleData {
-    ns_window: id,
-    title: String,
-}
-impl SetTitleData {
-    fn new_ptr(ns_window: id, title: String) -> *mut Self {
-        Box::into_raw(Box::new(SetTitleData { ns_window, title }))
-    }
-}
-extern "C" fn set_title_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut SetTitleData;
-        {
-            let context = &*context_ptr;
-            let title = IdRef::new(NSString::alloc(nil).init_str(&context.title));
-            context.ns_window.setTitle_(*title);
-        }
-        Box::from_raw(context_ptr);
-    }
-}
 // `setTitle:` isn't thread-safe. Calling it from another thread invalidates the
 // window drag regions, which throws an exception when not done in the main
 // thread
 pub unsafe fn set_title_async(ns_window: id, title: String) {
-    let context = SetTitleData::new_ptr(ns_window, title);
-    dispatch_async_f(
-        dispatch_get_main_queue(),
-        context as *mut _,
-        set_title_callback,
-    );
+    let ns_window = MainThreadSafe(ns_window);
+    Queue::main().exec_async(move || {
+        let title = IdRef::new(NSString::alloc(nil).init_str(&title));
+        ns_window.setTitle_(*title);
+    });
 }
 
-struct CloseData {
-    ns_window: id,
-}
-impl CloseData {
-    fn new_ptr(ns_window: id) -> *mut Self {
-        Box::into_raw(Box::new(CloseData { ns_window }))
-    }
-}
-extern "C" fn close_callback(context: *mut c_void) {
-    unsafe {
-        let context_ptr = context as *mut CloseData;
-        {
-            let context = &*context_ptr;
-            let pool = NSAutoreleasePool::new(nil);
-            context.ns_window.close();
-            pool.drain();
-        }
-        Box::from_raw(context_ptr);
-    }
-}
 // `close:` is thread-safe, but we want the event to be triggered from the main
 // thread. Though, it's a good idea to look into that more...
 pub unsafe fn close_async(ns_window: id) {
-    let context = CloseData::new_ptr(ns_window);
-    dispatch_async_f(dispatch_get_main_queue(), context as *mut _, close_callback);
+    let ns_window = MainThreadSafe(ns_window);
+    Queue::main().exec_async(move || {
+        autoreleasepool(move || {
+            ns_window.close();
+        });
+    });
 }

src/platform_impl/macos/util/mod.rs

@@ -8,7 +8,7 @@ use std::ops::{BitAnd, Deref};
 use cocoa::{
     appkit::{NSApp, NSWindowStyleMask},
     base::{id, nil},
-    foundation::{NSAutoreleasePool, NSRect, NSUInteger},
+    foundation::{NSAutoreleasePool, NSRect, NSString, NSUInteger},
 };
 use core_graphics::display::CGDisplay;
 use objc::runtime::{Class, Object, Sel, BOOL, YES};
@@ -31,6 +31,7 @@ pub const EMPTY_RANGE: ffi::NSRange = ffi::NSRange {
     length: 0,
 };
 
+#[derive(Debug, PartialEq)]
 pub struct IdRef(id);
 
 impl IdRef {
@@ -90,6 +91,22 @@ pub fn bottom_left_to_top_left(rect: NSRect) -> f64 {
     CGDisplay::main().pixels_high() as f64 - (rect.origin.y + rect.size.height)
 }
 
+pub unsafe fn ns_string_id_ref(s: &str) -> IdRef {
+    IdRef::new(NSString::alloc(nil).init_str(s))
+}
+
+pub unsafe fn app_name() -> Option<id> {
+    let bundle: id = msg_send![class!(NSBundle), mainBundle];
+    let dict: id = msg_send![bundle, infoDictionary];
+    let key = ns_string_id_ref("CFBundleName");
+    let app_name: id = msg_send![dict, objectForKey:*key];
+    if app_name != nil {
+        Some(app_name)
+    } else {
+        None
+    }
+}
+
 pub unsafe fn superclass<'a>(this: &'a Object) -> &'a Class {
     let superclass: id = msg_send![this, superclass];
     &*(superclass as *const _)

src/platform_impl/macos/view.rs

@@ -17,6 +17,7 @@ use objc::{
 };
 
 use crate::{
+    dpi::LogicalPosition,
     event::{
         DeviceEvent, ElementState, Event, KeyboardInput, ModifiersState, MouseButton,
         MouseScrollDelta, TouchPhase, VirtualKeyCode, WindowEvent,
@@ -25,7 +26,7 @@ use crate::{
         app_state::AppState,
         event::{
             char_to_keycode, check_function_keys, event_mods, get_scancode, modifier_event,
-            scancode_to_keycode,
+            scancode_to_keycode, EventWrapper,
         },
         ffi::*,
         util::{self, IdRef},
@@ -49,16 +50,22 @@ impl Default for CursorState {
     }
 }
 
-struct ViewState {
+pub(super) struct ViewState {
     ns_window: id,
     pub cursor_state: Arc<Mutex<CursorState>>,
     ime_spot: Option<(f64, f64)>,
     raw_characters: Option<String>,
     is_key_down: bool,
-    modifiers: ModifiersState,
+    pub(super) modifiers: ModifiersState,
     tracking_rect: Option<NSInteger>,
 }
 
+impl ViewState {
+    fn get_scale_factor(&self) -> f64 {
+        (unsafe { NSWindow::backingScaleFactor(self.ns_window) }) as f64
+    }
+}
+
 pub fn new_view(ns_window: id) -> (IdRef, Weak<Mutex<CursorState>>) {
     let cursor_state = Default::default();
     let cursor_access = Arc::downgrade(&cursor_state);
@@ -512,10 +519,10 @@ extern "C" fn insert_text(this: &Object, _sel: Sel, string: id, _replacement_ran
 
         let mut events = VecDeque::with_capacity(characters.len());
         for character in string.chars().filter(|c| !is_corporate_character(*c)) {
-            events.push_back(Event::WindowEvent {
+            events.push_back(EventWrapper::StaticEvent(Event::WindowEvent {
                 window_id: WindowId(get_window_id(state.ns_window)),
                 event: WindowEvent::ReceivedCharacter(character),
-            });
+            }));
         }
 
         AppState::queue_events(events);
@@ -536,10 +543,10 @@ extern "C" fn do_command_by_selector(this: &Object, _sel: Sel, command: Sel) {
             // The `else` condition would emit the same character, but I'm keeping this here both...
             // 1) as a reminder for how `doCommandBySelector` works
             // 2) to make our use of carriage return explicit
-            events.push_back(Event::WindowEvent {
+            events.push_back(EventWrapper::StaticEvent(Event::WindowEvent {
                 window_id: WindowId(get_window_id(state.ns_window)),
                 event: WindowEvent::ReceivedCharacter('\r'),
-            });
+            }));
         } else {
             let raw_characters = state.raw_characters.take();
             if let Some(raw_characters) = raw_characters {
@@ -547,10 +554,10 @@ extern "C" fn do_command_by_selector(this: &Object, _sel: Sel, command: Sel) {
                     .chars()
                     .filter(|c| !is_corporate_character(*c))
                 {
-                    events.push_back(Event::WindowEvent {
+                    events.push_back(EventWrapper::StaticEvent(Event::WindowEvent {
                         window_id: WindowId(get_window_id(state.ns_window)),
                         event: WindowEvent::ReceivedCharacter(character),
-                    });
+                    }));
                 }
             }
         };
@@ -616,6 +623,19 @@ fn retrieve_keycode(event: id) -> Option<VirtualKeyCode> {
     })
 }
 
+// Update `state.modifiers` if `event` has something different
+fn update_potentially_stale_modifiers(state: &mut ViewState, event: id) {
+    let event_modifiers = event_mods(event);
+    if state.modifiers != event_modifiers {
+        state.modifiers = event_modifiers;
+
+        AppState::queue_event(EventWrapper::StaticEvent(Event::WindowEvent {
+            window_id: WindowId(get_window_id(state.ns_window)),
+            event: WindowEvent::ModifiersChanged(state.modifiers),
+        }));
+    }
+}
+
 extern "C" fn key_down(this: &Object, _sel: Sel, event: id) {
     trace!("Triggered `keyDown`");
     unsafe {
@@ -631,6 +651,9 @@ extern "C" fn key_down(this: &Object, _sel: Sel, event: id) {
 
         let is_repeat = msg_send![event, isARepeat];
 
+        update_potentially_stale_modifiers(state, event);
+
+        #[allow(deprecated)]
         let window_event = Event::WindowEvent {
             window_id,
             event: WindowEvent::KeyboardInput {
@@ -646,14 +669,14 @@ extern "C" fn key_down(this: &Object, _sel: Sel, event: id) {
         };
 
         let pass_along = {
-            AppState::queue_event(window_event);
+            AppState::queue_event(EventWrapper::StaticEvent(window_event));
             // Emit `ReceivedCharacter` for key repeats
             if is_repeat && state.is_key_down {
                 for character in characters.chars().filter(|c| !is_corporate_character(*c)) {
-                    AppState::queue_event(Event::WindowEvent {
+                    AppState::queue_event(EventWrapper::StaticEvent(Event::WindowEvent {
                         window_id,
                         event: WindowEvent::ReceivedCharacter(character),
-                    });
+                    }));
                 }
                 false
             } else {
@@ -683,6 +706,9 @@ extern "C" fn key_up(this: &Object, _sel: Sel, event: id) {
         let scancode = get_scancode(event) as u32;
         let virtual_keycode = retrieve_keycode(event);
 
+        update_potentially_stale_modifiers(state, event);
+
+        #[allow(deprecated)]
         let window_event = Event::WindowEvent {
             window_id: WindowId(get_window_id(state.ns_window)),
             event: WindowEvent::KeyboardInput {
@@ -697,7 +723,7 @@ extern "C" fn key_up(this: &Object, _sel: Sel, event: id) {
             },
         };
 
-        AppState::queue_event(window_event);
+        AppState::queue_event(EventWrapper::StaticEvent(window_event));
     }
     trace!("Completed `keyUp`");
 }
@@ -746,17 +772,19 @@ extern "C" fn flags_changed(this: &Object, _sel: Sel, event: id) {
             events.push_back(window_event);
         }
 
+        let window_id = WindowId(get_window_id(state.ns_window));
+
         for event in events {
-            AppState::queue_event(Event::WindowEvent {
-                window_id: WindowId(get_window_id(state.ns_window)),
+            AppState::queue_event(EventWrapper::StaticEvent(Event::WindowEvent {
+                window_id,
                 event,
-            });
+            }));
         }
 
-        AppState::queue_event(Event::DeviceEvent {
-            device_id: DEVICE_ID,
-            event: DeviceEvent::ModifiersChanged(state.modifiers),
-        });
+        AppState::queue_event(EventWrapper::StaticEvent(Event::WindowEvent {
+            window_id,
+            event: WindowEvent::ModifiersChanged(state.modifiers),
+        }));
     }
     trace!("Completed `flagsChanged`");
 }
@@ -797,6 +825,9 @@ extern "C" fn cancel_operation(this: &Object, _sel: Sel, _sender: id) {
 
         let event: id = msg_send![NSApp(), currentEvent];
 
+        update_potentially_stale_modifiers(state, event);
+
+        #[allow(deprecated)]
         let window_event = Event::WindowEvent {
             window_id: WindowId(get_window_id(state.ns_window)),
             event: WindowEvent::KeyboardInput {
@@ -811,7 +842,7 @@ extern "C" fn cancel_operation(this: &Object, _sel: Sel, _sender: id) {
             },
         };
 
-        AppState::queue_event(window_event);
+        AppState::queue_event(EventWrapper::StaticEvent(window_event));
     }
     trace!("Completed `cancelOperation`");
 }
@@ -821,6 +852,8 @@ fn mouse_click(this: &Object, event: id, button: MouseButton, button_state: Elem
         let state_ptr: *mut c_void = *this.get_ivar("winitState");
         let state = &mut *(state_ptr as *mut ViewState);
 
+        update_potentially_stale_modifiers(state, event);
+
         let window_event = Event::WindowEvent {
             window_id: WindowId(get_window_id(state.ns_window)),
             event: WindowEvent::MouseInput {
@@ -831,7 +864,7 @@ fn mouse_click(this: &Object, event: id, button: MouseButton, button_state: Elem
             },
         };
 
-        AppState::queue_event(window_event);
+        AppState::queue_event(EventWrapper::StaticEvent(window_event));
     }
 }
 
@@ -882,17 +915,20 @@ fn mouse_motion(this: &Object, event: id) {
 
         let x = view_point.x as f64;
         let y = view_rect.size.height as f64 - view_point.y as f64;
+        let logical_position = LogicalPosition::new(x, y);
+
+        update_potentially_stale_modifiers(state, event);
 
         let window_event = Event::WindowEvent {
             window_id: WindowId(get_window_id(state.ns_window)),
             event: WindowEvent::CursorMoved {
                 device_id: DEVICE_ID,
-                position: (x, y).into(),
+                position: logical_position.to_physical(state.get_scale_factor()),
                 modifiers: event_mods(event),
             },
         };
 
-        AppState::queue_event(window_event);
+        AppState::queue_event(EventWrapper::StaticEvent(window_event));
     }
 }
 
@@ -912,7 +948,7 @@ extern "C" fn other_mouse_dragged(this: &Object, _sel: Sel, event: id) {
     mouse_motion(this, event);
 }
 
-extern "C" fn mouse_entered(this: &Object, _sel: Sel, event: id) {
+extern "C" fn mouse_entered(this: &Object, _sel: Sel, _event: id) {
     trace!("Triggered `mouseEntered`");
     unsafe {
         let state_ptr: *mut c_void = *this.get_ivar("winitState");
@@ -925,27 +961,7 @@ extern "C" fn mouse_entered(this: &Object, _sel: Sel, event: id) {
             },
         };
 
-        let move_event = {
-            let window_point = event.locationInWindow();
-            let view_point: NSPoint = msg_send![this,
-                convertPoint:window_point
-                fromView:nil // convert from window coordinates
-            ];
-            let view_rect: NSRect = msg_send![this, frame];
-            let x = view_point.x as f64;
-            let y = (view_rect.size.height - view_point.y) as f64;
-            Event::WindowEvent {
-                window_id: WindowId(get_window_id(state.ns_window)),
-                event: WindowEvent::CursorMoved {
-                    device_id: DEVICE_ID,
-                    position: (x, y).into(),
-                    modifiers: event_mods(event),
-                },
-            }
-        };
-
-        AppState::queue_event(enter_event);
-        AppState::queue_event(move_event);
+        AppState::queue_event(EventWrapper::StaticEvent(enter_event));
     }
     trace!("Completed `mouseEntered`");
 }
@@ -963,7 +979,7 @@ extern "C" fn mouse_exited(this: &Object, _sel: Sel, _event: id) {
             },
         };
 
-        AppState::queue_event(window_event);
+        AppState::queue_event(EventWrapper::StaticEvent(window_event));
     }
     trace!("Completed `mouseExited`");
 }
@@ -995,6 +1011,8 @@ extern "C" fn scroll_wheel(this: &Object, _sel: Sel, event: id) {
         let state_ptr: *mut c_void = *this.get_ivar("winitState");
         let state = &mut *(state_ptr as *mut ViewState);
 
+        update_potentially_stale_modifiers(state, event);
+
         let window_event = Event::WindowEvent {
             window_id: WindowId(get_window_id(state.ns_window)),
             event: WindowEvent::MouseWheel {
@@ -1005,8 +1023,8 @@ extern "C" fn scroll_wheel(this: &Object, _sel: Sel, event: id) {
             },
         };
 
-        AppState::queue_event(device_event);
-        AppState::queue_event(window_event);
+        AppState::queue_event(EventWrapper::StaticEvent(device_event));
+        AppState::queue_event(EventWrapper::StaticEvent(window_event));
     }
     trace!("Completed `scrollWheel`");
 }
@@ -1029,7 +1047,7 @@ extern "C" fn pressure_change_with_event(this: &Object, _sel: Sel, event: id) {
             },
         };
 
-        AppState::queue_event(window_event);
+        AppState::queue_event(EventWrapper::StaticEvent(window_event));
     }
     trace!("Completed `pressureChangeWithEvent`");
 }

src/platform_impl/macos/window.rs

@@ -10,7 +10,9 @@ use std::{
 };
 
 use crate::{
-    dpi::{LogicalPosition, LogicalSize},
+    dpi::{
+        LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize, Position, Size, Size::Logical,
+    },
     error::{ExternalError, NotSupportedError, OsError as RootOsError},
     icon::Icon,
     monitor::{MonitorHandle as RootMonitorHandle, VideoMode as RootVideoMode},
@@ -34,7 +36,7 @@ use cocoa::{
         NSWindow, NSWindowButton, NSWindowStyleMask,
     },
     base::{id, nil},
-    foundation::{NSAutoreleasePool, NSDictionary, NSPoint, NSRect, NSSize, NSString},
+    foundation::{NSAutoreleasePool, NSDictionary, NSPoint, NSRect, NSSize},
 };
 use core_graphics::display::{CGDisplay, CGDisplayMode};
 use objc::{
@@ -66,7 +68,7 @@ pub struct PlatformSpecificWindowBuilderAttributes {
     pub titlebar_hidden: bool,
     pub titlebar_buttons_hidden: bool,
     pub fullsize_content_view: bool,
-    pub resize_increments: Option<LogicalSize>,
+    pub resize_increments: Option<LogicalSize<f64>>,
     pub disallow_hidpi: bool,
 }
 
@@ -130,12 +132,17 @@ fn create_window(
             None => None,
         };
         let frame = match screen {
-            Some(screen) => appkit::NSScreen::frame(screen),
+            Some(screen) => NSScreen::frame(screen),
             None => {
-                let (width, height) = attrs
-                    .inner_size
-                    .map(|logical| (logical.width, logical.height))
-                    .unwrap_or_else(|| (800.0, 600.0));
+                let screen = NSScreen::mainScreen(nil);
+                let scale_factor = NSScreen::backingScaleFactor(screen) as f64;
+                let (width, height) = match attrs.inner_size {
+                    Some(size) => {
+                        let logical = size.to_logical(scale_factor);
+                        (logical.width, logical.height)
+                    }
+                    None => (800.0, 600.0),
+                };
                 NSRect::new(NSPoint::new(0.0, 0.0), NSSize::new(width, height))
             }
         };
@@ -143,10 +150,14 @@ fn create_window(
         let mut masks = if !attrs.decorations && !screen.is_some() {
             // Resizable UnownedWindow without a titlebar or borders
             // if decorations is set to false, ignore pl_attrs
-            NSWindowStyleMask::NSBorderlessWindowMask | NSWindowStyleMask::NSResizableWindowMask
+            NSWindowStyleMask::NSBorderlessWindowMask
+                | NSWindowStyleMask::NSResizableWindowMask
+                | NSWindowStyleMask::NSMiniaturizableWindowMask
         } else if pl_attrs.titlebar_hidden {
             // if the titlebar is hidden, ignore other pl_attrs
-            NSWindowStyleMask::NSBorderlessWindowMask | NSWindowStyleMask::NSResizableWindowMask
+            NSWindowStyleMask::NSBorderlessWindowMask
+                | NSWindowStyleMask::NSResizableWindowMask
+                | NSWindowStyleMask::NSMiniaturizableWindowMask
         } else {
             // default case, resizable window with titlebar and titlebar buttons
             NSWindowStyleMask::NSClosableWindowMask
@@ -171,7 +182,7 @@ fn create_window(
             NO,
         ));
         let res = ns_window.non_nil().map(|ns_window| {
-            let title = IdRef::new(NSString::alloc(nil).init_str(&attrs.title));
+            let title = util::ns_string_id_ref(&attrs.title);
             ns_window.setReleasedWhenClosed_(NO);
             ns_window.setTitle_(*title);
             ns_window.setAcceptsMouseMovedEvents_(YES);
@@ -292,6 +303,7 @@ pub struct UnownedWindow {
     pub shared_state: Arc<Mutex<SharedState>>,
     decorations: AtomicBool,
     cursor_state: Weak<Mutex<CursorState>>,
+    pub inner_rect: Option<PhysicalSize<u32>>,
 }
 
 unsafe impl Send for UnownedWindow {}
@@ -328,6 +340,8 @@ impl UnownedWindow {
 
         let input_context = unsafe { util::create_input_context(*ns_view) };
 
+        let scale_factor = unsafe { NSWindow::backingScaleFactor(*ns_window) as f64 };
+
         unsafe {
             if win_attribs.transparent {
                 ns_window.setOpaque_(NO);
@@ -335,13 +349,14 @@ impl UnownedWindow {
             }
 
             ns_app.activateIgnoringOtherApps_(YES);
-
-            win_attribs
-                .min_inner_size
-                .map(|dim| set_min_inner_size(*ns_window, dim));
-            win_attribs
-                .max_inner_size
-                .map(|dim| set_max_inner_size(*ns_window, dim));
+            win_attribs.min_inner_size.map(|dim| {
+                let logical_dim = dim.to_logical(scale_factor);
+                set_min_inner_size(*ns_window, logical_dim)
+            });
+            win_attribs.max_inner_size.map(|dim| {
+                let logical_dim = dim.to_logical(scale_factor);
+                set_max_inner_size(*ns_window, logical_dim)
+            });
 
             use cocoa::foundation::NSArray;
             // register for drag and drop operations.
@@ -361,6 +376,9 @@ impl UnownedWindow {
         let maximized = win_attribs.maximized;
         let visible = win_attribs.visible;
         let decorations = win_attribs.decorations;
+        let inner_rect = win_attribs
+            .inner_size
+            .map(|size| size.to_physical(scale_factor));
 
         let window = Arc::new(UnownedWindow {
             ns_view,
@@ -369,6 +387,7 @@ impl UnownedWindow {
             shared_state: Arc::new(Mutex::new(win_attribs.into())),
             decorations: AtomicBool::new(decorations),
             cursor_state,
+            inner_rect,
         });
 
         let delegate = new_delegate(&window, fullscreen.is_some());
@@ -425,27 +444,31 @@ impl UnownedWindow {
         AppState::queue_redraw(RootWindowId(self.id()));
     }
 
-    pub fn outer_position(&self) -> Result<LogicalPosition, NotSupportedError> {
+    pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         let frame_rect = unsafe { NSWindow::frame(*self.ns_window) };
-        Ok((
+        let position = LogicalPosition::new(
             frame_rect.origin.x as f64,
             util::bottom_left_to_top_left(frame_rect),
-        )
-            .into())
+        );
+        let scale_factor = self.scale_factor();
+        Ok(position.to_physical(scale_factor))
     }
 
-    pub fn inner_position(&self) -> Result<LogicalPosition, NotSupportedError> {
+    pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
         let content_rect = unsafe {
             NSWindow::contentRectForFrameRect_(*self.ns_window, NSWindow::frame(*self.ns_window))
         };
-        Ok((
+        let position = LogicalPosition::new(
             content_rect.origin.x as f64,
             util::bottom_left_to_top_left(content_rect),
-        )
-            .into())
+        );
+        let scale_factor = self.scale_factor();
+        Ok(position.to_physical(scale_factor))
     }
 
-    pub fn set_outer_position(&self, position: LogicalPosition) {
+    pub fn set_outer_position(&self, position: Position) {
+        let scale_factor = self.scale_factor();
+        let position = position.to_logical(scale_factor);
         let dummy = NSRect::new(
             NSPoint::new(
                 position.x,
@@ -461,35 +484,50 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn inner_size(&self) -> LogicalSize {
+    pub fn inner_size(&self) -> PhysicalSize<u32> {
         let view_frame = unsafe { NSView::frame(*self.ns_view) };
-        (view_frame.size.width as f64, view_frame.size.height as f64).into()
+        let logical: LogicalSize<f64> =
+            (view_frame.size.width as f64, view_frame.size.height as f64).into();
+        let scale_factor = self.scale_factor();
+        logical.to_physical(scale_factor)
     }
 
     #[inline]
-    pub fn outer_size(&self) -> LogicalSize {
+    pub fn outer_size(&self) -> PhysicalSize<u32> {
         let view_frame = unsafe { NSWindow::frame(*self.ns_window) };
-        (view_frame.size.width as f64, view_frame.size.height as f64).into()
+        let logical: LogicalSize<f64> =
+            (view_frame.size.width as f64, view_frame.size.height as f64).into();
+        let scale_factor = self.scale_factor();
+        logical.to_physical(scale_factor)
     }
 
     #[inline]
-    pub fn set_inner_size(&self, size: LogicalSize) {
+    pub fn set_inner_size(&self, size: Size) {
         unsafe {
-            util::set_content_size_async(*self.ns_window, size);
+            let scale_factor = self.scale_factor();
+            util::set_content_size_async(*self.ns_window, size.to_logical(scale_factor));
         }
     }
 
-    pub fn set_min_inner_size(&self, dimensions: Option<LogicalSize>) {
+    pub fn set_min_inner_size(&self, dimensions: Option<Size>) {
         unsafe {
-            let dimensions = dimensions.unwrap_or_else(|| (0, 0).into());
-            set_min_inner_size(*self.ns_window, dimensions);
+            let dimensions = dimensions.unwrap_or(Logical(LogicalSize {
+                width: 0.0,
+                height: 0.0,
+            }));
+            let scale_factor = self.scale_factor();
+            set_min_inner_size(*self.ns_window, dimensions.to_logical(scale_factor));
         }
     }
 
-    pub fn set_max_inner_size(&self, dimensions: Option<LogicalSize>) {
+    pub fn set_max_inner_size(&self, dimensions: Option<Size>) {
         unsafe {
-            let dimensions = dimensions.unwrap_or_else(|| (!0, !0).into());
-            set_max_inner_size(*self.ns_window, dimensions);
+            let dimensions = dimensions.unwrap_or(Logical(LogicalSize {
+                width: std::f32::MAX as f64,
+                height: std::f32::MAX as f64,
+            }));
+            let scale_factor = self.scale_factor();
+            set_max_inner_size(*self.ns_window, dimensions.to_logical(scale_factor));
         }
     }
 
@@ -549,19 +587,19 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f64 {
+    pub fn scale_factor(&self) -> f64 {
         unsafe { NSWindow::backingScaleFactor(*self.ns_window) as _ }
     }
 
     #[inline]
-    pub fn set_cursor_position(
-        &self,
-        cursor_position: LogicalPosition,
-    ) -> Result<(), ExternalError> {
-        let window_position = self.inner_position().unwrap();
+    pub fn set_cursor_position(&self, cursor_position: Position) -> Result<(), ExternalError> {
+        let physical_window_position = self.inner_position().unwrap();
+        let scale_factor = self.scale_factor();
+        let window_position = physical_window_position.to_logical::<CGFloat>(scale_factor);
+        let logical_cursor_position = cursor_position.to_logical::<CGFloat>(scale_factor);
         let point = appkit::CGPoint {
-            x: (cursor_position.x + window_position.x) as CGFloat,
-            y: (cursor_position.y + window_position.y) as CGFloat,
+            x: logical_cursor_position.x + window_position.x,
+            y: logical_cursor_position.y + window_position.y,
         };
         CGDisplay::warp_mouse_cursor_position(point)
             .map_err(|e| ExternalError::Os(os_error!(OsError::CGError(e))))?;
@@ -894,7 +932,9 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn set_ime_position(&self, logical_spot: LogicalPosition) {
+    pub fn set_ime_position(&self, spot: Position) {
+        let scale_factor = self.scale_factor();
+        let logical_spot = spot.to_logical(scale_factor);
         unsafe {
             view::set_ime_position(
                 *self.ns_view,
@@ -910,7 +950,7 @@ impl UnownedWindow {
         unsafe {
             let screen: id = msg_send![*self.ns_window, screen];
             let desc = NSScreen::deviceDescription(screen);
-            let key = IdRef::new(NSString::alloc(nil).init_str("NSScreenNumber"));
+            let key = util::ns_string_id_ref("NSScreenNumber");
             let value = NSDictionary::valueForKey_(desc, *key);
             let display_id = msg_send![value, unsignedIntegerValue];
             RootMonitorHandle {
@@ -988,7 +1028,11 @@ impl WindowExtMacOS for UnownedWindow {
 
             if fullscreen {
                 // Remember the original window's settings
-                shared_state_lock.standard_frame = Some(NSWindow::frame(*self.ns_window));
+                // Exclude title bar
+                shared_state_lock.standard_frame = Some(NSWindow::contentRectForFrameRect_(
+                    *self.ns_window,
+                    NSWindow::frame(*self.ns_window),
+                ));
                 shared_state_lock.saved_style = Some(self.ns_window.styleMask());
                 shared_state_lock.save_presentation_opts = Some(app.presentationOptions_());
 
@@ -1059,7 +1103,7 @@ impl Drop for UnownedWindow {
     }
 }
 
-unsafe fn set_min_inner_size<V: NSWindow + Copy>(window: V, mut min_size: LogicalSize) {
+unsafe fn set_min_inner_size<V: NSWindow + Copy>(window: V, mut min_size: LogicalSize<f64>) {
     let mut current_rect = NSWindow::frame(window);
     let content_rect = NSWindow::contentRectForFrameRect_(window, NSWindow::frame(window));
     // Convert from client area size to window size
@@ -1083,7 +1127,7 @@ unsafe fn set_min_inner_size<V: NSWindow + Copy>(window: V, mut min_size: Logica
     }
 }
 
-unsafe fn set_max_inner_size<V: NSWindow + Copy>(window: V, mut max_size: LogicalSize) {
+unsafe fn set_max_inner_size<V: NSWindow + Copy>(window: V, mut max_size: LogicalSize<f64>) {
     let mut current_rect = NSWindow::frame(window);
     let content_rect = NSWindow::contentRectForFrameRect_(window, NSWindow::frame(window));
     // Convert from client area size to window size

src/platform_impl/macos/window_delegate.rs

@@ -16,10 +16,12 @@ use objc::{
 
 use crate::{
     dpi::LogicalSize,
-    event::{Event, WindowEvent},
+    event::{Event, ModifiersState, WindowEvent},
     platform_impl::platform::{
         app_state::AppState,
+        event::{EventProxy, EventWrapper},
         util::{self, IdRef},
+        view::ViewState,
         window::{get_window_id, UnownedWindow},
     },
     window::{Fullscreen, WindowId},
@@ -42,25 +44,23 @@ pub struct WindowDelegateState {
     previous_position: Option<(f64, f64)>,
 
     // Used to prevent redundant events.
-    previous_dpi_factor: f64,
+    previous_scale_factor: f64,
 }
 
 impl WindowDelegateState {
     pub fn new(window: &Arc<UnownedWindow>, initial_fullscreen: bool) -> Self {
-        let dpi_factor = window.hidpi_factor();
-
+        let scale_factor = window.scale_factor();
         let mut delegate_state = WindowDelegateState {
             ns_window: window.ns_window.clone(),
             ns_view: window.ns_view.clone(),
             window: Arc::downgrade(&window),
             initial_fullscreen,
             previous_position: None,
-            previous_dpi_factor: dpi_factor,
+            previous_scale_factor: scale_factor,
         };
 
-        if dpi_factor != 1.0 {
-            delegate_state.emit_event(WindowEvent::HiDpiFactorChanged(dpi_factor));
-            delegate_state.emit_resize_event();
+        if scale_factor != 1.0 {
+            delegate_state.emit_static_scale_factor_changed_event();
         }
 
         delegate_state
@@ -73,17 +73,34 @@ impl WindowDelegateState {
         self.window.upgrade().map(|ref window| callback(window))
     }
 
-    pub fn emit_event(&mut self, event: WindowEvent) {
+    pub fn emit_event(&mut self, event: WindowEvent<'static>) {
         let event = Event::WindowEvent {
             window_id: WindowId(get_window_id(*self.ns_window)),
             event,
         };
-        AppState::queue_event(event);
+        AppState::queue_event(EventWrapper::StaticEvent(event));
+    }
+
+    pub fn emit_static_scale_factor_changed_event(&mut self) {
+        let scale_factor = self.get_scale_factor();
+        if scale_factor == self.previous_scale_factor {
+            return ();
+        };
+
+        self.previous_scale_factor = scale_factor;
+        let wrapper = EventWrapper::EventProxy(EventProxy::DpiChangedProxy {
+            ns_window: IdRef::retain(*self.ns_window),
+            suggested_size: self.view_size(),
+            scale_factor,
+        });
+        AppState::queue_event(wrapper);
     }
 
     pub fn emit_resize_event(&mut self) {
         let rect = unsafe { NSView::frame(*self.ns_view) };
-        let size = LogicalSize::new(rect.size.width as f64, rect.size.height as f64);
+        let scale_factor = self.get_scale_factor();
+        let logical_size = LogicalSize::new(rect.size.width as f64, rect.size.height as f64);
+        let size = logical_size.to_physical(scale_factor);
         self.emit_event(WindowEvent::Resized(size));
     }
 
@@ -97,6 +114,15 @@ impl WindowDelegateState {
             self.emit_event(WindowEvent::Moved((x, y).into()));
         }
     }
+
+    fn get_scale_factor(&self) -> f64 {
+        (unsafe { NSWindow::backingScaleFactor(*self.ns_window) }) as f64
+    }
+
+    fn view_size(&self) -> LogicalSize<f64> {
+        let ns_size = unsafe { NSView::frame(*self.ns_view).size };
+        LogicalSize::new(ns_size.width as f64, ns_size.height as f64)
+    }
 }
 
 pub fn new_delegate(window: &Arc<UnownedWindow>, initial_fullscreen: bool) -> IdRef {
@@ -140,10 +166,6 @@ lazy_static! {
             sel!(windowDidMove:),
             window_did_move as extern "C" fn(&Object, Sel, id),
         );
-        decl.add_method(
-            sel!(windowDidChangeScreen:),
-            window_did_change_screen as extern "C" fn(&Object, Sel, id),
-        );
         decl.add_method(
             sel!(windowDidChangeBackingProperties:),
             window_did_change_backing_properties as extern "C" fn(&Object, Sel, id),
@@ -277,29 +299,10 @@ extern "C" fn window_did_move(this: &Object, _: Sel, _: id) {
     trace!("Completed `windowDidMove:`");
 }
 
-extern "C" fn window_did_change_screen(this: &Object, _: Sel, _: id) {
-    trace!("Triggered `windowDidChangeScreen:`");
-    with_state(this, |state| {
-        let dpi_factor = unsafe { NSWindow::backingScaleFactor(*state.ns_window) } as f64;
-        if state.previous_dpi_factor != dpi_factor {
-            state.previous_dpi_factor = dpi_factor;
-            state.emit_event(WindowEvent::HiDpiFactorChanged(dpi_factor));
-            state.emit_resize_event();
-        }
-    });
-    trace!("Completed `windowDidChangeScreen:`");
-}
-
-// This will always be called before `window_did_change_screen`.
 extern "C" fn window_did_change_backing_properties(this: &Object, _: Sel, _: id) {
     trace!("Triggered `windowDidChangeBackingProperties:`");
     with_state(this, |state| {
-        let dpi_factor = unsafe { NSWindow::backingScaleFactor(*state.ns_window) } as f64;
-        if state.previous_dpi_factor != dpi_factor {
-            state.previous_dpi_factor = dpi_factor;
-            state.emit_event(WindowEvent::HiDpiFactorChanged(dpi_factor));
-            state.emit_resize_event();
-        }
+        state.emit_static_scale_factor_changed_event();
     });
     trace!("Completed `windowDidChangeBackingProperties:`");
 }
@@ -317,6 +320,29 @@ extern "C" fn window_did_become_key(this: &Object, _: Sel, _: id) {
 extern "C" fn window_did_resign_key(this: &Object, _: Sel, _: id) {
     trace!("Triggered `windowDidResignKey:`");
     with_state(this, |state| {
+        // It happens rather often, e.g. when the user is Cmd+Tabbing, that the
+        // NSWindowDelegate will receive a didResignKey event despite no event
+        // being received when the modifiers are released.  This is because
+        // flagsChanged events are received by the NSView instead of the
+        // NSWindowDelegate, and as a result a tracked modifiers state can quite
+        // easily fall out of synchrony with reality.  This requires us to emit
+        // a synthetic ModifiersChanged event when we lose focus.
+        //
+        // Here we (very unsafely) acquire the winitState (a ViewState) from the
+        // Object referenced by state.ns_view (an IdRef, which is dereferenced
+        // to an id)
+        let view_state: &mut ViewState = unsafe {
+            let ns_view: &Object = (*state.ns_view).as_ref().expect("failed to deref");
+            let state_ptr: *mut c_void = *ns_view.get_ivar("winitState");
+            &mut *(state_ptr as *mut ViewState)
+        };
+
+        // Both update the state and emit a ModifiersChanged event.
+        if !view_state.modifiers.is_empty() {
+            view_state.modifiers = ModifiersState::empty();
+            state.emit_event(WindowEvent::ModifiersChanged(view_state.modifiers));
+        }
+
         state.emit_event(WindowEvent::Focused(false));
     });
     trace!("Completed `windowDidResignKey:`");

src/platform_impl/web/event_loop/mod.rs

@@ -37,7 +37,8 @@ impl<T> EventLoop<T> {
 
     pub fn run<F>(self, mut event_handler: F) -> !
     where
-        F: 'static + FnMut(Event<T>, &root::EventLoopWindowTarget<T>, &mut root::ControlFlow),
+        F: 'static
+            + FnMut(Event<'static, T>, &root::EventLoopWindowTarget<T>, &mut root::ControlFlow),
     {
         let target = root::EventLoopWindowTarget {
             p: self.elw.p.clone(),

src/platform_impl/web/event_loop/runner.rs

@@ -8,10 +8,11 @@ use std::{
     cell::RefCell,
     clone::Clone,
     collections::{HashSet, VecDeque},
+    iter,
     rc::Rc,
 };
 
-pub struct Shared<T>(Rc<Execution<T>>);
+pub struct Shared<T: 'static>(Rc<Execution<T>>);
 
 impl<T> Clone for Shared<T> {
     fn clone(&self) -> Self {
@@ -19,21 +20,21 @@ impl<T> Clone for Shared<T> {
     }
 }
 
-pub struct Execution<T> {
+pub struct Execution<T: 'static> {
     runner: RefCell<Option<Runner<T>>>,
-    events: RefCell<VecDeque<Event<T>>>,
+    events: RefCell<VecDeque<Event<'static, T>>>,
     id: RefCell<u32>,
     redraw_pending: RefCell<HashSet<WindowId>>,
 }
 
-struct Runner<T> {
+struct Runner<T: 'static> {
     state: State,
     is_busy: bool,
-    event_handler: Box<dyn FnMut(Event<T>, &mut root::ControlFlow)>,
+    event_handler: Box<dyn FnMut(Event<'static, T>, &mut root::ControlFlow)>,
 }
 
 impl<T: 'static> Runner<T> {
-    pub fn new(event_handler: Box<dyn FnMut(Event<T>, &mut root::ControlFlow)>) -> Self {
+    pub fn new(event_handler: Box<dyn FnMut(Event<'static, T>, &mut root::ControlFlow)>) -> Self {
         Runner {
             state: State::Init,
             is_busy: false,
@@ -55,9 +56,12 @@ impl<T: 'static> Shared<T> {
     // Set the event callback to use for the event loop runner
     // This the event callback is a fairly thin layer over the user-provided callback that closes
     // over a RootEventLoopWindowTarget reference
-    pub fn set_listener(&self, event_handler: Box<dyn FnMut(Event<T>, &mut root::ControlFlow)>) {
+    pub fn set_listener(
+        &self,
+        event_handler: Box<dyn FnMut(Event<'static, T>, &mut root::ControlFlow)>,
+    ) {
         self.0.runner.replace(Some(Runner::new(event_handler)));
-        self.send_event(Event::NewEvents(StartCause::Init));
+        self.init();
 
         let close_instance = self.clone();
         backend::on_unload(move || close_instance.handle_unload());
@@ -76,55 +80,98 @@ impl<T: 'static> Shared<T> {
         self.0.redraw_pending.borrow_mut().insert(id);
     }
 
-    // Add an event to the event loop runner
+    pub fn init(&self) {
+        let start_cause = Event::NewEvents(StartCause::Init);
+        self.run_until_cleared(iter::once(start_cause));
+    }
+
+    // Run the polling logic for the Poll ControlFlow, which involves clearing the queue
+    pub fn poll(&self) {
+        let start_cause = Event::NewEvents(StartCause::Poll);
+        self.run_until_cleared(iter::once(start_cause));
+    }
+
+    // Run the logic for waking from a WaitUntil, which involves clearing the queue
+    // Generally there shouldn't be events built up when this is called
+    pub fn resume_time_reached(&self, start: Instant, requested_resume: Instant) {
+        let start_cause = Event::NewEvents(StartCause::ResumeTimeReached {
+            start,
+            requested_resume,
+        });
+        self.run_until_cleared(iter::once(start_cause));
+    }
+
+    // Add an event to the event loop runner, from the user or an event handler
     //
     // It will determine if the event should be immediately sent to the user or buffered for later
-    pub fn send_event(&self, event: Event<T>) {
+    pub fn send_event(&self, event: Event<'static, T>) {
+        self.send_events(iter::once(event));
+    }
+
+    // Add a series of events to the event loop runner
+    //
+    // It will determine if the event should be immediately sent to the user or buffered for later
+    pub fn send_events(&self, events: impl Iterator<Item = Event<'static, T>>) {
         // If the event loop is closed, it should discard any new events
         if self.is_closed() {
             return;
         }
-
-        // Determine if event handling is in process, and then release the borrow on the runner
-        let (start_cause, event_is_start) = match *self.0.runner.borrow() {
-            Some(ref runner) if !runner.is_busy => {
-                if let Event::NewEvents(cause) = event {
-                    (cause, true)
-                } else {
-                    (
-                        match runner.state {
-                            State::Init => StartCause::Init,
-                            State::Poll { .. } => StartCause::Poll,
-                            State::Wait { start } => StartCause::WaitCancelled {
-                                start,
-                                requested_resume: None,
-                            },
-                            State::WaitUntil { start, end, .. } => StartCause::WaitCancelled {
-                                start,
-                                requested_resume: Some(end),
-                            },
-                            State::Exit => {
-                                return;
-                            }
-                        },
-                        false,
-                    )
+        // If we can run the event processing right now, or need to queue this and wait for later
+        let mut process_immediately = true;
+        if let Some(ref runner) = &*self.0.runner.borrow() {
+            // If we're currently polling, queue this and wait for the poll() method to be called
+            if let State::Poll { .. } = runner.state {
+                process_immediately = false;
+            }
+            // If the runner is busy, queue this and wait for it to process it later
+            if runner.is_busy {
+                process_immediately = false;
+            }
+        } else {
+            // The runner still hasn't been attached: queue this event and wait for it to be
+            process_immediately = false;
+        }
+        if !process_immediately {
+            // Queue these events to look at later
+            self.0.events.borrow_mut().extend(events);
+            return;
+        }
+        // At this point, we know this is a fresh set of events
+        // Now we determine why new events are incoming, and handle the events
+        let start_cause = if let Some(runner) = &*self.0.runner.borrow() {
+            match runner.state {
+                State::Init => StartCause::Init,
+                State::Poll { .. } => StartCause::Poll,
+                State::Wait { start } => StartCause::WaitCancelled {
+                    start,
+                    requested_resume: None,
+                },
+                State::WaitUntil { start, end, .. } => StartCause::WaitCancelled {
+                    start,
+                    requested_resume: Some(end),
+                },
+                State::Exit => {
+                    // If we're in the exit state, don't do event processing
+                    return;
                 }
             }
-            _ => {
-                // Events are currently being handled, so queue this one and don't try to
-                // double-process the event queue
-                self.0.events.borrow_mut().push_back(event);
-                return;
-            }
+        } else {
+            unreachable!("The runner cannot process events when it is not attached");
         };
+        // Take the start event, then the events provided to this function, and run an iteration of
+        // the event loop
+        let start_event = Event::NewEvents(start_cause);
+        let events = iter::once(start_event).chain(events);
+        self.run_until_cleared(events);
+    }
+
+    // Given the set of new events, run the event loop until the main events and redraw events are
+    // cleared
+    //
+    // This will also process any events that have been queued or that are queued during processing
+    fn run_until_cleared(&self, events: impl Iterator<Item = Event<'static, T>>) {
         let mut control = self.current_control_flow();
-        // Handle starting a new batch of events
-        //
-        // The user is informed via Event::NewEvents that there is a batch of events to process
-        // However, there is only one of these per batch of events
-        self.handle_event(Event::NewEvents(start_cause), &mut control);
-        if !event_is_start {
+        for event in events {
             self.handle_event(event, &mut control);
         }
         self.handle_event(Event::MainEventsCleared, &mut control);
@@ -153,7 +200,7 @@ impl<T: 'static> Shared<T> {
     // handle_event takes in events and either queues them or applies a callback
     //
     // It should only ever be called from send_event
-    fn handle_event(&self, event: Event<T>, control: &mut root::ControlFlow) {
+    fn handle_event(&self, event: Event<'static, T>, control: &mut root::ControlFlow) {
         let is_closed = self.is_closed();
 
         match *self.0.runner.borrow_mut() {
@@ -193,10 +240,7 @@ impl<T: 'static> Shared<T> {
             root::ControlFlow::Poll => {
                 let cloned = self.clone();
                 State::Poll {
-                    timeout: backend::Timeout::new(
-                        move || cloned.send_event(Event::NewEvents(StartCause::Poll)),
-                        Duration::from_millis(0),
-                    ),
+                    timeout: backend::Timeout::new(move || cloned.poll(), Duration::from_millis(0)),
                 }
             }
             root::ControlFlow::Wait => State::Wait {
@@ -217,7 +261,7 @@ impl<T: 'static> Shared<T> {
                     start,
                     end,
                     timeout: backend::Timeout::new(
-                        move || cloned.send_event(Event::NewEvents(StartCause::Poll)),
+                        move || cloned.resume_time_reached(start, end),
                         delay,
                     ),
                 }

src/platform_impl/web/event_loop/window_target.rs

@@ -1,8 +1,8 @@
 use super::{backend, device, proxy::Proxy, runner, window};
-use crate::dpi::LogicalSize;
+use crate::dpi::{PhysicalSize, Size};
 use crate::event::{DeviceId, ElementState, Event, KeyboardInput, TouchPhase, WindowEvent};
 use crate::event_loop::ControlFlow;
-use crate::window::WindowId;
+use crate::window::{Theme, WindowId};
 use std::clone::Clone;
 
 pub struct WindowTarget<T: 'static> {
@@ -28,7 +28,7 @@ impl<T> WindowTarget<T> {
         Proxy::new(self.runner.clone())
     }
 
-    pub fn run(&self, event_handler: Box<dyn FnMut(Event<T>, &mut ControlFlow)>) {
+    pub fn run(&self, event_handler: Box<dyn FnMut(Event<'static, T>, &mut ControlFlow)>) {
         self.runner.set_listener(event_handler);
     }
 
@@ -57,6 +57,7 @@ impl<T> WindowTarget<T> {
 
         let runner = self.runner.clone();
         canvas.on_keyboard_press(move |scancode, virtual_keycode, modifiers| {
+            #[allow(deprecated)]
             runner.send_event(Event::WindowEvent {
                 window_id: WindowId(id),
                 event: WindowEvent::KeyboardInput {
@@ -74,6 +75,7 @@ impl<T> WindowTarget<T> {
 
         let runner = self.runner.clone();
         canvas.on_keyboard_release(move |scancode, virtual_keycode, modifiers| {
+            #[allow(deprecated)]
             runner.send_event(Event::WindowEvent {
                 window_id: WindowId(id),
                 event: WindowEvent::KeyboardInput {
@@ -170,30 +172,45 @@ impl<T> WindowTarget<T> {
 
         let runner = self.runner.clone();
         let raw = canvas.raw().clone();
-        let mut intended_size = LogicalSize {
-            width: raw.width() as f64,
-            height: raw.height() as f64,
+
+        // The size to restore to after exiting fullscreen.
+        let mut intended_size = PhysicalSize {
+            width: raw.width() as u32,
+            height: raw.height() as u32,
         };
         canvas.on_fullscreen_change(move || {
             // If the canvas is marked as fullscreen, it is moving *into* fullscreen
             // If it is not, it is moving *out of* fullscreen
             let new_size = if backend::is_fullscreen(&raw) {
-                intended_size = LogicalSize {
-                    width: raw.width() as f64,
-                    height: raw.height() as f64,
+                intended_size = PhysicalSize {
+                    width: raw.width() as u32,
+                    height: raw.height() as u32,
                 };
 
-                backend::window_size()
+                backend::window_size().to_physical(backend::scale_factor())
             } else {
                 intended_size
             };
-            raw.set_width(new_size.width as u32);
-            raw.set_height(new_size.height as u32);
+
+            backend::set_canvas_size(&raw, Size::Physical(new_size));
             runner.send_event(Event::WindowEvent {
                 window_id: WindowId(id),
                 event: WindowEvent::Resized(new_size),
             });
             runner.request_redraw(WindowId(id));
         });
+
+        let runner = self.runner.clone();
+        canvas.on_dark_mode(move |is_dark_mode| {
+            let theme = if is_dark_mode {
+                Theme::Dark
+            } else {
+                Theme::Light
+            };
+            runner.send_event(Event::WindowEvent {
+                window_id: WindowId(id),
+                event: WindowEvent::ThemeChanged(theme),
+            });
+        });
     }
 }

src/platform_impl/web/mod.rs

@@ -1,6 +1,21 @@
-// TODO: close events (port from old stdweb branch)
-// TODO: pointer locking (stdweb PR required)
-// TODO: fullscreen API (stdweb PR required)
+// Brief introduction to the internals of the web backend:
+// Currently, the web backend supports both wasm-bindgen and stdweb as methods of binding to the
+// environment. Because they are both supporting the same underlying APIs, the actual web bindings
+// are cordoned off into backend abstractions, which present the thinnest unifying layer possible.
+//
+// When adding support for new events or interactions with the browser, first consult trusted
+// documentation (such as MDN) to ensure it is well-standardised and supported across many browsers.
+// Once you have decided on the relevant web APIs, add support to both backends.
+//
+// The backend is used by the rest of the module to implement Winit's business logic, which forms
+// the rest of the code. 'device', 'error', 'monitor', and 'window' define web-specific structures
+// for winit's cross-platform structures. They are all relatively simple translations.
+//
+// The event_loop module handles listening for and processing events. 'Proxy' implements
+// EventLoopProxy and 'WindowTarget' implements EventLoopWindowTarget. WindowTarget also handles
+// registering the event handlers. The 'Execution' struct in the 'runner' module handles taking
+// incoming events (from the registered handlers) and ensuring they are passed to the user in a
+// compliant way.
 
 mod device;
 mod error;
@@ -29,3 +44,5 @@ pub use self::window::{
     Id as WindowId, PlatformSpecificBuilderAttributes as PlatformSpecificWindowBuilderAttributes,
     Window,
 };
+
+pub(crate) use crate::icon::NoIcon as PlatformIcon;

src/platform_impl/web/monitor.rs

@@ -5,22 +5,22 @@ use crate::monitor::{MonitorHandle, VideoMode};
 pub struct Handle;
 
 impl Handle {
-    pub fn hidpi_factor(&self) -> f64 {
+    pub fn scale_factor(&self) -> f64 {
         1.0
     }
 
-    pub fn position(&self) -> PhysicalPosition {
-        PhysicalPosition { x: 0.0, y: 0.0 }
+    pub fn position(&self) -> PhysicalPosition<i32> {
+        PhysicalPosition { x: 0, y: 0 }
     }
 
     pub fn name(&self) -> Option<String> {
         None
     }
 
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         PhysicalSize {
-            width: 0.0,
-            height: 0.0,
+            width: 0,
+            height: 0,
         }
     }
 
@@ -33,7 +33,7 @@ impl Handle {
 pub struct Mode;
 
 impl Mode {
-    pub fn size(&self) -> PhysicalSize {
+    pub fn size(&self) -> PhysicalSize<u32> {
         unimplemented!();
     }
 

src/platform_impl/web/stdweb/canvas.rs

@@ -1,11 +1,12 @@
 use super::event;
-use crate::dpi::{LogicalPosition, LogicalSize};
+use crate::dpi::{LogicalPosition, PhysicalPosition, PhysicalSize};
 use crate::error::OsError as RootOE;
 use crate::event::{ModifiersState, MouseButton, MouseScrollDelta, ScanCode, VirtualKeyCode};
-use crate::platform_impl::OsError;
+use crate::platform_impl::{OsError, PlatformSpecificWindowBuilderAttributes};
 
 use std::cell::RefCell;
 use std::rc::Rc;
+use stdweb::js;
 use stdweb::traits::IPointerEvent;
 use stdweb::unstable::TryInto;
 use stdweb::web::event::{
@@ -19,6 +20,7 @@ use stdweb::web::{
 };
 
 pub struct Canvas {
+    /// Note: resizing the CanvasElement should go through `backend::set_canvas_size` to ensure the DPI factor is maintained.
     raw: CanvasElement,
     on_focus: Option<EventListenerHandle>,
     on_blur: Option<EventListenerHandle>,
@@ -42,12 +44,15 @@ impl Drop for Canvas {
 }
 
 impl Canvas {
-    pub fn create() -> Result<Self, RootOE> {
-        let canvas: CanvasElement = document()
-            .create_element("canvas")
-            .map_err(|_| os_error!(OsError("Failed to create canvas element".to_owned())))?
-            .try_into()
-            .map_err(|_| os_error!(OsError("Failed to create canvas element".to_owned())))?;
+    pub fn create(attr: PlatformSpecificWindowBuilderAttributes) -> Result<Self, RootOE> {
+        let canvas = match attr.canvas {
+            Some(canvas) => canvas,
+            None => document()
+                .create_element("canvas")
+                .map_err(|_| os_error!(OsError("Failed to create canvas element".to_owned())))?
+                .try_into()
+                .map_err(|_| os_error!(OsError("Failed to create canvas element".to_owned())))?,
+        };
 
         // A tabindex is needed in order to capture local keyboard events.
         // A "0" value means that the element should be focusable in
@@ -82,23 +87,20 @@ impl Canvas {
             .expect(&format!("Set attribute: {}", attribute));
     }
 
-    pub fn position(&self) -> (f64, f64) {
+    pub fn position(&self) -> LogicalPosition<f64> {
         let bounds = self.raw.get_bounding_client_rect();
 
-        (bounds.get_x(), bounds.get_y())
+        LogicalPosition {
+            x: bounds.get_x(),
+            y: bounds.get_y(),
+        }
     }
 
-    pub fn width(&self) -> f64 {
-        self.raw.width() as f64
-    }
-
-    pub fn height(&self) -> f64 {
-        self.raw.height() as f64
-    }
-
-    pub fn set_size(&self, size: LogicalSize) {
-        self.raw.set_width(size.width as u32);
-        self.raw.set_height(size.height as u32);
+    pub fn size(&self) -> PhysicalSize<u32> {
+        PhysicalSize {
+            width: self.raw.width() as u32,
+            height: self.raw.height() as u32,
+        }
     }
 
     pub fn raw(&self) -> &CanvasElement {
@@ -209,12 +211,13 @@ impl Canvas {
 
     pub fn on_cursor_move<F>(&mut self, mut handler: F)
     where
-        F: 'static + FnMut(i32, LogicalPosition, ModifiersState),
+        F: 'static + FnMut(i32, PhysicalPosition<f64>, ModifiersState),
     {
+        // todo
         self.on_cursor_move = Some(self.add_event(move |event: PointerMoveEvent| {
             handler(
                 event.pointer_id(),
-                event::mouse_position(&event),
+                event::mouse_position(&event).to_physical(super::scale_factor()),
                 event::mouse_modifiers(&event),
             );
         }));
@@ -238,6 +241,22 @@ impl Canvas {
         self.on_fullscreen_change = Some(self.add_event(move |_: FullscreenChangeEvent| handler()));
     }
 
+    pub fn on_dark_mode<F>(&mut self, handler: F)
+    where
+        F: 'static + FnMut(bool),
+    {
+        // TODO: upstream to stdweb
+        js! {
+            var handler = @{handler};
+
+            if (window.matchMedia) {
+                window.matchMedia("(prefers-color-scheme: dark)").addListener(function(e) {
+                    handler(event.matches)
+                });
+            }
+        }
+    }
+
     fn add_event<E, F>(&self, mut handler: F) -> EventListenerHandle
     where
         E: ConcreteEvent,

src/platform_impl/web/stdweb/event.rs

@@ -23,7 +23,7 @@ pub fn mouse_modifiers(event: &impl IMouseEvent) -> ModifiersState {
     m
 }
 
-pub fn mouse_position(event: &impl IMouseEvent) -> LogicalPosition {
+pub fn mouse_position(event: &impl IMouseEvent) -> LogicalPosition<f64> {
     LogicalPosition {
         x: event.offset_x() as f64,
         y: event.offset_y() as f64,

src/platform_impl/web/stdweb/mod.rs

@@ -5,11 +5,12 @@ mod timeout;
 pub use self::canvas::Canvas;
 pub use self::timeout::Timeout;
 
-use crate::dpi::LogicalSize;
+use crate::dpi::{LogicalSize, Size};
 use crate::platform::web::WindowExtStdweb;
 use crate::window::Window;
 
 use stdweb::js;
+use stdweb::unstable::TryInto;
 use stdweb::web::event::BeforeUnloadEvent;
 use stdweb::web::window;
 use stdweb::web::IEventTarget;
@@ -31,9 +32,18 @@ impl WindowExtStdweb for Window {
     fn canvas(&self) -> CanvasElement {
         self.window.canvas().raw().clone()
     }
+
+    fn is_dark_mode(&self) -> bool {
+        // TODO: upstream to stdweb
+        let is_dark_mode = js! {
+            return (window.matchMedia && window.matchMedia("(prefers-color-scheme: dark)").matches)
+        };
+
+        is_dark_mode.try_into().expect("should return a bool")
+    }
 }
 
-pub fn window_size() -> LogicalSize {
+pub fn window_size() -> LogicalSize<f64> {
     let window = window();
     let width = window.inner_width() as f64;
     let height = window.inner_height() as f64;
@@ -41,6 +51,28 @@ pub fn window_size() -> LogicalSize {
     LogicalSize { width, height }
 }
 
+pub fn scale_factor() -> f64 {
+    let window = window();
+    window.device_pixel_ratio()
+}
+
+pub fn set_canvas_size(raw: &CanvasElement, size: Size) {
+    use stdweb::*;
+
+    let scale_factor = scale_factor();
+
+    let physical_size = size.to_physical::<u32>(scale_factor);
+    let logical_size = size.to_logical::<f64>(scale_factor);
+
+    raw.set_width(physical_size.width);
+    raw.set_height(physical_size.height);
+
+    js! {
+        @{raw.as_ref()}.style.width = @{logical_size.width} + "px";
+        @{raw.as_ref()}.style.height = @{logical_size.height} + "px";
+    }
+}
+
 pub fn is_fullscreen(canvas: &CanvasElement) -> bool {
     match document().fullscreen_element() {
         Some(elem) => {
@@ -50,3 +82,5 @@ pub fn is_fullscreen(canvas: &CanvasElement) -> bool {
         None => false,
     }
 }
+
+pub type RawCanvasType = CanvasElement;

src/platform_impl/web/web_sys/canvas.rs

@@ -1,16 +1,20 @@
 use super::event;
-use crate::dpi::{LogicalPosition, LogicalSize};
+use crate::dpi::{LogicalPosition, PhysicalPosition, PhysicalSize};
 use crate::error::OsError as RootOE;
 use crate::event::{ModifiersState, MouseButton, MouseScrollDelta, ScanCode, VirtualKeyCode};
-use crate::platform_impl::OsError;
+use crate::platform_impl::{OsError, PlatformSpecificWindowBuilderAttributes};
 
 use std::cell::RefCell;
 use std::rc::Rc;
 
 use wasm_bindgen::{closure::Closure, JsCast};
-use web_sys::{Event, FocusEvent, HtmlCanvasElement, KeyboardEvent, PointerEvent, WheelEvent};
+use web_sys::{
+    Event, FocusEvent, HtmlCanvasElement, KeyboardEvent, MediaQueryListEvent, PointerEvent,
+    WheelEvent,
+};
 
 pub struct Canvas {
+    /// Note: resizing the HTMLCanvasElement should go through `backend::set_canvas_size` to ensure the DPI factor is maintained.
     raw: HtmlCanvasElement,
     on_focus: Option<Closure<dyn FnMut(FocusEvent)>>,
     on_blur: Option<Closure<dyn FnMut(FocusEvent)>>,
@@ -25,6 +29,7 @@ pub struct Canvas {
     on_mouse_wheel: Option<Closure<dyn FnMut(WheelEvent)>>,
     on_fullscreen_change: Option<Closure<dyn FnMut(Event)>>,
     wants_fullscreen: Rc<RefCell<bool>>,
+    on_dark_mode: Option<Closure<dyn FnMut(MediaQueryListEvent)>>,
 }
 
 impl Drop for Canvas {
@@ -34,18 +39,23 @@ impl Drop for Canvas {
 }
 
 impl Canvas {
-    pub fn create() -> Result<Self, RootOE> {
-        let window =
-            web_sys::window().ok_or(os_error!(OsError("Failed to obtain window".to_owned())))?;
+    pub fn create(attr: PlatformSpecificWindowBuilderAttributes) -> Result<Self, RootOE> {
+        let canvas = match attr.canvas {
+            Some(canvas) => canvas,
+            None => {
+                let window = web_sys::window()
+                    .ok_or(os_error!(OsError("Failed to obtain window".to_owned())))?;
 
-        let document = window
-            .document()
-            .ok_or(os_error!(OsError("Failed to obtain document".to_owned())))?;
+                let document = window
+                    .document()
+                    .ok_or(os_error!(OsError("Failed to obtain document".to_owned())))?;
 
-        let canvas: HtmlCanvasElement = document
-            .create_element("canvas")
-            .map_err(|_| os_error!(OsError("Failed to create canvas element".to_owned())))?
-            .unchecked_into();
+                document
+                    .create_element("canvas")
+                    .map_err(|_| os_error!(OsError("Failed to create canvas element".to_owned())))?
+                    .unchecked_into()
+            }
+        };
 
         // A tabindex is needed in order to capture local keyboard events.
         // A "0" value means that the element should be focusable in
@@ -71,6 +81,7 @@ impl Canvas {
             on_mouse_wheel: None,
             on_fullscreen_change: None,
             wants_fullscreen: Rc::new(RefCell::new(false)),
+            on_dark_mode: None,
         })
     }
 
@@ -80,23 +91,20 @@ impl Canvas {
             .expect(&format!("Set attribute: {}", attribute));
     }
 
-    pub fn position(&self) -> (f64, f64) {
+    pub fn position(&self) -> LogicalPosition<f64> {
         let bounds = self.raw.get_bounding_client_rect();
 
-        (bounds.x(), bounds.y())
+        LogicalPosition {
+            x: bounds.x(),
+            y: bounds.y(),
+        }
     }
 
-    pub fn width(&self) -> f64 {
-        self.raw.width() as f64
-    }
-
-    pub fn height(&self) -> f64 {
-        self.raw.height() as f64
-    }
-
-    pub fn set_size(&self, size: LogicalSize) {
-        self.raw.set_width(size.width as u32);
-        self.raw.set_height(size.height as u32);
+    pub fn size(&self) -> PhysicalSize<u32> {
+        PhysicalSize {
+            width: self.raw.width(),
+            height: self.raw.height(),
+        }
     }
 
     pub fn raw(&self) -> &HtmlCanvasElement {
@@ -218,12 +226,12 @@ impl Canvas {
 
     pub fn on_cursor_move<F>(&mut self, mut handler: F)
     where
-        F: 'static + FnMut(i32, LogicalPosition, ModifiersState),
+        F: 'static + FnMut(i32, PhysicalPosition<f64>, ModifiersState),
     {
         self.on_cursor_move = Some(self.add_event("pointermove", move |event: PointerEvent| {
             handler(
                 event.pointer_id(),
-                event::mouse_position(&event),
+                event::mouse_position(&event).to_physical(super::scale_factor()),
                 event::mouse_modifiers(&event),
             );
         }));
@@ -248,6 +256,28 @@ impl Canvas {
             Some(self.add_event("fullscreenchange", move |_: Event| handler()));
     }
 
+    pub fn on_dark_mode<F>(&mut self, mut handler: F)
+    where
+        F: 'static + FnMut(bool),
+    {
+        let window = web_sys::window().expect("Failed to obtain window");
+
+        self.on_dark_mode = window
+            .match_media("(prefers-color-scheme: dark)")
+            .ok()
+            .flatten()
+            .and_then(|media| {
+                let closure = Closure::wrap(Box::new(move |event: MediaQueryListEvent| {
+                    handler(event.matches())
+                }) as Box<dyn FnMut(_)>);
+
+                media
+                    .add_listener_with_opt_callback(Some(&closure.as_ref().unchecked_ref()))
+                    .map(|_| closure)
+                    .ok()
+            });
+    }
+
     fn add_event<E, F>(&self, event_name: &str, mut handler: F) -> Closure<dyn FnMut(E)>
     where
         E: 'static + AsRef<web_sys::Event> + wasm_bindgen::convert::FromWasmAbi,

src/platform_impl/web/web_sys/event.rs

@@ -22,7 +22,7 @@ pub fn mouse_modifiers(event: &MouseEvent) -> ModifiersState {
     m
 }
 
-pub fn mouse_position(event: &MouseEvent) -> LogicalPosition {
+pub fn mouse_position(event: &MouseEvent) -> LogicalPosition<f64> {
     LogicalPosition {
         x: event.offset_x() as f64,
         y: event.offset_y() as f64,

src/platform_impl/web/web_sys/mod.rs

@@ -5,7 +5,7 @@ mod timeout;
 pub use self::canvas::Canvas;
 pub use self::timeout::Timeout;
 
-use crate::dpi::LogicalSize;
+use crate::dpi::{LogicalSize, Size};
 use crate::platform::web::WindowExtWebSys;
 use crate::window::Window;
 use wasm_bindgen::{closure::Closure, JsCast};
@@ -38,9 +38,20 @@ impl WindowExtWebSys for Window {
     fn canvas(&self) -> HtmlCanvasElement {
         self.window.canvas().raw().clone()
     }
+
+    fn is_dark_mode(&self) -> bool {
+        let window = web_sys::window().expect("Failed to obtain window");
+
+        window
+            .match_media("(prefers-color-scheme: dark)")
+            .ok()
+            .flatten()
+            .map(|media| media.matches())
+            .unwrap_or(false)
+    }
 }
 
-pub fn window_size() -> LogicalSize {
+pub fn window_size() -> LogicalSize<f64> {
     let window = web_sys::window().expect("Failed to obtain window");
     let width = window
         .inner_width()
@@ -56,6 +67,29 @@ pub fn window_size() -> LogicalSize {
     LogicalSize { width, height }
 }
 
+pub fn scale_factor() -> f64 {
+    let window = web_sys::window().expect("Failed to obtain window");
+    window.device_pixel_ratio()
+}
+
+pub fn set_canvas_size(raw: &HtmlCanvasElement, size: Size) {
+    let scale_factor = scale_factor();
+
+    let physical_size = size.to_physical::<u32>(scale_factor);
+    let logical_size = size.to_logical::<f64>(scale_factor);
+
+    raw.set_width(physical_size.width);
+    raw.set_height(physical_size.height);
+
+    let style = raw.style();
+    style
+        .set_property("width", &format!("{}px", logical_size.width))
+        .expect("Failed to set canvas width");
+    style
+        .set_property("height", &format!("{}px", logical_size.height))
+        .expect("Failed to set canvas height");
+}
+
 pub fn is_fullscreen(canvas: &HtmlCanvasElement) -> bool {
     let window = window().expect("Failed to obtain window");
     let document = window.document().expect("Failed to obtain document");
@@ -68,3 +102,5 @@ pub fn is_fullscreen(canvas: &HtmlCanvasElement) -> bool {
         None => false,
     }
 }
+
+pub type RawCanvasType = HtmlCanvasElement;

src/platform_impl/web/window.rs

@@ -1,4 +1,4 @@
-use crate::dpi::{LogicalPosition, LogicalSize};
+use crate::dpi::{LogicalSize, PhysicalPosition, PhysicalSize, Position, Size};
 use crate::error::{ExternalError, NotSupportedError, OsError as RootOE};
 use crate::icon::Icon;
 use crate::monitor::MonitorHandle as RootMH;
@@ -15,7 +15,6 @@ use std::collections::VecDeque;
 pub struct Window {
     canvas: backend::Canvas,
     previous_pointer: RefCell<&'static str>,
-    position: RefCell<LogicalPosition>,
     id: Id,
     register_redraw_request: Box<dyn Fn()>,
 }
@@ -24,13 +23,13 @@ impl Window {
     pub fn new<T>(
         target: &EventLoopWindowTarget<T>,
         attr: WindowAttributes,
-        _: PlatformSpecificBuilderAttributes,
+        platform_attr: PlatformSpecificBuilderAttributes,
     ) -> Result<Self, RootOE> {
         let runner = target.runner.clone();
 
         let id = target.generate_id();
 
-        let mut canvas = backend::Canvas::create()?;
+        let mut canvas = backend::Canvas::create(platform_attr)?;
 
         let register_redraw_request = Box::new(move || runner.request_redraw(RootWI(id)));
 
@@ -39,15 +38,14 @@ impl Window {
         let window = Window {
             canvas,
             previous_pointer: RefCell::new("auto"),
-            position: RefCell::new(LogicalPosition { x: 0.0, y: 0.0 }),
             id,
             register_redraw_request,
         };
 
-        window.set_inner_size(attr.inner_size.unwrap_or(LogicalSize {
+        window.set_inner_size(attr.inner_size.unwrap_or(Size::Logical(LogicalSize {
             width: 1024.0,
             height: 768.0,
-        }));
+        })));
         window.set_title(&attr.title);
         window.set_maximized(attr.maximized);
         window.set_visible(attr.visible);
@@ -72,18 +70,17 @@ impl Window {
         (self.register_redraw_request)();
     }
 
-    pub fn outer_position(&self) -> Result<LogicalPosition, NotSupportedError> {
-        let (x, y) = self.canvas.position();
-
-        Ok(LogicalPosition { x, y })
+    pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
+        Ok(self.canvas.position().to_physical(self.scale_factor()))
     }
 
-    pub fn inner_position(&self) -> Result<LogicalPosition, NotSupportedError> {
-        Ok(*self.position.borrow())
+    pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
+        // Note: the canvas element has no window decorations, so this is equal to `outer_position`.
+        self.outer_position()
     }
 
-    pub fn set_outer_position(&self, position: LogicalPosition) {
-        *self.position.borrow_mut() = position;
+    pub fn set_outer_position(&self, position: Position) {
+        let position = position.to_logical::<f64>(self.scale_factor());
 
         self.canvas.set_attribute("position", "fixed");
         self.canvas.set_attribute("left", &position.x.to_string());
@@ -91,33 +88,28 @@ impl Window {
     }
 
     #[inline]
-    pub fn inner_size(&self) -> LogicalSize {
-        LogicalSize {
-            width: self.canvas.width() as f64,
-            height: self.canvas.height() as f64,
-        }
+    pub fn inner_size(&self) -> PhysicalSize<u32> {
+        self.canvas.size()
     }
 
     #[inline]
-    pub fn outer_size(&self) -> LogicalSize {
-        LogicalSize {
-            width: self.canvas.width() as f64,
-            height: self.canvas.height() as f64,
-        }
+    pub fn outer_size(&self) -> PhysicalSize<u32> {
+        // Note: the canvas element has no window decorations, so this is equal to `inner_size`.
+        self.inner_size()
     }
 
     #[inline]
-    pub fn set_inner_size(&self, size: LogicalSize) {
-        self.canvas.set_size(size);
+    pub fn set_inner_size(&self, size: Size) {
+        backend::set_canvas_size(self.canvas.raw(), size);
     }
 
     #[inline]
-    pub fn set_min_inner_size(&self, _dimensions: Option<LogicalSize>) {
+    pub fn set_min_inner_size(&self, _dimensions: Option<Size>) {
         // Intentionally a no-op: users can't resize canvas elements
     }
 
     #[inline]
-    pub fn set_max_inner_size(&self, _dimensions: Option<LogicalSize>) {
+    pub fn set_max_inner_size(&self, _dimensions: Option<Size>) {
         // Intentionally a no-op: users can't resize canvas elements
     }
 
@@ -127,8 +119,8 @@ impl Window {
     }
 
     #[inline]
-    pub fn hidpi_factor(&self) -> f64 {
-        1.0
+    pub fn scale_factor(&self) -> f64 {
+        super::backend::scale_factor()
     }
 
     #[inline]
@@ -178,7 +170,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_cursor_position(&self, _position: LogicalPosition) -> Result<(), ExternalError> {
+    pub fn set_cursor_position(&self, _position: Position) -> Result<(), ExternalError> {
         // Intentionally a no-op, as the web does not support setting cursor positions
         Ok(())
     }
@@ -243,7 +235,7 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_position(&self, _position: LogicalPosition) {
+    pub fn set_ime_position(&self, _position: Position) {
         // Currently a no-op as it does not seem there is good support for this on web
     }
 
@@ -289,5 +281,7 @@ impl Id {
     }
 }
 
-#[derive(Debug, Default, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
-pub struct PlatformSpecificBuilderAttributes;
+#[derive(Default, Clone)]
+pub struct PlatformSpecificBuilderAttributes {
+    pub(crate) canvas: Option<backend::RawCanvasType>,
+}

src/platform_impl/windows/dark_mode.rs

@@ -6,9 +6,10 @@ use std::os::windows::ffi::OsStrExt;
 use winapi::{
     shared::{
         basetsd::SIZE_T,
-        minwindef::{BOOL, DWORD, UINT, ULONG, WORD},
+        minwindef::{BOOL, DWORD, FALSE, UINT, ULONG, WORD},
         ntdef::{LPSTR, NTSTATUS, NT_SUCCESS, PVOID, WCHAR},
         windef::HWND,
+        winerror::S_OK,
     },
     um::{libloaderapi, uxtheme, winuser},
 };
@@ -44,9 +45,8 @@ lazy_static! {
                 };
 
                 let status = (rtl_get_version)(&mut vi as _);
-                assert!(NT_SUCCESS(status));
 
-                if vi.dwMajorVersion == 10 && vi.dwMinorVersion == 0 {
+                if NT_SUCCESS(status) && vi.dwMajorVersion == 10 && vi.dwMinorVersion == 0 {
                     Some(vi.dwBuildNumber)
                 } else {
                     None
@@ -82,22 +82,15 @@ pub fn try_dark_mode(hwnd: HWND) -> bool {
             LIGHT_THEME_NAME.as_ptr()
         };
 
-        unsafe {
-            assert_eq!(
-                0,
-                uxtheme::SetWindowTheme(hwnd, theme_name as _, std::ptr::null())
-            );
+        let status = unsafe { uxtheme::SetWindowTheme(hwnd, theme_name as _, std::ptr::null()) };
 
-            set_dark_mode_for_window(hwnd, is_dark_mode)
-        }
-
-        is_dark_mode
+        status == S_OK && set_dark_mode_for_window(hwnd, is_dark_mode)
     } else {
         false
     }
 }
 
-fn set_dark_mode_for_window(hwnd: HWND, is_dark_mode: bool) {
+fn set_dark_mode_for_window(hwnd: HWND, is_dark_mode: bool) -> bool {
     // Uses Windows undocumented API SetWindowCompositionAttribute,
     // as seen in win32-darkmode example linked at top of file.
 
@@ -132,11 +125,12 @@ fn set_dark_mode_for_window(hwnd: HWND, is_dark_mode: bool) {
                 cbData: std::mem::size_of_val(&is_dark_mode_bigbool) as _,
             };
 
-            assert_eq!(
-                1,
-                set_window_composition_attribute(hwnd, &mut data as *mut _)
-            );
+            let status = set_window_composition_attribute(hwnd, &mut data as *mut _);
+
+            status != FALSE
         }
+    } else {
+        false
     }
 }
 
@@ -205,7 +199,7 @@ fn is_high_contrast() -> bool {
         )
     };
 
-    (ok > 0) && ((HCF_HIGHCONTRASTON & hc.dwFlags) == 1)
+    ok != FALSE && (HCF_HIGHCONTRASTON & hc.dwFlags) == 1
 }
 
 fn widestring(src: &'static str) -> Vec<u16> {