Release 0.22.2 (#1570)

* update macos libs

* modify dependency

* changelog

* update core-video-sys version

.github/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
   Check_Formatting:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - uses: hecrj/setup-rust-action@v1
       with:
         rust-version: stable
@@ -37,24 +37,25 @@ jobs:
           - { 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: aarch64-linux-android,    os: ubuntu-latest,  cmd: 'apk --' }
           - { 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 }
+          - { target: wasm32-unknown-unknown,   os: windows-latest, features: stdweb,  cmd: web }
+          - { target: wasm32-unknown-unknown,   os: windows-latest, features: web-sys, cmd: web }
 
     env:
       RUST_BACKTRACE: 1
       CARGO_INCREMENTAL: 0
       RUSTFLAGS: "-C debuginfo=0"
       FEATURES: ${{ format(',{0}', matrix.platform.features ) }}
-      WEB: ${{ matrix.platform.web }}
+      CMD: ${{ matrix.platform.cmd }}
 
     runs-on: ${{ matrix.platform.os }}
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     # Used to cache cargo-web
     - name: Cache cargo folder
       uses: actions/cache@v1
@@ -70,6 +71,9 @@ jobs:
     - 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-apk
+      if: contains(matrix.platform.target, 'android')
+      run: cargo install cargo-apk
     - name: Install cargo-web
       continue-on-error: true
       if: contains(matrix.platform.target, 'wasm32')
@@ -78,29 +82,35 @@ jobs:
     - name: Check documentation
       shell: bash
       if: matrix.platform.target != 'wasm32-unknown-unknown'
-      run: cargo doc --no-deps --target ${{ matrix.platform.target }} --features $FEATURES
+      run: cargo $CMD doc --no-deps --target ${{ matrix.platform.target }} --features $FEATURES
 
     - name: Build
       shell: bash
-      run: cargo $WEB build --verbose --target ${{ matrix.platform.target }} --features $FEATURES
+      run: cargo $CMD 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
+      run: cargo $CMD 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
+      if: (
+        !contains(matrix.platform.target, 'android') &&
+        !contains(matrix.platform.target, 'ios') &&
+        !contains(matrix.platform.target, 'wasm32'))
+      run: cargo $CMD 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
+      run: cargo $CMD 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
+      run: cargo $CMD 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
+      if: (
+        !contains(matrix.platform.target, 'android') &&
+        !contains(matrix.platform.target, 'ios') &&
+        !contains(matrix.platform.target, 'wasm32'))
+      run: cargo $CMD test --verbose --target ${{ matrix.platform.target }} --features serde,$FEATURES

.github/workflows/publish.yml

@@ -9,7 +9,7 @@ jobs:
   Publish:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - uses: hecrj/setup-rust-action@v1
       with:
         rust-version: stable

CHANGELOG.md

@@ -1,5 +1,43 @@
 # Unreleased
 
+# 0.22.2 (2020-05-16)
+
+- Added Clone implementation for 'static events.
+- On Windows, fix window intermittently hanging when `ControlFlow` was set to `Poll`.
+- On Windows, fix `WindowBuilder::with_maximized` being ignored.
+- On Android, minimal platform support.
+- On iOS, touch positions are now properly converted to physical pixels.
+- On macOS, updated core-* dependencies and cocoa
+
+# 0.22.1 (2020-04-16)
+
+- On X11, fix `ResumeTimeReached` being fired too early.
+- On Web, replaced zero timeout for `ControlFlow::Poll` with `requestAnimationFrame`
+- On Web, fix a possible panic during event handling
+- On macOS, fix `EventLoopProxy` leaking memory for every instance.
+
+# 0.22.0 (2020-03-09)
+
+- 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`.
+- On macOS, a mouse motion event is now generated before every mouse click.
+
 # 0.21.0 (2020-02-04)
 
 - On Windows, fixed "error: linking with `link.exe` failed: exit code: 1120" error on older versions of windows.
@@ -20,7 +58,6 @@
 # 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.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "winit"
-version = "0.21.0"
+version = "0.22.2"
 authors = ["The winit contributors", "Pierre Krieger <pierre.krieger1708@gmail.com>"]
 description = "Cross-platform window creation library."
 edition = "2018"
@@ -12,7 +12,9 @@ documentation = "https://docs.rs/winit"
 categories = ["gui"]
 
 [package.metadata.docs.rs]
-features = ["serde"]
+features = ["serde", "web-sys"]
+default-target = "x86_64-unknown-linux-gnu"
+targets = ["i686-pc-windows-msvc", "x86_64-pc-windows-msvc", "i686-unknown-linux-gnu", "x86_64-unknown-linux-gnu", "x86_64-apple-darwin", "wasm32-unknown-unknown"]
 
 [features]
 web-sys = ["web_sys", "wasm-bindgen", "instant/wasm-bindgen"]
@@ -28,24 +30,26 @@ raw-window-handle = "0.3"
 bitflags = "1"
 
 [dev-dependencies]
-image = "0.21"
+image = "0.23"
 simple_logger = "1"
 
-[target.'cfg(target_os = "android")'.dependencies.android_glue]
-version = "0.2"
+[target.'cfg(target_os = "android")'.dependencies]
+ndk = "0.1.0"
+ndk-sys = "0.1.0"
+ndk-glue = "0.1.0"
 
 [target.'cfg(target_os = "ios")'.dependencies]
 objc = "0.2.3"
 
 [target.'cfg(target_os = "macos")'.dependencies]
-cocoa = "0.19.1"
-core-foundation = "0.6"
-core-graphics = "0.17.3"
+cocoa = "0.20"
+core-foundation = "0.7"
+core-graphics = "0.19"
 dispatch = "0.2.0"
 objc = "0.2.6"
 
 [target.'cfg(target_os = "macos")'.dependencies.core-video-sys]
-version = "0.1.3"
+version = "0.1.4"
 default_features = false
 features = ["display_link"]
 
@@ -77,8 +81,8 @@ features = [
 wayland-client = { version = "0.23.0", features = [ "dlopen", "egl", "cursor", "eventloop"] }
 mio = "0.6"
 mio-extras = "2.0"
-smithay-client-toolkit = "0.6"
-x11-dl = "2.18.3"
+smithay-client-toolkit = "^0.6.6"
+x11-dl = "2.18.5"
 percent-encoding = "2.0"
 
 [target.'cfg(any(target_os = "linux", target_os = "dragonfly", target_os = "freebsd", target_os = "openbsd", target_os = "netbsd", target_os = "windows"))'.dependencies.parking_lot]
@@ -101,6 +105,8 @@ features = [
     'HtmlCanvasElement',
     'HtmlElement',
     'KeyboardEvent',
+    'MediaQueryList',
+    'MediaQueryListEvent',
     'MouseEvent',
     'Node',
     'PointerEvent',

FEATURES.md

@@ -109,8 +109,8 @@ If your PR makes notable changes to Winit's features, please update this section
   translating keypresses into UTF-8 characters, handling dead keys and IMEs.
 - **Drag & Drop**: Dragging content into winit, detecting when content enters, drops, or if the drop is cancelled.
 - **Raw Device Events**: Capturing input from input devices without any OS filtering.
-- **Gamepad/Joystick events**: Capturing input from gampads and joysticks.
-- **Device movement events:**: Capturing input from the device gyroscope and accelerometer.
+- **Gamepad/Joystick events**: Capturing input from gamepads and joysticks.
+- **Device movement events**: Capturing input from the device gyroscope and accelerometer.
 
 ## Platform
 ### Windows
@@ -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

@@ -2,12 +2,11 @@
 
 [![Crates.io](https://img.shields.io/crates/v/winit.svg)](https://crates.io/crates/winit)
 [![Docs.rs](https://docs.rs/winit/badge.svg)](https://docs.rs/winit)
-[![Build Status](https://travis-ci.org/rust-windowing/winit.svg?branch=master)](https://travis-ci.org/rust-windowing/winit)
-[![Build status](https://ci.appveyor.com/api/projects/status/hr89but4x1n3dphq/branch/master?svg=true)](https://ci.appveyor.com/project/Osspial/winit/branch/master)
+[![CI Status](https://github.com/rust-windowing/winit/workflows/CI/badge.svg)](https://github.com/rust-windowing/winit/actions)
 
 ```toml
 [dependencies]
-winit = "0.21.0"
+winit = "0.22.2"
 ```
 
 ## [Documentation](https://docs.rs/winit)
@@ -77,3 +76,22 @@ Building a binary will yield a `.js` file. In order to use it in an HTML file, y
   the element of the `<canvas>` element (in the example you would retrieve it via `document.getElementById("my_id")`).
   More information [here](https://kripken.github.io/emscripten-site/docs/api_reference/module.html).
 - Make sure that you insert the `.js` file generated by Rust after the `Module` variable is created.
+
+#### Android
+
+This library makes use of the [ndk-rs](https://github.com/rust-windowing/android-ndk-rs) crates, refer to that repo for more documentation.
+
+Running on an Android device needs a dynamic system library, add this to Cargo.toml:
+```toml
+[[example]]
+name = "request_redraw_threaded"
+crate-type = ["cdylib"]
+```
+
+And add this to the example file to add the native activity glue:
+```rust
+#[cfg(target_os = "android")]
+ndk_glue::ndk_glue!(main);
+```
+
+And run the application with `cargo apk run --example request_redraw_threaded`

examples/control_flow.rs

@@ -0,0 +1,113 @@
+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 = match start_cause {
+                    StartCause::WaitCancelled { .. } => mode == Mode::WaitUntil,
+                    _ => 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_grab.rs

@@ -38,6 +38,7 @@ fn main() {
                         _ => (),
                     }
                 }
+                WindowEvent::ModifiersChanged(m) => modifiers = m,
                 _ => (),
             },
             Event::DeviceEvent { event, .. } => match event {
@@ -46,7 +47,6 @@ fn main() {
                     ElementState::Pressed => println!("mouse button {} pressed", button),
                     ElementState::Released => println!("mouse button {} released", button),
                 },
-                DeviceEvent::ModifiersChanged(m) => modifiers = m,
                 _ => (),
             },
             _ => (),

examples/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/window_icon.rs

@@ -45,13 +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")

src/dpi.rs

@@ -151,8 +151,8 @@ impl Pixel for f64 {
 /// 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_scale_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.
@@ -178,16 +178,16 @@ impl<P: Pixel> LogicalPosition<P> {
     #[inline]
     pub fn from_physical<T: Into<PhysicalPosition<X>>, X: Pixel>(
         physical: T,
-        dpi_factor: f64,
+        scale_factor: f64,
     ) -> Self {
-        physical.into().to_logical(dpi_factor)
+        physical.into().to_logical(scale_factor)
     }
 
     #[inline]
-    pub fn to_physical<X: Pixel>(&self, dpi_factor: f64) -> PhysicalPosition<X> {
-        assert!(validate_scale_factor(dpi_factor));
-        let x = self.x.into() * dpi_factor;
-        let y = self.y.into() * dpi_factor;
+    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()
     }
 
@@ -243,16 +243,16 @@ impl<P: Pixel> PhysicalPosition<P> {
     #[inline]
     pub fn from_logical<T: Into<LogicalPosition<X>>, X: Pixel>(
         logical: T,
-        dpi_factor: f64,
+        scale_factor: f64,
     ) -> Self {
-        logical.into().to_physical(dpi_factor)
+        logical.into().to_physical(scale_factor)
     }
 
     #[inline]
-    pub fn to_logical<X: Pixel>(&self, dpi_factor: f64) -> LogicalPosition<X> {
-        assert!(validate_scale_factor(dpi_factor));
-        let x = self.x.into() / dpi_factor;
-        let y = self.y.into() / dpi_factor;
+    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()
     }
 
@@ -306,15 +306,18 @@ impl<P> LogicalSize<P> {
 
 impl<P: Pixel> LogicalSize<P> {
     #[inline]
-    pub fn from_physical<T: Into<PhysicalSize<X>>, X: Pixel>(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<X: Pixel>(&self, dpi_factor: f64) -> PhysicalSize<X> {
-        assert!(validate_scale_factor(dpi_factor));
-        let width = self.width.into() * dpi_factor;
-        let height = self.height.into() * dpi_factor;
+    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()
     }
 
@@ -368,15 +371,15 @@ impl<P> PhysicalSize<P> {
 
 impl<P: Pixel> PhysicalSize<P> {
     #[inline]
-    pub fn from_logical<T: Into<LogicalSize<X>>, X: Pixel>(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<X: Pixel>(&self, dpi_factor: f64) -> LogicalSize<X> {
-        assert!(validate_scale_factor(dpi_factor));
-        let width = self.width.into() / dpi_factor;
-        let height = self.height.into() / dpi_factor;
+    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()
     }
 
@@ -426,17 +429,17 @@ impl Size {
         size.into()
     }
 
-    pub fn to_logical<P: Pixel>(&self, dpi_factor: f64) -> LogicalSize<P> {
+    pub fn to_logical<P: Pixel>(&self, scale_factor: f64) -> LogicalSize<P> {
         match *self {
-            Size::Physical(size) => size.to_logical(dpi_factor),
+            Size::Physical(size) => size.to_logical(scale_factor),
             Size::Logical(size) => size.cast(),
         }
     }
 
-    pub fn to_physical<P: Pixel>(&self, dpi_factor: f64) -> PhysicalSize<P> {
+    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(dpi_factor),
+            Size::Logical(size) => size.to_physical(scale_factor),
         }
     }
 }
@@ -468,17 +471,17 @@ impl Position {
         position.into()
     }
 
-    pub fn to_logical<P: Pixel>(&self, dpi_factor: f64) -> LogicalPosition<P> {
+    pub fn to_logical<P: Pixel>(&self, scale_factor: f64) -> LogicalPosition<P> {
         match *self {
-            Position::Physical(position) => position.to_logical(dpi_factor),
+            Position::Physical(position) => position.to_logical(scale_factor),
             Position::Logical(position) => position.cast(),
         }
     }
 
-    pub fn to_physical<P: Pixel>(&self, dpi_factor: f64) -> PhysicalPosition<P> {
+    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(dpi_factor),
+            Position::Logical(position) => position.to_physical(scale_factor),
         }
     }
 }

src/event.rs

@@ -81,10 +81,11 @@ pub enum Event<'a, T: 'static> {
     ///
     /// 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
+    /// calculations, etc) that happens as the "main body" of your event loop. If your program only draws
+    /// graphics when something changes, it's usually better to do it in response to
     /// [`Event::RedrawRequested`](crate::event::Event::RedrawRequested), which gets emitted
-    /// immediately after this event.
+    /// immediately after this event. Programs that draw graphics continuously, like most games,
+    /// can render here unconditionally for simplicity.
     MainEventsCleared,
 
     /// Emitted after `MainEventsCleared` when a window should be redrawn.
@@ -97,6 +98,9 @@ pub enum Event<'a, T: 'static> {
     ///
     /// During each iteration of the event loop, Winit will aggregate duplicate redraw requests
     /// into a single event, to help avoid duplicating rendering work.
+    ///
+    /// Mainly of interest to applications with mostly-static graphics that avoid redrawing unless
+    /// something changes, like most non-game GUIs.
     RedrawRequested(WindowId),
 
     /// Emitted after all `RedrawRequested` events have been processed and control flow is about to
@@ -114,6 +118,30 @@ pub enum Event<'a, T: 'static> {
     LoopDestroyed,
 }
 
+impl<T: Clone> Clone for Event<'static, T> {
+    fn clone(&self) -> Self {
+        use self::Event::*;
+        match self {
+            WindowEvent { window_id, event } => WindowEvent {
+                window_id: *window_id,
+                event: event.clone(),
+            },
+            UserEvent(event) => UserEvent(event.clone()),
+            DeviceEvent { device_id, event } => DeviceEvent {
+                device_id: *device_id,
+                event: event.clone(),
+            },
+            NewEvents(cause) => NewEvents(cause.clone()),
+            MainEventsCleared => MainEventsCleared,
+            RedrawRequested(wid) => RedrawRequested(*wid),
+            RedrawEventsCleared => RedrawEventsCleared,
+            LoopDestroyed => LoopDestroyed,
+            Suspended => Suspended,
+            Resumed => Resumed,
+        }
+    }
+}
+
 impl<'a, T> Event<'a, T> {
     pub fn map_nonuser_event<U>(self) -> Result<Event<'a, U>, Event<'a, T>> {
         use self::Event::*;
@@ -139,7 +167,7 @@ impl<'a, T> Event<'a, T> {
             WindowEvent { window_id, event } => event
                 .to_static()
                 .map(|event| WindowEvent { window_id, event }),
-            UserEvent(_) => None,
+            UserEvent(event) => Some(UserEvent(event)),
             DeviceEvent { device_id, event } => Some(DeviceEvent { device_id, event }),
             NewEvents(cause) => Some(NewEvents(cause)),
             MainEventsCleared => Some(MainEventsCleared),
@@ -185,7 +213,7 @@ pub enum WindowEvent<'a> {
     Resized(PhysicalSize<u32>),
 
     /// The position of the window has changed. Contains the window's new position.
-    Moved(PhysicalPosition<u32>),
+    Moved(PhysicalPosition<i32>),
 
     /// The window has been requested to close.
     CloseRequested,
@@ -235,6 +263,13 @@ pub enum WindowEvent<'a> {
         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,
@@ -243,7 +278,7 @@ pub enum WindowEvent<'a> {
         /// 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: PhysicalPosition<f64>,
-        #[deprecated = "Deprecated in favor of DeviceEvent::ModifiersChanged"]
+        #[deprecated = "Deprecated in favor of WindowEvent::ModifiersChanged"]
         modifiers: ModifiersState,
     },
 
@@ -258,7 +293,7 @@ pub enum WindowEvent<'a> {
         device_id: DeviceId,
         delta: MouseScrollDelta,
         phase: TouchPhase,
-        #[deprecated = "Deprecated in favor of DeviceEvent::ModifiersChanged"]
+        #[deprecated = "Deprecated in favor of WindowEvent::ModifiersChanged"]
         modifiers: ModifiersState,
     },
 
@@ -267,7 +302,7 @@ pub enum WindowEvent<'a> {
         device_id: DeviceId,
         state: ElementState,
         button: MouseButton,
-        #[deprecated = "Deprecated in favor of DeviceEvent::ModifiersChanged"]
+        #[deprecated = "Deprecated in favor of WindowEvent::ModifiersChanged"]
         modifiers: ModifiersState,
     },
 
@@ -319,6 +354,97 @@ pub enum WindowEvent<'a> {
     ThemeChanged(Theme),
 }
 
+impl Clone for WindowEvent<'static> {
+    fn clone(&self) -> Self {
+        use self::WindowEvent::*;
+        return match self {
+            Resized(size) => Resized(size.clone()),
+            Moved(pos) => Moved(pos.clone()),
+            CloseRequested => CloseRequested,
+            Destroyed => Destroyed,
+            DroppedFile(file) => DroppedFile(file.clone()),
+            HoveredFile(file) => HoveredFile(file.clone()),
+            HoveredFileCancelled => HoveredFileCancelled,
+            ReceivedCharacter(c) => ReceivedCharacter(*c),
+            Focused(f) => Focused(*f),
+            KeyboardInput {
+                device_id,
+                input,
+                is_synthetic,
+            } => KeyboardInput {
+                device_id: *device_id,
+                input: *input,
+                is_synthetic: *is_synthetic,
+            },
+
+            ModifiersChanged(modifiers) => ModifiersChanged(modifiers.clone()),
+            #[allow(deprecated)]
+            CursorMoved {
+                device_id,
+                position,
+                modifiers,
+            } => CursorMoved {
+                device_id: *device_id,
+                position: *position,
+                modifiers: *modifiers,
+            },
+            CursorEntered { device_id } => CursorEntered {
+                device_id: *device_id,
+            },
+            CursorLeft { device_id } => CursorLeft {
+                device_id: *device_id,
+            },
+            #[allow(deprecated)]
+            MouseWheel {
+                device_id,
+                delta,
+                phase,
+                modifiers,
+            } => MouseWheel {
+                device_id: *device_id,
+                delta: *delta,
+                phase: *phase,
+                modifiers: *modifiers,
+            },
+            #[allow(deprecated)]
+            MouseInput {
+                device_id,
+                state,
+                button,
+                modifiers,
+            } => MouseInput {
+                device_id: *device_id,
+                state: *state,
+                button: *button,
+                modifiers: *modifiers,
+            },
+            TouchpadPressure {
+                device_id,
+                pressure,
+                stage,
+            } => TouchpadPressure {
+                device_id: *device_id,
+                pressure: *pressure,
+                stage: *stage,
+            },
+            AxisMotion {
+                device_id,
+                axis,
+                value,
+            } => AxisMotion {
+                device_id: *device_id,
+                axis: *axis,
+                value: *value,
+            },
+            Touch(touch) => Touch(*touch),
+            ThemeChanged(theme) => ThemeChanged(theme.clone()),
+            ScaleFactorChanged { .. } => {
+                unreachable!("Static event can't be about scale factor changing")
+            }
+        };
+    }
+}
+
 impl<'a> WindowEvent<'a> {
     pub fn to_static(self) -> Option<WindowEvent<'static>> {
         use self::WindowEvent::*;
@@ -341,6 +467,7 @@ impl<'a> WindowEvent<'a> {
                 input,
                 is_synthetic,
             }),
+            ModifiersChanged(modifiers) => Some(ModifiersChanged(modifiers)),
             #[allow(deprecated)]
             CursorMoved {
                 device_id,
@@ -464,16 +591,6 @@ 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,
     },
@@ -502,7 +619,7 @@ 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,
 }
 
@@ -807,8 +924,10 @@ pub enum VirtualKeyCode {
     Multiply,
     Mute,
     MyComputer,
-    NavigateForward,  // also called "Prior"
-    NavigateBackward, // also called "Next"
+    // also called "Next"
+    NavigateForward,
+    // also called "Prior"
+    NavigateBackward,
     NextTrack,
     NoConvert,
     NumpadComma,

src/event_loop.rs

@@ -72,7 +72,8 @@ impl<T> fmt::Debug for EventLoopWindowTarget<T> {
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub enum ControlFlow {
     /// When the current loop iteration finishes, immediately begin a new iteration regardless of
-    /// whether or not new events are available to process.
+    /// whether or not new events are available to process. For web, events are sent when
+    /// `requestAnimationFrame` fires.
     Poll,
     /// When the current loop iteration finishes, suspend the thread until another event arrives.
     Wait,

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
@@ -25,6 +26,8 @@ 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 {
@@ -43,6 +46,7 @@ impl fmt::Display for BadIcon {
                 "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,
             ),
+            BadIcon::OsError(e) => write!(f, "OS error when instantiating the icon: {:?}", e),
         }
     }
 }
@@ -54,38 +58,78 @@ impl Error for BadIcon {
 }
 
 #[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

@@ -73,14 +73,18 @@
 //!             // Application update code.
 //!
 //!             // Queue a RedrawRequested event.
+//!             //
+//!             // You only need to call this if you've determined that you need to redraw, in
+//!             // applications which do not always need to. Applications that redraw continuously
+//!             // can just render here instead.
 //!             window.request_redraw();
 //!         },
 //!         Event::RedrawRequested(_) => {
 //!             // Redraw the application.
 //!             //
-//!             // It's preferrable to render in this event rather than in MainEventsCleared, since
-//!             // rendering in here allows the program to gracefully handle redraws requested
-//!             // by the OS.
+//!             // It's preferable for applications that do not render continuously to render in
+//!             // this event rather than in MainEventsCleared, since rendering in here allows
+//!             // the program to gracefully handle redraws requested by the OS.
 //!         },
 //!         _ => ()
 //!     }
@@ -94,8 +98,15 @@
 //! # Drawing on the window
 //!
 //! 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 can be used to render graphics.
+//! retrieve the raw handle of the window (see the [`platform`] module and/or the
+//! [`raw_window_handle`] method), which in turn allows you to create an
+//! OpenGL/Vulkan/DirectX/Metal/etc. context that can be used to render graphics.
+//!
+//! Note that many platforms will display garbage data in the window's client area if the
+//! application doesn't render anything to the window by the time the desktop compositor is ready to
+//! display the window to the user. If you notice this happening, you should create the window with
+//! [`visible` set to `false`](crate::window::WindowBuilder::with_visible) and explicitly make the
+//! window visible only once you're ready to render into it.
 //!
 //! [`EventLoop`]: event_loop::EventLoop
 //! [`EventLoopExtDesktop::run_return`]: ./platform/desktop/trait.EventLoopExtDesktop.html#tymethod.run_return
@@ -116,6 +127,7 @@
 //! [`UserEvent`]: event::Event::UserEvent
 //! [`LoopDestroyed`]: event::Event::LoopDestroyed
 //! [`platform`]: platform
+//! [`raw_window_handle`]: ./window/struct.Window.html#method.raw_window_handle
 
 #![deny(rust_2018_idioms)]
 #![deny(intra_doc_link_resolution_failure)]

src/platform/android.rs

@@ -1,32 +1,39 @@
 #![cfg(any(target_os = "android"))]
 
-use crate::{EventLoop, Window, WindowBuilder};
-use std::os::raw::c_void;
+use crate::{
+    event_loop::{EventLoop, EventLoopWindowTarget},
+    window::{Window, WindowBuilder},
+};
+use ndk::configuration::Configuration;
+use ndk_glue::Rect;
 
 /// Additional methods on `EventLoop` that are specific to Android.
-pub trait EventLoopExtAndroid {
-    /// Makes it possible for glutin to register a callback when a suspend event happens on Android
-    fn set_suspend_callback(&self, cb: Option<Box<dyn Fn(bool) -> ()>>);
-}
+pub trait EventLoopExtAndroid {}
 
-impl EventLoopExtAndroid for EventLoop {
-    fn set_suspend_callback(&self, cb: Option<Box<dyn Fn(bool) -> ()>>) {
-        self.event_loop.set_suspend_callback(cb);
-    }
-}
+impl<T> EventLoopExtAndroid for EventLoop<T> {}
+
+/// Additional methods on `EventLoopWindowTarget` that are specific to Android.
+pub trait EventLoopWindowTargetExtAndroid {}
 
 /// Additional methods on `Window` that are specific to Android.
 pub trait WindowExtAndroid {
-    fn native_window(&self) -> *const c_void;
+    fn content_rect(&self) -> Rect;
+
+    fn config(&self) -> Configuration;
 }
 
 impl WindowExtAndroid for Window {
-    #[inline]
-    fn native_window(&self) -> *const c_void {
-        self.window.native_window()
+    fn content_rect(&self) -> Rect {
+        self.window.content_rect()
+    }
+
+    fn config(&self) -> Configuration {
+        self.window.config()
     }
 }
 
+impl<T> EventLoopWindowTargetExtAndroid for EventLoopWindowTarget<T> {}
+
 /// Additional methods on `WindowBuilder` that are specific to Android.
 pub trait WindowBuilderExtAndroid {}
 

src/platform/unix.rs

@@ -446,7 +446,8 @@ impl<T: Theme> SCTKTheme for WaylandTheme<T> {
     }
 
     fn get_close_button_icon_color(&self, status: SCTKButtonState) -> [u8; 4] {
-        self.0.close_button_color(ButtonState::from_sctk(status))
+        self.0
+            .close_button_icon_color(ButtonState::from_sctk(status))
     }
 
     fn get_maximize_button_color(&self, status: SCTKButtonState) -> [u8; 4] {

src/platform/web.rs

@@ -14,6 +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")]
@@ -22,6 +25,9 @@ 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")]

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/ffi.rs

@@ -1,122 +0,0 @@
-#![allow(dead_code)]
-#![allow(non_snake_case)]
-#![allow(non_camel_case_types)]
-#![allow(non_upper_case_globals)]
-
-use libc;
-use std::os::raw;
-
-#[link(name = "android")]
-#[link(name = "EGL")]
-#[link(name = "GLESv2")]
-extern "C" {}
-
-/**
- ** asset_manager.h
- **/
-pub type AAssetManager = raw::c_void;
-
-/**
- ** native_window.h
- **/
-pub type ANativeWindow = raw::c_void;
-
-extern "C" {
-    pub fn ANativeWindow_getHeight(window: *const ANativeWindow) -> libc::int32_t;
-    pub fn ANativeWindow_getWidth(window: *const ANativeWindow) -> libc::int32_t;
-}
-
-/**
- ** native_activity.h
- **/
-pub type JavaVM = ();
-pub type JNIEnv = ();
-pub type jobject = *const libc::c_void;
-
-pub type AInputQueue = (); // FIXME: wrong
-pub type ARect = (); // FIXME: wrong
-
-#[repr(C)]
-pub struct ANativeActivity {
-    pub callbacks: *mut ANativeActivityCallbacks,
-    pub vm: *mut JavaVM,
-    pub env: *mut JNIEnv,
-    pub clazz: jobject,
-    pub internalDataPath: *const libc::c_char,
-    pub externalDataPath: *const libc::c_char,
-    pub sdkVersion: libc::int32_t,
-    pub instance: *mut libc::c_void,
-    pub assetManager: *mut AAssetManager,
-    pub obbPath: *const libc::c_char,
-}
-
-#[repr(C)]
-pub struct ANativeActivityCallbacks {
-    pub onStart: extern "C" fn(*mut ANativeActivity),
-    pub onResume: extern "C" fn(*mut ANativeActivity),
-    pub onSaveInstanceState: extern "C" fn(*mut ANativeActivity, *mut libc::size_t),
-    pub onPause: extern "C" fn(*mut ANativeActivity),
-    pub onStop: extern "C" fn(*mut ANativeActivity),
-    pub onDestroy: extern "C" fn(*mut ANativeActivity),
-    pub onWindowFocusChanged: extern "C" fn(*mut ANativeActivity, libc::c_int),
-    pub onNativeWindowCreated: extern "C" fn(*mut ANativeActivity, *const ANativeWindow),
-    pub onNativeWindowResized: extern "C" fn(*mut ANativeActivity, *const ANativeWindow),
-    pub onNativeWindowRedrawNeeded: extern "C" fn(*mut ANativeActivity, *const ANativeWindow),
-    pub onNativeWindowDestroyed: extern "C" fn(*mut ANativeActivity, *const ANativeWindow),
-    pub onInputQueueCreated: extern "C" fn(*mut ANativeActivity, *mut AInputQueue),
-    pub onInputQueueDestroyed: extern "C" fn(*mut ANativeActivity, *mut AInputQueue),
-    pub onContentRectChanged: extern "C" fn(*mut ANativeActivity, *const ARect),
-    pub onConfigurationChanged: extern "C" fn(*mut ANativeActivity),
-    pub onLowMemory: extern "C" fn(*mut ANativeActivity),
-}
-
-/**
- ** looper.h
- **/
-pub type ALooper = ();
-
-#[link(name = "android")]
-extern "C" {
-    pub fn ALooper_forThread() -> *const ALooper;
-    pub fn ALooper_acquire(looper: *const ALooper);
-    pub fn ALooper_release(looper: *const ALooper);
-    pub fn ALooper_prepare(opts: libc::c_int) -> *const ALooper;
-    pub fn ALooper_pollOnce(
-        timeoutMillis: libc::c_int,
-        outFd: *mut libc::c_int,
-        outEvents: *mut libc::c_int,
-        outData: *mut *mut libc::c_void,
-    ) -> libc::c_int;
-    pub fn ALooper_pollAll(
-        timeoutMillis: libc::c_int,
-        outFd: *mut libc::c_int,
-        outEvents: *mut libc::c_int,
-        outData: *mut *mut libc::c_void,
-    ) -> libc::c_int;
-    pub fn ALooper_wake(looper: *const ALooper);
-    pub fn ALooper_addFd(
-        looper: *const ALooper,
-        fd: libc::c_int,
-        ident: libc::c_int,
-        events: libc::c_int,
-        callback: ALooper_callbackFunc,
-        data: *mut libc::c_void,
-    ) -> libc::c_int;
-    pub fn ALooper_removeFd(looper: *const ALooper, fd: libc::c_int) -> libc::c_int;
-}
-
-pub const ALOOPER_PREPARE_ALLOW_NON_CALLBACKS: libc::c_int = 1 << 0;
-
-pub const ALOOPER_POLL_WAKE: libc::c_int = -1;
-pub const ALOOPER_POLL_CALLBACK: libc::c_int = -2;
-pub const ALOOPER_POLL_TIMEOUT: libc::c_int = -3;
-pub const ALOOPER_POLL_ERROR: libc::c_int = -4;
-
-pub const ALOOPER_EVENT_INPUT: libc::c_int = 1 << 0;
-pub const ALOOPER_EVENT_OUTPUT: libc::c_int = 1 << 1;
-pub const ALOOPER_EVENT_ERROR: libc::c_int = 1 << 2;
-pub const ALOOPER_EVENT_HANGUP: libc::c_int = 1 << 3;
-pub const ALOOPER_EVENT_INVALID: libc::c_int = 1 << 4;
-
-pub type ALooper_callbackFunc =
-    extern "C" fn(libc::c_int, libc::c_int, *mut libc::c_void) -> libc::c_int;

src/platform_impl/android/mod.rs

@@ -1,448 +1,519 @@
 #![cfg(target_os = "android")]
 
-extern crate android_glue;
-
-mod ffi;
-
-use std::{
-    cell::RefCell,
-    collections::VecDeque,
-    fmt,
-    os::raw::c_void,
-    sync::mpsc::{channel, Receiver},
-};
-
 use crate::{
-    error::{ExternalError, NotSupportedError},
-    events::{Touch, TouchPhase},
-    window::MonitorHandle as RootMonitorHandle,
-    CreationError, CursorIcon, Event, LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize,
-    WindowAttributes, WindowEvent, WindowId as RootWindowId,
+    dpi::{PhysicalPosition, PhysicalSize, Position, Size},
+    error, event,
+    event_loop::{self, ControlFlow},
+    monitor, window,
+};
+use ndk::{
+    configuration::Configuration,
+    event::{InputEvent, MotionAction},
+    looper::{ForeignLooper, Poll, ThreadLooper},
+};
+use ndk_glue::{Event, Rect};
+use std::{
+    collections::VecDeque,
+    sync::{Arc, Mutex, RwLock},
+    time::{Duration, Instant},
 };
-use raw_window_handle::{android::AndroidHandle, RawWindowHandle};
-use CreationError::OsError;
 
-pub type OsError = std::io::Error;
-
-pub struct EventLoop {
-    event_rx: Receiver<android_glue::Event>,
-    suspend_callback: RefCell<Option<Box<dyn Fn(bool) -> ()>>>,
+lazy_static! {
+    static ref CONFIG: RwLock<Configuration> = RwLock::new(Configuration::new());
 }
 
-#[derive(Clone)]
-pub struct EventLoopProxy;
+enum EventSource {
+    Callback,
+    InputQueue,
+    User,
+}
 
-impl EventLoop {
-    pub fn new() -> EventLoop {
-        let (tx, rx) = channel();
-        android_glue::add_sender(tx);
-        EventLoop {
-            event_rx: rx,
-            suspend_callback: Default::default(),
+fn poll(poll: Poll) -> Option<EventSource> {
+    match poll {
+        Poll::Event { data, .. } => match data as usize {
+            0 => Some(EventSource::Callback),
+            1 => Some(EventSource::InputQueue),
+            _ => unreachable!(),
+        },
+        Poll::Timeout => None,
+        Poll::Wake => Some(EventSource::User),
+        Poll::Callback => unreachable!(),
+    }
+}
+
+pub struct EventLoop<T: 'static> {
+    window_target: event_loop::EventLoopWindowTarget<T>,
+    user_queue: Arc<Mutex<VecDeque<T>>>,
+}
+
+impl<T: 'static> EventLoop<T> {
+    pub fn new() -> Self {
+        Self {
+            window_target: event_loop::EventLoopWindowTarget {
+                p: EventLoopWindowTarget {
+                    _marker: std::marker::PhantomData,
+                },
+                _marker: std::marker::PhantomData,
+            },
+            user_queue: Default::default(),
         }
     }
 
-    #[inline]
-    pub fn available_monitors(&self) -> VecDeque<MonitorHandle> {
-        let mut rb = VecDeque::with_capacity(1);
-        rb.push_back(MonitorHandle);
-        rb
+    pub fn run<F>(self, mut event_handler: F) -> !
+    where
+        F: 'static
+            + FnMut(event::Event<'_, T>, &event_loop::EventLoopWindowTarget<T>, &mut ControlFlow),
+    {
+        let mut cf = ControlFlow::default();
+        let mut first_event = None;
+        let mut start_cause = event::StartCause::Init;
+        let looper = ThreadLooper::for_thread().unwrap();
+        let mut running = false;
+
+        loop {
+            event_handler(
+                event::Event::NewEvents(start_cause),
+                self.window_target(),
+                &mut cf,
+            );
+
+            let mut redraw = false;
+            let mut resized = false;
+
+            match first_event.take() {
+                Some(EventSource::Callback) => match ndk_glue::poll_events().unwrap() {
+                    Event::WindowCreated => {
+                        event_handler(event::Event::Resumed, self.window_target(), &mut cf);
+                    }
+                    Event::WindowResized => resized = true,
+                    Event::WindowRedrawNeeded => redraw = true,
+                    Event::WindowDestroyed => {
+                        event_handler(event::Event::Suspended, self.window_target(), &mut cf);
+                    }
+                    Event::Pause => running = false,
+                    Event::Resume => running = true,
+                    Event::ConfigChanged => {
+                        let am = ndk_glue::native_activity().asset_manager();
+                        let config = Configuration::from_asset_manager(&am);
+                        let old_scale_factor = MonitorHandle.scale_factor();
+                        *CONFIG.write().unwrap() = config;
+                        let scale_factor = MonitorHandle.scale_factor();
+                        if (scale_factor - old_scale_factor).abs() < f64::EPSILON {
+                            let mut size = MonitorHandle.size();
+                            let event = event::Event::WindowEvent {
+                                window_id: window::WindowId(WindowId),
+                                event: event::WindowEvent::ScaleFactorChanged {
+                                    new_inner_size: &mut size,
+                                    scale_factor,
+                                },
+                            };
+                            event_handler(event, self.window_target(), &mut cf);
+                        }
+                    }
+                    _ => {}
+                },
+                Some(EventSource::InputQueue) => {
+                    if let Some(input_queue) = ndk_glue::input_queue().as_ref() {
+                        while let Some(event) = input_queue.get_event() {
+                            println!("event {:?}", event);
+                            if let Some(event) = input_queue.pre_dispatch(event) {
+                                let window_id = window::WindowId(WindowId);
+                                let device_id = event::DeviceId(DeviceId);
+                                match &event {
+                                    InputEvent::MotionEvent(motion_event) => {
+                                        let phase = match motion_event.action() {
+                                            MotionAction::Down => Some(event::TouchPhase::Started),
+                                            MotionAction::Up => Some(event::TouchPhase::Ended),
+                                            MotionAction::Move => Some(event::TouchPhase::Moved),
+                                            MotionAction::Cancel => {
+                                                Some(event::TouchPhase::Cancelled)
+                                            }
+                                            _ => None, // TODO mouse events
+                                        };
+                                        let pointer = motion_event.pointer_at_index(0);
+                                        let location = PhysicalPosition {
+                                            x: pointer.x() as _,
+                                            y: pointer.y() as _,
+                                        };
+
+                                        if let Some(phase) = phase {
+                                            let event = event::Event::WindowEvent {
+                                                window_id,
+                                                event: event::WindowEvent::Touch(event::Touch {
+                                                    device_id,
+                                                    phase,
+                                                    location,
+                                                    id: 0,
+                                                    force: None,
+                                                }),
+                                            };
+                                            event_handler(event, self.window_target(), &mut cf);
+                                        }
+                                    }
+                                    InputEvent::KeyEvent(_) => {} // TODO
+                                };
+                                input_queue.finish_event(event, true);
+                            }
+                        }
+                    }
+                }
+                Some(EventSource::User) => {
+                    let mut user_queue = self.user_queue.lock().unwrap();
+                    while let Some(event) = user_queue.pop_front() {
+                        event_handler(
+                            event::Event::UserEvent(event),
+                            self.window_target(),
+                            &mut cf,
+                        );
+                    }
+                }
+                None => {}
+            }
+
+            event_handler(
+                event::Event::MainEventsCleared,
+                self.window_target(),
+                &mut cf,
+            );
+
+            if resized && running {
+                let size = MonitorHandle.size();
+                let event = event::Event::WindowEvent {
+                    window_id: window::WindowId(WindowId),
+                    event: event::WindowEvent::Resized(size),
+                };
+                event_handler(event, self.window_target(), &mut cf);
+            }
+
+            if redraw && running {
+                let event = event::Event::RedrawRequested(window::WindowId(WindowId));
+                event_handler(event, self.window_target(), &mut cf);
+            }
+
+            event_handler(
+                event::Event::RedrawEventsCleared,
+                self.window_target(),
+                &mut cf,
+            );
+
+            match cf {
+                ControlFlow::Exit => panic!(),
+                ControlFlow::Poll => {
+                    start_cause = event::StartCause::Poll;
+                }
+                ControlFlow::Wait => {
+                    first_event = poll(looper.poll_all().unwrap());
+                    start_cause = event::StartCause::WaitCancelled {
+                        start: Instant::now(),
+                        requested_resume: None,
+                    }
+                }
+                ControlFlow::WaitUntil(instant) => {
+                    let start = Instant::now();
+                    let duration = if instant <= start {
+                        Duration::default()
+                    } else {
+                        instant - start
+                    };
+                    first_event = poll(looper.poll_all_timeout(duration).unwrap());
+                    start_cause = if first_event.is_some() {
+                        event::StartCause::WaitCancelled {
+                            start,
+                            requested_resume: Some(instant),
+                        }
+                    } else {
+                        event::StartCause::ResumeTimeReached {
+                            start,
+                            requested_resume: instant,
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    pub fn window_target(&self) -> &event_loop::EventLoopWindowTarget<T> {
+        &self.window_target
     }
 
-    #[inline]
     pub fn primary_monitor(&self) -> MonitorHandle {
         MonitorHandle
     }
 
-    pub fn poll_events<F>(&mut self, mut callback: F)
-    where
-        F: FnMut(::Event),
-    {
-        while let Ok(event) = self.event_rx.try_recv() {
-            let e = match event {
-                android_glue::Event::EventMotion(motion) => {
-                    let dpi_factor = MonitorHandle.scale_factor();
-                    let location = LogicalPosition::from_physical(
-                        (motion.x as f64, motion.y as f64),
-                        dpi_factor,
-                    );
-                    Some(Event::WindowEvent {
-                        window_id: RootWindowId(WindowId),
-                        event: WindowEvent::Touch(Touch {
-                            phase: match motion.action {
-                                android_glue::MotionAction::Down => TouchPhase::Started,
-                                android_glue::MotionAction::Move => TouchPhase::Moved,
-                                android_glue::MotionAction::Up => TouchPhase::Ended,
-                                android_glue::MotionAction::Cancel => TouchPhase::Cancelled,
-                            },
-                            location,
-                            force: None, // TODO
-                            id: motion.pointer_id as u64,
-                            device_id: DEVICE_ID,
-                        }),
-                    })
-                }
-                android_glue::Event::InitWindow => {
-                    // The activity went to foreground.
-                    if let Some(cb) = self.suspend_callback.borrow().as_ref() {
-                        (*cb)(false);
-                    }
-                    Some(Event::Resumed)
-                }
-                android_glue::Event::TermWindow => {
-                    // The activity went to background.
-                    if let Some(cb) = self.suspend_callback.borrow().as_ref() {
-                        (*cb)(true);
-                    }
-                    Some(Event::Suspended)
-                }
-                android_glue::Event::WindowResized | android_glue::Event::ConfigChanged => {
-                    // Activity Orientation changed or resized.
-                    let native_window = unsafe { android_glue::native_window() };
-                    if native_window.is_null() {
-                        None
-                    } else {
-                        let dpi_factor = MonitorHandle.scale_factor();
-                        let physical_size = MonitorHandle.size();
-                        let size = LogicalSize::from_physical(physical_size, dpi_factor);
-                        Some(Event::WindowEvent {
-                            window_id: RootWindowId(WindowId),
-                            event: WindowEvent::Resized(size),
-                        })
-                    }
-                }
-                android_glue::Event::WindowRedrawNeeded => {
-                    // The activity needs to be redrawn.
-                    Some(Event::WindowEvent {
-                        window_id: RootWindowId(WindowId),
-                        event: WindowEvent::Redraw,
-                    })
-                }
-                android_glue::Event::Wake => Some(Event::Awakened),
-                _ => None,
-            };
+    pub fn available_monitors(&self) -> VecDeque<MonitorHandle> {
+        let mut v = VecDeque::with_capacity(1);
+        v.push_back(self.primary_monitor());
+        v
+    }
 
-            if let Some(event) = e {
-                callback(event);
-            }
+    pub fn create_proxy(&self) -> EventLoopProxy<T> {
+        EventLoopProxy {
+            queue: self.user_queue.clone(),
+            looper: ForeignLooper::for_thread().expect("called from event loop thread"),
         }
     }
-
-    pub fn set_suspend_callback(&self, cb: Option<Box<dyn Fn(bool) -> ()>>) {
-        *self.suspend_callback.borrow_mut() = cb;
-    }
-
-    pub fn run_forever<F>(&mut self, mut callback: F)
-    where
-        F: FnMut(::Event) -> ::ControlFlow,
-    {
-        // Yeah that's a very bad implementation.
-        loop {
-            let mut control_flow = ::ControlFlow::Continue;
-            self.poll_events(|e| {
-                if let ::ControlFlow::Break = callback(e) {
-                    control_flow = ::ControlFlow::Break;
-                }
-            });
-            if let ::ControlFlow::Break = control_flow {
-                break;
-            }
-            ::std::thread::sleep(::std::time::Duration::from_millis(5));
-        }
-    }
-
-    pub fn create_proxy(&self) -> EventLoopProxy {
-        EventLoopProxy
-    }
 }
 
-impl EventLoopProxy {
-    pub fn wakeup(&self) -> Result<(), ::EventLoopClosed<()>> {
-        android_glue::wake_event_loop();
+pub struct EventLoopProxy<T: 'static> {
+    queue: Arc<Mutex<VecDeque<T>>>,
+    looper: ForeignLooper,
+}
+
+impl<T> EventLoopProxy<T> {
+    pub fn send_event(&self, event: T) -> Result<(), event_loop::EventLoopClosed<T>> {
+        self.queue.lock().unwrap().push_back(event);
+        self.looper.wake();
         Ok(())
     }
 }
 
-#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+impl<T> Clone for EventLoopProxy<T> {
+    fn clone(&self) -> Self {
+        EventLoopProxy {
+            queue: self.queue.clone(),
+            looper: self.looper.clone(),
+        }
+    }
+}
+
+pub struct EventLoopWindowTarget<T: 'static> {
+    _marker: std::marker::PhantomData<T>,
+}
+
+#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
 pub struct WindowId;
 
 impl WindowId {
-    pub unsafe fn dummy() -> Self {
+    pub fn dummy() -> Self {
         WindowId
     }
 }
 
-#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
 pub struct DeviceId;
 
 impl DeviceId {
-    pub unsafe fn dummy() -> Self {
+    pub fn dummy() -> Self {
         DeviceId
     }
 }
 
-pub struct Window {
-    native_window: *const c_void,
-}
-
-#[derive(Clone)]
-pub struct MonitorHandle;
-
-impl fmt::Debug for MonitorHandle {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        #[derive(Debug)]
-        struct MonitorHandle {
-            name: Option<String>,
-            dimensions: PhysicalSize<u32>,
-            position: PhysicalPosition<i32>,
-            scale_factor: f64,
-        }
-
-        let monitor_id_proxy = MonitorHandle {
-            name: self.name(),
-            dimensions: self.size(),
-            position: self.outer_position(),
-            scale_factor: self.scale_factor(),
-        };
-
-        monitor_id_proxy.fmt(f)
-    }
-}
-
-impl MonitorHandle {
-    #[inline]
-    pub fn name(&self) -> Option<String> {
-        Some("Primary".to_string())
-    }
-
-    #[inline]
-    pub fn size(&self) -> PhysicalSize<u32> {
-        unsafe {
-            let window = android_glue::native_window();
-            (
-                ffi::ANativeWindow_getWidth(window) as f64,
-                ffi::ANativeWindow_getHeight(window) as f64,
-            )
-                .into()
-        }
-    }
-
-    #[inline]
-    pub fn outer_position(&self) -> PhysicalPosition<i32> {
-        // Android assumes single screen
-        (0, 0).into()
-    }
-
-    #[inline]
-    pub fn scale_factor(&self) -> f64 {
-        1.0
-    }
-}
-
-#[derive(Clone, Default)]
+#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
 pub struct PlatformSpecificWindowBuilderAttributes;
-#[derive(Clone, Default)]
-pub struct PlatformSpecificHeadlessBuilderAttributes;
+
+pub struct Window;
 
 impl Window {
-    pub fn new(
-        _: &EventLoop,
-        win_attribs: WindowAttributes,
+    pub fn new<T: 'static>(
+        _el: &EventLoopWindowTarget<T>,
+        _window_attrs: window::WindowAttributes,
         _: PlatformSpecificWindowBuilderAttributes,
-    ) -> Result<Window, CreationError> {
-        let native_window = unsafe { android_glue::native_window() };
-        if native_window.is_null() {
-            return Err(OsError(format!("Android's native window is null")));
-        }
-
-        android_glue::set_multitouch(true);
-
-        Ok(Window {
-            native_window: native_window as *const _,
-        })
+    ) -> Result<Self, error::OsError> {
+        // FIXME this ignores requested window attributes
+        Ok(Self)
     }
 
-    #[inline]
-    pub fn native_window(&self) -> *const c_void {
-        self.native_window
-    }
-
-    #[inline]
-    pub fn set_title(&self, _: &str) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn show(&self) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn hide(&self) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn outer_position(&self) -> Option<LogicalPosition<f64>> {
-        // N/A
-        None
-    }
-
-    #[inline]
-    pub fn inner_position(&self) -> Option<LogicalPosition<f64>> {
-        // N/A
-        None
-    }
-
-    #[inline]
-    pub fn set_outer_position(&self, _position: LogicalPosition<f64>) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn set_min_inner_size(&self, _dimensions: Option<LogicalSize<f64>>) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn set_max_inner_size(&self, _dimensions: Option<LogicalSize<f64>>) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn set_resizable(&self, _resizable: bool) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn inner_size(&self) -> Option<LogicalSize<f64>> {
-        if self.native_window.is_null() {
-            None
-        } else {
-            let dpi_factor = self.scale_factor();
-            let physical_size = self.current_monitor().size();
-            Some(LogicalSize::from_physical(physical_size, dpi_factor))
-        }
-    }
-
-    #[inline]
-    pub fn outer_size(&self) -> Option<LogicalSize<f64>> {
-        self.inner_size()
-    }
-
-    #[inline]
-    pub fn set_inner_size(&self, _size: LogicalSize<f64>) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn scale_factor(&self) -> f64 {
-        self.current_monitor().scale_factor()
-    }
-
-    #[inline]
-    pub fn set_cursor_icon(&self, _: CursorIcon) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn set_cursor_grab(&self, _grab: bool) -> Result<(), ExternalError> {
-        Err(ExternalError::NotSupported(NotSupportedError::new()))
-    }
-
-    #[inline]
-    pub fn hide_cursor(&self, _hide: bool) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn set_cursor_position(
-        &self,
-        _position: LogicalPosition<f64>,
-    ) -> Result<(), ExternalError> {
-        Err(ExternalError::NotSupported(NotSupportedError::new()))
-    }
-
-    #[inline]
-    pub fn set_minimized(&self, _minimized: bool) {
-        unimplemented!()
-    }
-
-    #[inline]
-    pub fn set_maximized(&self, _maximized: bool) {
-        // N/A
-        // Android has single screen maximized apps so nothing to do
-    }
-
-    #[inline]
-    pub fn fullscreen(&self) -> Option<RootMonitorHandle> {
-        // N/A
-        // Android has single screen maximized apps so nothing to do
-        None
-    }
-
-    #[inline]
-    pub fn set_fullscreen(&self, _monitor: Option<RootMonitorHandle>) {
-        // N/A
-        // Android has single screen maximized apps so nothing to do
-    }
-
-    #[inline]
-    pub fn set_decorations(&self, _decorations: bool) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn set_always_on_top(&self, _always_on_top: bool) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn set_window_icon(&self, _icon: Option<::Icon>) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn set_ime_position(&self, _spot: LogicalPosition<f64>) {
-        // N/A
-    }
-
-    #[inline]
-    pub fn current_monitor(&self) -> RootMonitorHandle {
-        RootMonitorHandle {
-            inner: MonitorHandle,
-        }
-    }
-
-    #[inline]
-    pub fn available_monitors(&self) -> VecDeque<MonitorHandle> {
-        let mut rb = VecDeque::with_capacity(1);
-        rb.push_back(MonitorHandle);
-        rb
-    }
-
-    #[inline]
-    pub fn primary_monitor(&self) -> MonitorHandle {
-        MonitorHandle
-    }
-
-    #[inline]
     pub fn id(&self) -> WindowId {
         WindowId
     }
 
-    #[inline]
-    pub fn raw_window_handle(&self) -> RawWindowHandle {
-        let handle = AndroidHandle {
-            a_native_window: self.native_window,
-            ..WindowsHandle::empty()
+    pub fn primary_monitor(&self) -> MonitorHandle {
+        MonitorHandle
+    }
+
+    pub fn available_monitors(&self) -> VecDeque<MonitorHandle> {
+        let mut v = VecDeque::with_capacity(1);
+        v.push_back(MonitorHandle);
+        v
+    }
+
+    pub fn current_monitor(&self) -> monitor::MonitorHandle {
+        monitor::MonitorHandle {
+            inner: MonitorHandle,
+        }
+    }
+
+    pub fn scale_factor(&self) -> f64 {
+        MonitorHandle.scale_factor()
+    }
+
+    pub fn request_redraw(&self) {
+        // TODO
+    }
+
+    pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, error::NotSupportedError> {
+        Err(error::NotSupportedError::new())
+    }
+
+    pub fn outer_position(&self) -> Result<PhysicalPosition<i32>, error::NotSupportedError> {
+        Err(error::NotSupportedError::new())
+    }
+
+    pub fn set_outer_position(&self, _position: Position) {
+        // no effect
+    }
+
+    pub fn inner_size(&self) -> PhysicalSize<u32> {
+        self.outer_size()
+    }
+
+    pub fn set_inner_size(&self, _size: Size) {
+        panic!("Cannot set window size on Android");
+    }
+
+    pub fn outer_size(&self) -> PhysicalSize<u32> {
+        MonitorHandle.size()
+    }
+
+    pub fn set_min_inner_size(&self, _: Option<Size>) {}
+
+    pub fn set_max_inner_size(&self, _: Option<Size>) {}
+
+    pub fn set_title(&self, _title: &str) {}
+
+    pub fn set_visible(&self, _visibility: bool) {}
+
+    pub fn set_resizable(&self, _resizeable: bool) {}
+
+    pub fn set_minimized(&self, _minimized: bool) {}
+
+    pub fn set_maximized(&self, _maximized: bool) {}
+
+    pub fn set_fullscreen(&self, _monitor: Option<window::Fullscreen>) {
+        panic!("Cannot set fullscreen on Android");
+    }
+
+    pub fn fullscreen(&self) -> Option<window::Fullscreen> {
+        None
+    }
+
+    pub fn set_decorations(&self, _decorations: bool) {}
+
+    pub fn set_always_on_top(&self, _always_on_top: bool) {}
+
+    pub fn set_window_icon(&self, _window_icon: Option<crate::icon::Icon>) {}
+
+    pub fn set_ime_position(&self, _position: Position) {}
+
+    pub fn set_cursor_icon(&self, _: window::CursorIcon) {}
+
+    pub fn set_cursor_position(&self, _: Position) -> Result<(), error::ExternalError> {
+        Err(error::ExternalError::NotSupported(
+            error::NotSupportedError::new(),
+        ))
+    }
+
+    pub fn set_cursor_grab(&self, _: bool) -> Result<(), error::ExternalError> {
+        Err(error::ExternalError::NotSupported(
+            error::NotSupportedError::new(),
+        ))
+    }
+
+    pub fn set_cursor_visible(&self, _: bool) {}
+
+    pub fn raw_window_handle(&self) -> raw_window_handle::RawWindowHandle {
+        let a_native_window = if let Some(native_window) = ndk_glue::native_window().as_ref() {
+            unsafe { native_window.ptr().as_mut() as *mut _ as *mut _ }
+        } else {
+            panic!("native window null");
         };
-        RawWindowHandle::Android(handle)
+        let mut handle = raw_window_handle::android::AndroidHandle::empty();
+        handle.a_native_window = a_native_window;
+        raw_window_handle::RawWindowHandle::Android(handle)
+    }
+
+    pub fn config(&self) -> Configuration {
+        CONFIG.read().unwrap().clone()
+    }
+
+    pub fn content_rect(&self) -> Rect {
+        ndk_glue::content_rect()
     }
 }
 
-unsafe impl Send for Window {}
-unsafe impl Sync for Window {}
+#[derive(Default, Clone, Debug)]
+pub struct OsError;
 
-// Constant device ID, to be removed when this backend is updated to report real device IDs.
-const DEVICE_ID: ::DeviceId = ::DeviceId(DeviceId);
+use std::fmt::{self, Display, Formatter};
+impl Display for OsError {
+    fn fmt(&self, fmt: &mut Formatter<'_>) -> Result<(), fmt::Error> {
+        write!(fmt, "Android OS Error")
+    }
+}
+
+pub(crate) use crate::icon::NoIcon as PlatformIcon;
+
+#[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub struct MonitorHandle;
+
+impl MonitorHandle {
+    pub fn name(&self) -> Option<String> {
+        Some("Android Device".to_owned())
+    }
+
+    pub fn size(&self) -> PhysicalSize<u32> {
+        if let Some(native_window) = ndk_glue::native_window().as_ref() {
+            let width = native_window.width() as _;
+            let height = native_window.height() as _;
+            PhysicalSize::new(width, height)
+        } else {
+            PhysicalSize::new(0, 0)
+        }
+    }
+
+    pub fn position(&self) -> PhysicalPosition<i32> {
+        (0, 0).into()
+    }
+
+    pub fn scale_factor(&self) -> f64 {
+        let config = CONFIG.read().unwrap();
+        config
+            .density()
+            .map(|dpi| dpi as f64 / 160.0)
+            .unwrap_or(1.0)
+    }
+
+    pub fn video_modes(&self) -> impl Iterator<Item = monitor::VideoMode> {
+        let size = self.size().into();
+        let mut v = Vec::new();
+        // FIXME this is not the real refresh rate
+        // (it is guarunteed to support 32 bit color though)
+        v.push(monitor::VideoMode {
+            video_mode: VideoMode {
+                size,
+                bit_depth: 32,
+                refresh_rate: 60,
+                monitor: self.clone(),
+            },
+        });
+        v.into_iter()
+    }
+}
+
+#[derive(Clone, Debug, Eq, Hash, PartialEq)]
+pub struct VideoMode {
+    size: (u32, u32),
+    bit_depth: u16,
+    refresh_rate: u16,
+    monitor: MonitorHandle,
+}
+
+impl VideoMode {
+    pub fn size(&self) -> PhysicalSize<u32> {
+        self.size.into()
+    }
+
+    pub fn bit_depth(&self) -> u16 {
+        self.bit_depth
+    }
+
+    pub fn refresh_rate(&self) -> u16 {
+        self.refresh_rate
+    }
+
+    pub fn monitor(&self) -> monitor::MonitorHandle {
+        monitor::MonitorHandle {
+            inner: self.monitor.clone(),
+        }
+    }
+}

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/view.rs

@@ -6,6 +6,7 @@ use objc::{
 };
 
 use crate::{
+    dpi::PhysicalPosition,
     event::{DeviceId as RootDeviceId, Event, Force, Touch, TouchPhase, WindowEvent},
     platform::ios::MonitorHandleExtIOS,
     platform_impl::platform::{
@@ -127,12 +128,12 @@ 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 dpi_factor: CGFloat = msg_send![screen, scale];
+                let scale_factor: CGFloat = msg_send![screen, scale];
                 let size = crate::dpi::LogicalSize {
                     width: screen_frame.size.width as f64,
                     height: screen_frame.size.height as f64,
                 }
-                .to_physical(dpi_factor.into());
+                .to_physical(scale_factor.into());
                 app_state::handle_nonuser_event(EventWrapper::StaticEvent(Event::WindowEvent {
                     window_id: RootWindowId(window.into()),
                     event: WindowEvent::Resized(size),
@@ -162,15 +163,15 @@ 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 dpi_factor: CGFloat = msg_send![object, contentScaleFactor];
+                let scale_factor: CGFloat = msg_send![object, contentScaleFactor];
                 assert!(
-                    !dpi_factor.is_nan()
-                        && dpi_factor.is_finite()
-                        && dpi_factor.is_sign_positive()
-                        && dpi_factor > 0.0,
+                    !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 = dpi_factor.into();
+                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];
@@ -209,7 +210,7 @@ unsafe fn get_view_class(root_view_class: &'static Class) -> &'static Class {
                     if touch == nil {
                         break;
                     }
-                    let location: CGPoint = msg_send![touch, locationInView: nil];
+                    let logical_location: CGPoint = msg_send![touch, locationInView: nil];
                     let touch_type: UITouchType = msg_send![touch, type];
                     let force = if os_supports_force {
                         let trait_collection: id = msg_send![object, traitCollection];
@@ -248,12 +249,19 @@ unsafe fn get_view_class(root_view_class: &'static Class) -> &'static Class {
                         _ => panic!("unexpected touch phase: {:?}", phase as i32),
                     };
 
+                    let physical_location = {
+                        let scale_factor: CGFloat = msg_send![object, contentScaleFactor];
+                        PhysicalPosition::from_logical::<(f64, f64), f64>(
+                            (logical_location.x as _, logical_location.y as _),
+                            scale_factor,
+                        )
+                    };
                     touch_events.push(EventWrapper::StaticEvent(Event::WindowEvent {
                         window_id: RootWindowId(window.into()),
                         event: WindowEvent::Touch(Touch {
                             device_id: RootDeviceId(DeviceId { uiscreen }),
                             id: touch_id,
-                            location: (location.x as f64, location.y as f64).into(),
+                            location: physical_location,
                             force,
                             phase,
                         }),

src/platform_impl/ios/window.rs

@@ -83,8 +83,8 @@ impl Inner {
                 x: safe_area.origin.x as f64,
                 y: safe_area.origin.y as f64,
             };
-            let dpi_factor = self.scale_factor();
-            Ok(position.to_physical(dpi_factor))
+            let scale_factor = self.scale_factor();
+            Ok(position.to_physical(scale_factor))
         }
     }
 
@@ -95,15 +95,15 @@ impl Inner {
                 x: screen_frame.origin.x as f64,
                 y: screen_frame.origin.y as f64,
             };
-            let dpi_factor = self.scale_factor();
-            Ok(position.to_physical(dpi_factor))
+            let scale_factor = self.scale_factor();
+            Ok(position.to_physical(scale_factor))
         }
     }
 
     pub fn set_outer_position(&self, physical_position: Position) {
         unsafe {
-            let dpi_factor = self.scale_factor();
-            let position = physical_position.to_logical::<f64>(dpi_factor);
+            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 {
@@ -119,25 +119,25 @@ impl Inner {
 
     pub fn inner_size(&self) -> PhysicalSize<u32> {
         unsafe {
-            let dpi_factor = self.scale_factor();
+            let scale_factor = self.scale_factor();
             let safe_area = self.safe_area_screen_space();
             let size = LogicalSize {
                 width: safe_area.size.width as f64,
                 height: safe_area.size.height as f64,
             };
-            size.to_physical(dpi_factor)
+            size.to_physical(scale_factor)
         }
     }
 
     pub fn outer_size(&self) -> PhysicalSize<u32> {
         unsafe {
-            let dpi_factor = self.scale_factor();
+            let scale_factor = self.scale_factor();
             let screen_frame = self.screen_frame();
             let size = LogicalSize {
                 width: screen_frame.size.width as f64,
                 height: screen_frame.size.height as f64,
             };
-            size.to_physical(dpi_factor)
+            size.to_physical(scale_factor)
         }
     }
 
@@ -355,8 +355,8 @@ impl Window {
 
             let frame = match window_attributes.inner_size {
                 Some(dim) => {
-                    let dpi_factor = msg_send![screen, scale];
-                    let size = dim.to_logical::<f64>(dpi_factor);
+                    let scale_factor = msg_send![screen, scale];
+                    let size = dim.to_logical::<f64>(scale_factor);
                     CGRect {
                         origin: screen_bounds.origin,
                         size: CGSize {
@@ -400,8 +400,8 @@ impl Window {
 
             // Like the Windows and macOS backends, we send a `ScaleFactorChanged` and `Resized`
             // event on window creation if the DPI factor != 1.0
-            let dpi_factor: CGFloat = msg_send![view, contentScaleFactor];
-            let scale_factor: f64 = dpi_factor.into();
+            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];

src/platform_impl/linux/mod.rs

@@ -18,6 +18,8 @@ use crate::{
     window::{CursorIcon, Fullscreen, WindowAttributes},
 };
 
+pub(crate) use crate::icon::RgbaIcon as PlatformIcon;
+
 pub mod wayland;
 pub mod x11;
 
@@ -61,7 +63,7 @@ impl Default for PlatformSpecificWindowBuilderAttributes {
 
 lazy_static! {
     pub static ref X11_BACKEND: Mutex<Result<Arc<XConnection>, XNotSupported>> =
-        { Mutex::new(XConnection::new(Some(x_error_callback)).map(Arc::new)) };
+        Mutex::new(XConnection::new(Some(x_error_callback)).map(Arc::new));
 }
 
 #[derive(Debug, Clone)]
@@ -584,13 +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]

src/platform_impl/linux/wayland/event_loop.rs

@@ -39,7 +39,10 @@ use crate::{
     window::{CursorIcon, WindowId as RootWindowId},
 };
 
-use super::{window::WindowStore, DeviceId, WindowId};
+use super::{
+    window::{DecorationsAction, WindowStore},
+    DeviceId, WindowId,
+};
 
 use smithay_client_toolkit::{
     output::OutputMgr,
@@ -90,6 +93,7 @@ pub struct CursorManager {
     locked_pointers: Vec<ZwpLockedPointerV1>,
     cursor_visible: bool,
     current_cursor: CursorIcon,
+    scale_factor: u32,
 }
 
 impl CursorManager {
@@ -101,6 +105,7 @@ impl CursorManager {
             locked_pointers: Vec::new(),
             cursor_visible: true,
             current_cursor: CursorIcon::default(),
+            scale_factor: 1,
         }
     }
 
@@ -145,6 +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",
@@ -193,7 +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);
         }
     }
 
@@ -704,47 +714,70 @@ impl<T> EventLoop<T> {
         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((w, h)) = window.newsize {
-                    // 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 (w, h) != *window.size {
-                        let logical_size = crate::dpi::LogicalSize::new(w as f64, h as f64);
-                        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 {
-                    let dpi = dpi as f64;
-                    let logical_size = LogicalSize::<f64>::from(*window.size);
-                    let mut new_inner_size = logical_size.to_physical(dpi);
+            // Update window logical .size field (for callbacks using .inner_size)
+            let (old_logical_size, mut logical_size) = {
+                let mut window_size = window.size.lock().unwrap();
+                let old_logical_size = *window_size;
+                *window_size = window.new_size.unwrap_or(old_logical_size);
+                (old_logical_size, *window_size)
+            };
 
+            if let Some(scale_factor) = window.new_scale_factor {
+                // Update cursor scale factor
+                self.cursor_manager
+                    .lock()
+                    .unwrap()
+                    .update_scale_factor(scale_factor as u32);
+                let new_logical_size = {
+                    let scale_factor = scale_factor as f64;
+                    let mut physical_size =
+                        LogicalSize::<f64>::from(logical_size).to_physical(scale_factor);
                     callback(Event::WindowEvent {
                         window_id,
                         event: WindowEvent::ScaleFactorChanged {
-                            scale_factor: dpi,
-                            new_inner_size: &mut new_inner_size,
+                            scale_factor,
+                            new_inner_size: &mut physical_size,
                         },
                     });
-
-                    let (w, h) = new_inner_size.to_logical::<u32>(dpi).into();
-                    frame.resize(w, h);
-                    *window.size = (w, h);
+                    physical_size.to_logical::<u32>(scale_factor).into()
+                };
+                // Update size if changed by callback
+                if new_logical_size != logical_size {
+                    logical_size = new_logical_size;
+                    *window.size.lock().unwrap() = logical_size.into();
                 }
             }
+
+            if window.new_size.is_some() || window.new_scale_factor.is_some() {
+                if let Some(frame) = window.frame {
+                    // 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.
+                    let (w, h) = logical_size;
+                    frame.resize(w, h);
+                    frame.refresh();
+                }
+                // Don't send resize event downstream if the new logical size and scale is identical to the
+                // current one
+                if logical_size != old_logical_size || window.new_scale_factor.is_some() {
+                    let physical_size = LogicalSize::<f64>::from(logical_size).to_physical(
+                        window.new_scale_factor.unwrap_or(window.prev_scale_factor) as f64,
+                    );
+                    callback(Event::WindowEvent {
+                        window_id,
+                        event: WindowEvent::Resized(physical_size),
+                    });
+                }
+            }
+
             if window.closed {
                 callback(Event::WindowEvent {
                     window_id,

src/platform_impl/linux/wayland/keyboard.rs

@@ -8,9 +8,7 @@ use smithay_client_toolkit::{
     reexports::client::protocol::{wl_keyboard, wl_seat},
 };
 
-use crate::event::{
-    DeviceEvent, ElementState, KeyboardInput, ModifiersState, VirtualKeyCode, WindowEvent,
-};
+use crate::event::{ElementState, KeyboardInput, ModifiersState, VirtualKeyCode, WindowEvent};
 
 pub fn init_keyboard(
     seat: &wl_seat::WlSeat,
@@ -33,9 +31,24 @@ pub fn init_keyboard(
                     let wid = make_wid(&surface);
                     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);
+                    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;
                 }
@@ -88,7 +101,9 @@ pub fn init_keyboard(
 
                     *modifiers_tracker.lock().unwrap() = modifiers;
 
-                    my_sink.send_device_event(DeviceEvent::ModifiersChanged(modifiers), DeviceId);
+                    if let Some(wid) = *target.lock().unwrap() {
+                        my_sink.send_window_event(WindowEvent::ModifiersChanged(modifiers), wid);
+                    }
                 }
             }
         },

src/platform_impl/linux/wayland/pointer.rs

@@ -1,5 +1,6 @@
 use std::sync::{Arc, Mutex};
 
+use crate::dpi::LogicalPosition;
 use crate::event::{
     DeviceEvent, ElementState, ModifiersState, MouseButton, MouseScrollDelta, TouchPhase,
     WindowEvent,
@@ -76,13 +77,16 @@ pub fn implement_pointer(
                                 },
                                 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 * scale_factor, surface_y * scale_factor)
-                                        .into(),
+                                    position,
                                     modifiers: modifiers_tracker.lock().unwrap().clone(),
                                 },
                                 wid,
@@ -109,15 +113,18 @@ pub fn implement_pointer(
                         ..
                     } => {
                         if let Some(surface) = mouse_focus.as_ref() {
-                            let scale_factor = surface::get_dpi_factor(&surface) as f64;
                             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 * scale_factor, surface_y * scale_factor)
-                                        .into(),
+                                    position,
                                     modifiers: modifiers_tracker.lock().unwrap().clone(),
                                 },
                                 wid,

src/platform_impl/linux/wayland/touch.rs

@@ -1,17 +1,22 @@
 use std::sync::{Arc, Mutex};
 
+use crate::dpi::LogicalPosition;
 use crate::event::{TouchPhase, WindowEvent};
 
-use super::{event_loop::EventsSink, 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,
 }
 
@@ -31,21 +36,24 @@ pub(crate) fn implement_touch(
                     } => {
                         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,
                             });
                         }
@@ -54,52 +62,63 @@ pub(crate) fn implement_touch(
                         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

@@ -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 {
@@ -52,15 +59,20 @@ impl Window {
         // 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| {
-            window_store.lock().unwrap().dpi_change(&surface, dpi);
-            surface.set_buffer_scale(dpi);
+        let surface = evlp.env.create_surface(move |scale_factor, surface| {
+            window_store
+                .lock()
+                .unwrap()
+                .scale_factor_change(&surface, scale_factor);
+            surface.set_buffer_scale(scale_factor);
         });
 
-        let dpi = get_dpi_factor(&surface) as f64;
+        // Always 1.
+        let scale_factor = get_dpi_factor(&surface);
+
         let (width, height) = attributes
             .inner_size
-            .map(|size| size.to_logical::<f64>(dpi).into())
+            .map(|size| size.to_logical::<f64>(scale_factor as f64).into())
             .unwrap_or((800, 600));
 
         // Create the window
@@ -69,6 +81,9 @@ impl Window {
 
         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,
@@ -81,9 +96,25 @@ impl Window {
 
                     for window in &mut store.windows {
                         if window.surface.as_ref().equals(&my_surface.as_ref()) {
-                            window.newsize = new_size;
+                            window.new_size = 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;
                         }
@@ -147,12 +178,12 @@ impl Window {
         frame.set_min_size(
             attributes
                 .min_inner_size
-                .map(|size| size.to_logical::<f64>(dpi).into()),
+                .map(|size| size.to_logical::<f64>(scale_factor as f64).into()),
         );
         frame.set_max_size(
             attributes
                 .max_inner_size
-                .map(|size| size.to_logical::<f64>(dpi).into()),
+                .map(|size| size.to_logical::<f64>(scale_factor as f64).into()),
         );
 
         let kill_switch = Arc::new(Mutex::new(false));
@@ -163,7 +194,7 @@ impl Window {
 
         evlp.store.lock().unwrap().windows.push(InternalWindow {
             closed: false,
-            newsize: None,
+            new_size: None,
             size: size.clone(),
             need_refresh: need_refresh.clone(),
             fullscreen: fullscreen.clone(),
@@ -172,8 +203,10 @@ impl Window {
             surface: surface.clone(),
             kill_switch: kill_switch.clone(),
             frame: Arc::downgrade(&frame),
-            current_dpi: 1,
-            new_dpi: None,
+            current_scale_factor: scale_factor,
+            new_scale_factor: None,
+            decorated: decorated.clone(),
+            pending_decorations_action: pending_decorations_action.clone(),
         });
         evlp.evq.borrow_mut().sync_roundtrip().unwrap();
 
@@ -189,6 +222,7 @@ impl Window {
             cursor_manager,
             fullscreen,
             cursor_grab_changed,
+            decorated,
         })
     }
 
@@ -221,9 +255,9 @@ impl Window {
     }
 
     pub fn inner_size(&self) -> PhysicalSize<u32> {
-        let dpi = self.scale_factor() as f64;
+        let scale_factor = self.scale_factor() as f64;
         let size = LogicalSize::<f64>::from(*self.size.lock().unwrap());
-        size.to_physical(dpi)
+        size.to_physical(scale_factor)
     }
 
     pub fn request_redraw(&self) {
@@ -232,38 +266,38 @@ impl Window {
 
     #[inline]
     pub fn outer_size(&self) -> PhysicalSize<u32> {
-        let dpi = self.scale_factor() as f64;
+        let scale_factor = 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);
         let size = LogicalSize::<f64>::from((w, h));
-        size.to_physical(dpi)
+        size.to_physical(scale_factor)
     }
 
     #[inline]
     // NOTE: This will only resize the borders, the contents must be updated by the user
     pub fn set_inner_size(&self, size: Size) {
-        let dpi = self.scale_factor() as f64;
-        let (w, h) = size.to_logical::<u32>(dpi).into();
+        let scale_factor = self.scale_factor() as f64;
+        let (w, h) = size.to_logical::<u32>(scale_factor).into();
         self.frame.lock().unwrap().resize(w, h);
         *(self.size.lock().unwrap()) = (w, h);
     }
 
     #[inline]
     pub fn set_min_inner_size(&self, dimensions: Option<Size>) {
-        let dpi = self.scale_factor() as f64;
+        let scale_factor = self.scale_factor() as f64;
         self.frame
             .lock()
             .unwrap()
-            .set_min_size(dimensions.map(|dim| dim.to_logical::<f64>(dpi).into()));
+            .set_min_size(dimensions.map(|dim| dim.to_logical::<f64>(scale_factor).into()));
     }
 
     #[inline]
     pub fn set_max_inner_size(&self, dimensions: Option<Size>) {
-        let dpi = self.scale_factor() as f64;
+        let scale_factor = self.scale_factor() as f64;
         self.frame
             .lock()
             .unwrap()
-            .set_max_size(dimensions.map(|dim| dim.to_logical::<f64>(dpi).into()));
+            .set_max_size(dimensions.map(|dim| dim.to_logical::<f64>(scale_factor).into()));
     }
 
     #[inline]
@@ -277,6 +311,7 @@ impl Window {
     }
 
     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;
     }
@@ -398,7 +433,7 @@ impl Drop for Window {
 struct InternalWindow {
     surface: wl_surface::WlSurface,
     // TODO: CONVERT TO LogicalSize<u32>s
-    newsize: Option<(u32, u32)>,
+    new_size: Option<(u32, u32)>,
     size: Arc<Mutex<(u32, u32)>>,
     need_refresh: Arc<Mutex<bool>>,
     fullscreen: Arc<Mutex<bool>>,
@@ -407,8 +442,10 @@ struct InternalWindow {
     closed: bool,
     kill_switch: Arc<Mutex<bool>>,
     frame: Weak<Mutex<SWindow<ConceptFrame>>>,
-    current_dpi: i32,
-    new_dpi: Option<i32>,
+    current_scale_factor: i32,
+    new_scale_factor: Option<i32>,
+    decorated: Arc<Mutex<bool>>,
+    pending_decorations_action: Arc<Mutex<Option<DecorationsAction>>>,
 }
 
 pub struct WindowStore {
@@ -416,15 +453,16 @@ 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 new_size: Option<(u32, u32)>,
+    pub size: &'a Mutex<(u32, u32)>,
+    pub prev_scale_factor: i32,
+    pub new_scale_factor: 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 {
@@ -466,10 +504,11 @@ impl WindowStore {
         }
     }
 
-    fn dpi_change(&mut self, surface: &wl_surface::WlSurface, new: i32) {
+    fn scale_factor_change(&mut self, surface: &wl_surface::WlSurface, new: i32) {
         for window in &mut self.windows {
             if surface.as_ref().equals(&window.surface.as_ref()) {
-                window.new_dpi = Some(new);
+                window.new_scale_factor = Some(new);
+                *(window.need_refresh.lock().unwrap()) = true;
             }
         }
     }
@@ -479,24 +518,25 @@ impl WindowStore {
         F: FnMut(WindowStoreForEach<'_>),
     {
         for window in &mut self.windows {
+            let prev_scale_factor = window.current_scale_factor;
+            if let Some(scale_factor) = window.new_scale_factor {
+                window.current_scale_factor = scale_factor;
+            }
             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 size,
-                prev_dpi: window.current_dpi,
-                new_dpi: window.new_dpi,
+                new_size: window.new_size.take(),
+                size: &window.size,
+                prev_scale_factor,
+                new_scale_factor: window.new_scale_factor.take(),
                 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;
-            }
             // avoid re-spamming the event
             window.closed = false;
         }

src/platform_impl/linux/x11/event_processor.rs

@@ -32,6 +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> {
@@ -136,11 +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),
+                                });
+                            }
                         }
                     }
                 }
@@ -872,44 +875,58 @@ impl<T: 'static> EventProcessor<T> {
                     ffi::XI_FocusIn => {
                         let xev: &ffi::XIFocusInEvent = unsafe { &*(xev.data as *const _) };
 
-                        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 = PhysicalPosition::new(xev.event_x, xev.event_y);
+                            let window_id = mkwid(xev.event);
+                            let position = PhysicalPosition::new(xev.event_x, xev.event_y);
 
-                        callback(Event::WindowEvent {
-                            window_id,
-                            event: CursorMoved {
-                                device_id: mkdid(pointer_id),
-                                position,
-                                modifiers,
-                            },
-                        });
+                            callback(Event::WindowEvent {
+                                window_id,
+                                event: Focused(true),
+                            });
 
-                        // Issue key press events for all pressed keys
-                        self.handle_pressed_keys(window_id, ElementState::Pressed, &mut callback);
+                            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 _) };
@@ -921,15 +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 => {
@@ -1084,10 +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),
+                                    });
+                                }
                             }
                         }
                     }

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

@@ -29,6 +29,7 @@ use std::{
     mem::{self, MaybeUninit},
     ops::Deref,
     os::raw::*,
+    ptr,
     rc::Rc,
     slice,
     sync::{mpsc, Arc, Mutex, Weak},
@@ -105,7 +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));
@@ -206,6 +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
@@ -248,14 +268,16 @@ impl<T: 'static> EventLoop<T> {
     {
         let mut control_flow = ControlFlow::default();
         let mut events = Events::with_capacity(8);
-
-        callback(
-            crate::event::Event::NewEvents(crate::event::StartCause::Init),
-            &self.target,
-            &mut control_flow,
-        );
+        let mut cause = StartCause::Init;
 
         loop {
+            sticky_exit_callback(
+                crate::event::Event::NewEvents(cause),
+                &self.target,
+                &mut control_flow,
+                &mut callback,
+            );
+
             // Process all pending events
             self.drain_events(&mut callback, &mut control_flow);
 
@@ -306,7 +328,7 @@ impl<T: 'static> EventLoop<T> {
             }
 
             let start = Instant::now();
-            let (mut cause, deadline, timeout);
+            let (deadline, timeout);
 
             match control_flow {
                 ControlFlow::Exit => break,
@@ -337,38 +359,20 @@ impl<T: 'static> EventLoop<T> {
                 }
             }
 
-            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();
-
-                callback(
-                    crate::event::Event::NewEvents(cause),
-                    &self.target,
-                    &mut control_flow,
-                );
-            } else {
+            // If the XConnection already contains buffered events, we don't
+            // need to wait for data on the socket.
+            if !self.event_processor.poll() {
                 self.poll.poll(&mut events, timeout).unwrap();
                 events.clear();
+            }
 
-                let wait_cancelled = deadline.map_or(false, |deadline| Instant::now() < deadline);
+            let wait_cancelled = deadline.map_or(false, |deadline| Instant::now() < deadline);
 
-                if wait_cancelled {
-                    cause = StartCause::WaitCancelled {
-                        start,
-                        requested_resume: deadline,
-                    };
-                }
-
-                callback(
-                    crate::event::Event::NewEvents(cause),
-                    &self.target,
-                    &mut control_flow,
-                );
+            if wait_cancelled {
+                cause = StartCause::WaitCancelled {
+                    start,
+                    requested_resume: deadline,
+                };
             }
         }
 

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/window.rs

@@ -136,23 +136,23 @@ impl UnownedWindow {
                 })
                 .unwrap_or_else(|| monitors.swap_remove(0))
         };
-        let dpi_factor = guessed_monitor.scale_factor();
+        let scale_factor = guessed_monitor.scale_factor();
 
-        info!("Guessed window scale 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::<u32>(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::<u32>(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>(dpi_factor))
+                .map(|size| size.to_physical::<u32>(scale_factor))
                 .or_else(|| Some((800, 600).into()))
                 .map(Into::into)
                 .unwrap();
@@ -324,10 +324,10 @@ impl UnownedWindow {
             {
                 let mut min_inner_size = window_attrs
                     .min_inner_size
-                    .map(|size| size.to_physical::<u32>(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::<u32>(dpi_factor));
+                    .map(|size| size.to_physical::<u32>(scale_factor));
 
                 if !window_attrs.resizable {
                     if util::wm_name_is_one_of(&["Xfwm4"]) {
@@ -351,12 +351,12 @@ impl UnownedWindow {
                 normal_hints.set_resize_increments(
                     pl_attribs
                         .resize_increments
-                        .map(|size| size.to_physical::<u32>(dpi_factor).into()),
+                        .map(|size| size.to_physical::<u32>(scale_factor).into()),
                 );
                 normal_hints.set_base_size(
                     pl_attribs
                         .base_size
-                        .map(|size| size.to_physical::<u32>(dpi_factor).into()),
+                        .map(|size| size.to_physical::<u32>(scale_factor).into()),
                 );
                 xconn.set_normal_hints(window.xwindow, normal_hints).queue();
             }
@@ -1053,8 +1053,8 @@ impl UnownedWindow {
 
     #[inline]
     pub fn set_inner_size(&self, size: Size) {
-        let dpi_factor = self.scale_factor();
-        let (width, height) = size.to_physical::<u32>(dpi_factor).into();
+        let scale_factor = self.scale_factor();
+        let (width, height) = size.to_physical::<u32>(scale_factor).into();
         self.set_inner_size_physical(width, height);
     }
 
@@ -1097,16 +1097,16 @@ impl UnownedWindow {
 
     pub(crate) fn adjust_for_dpi(
         &self,
-        old_dpi_factor: f64,
-        new_dpi_factor: f64,
+        old_scale_factor: f64,
+        new_scale_factor: f64,
         width: u32,
         height: u32,
         shared_state: &SharedState,
     ) -> (u32, u32) {
-        let scale_factor = new_dpi_factor / old_dpi_factor;
+        let scale_factor = new_scale_factor / old_scale_factor;
         self.update_normal_hints(|normal_hints| {
             let dpi_adjuster =
-                |size: Size| -> (u32, u32) { size.to_physical::<u32>(new_dpi_factor).into() };
+                |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);
@@ -1146,12 +1146,12 @@ impl UnownedWindow {
 
         self.set_maximizable_inner(resizable).queue();
 
-        let dpi_factor = self.scale_factor();
+        let scale_factor = self.scale_factor();
         let min_inner_size = min_size
-            .map(|size| size.to_physical::<u32>(dpi_factor))
+            .map(|size| size.to_physical::<u32>(scale_factor))
             .map(Into::into);
         let max_inner_size = max_size
-            .map(|size| size.to_physical::<u32>(dpi_factor))
+            .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);

src/platform_impl/macos/event_loop.rs

@@ -117,6 +117,14 @@ pub struct Proxy<T> {
 
 unsafe impl<T: Send> Send for Proxy<T> {}
 
+impl<T> Drop for Proxy<T> {
+    fn drop(&mut self) {
+        unsafe {
+            CFRelease(self.source as _);
+        }
+    }
+}
+
 impl<T> Clone for Proxy<T> {
     fn clone(&self) -> Self {
         Proxy::new(self.sender.clone())

src/platform_impl/macos/mod.rs

@@ -25,6 +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/view.rs

@@ -50,13 +50,13 @@ 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>,
 }
 
@@ -383,8 +383,13 @@ extern "C" fn reset_cursor_rects(this: &Object, _sel: Sel) {
     }
 }
 
-extern "C" fn has_marked_text(_this: &Object, _sel: Sel) -> BOOL {
-    YES
+extern "C" fn has_marked_text(this: &Object, _sel: Sel) -> BOOL {
+    unsafe {
+        trace!("Triggered `hasMarkedText`");
+        let marked_text: id = *this.get_ivar("markedText");
+        trace!("Completed `hasMarkedText`");
+        (marked_text.length() > 0) as i8
+    }
 }
 
 extern "C" fn marked_range(this: &Object, _sel: Sel) -> NSRange {
@@ -618,6 +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 {
@@ -633,6 +651,8 @@ 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,
@@ -686,6 +706,8 @@ 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)),
@@ -750,16 +772,18 @@ 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(EventWrapper::StaticEvent(Event::WindowEvent {
-                window_id: WindowId(get_window_id(state.ns_window)),
+                window_id,
                 event,
             }));
         }
 
-        AppState::queue_event(EventWrapper::StaticEvent(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`");
@@ -801,6 +825,8 @@ 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)),
@@ -826,6 +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 {
@@ -841,26 +869,32 @@ fn mouse_click(this: &Object, event: id, button: MouseButton, button_state: Elem
 }
 
 extern "C" fn mouse_down(this: &Object, _sel: Sel, event: id) {
+    mouse_motion(this, event);
     mouse_click(this, event, MouseButton::Left, ElementState::Pressed);
 }
 
 extern "C" fn mouse_up(this: &Object, _sel: Sel, event: id) {
+    mouse_motion(this, event);
     mouse_click(this, event, MouseButton::Left, ElementState::Released);
 }
 
 extern "C" fn right_mouse_down(this: &Object, _sel: Sel, event: id) {
+    mouse_motion(this, event);
     mouse_click(this, event, MouseButton::Right, ElementState::Pressed);
 }
 
 extern "C" fn right_mouse_up(this: &Object, _sel: Sel, event: id) {
+    mouse_motion(this, event);
     mouse_click(this, event, MouseButton::Right, ElementState::Released);
 }
 
 extern "C" fn other_mouse_down(this: &Object, _sel: Sel, event: id) {
+    mouse_motion(this, event);
     mouse_click(this, event, MouseButton::Middle, ElementState::Pressed);
 }
 
 extern "C" fn other_mouse_up(this: &Object, _sel: Sel, event: id) {
+    mouse_motion(this, event);
     mouse_click(this, event, MouseButton::Middle, ElementState::Released);
 }
 
@@ -889,6 +923,8 @@ fn mouse_motion(this: &Object, event: id) {
         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 {
@@ -918,7 +954,7 @@ 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");
@@ -932,7 +968,6 @@ extern "C" fn mouse_entered(this: &Object, _sel: Sel, event: id) {
         };
 
         AppState::queue_event(EventWrapper::StaticEvent(enter_event));
-        mouse_motion(this, event);
     }
     trace!("Completed `mouseEntered`");
 }
@@ -957,6 +992,9 @@ extern "C" fn mouse_exited(this: &Object, _sel: Sel, _event: id) {
 
 extern "C" fn scroll_wheel(this: &Object, _sel: Sel, event: id) {
     trace!("Triggered `scrollWheel`");
+
+    mouse_motion(this, event);
+
     unsafe {
         let delta = {
             let (x, y) = (event.scrollingDeltaX(), event.scrollingDeltaY());
@@ -982,6 +1020,8 @@ 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 {
@@ -1000,6 +1040,9 @@ extern "C" fn scroll_wheel(this: &Object, _sel: Sel, event: id) {
 
 extern "C" fn pressure_change_with_event(this: &Object, _sel: Sel, event: id) {
     trace!("Triggered `pressureChangeWithEvent`");
+
+    mouse_motion(this, event);
+
     unsafe {
         let state_ptr: *mut c_void = *this.get_ivar("winitState");
         let state = &mut *(state_ptr as *mut ViewState);

src/platform_impl/macos/window.rs

@@ -340,7 +340,7 @@ impl UnownedWindow {
 
         let input_context = unsafe { util::create_input_context(*ns_view) };
 
-        let dpi_factor = unsafe { NSWindow::backingScaleFactor(*ns_window) as f64 };
+        let scale_factor = unsafe { NSWindow::backingScaleFactor(*ns_window) as f64 };
 
         unsafe {
             if win_attribs.transparent {
@@ -350,11 +350,11 @@ impl UnownedWindow {
 
             ns_app.activateIgnoringOtherApps_(YES);
             win_attribs.min_inner_size.map(|dim| {
-                let logical_dim = dim.to_logical(dpi_factor);
+                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(dpi_factor);
+                let logical_dim = dim.to_logical(scale_factor);
                 set_max_inner_size(*ns_window, logical_dim)
             });
 
@@ -378,7 +378,7 @@ impl UnownedWindow {
         let decorations = win_attribs.decorations;
         let inner_rect = win_attribs
             .inner_size
-            .map(|size| size.to_physical(dpi_factor));
+            .map(|size| size.to_physical(scale_factor));
 
         let window = Arc::new(UnownedWindow {
             ns_view,
@@ -450,8 +450,8 @@ impl UnownedWindow {
             frame_rect.origin.x as f64,
             util::bottom_left_to_top_left(frame_rect),
         );
-        let dpi_factor = self.scale_factor();
-        Ok(position.to_physical(dpi_factor))
+        let scale_factor = self.scale_factor();
+        Ok(position.to_physical(scale_factor))
     }
 
     pub fn inner_position(&self) -> Result<PhysicalPosition<i32>, NotSupportedError> {
@@ -462,13 +462,13 @@ impl UnownedWindow {
             content_rect.origin.x as f64,
             util::bottom_left_to_top_left(content_rect),
         );
-        let dpi_factor = self.scale_factor();
-        Ok(position.to_physical(dpi_factor))
+        let scale_factor = self.scale_factor();
+        Ok(position.to_physical(scale_factor))
     }
 
     pub fn set_outer_position(&self, position: Position) {
-        let dpi_factor = self.scale_factor();
-        let position = position.to_logical(dpi_factor);
+        let scale_factor = self.scale_factor();
+        let position = position.to_logical(scale_factor);
         let dummy = NSRect::new(
             NSPoint::new(
                 position.x,
@@ -488,8 +488,8 @@ impl UnownedWindow {
         let view_frame = unsafe { NSView::frame(*self.ns_view) };
         let logical: LogicalSize<f64> =
             (view_frame.size.width as f64, view_frame.size.height as f64).into();
-        let dpi_factor = self.scale_factor();
-        logical.to_physical(dpi_factor)
+        let scale_factor = self.scale_factor();
+        logical.to_physical(scale_factor)
     }
 
     #[inline]
@@ -497,15 +497,15 @@ impl UnownedWindow {
         let view_frame = unsafe { NSWindow::frame(*self.ns_window) };
         let logical: LogicalSize<f64> =
             (view_frame.size.width as f64, view_frame.size.height as f64).into();
-        let dpi_factor = self.scale_factor();
-        logical.to_physical(dpi_factor)
+        let scale_factor = self.scale_factor();
+        logical.to_physical(scale_factor)
     }
 
     #[inline]
     pub fn set_inner_size(&self, size: Size) {
         unsafe {
-            let dpi_factor = self.scale_factor();
-            util::set_content_size_async(*self.ns_window, size.to_logical(dpi_factor));
+            let scale_factor = self.scale_factor();
+            util::set_content_size_async(*self.ns_window, size.to_logical(scale_factor));
         }
     }
 
@@ -515,8 +515,8 @@ impl UnownedWindow {
                 width: 0.0,
                 height: 0.0,
             }));
-            let dpi_factor = self.scale_factor();
-            set_min_inner_size(*self.ns_window, dimensions.to_logical(dpi_factor));
+            let scale_factor = self.scale_factor();
+            set_min_inner_size(*self.ns_window, dimensions.to_logical(scale_factor));
         }
     }
 
@@ -526,8 +526,8 @@ impl UnownedWindow {
                 width: std::f32::MAX as f64,
                 height: std::f32::MAX as f64,
             }));
-            let dpi_factor = self.scale_factor();
-            set_max_inner_size(*self.ns_window, dimensions.to_logical(dpi_factor));
+            let scale_factor = self.scale_factor();
+            set_max_inner_size(*self.ns_window, dimensions.to_logical(scale_factor));
         }
     }
 
@@ -594,9 +594,9 @@ impl UnownedWindow {
     #[inline]
     pub fn set_cursor_position(&self, cursor_position: Position) -> Result<(), ExternalError> {
         let physical_window_position = self.inner_position().unwrap();
-        let dpi_factor = self.scale_factor();
-        let window_position = physical_window_position.to_logical::<CGFloat>(dpi_factor);
-        let logical_cursor_position = cursor_position.to_logical::<CGFloat>(dpi_factor);
+        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: logical_cursor_position.x + window_position.x,
             y: logical_cursor_position.y + window_position.y,
@@ -933,8 +933,8 @@ impl UnownedWindow {
 
     #[inline]
     pub fn set_ime_position(&self, spot: Position) {
-        let dpi_factor = self.scale_factor();
-        let logical_spot = spot.to_logical(dpi_factor);
+        let scale_factor = self.scale_factor();
+        let logical_spot = spot.to_logical(scale_factor);
         unsafe {
             view::set_ime_position(
                 *self.ns_view,
@@ -1028,7 +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_());
 

src/platform_impl/macos/window_delegate.rs

@@ -16,11 +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},
@@ -43,7 +44,7 @@ pub struct WindowDelegateState {
     previous_position: Option<(f64, f64)>,
 
     // Used to prevent redundant events.
-    previous_dpi_factor: f64,
+    previous_scale_factor: f64,
 }
 
 impl WindowDelegateState {
@@ -55,7 +56,7 @@ impl WindowDelegateState {
             window: Arc::downgrade(&window),
             initial_fullscreen,
             previous_position: None,
-            previous_dpi_factor: scale_factor,
+            previous_scale_factor: scale_factor,
         };
 
         if scale_factor != 1.0 {
@@ -82,11 +83,11 @@ impl WindowDelegateState {
 
     pub fn emit_static_scale_factor_changed_event(&mut self) {
         let scale_factor = self.get_scale_factor();
-        if scale_factor == self.previous_dpi_factor {
+        if scale_factor == self.previous_scale_factor {
             return ();
         };
 
-        self.previous_dpi_factor = scale_factor;
+        self.previous_scale_factor = scale_factor;
         let wrapper = EventWrapper::EventProxy(EventProxy::DpiChangedProxy {
             ns_window: IdRef::retain(*self.ns_window),
             suggested_size: self.view_size(),
@@ -319,6 +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/runner.rs

@@ -202,7 +202,6 @@ impl<T: 'static> Shared<T> {
     // It should only ever be called from send_event
     fn handle_event(&self, event: Event<'static, T>, control: &mut root::ControlFlow) {
         let is_closed = self.is_closed();
-
         match *self.0.runner.borrow_mut() {
             Some(ref mut runner) => {
                 // An event is being processed, so the runner should be marked busy
@@ -227,7 +226,9 @@ impl<T: 'static> Shared<T> {
         // If the runner doesn't exist and this method recurses, it will recurse infinitely
         if !is_closed && self.0.runner.borrow().is_some() {
             // Take an event out of the queue and handle it
-            if let Some(event) = self.0.events.borrow_mut().pop_front() {
+            // Make sure not to let the borrow_mut live during the next handle_event
+            let event = { self.0.events.borrow_mut().pop_front() };
+            if let Some(event) = event {
                 self.handle_event(event, control);
             }
         }
@@ -240,7 +241,7 @@ impl<T: 'static> Shared<T> {
             root::ControlFlow::Poll => {
                 let cloned = self.clone();
                 State::Poll {
-                    timeout: backend::Timeout::new(move || cloned.poll(), Duration::from_millis(0)),
+                    request: backend::AnimationFrameRequest::new(move || cloned.poll()),
                 }
             }
             root::ControlFlow::Wait => State::Wait {

src/platform_impl/web/event_loop/state.rs

@@ -15,7 +15,7 @@ pub enum State {
         start: Instant,
     },
     Poll {
-        timeout: backend::Timeout,
+        request: backend::AnimationFrameRequest,
     },
     Exit,
 }

src/platform_impl/web/event_loop/window_target.rs

@@ -2,7 +2,7 @@ use super::{backend, device, proxy::Proxy, runner, window};
 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> {
@@ -199,5 +199,18 @@ impl<T> WindowTarget<T> {
             });
             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

@@ -44,3 +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/stdweb/canvas.rs

@@ -6,6 +6,7 @@ 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::{
@@ -240,6 +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/mod.rs

@@ -3,13 +3,14 @@ mod event;
 mod timeout;
 
 pub use self::canvas::Canvas;
-pub use self::timeout::Timeout;
+pub use self::timeout::{AnimationFrameRequest, Timeout};
 
 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;
@@ -31,6 +32,15 @@ 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<f64> {

src/platform_impl/web/stdweb/timeout.rs

@@ -1,5 +1,7 @@
+use std::cell::Cell;
+use std::rc::Rc;
 use std::time::Duration;
-use stdweb::web::{window, IWindowOrWorker, TimeoutHandle};
+use stdweb::web::{window, IWindowOrWorker, RequestAnimationFrameHandle, TimeoutHandle};
 
 #[derive(Debug)]
 pub struct Timeout {
@@ -23,3 +25,39 @@ impl Drop for Timeout {
         handle.clear();
     }
 }
+
+#[derive(Debug)]
+pub struct AnimationFrameRequest {
+    handle: Option<RequestAnimationFrameHandle>,
+    // track callback state, because `cancelAnimationFrame` is slow
+    fired: Rc<Cell<bool>>,
+}
+
+impl AnimationFrameRequest {
+    pub fn new<F>(mut f: F) -> AnimationFrameRequest
+    where
+        F: 'static + FnMut(),
+    {
+        let fired = Rc::new(Cell::new(false));
+        let c_fired = fired.clone();
+        let handle = window().request_animation_frame(move |_| {
+            (*c_fired).set(true);
+            f();
+        });
+
+        AnimationFrameRequest {
+            handle: Some(handle),
+            fired,
+        }
+    }
+}
+
+impl Drop for AnimationFrameRequest {
+    fn drop(&mut self) {
+        if !(*self.fired).get() {
+            if let Some(handle) = self.handle.take() {
+                handle.cancel();
+            }
+        }
+    }
+}

src/platform_impl/web/web_sys/canvas.rs

@@ -8,7 +8,10 @@ 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.
@@ -26,6 +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 {
@@ -77,6 +81,7 @@ impl Canvas {
             on_mouse_wheel: None,
             on_fullscreen_change: None,
             wants_fullscreen: Rc::new(RefCell::new(false)),
+            on_dark_mode: None,
         })
     }
 
@@ -251,6 +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/mod.rs

@@ -3,7 +3,7 @@ mod event;
 mod timeout;
 
 pub use self::canvas::Canvas;
-pub use self::timeout::Timeout;
+pub use self::timeout::{AnimationFrameRequest, Timeout};
 
 use crate::dpi::{LogicalSize, Size};
 use crate::platform::web::WindowExtWebSys;
@@ -38,6 +38,17 @@ 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<f64> {

src/platform_impl/web/web_sys/timeout.rs

@@ -1,3 +1,5 @@
+use std::cell::Cell;
+use std::rc::Rc;
 use std::time::Duration;
 use wasm_bindgen::closure::Closure;
 use wasm_bindgen::JsCast;
@@ -38,3 +40,48 @@ impl Drop for Timeout {
         window.clear_timeout_with_handle(self.handle);
     }
 }
+
+#[derive(Debug)]
+pub struct AnimationFrameRequest {
+    handle: i32,
+    // track callback state, because `cancelAnimationFrame` is slow
+    fired: Rc<Cell<bool>>,
+    _closure: Closure<dyn FnMut()>,
+}
+
+impl AnimationFrameRequest {
+    pub fn new<F>(mut f: F) -> AnimationFrameRequest
+    where
+        F: 'static + FnMut(),
+    {
+        let window = web_sys::window().expect("Failed to obtain window");
+
+        let fired = Rc::new(Cell::new(false));
+        let c_fired = fired.clone();
+        let closure = Closure::wrap(Box::new(move || {
+            (*c_fired).set(true);
+            f();
+        }) as Box<dyn FnMut()>);
+
+        let handle = window
+            .request_animation_frame(&closure.as_ref().unchecked_ref())
+            .expect("Failed to request animation frame");
+
+        AnimationFrameRequest {
+            handle,
+            fired,
+            _closure: closure,
+        }
+    }
+}
+
+impl Drop for AnimationFrameRequest {
+    fn drop(&mut self) {
+        if !(*self.fired).get() {
+            let window = web_sys::window().expect("Failed to obtain window");
+            window
+                .cancel_animation_frame(self.handle)
+                .expect("Failed to cancel animation frame");
+        }
+    }
+}

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> {

src/platform_impl/windows/event_loop/runner.rs

@@ -1,51 +1,376 @@
-use std::{any::Any, cell::RefCell, collections::VecDeque, mem, panic, ptr, rc::Rc, time::Instant};
+use std::{
+    any::Any,
+    cell::{Cell, RefCell},
+    collections::{HashSet, VecDeque},
+    mem, panic, ptr,
+    rc::Rc,
+    time::Instant,
+};
 
-use winapi::{shared::windef::HWND, um::winuser};
+use winapi::{
+    shared::{minwindef::DWORD, windef::HWND},
+    um::winuser,
+};
 
 use crate::{
     dpi::PhysicalSize,
     event::{Event, StartCause, WindowEvent},
     event_loop::ControlFlow,
-    platform_impl::platform::{event_loop::EventLoop, util},
+    platform_impl::platform::util,
     window::WindowId,
 };
 
-pub(crate) type EventLoopRunnerShared<T> = Rc<ELRShared<T>>;
-pub(crate) struct ELRShared<T: 'static> {
-    runner: RefCell<Option<EventLoopRunner<T>>>,
-    buffer: RefCell<VecDeque<BufferedEvent<T>>>,
-    redraw_buffer: Rc<RefCell<VecDeque<WindowId>>>,
-}
-struct EventLoopRunner<T: 'static> {
-    control_flow: ControlFlow,
-    runner_state: RunnerState,
-    modal_redraw_window: HWND,
-    in_modal_loop: bool,
-    event_handler: Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>,
-    panic_error: Option<PanicError>,
-    redraw_buffer: Rc<RefCell<VecDeque<WindowId>>>,
+pub(crate) type EventLoopRunnerShared<T> = Rc<EventLoopRunner<T>>;
+pub(crate) struct EventLoopRunner<T: 'static> {
+    // The event loop's win32 handles
+    thread_msg_target: HWND,
+    wait_thread_id: DWORD,
+
+    control_flow: Cell<ControlFlow>,
+    runner_state: Cell<RunnerState>,
+    last_events_cleared: Cell<Instant>,
+
+    event_handler: Cell<Option<Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>>>,
+    event_buffer: RefCell<VecDeque<BufferedEvent<T>>>,
+
+    owned_windows: Cell<HashSet<HWND>>,
+
+    panic_error: Cell<Option<PanicError>>,
 }
+
 pub type PanicError = Box<dyn Any + Send + 'static>;
 
-pub enum BufferedEvent<T: 'static> {
+/// See `move_state_to` function for details on how the state loop works.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+enum RunnerState {
+    /// The event loop has just been created, and an `Init` event must be sent.
+    Uninitialized,
+    /// The event loop is idling.
+    Idle,
+    /// The event loop is handling the OS's events and sending them to the user's callback.
+    /// `NewEvents` has been sent, and `MainEventsCleared` hasn't.
+    HandlingMainEvents,
+    /// The event loop is handling the redraw events and sending them to the user's callback.
+    /// `MainEventsCleared` has been sent, and `RedrawEventsCleared` hasn't.
+    HandlingRedrawEvents,
+}
+
+enum BufferedEvent<T: 'static> {
     Event(Event<'static, T>),
     ScaleFactorChanged(WindowId, f64, PhysicalSize<u32>),
 }
 
-#[must_use]
-#[derive(Debug, Clone, Copy)]
-pub enum AreEventsBuffered {
-    EventsBuffered,
-    ReadyToSleep,
+impl<T> EventLoopRunner<T> {
+    pub(crate) fn new(thread_msg_target: HWND, wait_thread_id: DWORD) -> EventLoopRunner<T> {
+        EventLoopRunner {
+            thread_msg_target,
+            wait_thread_id,
+            runner_state: Cell::new(RunnerState::Uninitialized),
+            control_flow: Cell::new(ControlFlow::Poll),
+            panic_error: Cell::new(None),
+            last_events_cleared: Cell::new(Instant::now()),
+            event_handler: Cell::new(None),
+            event_buffer: RefCell::new(VecDeque::new()),
+            owned_windows: Cell::new(HashSet::new()),
+        }
+    }
+
+    pub(crate) unsafe fn set_event_handler<F>(&self, f: F)
+    where
+        F: FnMut(Event<'_, T>, &mut ControlFlow),
+    {
+        let old_event_handler = self.event_handler.replace(mem::transmute::<
+            Option<Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>>,
+            Option<Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>>,
+        >(Some(Box::new(f))));
+        assert!(old_event_handler.is_none());
+    }
+
+    pub(crate) fn reset_runner(&self) {
+        let EventLoopRunner {
+            thread_msg_target: _,
+            wait_thread_id: _,
+            runner_state,
+            panic_error,
+            control_flow,
+            last_events_cleared: _,
+            event_handler,
+            event_buffer: _,
+            owned_windows: _,
+        } = self;
+        runner_state.set(RunnerState::Uninitialized);
+        panic_error.set(None);
+        control_flow.set(ControlFlow::Poll);
+        event_handler.set(None);
+    }
 }
 
-impl AreEventsBuffered {
-    pub fn events_buffered(&self) -> bool {
-        match self {
-            Self::EventsBuffered => true,
-            Self::ReadyToSleep => false,
+/// State retrieval functions.
+impl<T> EventLoopRunner<T> {
+    pub fn thread_msg_target(&self) -> HWND {
+        self.thread_msg_target
+    }
+
+    pub fn wait_thread_id(&self) -> DWORD {
+        self.wait_thread_id
+    }
+
+    pub fn redrawing(&self) -> bool {
+        self.runner_state.get() == RunnerState::HandlingRedrawEvents
+    }
+
+    pub fn take_panic_error(&self) -> Result<(), PanicError> {
+        match self.panic_error.take() {
+            Some(err) => Err(err),
+            None => Ok(()),
         }
     }
+
+    pub fn control_flow(&self) -> ControlFlow {
+        self.control_flow.get()
+    }
+
+    pub fn handling_events(&self) -> bool {
+        self.runner_state.get() != RunnerState::Idle
+    }
+
+    pub fn should_buffer(&self) -> bool {
+        let handler = self.event_handler.take();
+        let should_buffer = handler.is_none();
+        self.event_handler.set(handler);
+        should_buffer
+    }
+}
+
+/// Misc. functions
+impl<T> EventLoopRunner<T> {
+    pub fn catch_unwind<R>(&self, f: impl FnOnce() -> R) -> Option<R> {
+        let panic_error = self.panic_error.take();
+        if panic_error.is_none() {
+            let result = panic::catch_unwind(panic::AssertUnwindSafe(f));
+
+            // Check to see if the panic error was set in a re-entrant call to catch_unwind inside
+            // of `f`. If it was, that error takes priority. If it wasn't, check if our call to
+            // catch_unwind caught any panics and set panic_error appropriately.
+            match self.panic_error.take() {
+                None => match result {
+                    Ok(r) => Some(r),
+                    Err(e) => {
+                        self.panic_error.set(Some(e));
+                        None
+                    }
+                },
+                Some(e) => {
+                    self.panic_error.set(Some(e));
+                    None
+                }
+            }
+        } else {
+            self.panic_error.set(panic_error);
+            None
+        }
+    }
+    pub fn register_window(&self, window: HWND) {
+        let mut owned_windows = self.owned_windows.take();
+        owned_windows.insert(window);
+        self.owned_windows.set(owned_windows);
+    }
+
+    pub fn remove_window(&self, window: HWND) {
+        let mut owned_windows = self.owned_windows.take();
+        owned_windows.remove(&window);
+        self.owned_windows.set(owned_windows);
+    }
+
+    pub fn owned_windows(&self, mut f: impl FnMut(HWND)) {
+        let mut owned_windows = self.owned_windows.take();
+        for hwnd in &owned_windows {
+            f(*hwnd);
+        }
+        let new_owned_windows = self.owned_windows.take();
+        owned_windows.extend(&new_owned_windows);
+        self.owned_windows.set(owned_windows);
+    }
+}
+
+/// Event dispatch functions.
+impl<T> EventLoopRunner<T> {
+    pub(crate) unsafe fn poll(&self) {
+        self.move_state_to(RunnerState::HandlingMainEvents);
+    }
+
+    pub(crate) unsafe fn send_event(&self, event: Event<'_, T>) {
+        if let Event::RedrawRequested(_) = event {
+            if self.runner_state.get() != RunnerState::HandlingRedrawEvents {
+                warn!("RedrawRequested dispatched without explicit MainEventsCleared");
+                self.move_state_to(RunnerState::HandlingRedrawEvents);
+            }
+            self.call_event_handler(event);
+        } else {
+            if self.should_buffer() {
+                // If the runner is already borrowed, we're in the middle of an event loop invocation. Add
+                // the event to a buffer to be processed later.
+                self.event_buffer
+                    .borrow_mut()
+                    .push_back(BufferedEvent::from_event(event))
+            } else {
+                self.move_state_to(RunnerState::HandlingMainEvents);
+                self.call_event_handler(event);
+                self.dispatch_buffered_events();
+            }
+        }
+    }
+
+    pub(crate) unsafe fn main_events_cleared(&self) {
+        self.move_state_to(RunnerState::HandlingRedrawEvents);
+    }
+
+    pub(crate) unsafe fn redraw_events_cleared(&self) {
+        self.move_state_to(RunnerState::Idle);
+    }
+
+    pub(crate) unsafe fn call_event_handler(&self, event: Event<'_, T>) {
+        self.catch_unwind(|| {
+            let mut control_flow = self.control_flow.take();
+            let mut event_handler = self.event_handler.take()
+                .expect("either event handler is re-entrant (likely), or no event handler is registered (very unlikely)");
+
+            if control_flow != ControlFlow::Exit {
+                event_handler(event, &mut control_flow);
+            } else {
+                event_handler(event, &mut ControlFlow::Exit);
+            }
+
+            assert!(self.event_handler.replace(Some(event_handler)).is_none());
+            self.control_flow.set(control_flow);
+        });
+    }
+
+    unsafe fn dispatch_buffered_events(&self) {
+        loop {
+            // We do this instead of using a `while let` loop because if we use a `while let`
+            // loop the reference returned `borrow_mut()` doesn't get dropped until the end
+            // of the loop's body and attempts to add events to the event buffer while in
+            // `process_event` will fail.
+            let buffered_event_opt = self.event_buffer.borrow_mut().pop_front();
+            match buffered_event_opt {
+                Some(e) => e.dispatch_event(|e| self.call_event_handler(e)),
+                None => break,
+            }
+        }
+    }
+
+    /// Dispatch control flow events (`NewEvents`, `MainEventsCleared`, and `RedrawEventsCleared`) as
+    /// necessary to bring the internal `RunnerState` to the new runner state.
+    ///
+    /// The state transitions are defined as follows:
+    ///
+    /// ```text
+    ///    Uninitialized
+    ///          |
+    ///          V
+    ///  HandlingMainEvents
+    ///   ^            |
+    ///   |            V
+    /// Idle <--- HandlingRedrawEvents
+    /// ```
+    ///
+    /// Attempting to transition back to `Uninitialized` will result in a panic. Transitioning to
+    /// the current state is a no-op. Even if the `new_runner_state` isn't the immediate next state
+    /// in the runner state machine (e.g. `self.runner_state == HandlingMainEvents` and
+    /// `new_runner_state == Idle`), the intermediate state transitions will still be executed.
+    unsafe fn move_state_to(&self, new_runner_state: RunnerState) {
+        use RunnerState::{HandlingMainEvents, HandlingRedrawEvents, Idle, Uninitialized};
+
+        match (
+            self.runner_state.replace(new_runner_state),
+            new_runner_state,
+        ) {
+            (Uninitialized, Uninitialized)
+            | (Idle, Idle)
+            | (HandlingMainEvents, HandlingMainEvents)
+            | (HandlingRedrawEvents, HandlingRedrawEvents) => (),
+
+            // State transitions that initialize the event loop.
+            (Uninitialized, HandlingMainEvents) => {
+                self.call_new_events(true);
+            }
+            (Uninitialized, HandlingRedrawEvents) => {
+                self.call_new_events(true);
+                self.call_event_handler(Event::MainEventsCleared);
+            }
+            (Uninitialized, Idle) => {
+                self.call_new_events(true);
+                self.call_event_handler(Event::MainEventsCleared);
+                self.call_redraw_events_cleared();
+            }
+            (_, Uninitialized) => panic!("cannot move state to Uninitialized"),
+
+            // State transitions that start the event handling process.
+            (Idle, HandlingMainEvents) => {
+                self.call_new_events(false);
+            }
+            (Idle, HandlingRedrawEvents) => {
+                self.call_new_events(false);
+                self.call_event_handler(Event::MainEventsCleared);
+            }
+
+            (HandlingMainEvents, HandlingRedrawEvents) => {
+                self.call_event_handler(Event::MainEventsCleared);
+            }
+            (HandlingMainEvents, Idle) => {
+                warn!("RedrawEventsCleared emitted without explicit MainEventsCleared");
+                self.call_event_handler(Event::MainEventsCleared);
+                self.call_redraw_events_cleared();
+            }
+
+            (HandlingRedrawEvents, Idle) => {
+                self.call_redraw_events_cleared();
+            }
+            (HandlingRedrawEvents, HandlingMainEvents) => {
+                warn!("NewEvents emitted without explicit RedrawEventsCleared");
+                self.call_redraw_events_cleared();
+                self.call_new_events(false);
+            }
+        }
+    }
+
+    unsafe fn call_new_events(&self, init: bool) {
+        let start_cause = match (init, self.control_flow()) {
+            (true, _) => StartCause::Init,
+            (false, ControlFlow::Poll) => StartCause::Poll,
+            (false, ControlFlow::Exit) | (false, ControlFlow::Wait) => StartCause::WaitCancelled {
+                requested_resume: None,
+                start: self.last_events_cleared.get(),
+            },
+            (false, ControlFlow::WaitUntil(requested_resume)) => {
+                if Instant::now() < requested_resume {
+                    StartCause::WaitCancelled {
+                        requested_resume: Some(requested_resume),
+                        start: self.last_events_cleared.get(),
+                    }
+                } else {
+                    StartCause::ResumeTimeReached {
+                        requested_resume,
+                        start: self.last_events_cleared.get(),
+                    }
+                }
+            }
+        };
+        self.call_event_handler(Event::NewEvents(start_cause));
+        self.dispatch_buffered_events();
+        winuser::RedrawWindow(
+            self.thread_msg_target,
+            ptr::null(),
+            ptr::null_mut(),
+            winuser::RDW_INTERNALPAINT,
+        );
+    }
+
+    unsafe fn call_redraw_events_cleared(&self) {
+        self.call_event_handler(Event::RedrawEventsCleared);
+        self.last_events_cleared.set(Instant::now());
+    }
 }
 
 impl<T> BufferedEvent<T> {
@@ -83,489 +408,3 @@ impl<T> BufferedEvent<T> {
         }
     }
 }
-
-impl<T> ELRShared<T> {
-    pub(crate) fn new() -> ELRShared<T> {
-        ELRShared {
-            runner: RefCell::new(None),
-            buffer: RefCell::new(VecDeque::new()),
-            redraw_buffer: Default::default(),
-        }
-    }
-
-    pub(crate) unsafe fn set_runner<F>(&self, event_loop: &EventLoop<T>, f: F)
-    where
-        F: FnMut(Event<'_, T>, &mut ControlFlow),
-    {
-        let mut runner = EventLoopRunner::new(event_loop, self.redraw_buffer.clone(), f);
-        {
-            let mut runner_ref = self.runner.borrow_mut();
-            loop {
-                let event = self.buffer.borrow_mut().pop_front();
-                match event {
-                    Some(e) => e.dispatch_event(|e| runner.process_event(e)),
-                    None => break,
-                }
-            }
-            *runner_ref = Some(runner);
-        }
-    }
-
-    pub(crate) fn destroy_runner(&self) {
-        *self.runner.borrow_mut() = None;
-    }
-
-    pub(crate) fn new_events(&self) {
-        let mut runner_ref = self.runner.borrow_mut();
-        if let Some(ref mut runner) = *runner_ref {
-            runner.new_events();
-            loop {
-                let buffered_event_opt = self.buffer.borrow_mut().pop_front();
-                match buffered_event_opt {
-                    Some(e) => e.dispatch_event(|e| runner.process_event(e)),
-                    None => break,
-                }
-            }
-        }
-    }
-
-    pub(crate) unsafe fn send_event(&self, event: Event<'_, T>) {
-        let handling_redraw = self
-            .runner
-            .borrow()
-            .as_ref()
-            .map(|r| RunnerState::HandlingRedraw == r.runner_state)
-            .unwrap_or(false);
-        let mut send = None;
-        if handling_redraw {
-            if let Event::RedrawRequested(_) = event {
-                send = Some(event);
-            } else {
-                self.buffer_event(event);
-            }
-        } else {
-            send = Some(event);
-        }
-        if let Some(event) = send {
-            if let Err(event) = self.send_event_unbuffered(event) {
-                // If the runner is already borrowed, we're in the middle of an event loop invocation. Add
-                // the event to a buffer to be processed later.
-                self.buffer_event(event);
-            }
-        }
-    }
-
-    unsafe fn send_event_unbuffered<'e>(&self, event: Event<'e, T>) -> Result<(), Event<'e, T>> {
-        if let Ok(mut runner_ref) = self.runner.try_borrow_mut() {
-            if let Some(ref mut runner) = *runner_ref {
-                runner.process_event(event);
-
-                let handling_redraw = if let RunnerState::HandlingRedraw = runner.runner_state {
-                    true
-                } else {
-                    false
-                };
-
-                if !handling_redraw {
-                    // Dispatch any events that were buffered during the call to `process_event`.
-                    loop {
-                        // We do this instead of using a `while let` loop because if we use a `while let`
-                        // loop the reference returned `borrow_mut()` doesn't get dropped until the end
-                        // of the loop's body and attempts to add events to the event buffer while in
-                        // `process_event` will fail.
-                        let buffered_event_opt = self.buffer.borrow_mut().pop_front();
-                        match buffered_event_opt {
-                            Some(e) => e.dispatch_event(|e| runner.process_event(e)),
-                            None => break,
-                        }
-                    }
-                }
-
-                return Ok(());
-            }
-        }
-
-        Err(event)
-    }
-
-    pub(crate) unsafe fn call_event_handler(&self, event: Event<'static, T>) {
-        if let Ok(mut runner_ref) = self.runner.try_borrow_mut() {
-            if let Some(ref mut runner) = *runner_ref {
-                runner.call_event_handler(event);
-                return;
-            }
-        }
-    }
-
-    pub(crate) fn main_events_cleared(&self) {
-        let mut runner_ref = self.runner.borrow_mut();
-        if let Some(ref mut runner) = *runner_ref {
-            runner.main_events_cleared();
-        }
-    }
-
-    pub(crate) fn redraw_events_cleared(&self) -> AreEventsBuffered {
-        let mut runner_ref = self.runner.borrow_mut();
-        if let Some(ref mut runner) = *runner_ref {
-            runner.redraw_events_cleared();
-        }
-        match self.buffer.borrow().len() {
-            0 => AreEventsBuffered::ReadyToSleep,
-            _ => AreEventsBuffered::EventsBuffered,
-        }
-    }
-
-    pub(crate) fn take_panic_error(&self) -> Result<(), PanicError> {
-        let mut runner_ref = self.runner.borrow_mut();
-        if let Some(ref mut runner) = *runner_ref {
-            runner.take_panic_error()
-        } else {
-            Ok(())
-        }
-    }
-
-    pub(crate) fn set_modal_loop(&self, in_modal_loop: bool) {
-        let mut runner_ref = self.runner.borrow_mut();
-        if let Some(ref mut runner) = *runner_ref {
-            runner.in_modal_loop = in_modal_loop;
-        }
-    }
-
-    pub(crate) fn in_modal_loop(&self) -> bool {
-        let runner = self.runner.borrow();
-        if let Some(ref runner) = *runner {
-            runner.in_modal_loop
-        } else {
-            false
-        }
-    }
-
-    pub fn control_flow(&self) -> ControlFlow {
-        let runner_ref = self.runner.borrow();
-        if let Some(ref runner) = *runner_ref {
-            runner.control_flow
-        } else {
-            ControlFlow::Exit
-        }
-    }
-
-    fn buffer_event(&self, event: Event<'_, T>) {
-        match event {
-            Event::RedrawRequested(window_id) => {
-                self.redraw_buffer.borrow_mut().push_back(window_id)
-            }
-            _ => self
-                .buffer
-                .borrow_mut()
-                .push_back(BufferedEvent::from_event(event)),
-        }
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-enum RunnerState {
-    /// The event loop has just been created, and an `Init` event must be sent.
-    New,
-    /// The event loop is idling, and began idling at the given instant.
-    Idle(Instant),
-    /// The event loop has received a signal from the OS that the loop may resume, but no winit
-    /// events have been generated yet. We're waiting for an event to be processed or the events
-    /// to be marked as cleared to send `NewEvents`, depending on the current `ControlFlow`.
-    DeferredNewEvents(Instant),
-    /// The event loop is handling the OS's events and sending them to the user's callback.
-    /// `NewEvents` has been sent, and `MainEventsCleared` hasn't.
-    HandlingEvents,
-    HandlingRedraw,
-}
-
-impl<T> EventLoopRunner<T> {
-    unsafe fn new<F>(
-        event_loop: &EventLoop<T>,
-        redraw_buffer: Rc<RefCell<VecDeque<WindowId>>>,
-        f: F,
-    ) -> EventLoopRunner<T>
-    where
-        F: FnMut(Event<'_, T>, &mut ControlFlow),
-    {
-        EventLoopRunner {
-            control_flow: ControlFlow::default(),
-            runner_state: RunnerState::New,
-            in_modal_loop: false,
-            modal_redraw_window: event_loop.window_target.p.thread_msg_target,
-            event_handler: mem::transmute::<
-                Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>,
-                Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>,
-            >(Box::new(f)),
-            panic_error: None,
-            redraw_buffer,
-        }
-    }
-
-    fn take_panic_error(&mut self) -> Result<(), PanicError> {
-        match self.panic_error.take() {
-            Some(err) => Err(err),
-            None => Ok(()),
-        }
-    }
-
-    fn new_events(&mut self) {
-        self.runner_state = match self.runner_state {
-            // If we're already handling events or have deferred `NewEvents`, we don't need to do
-            // do any processing.
-            RunnerState::HandlingEvents
-            | RunnerState::HandlingRedraw
-            | RunnerState::DeferredNewEvents(..) => self.runner_state,
-
-            // Send the `Init` `NewEvents` and immediately move into event processing.
-            RunnerState::New => {
-                self.call_event_handler(Event::NewEvents(StartCause::Init));
-                RunnerState::HandlingEvents
-            }
-
-            // When `NewEvents` gets sent after an idle depends on the control flow...
-            RunnerState::Idle(wait_start) => {
-                match self.control_flow {
-                    // If we're polling, send `NewEvents` and immediately move into event processing.
-                    ControlFlow::Poll => {
-                        self.call_event_handler(Event::NewEvents(StartCause::Poll));
-                        RunnerState::HandlingEvents
-                    },
-                    // If the user was waiting until a specific time, the `NewEvents` call gets sent
-                    // at varying times depending on the current time.
-                    ControlFlow::WaitUntil(resume_time) => {
-                        match Instant::now() >= resume_time {
-                            // If the current time is later than the requested resume time, we can tell the
-                            // user that the resume time has been reached with `NewEvents` and immdiately move
-                            // into event processing.
-                            true => {
-                                self.call_event_handler(Event::NewEvents(StartCause::ResumeTimeReached {
-                                    start: wait_start,
-                                    requested_resume: resume_time,
-                                }));
-                                RunnerState::HandlingEvents
-                            },
-                            // However, if the current time is EARLIER than the requested resume time, we
-                            // don't want to send the `WaitCancelled` event until we know an event is being
-                            // sent. Defer.
-                            false => RunnerState::DeferredNewEvents(wait_start)
-                        }
-                    },
-                    // If we're waiting, `NewEvents` doesn't get sent until winit gets an event, so
-                    // we defer.
-                    ControlFlow::Wait |
-                    // `Exit` shouldn't really ever get sent here, but if it does do something somewhat sane.
-                    ControlFlow::Exit => RunnerState::DeferredNewEvents(wait_start),
-                }
-            }
-        };
-    }
-
-    fn process_event(&mut self, event: Event<'_, T>) {
-        // If we're in the modal loop, we need to have some mechanism for finding when the event
-        // queue has been cleared so we can call `events_cleared`. Windows doesn't give any utilities
-        // for doing this, but it DOES guarantee that WM_PAINT will only occur after input events have
-        // been processed. So, we send WM_PAINT to a dummy window which calls `events_cleared` when
-        // the events queue has been emptied.
-        if self.in_modal_loop {
-            unsafe {
-                winuser::RedrawWindow(
-                    self.modal_redraw_window,
-                    ptr::null(),
-                    ptr::null_mut(),
-                    winuser::RDW_INTERNALPAINT,
-                );
-            }
-        }
-
-        // If new event processing has to be done (i.e. call NewEvents or defer), do it. If we're
-        // already in processing nothing happens with this call.
-        self.new_events();
-
-        // Now that an event has been received, we have to send any `NewEvents` calls that were
-        // deferred.
-        if let RunnerState::DeferredNewEvents(wait_start) = self.runner_state {
-            match self.control_flow {
-                ControlFlow::Exit | ControlFlow::Wait => {
-                    self.call_event_handler(Event::NewEvents(StartCause::WaitCancelled {
-                        start: wait_start,
-                        requested_resume: None,
-                    }))
-                }
-                ControlFlow::WaitUntil(resume_time) => {
-                    let start_cause = match Instant::now() >= resume_time {
-                        // If the current time is later than the requested resume time, the resume time
-                        // has been reached.
-                        true => StartCause::ResumeTimeReached {
-                            start: wait_start,
-                            requested_resume: resume_time,
-                        },
-                        // Otherwise, the requested resume time HASN'T been reached and we send a WaitCancelled.
-                        false => StartCause::WaitCancelled {
-                            start: wait_start,
-                            requested_resume: Some(resume_time),
-                        },
-                    };
-                    self.call_event_handler(Event::NewEvents(start_cause));
-                }
-                // This can be reached if the control flow is changed to poll during a `RedrawRequested`
-                // that was sent after `MainEventsCleared`.
-                ControlFlow::Poll => self.call_event_handler(Event::NewEvents(StartCause::Poll)),
-            }
-        }
-
-        match (self.runner_state, &event) {
-            (RunnerState::HandlingRedraw, Event::RedrawRequested(_)) => {
-                self.call_event_handler(event)
-            }
-            (RunnerState::New, Event::RedrawRequested(_))
-            | (RunnerState::Idle(..), Event::RedrawRequested(_)) => {
-                self.new_events();
-                self.main_events_cleared();
-                self.call_event_handler(event);
-            }
-            (_, Event::RedrawRequested(_)) => {
-                panic!("redraw event in non-redraw phase");
-            }
-            (RunnerState::HandlingRedraw, _) => {
-                panic!(
-                    "Non-redraw event dispatched durning redraw phase: {:?}",
-                    event.map_nonuser_event::<()>().ok()
-                );
-            }
-            (_, _) => {
-                self.runner_state = RunnerState::HandlingEvents;
-                self.call_event_handler(event);
-            }
-        }
-    }
-
-    fn flush_redraws(&mut self) {
-        loop {
-            let redraw_window_opt = self.redraw_buffer.borrow_mut().pop_front();
-            match redraw_window_opt {
-                Some(window_id) => self.process_event(Event::RedrawRequested(window_id)),
-                None => break,
-            }
-        }
-    }
-
-    fn main_events_cleared(&mut self) {
-        match self.runner_state {
-            // If we were handling events, send the MainEventsCleared message.
-            RunnerState::HandlingEvents => {
-                self.call_event_handler(Event::MainEventsCleared);
-                self.runner_state = RunnerState::HandlingRedraw;
-            }
-
-            RunnerState::HandlingRedraw => (),
-
-            // If we *weren't* handling events, we don't have to do anything.
-            RunnerState::New | RunnerState::Idle(..) => (),
-
-            // Some control flows require a NewEvents call even if no events were received. This
-            // branch handles those.
-            RunnerState::DeferredNewEvents(wait_start) => {
-                match self.control_flow {
-                    // If we had deferred a Poll, send the Poll NewEvents and MainEventsCleared.
-                    ControlFlow::Poll => {
-                        self.call_event_handler(Event::NewEvents(StartCause::Poll));
-                        self.call_event_handler(Event::MainEventsCleared);
-                        self.runner_state = RunnerState::HandlingRedraw;
-                    }
-                    // If we had deferred a WaitUntil and the resume time has since been reached,
-                    // send the resume notification and MainEventsCleared event.
-                    ControlFlow::WaitUntil(resume_time) => {
-                        if Instant::now() >= resume_time {
-                            self.call_event_handler(Event::NewEvents(
-                                StartCause::ResumeTimeReached {
-                                    start: wait_start,
-                                    requested_resume: resume_time,
-                                },
-                            ));
-                            self.call_event_handler(Event::MainEventsCleared);
-                            self.runner_state = RunnerState::HandlingRedraw;
-                        }
-                    }
-                    // If we deferred a wait and no events were received, the user doesn't have to
-                    // get an event.
-                    ControlFlow::Wait | ControlFlow::Exit => (),
-                }
-            }
-        }
-    }
-
-    fn redraw_events_cleared(&mut self) {
-        match self.runner_state {
-            // If we were handling events, send the MainEventsCleared message.
-            RunnerState::HandlingEvents => {
-                self.call_event_handler(Event::MainEventsCleared);
-                self.runner_state = RunnerState::HandlingRedraw;
-                self.flush_redraws();
-                self.call_event_handler(Event::RedrawEventsCleared);
-                self.runner_state = RunnerState::Idle(Instant::now());
-            }
-
-            RunnerState::HandlingRedraw => {
-                self.flush_redraws();
-                self.call_event_handler(Event::RedrawEventsCleared);
-                self.runner_state = RunnerState::Idle(Instant::now());
-            }
-
-            // If we *weren't* handling events, we don't have to do anything.
-            RunnerState::New | RunnerState::Idle(..) => (),
-
-            // Some control flows require a NewEvents call even if no events were received. This
-            // branch handles those.
-            RunnerState::DeferredNewEvents(wait_start) => {
-                match self.control_flow {
-                    // If we had deferred a Poll, send the Poll NewEvents and MainEventsCleared.
-                    ControlFlow::Poll => {
-                        self.call_event_handler(Event::NewEvents(StartCause::Poll));
-                        self.call_event_handler(Event::MainEventsCleared);
-                        self.flush_redraws();
-                        self.call_event_handler(Event::RedrawEventsCleared);
-                    }
-                    // If we had deferred a WaitUntil and the resume time has since been reached,
-                    // send the resume notification and MainEventsCleared event.
-                    ControlFlow::WaitUntil(resume_time) => {
-                        if Instant::now() >= resume_time {
-                            self.call_event_handler(Event::NewEvents(
-                                StartCause::ResumeTimeReached {
-                                    start: wait_start,
-                                    requested_resume: resume_time,
-                                },
-                            ));
-                            self.call_event_handler(Event::MainEventsCleared);
-                            self.flush_redraws();
-                            self.call_event_handler(Event::RedrawEventsCleared);
-                        }
-                    }
-                    // If we deferred a wait and no events were received, the user doesn't have to
-                    // get an event.
-                    ControlFlow::Wait | ControlFlow::Exit => (),
-                }
-                // Mark that we've entered an idle state.
-                self.runner_state = RunnerState::Idle(wait_start)
-            }
-        }
-    }
-
-    fn call_event_handler(&mut self, event: Event<'_, T>) {
-        if self.panic_error.is_none() {
-            let EventLoopRunner {
-                ref mut panic_error,
-                ref mut event_handler,
-                ref mut control_flow,
-                ..
-            } = self;
-            *panic_error = panic::catch_unwind(panic::AssertUnwindSafe(|| {
-                if *control_flow != ControlFlow::Exit {
-                    (*event_handler)(event, control_flow);
-                } else {
-                    (*event_handler)(event, &mut ControlFlow::Exit);
-                }
-            }))
-            .err();
-        }
-    }
-}

src/platform_impl/windows/icon.rs

@@ -1,15 +1,17 @@
-use std::{io, mem, os::windows::ffi::OsStrExt, path::Path, ptr};
+use std::{fmt, io, iter::once, mem, os::windows::ffi::OsStrExt, path::Path, ptr, sync::Arc};
 
 use winapi::{
     ctypes::{c_int, wchar_t},
     shared::{
-        minwindef::{BYTE, LPARAM, WPARAM},
+        minwindef::{BYTE, LPARAM, WORD, WPARAM},
         windef::{HICON, HWND},
     },
+    um::libloaderapi,
     um::winuser,
 };
 
-use crate::icon::{Icon, Pixel, PIXEL_SIZE};
+use crate::dpi::PhysicalSize;
+use crate::icon::*;
 
 impl Pixel {
     fn to_bgra(&mut self) {
@@ -17,92 +19,149 @@ impl Pixel {
     }
 }
 
+impl RgbaIcon {
+    fn into_windows_icon(self) -> Result<WinIcon, BadIcon> {
+        let mut rgba = self.rgba;
+        let pixel_count = rgba.len() / PIXEL_SIZE;
+        let mut and_mask = Vec::with_capacity(pixel_count);
+        let pixels =
+            unsafe { std::slice::from_raw_parts_mut(rgba.as_mut_ptr() as *mut Pixel, pixel_count) };
+        for pixel in pixels {
+            and_mask.push(pixel.a.wrapping_sub(std::u8::MAX)); // invert alpha channel
+            pixel.to_bgra();
+        }
+        assert_eq!(and_mask.len(), pixel_count);
+        let handle = unsafe {
+            winuser::CreateIcon(
+                ptr::null_mut(),
+                self.width as c_int,
+                self.height as c_int,
+                1,
+                (PIXEL_SIZE * 8) as BYTE,
+                and_mask.as_ptr() as *const BYTE,
+                rgba.as_ptr() as *const BYTE,
+            ) as HICON
+        };
+        if !handle.is_null() {
+            Ok(WinIcon::from_handle(handle))
+        } else {
+            Err(BadIcon::OsError(io::Error::last_os_error()))
+        }
+    }
+}
+
 #[derive(Debug)]
 pub enum IconType {
     Small = winuser::ICON_SMALL as isize,
     Big = winuser::ICON_BIG as isize,
 }
 
-#[derive(Clone, Debug)]
+#[derive(Debug)]
+struct RaiiIcon {
+    handle: HICON,
+}
+
+#[derive(Clone)]
 pub struct WinIcon {
-    pub handle: HICON,
+    inner: Arc<RaiiIcon>,
 }
 
 unsafe impl Send for WinIcon {}
 
 impl WinIcon {
-    #[allow(dead_code)]
-    pub fn from_path<P: AsRef<Path>>(path: P) -> Result<Self, io::Error> {
-        let wide_path: Vec<u16> = path.as_ref().as_os_str().encode_wide().collect();
+    pub fn as_raw_handle(&self) -> HICON {
+        self.inner.handle
+    }
+
+    pub fn from_path<P: AsRef<Path>>(
+        path: P,
+        size: Option<PhysicalSize<u32>>,
+    ) -> Result<Self, BadIcon> {
+        let wide_path: Vec<u16> = path
+            .as_ref()
+            .as_os_str()
+            .encode_wide()
+            .chain(once(0))
+            .collect();
+
+        // width / height of 0 along with LR_DEFAULTSIZE tells windows to load the default icon size
+        let (width, height) = size.map(Into::into).unwrap_or((0, 0));
+
         let handle = unsafe {
             winuser::LoadImageW(
                 ptr::null_mut(),
                 wide_path.as_ptr() as *const wchar_t,
                 winuser::IMAGE_ICON,
-                0, // 0 indicates that we want to use the actual width
-                0, // and height
-                winuser::LR_LOADFROMFILE,
-            ) as HICON
-        };
-        if !handle.is_null() {
-            Ok(WinIcon { handle })
-        } else {
-            Err(io::Error::last_os_error())
-        }
-    }
-
-    pub fn from_icon(icon: Icon) -> Result<Self, io::Error> {
-        Self::from_rgba(icon.rgba, icon.width, icon.height)
-    }
-
-    pub fn from_rgba(mut rgba: Vec<u8>, width: u32, height: u32) -> Result<Self, io::Error> {
-        assert_eq!(rgba.len() % PIXEL_SIZE, 0);
-        let pixel_count = rgba.len() / PIXEL_SIZE;
-        assert_eq!(pixel_count, (width * height) as usize);
-        let mut and_mask = Vec::with_capacity(pixel_count);
-        let pixels = rgba.as_mut_ptr() as *mut Pixel; // how not to write idiomatic Rust
-        for pixel_index in 0..pixel_count {
-            let pixel = unsafe { &mut *pixels.offset(pixel_index as isize) };
-            and_mask.push(pixel.a.wrapping_sub(std::u8::MAX)); // invert alpha channel
-            pixel.to_bgra();
-        }
-        assert_eq!(and_mask.len(), pixel_count);
-        let handle = unsafe {
-            winuser::CreateIcon(
-                ptr::null_mut(),
                 width as c_int,
                 height as c_int,
-                1,
-                (PIXEL_SIZE * 8) as BYTE,
-                and_mask.as_ptr() as *const BYTE,
-                rgba.as_ptr() as *const BYTE,
+                winuser::LR_DEFAULTSIZE | winuser::LR_LOADFROMFILE,
             ) as HICON
         };
         if !handle.is_null() {
-            Ok(WinIcon { handle })
+            Ok(WinIcon::from_handle(handle))
         } else {
-            Err(io::Error::last_os_error())
+            Err(BadIcon::OsError(io::Error::last_os_error()))
         }
     }
 
+    pub fn from_resource(
+        resource_id: WORD,
+        size: Option<PhysicalSize<u32>>,
+    ) -> Result<Self, BadIcon> {
+        // width / height of 0 along with LR_DEFAULTSIZE tells windows to load the default icon size
+        let (width, height) = size.map(Into::into).unwrap_or((0, 0));
+        let handle = unsafe {
+            winuser::LoadImageW(
+                libloaderapi::GetModuleHandleW(ptr::null_mut()),
+                winuser::MAKEINTRESOURCEW(resource_id),
+                winuser::IMAGE_ICON,
+                width as c_int,
+                height as c_int,
+                winuser::LR_DEFAULTSIZE,
+            ) as HICON
+        };
+        if !handle.is_null() {
+            Ok(WinIcon::from_handle(handle))
+        } else {
+            Err(BadIcon::OsError(io::Error::last_os_error()))
+        }
+    }
+
+    pub fn from_rgba(rgba: Vec<u8>, width: u32, height: u32) -> Result<Self, BadIcon> {
+        let rgba_icon = RgbaIcon::from_rgba(rgba, width, height)?;
+        rgba_icon.into_windows_icon()
+    }
+
     pub fn set_for_window(&self, hwnd: HWND, icon_type: IconType) {
         unsafe {
             winuser::SendMessageW(
                 hwnd,
                 winuser::WM_SETICON,
                 icon_type as WPARAM,
-                self.handle as LPARAM,
+                self.as_raw_handle() as LPARAM,
             );
         }
     }
+
+    fn from_handle(handle: HICON) -> Self {
+        Self {
+            inner: Arc::new(RaiiIcon { handle }),
+        }
+    }
 }
 
-impl Drop for WinIcon {
+impl Drop for RaiiIcon {
     fn drop(&mut self) {
         unsafe { winuser::DestroyIcon(self.handle) };
     }
 }
 
+impl fmt::Debug for WinIcon {
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
+        (*self.inner).fmt(formatter)
+    }
+}
+
 pub fn unset_for_window(hwnd: HWND, icon_type: IconType) {
     unsafe {
         winuser::SendMessageW(hwnd, winuser::WM_SETICON, icon_type as WPARAM, 0 as LPARAM);

src/platform_impl/windows/mod.rs

@@ -4,11 +4,15 @@ use winapi::{self, shared::windef::HWND};
 
 pub use self::{
     event_loop::{EventLoop, EventLoopProxy, EventLoopWindowTarget},
+    icon::WinIcon,
     monitor::{MonitorHandle, VideoMode},
     window::Window,
 };
 
-use crate::{event::DeviceId as RootDeviceId, window::Icon};
+pub use self::icon::WinIcon as PlatformIcon;
+
+use crate::event::DeviceId as RootDeviceId;
+use crate::icon::Icon;
 
 #[derive(Clone, Default)]
 pub struct PlatformSpecificWindowBuilderAttributes {

src/platform_impl/windows/util.rs

@@ -116,7 +116,7 @@ pub(crate) fn set_inner_size_physical(window: HWND, x: u32, y: u32) {
                 | winuser::SWP_NOMOVE
                 | winuser::SWP_NOACTIVATE,
         );
-        winuser::UpdateWindow(window);
+        winuser::InvalidateRgn(window, ptr::null_mut(), 0);
     }
 }
 

src/platform_impl/windows/window.rs

@@ -32,18 +32,19 @@ use winapi::{
 use crate::{
     dpi::{PhysicalPosition, PhysicalSize, Position, Size},
     error::{ExternalError, NotSupportedError, OsError as RootOsError},
+    icon::Icon,
     monitor::MonitorHandle as RootMonitorHandle,
     platform_impl::platform::{
         dark_mode::try_dark_mode,
         dpi::{dpi_to_scale_factor, hwnd_dpi},
         drop_handler::FileDropHandler,
         event_loop::{self, EventLoopWindowTarget, DESTROY_MSG_ID},
-        icon::{self, IconType, WinIcon},
+        icon::{self, IconType},
         monitor, util,
         window_state::{CursorFlags, SavedWindow, WindowFlags, WindowState},
         PlatformSpecificWindowBuilderAttributes, WindowId,
     },
-    window::{CursorIcon, Fullscreen, Icon, WindowAttributes},
+    window::{CursorIcon, Fullscreen, WindowAttributes},
 };
 
 /// The Win32 implementation of the main `Window` object.
@@ -187,7 +188,7 @@ impl Window {
                     | winuser::SWP_NOSIZE
                     | winuser::SWP_NOACTIVATE,
             );
-            winuser::UpdateWindow(self.window.0);
+            winuser::InvalidateRgn(self.window.0, ptr::null_mut(), 0);
         }
     }
 
@@ -217,8 +218,8 @@ impl Window {
 
     #[inline]
     pub fn set_inner_size(&self, size: Size) {
-        let dpi_factor = self.scale_factor();
-        let (width, height) = size.to_physical::<u32>(dpi_factor).into();
+        let scale_factor = self.scale_factor();
+        let (width, height) = size.to_physical::<u32>(scale_factor).into();
 
         let window_state = Arc::clone(&self.window_state);
         let window = self.window.clone();
@@ -325,13 +326,13 @@ impl Window {
 
     #[inline]
     pub fn scale_factor(&self) -> f64 {
-        self.window_state.lock().dpi_factor
+        self.window_state.lock().scale_factor
     }
 
     #[inline]
     pub fn set_cursor_position(&self, position: Position) -> Result<(), ExternalError> {
-        let dpi_factor = self.scale_factor();
-        let (x, y) = position.to_physical::<i32>(dpi_factor).into();
+        let scale_factor = self.scale_factor();
+        let (x, y) = position.to_physical::<i32>(scale_factor).into();
 
         let mut point = POINT { x, y };
         unsafe {
@@ -402,7 +403,7 @@ impl Window {
                     let client_rect = util::get_client_rect(window.0).unwrap();
                     window_state_lock.saved_window = Some(SavedWindow {
                         client_rect,
-                        dpi_factor: window_state_lock.dpi_factor,
+                        scale_factor: window_state_lock.scale_factor,
                     });
                 }
                 _ => (),
@@ -506,17 +507,17 @@ impl Window {
                             size.1 as i32,
                             winuser::SWP_ASYNCWINDOWPOS | winuser::SWP_NOZORDER,
                         );
-                        winuser::UpdateWindow(window.0);
+                        winuser::InvalidateRgn(window.0, ptr::null_mut(), 0);
                     }
                 }
                 None => {
                     let mut window_state_lock = window_state.lock();
                     if let Some(SavedWindow {
                         client_rect,
-                        dpi_factor,
+                        scale_factor,
                     }) = window_state_lock.saved_window.take()
                     {
-                        window_state_lock.dpi_factor = dpi_factor;
+                        window_state_lock.scale_factor = scale_factor;
                         drop(window_state_lock);
                         let client_rect = util::adjust_window_rect(window.0, client_rect).unwrap();
 
@@ -532,7 +533,7 @@ impl Window {
                                     | winuser::SWP_NOZORDER
                                     | winuser::SWP_NOACTIVATE,
                             );
-                            winuser::UpdateWindow(window.0);
+                            winuser::InvalidateRgn(window.0, ptr::null_mut(), 0);
                         }
                     }
                 }
@@ -576,12 +577,11 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_window_icon(&self, mut window_icon: Option<Icon>) {
-        let window_icon = window_icon
-            .take()
-            .map(|icon| WinIcon::from_icon(icon).expect("Failed to create `ICON_SMALL`"));
+    pub fn set_window_icon(&self, window_icon: Option<Icon>) {
         if let Some(ref window_icon) = window_icon {
-            window_icon.set_for_window(self.window.0, IconType::Small);
+            window_icon
+                .inner
+                .set_for_window(self.window.0, IconType::Small);
         } else {
             icon::unset_for_window(self.window.0, IconType::Small);
         }
@@ -589,12 +589,11 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_taskbar_icon(&self, mut taskbar_icon: Option<Icon>) {
-        let taskbar_icon = taskbar_icon
-            .take()
-            .map(|icon| WinIcon::from_icon(icon).expect("Failed to create `ICON_BIG`"));
+    pub fn set_taskbar_icon(&self, taskbar_icon: Option<Icon>) {
         if let Some(ref taskbar_icon) = taskbar_icon {
-            taskbar_icon.set_for_window(self.window.0, IconType::Big);
+            taskbar_icon
+                .inner
+                .set_for_window(self.window.0, IconType::Big);
         } else {
             icon::unset_for_window(self.window.0, IconType::Big);
         }
@@ -636,7 +635,7 @@ unsafe impl Sync for WindowWrapper {}
 unsafe impl Send for WindowWrapper {}
 
 unsafe fn init<T: 'static>(
-    mut attributes: WindowAttributes,
+    attributes: WindowAttributes,
     pl_attribs: PlatformSpecificWindowBuilderAttributes,
     event_loop: &EventLoopWindowTarget<T>,
 ) -> Result<Window, RootOsError> {
@@ -645,25 +644,8 @@ unsafe fn init<T: 'static>(
         .chain(Some(0).into_iter())
         .collect::<Vec<_>>();
 
-    let window_icon = {
-        let icon = attributes.window_icon.take().map(WinIcon::from_icon);
-        if let Some(icon) = icon {
-            Some(icon.map_err(|e| os_error!(e))?)
-        } else {
-            None
-        }
-    };
-    let taskbar_icon = {
-        let icon = attributes.window_icon.take().map(WinIcon::from_icon);
-        if let Some(icon) = icon {
-            Some(icon.map_err(|e| os_error!(e))?)
-        } else {
-            None
-        }
-    };
-
     // registering the window class
-    let class_name = register_window_class(&window_icon, &taskbar_icon);
+    let class_name = register_window_class(&attributes.window_icon, &pl_attribs.taskbar_icon);
 
     let mut window_flags = WindowFlags::empty();
     window_flags.set(WindowFlags::DECORATIONS, attributes.decorations);
@@ -712,7 +694,7 @@ unsafe fn init<T: 'static>(
     }
 
     let dpi = hwnd_dpi(real_window.0);
-    let dpi_factor = dpi_to_scale_factor(dpi);
+    let scale_factor = dpi_to_scale_factor(dpi);
 
     // making the window transparent
     if attributes.transparent && !pl_attribs.no_redirection_bitmap {
@@ -746,8 +728,6 @@ unsafe fn init<T: 'static>(
         }
     }
 
-    window_flags.set(WindowFlags::MAXIMIZED, attributes.maximized);
-
     // If the system theme is dark, we need to set the window theme now
     // before we update the window flags (and possibly show the
     // window for the first time).
@@ -756,9 +736,8 @@ unsafe fn init<T: 'static>(
     let window_state = {
         let window_state = WindowState::new(
             &attributes,
-            window_icon,
-            taskbar_icon,
-            dpi_factor,
+            pl_attribs.taskbar_icon,
+            scale_factor,
             dark_mode,
         );
         let window_state = Arc::new(Mutex::new(window_state));
@@ -776,6 +755,11 @@ unsafe fn init<T: 'static>(
         .inner_size
         .unwrap_or_else(|| PhysicalSize::new(1024, 768).into());
     win.set_inner_size(dimensions);
+    if attributes.maximized {
+        // Need to set MAXIMIZED after setting `inner_size` as
+        // `Window::set_inner_size` changes MAXIMIZED to false.
+        win.set_maximized(true);
+    }
     win.set_visible(attributes.visible);
 
     if let Some(_) = attributes.fullscreen {
@@ -787,8 +771,8 @@ unsafe fn init<T: 'static>(
 }
 
 unsafe fn register_window_class(
-    window_icon: &Option<WinIcon>,
-    taskbar_icon: &Option<WinIcon>,
+    window_icon: &Option<Icon>,
+    taskbar_icon: &Option<Icon>,
 ) -> Vec<u16> {
     let class_name: Vec<_> = OsStr::new("Window Class")
         .encode_wide()
@@ -797,11 +781,11 @@ unsafe fn register_window_class(
 
     let h_icon = taskbar_icon
         .as_ref()
-        .map(|icon| icon.handle)
+        .map(|icon| icon.inner.as_raw_handle())
         .unwrap_or(ptr::null_mut());
     let h_icon_small = window_icon
         .as_ref()
-        .map(|icon| icon.handle)
+        .map(|icon| icon.inner.as_raw_handle())
         .unwrap_or(ptr::null_mut());
 
     let class = winuser::WNDCLASSEXW {

src/platform_impl/windows/window_state.rs

@@ -1,6 +1,8 @@
 use crate::{
-    dpi::Size,
-    platform_impl::platform::{event_loop, icon::WinIcon, util},
+    dpi::{PhysicalPosition, Size},
+    event::ModifiersState,
+    icon::Icon,
+    platform_impl::platform::{event_loop, util},
     window::{CursorIcon, Fullscreen, WindowAttributes},
 };
 use parking_lot::MutexGuard;
@@ -14,7 +16,6 @@ use winapi::{
 };
 
 /// Contains information about states and the window that the callback is going to use.
-#[derive(Clone)]
 pub struct WindowState {
     pub mouse: MouseProperties,
 
@@ -22,16 +23,14 @@ pub struct WindowState {
     pub min_size: Option<Size>,
     pub max_size: Option<Size>,
 
-    pub window_icon: Option<WinIcon>,
-    pub taskbar_icon: Option<WinIcon>,
+    pub window_icon: Option<Icon>,
+    pub taskbar_icon: Option<Icon>,
 
     pub saved_window: Option<SavedWindow>,
-    pub dpi_factor: f64,
+    pub scale_factor: f64,
 
+    pub modifiers_state: ModifiersState,
     pub fullscreen: Option<Fullscreen>,
-    /// Used to supress duplicate redraw attempts when calling `request_redraw` multiple
-    /// times in `MainEventsCleared`.
-    pub queued_out_of_band_redraw: bool,
     pub is_dark_mode: bool,
     pub high_surrogate: Option<u16>,
     window_flags: WindowFlags,
@@ -40,7 +39,7 @@ pub struct WindowState {
 #[derive(Clone)]
 pub struct SavedWindow {
     pub client_rect: RECT,
-    pub dpi_factor: f64,
+    pub scale_factor: f64,
 }
 
 #[derive(Clone)]
@@ -48,6 +47,7 @@ pub struct MouseProperties {
     pub cursor: CursorIcon,
     pub buttons_down: u32,
     cursor_flags: CursorFlags,
+    pub last_position: Option<PhysicalPosition<f64>>,
 }
 
 bitflags! {
@@ -80,7 +80,9 @@ bitflags! {
         /// window's state to match our stored state. This controls whether to accept those changes.
         const MARKER_RETAIN_STATE_ON_SIZE = 1 << 10;
 
-        const MINIMIZED = 1 << 11;
+        const MARKER_IN_SIZE_MOVE = 1 << 11;
+
+        const MINIMIZED = 1 << 12;
 
         const FULLSCREEN_AND_MASK = !(
             WindowFlags::DECORATIONS.bits |
@@ -96,9 +98,8 @@ bitflags! {
 impl WindowState {
     pub fn new(
         attributes: &WindowAttributes,
-        window_icon: Option<WinIcon>,
-        taskbar_icon: Option<WinIcon>,
-        dpi_factor: f64,
+        taskbar_icon: Option<Icon>,
+        scale_factor: f64,
         is_dark_mode: bool,
     ) -> WindowState {
         WindowState {
@@ -106,19 +107,20 @@ impl WindowState {
                 cursor: CursorIcon::default(),
                 buttons_down: 0,
                 cursor_flags: CursorFlags::empty(),
+                last_position: None,
             },
 
             min_size: attributes.min_inner_size,
             max_size: attributes.max_inner_size,
 
-            window_icon,
+            window_icon: attributes.window_icon.clone(),
             taskbar_icon,
 
             saved_window: None,
-            dpi_factor,
+            scale_factor,
 
+            modifiers_state: ModifiersState::default(),
             fullscreen: None,
-            queued_out_of_band_redraw: false,
             is_dark_mode,
             high_surrogate: None,
             window_flags: WindowFlags::empty(),
@@ -268,7 +270,7 @@ impl WindowFlags {
                         | winuser::SWP_NOSIZE
                         | winuser::SWP_NOACTIVATE,
                 );
-                winuser::UpdateWindow(window);
+                winuser::InvalidateRgn(window, ptr::null_mut(), 0);
             }
         }
 

src/window.rs

@@ -9,7 +9,7 @@ use crate::{
     platform_impl,
 };
 
-pub use crate::icon::*;
+pub use crate::icon::{BadIcon, Icon};
 
 /// Represents a window.
 ///