Update to newest master

Signed-off-by: John Nunley <dev@notgull.net>

CHANGELOG.md

@@ -11,8 +11,12 @@ Unreleased` header.
 
 # Unreleased
 
-# 0.29.5
-
+- On Windows, macOS, X11, Wayland and Web, implement setting images as cursors. See the `custom_cursors.rs` example.
+  - Add `Window::set_custom_cursor`
+  - Add `CustomCursor`
+  - Add `CustomCursor::from_rgba` to allow creating cursor images from RGBA data.
+  - Add `CustomCursorExtWebSys::from_url` to allow loading cursor images from URLs.
+- On macOS, add services menu.
 - On macOS, remove spurious error logging when handling `Fn`.
 - On X11, fix an issue where floating point data from the server is
   misinterpreted during a drag and drop operation.
@@ -21,8 +25,8 @@ Unreleased` header.
 - On Wayland, disable Client Side Decorations when `wl_subcompositor` is not supported.
 - On X11, fix `Xft.dpi` detection from Xresources.
 - On Windows, fix consecutive calls to `window.set_fullscreen(Some(Fullscreen::Borderless(None)))` resulting in losing previous window state when eventually exiting fullscreen using `window.set_fullscreen(None)`.
-- On Wayland, fix resize being sent on focus change.
-- On Windows, fix `set_ime_cursor_area`.
+- On Web, remove queuing fullscreen request in absence of transient activation.
+- On Web, fix setting cursor icon overriding cursor visibility.
 
 # 0.29.4
 

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "winit"
-version = "0.29.5"
+version = "0.29.4"
 authors = ["The winit contributors", "Pierre Krieger <pierre.krieger1708@gmail.com>"]
 description = "Cross-platform window creation library."
 edition = "2021"
@@ -43,7 +43,7 @@ rustdoc-args = ["--cfg", "docsrs"]
 
 [features]
 default = ["rwh_06", "x11", "wayland", "wayland-dlopen", "wayland-csd-adwaita"]
-x11 = ["x11-dl", "bytemuck", "percent-encoding", "xkbcommon-dl/x11", "x11rb"]
+x11 = ["x11-dl", "bytemuck", "percent-encoding", "xkbcommon-dl/x11", "x11rb", "xim"]
 wayland = ["wayland-client", "wayland-backend", "wayland-protocols", "wayland-protocols-plasma", "sctk", "ahash", "memmap2"]
 wayland-dlopen = ["wayland-backend/dlopen"]
 wayland-csd-adwaita = ["sctk-adwaita", "sctk-adwaita/ab_glyph"]
@@ -167,6 +167,7 @@ wayland-protocols = { version = "0.31.0", features = [ "staging"], optional = tr
 wayland-protocols-plasma = { version = "0.2.0", features = [ "client" ], optional = true }
 x11-dl = { version = "2.18.5", optional = true }
 x11rb = { version = "0.13.0", default-features = false, features = ["allow-unsafe-code", "dl-libxcb", "randr", "resource_manager", "xinput", "xkb"], optional = true }
+xim = { version = "0.3.0", features = ["x11rb-client", "client"], optional = true }
 xkbcommon-dl = "0.4.0"
 
 [target.'cfg(target_os = "redox")'.dependencies]
@@ -179,6 +180,7 @@ version = "0.3.64"
 features = [
     'AbortController',
     'AbortSignal',
+    'Blob',
     'console',
     'CssStyleDeclaration',
     'Document',
@@ -190,6 +192,10 @@ features = [
     'FocusEvent',
     'HtmlCanvasElement',
     'HtmlElement',
+    'ImageBitmap',
+    'ImageBitmapOptions',
+    'ImageBitmapRenderingContext',
+    'ImageData',
     'IntersectionObserver',
     'IntersectionObserverEntry',
     'KeyboardEvent',
@@ -199,6 +205,7 @@ features = [
     'Node',
     'PageTransitionEvent',
     'PointerEvent',
+    'PremultiplyAlpha',
     'ResizeObserver',
     'ResizeObserverBoxOptions',
     'ResizeObserverEntry',
@@ -206,7 +213,8 @@ features = [
     'ResizeObserverSize',
     'VisibilityState',
     'Window',
-    'WheelEvent'
+    'WheelEvent',
+    'Url',
 ]
 
 [target.'cfg(target_family = "wasm")'.dependencies]
@@ -224,3 +232,6 @@ web-sys = { version = "0.3.22", features = ['CanvasRenderingContext2d'] }
 members = [
     "run-wasm",
 ]
+
+[patch.crates-io]
+xim = { git = "https://github.com/forkgull/xim-rs", branch = "x11rb-13" }

FEATURES.md

@@ -106,6 +106,7 @@ If your PR makes notable changes to Winit's features, please update this section
 - **Cursor locking**: Locking the cursor inside the window so it cannot move.
 - **Cursor confining**: Confining the cursor to the window bounds so it cannot leave them.
 - **Cursor icon**: Changing the cursor icon or hiding the cursor.
+- **Cursor image**: Changing the cursor to your own image.
 - **Cursor hittest**: Handle or ignore mouse events for a window.
 - **Touch events**: Single-touch events.
 - **Touch pressure**: Touch events contain information about the amount of force being applied.
@@ -206,6 +207,7 @@ Legend:
 |Cursor locking          |❌       |✔️      |❌       |✔️          |**N/A**|**N/A**|✔️        |❌      |
 |Cursor confining        |✔️       |❌      |✔️       |✔️          |**N/A**|**N/A**|❌       |❌      |
 |Cursor icon             |✔️       |✔️      |✔️       |✔️          |**N/A**|**N/A**|✔️        |**N/A** |
+|Cursor image            |✔️       |✔️      |✔️       |✔️          |**N/A**|**N/A**|✔️        |**N/A** |
 |Cursor hittest          |✔️       |✔️      |✔️       |✔️          |**N/A**|**N/A**|❌        |❌      |
 |Touch events            |✔️       |❌      |✔️       |✔️          |✔️    |✔️     |✔️        |**N/A** |
 |Touch pressure          |✔️       |❌      |❌       |❌          |❌    |✔️     |✔️        |**N/A** |

README.md

@@ -6,7 +6,7 @@
 
 ```toml
 [dependencies]
-winit = "0.29.5"
+winit = "0.29.4"
 ```
 
 ## [Documentation](https://docs.rs/winit)
@@ -156,7 +156,7 @@ For more details, refer to these `android-activity` [example applications](https
 
 If your application is currently based on `NativeActivity` via the `ndk-glue` crate and building with `cargo apk`, then the minimal changes would be:
 1. Remove `ndk-glue` from your `Cargo.toml`
-2. Enable the `"android-native-activity"` feature for Winit: `winit = { version = "0.29.5", features = [ "android-native-activity" ] }`
+2. Enable the `"android-native-activity"` feature for Winit: `winit = { version = "0.29.4", features = [ "android-native-activity" ] }`
 3. Add an `android_main` entrypoint (as above), instead of using the '`[ndk_glue::main]` proc macro from `ndk-macros` (optionally add a dependency on `android_logger` and initialize logging as above).
 4. Pass a clone of the `AndroidApp` that your application receives to Winit when building your event loop (as shown above).
 

clippy.toml

@@ -6,6 +6,7 @@ disallowed-methods = [
     { path = "web_sys::HtmlCanvasElement::set_height", reason = "Winit shouldn't touch the internal canvas size" },
     { path = "web_sys::Window::document", reason = "cache this to reduce calls to JS" },
     { path = "web_sys::Window::get_computed_style", reason = "cache this to reduce calls to JS" },
+    { path = "web_sys::HtmlElement::style", reason = "cache this to reduce calls to JS" },
     { path = "web_sys::Element::request_fullscreen", reason = "Doesn't account for compatibility with Safari" },
     { path = "web_sys::Document::exit_fullscreen", reason = "Doesn't account for compatibility with Safari" },
     { path = "web_sys::Document::fullscreen_element", reason = "Doesn't account for compatibility with Safari" },

examples/custom_cursors.rs

@@ -0,0 +1,92 @@
+#![allow(clippy::single_match, clippy::disallowed_methods)]
+
+#[cfg(not(wasm_platform))]
+use simple_logger::SimpleLogger;
+use winit::{
+    event::{ElementState, Event, KeyEvent, WindowEvent},
+    event_loop::EventLoop,
+    keyboard::Key,
+    window::{CustomCursor, WindowBuilder},
+};
+
+fn decode_cursor(bytes: &[u8]) -> CustomCursor {
+    let img = image::load_from_memory(bytes).unwrap().to_rgba8();
+    let samples = img.into_flat_samples();
+    let (_, w, h) = samples.extents();
+    let (w, h) = (w as u16, h as u16);
+    CustomCursor::from_rgba(samples.samples, w, h, w / 2, h / 2).unwrap()
+}
+
+#[cfg(not(wasm_platform))]
+#[path = "util/fill.rs"]
+mod fill;
+
+fn main() -> Result<(), impl std::error::Error> {
+    #[cfg(not(wasm_platform))]
+    SimpleLogger::new()
+        .with_level(log::LevelFilter::Info)
+        .init()
+        .unwrap();
+    #[cfg(wasm_platform)]
+    console_log::init_with_level(log::Level::Debug).unwrap();
+
+    let event_loop = EventLoop::new().unwrap();
+    let builder = WindowBuilder::new().with_title("A fantastic window!");
+    #[cfg(wasm_platform)]
+    let builder = {
+        use winit::platform::web::WindowBuilderExtWebSys;
+        builder.with_append(true)
+    };
+    let window = builder.build(&event_loop).unwrap();
+
+    let mut cursor_idx = 0;
+    let mut cursor_visible = true;
+
+    let custom_cursors = [
+        decode_cursor(include_bytes!("data/cross.png")),
+        decode_cursor(include_bytes!("data/cross2.png")),
+    ];
+
+    event_loop.run(move |event, _elwt| match event {
+        Event::WindowEvent { event, .. } => match event {
+            WindowEvent::KeyboardInput {
+                event:
+                    KeyEvent {
+                        state: ElementState::Pressed,
+                        logical_key: key,
+                        ..
+                    },
+                ..
+            } => match key.as_ref() {
+                Key::Character("1") => {
+                    log::debug!("Setting cursor to {:?}", cursor_idx);
+                    window.set_custom_cursor(&custom_cursors[cursor_idx]);
+                    cursor_idx = (cursor_idx + 1) % 2;
+                }
+                Key::Character("2") => {
+                    log::debug!("Setting cursor icon to default");
+                    window.set_cursor_icon(Default::default());
+                }
+                Key::Character("3") => {
+                    cursor_visible = !cursor_visible;
+                    log::debug!("Setting cursor visibility to {:?}", cursor_visible);
+                    window.set_cursor_visible(cursor_visible);
+                }
+                _ => {}
+            },
+            WindowEvent::RedrawRequested => {
+                #[cfg(not(wasm_platform))]
+                fill::fill_window(&window);
+            }
+            WindowEvent::CloseRequested => {
+                #[cfg(not(wasm_platform))]
+                _elwt.exit();
+            }
+            _ => (),
+        },
+        Event::AboutToWait => {
+            window.request_redraw();
+        }
+        _ => {}
+    })
+}

src/cursor.rs

@@ -0,0 +1,198 @@
+use core::fmt;
+use std::{error::Error, sync::Arc};
+
+use crate::platform_impl::PlatformCustomCursor;
+
+/// The maximum width and height for a cursor when using [`CustomCursor::from_rgba`].
+pub const MAX_CURSOR_SIZE: u16 = 2048;
+
+const PIXEL_SIZE: usize = 4;
+
+/// Use a custom image as a cursor (mouse pointer).
+///
+/// ## Platform-specific
+///
+/// **Web**: Some browsers have limits on cursor sizes usually at 128x128.
+///
+/// # Example
+///
+/// ```
+/// use winit::window::CustomCursor;
+///
+/// let w = 10;
+/// let h = 10;
+/// let rgba = vec![255; (w * h * 4) as usize];
+/// let custom_cursor = CustomCursor::from_rgba(rgba, w, h, w / 2, h / 2).unwrap();
+///
+/// #[cfg(target_family = "wasm")]
+/// let custom_cursor_url = {
+///     use winit::platform::web::CustomCursorExtWebSys;
+///     CustomCursor::from_url("http://localhost:3000/cursor.png", 0, 0).unwrap()
+/// };
+/// ```
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct CustomCursor {
+    pub(crate) inner: Arc<PlatformCustomCursor>,
+}
+
+impl CustomCursor {
+    /// Creates a new cursor from an rgba buffer.
+    ///
+    /// ## Platform-specific
+    ///
+    /// - **Web:** Setting cursor could be delayed due to the creation of `Blob` objects,
+    ///   which are async by nature.
+    pub fn from_rgba(
+        rgba: impl Into<Vec<u8>>,
+        width: u16,
+        height: u16,
+        hotspot_x: u16,
+        hotspot_y: u16,
+    ) -> Result<Self, BadImage> {
+        Ok(Self {
+            inner: PlatformCustomCursor::from_rgba(
+                rgba.into(),
+                width,
+                height,
+                hotspot_x,
+                hotspot_y,
+            )?
+            .into(),
+        })
+    }
+}
+
+/// An error produced when using [`CustomCursor::from_rgba`] with invalid arguments.
+#[derive(Debug, Clone)]
+pub enum BadImage {
+    /// Produced when the image dimensions are larger than [`MAX_CURSOR_SIZE`]. This doesn't
+    /// guarantee that the cursor will work, but should avoid many platform and device specific
+    /// limits.
+    TooLarge { width: u16, height: u16 },
+    /// Produced when the length of the `rgba` argument isn't divisible by 4, thus `rgba` can't be
+    /// safely interpreted as 32bpp RGBA pixels.
+    ByteCountNotDivisibleBy4 { byte_count: usize },
+    /// Produced when the number of pixels (`rgba.len() / 4`) isn't equal to `width * height`.
+    /// At least one of your arguments is incorrect.
+    DimensionsVsPixelCount {
+        width: u16,
+        height: u16,
+        width_x_height: u64,
+        pixel_count: u64,
+    },
+    /// Produced when the hotspot is outside the image bounds
+    HotspotOutOfBounds {
+        width: u16,
+        height: u16,
+        hotspot_x: u16,
+        hotspot_y: u16,
+    },
+}
+
+impl fmt::Display for BadImage {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            BadImage::TooLarge { width, height } => write!(f,
+                "The specified dimensions ({width:?}x{height:?}) are too large. The maximum is {MAX_CURSOR_SIZE:?}x{MAX_CURSOR_SIZE:?}.",
+            ),
+            BadImage::ByteCountNotDivisibleBy4 { byte_count } => write!(f,
+                "The length of the `rgba` argument ({byte_count:?}) isn't divisible by 4, making it impossible to interpret as 32bpp RGBA pixels.",
+            ),
+            BadImage::DimensionsVsPixelCount {
+                width,
+                height,
+                width_x_height,
+                pixel_count,
+            } => write!(f,
+                "The specified dimensions ({width:?}x{height:?}) don't match the number of pixels supplied by the `rgba` argument ({pixel_count:?}). For those dimensions, the expected pixel count is {width_x_height:?}.",
+            ),
+            BadImage::HotspotOutOfBounds {
+                width,
+                height,
+                hotspot_x,
+                hotspot_y,
+            } => write!(f,
+                "The specified hotspot ({hotspot_x:?}, {hotspot_y:?}) is outside the image bounds ({width:?}x{height:?}).",
+            ),
+        }
+    }
+}
+
+impl Error for BadImage {}
+
+/// Platforms export this directly as `PlatformCustomCursor` if they need to only work with images.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct CursorImage {
+    pub(crate) rgba: Vec<u8>,
+    pub(crate) width: u16,
+    pub(crate) height: u16,
+    pub(crate) hotspot_x: u16,
+    pub(crate) hotspot_y: u16,
+}
+
+#[allow(dead_code)]
+impl CursorImage {
+    pub fn from_rgba(
+        rgba: Vec<u8>,
+        width: u16,
+        height: u16,
+        hotspot_x: u16,
+        hotspot_y: u16,
+    ) -> Result<Self, BadImage> {
+        if width > MAX_CURSOR_SIZE || height > MAX_CURSOR_SIZE {
+            return Err(BadImage::TooLarge { width, height });
+        }
+
+        if rgba.len() % PIXEL_SIZE != 0 {
+            return Err(BadImage::ByteCountNotDivisibleBy4 {
+                byte_count: rgba.len(),
+            });
+        }
+
+        let pixel_count = (rgba.len() / PIXEL_SIZE) as u64;
+        let width_x_height = width as u64 * height as u64;
+        if pixel_count != width_x_height {
+            return Err(BadImage::DimensionsVsPixelCount {
+                width,
+                height,
+                width_x_height,
+                pixel_count,
+            });
+        }
+
+        if hotspot_x >= width || hotspot_y >= height {
+            return Err(BadImage::HotspotOutOfBounds {
+                width,
+                height,
+                hotspot_x,
+                hotspot_y,
+            });
+        }
+
+        Ok(CursorImage {
+            rgba,
+            width,
+            height,
+            hotspot_x,
+            hotspot_y,
+        })
+    }
+}
+
+// Platforms that don't support cursors will export this as `PlatformCustomCursor`.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub(crate) struct NoCustomCursor;
+
+#[allow(dead_code)]
+impl NoCustomCursor {
+    pub fn from_rgba(
+        rgba: Vec<u8>,
+        width: u16,
+        height: u16,
+        hotspot_x: u16,
+        hotspot_y: u16,
+    ) -> Result<Self, BadImage> {
+        CursorImage::from_rgba(rgba, width, height, hotspot_x, hotspot_y)?;
+        Ok(Self)
+    }
+}

src/lib.rs

@@ -172,6 +172,7 @@ extern crate bitflags;
 pub mod dpi;
 #[macro_use]
 pub mod error;
+mod cursor;
 pub mod event;
 pub mod event_loop;
 mod icon;

src/platform/web.rs

@@ -27,9 +27,11 @@
 //! [`border`]: https://developer.mozilla.org/en-US/docs/Web/CSS/border
 //! [`padding`]: https://developer.mozilla.org/en-US/docs/Web/CSS/padding
 
+use crate::cursor::CustomCursor;
 use crate::event::Event;
 use crate::event_loop::EventLoop;
 use crate::event_loop::EventLoopWindowTarget;
+use crate::platform_impl::PlatformCustomCursor;
 use crate::window::{Window, WindowBuilder};
 use crate::SendSyncWrapper;
 
@@ -200,3 +202,25 @@ pub enum PollStrategy {
     #[default]
     Scheduler,
 }
+
+pub trait CustomCursorExtWebSys {
+    /// Creates a new cursor from a URL pointing to an image.
+    /// It uses the [url css function](https://developer.mozilla.org/en-US/docs/Web/CSS/url),
+    /// but browser support for image formats is inconsistent. Using [PNG] is recommended.
+    ///
+    /// [PNG]: https://en.wikipedia.org/wiki/PNG
+    fn from_url(url: String, hotspot_x: u16, hotspot_y: u16) -> Self;
+}
+
+impl CustomCursorExtWebSys for CustomCursor {
+    fn from_url(url: String, hotspot_x: u16, hotspot_y: u16) -> Self {
+        Self {
+            inner: PlatformCustomCursor::Url {
+                url,
+                hotspot_x,
+                hotspot_y,
+            }
+            .into(),
+        }
+    }
+}

src/platform_impl/android/mod.rs

@@ -18,6 +18,7 @@ use android_activity::{
 use once_cell::sync::Lazy;
 
 use crate::{
+    cursor::CustomCursor,
     dpi::{PhysicalPosition, PhysicalSize, Position, Size},
     error,
     event::{self, Force, InnerSizeWriter, StartCause},
@@ -906,6 +907,8 @@ impl Window {
 
     pub fn set_cursor_icon(&self, _: window::CursorIcon) {}
 
+    pub fn set_custom_cursor(&self, _: CustomCursor) {}
+
     pub fn set_cursor_position(&self, _: Position) -> Result<(), error::ExternalError> {
         Err(error::ExternalError::NotSupported(
             error::NotSupportedError::new(),
@@ -1031,6 +1034,7 @@ impl Display for OsError {
     }
 }
 
+pub(crate) use crate::cursor::NoCustomCursor as PlatformCustomCursor;
 pub(crate) use crate::icon::NoIcon as PlatformIcon;
 
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]

src/platform_impl/ios/mod.rs

@@ -77,6 +77,7 @@ pub(crate) use self::{
 };
 
 use self::uikit::UIScreen;
+pub(crate) use crate::cursor::NoCustomCursor as PlatformCustomCursor;
 pub(crate) use crate::icon::NoIcon as PlatformIcon;
 pub(crate) use crate::platform_impl::Fullscreen;
 

src/platform_impl/ios/window.rs

@@ -11,6 +11,7 @@ use super::app_state::EventWrapper;
 use super::uikit::{UIApplication, UIScreen, UIScreenOverscanCompensation};
 use super::view::{WinitUIWindow, WinitView, WinitViewController};
 use crate::{
+    cursor::CustomCursor,
     dpi::{self, LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize, Position, Size},
     error::{ExternalError, NotSupportedError, OsError as RootOsError},
     event::{Event, WindowEvent},
@@ -177,6 +178,10 @@ impl Inner {
         debug!("`Window::set_cursor_icon` ignored on iOS")
     }
 
+    pub fn set_custom_cursor(&self, _: CustomCursor) {
+        debug!("`Window::set_custom_cursor` ignored on iOS")
+    }
+
     pub fn set_cursor_position(&self, _position: Position) -> Result<(), ExternalError> {
         Err(ExternalError::NotSupported(NotSupportedError::new()))
     }

src/platform_impl/linux/mod.rs

@@ -14,6 +14,7 @@ use std::{ffi::CStr, mem::MaybeUninit, os::raw::*, sync::Mutex};
 use once_cell::sync::Lazy;
 use smol_str::SmolStr;
 
+use crate::cursor::CustomCursor;
 #[cfg(x11_platform)]
 use crate::platform::x11::XlibErrorHook;
 use crate::{
@@ -40,6 +41,7 @@ pub use x11::XNotSupported;
 #[cfg(x11_platform)]
 use x11::{util::WindowType as XWindowType, X11Error, XConnection, XError};
 
+pub(crate) use crate::cursor::CursorImage as PlatformCustomCursor;
 pub(crate) use crate::icon::RgbaIcon as PlatformIcon;
 pub(crate) use crate::platform_impl::Fullscreen;
 
@@ -424,6 +426,11 @@ impl Window {
         x11_or_wayland!(match self; Window(w) => w.set_cursor_icon(cursor))
     }
 
+    #[inline]
+    pub fn set_custom_cursor(&self, cursor: CustomCursor) {
+        x11_or_wayland!(match self; Window(w) => w.set_custom_cursor(cursor))
+    }
+
     #[inline]
     pub fn set_cursor_grab(&self, mode: CursorGrabMode) -> Result<(), ExternalError> {
         x11_or_wayland!(match self; Window(window) => window.set_cursor_grab(mode))

src/platform_impl/linux/wayland/state.rs

@@ -19,6 +19,7 @@ use sctk::seat::SeatState;
 use sctk::shell::xdg::window::{Window, WindowConfigure, WindowHandler};
 use sctk::shell::xdg::XdgShell;
 use sctk::shell::WaylandSurface;
+use sctk::shm::slot::SlotPool;
 use sctk::shm::{Shm, ShmHandler};
 use sctk::subcompositor::SubcompositorState;
 
@@ -58,6 +59,9 @@ pub struct WinitState {
     /// The shm for software buffers, such as cursors.
     pub shm: Shm,
 
+    /// The pool where custom cursors are allocated.
+    pub custom_cursor_pool: Arc<Mutex<SlotPool>>,
+
     /// The XDG shell that is used for widnows.
     pub xdg_shell: XdgShell,
 
@@ -153,13 +157,17 @@ impl WinitState {
                 (None, None)
             };
 
+        let shm = Shm::bind(globals, queue_handle).map_err(WaylandError::Bind)?;
+        let custom_cursor_pool = Arc::new(Mutex::new(SlotPool::new(2, &shm).unwrap()));
+
         Ok(Self {
             registry_state,
             compositor_state: Arc::new(compositor_state),
             subcompositor_state: subcompositor_state.map(Arc::new),
             output_state,
             seat_state,
-            shm: Shm::bind(globals, queue_handle).map_err(WaylandError::Bind)?,
+            shm,
+            custom_cursor_pool,
 
             xdg_shell: XdgShell::bind(globals, queue_handle).map_err(WaylandError::Bind)?,
             xdg_activation: XdgActivationState::bind(globals, queue_handle).ok(),
@@ -299,11 +307,7 @@ impl WindowHandler for WinitState {
                 &mut self.events_sink,
             );
 
-        // NOTE: Only update when the value is `Some` to not override consequent configures with
-        // the same sizes.
-        if new_size.is_some() {
-            self.window_compositor_updates[pos].size = new_size;
-        }
+        self.window_compositor_updates[pos].size = Some(new_size);
     }
 }
 

src/platform_impl/linux/wayland/types/cursor.rs

@@ -0,0 +1,56 @@
+use cursor_icon::CursorIcon;
+
+use sctk::reexports::client::protocol::wl_shm::Format;
+use sctk::shm::slot::{Buffer, SlotPool};
+
+use crate::cursor::CursorImage;
+
+#[derive(Debug)]
+pub enum SelectedCursor {
+    Named(CursorIcon),
+    Custom(CustomCursor),
+}
+
+impl Default for SelectedCursor {
+    fn default() -> Self {
+        Self::Named(Default::default())
+    }
+}
+
+#[derive(Debug)]
+pub struct CustomCursor {
+    pub buffer: Buffer,
+    pub w: i32,
+    pub h: i32,
+    pub hotspot_x: i32,
+    pub hotspot_y: i32,
+}
+
+impl CustomCursor {
+    pub fn new(pool: &mut SlotPool, image: &CursorImage) -> Self {
+        let (buffer, canvas) = pool
+            .create_buffer(
+                image.width as i32,
+                image.height as i32,
+                4 * (image.width as i32),
+                Format::Argb8888,
+            )
+            .unwrap();
+
+        for (canvas_chunk, rgba_chunk) in canvas.chunks_exact_mut(4).zip(image.rgba.chunks_exact(4))
+        {
+            canvas_chunk[0] = rgba_chunk[2];
+            canvas_chunk[1] = rgba_chunk[1];
+            canvas_chunk[2] = rgba_chunk[0];
+            canvas_chunk[3] = rgba_chunk[3];
+        }
+
+        CustomCursor {
+            buffer,
+            w: image.width as i32,
+            h: image.height as i32,
+            hotspot_x: image.hotspot_x as i32,
+            hotspot_y: image.hotspot_y as i32,
+        }
+    }
+}

src/platform_impl/linux/wayland/types/mod.rs

@@ -1,5 +1,6 @@
 //! Wayland protocol implementation boilerplate.
 
+pub mod cursor;
 pub mod kwin_blur;
 pub mod wp_fractional_scaling;
 pub mod wp_viewporter;

src/platform_impl/linux/wayland/window/mod.rs

@@ -15,6 +15,7 @@ use sctk::shell::xdg::window::Window as SctkWindow;
 use sctk::shell::xdg::window::WindowDecorations;
 use sctk::shell::WaylandSurface;
 
+use crate::cursor::CustomCursor;
 use crate::dpi::{LogicalSize, PhysicalPosition, PhysicalSize, Position, Size};
 use crate::error::{ExternalError, NotSupportedError, OsError as RootOsError};
 use crate::event::{Ime, WindowEvent};
@@ -506,6 +507,11 @@ impl Window {
         self.window_state.lock().unwrap().set_cursor(cursor);
     }
 
+    #[inline]
+    pub fn set_custom_cursor(&self, cursor: CustomCursor) {
+        self.window_state.lock().unwrap().set_custom_cursor(cursor);
+    }
+
     #[inline]
     pub fn set_cursor_visible(&self, visible: bool) {
         self.window_state

src/platform_impl/linux/wayland/window/state.rs

@@ -1,7 +1,7 @@
 //! The state of the window, which is shared with the event-loop.
 
 use std::num::NonZeroU32;
-use std::sync::{Arc, Weak};
+use std::sync::{Arc, Mutex, Weak};
 use std::time::Duration;
 
 use log::{info, warn};
@@ -18,20 +18,23 @@ use sctk::reexports::protocols::wp::text_input::zv3::client::zwp_text_input_v3::
 use sctk::reexports::protocols::wp::viewporter::client::wp_viewport::WpViewport;
 use sctk::reexports::protocols::xdg::shell::client::xdg_toplevel::ResizeEdge as XdgResizeEdge;
 
-use sctk::compositor::{CompositorState, Region};
-use sctk::seat::pointer::ThemedPointer;
+use sctk::compositor::{CompositorState, Region, SurfaceData, SurfaceDataExt};
+use sctk::seat::pointer::{PointerDataExt, ThemedPointer};
 use sctk::shell::xdg::window::{DecorationMode, Window, WindowConfigure};
 use sctk::shell::xdg::XdgSurface;
 use sctk::shell::WaylandSurface;
+use sctk::shm::slot::SlotPool;
 use sctk::shm::Shm;
 use sctk::subcompositor::SubcompositorState;
 use wayland_protocols_plasma::blur::client::org_kde_kwin_blur::OrgKdeKwinBlur;
 
+use crate::cursor::CustomCursor as RootCustomCursor;
 use crate::dpi::{LogicalPosition, LogicalSize, PhysicalSize, Size};
 use crate::error::{ExternalError, NotSupportedError};
 use crate::event::WindowEvent;
 use crate::platform_impl::wayland::event_loop::sink::EventSink;
 use crate::platform_impl::wayland::make_wid;
+use crate::platform_impl::wayland::types::cursor::{CustomCursor, SelectedCursor};
 use crate::platform_impl::wayland::types::kwin_blur::KWinBlurManager;
 use crate::platform_impl::WindowId;
 use crate::window::{CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme};
@@ -60,14 +63,16 @@ pub struct WindowState {
     /// The `Shm` to set cursor.
     pub shm: WlShm,
 
+    // A shared pool where to allocate custom cursors.
+    custom_cursor_pool: Arc<Mutex<SlotPool>>,
+
     /// The last received configure.
     pub last_configure: Option<WindowConfigure>,
 
     /// The pointers observed on the window.
     pub pointers: Vec<Weak<ThemedPointer<WinitPointerData>>>,
 
-    /// Cursor icon.
-    pub cursor_icon: CursorIcon,
+    selected_cursor: SelectedCursor,
 
     /// Wether the cursor is visible.
     pub cursor_visible: bool,
@@ -178,7 +183,7 @@ impl WindowState {
             connection,
             csd_fails: false,
             cursor_grab_mode: GrabState::new(),
-            cursor_icon: CursorIcon::Default,
+            selected_cursor: Default::default(),
             cursor_visible: true,
             decorate: true,
             fractional_scale,
@@ -197,6 +202,7 @@ impl WindowState {
             resizable: true,
             scale_factor: 1.,
             shm: winit_state.shm.wl_shm().clone(),
+            custom_cursor_pool: winit_state.custom_cursor_pool.clone(),
             size: initial_size.to_logical(1.),
             stateless_size: initial_size.to_logical(1.),
             initial_size: Some(initial_size),
@@ -256,7 +262,7 @@ impl WindowState {
         shm: &Shm,
         subcompositor: &Option<Arc<SubcompositorState>>,
         event_sink: &mut EventSink,
-    ) -> Option<LogicalSize<u32>> {
+    ) -> LogicalSize<u32> {
         // NOTE: when using fractional scaling or wl_compositor@v6 the scaling
         // should be delivered before the first configure, thus apply it to
         // properly scale the physical sizes provided by the users.
@@ -319,9 +325,14 @@ impl WindowState {
             match configure.new_size {
                 (Some(width), Some(height)) => {
                     let (width, height) = frame.subtract_borders(width, height);
-                    let width = width.map(|w| w.get()).unwrap_or(1);
-                    let height = height.map(|h| h.get()).unwrap_or(1);
-                    ((width, height).into(), false)
+                    (
+                        (
+                            width.map(|w| w.get()).unwrap_or(1),
+                            height.map(|h| h.get()).unwrap_or(1),
+                        )
+                            .into(),
+                        false,
+                    )
                 }
                 (_, _) if stateless => (self.stateless_size, true),
                 _ => (self.size, true),
@@ -347,31 +358,13 @@ impl WindowState {
                 .unwrap_or(new_size.height);
         }
 
-        let new_state = configure.state;
-        let old_state = self
-            .last_configure
-            .as_ref()
-            .map(|configure| configure.state);
-
-        let state_change_requires_resize = old_state
-            .map(|old_state| {
-                !old_state
-                    .symmetric_difference(new_state)
-                    .difference(XdgWindowState::ACTIVATED | XdgWindowState::SUSPENDED)
-                    .is_empty()
-            })
-            // NOTE: `None` is present for the initial configure, thus we must always resize.
-            .unwrap_or(true);
-
-        // NOTE: Set the configure before doing a resize, since we query it during it.
+        // XXX Set the configure before doing a resize.
         self.last_configure = Some(configure);
 
-        if state_change_requires_resize || new_size != self.inner_size() {
-            self.resize(new_size);
-            Some(new_size)
-        } else {
-            None
-        }
+        // XXX Update the new size right away.
+        self.resize(new_size);
+
+        new_size
     }
 
     /// Compute the bounds for the inner size of the surface.
@@ -616,7 +609,10 @@ impl WindowState {
     /// Reload the cursor style on the given window.
     pub fn reload_cursor_style(&mut self) {
         if self.cursor_visible {
-            self.set_cursor(self.cursor_icon);
+            match &self.selected_cursor {
+                SelectedCursor::Named(icon) => self.set_cursor(*icon),
+                SelectedCursor::Custom(cursor) => self.apply_custom_cursor(cursor),
+            }
         } else {
             self.set_cursor_visible(self.cursor_visible);
         }
@@ -702,10 +698,8 @@ impl WindowState {
     }
 
     /// Set the cursor icon.
-    ///
-    /// Providing `None` will hide the cursor.
     pub fn set_cursor(&mut self, cursor_icon: CursorIcon) {
-        self.cursor_icon = cursor_icon;
+        self.selected_cursor = SelectedCursor::Named(cursor_icon);
 
         if !self.cursor_visible {
             return;
@@ -718,6 +712,54 @@ impl WindowState {
         })
     }
 
+    /// Set the custom cursor icon.
+    pub fn set_custom_cursor(&mut self, cursor: RootCustomCursor) {
+        let cursor = {
+            let mut pool = self.custom_cursor_pool.lock().unwrap();
+            CustomCursor::new(&mut pool, &cursor.inner)
+        };
+
+        if self.cursor_visible {
+            self.apply_custom_cursor(&cursor);
+        }
+
+        self.selected_cursor = SelectedCursor::Custom(cursor);
+    }
+
+    fn apply_custom_cursor(&self, cursor: &CustomCursor) {
+        self.apply_on_poiner(|pointer, _| {
+            let surface = pointer.surface();
+
+            let scale = surface
+                .data::<SurfaceData>()
+                .unwrap()
+                .surface_data()
+                .scale_factor();
+
+            surface.set_buffer_scale(scale);
+            surface.attach(Some(cursor.buffer.wl_buffer()), 0, 0);
+            if surface.version() >= 4 {
+                surface.damage_buffer(0, 0, cursor.w, cursor.h);
+            } else {
+                surface.damage(0, 0, cursor.w / scale, cursor.h / scale);
+            }
+            surface.commit();
+
+            let serial = pointer
+                .pointer()
+                .data::<WinitPointerData>()
+                .and_then(|data| data.pointer_data().latest_enter_serial())
+                .unwrap();
+
+            pointer.pointer().set_cursor(
+                serial,
+                Some(surface),
+                cursor.hotspot_x / scale,
+                cursor.hotspot_y / scale,
+            );
+        });
+    }
+
     /// Set maximum inner window size.
     pub fn set_min_inner_size(&mut self, size: Option<LogicalSize<u32>>) {
         // Ensure that the window has the right minimum size.
@@ -852,7 +894,10 @@ impl WindowState {
         self.cursor_visible = cursor_visible;
 
         if self.cursor_visible {
-            self.set_cursor(self.cursor_icon);
+            match &self.selected_cursor {
+                SelectedCursor::Named(icon) => self.set_cursor(*icon),
+                SelectedCursor::Custom(cursor) => self.apply_custom_cursor(cursor),
+            }
         } else {
             for pointer in self.pointers.iter().filter_map(|pointer| pointer.upgrade()) {
                 let latest_enter_serial = pointer.pointer().winit_data().latest_enter_serial();
@@ -925,7 +970,7 @@ impl WindowState {
 
     /// Set the IME position.
     pub fn set_ime_cursor_area(&self, position: LogicalPosition<u32>, size: LogicalSize<u32>) {
-        // FIXME: This won't fly unless user will have a way to request IME window per seat, since
+        // XXX This won't fly unless user will have a way to request IME window per seat, since
         // the ime windows will be overlapping, but winit doesn't expose API to specify for
         // which seat we're setting IME position.
         let (x, y) = (position.x as i32, position.y as i32);
@@ -956,7 +1001,7 @@ impl WindowState {
     pub fn set_scale_factor(&mut self, scale_factor: f64) {
         self.scale_factor = scale_factor;
 
-        // NOTE: When fractional scaling is not used update the buffer scale.
+        // XXX when fractional scaling is not used update the buffer scale.
         if self.fractional_scale.is_none() {
             let _ = self.window.set_buffer_scale(self.scale_factor as _);
         }
@@ -1104,7 +1149,7 @@ impl From<ResizeDirection> for XdgResizeEdge {
     }
 }
 
-// NOTE: Rust doesn't allow `From<Option<Theme>>`.
+// XXX rust doesn't allow from `Option`.
 #[cfg(feature = "sctk-adwaita")]
 fn into_sctk_adwaita_config(theme: Option<Theme>) -> sctk_adwaita::FrameConfig {
     match theme {

src/platform_impl/linux/x11/atoms.rs

@@ -40,7 +40,6 @@ atom_manager! {
     WM_DELETE_WINDOW,
     WM_PROTOCOLS,
     WM_STATE,
-    XIM_SERVERS,
 
     // Assorted ICCCM Atoms
     _NET_WM_ICON,

src/platform_impl/linux/x11/dnd.rs

@@ -44,7 +44,7 @@ impl From<io::Error> for DndDataParseError {
 pub(crate) struct Dnd {
     xconn: Arc<XConnection>,
     // Populated by XdndEnter event handler
-    pub version: Option<c_long>,
+    pub version: Option<u32>,
     pub type_list: Option<Vec<xproto::Atom>>,
     // Populated by XdndPosition event handler
     pub source_window: Option<xproto::Window>,

src/platform_impl/linux/x11/ime.rs

@@ -0,0 +1,862 @@
+//! IME handler, using the xim-rs crate.
+
+use super::{X11Error, X11rbConnection, XConnection};
+
+use x11rb::connection::Connection;
+use x11rb::protocol::xproto::Window;
+use x11rb::protocol::Event;
+
+use xim::x11rb::{HasConnection, X11rbClient};
+use xim::{AttributeName, Client as _, ClientError, ClientHandler, InputStyle, Point};
+
+use std::cell::RefCell;
+use std::collections::{HashMap, VecDeque};
+use std::fmt;
+use std::rc::Rc;
+use std::sync::Arc;
+
+impl HasConnection for XConnection {
+    type Connection = X11rbConnection;
+
+    fn conn(&self) -> &Self::Connection {
+        self.xcb_connection()
+    }
+}
+
+/// A collection of the IME events that can occur.
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub enum ImeEvent {
+    Enabled,
+    Start,
+    Update(String, Option<usize>),
+    Commit(String),
+    End,
+    Disabled,
+}
+
+/// Invalid states that an IME client can enter.
+#[derive(Debug, Clone)]
+pub enum InvalidImeState {
+    /// The IME has no style information.
+    NoStyle,
+
+    /// No windows in the pending window queue.
+    NoWindows,
+
+    /// Invalid input context.
+    InvalidIc(u16),
+}
+
+impl fmt::Display for InvalidImeState {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            InvalidImeState::NoStyle => write!(f, "IME has no style information"),
+            InvalidImeState::NoWindows => {
+                write!(f, "IME has no windows in the pending window queue")
+            }
+            InvalidImeState::InvalidIc(ic) => write!(f, "IME has invalid input context {}", ic),
+        }
+    }
+}
+
+/// Request to control XIM handler from the window.
+pub enum ImeRequest {
+    /// Set IME spot position for given `window_id`.
+    Position(Window, i16, i16),
+
+    /// Allow IME input for the given `window_id`.
+    Allow(Window, bool),
+}
+
+/// The IME data for winit.
+pub(super) struct ImeData {
+    /// The XIM client manager.
+    client: X11rbClient<Arc<XConnection>>,
+
+    /// Relevant IME data.
+    handler: ImeHandler,
+}
+
+/// Inner IME handler.
+struct ImeHandler {
+    /// Handle to the event queue.
+    event_queue: Rc<RefCell<VecDeque<Event>>>,
+
+    /// Whether IME is currently disconnected.
+    disconnected: bool,
+
+    /// IME events waiting to be read.
+    ime_events: VecDeque<(Window, ImeEvent)>,
+
+    /// Windows waiting to be assigned an input context.
+    pending_windows: VecDeque<WindowData>,
+
+    /// Currently registered input styles.
+    styles: Option<(Style, Style)>,
+
+    /// The input method for the display, if there is one.
+    input_method: Option<u16>,
+
+    /// Hash map between input contexts and their associated data.
+    input_contexts: HashMap<u16, IcData>,
+
+    /// Map between window IDs and their associated input contexts.
+    window_contexts: HashMap<Window, u16>,
+}
+
+/// Data relevant for each input context.
+struct IcData {
+    /// Data associated with the window.
+    window: WindowData,
+
+    /// Newly set point for the context.
+    new_spot: Option<Point>,
+
+    /// The current preedit string.
+    ///
+    /// We use a `Vec<char>` here instead of a string because the IME indices operate on chars,
+    /// not bytes.
+    text: Vec<char>,
+
+    /// The current cursor position in the preedit string.
+    cursor: usize,
+}
+
+/// Windows waiting for IME events.
+struct WindowData {
+    /// The window ID.
+    id: Window,
+
+    /// The style of the window.
+    style: Style,
+
+    /// Current "spot" for the context.
+    spot: Point,
+}
+
+#[derive(Copy, Clone)]
+enum Style {
+    Preedit,
+    Nothing,
+    None,
+}
+
+impl ImeData {
+    /// Creates the IME data for the display.
+    pub(super) fn new(
+        conn: &Arc<XConnection>,
+        screen: usize,
+        event_queue: &Rc<RefCell<VecDeque<Event>>>,
+    ) -> Result<Self, X11Error> {
+        // IM servers to try, in order:
+        //  - None, which defaults to the environment variable `XMODIFIERS` in xim's impl.
+        //  - "local", which is the default for most IMEs.
+        //  - empty string, which may work in some cases.
+        let input_methods = [None, Some("local"), Some("")];
+        let mut last_error = X11Error::Ime(ClientError::NoXimServer);
+
+        for im in input_methods {
+            // Try to initialize a client here.
+            match X11rbClient::init(conn.clone(), screen, im) {
+                Ok(client) => {
+                    return Ok(Self {
+                        client,
+                        handler: ImeHandler {
+                            event_queue: event_queue.clone(),
+                            disconnected: true,
+                            ime_events: VecDeque::new(),
+                            pending_windows: VecDeque::new(),
+                            styles: None,
+                            input_method: None,
+                            input_contexts: HashMap::new(),
+                            window_contexts: HashMap::new(),
+                        },
+                    })
+                }
+
+                Err(err) => {
+                    log::warn!("Failed to create XIM client for {:?}: {err}", ImData(im));
+                    last_error = X11Error::Ime(err);
+                }
+            }
+        }
+
+        Err(last_error)
+    }
+
+    /// Filter an event.
+    pub(super) fn filter_event(&mut self, event: &Event) -> Result<bool, X11Error> {
+        self.client
+            .filter_event(event, &mut self.handler)
+            .map_err(X11Error::Ime)
+    }
+
+    /// Connection to the X server.
+    fn conn(&self) -> &X11rbConnection {
+        self.client.conn()
+    }
+
+    /// Get an IME event.
+    pub(super) fn next_ime_event(&mut self) -> Option<(Window, ImeEvent)> {
+        self.handler.ime_events.pop_front()
+    }
+
+    /// Create a new IME context for the provided window.
+    pub(super) fn create_context(
+        &mut self,
+        window: Window,
+        with_preedit: bool,
+        spot: Option<Point>,
+    ) -> Result<bool, X11Error> {
+        // If we aren't connected, nothing can be done.
+        if self.handler.disconnected {
+            return Ok(false);
+        }
+        let method = match self.handler.input_method {
+            Some(im) => im,
+            None => return Ok(false),
+        };
+
+        // Get the current style.
+        let style = match (self.handler.styles, with_preedit) {
+            (None, _) => return Err(X11Error::InvalidImeState(InvalidImeState::NoStyle)),
+            (Some((preedit_style, _)), true) => preedit_style,
+            (Some((_, none_style)), false) => none_style,
+        };
+
+        // Setup IC attributes.
+        let ic_attributes = {
+            let mut ic_attributes = self
+                .client
+                .build_ic_attributes()
+                .push(AttributeName::ClientWindow, window);
+
+            let ic_style = match style {
+                Style::Preedit => InputStyle::PREEDIT_POSITION | InputStyle::STATUS_NOTHING,
+                Style::Nothing => InputStyle::PREEDIT_NOTHING | InputStyle::STATUS_NOTHING,
+                Style::None => InputStyle::PREEDIT_NONE | InputStyle::STATUS_NONE,
+            };
+
+            if let Some(spot) = spot.clone() {
+                ic_attributes = ic_attributes.push(AttributeName::SpotLocation, spot);
+            }
+
+            ic_attributes
+                .push(AttributeName::InputStyle, ic_style)
+                .build()
+        };
+
+        // Create the IC.
+        self.client.create_ic(method, ic_attributes)?;
+
+        // Add to the waiting window list.
+        self.handler.pending_windows.push_back(WindowData {
+            id: window,
+            style,
+            spot: spot.unwrap_or(Point { x: 0, y: 0 }),
+        });
+
+        Ok(true)
+    }
+
+    /// Remove an IME context for a window.
+    pub(super) fn remove_context(&mut self, window: Window) -> Result<bool, X11Error> {
+        if self.handler.disconnected {
+            return Ok(false);
+        }
+        let method = match self.handler.input_method {
+            Some(im) => im,
+            None => return Ok(false),
+        };
+
+        // Remove the pending window if it's still pending.
+        let mut removed = false;
+        self.handler.pending_windows.retain(|pending| {
+            if pending.id == window {
+                removed = true;
+                false
+            } else {
+                true
+            }
+        });
+
+        if removed {
+            return Ok(true);
+        }
+
+        // Remove the IC if it's already created.
+        if let Some(ic) = self.handler.window_contexts.remove(&window) {
+            self.handler.input_contexts.remove(&ic);
+
+            // Destroy the IC.
+            self.client.destroy_ic(method, ic)?;
+        }
+
+        Ok(false)
+    }
+
+    /// Focus an IME context.
+    pub(super) fn focus_window(&mut self, window: Window) -> Result<bool, X11Error> {
+        if self.handler.disconnected {
+            return Ok(false);
+        }
+
+        let method = self.wait_for_method()?;
+        let ic = self.wait_for_context(window)?;
+
+        if let Some(ic) = ic {
+            self.client.set_focus(method, ic)?;
+            return Ok(true);
+        }
+
+        Ok(false)
+    }
+
+    /// Unfocus an IME context.
+    pub(super) fn unfocus_window(&mut self, window: Window) -> Result<bool, X11Error> {
+        if self.handler.disconnected {
+            return Ok(false);
+        }
+
+        let method = self.wait_for_method()?;
+        let ic = self.wait_for_context(window)?;
+
+        if let Some(ic) = ic {
+            self.client.unset_focus(method, ic)?;
+            return Ok(true);
+        }
+
+        Ok(false)
+    }
+
+    /// Set the spot for an IME context.
+    pub(super) fn set_spot(&mut self, window: Window, x: i16, y: i16) -> Result<(), X11Error> {
+        if self.handler.disconnected {
+            return Ok(());
+        }
+
+        let method = self.wait_for_method()?;
+        let ic = self.wait_for_context(window)?;
+
+        if let Some(ic) = ic {
+            // If the IC is not available, or if the spot is the same, then we don't need to update.
+            let ic_data = match self.handler.input_contexts.get_mut(&ic) {
+                Some(ic_data) => ic_data,
+                None => return Ok(()),
+            };
+
+            let new_point = Point { x, y };
+            if !matches!(ic_data.window.style, Style::None) || ic_data.window.spot == new_point {
+                return Ok(());
+            }
+
+            let new_attrs = self
+                .client
+                .build_ic_attributes()
+                .push(AttributeName::SpotLocation, new_point.clone())
+                .build();
+            self.client.set_ic_values(method, ic, new_attrs)?;
+
+            // Indicate that we have a new spot.
+            debug_assert!(ic_data.new_spot.is_none());
+            ic_data.new_spot = Some(new_point);
+        }
+
+        Ok(())
+    }
+
+    pub(super) fn set_ime_allowed(
+        &mut self,
+        window: Window,
+        allowed: bool,
+    ) -> Result<(), X11Error> {
+        if self.handler.disconnected {
+            return Ok(());
+        }
+
+        // Get the client info.
+        let _ = self.wait_for_method()?;
+        let ic = self.wait_for_context(window)?;
+
+        if let Some(ic) = ic {
+            let mut spot = None;
+
+            // See if we need to update the allowed state.
+            if let Some(ic_data) = self.handler.input_contexts.get(&ic) {
+                spot = Some(ic_data.window.spot.clone());
+                if matches!(ic_data.window.style, Style::None) != allowed {
+                    return Ok(());
+                }
+            }
+
+            // Delete and re-install the IC.
+            self.remove_context(window)?;
+            self.create_context(window, allowed, spot)?;
+        }
+
+        Ok(())
+    }
+
+    /// Wait for the input method to be set.
+    fn wait_for_method(&mut self) -> Result<u16, X11Error> {
+        loop {
+            if let Some(im) = self.handler.input_method {
+                return Ok(im);
+            }
+
+            // Wait and hope the input method is set.
+            self.block_for_ime()?;
+        }
+    }
+
+    /// Wait for an input context to be set.
+    fn wait_for_context(&mut self, window: Window) -> Result<Option<u16>, X11Error> {
+        if let Some(cid) = self.handler.window_contexts.get(&window) {
+            return Ok(Some(*cid));
+        }
+
+        // If the window isn't in our pending windows queue, there's no way for it to get an IC.
+        if !self
+            .handler
+            .pending_windows
+            .iter()
+            .any(|WindowData { id, .. }| *id == window)
+        {
+            return Ok(None);
+        }
+
+        loop {
+            self.block_for_ime()?;
+            if let Some(cid) = self.handler.window_contexts.get(&window) {
+                return Ok(Some(*cid));
+            }
+        }
+    }
+
+    /// Wait until we've acted on an IME event.
+    fn block_for_ime(&mut self) -> Result<(), X11Error> {
+        let mut last_event = self.conn().poll_for_event()?;
+
+        loop {
+            if let Some(last_event) = last_event.as_ref() {
+                if self.filter_event(last_event)? {
+                    return Ok(());
+                }
+            }
+
+            // This scope keeps track of the event queue handle.
+            {
+                // Check the event queue for events.
+                let event_queue = self.handler.event_queue.clone();
+                let mut event_queue = event_queue.borrow_mut();
+
+                // Check the event queue for events we can use.
+                let mut found_event = false;
+                let mut last_err = None;
+                event_queue.retain(|event| match self.filter_event(event) {
+                    Ok(false) => {
+                        found_event = true;
+                        true
+                    }
+                    Ok(true) => false,
+                    Err(err) => {
+                        last_err = Some(err);
+                        true
+                    }
+                });
+
+                // Push our own event to the queue.
+                if let Some(last_event) = last_event.take() {
+                    event_queue.push_back(last_event);
+                }
+
+                // Check for errors.
+                if let Some(err) = last_err {
+                    return Err(err);
+                }
+
+                // If we found an event, then we're done.
+                if found_event {
+                    return Ok(());
+                }
+            }
+
+            log::info!("Waiting for IME event");
+            last_event = Some(self.conn().wait_for_event()?);
+        }
+    }
+}
+
+impl<C: xim::Client> ClientHandler<C> for ImeHandler {
+    fn handle_connect(&mut self, client: &mut C) -> Result<(), ClientError> {
+        // We have been connected, now request a new input method for our current locale.
+        self.disconnected = false;
+        client.open(&locale())
+    }
+
+    fn handle_disconnect(&mut self) {
+        // We are now disconnected.
+        self.disconnected = true;
+    }
+
+    fn handle_open(&mut self, client: &mut C, input_method_id: u16) -> Result<(), ClientError> {
+        // We now have an input method.
+        debug_assert!(self.input_method.is_none());
+        self.input_method = Some(input_method_id);
+
+        // Ask for the IM's attributes.
+        client.get_im_values(input_method_id, &[AttributeName::QueryInputStyle])
+    }
+
+    fn handle_close(&mut self, _client: &mut C, input_method_id: u16) -> Result<(), ClientError> {
+        // No more input method.
+        debug_assert_eq!(self.input_method, Some(input_method_id));
+        self.input_method = None;
+
+        Ok(())
+    }
+
+    fn handle_get_im_values(
+        &mut self,
+        _client: &mut C,
+        input_method_id: u16,
+        mut attributes: xim::AHashMap<xim::AttributeName, Vec<u8>>,
+    ) -> Result<(), ClientError> {
+        debug_assert_eq!(self.input_method, Some(input_method_id));
+
+        // Get the input styles.
+        let mut preedit_style = None;
+        let mut none_style = None;
+
+        let styles = {
+            let style = attributes
+                .remove(&AttributeName::QueryInputStyle)
+                .expect("No query input style");
+            let mut result = vec![0u32; style.len() / 4];
+
+            bytemuck::cast_slice_mut::<u32, u8>(&mut result).copy_from_slice(&style);
+
+            result
+        };
+
+        {
+            // The styles that we're looking for.
+            let lu_preedit_style = InputStyle::PREEDIT_CALLBACKS | InputStyle::STATUS_NOTHING;
+            let lu_nothing_style = InputStyle::PREEDIT_NOTHING | InputStyle::STATUS_NOTHING;
+            let lu_none_style = InputStyle::PREEDIT_NONE | InputStyle::STATUS_NONE;
+
+            for style in styles {
+                let style = InputStyle::from_bits_truncate(style);
+
+                if style == lu_preedit_style {
+                    preedit_style = Some(Style::Preedit);
+                } else if style == lu_nothing_style {
+                    preedit_style = Some(Style::Nothing);
+                } else if style == lu_none_style {
+                    none_style = Some(Style::None);
+                }
+            }
+        }
+
+        let (preedit_style, none_style) = match (preedit_style, none_style) {
+            (None, None) => {
+                log::error!("No supported input styles found");
+                return Ok(());
+            }
+
+            (Some(style), None) | (None, Some(style)) => (style, style),
+
+            (Some(preedit_style), Some(none_style)) => (preedit_style, none_style),
+        };
+
+        self.styles = Some((preedit_style, none_style));
+
+        Ok(())
+    }
+
+    fn handle_create_ic(
+        &mut self,
+        _client: &mut C,
+        input_method_id: u16,
+        input_context_id: u16,
+    ) -> Result<(), ClientError> {
+        debug_assert_eq!(self.input_method, Some(input_method_id));
+
+        // Get the window that wanted the IC context.
+        let window = self
+            .pending_windows
+            .pop_front()
+            .ok_or_else(|| invalid_state(InvalidImeState::NoWindows))?;
+
+        // Create the IC data.
+        let ic_data = IcData {
+            window,
+            new_spot: None,
+            text: Vec::new(),
+            cursor: 0,
+        };
+
+        // Store the context.
+        let (window, style) = (ic_data.window.id, ic_data.window.style);
+        self.input_contexts.insert(input_context_id, ic_data);
+        self.window_contexts.insert(window, input_context_id);
+
+        // Indicate our status.
+        let event = if matches!(style, Style::Nothing) {
+            ImeEvent::Disabled
+        } else {
+            ImeEvent::Enabled
+        };
+        self.ime_events.push_back((window, event));
+
+        Ok(())
+    }
+
+    fn handle_destroy_ic(
+        &mut self,
+        _client: &mut C,
+        _input_method_id: u16,
+        _input_context_id: u16,
+    ) -> Result<(), ClientError> {
+        // This is already handled by the higher-level function.
+        Ok(())
+    }
+
+    fn handle_set_ic_values(
+        &mut self,
+        _client: &mut C,
+        input_method_id: u16,
+        input_context_id: u16,
+    ) -> Result<(), ClientError> {
+        debug_assert_eq!(self.input_method, Some(input_method_id));
+
+        // Get the IC data.
+        let ic_data = self
+            .input_contexts
+            .get_mut(&input_context_id)
+            .ok_or_else(|| invalid_state(InvalidImeState::InvalidIc(input_context_id)))?;
+
+        // Move up the new spot
+        if let Some(spot) = ic_data.new_spot.take() {
+            ic_data.window.spot = spot;
+        }
+
+        Ok(())
+    }
+
+    fn handle_preedit_start(
+        &mut self,
+        _client: &mut C,
+        input_method_id: u16,
+        input_context_id: u16,
+    ) -> Result<(), ClientError> {
+        debug_assert_eq!(self.input_method, Some(input_method_id));
+
+        if let Some(ic_data) = self.input_contexts.get_mut(&input_context_id) {
+            // Start a pre-edit.
+            ic_data.text.clear();
+            ic_data.cursor = 0;
+
+            // Indicate the start.
+            self.ime_events
+                .push_back((ic_data.window.id, ImeEvent::Start));
+        }
+
+        Ok(())
+    }
+
+    fn handle_preedit_draw(
+        &mut self,
+        _client: &mut C,
+        input_method_id: u16,
+        input_context_id: u16,
+        caret: i32,
+        chg_first: i32,
+        chg_len: i32,
+        _status: xim::PreeditDrawStatus,
+        preedit_string: &str,
+        _feedbacks: Vec<xim::Feedback>,
+    ) -> Result<(), ClientError> {
+        debug_assert_eq!(self.input_method, Some(input_method_id));
+
+        if let Some(ic_data) = self.input_contexts.get_mut(&input_context_id) {
+            // Set the cursor.
+            ic_data.cursor = caret as usize;
+
+            // Figure out the range of text to change.
+            let change_range = chg_first as usize..(chg_first + chg_len) as usize;
+
+            // If the range doesn't fit our current text, warn and return.
+            if change_range.start > ic_data.text.len() || change_range.end > ic_data.text.len() {
+                warn!(
+                    "Preedit draw range {}..{} doesn't fit text of length {}",
+                    change_range.start,
+                    change_range.end,
+                    ic_data.text.len()
+                );
+                return Ok(());
+            }
+
+            // Update the text in the changed range.
+            {
+                let text = &mut ic_data.text;
+                let mut old_text_tail = text.split_off(change_range.end);
+
+                text.truncate(change_range.start);
+                text.extend(preedit_string.chars());
+                text.append(&mut old_text_tail);
+            }
+
+            // Send the event.
+            let cursor_byte_pos = calc_byte_position(&ic_data.text, ic_data.cursor);
+            let event = ImeEvent::Update(ic_data.text.iter().collect(), Some(cursor_byte_pos));
+
+            self.ime_events.push_back((ic_data.window.id, event));
+        }
+
+        Ok(())
+    }
+
+    fn handle_preedit_caret(
+        &mut self,
+        _client: &mut C,
+        input_method_id: u16,
+        input_context_id: u16,
+        position: &mut i32,
+        direction: xim::CaretDirection,
+        _style: xim::CaretStyle,
+    ) -> Result<(), ClientError> {
+        // We only care about absolute position.
+        if matches!(direction, xim::CaretDirection::AbsolutePosition) {
+            debug_assert_eq!(self.input_method, Some(input_method_id));
+
+            if let Some(ic_data) = self.input_contexts.get_mut(&input_context_id) {
+                ic_data.cursor = *position as usize;
+
+                // Send the event
+                let event =
+                    ImeEvent::Update(ic_data.text.iter().collect(), Some(*position as usize));
+                self.ime_events.push_back((ic_data.window.id, event));
+            }
+        }
+
+        Ok(())
+    }
+
+    fn handle_preedit_done(
+        &mut self,
+        _client: &mut C,
+        input_method_id: u16,
+        input_context_id: u16,
+    ) -> Result<(), ClientError> {
+        debug_assert_eq!(self.input_method, Some(input_method_id));
+
+        // Get the client data.
+        if let Some(ic_data) = self.input_contexts.get_mut(&input_context_id) {
+            // We're done with a preedit.
+            ic_data.text.clear();
+            ic_data.cursor = 0;
+
+            // Send a message to the window.
+            let window = ic_data.window.id;
+            self.ime_events.push_back((window, ImeEvent::End));
+        }
+
+        Ok(())
+    }
+
+    fn handle_commit(
+        &mut self,
+        _client: &mut C,
+        input_method_id: u16,
+        input_context_id: u16,
+        text: &str,
+    ) -> Result<(), ClientError> {
+        debug_assert_eq!(self.input_method, Some(input_method_id));
+
+        // Get the client data.
+        if let Some(ic_data) = self.input_contexts.get_mut(&input_context_id) {
+            // Send a message to the window.
+            let window = ic_data.window.id;
+            self.ime_events
+                .push_back((window, ImeEvent::Commit(text.to_owned())));
+        }
+
+        Ok(())
+    }
+
+    fn handle_query_extension(
+        &mut self,
+        _client: &mut C,
+        _extensions: &[xim::Extension],
+    ) -> Result<(), ClientError> {
+        // Don't care.
+        Ok(())
+    }
+
+    fn handle_forward_event(
+        &mut self,
+        _client: &mut C,
+        _input_method_id: u16,
+        _input_context_id: u16,
+        _flag: xim::ForwardEventFlag,
+        _xev: C::XEvent,
+    ) -> Result<(), ClientError> {
+        // Don't care.
+        Ok(())
+    }
+
+    fn handle_set_event_mask(
+        &mut self,
+        _client: &mut C,
+        _input_method_id: u16,
+        _input_context_id: u16,
+        _forward_event_mask: u32,
+        _synchronous_event_mask: u32,
+    ) -> Result<(), ClientError> {
+        // Don't care.
+        Ok(())
+    }
+}
+
+#[inline(always)]
+fn invalid_state(state: InvalidImeState) -> ClientError {
+    ClientError::Other(Box::new(X11Error::InvalidImeState(state)))
+}
+
+struct ImData(Option<&'static str>);
+
+impl fmt::Debug for ImData {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self.0 {
+            Some(name) => write!(f, "\"{}\"", name),
+            None => write!(f, "default input method"),
+        }
+    }
+}
+
+/// Get the current locale.
+fn locale() -> String {
+    use std::ffi::CStr;
+
+    const EN_US: &str = "en_US.UTF-8";
+
+    // Get the pointer to the current locale.
+    let locale_ptr = unsafe { libc::setlocale(libc::LC_CTYPE, std::ptr::null()) };
+
+    // If locale_ptr is null, just default to en_US.UTF-8.
+    if locale_ptr.is_null() {
+        return EN_US.to_owned();
+    }
+
+    // Convert the pointer to a CStr.
+    let locale_cstr = unsafe { CStr::from_ptr(locale_ptr) };
+
+    // Convert the CStr to a String to prevent the result from getting clobbered.
+    locale_cstr.to_str().unwrap_or(EN_US).to_owned()
+}
+
+fn calc_byte_position(text: &[char], pos: usize) -> usize {
+    text.iter().take(pos).map(|c| c.len_utf8()).sum()
+}

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

@@ -1,215 +0,0 @@
-use std::{collections::HashMap, os::raw::c_char, ptr, sync::Arc};
-
-use super::{ffi, XConnection, XError};
-
-use super::{
-    context::{ImeContext, ImeContextCreationError},
-    inner::{close_im, ImeInner},
-    input_method::PotentialInputMethods,
-};
-
-pub(crate) unsafe fn xim_set_callback(
-    xconn: &Arc<XConnection>,
-    xim: ffi::XIM,
-    field: *const c_char,
-    callback: *mut ffi::XIMCallback,
-) -> Result<(), XError> {
-    // It's advisable to wrap variadic FFI functions in our own functions, as we want to minimize
-    // access that isn't type-checked.
-    unsafe { (xconn.xlib.XSetIMValues)(xim, field, callback, ptr::null_mut::<()>()) };
-    xconn.check_errors()
-}
-
-// Set a callback for when an input method matching the current locale modifiers becomes
-// available. Note that this has nothing to do with what input methods are open or able to be
-// opened, and simply uses the modifiers that are set when the callback is set.
-// * This is called per locale modifier, not per input method opened with that locale modifier.
-// * Trying to set this for multiple locale modifiers causes problems, i.e. one of the rebuilt
-//   input contexts would always silently fail to use the input method.
-pub(crate) unsafe fn set_instantiate_callback(
-    xconn: &Arc<XConnection>,
-    client_data: ffi::XPointer,
-) -> Result<(), XError> {
-    unsafe {
-        (xconn.xlib.XRegisterIMInstantiateCallback)(
-            xconn.display,
-            ptr::null_mut(),
-            ptr::null_mut(),
-            ptr::null_mut(),
-            Some(xim_instantiate_callback),
-            client_data,
-        )
-    };
-    xconn.check_errors()
-}
-
-pub(crate) unsafe fn unset_instantiate_callback(
-    xconn: &Arc<XConnection>,
-    client_data: ffi::XPointer,
-) -> Result<(), XError> {
-    unsafe {
-        (xconn.xlib.XUnregisterIMInstantiateCallback)(
-            xconn.display,
-            ptr::null_mut(),
-            ptr::null_mut(),
-            ptr::null_mut(),
-            Some(xim_instantiate_callback),
-            client_data,
-        )
-    };
-    xconn.check_errors()
-}
-
-pub(crate) unsafe fn set_destroy_callback(
-    xconn: &Arc<XConnection>,
-    im: ffi::XIM,
-    inner: &ImeInner,
-) -> Result<(), XError> {
-    unsafe {
-        xim_set_callback(
-            xconn,
-            im,
-            ffi::XNDestroyCallback_0.as_ptr() as *const _,
-            &inner.destroy_callback as *const _ as *mut _,
-        )
-    }
-}
-
-#[derive(Debug)]
-#[allow(clippy::enum_variant_names)]
-enum ReplaceImError {
-    // Boxed to prevent large error type
-    MethodOpenFailed(Box<PotentialInputMethods>),
-    ContextCreationFailed(ImeContextCreationError),
-    SetDestroyCallbackFailed(XError),
-}
-
-// Attempt to replace current IM (which may or may not be presently valid) with a new one. This
-// includes replacing all existing input contexts and free'ing resources as necessary. This only
-// modifies existing state if all operations succeed.
-unsafe fn replace_im(inner: *mut ImeInner) -> Result<(), ReplaceImError> {
-    let xconn = unsafe { &(*inner).xconn };
-
-    let (new_im, is_fallback) = {
-        let new_im = unsafe { (*inner).potential_input_methods.open_im(xconn, None) };
-        let is_fallback = new_im.is_fallback();
-        (
-            new_im.ok().ok_or_else(|| {
-                ReplaceImError::MethodOpenFailed(Box::new(unsafe {
-                    (*inner).potential_input_methods.clone()
-                }))
-            })?,
-            is_fallback,
-        )
-    };
-
-    // It's important to always set a destroy callback, since there's otherwise potential for us
-    // to try to use or free a resource that's already been destroyed on the server.
-    {
-        let result = unsafe { set_destroy_callback(xconn, new_im.im, &*inner) };
-        if result.is_err() {
-            let _ = unsafe { close_im(xconn, new_im.im) };
-        }
-        result
-    }
-    .map_err(ReplaceImError::SetDestroyCallbackFailed)?;
-
-    let mut new_contexts = HashMap::new();
-    for (window, old_context) in unsafe { (*inner).contexts.iter() } {
-        let spot = old_context.as_ref().map(|old_context| old_context.ic_spot);
-
-        // Check if the IME was allowed on that context.
-        let is_allowed = old_context
-            .as_ref()
-            .map(|old_context| old_context.is_allowed())
-            .unwrap_or_default();
-
-        // We can't use the style from the old context here, since it may change on reload, so
-        // pick style from the new XIM based on the old state.
-        let style = if is_allowed {
-            new_im.preedit_style
-        } else {
-            new_im.none_style
-        };
-
-        let new_context = {
-            let result = unsafe {
-                ImeContext::new(
-                    xconn,
-                    new_im.im,
-                    style,
-                    *window,
-                    spot,
-                    (*inner).event_sender.clone(),
-                )
-            };
-            if result.is_err() {
-                let _ = unsafe { close_im(xconn, new_im.im) };
-            }
-            result.map_err(ReplaceImError::ContextCreationFailed)?
-        };
-        new_contexts.insert(*window, Some(new_context));
-    }
-
-    // If we've made it this far, everything succeeded.
-    unsafe {
-        let _ = (*inner).destroy_all_contexts_if_necessary();
-        let _ = (*inner).close_im_if_necessary();
-        (*inner).im = Some(new_im);
-        (*inner).contexts = new_contexts;
-        (*inner).is_destroyed = false;
-        (*inner).is_fallback = is_fallback;
-    }
-    Ok(())
-}
-
-pub unsafe extern "C" fn xim_instantiate_callback(
-    _display: *mut ffi::Display,
-    client_data: ffi::XPointer,
-    // This field is unsupplied.
-    _call_data: ffi::XPointer,
-) {
-    let inner: *mut ImeInner = client_data as _;
-    if !inner.is_null() {
-        let xconn = unsafe { &(*inner).xconn };
-        match unsafe { replace_im(inner) } {
-            Ok(()) => unsafe {
-                let _ = unset_instantiate_callback(xconn, client_data);
-                (*inner).is_fallback = false;
-            },
-            Err(err) => unsafe {
-                if (*inner).is_destroyed {
-                    // We have no usable input methods!
-                    panic!("Failed to reopen input method: {err:?}");
-                }
-            },
-        }
-    }
-}
-
-// This callback is triggered when the input method is closed on the server end. When this
-// happens, XCloseIM/XDestroyIC doesn't need to be called, as the resources have already been
-// free'd (attempting to do so causes our connection to freeze).
-pub unsafe extern "C" fn xim_destroy_callback(
-    _xim: ffi::XIM,
-    client_data: ffi::XPointer,
-    // This field is unsupplied.
-    _call_data: ffi::XPointer,
-) {
-    let inner: *mut ImeInner = client_data as _;
-    if !inner.is_null() {
-        unsafe { (*inner).is_destroyed = true };
-        let xconn = unsafe { &(*inner).xconn };
-        if unsafe { !(*inner).is_fallback } {
-            let _ = unsafe { set_instantiate_callback(xconn, client_data) };
-            // Attempt to open fallback input method.
-            match unsafe { replace_im(inner) } {
-                Ok(()) => unsafe { (*inner).is_fallback = true },
-                Err(err) => {
-                    // We have no usable input methods!
-                    panic!("Failed to open fallback input method: {err:?}");
-                }
-            }
-        }
-    }
-}

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

@@ -1,385 +0,0 @@
-use std::ffi::CStr;
-use std::os::raw::c_short;
-use std::sync::Arc;
-use std::{mem, ptr};
-
-use x11_dl::xlib::{XIMCallback, XIMPreeditCaretCallbackStruct, XIMPreeditDrawCallbackStruct};
-
-use crate::platform_impl::platform::x11::ime::input_method::{Style, XIMStyle};
-use crate::platform_impl::platform::x11::ime::{ImeEvent, ImeEventSender};
-
-use super::{ffi, util, XConnection, XError};
-
-/// IME creation error.
-#[derive(Debug)]
-pub enum ImeContextCreationError {
-    /// Got the error from Xlib.
-    XError(XError),
-
-    /// Got null pointer from Xlib but without exact reason.
-    Null,
-}
-
-/// The callback used by XIM preedit functions.
-type XIMProcNonnull = unsafe extern "C" fn(ffi::XIM, ffi::XPointer, ffi::XPointer);
-
-/// Wrapper for creating XIM callbacks.
-#[inline]
-fn create_xim_callback(client_data: ffi::XPointer, callback: XIMProcNonnull) -> ffi::XIMCallback {
-    XIMCallback {
-        client_data,
-        callback: Some(callback),
-    }
-}
-
-/// The server started preedit.
-extern "C" fn preedit_start_callback(
-    _xim: ffi::XIM,
-    client_data: ffi::XPointer,
-    _call_data: ffi::XPointer,
-) -> i32 {
-    let client_data = unsafe { &mut *(client_data as *mut ImeContextClientData) };
-
-    client_data.text.clear();
-    client_data.cursor_pos = 0;
-    client_data
-        .event_sender
-        .send((client_data.window, ImeEvent::Start))
-        .expect("failed to send preedit start event");
-    -1
-}
-
-/// Done callback is used when the preedit should be hidden.
-extern "C" fn preedit_done_callback(
-    _xim: ffi::XIM,
-    client_data: ffi::XPointer,
-    _call_data: ffi::XPointer,
-) {
-    let client_data = unsafe { &mut *(client_data as *mut ImeContextClientData) };
-
-    // Drop text buffer and reset cursor position on done.
-    client_data.text = Vec::new();
-    client_data.cursor_pos = 0;
-
-    client_data
-        .event_sender
-        .send((client_data.window, ImeEvent::End))
-        .expect("failed to send preedit end event");
-}
-
-fn calc_byte_position(text: &[char], pos: usize) -> usize {
-    text.iter()
-        .take(pos)
-        .fold(0, |byte_pos, text| byte_pos + text.len_utf8())
-}
-
-/// Preedit text information to be drawn inline by the client.
-extern "C" fn preedit_draw_callback(
-    _xim: ffi::XIM,
-    client_data: ffi::XPointer,
-    call_data: ffi::XPointer,
-) {
-    let client_data = unsafe { &mut *(client_data as *mut ImeContextClientData) };
-    let call_data = unsafe { &mut *(call_data as *mut XIMPreeditDrawCallbackStruct) };
-    client_data.cursor_pos = call_data.caret as usize;
-
-    let chg_range =
-        call_data.chg_first as usize..(call_data.chg_first + call_data.chg_length) as usize;
-    if chg_range.start > client_data.text.len() || chg_range.end > client_data.text.len() {
-        warn!(
-            "invalid chg range: buffer length={}, but chg_first={} chg_lengthg={}",
-            client_data.text.len(),
-            call_data.chg_first,
-            call_data.chg_length
-        );
-        return;
-    }
-
-    // NULL indicate text deletion
-    let mut new_chars = if call_data.text.is_null() {
-        Vec::new()
-    } else {
-        let xim_text = unsafe { &mut *(call_data.text) };
-        if xim_text.encoding_is_wchar > 0 {
-            return;
-        }
-
-        let new_text = unsafe { xim_text.string.multi_byte };
-
-        if new_text.is_null() {
-            return;
-        }
-
-        let new_text = unsafe { CStr::from_ptr(new_text) };
-
-        String::from(new_text.to_str().expect("Invalid UTF-8 String from IME"))
-            .chars()
-            .collect()
-    };
-    let mut old_text_tail = client_data.text.split_off(chg_range.end);
-    client_data.text.truncate(chg_range.start);
-    client_data.text.append(&mut new_chars);
-    client_data.text.append(&mut old_text_tail);
-    let cursor_byte_pos = calc_byte_position(&client_data.text, client_data.cursor_pos);
-
-    client_data
-        .event_sender
-        .send((
-            client_data.window,
-            ImeEvent::Update(client_data.text.iter().collect(), cursor_byte_pos),
-        ))
-        .expect("failed to send preedit update event");
-}
-
-/// Handling of cursor movements in preedit text.
-extern "C" fn preedit_caret_callback(
-    _xim: ffi::XIM,
-    client_data: ffi::XPointer,
-    call_data: ffi::XPointer,
-) {
-    let client_data = unsafe { &mut *(client_data as *mut ImeContextClientData) };
-    let call_data = unsafe { &mut *(call_data as *mut XIMPreeditCaretCallbackStruct) };
-
-    if call_data.direction == ffi::XIMCaretDirection::XIMAbsolutePosition {
-        client_data.cursor_pos = call_data.position as usize;
-        let cursor_byte_pos = calc_byte_position(&client_data.text, client_data.cursor_pos);
-
-        client_data
-            .event_sender
-            .send((
-                client_data.window,
-                ImeEvent::Update(client_data.text.iter().collect(), cursor_byte_pos),
-            ))
-            .expect("failed to send preedit update event");
-    }
-}
-
-/// Struct to simplify callback creation and latter passing into Xlib XIM.
-struct PreeditCallbacks {
-    start_callback: ffi::XIMCallback,
-    done_callback: ffi::XIMCallback,
-    draw_callback: ffi::XIMCallback,
-    caret_callback: ffi::XIMCallback,
-}
-
-impl PreeditCallbacks {
-    pub fn new(client_data: ffi::XPointer) -> PreeditCallbacks {
-        let start_callback = create_xim_callback(client_data, unsafe {
-            mem::transmute(preedit_start_callback as usize)
-        });
-        let done_callback = create_xim_callback(client_data, preedit_done_callback);
-        let caret_callback = create_xim_callback(client_data, preedit_caret_callback);
-        let draw_callback = create_xim_callback(client_data, preedit_draw_callback);
-
-        PreeditCallbacks {
-            start_callback,
-            done_callback,
-            caret_callback,
-            draw_callback,
-        }
-    }
-}
-
-struct ImeContextClientData {
-    window: ffi::Window,
-    event_sender: ImeEventSender,
-    text: Vec<char>,
-    cursor_pos: usize,
-}
-
-// XXX: this struct doesn't destroy its XIC resource when dropped.
-// This is intentional, as it doesn't have enough information to know whether or not the context
-// still exists on the server. Since `ImeInner` has that awareness, destruction must be handled
-// through `ImeInner`.
-pub struct ImeContext {
-    pub(crate) ic: ffi::XIC,
-    pub(crate) ic_spot: ffi::XPoint,
-    pub(crate) style: Style,
-    // Since the data is passed shared between X11 XIM callbacks, but couldn't be direclty free from
-    // there we keep the pointer to automatically deallocate it.
-    _client_data: Box<ImeContextClientData>,
-}
-
-impl ImeContext {
-    pub(crate) unsafe fn new(
-        xconn: &Arc<XConnection>,
-        im: ffi::XIM,
-        style: Style,
-        window: ffi::Window,
-        ic_spot: Option<ffi::XPoint>,
-        event_sender: ImeEventSender,
-    ) -> Result<Self, ImeContextCreationError> {
-        let client_data = Box::into_raw(Box::new(ImeContextClientData {
-            window,
-            event_sender,
-            text: Vec::new(),
-            cursor_pos: 0,
-        }));
-
-        let ic = match style as _ {
-            Style::Preedit(style) => unsafe {
-                ImeContext::create_preedit_ic(
-                    xconn,
-                    im,
-                    style,
-                    window,
-                    client_data as ffi::XPointer,
-                )
-            },
-            Style::Nothing(style) => unsafe {
-                ImeContext::create_nothing_ic(xconn, im, style, window)
-            },
-            Style::None(style) => unsafe { ImeContext::create_none_ic(xconn, im, style, window) },
-        }
-        .ok_or(ImeContextCreationError::Null)?;
-
-        xconn
-            .check_errors()
-            .map_err(ImeContextCreationError::XError)?;
-
-        let mut context = ImeContext {
-            ic,
-            ic_spot: ffi::XPoint { x: 0, y: 0 },
-            style,
-            _client_data: unsafe { Box::from_raw(client_data) },
-        };
-
-        // Set the spot location, if it's present.
-        if let Some(ic_spot) = ic_spot {
-            context.set_spot(xconn, ic_spot.x, ic_spot.y)
-        }
-
-        Ok(context)
-    }
-
-    unsafe fn create_none_ic(
-        xconn: &Arc<XConnection>,
-        im: ffi::XIM,
-        style: XIMStyle,
-        window: ffi::Window,
-    ) -> Option<ffi::XIC> {
-        let ic = unsafe {
-            (xconn.xlib.XCreateIC)(
-                im,
-                ffi::XNInputStyle_0.as_ptr() as *const _,
-                style,
-                ffi::XNClientWindow_0.as_ptr() as *const _,
-                window,
-                ptr::null_mut::<()>(),
-            )
-        };
-
-        (!ic.is_null()).then_some(ic)
-    }
-
-    unsafe fn create_preedit_ic(
-        xconn: &Arc<XConnection>,
-        im: ffi::XIM,
-        style: XIMStyle,
-        window: ffi::Window,
-        client_data: ffi::XPointer,
-    ) -> Option<ffi::XIC> {
-        let preedit_callbacks = PreeditCallbacks::new(client_data);
-        let preedit_attr = util::memory::XSmartPointer::new(xconn, unsafe {
-            (xconn.xlib.XVaCreateNestedList)(
-                0,
-                ffi::XNPreeditStartCallback_0.as_ptr() as *const _,
-                &(preedit_callbacks.start_callback) as *const _,
-                ffi::XNPreeditDoneCallback_0.as_ptr() as *const _,
-                &(preedit_callbacks.done_callback) as *const _,
-                ffi::XNPreeditCaretCallback_0.as_ptr() as *const _,
-                &(preedit_callbacks.caret_callback) as *const _,
-                ffi::XNPreeditDrawCallback_0.as_ptr() as *const _,
-                &(preedit_callbacks.draw_callback) as *const _,
-                ptr::null_mut::<()>(),
-            )
-        })
-        .expect("XVaCreateNestedList returned NULL");
-
-        let ic = unsafe {
-            (xconn.xlib.XCreateIC)(
-                im,
-                ffi::XNInputStyle_0.as_ptr() as *const _,
-                style,
-                ffi::XNClientWindow_0.as_ptr() as *const _,
-                window,
-                ffi::XNPreeditAttributes_0.as_ptr() as *const _,
-                preedit_attr.ptr,
-                ptr::null_mut::<()>(),
-            )
-        };
-
-        (!ic.is_null()).then_some(ic)
-    }
-
-    unsafe fn create_nothing_ic(
-        xconn: &Arc<XConnection>,
-        im: ffi::XIM,
-        style: XIMStyle,
-        window: ffi::Window,
-    ) -> Option<ffi::XIC> {
-        let ic = unsafe {
-            (xconn.xlib.XCreateIC)(
-                im,
-                ffi::XNInputStyle_0.as_ptr() as *const _,
-                style,
-                ffi::XNClientWindow_0.as_ptr() as *const _,
-                window,
-                ptr::null_mut::<()>(),
-            )
-        };
-
-        (!ic.is_null()).then_some(ic)
-    }
-
-    pub(crate) fn focus(&self, xconn: &Arc<XConnection>) -> Result<(), XError> {
-        unsafe {
-            (xconn.xlib.XSetICFocus)(self.ic);
-        }
-        xconn.check_errors()
-    }
-
-    pub(crate) fn unfocus(&self, xconn: &Arc<XConnection>) -> Result<(), XError> {
-        unsafe {
-            (xconn.xlib.XUnsetICFocus)(self.ic);
-        }
-        xconn.check_errors()
-    }
-
-    pub fn is_allowed(&self) -> bool {
-        !matches!(self.style, Style::None(_))
-    }
-
-    // Set the spot for preedit text. Setting spot isn't working with libX11 when preedit callbacks
-    // are being used. Certain IMEs do show selection window, but it's placed in bottom left of the
-    // window and couldn't be changed.
-    //
-    // For me see: https://bugs.freedesktop.org/show_bug.cgi?id=1580.
-    pub(crate) fn set_spot(&mut self, xconn: &Arc<XConnection>, x: c_short, y: c_short) {
-        if !self.is_allowed() || self.ic_spot.x == x && self.ic_spot.y == y {
-            return;
-        }
-
-        self.ic_spot = ffi::XPoint { x, y };
-
-        unsafe {
-            let preedit_attr = util::memory::XSmartPointer::new(
-                xconn,
-                (xconn.xlib.XVaCreateNestedList)(
-                    0,
-                    ffi::XNSpotLocation_0.as_ptr(),
-                    &self.ic_spot,
-                    ptr::null_mut::<()>(),
-                ),
-            )
-            .expect("XVaCreateNestedList returned NULL");
-
-            (xconn.xlib.XSetICValues)(
-                self.ic,
-                ffi::XNPreeditAttributes_0.as_ptr() as *const _,
-                preedit_attr.ptr,
-                ptr::null_mut::<()>(),
-            );
-        }
-    }
-}

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

@@ -1,75 +0,0 @@
-use std::{collections::HashMap, mem, sync::Arc};
-
-use super::{ffi, XConnection, XError};
-
-use super::{
-    context::ImeContext,
-    input_method::{InputMethod, PotentialInputMethods},
-};
-use crate::platform_impl::platform::x11::ime::ImeEventSender;
-
-pub(crate) unsafe fn close_im(xconn: &Arc<XConnection>, im: ffi::XIM) -> Result<(), XError> {
-    unsafe { (xconn.xlib.XCloseIM)(im) };
-    xconn.check_errors()
-}
-
-pub(crate) unsafe fn destroy_ic(xconn: &Arc<XConnection>, ic: ffi::XIC) -> Result<(), XError> {
-    unsafe { (xconn.xlib.XDestroyIC)(ic) };
-    xconn.check_errors()
-}
-
-pub(crate) struct ImeInner {
-    pub xconn: Arc<XConnection>,
-    pub im: Option<InputMethod>,
-    pub potential_input_methods: PotentialInputMethods,
-    pub contexts: HashMap<ffi::Window, Option<ImeContext>>,
-    // WARNING: this is initially zeroed!
-    pub destroy_callback: ffi::XIMCallback,
-    pub event_sender: ImeEventSender,
-    // Indicates whether or not the the input method was destroyed on the server end
-    // (i.e. if ibus/fcitx/etc. was terminated/restarted)
-    pub is_destroyed: bool,
-    pub is_fallback: bool,
-}
-
-impl ImeInner {
-    pub(crate) fn new(
-        xconn: Arc<XConnection>,
-        potential_input_methods: PotentialInputMethods,
-        event_sender: ImeEventSender,
-    ) -> Self {
-        ImeInner {
-            xconn,
-            im: None,
-            potential_input_methods,
-            contexts: HashMap::new(),
-            destroy_callback: unsafe { mem::zeroed() },
-            event_sender,
-            is_destroyed: false,
-            is_fallback: false,
-        }
-    }
-
-    pub unsafe fn close_im_if_necessary(&self) -> Result<bool, XError> {
-        if !self.is_destroyed && self.im.is_some() {
-            unsafe { close_im(&self.xconn, self.im.as_ref().unwrap().im) }.map(|_| true)
-        } else {
-            Ok(false)
-        }
-    }
-
-    pub unsafe fn destroy_ic_if_necessary(&self, ic: ffi::XIC) -> Result<bool, XError> {
-        if !self.is_destroyed {
-            unsafe { destroy_ic(&self.xconn, ic) }.map(|_| true)
-        } else {
-            Ok(false)
-        }
-    }
-
-    pub unsafe fn destroy_all_contexts_if_necessary(&self) -> Result<bool, XError> {
-        for context in self.contexts.values().flatten() {
-            unsafe { self.destroy_ic_if_necessary(context.ic)? };
-        }
-        Ok(!self.is_destroyed)
-    }
-}

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

@@ -1,370 +0,0 @@
-use std::{
-    env,
-    ffi::{CStr, CString, IntoStringError},
-    fmt,
-    os::raw::{c_char, c_ulong, c_ushort},
-    ptr,
-    sync::{Arc, Mutex},
-};
-
-use super::{super::atoms::*, ffi, util, XConnection, XError};
-use once_cell::sync::Lazy;
-use x11rb::protocol::xproto;
-
-static GLOBAL_LOCK: Lazy<Mutex<()>> = Lazy::new(Default::default);
-
-unsafe fn open_im(xconn: &Arc<XConnection>, locale_modifiers: &CStr) -> Option<ffi::XIM> {
-    let _lock = GLOBAL_LOCK.lock();
-
-    // 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 or if the
-    //   current locale is not supported by Xlib.
-    unsafe { (xconn.xlib.XSetLocaleModifiers)(locale_modifiers.as_ptr()) };
-
-    let im = unsafe {
-        (xconn.xlib.XOpenIM)(
-            xconn.display,
-            ptr::null_mut(),
-            ptr::null_mut(),
-            ptr::null_mut(),
-        )
-    };
-
-    if im.is_null() {
-        None
-    } else {
-        Some(im)
-    }
-}
-
-#[derive(Debug)]
-pub struct InputMethod {
-    pub im: ffi::XIM,
-    pub preedit_style: Style,
-    pub none_style: Style,
-    _name: String,
-}
-
-impl InputMethod {
-    fn new(xconn: &Arc<XConnection>, im: ffi::XIM, name: String) -> Option<Self> {
-        let mut styles: *mut XIMStyles = std::ptr::null_mut();
-
-        // Query the styles supported by the XIM.
-        unsafe {
-            if !(xconn.xlib.XGetIMValues)(
-                im,
-                ffi::XNQueryInputStyle_0.as_ptr() as *const _,
-                (&mut styles) as *mut _,
-                std::ptr::null_mut::<()>(),
-            )
-            .is_null()
-            {
-                return None;
-            }
-        }
-
-        let mut preedit_style = None;
-        let mut none_style = None;
-
-        unsafe {
-            std::slice::from_raw_parts((*styles).supported_styles, (*styles).count_styles as _)
-                .iter()
-                .for_each(|style| match *style {
-                    XIM_PREEDIT_STYLE => {
-                        preedit_style = Some(Style::Preedit(*style));
-                    }
-                    XIM_NOTHING_STYLE if preedit_style.is_none() => {
-                        preedit_style = Some(Style::Nothing(*style))
-                    }
-                    XIM_NONE_STYLE => none_style = Some(Style::None(*style)),
-                    _ => (),
-                });
-
-            (xconn.xlib.XFree)(styles.cast());
-        };
-
-        if preedit_style.is_none() && none_style.is_none() {
-            return None;
-        }
-
-        let preedit_style = preedit_style.unwrap_or_else(|| none_style.unwrap());
-        let none_style = none_style.unwrap_or(preedit_style);
-
-        Some(InputMethod {
-            im,
-            _name: name,
-            preedit_style,
-            none_style,
-        })
-    }
-}
-
-const XIM_PREEDIT_STYLE: XIMStyle = (ffi::XIMPreeditCallbacks | ffi::XIMStatusNothing) as XIMStyle;
-const XIM_NOTHING_STYLE: XIMStyle = (ffi::XIMPreeditNothing | ffi::XIMStatusNothing) as XIMStyle;
-const XIM_NONE_STYLE: XIMStyle = (ffi::XIMPreeditNone | ffi::XIMStatusNone) as XIMStyle;
-
-/// Style of the IME context.
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-pub enum Style {
-    /// Preedit callbacks.
-    Preedit(XIMStyle),
-
-    /// Nothing.
-    Nothing(XIMStyle),
-
-    /// No IME.
-    None(XIMStyle),
-}
-
-impl Default for Style {
-    fn default() -> Self {
-        Style::None(XIM_NONE_STYLE)
-    }
-}
-
-#[repr(C)]
-#[derive(Debug)]
-struct XIMStyles {
-    count_styles: c_ushort,
-    supported_styles: *const XIMStyle,
-}
-
-pub(crate) type XIMStyle = c_ulong;
-
-#[derive(Debug)]
-pub enum InputMethodResult {
-    /// Input method used locale modifier from `XMODIFIERS` environment variable.
-    XModifiers(InputMethod),
-    /// Input method used internal fallback locale modifier.
-    Fallback(InputMethod),
-    /// Input method could not be opened using any locale modifier tried.
-    Failure,
-}
-
-impl InputMethodResult {
-    pub fn is_fallback(&self) -> bool {
-        matches!(self, InputMethodResult::Fallback(_))
-    }
-
-    pub fn ok(self) -> Option<InputMethod> {
-        use self::InputMethodResult::*;
-        match self {
-            XModifiers(im) | Fallback(im) => Some(im),
-            Failure => None,
-        }
-    }
-}
-
-#[derive(Debug, Clone)]
-enum GetXimServersError {
-    XError(XError),
-    GetPropertyError(util::GetPropertyError),
-    InvalidUtf8(IntoStringError),
-}
-
-impl From<util::GetPropertyError> for GetXimServersError {
-    fn from(error: util::GetPropertyError) -> Self {
-        GetXimServersError::GetPropertyError(error)
-    }
-}
-
-// The root window has a property named XIM_SERVERS, which contains a list of atoms represeting
-// the availabile XIM servers. For instance, if you're using ibus, it would contain an atom named
-// "@server=ibus". It's possible for this property to contain multiple atoms, though presumably
-// rare. Note that we replace "@server=" with "@im=" in order to match the format of locale
-// modifiers, since we don't want a user who's looking at logs to ask "am I supposed to set
-// XMODIFIERS to `@server=ibus`?!?"
-unsafe fn get_xim_servers(xconn: &Arc<XConnection>) -> Result<Vec<String>, GetXimServersError> {
-    let atoms = xconn.atoms();
-    let servers_atom = atoms[XIM_SERVERS];
-
-    let root = unsafe { (xconn.xlib.XDefaultRootWindow)(xconn.display) };
-
-    let mut atoms: Vec<ffi::Atom> = xconn
-        .get_property::<xproto::Atom>(
-            root as xproto::Window,
-            servers_atom,
-            xproto::Atom::from(xproto::AtomEnum::ATOM),
-        )
-        .map_err(GetXimServersError::GetPropertyError)?
-        .into_iter()
-        .map(ffi::Atom::from)
-        .collect::<Vec<_>>();
-
-    let mut names: Vec<*const c_char> = Vec::with_capacity(atoms.len());
-    unsafe {
-        (xconn.xlib.XGetAtomNames)(
-            xconn.display,
-            atoms.as_mut_ptr(),
-            atoms.len() as _,
-            names.as_mut_ptr() as _,
-        )
-    };
-    unsafe { names.set_len(atoms.len()) };
-
-    let mut formatted_names = Vec::with_capacity(names.len());
-    for name in names {
-        let string = unsafe { CStr::from_ptr(name) }
-            .to_owned()
-            .into_string()
-            .map_err(GetXimServersError::InvalidUtf8)?;
-        unsafe { (xconn.xlib.XFree)(name as _) };
-        formatted_names.push(string.replace("@server=", "@im="));
-    }
-    xconn.check_errors().map_err(GetXimServersError::XError)?;
-    Ok(formatted_names)
-}
-
-#[derive(Clone)]
-struct InputMethodName {
-    c_string: CString,
-    string: String,
-}
-
-impl InputMethodName {
-    pub fn from_string(string: String) -> Self {
-        let c_string = CString::new(string.clone())
-            .expect("String used to construct CString contained null byte");
-        InputMethodName { c_string, string }
-    }
-
-    pub fn from_str(string: &str) -> Self {
-        let c_string =
-            CString::new(string).expect("String used to construct CString contained null byte");
-        InputMethodName {
-            c_string,
-            string: string.to_owned(),
-        }
-    }
-}
-
-impl fmt::Debug for InputMethodName {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        self.string.fmt(f)
-    }
-}
-
-#[derive(Debug, Clone)]
-struct PotentialInputMethod {
-    name: InputMethodName,
-    successful: Option<bool>,
-}
-
-impl PotentialInputMethod {
-    pub fn from_string(string: String) -> Self {
-        PotentialInputMethod {
-            name: InputMethodName::from_string(string),
-            successful: None,
-        }
-    }
-
-    pub fn from_str(string: &str) -> Self {
-        PotentialInputMethod {
-            name: InputMethodName::from_str(string),
-            successful: None,
-        }
-    }
-
-    pub fn reset(&mut self) {
-        self.successful = None;
-    }
-
-    pub fn open_im(&mut self, xconn: &Arc<XConnection>) -> Option<InputMethod> {
-        let im = unsafe { open_im(xconn, &self.name.c_string) };
-        self.successful = Some(im.is_some());
-        im.and_then(|im| InputMethod::new(xconn, im, self.name.string.clone()))
-    }
-}
-
-// By logging this struct, you get a sequential listing of every locale modifier tried, where it
-// came from, and if it succeeded.
-#[derive(Debug, Clone)]
-pub(crate) struct PotentialInputMethods {
-    // On correctly configured systems, the XMODIFIERS environment variable tells us everything we
-    // need to know.
-    xmodifiers: Option<PotentialInputMethod>,
-    // We have some standard options at our disposal that should ostensibly always work. For users
-    // who only need compose sequences, this ensures that the program launches without a hitch
-    // For users who need more sophisticated IME features, this is more or less a silent failure.
-    // Logging features should be added in the future to allow both audiences to be effectively
-    // served.
-    fallbacks: [PotentialInputMethod; 2],
-    // For diagnostic purposes, we include the list of XIM servers that the server reports as
-    // being available.
-    _xim_servers: Result<Vec<String>, GetXimServersError>,
-}
-
-impl PotentialInputMethods {
-    pub fn new(xconn: &Arc<XConnection>) -> Self {
-        let xmodifiers = env::var("XMODIFIERS")
-            .ok()
-            .map(PotentialInputMethod::from_string);
-        PotentialInputMethods {
-            // Since passing "" to XSetLocaleModifiers results in it defaulting to the value of
-            // XMODIFIERS, it's worth noting what happens if XMODIFIERS is also "". If simply
-            // running the program with `XMODIFIERS="" cargo run`, then assuming XMODIFIERS is
-            // defined in the profile (or parent environment) then that parent XMODIFIERS is used.
-            // If that XMODIFIERS value is also "" (i.e. if you ran `export XMODIFIERS=""`), then
-            // XSetLocaleModifiers uses the default local input method. Note that defining
-            // XMODIFIERS as "" is different from XMODIFIERS not being defined at all, since in
-            // that case, we get `None` and end up skipping ahead to the next method.
-            xmodifiers,
-            fallbacks: [
-                // This is a standard input method that supports compose sequences, which should
-                // always be available. `@im=none` appears to mean the same thing.
-                PotentialInputMethod::from_str("@im=local"),
-                // This explicitly specifies to use the implementation-dependent default, though
-                // that seems to be equivalent to just using the local input method.
-                PotentialInputMethod::from_str("@im="),
-            ],
-            // The XIM_SERVERS property can have surprising values. For instance, when I exited
-            // ibus to run fcitx, it retained the value denoting ibus. Even more surprising is
-            // that the fcitx input method could only be successfully opened using "@im=ibus".
-            // Presumably due to this quirk, it's actually possible to alternate between ibus and
-            // fcitx in a running application.
-            _xim_servers: unsafe { get_xim_servers(xconn) },
-        }
-    }
-
-    // This resets the `successful` field of every potential input method, ensuring we have
-    // accurate information when this struct is re-used by the destruction/instantiation callbacks.
-    fn reset(&mut self) {
-        if let Some(ref mut input_method) = self.xmodifiers {
-            input_method.reset();
-        }
-
-        for input_method in &mut self.fallbacks {
-            input_method.reset();
-        }
-    }
-
-    pub fn open_im(
-        &mut self,
-        xconn: &Arc<XConnection>,
-        callback: Option<&dyn Fn()>,
-    ) -> InputMethodResult {
-        use self::InputMethodResult::*;
-
-        self.reset();
-
-        if let Some(ref mut input_method) = self.xmodifiers {
-            let im = input_method.open_im(xconn);
-            if let Some(im) = im {
-                return XModifiers(im);
-            } else if let Some(ref callback) = callback {
-                callback();
-            }
-        }
-
-        for input_method in &mut self.fallbacks {
-            let im = input_method.open_im(xconn);
-            if let Some(im) = im {
-                return Fallback(im);
-            }
-        }
-
-        Failure
-    }
-}

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

@@ -1,249 +0,0 @@
-// Important: all XIM calls need to happen from the same thread!
-
-mod callbacks;
-mod context;
-mod inner;
-mod input_method;
-
-use std::sync::{
-    mpsc::{Receiver, Sender},
-    Arc,
-};
-
-use super::{ffi, util, XConnection, XError};
-
-pub use self::context::ImeContextCreationError;
-use self::{
-    callbacks::*,
-    context::ImeContext,
-    inner::{close_im, ImeInner},
-    input_method::{PotentialInputMethods, Style},
-};
-
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
-#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-pub enum ImeEvent {
-    Enabled,
-    Start,
-    Update(String, usize),
-    End,
-    Disabled,
-}
-
-pub type ImeReceiver = Receiver<ImeRequest>;
-pub type ImeSender = Sender<ImeRequest>;
-pub type ImeEventReceiver = Receiver<(ffi::Window, ImeEvent)>;
-pub type ImeEventSender = Sender<(ffi::Window, ImeEvent)>;
-
-/// Request to control XIM handler from the window.
-pub enum ImeRequest {
-    /// Set IME spot position for given `window_id`.
-    Position(ffi::Window, i16, i16),
-
-    /// Allow IME input for the given `window_id`.
-    Allow(ffi::Window, bool),
-}
-
-#[derive(Debug)]
-pub(crate) enum ImeCreationError {
-    // Boxed to prevent large error type
-    OpenFailure(Box<PotentialInputMethods>),
-    SetDestroyCallbackFailed(XError),
-}
-
-pub(crate) struct Ime {
-    xconn: Arc<XConnection>,
-    // The actual meat of this struct is boxed away, since it needs to have a fixed location in
-    // memory so we can pass a pointer to it around.
-    inner: Box<ImeInner>,
-}
-
-impl Ime {
-    pub fn new(
-        xconn: Arc<XConnection>,
-        event_sender: ImeEventSender,
-    ) -> Result<Self, ImeCreationError> {
-        let potential_input_methods = PotentialInputMethods::new(&xconn);
-
-        let (mut inner, client_data) = {
-            let mut inner = Box::new(ImeInner::new(xconn, potential_input_methods, event_sender));
-            let inner_ptr = Box::into_raw(inner);
-            let client_data = inner_ptr as _;
-            let destroy_callback = ffi::XIMCallback {
-                client_data,
-                callback: Some(xim_destroy_callback),
-            };
-            inner = unsafe { Box::from_raw(inner_ptr) };
-            inner.destroy_callback = destroy_callback;
-            (inner, client_data)
-        };
-
-        let xconn = Arc::clone(&inner.xconn);
-
-        let input_method = inner.potential_input_methods.open_im(
-            &xconn,
-            Some(&|| {
-                let _ = unsafe { set_instantiate_callback(&xconn, client_data) };
-            }),
-        );
-
-        let is_fallback = input_method.is_fallback();
-        if let Some(input_method) = input_method.ok() {
-            inner.is_fallback = is_fallback;
-            unsafe {
-                let result = set_destroy_callback(&xconn, input_method.im, &inner)
-                    .map_err(ImeCreationError::SetDestroyCallbackFailed);
-                if result.is_err() {
-                    let _ = close_im(&xconn, input_method.im);
-                }
-                result?;
-            }
-            inner.im = Some(input_method);
-            Ok(Ime { xconn, inner })
-        } else {
-            Err(ImeCreationError::OpenFailure(Box::new(
-                inner.potential_input_methods,
-            )))
-        }
-    }
-
-    pub fn is_destroyed(&self) -> bool {
-        self.inner.is_destroyed
-    }
-
-    // This pattern is used for various methods here:
-    // Ok(_) indicates that nothing went wrong internally
-    // Ok(true) indicates that the action was actually performed
-    // Ok(false) indicates that the action is not presently applicable
-    pub fn create_context(
-        &mut self,
-        window: ffi::Window,
-        with_preedit: bool,
-    ) -> Result<bool, ImeContextCreationError> {
-        let context = if self.is_destroyed() {
-            // Create empty entry in map, so that when IME is rebuilt, this window has a context.
-            None
-        } else {
-            let im = self.inner.im.as_ref().unwrap();
-            let style = if with_preedit {
-                im.preedit_style
-            } else {
-                im.none_style
-            };
-
-            let context = unsafe {
-                ImeContext::new(
-                    &self.inner.xconn,
-                    im.im,
-                    style,
-                    window,
-                    None,
-                    self.inner.event_sender.clone(),
-                )?
-            };
-
-            // Check the state on the context, since it could fail to enable or disable preedit.
-            let event = if matches!(style, Style::None(_)) {
-                if with_preedit {
-                    debug!("failed to create IME context with preedit support.")
-                }
-                ImeEvent::Disabled
-            } else {
-                if !with_preedit {
-                    debug!("failed to create IME context without preedit support.")
-                }
-                ImeEvent::Enabled
-            };
-
-            self.inner
-                .event_sender
-                .send((window, event))
-                .expect("Failed to send enabled event");
-
-            Some(context)
-        };
-
-        self.inner.contexts.insert(window, context);
-        Ok(!self.is_destroyed())
-    }
-
-    pub fn get_context(&self, window: ffi::Window) -> Option<ffi::XIC> {
-        if self.is_destroyed() {
-            return None;
-        }
-        if let Some(Some(context)) = self.inner.contexts.get(&window) {
-            Some(context.ic)
-        } else {
-            None
-        }
-    }
-
-    pub fn remove_context(&mut self, window: ffi::Window) -> Result<bool, XError> {
-        if let Some(Some(context)) = self.inner.contexts.remove(&window) {
-            unsafe {
-                self.inner.destroy_ic_if_necessary(context.ic)?;
-            }
-            Ok(true)
-        } else {
-            Ok(false)
-        }
-    }
-
-    pub fn focus(&mut self, window: ffi::Window) -> Result<bool, XError> {
-        if self.is_destroyed() {
-            return Ok(false);
-        }
-        if let Some(&mut Some(ref mut context)) = self.inner.contexts.get_mut(&window) {
-            context.focus(&self.xconn).map(|_| true)
-        } else {
-            Ok(false)
-        }
-    }
-
-    pub fn unfocus(&mut self, window: ffi::Window) -> Result<bool, XError> {
-        if self.is_destroyed() {
-            return Ok(false);
-        }
-        if let Some(&mut Some(ref mut context)) = self.inner.contexts.get_mut(&window) {
-            context.unfocus(&self.xconn).map(|_| true)
-        } else {
-            Ok(false)
-        }
-    }
-
-    pub fn send_xim_spot(&mut self, window: ffi::Window, x: i16, y: i16) {
-        if self.is_destroyed() {
-            return;
-        }
-        if let Some(&mut Some(ref mut context)) = self.inner.contexts.get_mut(&window) {
-            context.set_spot(&self.xconn, x as _, y as _);
-        }
-    }
-
-    pub fn set_ime_allowed(&mut self, window: ffi::Window, allowed: bool) {
-        if self.is_destroyed() {
-            return;
-        }
-
-        if let Some(&mut Some(ref mut context)) = self.inner.contexts.get_mut(&window) {
-            if allowed == context.is_allowed() {
-                return;
-            }
-        }
-
-        // Remove context for that window.
-        let _ = self.remove_context(window);
-
-        // Create new context supporting IME input.
-        let _ = self.create_context(window, allowed);
-    }
-}
-
-impl Drop for Ime {
-    fn drop(&mut self) {
-        unsafe {
-            let _ = self.inner.destroy_all_contexts_if_necessary();
-            let _ = self.inner.close_im_if_necessary();
-        }
-    }
-}

src/platform_impl/linux/x11/mod.rs

@@ -28,13 +28,11 @@ use std::{
     collections::{HashMap, HashSet},
     ffi::CStr,
     fmt,
-    mem::MaybeUninit,
     ops::Deref,
     os::{
         raw::*,
         unix::io::{AsFd, AsRawFd, BorrowedFd, RawFd},
     },
-    ptr,
     rc::Rc,
     slice, str,
     sync::mpsc::{Receiver, Sender, TryRecvError},
@@ -42,19 +40,14 @@ use std::{
     time::{Duration, Instant},
 };
 
-use libc::{self, setlocale, LC_CTYPE};
-
 use atoms::*;
 
-use x11rb::x11_utils::X11Error as LogicalError;
-use x11rb::{
-    connection::RequestConnection,
-    protocol::{
-        xinput::{self, ConnectionExt as _},
-        xkb,
-        xproto::{self, ConnectionExt as _},
-    },
+use x11rb::protocol::{
+    xinput::{self, ConnectionExt as _},
+    xkb,
+    xproto::{self, ConnectionExt as _},
 };
+use x11rb::x11_utils::X11Error as LogicalError;
 use x11rb::{
     errors::{ConnectError, ConnectionError, IdsExhausted, ReplyError},
     xcb_ffi::ReplyOrIdError,
@@ -63,7 +56,6 @@ use x11rb::{
 use self::{
     dnd::{Dnd, DndState},
     event_processor::EventProcessor,
-    ime::{Ime, ImeCreationError, ImeReceiver, ImeRequest, ImeSender},
 };
 use super::{common::xkb_state::KbdState, ControlFlow, OsError};
 use crate::{
@@ -147,15 +139,18 @@ pub struct EventLoopWindowTarget<T> {
     xconn: Arc<XConnection>,
     wm_delete_window: xproto::Atom,
     net_wm_ping: xproto::Atom,
-    ime_sender: ImeSender,
+    ime_sender: mpsc::Sender<ime::ImeRequest>,
     control_flow: Cell<ControlFlow>,
     exit: Cell<Option<i32>>,
     root: xproto::Window,
-    ime: RefCell<Ime>,
     windows: RefCell<HashMap<WindowId, Weak<UnownedWindow>>>,
     redraw_sender: WakeSender<WindowId>,
     activation_sender: WakeSender<ActivationToken>,
     device_events: Cell<DeviceEvents>,
+
+    /// State of IME.
+    ime: Option<RefCell<ime::ImeData>>,
+
     _marker: ::std::marker::PhantomData<T>,
 }
 
@@ -201,57 +196,26 @@ impl<T: 'static> EventLoop<T> {
         let wm_delete_window = atoms[WM_DELETE_WINDOW];
         let net_wm_ping = atoms[_NET_WM_PING];
 
+        // Create an event queue.
+        let event_queue = Rc::new(RefCell::new(std::collections::VecDeque::with_capacity(4)));
+
         let dnd = Dnd::new(Arc::clone(&xconn))
             .expect("Failed to call XInternAtoms when initializing drag and drop");
 
         let (ime_sender, ime_receiver) = mpsc::channel();
-        let (ime_event_sender, ime_event_receiver) = mpsc::channel();
-        // 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 = match ime::ImeData::new(&xconn, xconn.default_screen_index(), &event_queue) {
+            Ok(ime) => Some(ime),
+            Err(e) => {
+                log::error!("Failed to open IME: {e}");
+                None
             }
-        }
-        let ime = RefCell::new({
-            let result = Ime::new(Arc::clone(&xconn), ime_event_sender);
-            if let Err(ImeCreationError::OpenFailure(ref state)) = result {
-                panic!("Failed to open input method: {state:#?}");
-            }
-            result.expect("Failed to set input method destruction callback")
-        });
+        };
 
-        let randr_event_offset = xconn
+        xconn
             .select_xrandr_input(root)
             .expect("Failed to query XRandR extension");
 
-        let xi2ext = xconn
-            .xcb_connection()
-            .extension_information(xinput::X11_EXTENSION_NAME)
-            .expect("Failed to query XInput extension")
-            .expect("X server missing XInput extension");
-        let xkbext = xconn
-            .xcb_connection()
-            .extension_information(xkb::X11_EXTENSION_NAME)
-            .expect("Failed to query XKB extension")
-            .expect("X server missing XKB extension");
-
         // Check for XInput2 support.
         xconn
             .xcb_connection()
@@ -303,12 +267,12 @@ impl<T: 'static> EventLoop<T> {
             KbdState::from_x11_xkb(xconn.xcb_connection().get_raw_xcb_connection()).unwrap();
 
         let window_target = EventLoopWindowTarget {
-            ime,
             root,
             control_flow: Cell::new(ControlFlow::default()),
             exit: Cell::new(None),
             windows: Default::default(),
             _marker: ::std::marker::PhantomData,
+            ime: ime.map(RefCell::new),
             ime_sender,
             xconn,
             wm_delete_window,
@@ -333,14 +297,11 @@ impl<T: 'static> EventLoop<T> {
         });
 
         let event_processor = EventProcessor {
+            event_queue,
             target: target.clone(),
             dnd,
             devices: Default::default(),
-            randr_event_offset,
-            ime_receiver,
-            ime_event_receiver,
-            xi2ext,
-            xkbext,
+            ime_requests: ime_receiver,
             kb_state,
             num_touch: 0,
             held_key_press: None,
@@ -623,12 +584,10 @@ impl<T: 'static> EventLoop<T> {
         F: FnMut(Event<T>, &RootELW<T>),
     {
         let target = &self.target;
-        let mut xev = MaybeUninit::uninit();
         let wt = get_xtarget(&self.target);
 
-        while unsafe { self.event_processor.poll_one_event(xev.as_mut_ptr()) } {
-            let mut xev = unsafe { xev.assume_init() };
-            self.event_processor.process_event(&mut xev, |event| {
+        while let Some(event) = self.event_processor.poll_one_event() {
+            self.event_processor.process_event(event, |event| {
                 if let Event::WindowEvent {
                     window_id: crate::window::WindowId(wid),
                     event: WindowEvent::RedrawRequested,
@@ -880,8 +839,11 @@ pub enum X11Error {
     /// The XID range has been exhausted.
     XidsExhausted(IdsExhausted),
 
-    /// Got `null` from an Xlib function without a reason.
-    UnexpectedNull(&'static str),
+    /// An IME client error occurred.
+    Ime(xim::ClientError),
+
+    /// The IME client has entered an invalid state.
+    InvalidImeState(ime::InvalidImeState),
 
     /// Got an invalid activation token.
     InvalidActivationToken(Vec<u8>),
@@ -900,8 +862,9 @@ impl fmt::Display for X11Error {
             X11Error::Connect(e) => write!(f, "X11 connection error: {}", e),
             X11Error::Connection(e) => write!(f, "X11 connection error: {}", e),
             X11Error::XidsExhausted(e) => write!(f, "XID range exhausted: {}", e),
+            X11Error::Ime(e) => write!(f, "An IME error occurred: {}", e),
+            X11Error::InvalidImeState(e) => write!(f, "Invalid IME state: {}", e),
             X11Error::X11(e) => write!(f, "X11 error: {:?}", e),
-            X11Error::UnexpectedNull(s) => write!(f, "Xlib function returned null: {}", s),
             X11Error::InvalidActivationToken(s) => write!(
                 f,
                 "Invalid activation token: {}",
@@ -964,15 +927,6 @@ impl From<ReplyError> for X11Error {
     }
 }
 
-impl From<ime::ImeContextCreationError> for X11Error {
-    fn from(value: ime::ImeContextCreationError) -> Self {
-        match value {
-            ime::ImeContextCreationError::XError(e) => e.into(),
-            ime::ImeContextCreationError::Null => Self::UnexpectedNull("XOpenIM"),
-        }
-    }
-}
-
 impl From<ReplyOrIdError> for X11Error {
     fn from(value: ReplyOrIdError) -> Self {
         match value {
@@ -983,6 +937,18 @@ impl From<ReplyOrIdError> for X11Error {
     }
 }
 
+impl From<xim::ClientError> for X11Error {
+    fn from(e: xim::ClientError) -> Self {
+        match e {
+            xim::ClientError::Other(other) => match other.downcast::<X11Error>() {
+                Ok(x11) => *x11,
+                Err(other) => X11Error::Ime(xim::ClientError::Other(other)),
+            },
+            e => X11Error::Ime(e),
+        }
+    }
+}
+
 /// The underlying x11rb connection that we are using.
 type X11rbConnection = x11rb::xcb_ffi::XCBConnection;
 
@@ -1001,34 +967,6 @@ impl<'a, E: fmt::Debug> CookieResultExt for Result<VoidCookie<'a>, E> {
     }
 }
 
-/// XEvents of type GenericEvent store their actual data in an XGenericEventCookie data structure. This is a wrapper to
-/// extract the cookie from a GenericEvent XEvent and release the cookie data once it has been processed
-struct GenericEventCookie<'a> {
-    xconn: &'a XConnection,
-    cookie: ffi::XGenericEventCookie,
-}
-
-impl<'a> GenericEventCookie<'a> {
-    fn from_event(xconn: &XConnection, event: ffi::XEvent) -> Option<GenericEventCookie<'_>> {
-        unsafe {
-            let mut cookie: ffi::XGenericEventCookie = From::from(event);
-            if (xconn.xlib.XGetEventData)(xconn.display, &mut cookie) == ffi::True {
-                Some(GenericEventCookie { xconn, cookie })
-            } else {
-                None
-            }
-        }
-    }
-}
-
-impl<'a> Drop for GenericEventCookie<'a> {
-    fn drop(&mut self) {
-        unsafe {
-            (self.xconn.xlib.XFreeEventData)(self.xconn.display, &mut self.cookie);
-        }
-    }
-}
-
 fn mkwid(w: xproto::Window) -> crate::window::WindowId {
     crate::window::WindowId(crate::platform_impl::platform::WindowId(w as _))
 }
@@ -1130,8 +1068,15 @@ impl Device {
     }
 }
 
-/// Convert the raw X11 representation for a 32-bit floating point to a double.
+/// Convert the raw X11 representation for a 32-bit fixed point to a double.
 #[inline]
 fn xinput_fp1616_to_float(fp: xinput::Fp1616) -> f64 {
     (fp as f64) / ((1 << 16) as f64)
 }
+
+/// Conver the raw X11 representation for a 64-bit fixed point number to a double.
+#[inline]
+fn xinput_fp3232_to_float(fp: xinput::Fp3232) -> f64 {
+    let xinput::Fp3232 { integral, frac } = fp;
+    integral as f64 + (frac as f64 / (1u64 << 32) as f64)
+}

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

@@ -1,9 +1,8 @@
-use std::ffi::CString;
-use std::iter;
+use std::{ffi::CString, iter, slice, sync::Arc};
 
 use x11rb::connection::Connection;
 
-use crate::window::CursorIcon;
+use crate::{cursor::CursorImage, window::CursorIcon};
 
 use super::*;
 
@@ -20,6 +19,11 @@ impl XConnection {
             .expect("Failed to set cursor");
     }
 
+    pub fn set_custom_cursor(&self, window: xproto::Window, cursor: &CustomCursor) {
+        self.update_cursor(window, cursor.inner.cursor)
+            .expect("Failed to set cursor");
+    }
+
     fn create_empty_cursor(&self) -> ffi::Cursor {
         let data = 0;
         let pixmap = unsafe {
@@ -87,3 +91,74 @@ impl XConnection {
         Ok(())
     }
 }
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum SelectedCursor {
+    Custom(CustomCursor),
+    Named(CursorIcon),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct CustomCursor {
+    inner: Arc<CustomCursorInner>,
+}
+
+impl CustomCursor {
+    pub(crate) unsafe fn new(xconn: &Arc<XConnection>, image: &CursorImage) -> Self {
+        unsafe {
+            let ximage =
+                (xconn.xcursor.XcursorImageCreate)(image.width as i32, image.height as i32);
+            if ximage.is_null() {
+                panic!("failed to allocate cursor image");
+            }
+            (*ximage).xhot = image.hotspot_x as u32;
+            (*ximage).yhot = image.hotspot_y as u32;
+            (*ximage).delay = 0;
+
+            let dst = slice::from_raw_parts_mut((*ximage).pixels, image.rgba.len() / 4);
+            for (dst, chunk) in dst.iter_mut().zip(image.rgba.chunks_exact(4)) {
+                *dst = (chunk[0] as u32) << 16
+                    | (chunk[1] as u32) << 8
+                    | (chunk[2] as u32)
+                    | (chunk[3] as u32) << 24;
+            }
+
+            let cursor = (xconn.xcursor.XcursorImageLoadCursor)(xconn.display, ximage);
+            (xconn.xcursor.XcursorImageDestroy)(ximage);
+            Self {
+                inner: Arc::new(CustomCursorInner {
+                    xconn: xconn.clone(),
+                    cursor,
+                }),
+            }
+        }
+    }
+}
+
+#[derive(Debug)]
+struct CustomCursorInner {
+    xconn: Arc<XConnection>,
+    cursor: ffi::Cursor,
+}
+
+impl Drop for CustomCursorInner {
+    fn drop(&mut self) {
+        unsafe {
+            (self.xconn.xlib.XFreeCursor)(self.xconn.display, self.cursor);
+        }
+    }
+}
+
+impl PartialEq for CustomCursorInner {
+    fn eq(&self, other: &Self) -> bool {
+        self.cursor == other.cursor
+    }
+}
+
+impl Eq for CustomCursorInner {}
+
+impl Default for SelectedCursor {
+    fn default() -> Self {
+        SelectedCursor::Named(Default::default())
+    }
+}

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

@@ -1,4 +1,3 @@
-use std::{slice, str};
 use x11rb::protocol::{
     xinput::{self, ConnectionExt as _},
     xkb,
@@ -9,11 +8,6 @@ use super::*;
 pub const VIRTUAL_CORE_POINTER: u16 = 2;
 pub const VIRTUAL_CORE_KEYBOARD: u16 = 3;
 
-// A base buffer size of 1kB uses a negligible amount of RAM while preventing us from having to
-// re-allocate (and make another round-trip) in the *vast* majority of cases.
-// To test if `lookup_utf8` works correctly, set this to 1.
-const TEXT_BUFFER_SIZE: usize = 1024;
-
 impl XConnection {
     pub fn select_xinput_events(
         &self,
@@ -60,52 +54,4 @@ impl XConnection {
             .reply()
             .map_err(Into::into)
     }
-
-    fn lookup_utf8_inner(
-        &self,
-        ic: ffi::XIC,
-        key_event: &mut ffi::XKeyEvent,
-        buffer: *mut u8,
-        size: usize,
-    ) -> (ffi::KeySym, ffi::Status, c_int) {
-        let mut keysym: ffi::KeySym = 0;
-        let mut status: ffi::Status = 0;
-        let count = unsafe {
-            (self.xlib.Xutf8LookupString)(
-                ic,
-                key_event,
-                buffer as *mut c_char,
-                size as c_int,
-                &mut keysym,
-                &mut status,
-            )
-        };
-        (keysym, status, count)
-    }
-
-    pub fn lookup_utf8(&self, ic: ffi::XIC, key_event: &mut ffi::XKeyEvent) -> String {
-        // `assume_init` is safe here because the array consists of `MaybeUninit` values,
-        // which do not require initialization.
-        let mut buffer: [MaybeUninit<u8>; TEXT_BUFFER_SIZE] =
-            unsafe { MaybeUninit::uninit().assume_init() };
-        // If the buffer overflows, we'll make a new one on the heap.
-        let mut vec;
-
-        let (_, status, count) =
-            self.lookup_utf8_inner(ic, key_event, buffer.as_mut_ptr() as *mut u8, buffer.len());
-
-        let bytes = if status == ffi::XBufferOverflow {
-            vec = Vec::with_capacity(count as usize);
-            let (_, _, new_count) =
-                self.lookup_utf8_inner(ic, key_event, vec.as_mut_ptr(), vec.capacity());
-            debug_assert_eq!(count, new_count);
-
-            unsafe { vec.set_len(count as usize) };
-            &vec[..count as usize]
-        } else {
-            unsafe { slice::from_raw_parts(buffer.as_ptr() as *const u8, count as usize) }
-        };
-
-        str::from_utf8(bytes).unwrap_or("").to_string()
-    }
 }

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

@@ -7,18 +7,6 @@ pub(crate) struct XSmartPointer<'a, T> {
     pub ptr: *mut T,
 }
 
-impl<'a, T> XSmartPointer<'a, T> {
-    // You're responsible for only passing things to this that should be XFree'd.
-    // Returns None if ptr is null.
-    pub fn new(xconn: &'a XConnection, ptr: *mut T) -> Option<Self> {
-        if !ptr.is_null() {
-            Some(XSmartPointer { xconn, ptr })
-        } else {
-            None
-        }
-    }
-}
-
 impl<'a, T> Deref for XSmartPointer<'a, T> {
     type Target = T;
 

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

@@ -13,11 +13,10 @@ mod randr;
 mod window_property;
 mod wm;
 
-pub use self::{geometry::*, hint::*, input::*, window_property::*, wm::*};
+pub use self::{cursor::*, geometry::*, hint::*, input::*, window_property::*, wm::*};
 
 use std::{
     mem::{self, MaybeUninit},
-    ops::BitAnd,
     os::raw::*,
 };
 
@@ -34,13 +33,6 @@ pub fn maybe_change<T: PartialEq>(field: &mut Option<T>, value: T) -> bool {
     }
 }
 
-pub fn has_flag<T>(bitset: T, flag: T) -> bool
-where
-    T: Copy + PartialEq + BitAnd<T, Output = T>,
-{
-    bitset & flag == flag
-}
-
 impl XConnection {
     // This is impoartant, so pay attention!
     // Xlib has an output buffer, and tries to hide the async nature of X from you.

src/platform_impl/linux/x11/window.rs

@@ -4,9 +4,12 @@ use std::{
     mem::replace,
     os::raw::*,
     path::Path,
-    sync::{Arc, Mutex, MutexGuard},
+    sync::{mpsc, Arc, Mutex, MutexGuard},
 };
 
+use crate::cursor::CustomCursor as RootCustomCursor;
+
+use cursor_icon::CursorIcon;
 use x11rb::{
     connection::Connection,
     properties::{WmHints, WmHintsState, WmSizeHints, WmSizeHintsSpecification},
@@ -33,14 +36,16 @@ use crate::{
         PlatformSpecificWindowBuilderAttributes, VideoMode as PlatformVideoMode,
     },
     window::{
-        CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
-        WindowAttributes, WindowButtons, WindowLevel,
+        CursorGrabMode, ImePurpose, ResizeDirection, Theme, UserAttentionType, WindowAttributes,
+        WindowButtons, WindowLevel,
     },
 };
 
 use super::{
-    ffi, util, CookieResultExt, EventLoopWindowTarget, ImeRequest, ImeSender, VoidCookie, WindowId,
-    XConnection,
+    ffi,
+    ime::ImeRequest,
+    util::{self, CustomCursor, SelectedCursor},
+    CookieResultExt, EventLoopWindowTarget, VoidCookie, WindowId, XConnection,
 };
 
 #[derive(Debug)]
@@ -126,11 +131,11 @@ pub(crate) struct UnownedWindow {
     root: xproto::Window,               // never changes
     #[allow(dead_code)]
     screen_id: i32, // never changes
-    cursor: Mutex<CursorIcon>,
+    selected_cursor: Mutex<SelectedCursor>,
     cursor_grabbed_mode: Mutex<CursorGrabMode>,
     #[allow(clippy::mutex_atomic)]
     cursor_visible: Mutex<bool>,
-    ime_sender: Mutex<ImeSender>,
+    ime_sender: Mutex<mpsc::Sender<ImeRequest>>,
     pub shared_state: Mutex<SharedState>,
     redraw_sender: WakeSender<WindowId>,
     activation_sender: WakeSender<super::ActivationToken>,
@@ -355,7 +360,7 @@ impl UnownedWindow {
             visual,
             root,
             screen_id,
-            cursor: Default::default(),
+            selected_cursor: Default::default(),
             cursor_grabbed_mode: Mutex::new(CursorGrabMode::None),
             cursor_visible: Mutex::new(true),
             ime_sender: Mutex::new(event_loop.ime_sender.clone()),
@@ -542,11 +547,10 @@ impl UnownedWindow {
                 .ignore_error();
 
             {
-                let result = event_loop
-                    .ime
-                    .borrow_mut()
-                    .create_context(window.xwindow as ffi::Window, false);
-                leap!(result);
+                if let Some(ime) = event_loop.ime.as_ref() {
+                    let result = ime.borrow_mut().create_context(window.xwindow, false, None);
+                    leap!(result);
+                }
             }
 
             // These properties must be set after mapping
@@ -1535,13 +1539,29 @@ impl UnownedWindow {
 
     #[inline]
     pub fn set_cursor_icon(&self, cursor: CursorIcon) {
-        let old_cursor = replace(&mut *self.cursor.lock().unwrap(), cursor);
+        let old_cursor = replace(
+            &mut *self.selected_cursor.lock().unwrap(),
+            SelectedCursor::Named(cursor),
+        );
+
         #[allow(clippy::mutex_atomic)]
-        if cursor != old_cursor && *self.cursor_visible.lock().unwrap() {
+        if SelectedCursor::Named(cursor) != old_cursor && *self.cursor_visible.lock().unwrap() {
             self.xconn.set_cursor_icon(self.xwindow, Some(cursor));
         }
     }
 
+    #[inline]
+    pub fn set_custom_cursor(&self, cursor: RootCustomCursor) {
+        let new_cursor = unsafe { CustomCursor::new(&self.xconn, &cursor.inner) };
+
+        #[allow(clippy::mutex_atomic)]
+        if *self.cursor_visible.lock().unwrap() {
+            self.xconn.set_custom_cursor(self.xwindow, &new_cursor);
+        }
+
+        *self.selected_cursor.lock().unwrap() = SelectedCursor::Custom(new_cursor);
+    }
+
     #[inline]
     pub fn set_cursor_grab(&self, mode: CursorGrabMode) -> Result<(), ExternalError> {
         let mut grabbed_lock = self.cursor_grabbed_mode.lock().unwrap();
@@ -1628,13 +1648,23 @@ impl UnownedWindow {
             return;
         }
         let cursor = if visible {
-            Some(*self.cursor.lock().unwrap())
+            Some((*self.selected_cursor.lock().unwrap()).clone())
         } else {
             None
         };
         *visible_lock = visible;
         drop(visible_lock);
-        self.xconn.set_cursor_icon(self.xwindow, cursor);
+        match cursor {
+            Some(SelectedCursor::Custom(cursor)) => {
+                self.xconn.set_custom_cursor(self.xwindow, &cursor);
+            }
+            Some(SelectedCursor::Named(cursor)) => {
+                self.xconn.set_cursor_icon(self.xwindow, Some(cursor));
+            }
+            None => {
+                self.xconn.set_cursor_icon(self.xwindow, None);
+            }
+        }
     }
 
     #[inline]
@@ -1761,11 +1791,11 @@ impl UnownedWindow {
     #[inline]
     pub fn set_ime_cursor_area(&self, spot: Position, _size: Size) {
         let (x, y) = spot.to_physical::<i32>(self.scale_factor()).into();
-        let _ = self.ime_sender.lock().unwrap().send(ImeRequest::Position(
-            self.xwindow as ffi::Window,
-            x,
-            y,
-        ));
+        let _ = self
+            .ime_sender
+            .lock()
+            .unwrap()
+            .send(ImeRequest::Position(self.xwindow, x, y));
     }
 
     #[inline]
@@ -1774,7 +1804,7 @@ impl UnownedWindow {
             .ime_sender
             .lock()
             .unwrap()
-            .send(ImeRequest::Allow(self.xwindow as ffi::Window, allowed));
+            .send(ImeRequest::Allow(self.xwindow, allowed));
     }
 
     #[inline]

src/platform_impl/linux/x11/xdisplay.rs

@@ -91,6 +91,14 @@ impl XConnection {
             conn.map_err(|e| XNotSupported::XcbConversionError(Arc::new(WrapConnectError(e))))?
         };
 
+        // Make sure Xlib knows XCB is handling events.
+        unsafe {
+            (xlib_xcb.XSetEventQueueOwner)(
+                display,
+                x11_dl::xlib_xcb::XEventQueueOwner::XCBOwnsEventQueue,
+            );
+        }
+
         // Get the default screen.
         let default_screen = unsafe { (xlib.XDefaultScreen)(display) } as usize;
 

src/platform_impl/macos/appkit/application.rs

@@ -80,6 +80,9 @@ extern_methods!(
         #[method(setMainMenu:)]
         pub fn setMainMenu(&self, menu: &NSMenu);
 
+        #[method(setServicesMenu:)]
+        pub fn setServicesMenu(&self, menu: &NSMenu);
+
         #[method_id(effectiveAppearance)]
         pub fn effectiveAppearance(&self) -> Id<NSAppearance>;
 

src/platform_impl/macos/appkit/bitmap_image_rep.rs

@@ -0,0 +1,56 @@
+use std::ffi::c_uchar;
+
+use icrate::Foundation::{NSInteger, NSObject, NSString};
+use objc2::rc::Id;
+use objc2::runtime::Bool;
+use objc2::{extern_class, extern_methods, msg_send, msg_send_id, mutability, ClassType};
+
+extern_class!(
+    #[derive(Debug, PartialEq, Eq, Hash)]
+    pub struct NSImageRep;
+
+    unsafe impl ClassType for NSImageRep {
+        type Super = NSObject;
+        type Mutability = mutability::InteriorMutable;
+    }
+);
+
+extern "C" {
+    static NSDeviceRGBColorSpace: &'static NSString;
+}
+
+extern_class!(
+    // <https://developer.apple.com/documentation/appkit/nsbitmapimagerep?language=objc>
+    #[derive(Debug, PartialEq, Eq, Hash)]
+    pub(crate) struct NSBitmapImageRep;
+
+    unsafe impl ClassType for NSBitmapImageRep {
+        type Super = NSImageRep;
+        type Mutability = mutability::InteriorMutable;
+    }
+);
+
+extern_methods!(
+    unsafe impl NSBitmapImageRep {
+        pub fn init_rgba(width: NSInteger, height: NSInteger) -> Id<Self> {
+            unsafe {
+                msg_send_id![Self::alloc(),
+                    initWithBitmapDataPlanes: std::ptr::null_mut::<*mut c_uchar>(),
+                    pixelsWide: width,
+                    pixelsHigh: height,
+                    bitsPerSample: 8 as NSInteger,
+                    samplesPerPixel: 4 as NSInteger,
+                    hasAlpha: Bool::new(true),
+                    isPlanar: Bool::new(false),
+                    colorSpaceName: NSDeviceRGBColorSpace,
+                    bytesPerRow: width * 4,
+                    bitsPerPixel: 32 as NSInteger,
+                ]
+            }
+        }
+
+        pub fn bitmap_data(&self) -> *mut u8 {
+            unsafe { msg_send![self, bitmapData] }
+        }
+    }
+);

src/platform_impl/macos/appkit/cursor.rs

@@ -2,13 +2,14 @@ use once_cell::sync::Lazy;
 
 use icrate::ns_string;
 use icrate::Foundation::{
-    NSData, NSDictionary, NSNumber, NSObject, NSObjectProtocol, NSPoint, NSString,
+    NSData, NSDictionary, NSNumber, NSObject, NSObjectProtocol, NSPoint, NSSize, NSString,
 };
 use objc2::rc::{DefaultId, Id};
 use objc2::runtime::Sel;
 use objc2::{extern_class, extern_methods, msg_send_id, mutability, sel, ClassType};
 
-use super::NSImage;
+use super::{NSBitmapImageRep, NSImage};
+use crate::cursor::CursorImage;
 use crate::window::CursorIcon;
 
 extern_class!(
@@ -232,6 +233,23 @@ impl NSCursor {
             _ => Default::default(),
         }
     }
+
+    pub fn from_image(cursor: &CursorImage) -> Id<Self> {
+        let width = cursor.width;
+        let height = cursor.height;
+
+        let bitmap = NSBitmapImageRep::init_rgba(width as isize, height as isize);
+        let bitmap_data =
+            unsafe { std::slice::from_raw_parts_mut(bitmap.bitmap_data(), cursor.rgba.len()) };
+        bitmap_data.copy_from_slice(&cursor.rgba);
+
+        let image = NSImage::init_with_size(NSSize::new(width.into(), height.into()));
+        image.add_representation(&bitmap);
+
+        let hotspot = NSPoint::new(cursor.hotspot_x as f64, cursor.hotspot_y as f64);
+
+        NSCursor::new(&image, hotspot)
+    }
 }
 
 impl DefaultId for NSCursor {

src/platform_impl/macos/appkit/image.rs

@@ -1,6 +1,8 @@
-use icrate::Foundation::{NSData, NSObject, NSString};
+use icrate::Foundation::{NSData, NSObject, NSSize, NSString};
 use objc2::rc::Id;
-use objc2::{extern_class, extern_methods, msg_send_id, mutability, ClassType};
+use objc2::{extern_class, extern_methods, msg_send, msg_send_id, mutability, ClassType};
+
+use super::NSBitmapImageRep;
 
 extern_class!(
     // TODO: Can this be mutable?
@@ -32,5 +34,13 @@ extern_methods!(
         pub fn new_with_data(data: &NSData) -> Id<Self> {
             unsafe { msg_send_id![Self::alloc(), initWithData: data] }
         }
+
+        pub fn init_with_size(size: NSSize) -> Id<Self> {
+            unsafe { msg_send_id![Self::alloc(), initWithSize: size] }
+        }
+
+        pub fn add_representation(&self, representation: &NSBitmapImageRep) {
+            unsafe { msg_send![self, addRepresentation: representation] }
+        }
     }
 );

src/platform_impl/macos/appkit/menu_item.rs

@@ -20,7 +20,11 @@ extern_methods!(
         #[method_id(new)]
         pub fn new() -> Id<Self>;
 
-        pub fn newWithTitle(title: &NSString, action: Sel, key_equivalent: &NSString) -> Id<Self> {
+        pub fn newWithTitle(
+            title: &NSString,
+            action: Option<Sel>,
+            key_equivalent: &NSString,
+        ) -> Id<Self> {
             unsafe {
                 msg_send_id![
                     Self::alloc(),

src/platform_impl/macos/appkit/mod.rs

@@ -13,6 +13,7 @@
 
 mod appearance;
 mod application;
+mod bitmap_image_rep;
 mod button;
 mod color;
 mod control;
@@ -36,6 +37,7 @@ pub(crate) use self::application::{
     NSApp, NSApplication, NSApplicationActivationPolicy, NSApplicationPresentationOptions,
     NSRequestUserAttentionType,
 };
+pub(crate) use self::bitmap_image_rep::NSBitmapImageRep;
 pub(crate) use self::button::NSButton;
 pub(crate) use self::color::NSColor;
 pub(crate) use self::control::NSControl;

src/platform_impl/macos/menu.rs

@@ -21,7 +21,16 @@ pub fn initialize() {
 
     // About menu item
     let about_item_title = ns_string!("About ").stringByAppendingString(&process_name);
-    let about_item = menu_item(&about_item_title, sel!(orderFrontStandardAboutPanel:), None);
+    let about_item = menu_item(
+        &about_item_title,
+        Some(sel!(orderFrontStandardAboutPanel:)),
+        None,
+    );
+
+    // Services menu item
+    let services_menu = NSMenu::new();
+    let services_item = menu_item(ns_string!("Services"), None, None);
+    services_item.setSubmenu(&services_menu);
 
     // Seperator menu item
     let sep_first = NSMenuItem::separatorItem();
@@ -30,7 +39,7 @@ pub fn initialize() {
     let hide_item_title = ns_string!("Hide ").stringByAppendingString(&process_name);
     let hide_item = menu_item(
         &hide_item_title,
-        sel!(hide:),
+        Some(sel!(hide:)),
         Some(KeyEquivalent {
             key: ns_string!("h"),
             masks: None,
@@ -41,7 +50,7 @@ pub fn initialize() {
     let hide_others_item_title = ns_string!("Hide Others");
     let hide_others_item = menu_item(
         hide_others_item_title,
-        sel!(hideOtherApplications:),
+        Some(sel!(hideOtherApplications:)),
         Some(KeyEquivalent {
             key: ns_string!("h"),
             masks: Some(
@@ -52,7 +61,11 @@ pub fn initialize() {
 
     // Show applications menu item
     let show_all_item_title = ns_string!("Show All");
-    let show_all_item = menu_item(show_all_item_title, sel!(unhideAllApplications:), None);
+    let show_all_item = menu_item(
+        show_all_item_title,
+        Some(sel!(unhideAllApplications:)),
+        None,
+    );
 
     // Seperator menu item
     let sep = NSMenuItem::separatorItem();
@@ -61,7 +74,7 @@ pub fn initialize() {
     let quit_item_title = ns_string!("Quit ").stringByAppendingString(&process_name);
     let quit_item = menu_item(
         &quit_item_title,
-        sel!(terminate:),
+        Some(sel!(terminate:)),
         Some(KeyEquivalent {
             key: ns_string!("q"),
             masks: None,
@@ -70,6 +83,7 @@ pub fn initialize() {
 
     app_menu.addItem(&about_item);
     app_menu.addItem(&sep_first);
+    app_menu.addItem(&services_item);
     app_menu.addItem(&hide_item);
     app_menu.addItem(&hide_others_item);
     app_menu.addItem(&show_all_item);
@@ -78,12 +92,13 @@ pub fn initialize() {
     app_menu_item.setSubmenu(&app_menu);
 
     let app = NSApp();
+    app.setServicesMenu(&services_menu);
     app.setMainMenu(&menubar);
 }
 
 fn menu_item(
     title: &NSString,
-    selector: Sel,
+    selector: Option<Sel>,
     key_equivalent: Option<KeyEquivalent<'_>>,
 ) -> Id<NSMenuItem> {
     let (key, masks) = match key_equivalent {

src/platform_impl/macos/mod.rs

@@ -28,6 +28,7 @@ pub(crate) use self::{
 use crate::event::DeviceId as RootDeviceId;
 
 pub(crate) use self::window::Window;
+pub(crate) use crate::cursor::CursorImage as PlatformCustomCursor;
 pub(crate) use crate::icon::NoIcon as PlatformIcon;
 pub(crate) use crate::platform_impl::Fullscreen;
 

src/platform_impl/macos/window.rs

@@ -7,6 +7,7 @@ use std::os::raw::c_void;
 use std::ptr::NonNull;
 use std::sync::{Mutex, MutexGuard};
 
+use crate::cursor::CustomCursor;
 use crate::{
     dpi::{
         LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize, Position, Size, Size::Logical,
@@ -834,6 +835,13 @@ impl WinitWindow {
         self.invalidateCursorRectsForView(&view);
     }
 
+    #[inline]
+    pub fn set_custom_cursor(&self, cursor: CustomCursor) {
+        let view = self.view();
+        view.set_cursor_icon(NSCursor::from_image(&cursor.inner));
+        self.invalidateCursorRectsForView(&view);
+    }
+
     #[inline]
     pub fn set_cursor_grab(&self, mode: CursorGrabMode) -> Result<(), ExternalError> {
         let associate_mouse_cursor = match mode {

src/platform_impl/orbital/mod.rs

@@ -193,6 +193,7 @@ impl Display for OsError {
     }
 }
 
+pub(crate) use crate::cursor::NoCustomCursor as PlatformCustomCursor;
 pub(crate) use crate::icon::NoIcon as PlatformIcon;
 
 #[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]

src/platform_impl/orbital/window.rs

@@ -4,6 +4,7 @@ use std::{
 };
 
 use crate::{
+    cursor::CustomCursor,
     dpi::{PhysicalPosition, PhysicalSize, Position, Size},
     error,
     platform_impl::Fullscreen,
@@ -352,6 +353,8 @@ impl Window {
     #[inline]
     pub fn set_cursor_icon(&self, _: window::CursorIcon) {}
 
+    pub fn set_custom_cursor(&self, _: CustomCursor) {}
+
     #[inline]
     pub fn set_cursor_position(&self, _: Position) -> Result<(), error::ExternalError> {
         Err(error::ExternalError::NotSupported(

src/platform_impl/web/cursor.rs

@@ -0,0 +1,364 @@
+use std::{
+    cell::{Cell, RefCell},
+    ops::Deref,
+    rc::{Rc, Weak},
+};
+
+use crate::cursor::{BadImage, CursorImage};
+use cursor_icon::CursorIcon;
+use wasm_bindgen::{closure::Closure, JsCast};
+use wasm_bindgen_futures::JsFuture;
+use web_sys::{
+    Blob, Document, HtmlCanvasElement, ImageBitmap, ImageBitmapOptions,
+    ImageBitmapRenderingContext, ImageData, PremultiplyAlpha, Url, Window,
+};
+
+use super::backend::Style;
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum WebCustomCursor {
+    Image(CursorImage),
+    Url {
+        url: String,
+        hotspot_x: u16,
+        hotspot_y: u16,
+    },
+}
+
+impl WebCustomCursor {
+    pub fn from_rgba(
+        rgba: Vec<u8>,
+        width: u16,
+        height: u16,
+        hotspot_x: u16,
+        hotspot_y: u16,
+    ) -> Result<Self, BadImage> {
+        Ok(Self::Image(CursorImage::from_rgba(
+            rgba, width, height, hotspot_x, hotspot_y,
+        )?))
+    }
+
+    pub(super) fn build(
+        &self,
+        window: &Window,
+        document: &Document,
+        style: &Style,
+        previous: SelectedCursor,
+        cursor_visible: Rc<Cell<bool>>,
+    ) -> SelectedCursor {
+        let previous = previous.into();
+
+        match self {
+            WebCustomCursor::Image(image) => SelectedCursor::Image(CursorImageState::from_image(
+                window,
+                document.clone(),
+                style.clone(),
+                image,
+                previous,
+                cursor_visible,
+            )),
+            WebCustomCursor::Url {
+                url,
+                hotspot_x,
+                hotspot_y,
+            } => {
+                let value = previous.style_with_url(url, *hotspot_x, *hotspot_y);
+
+                if cursor_visible.get() {
+                    style.set("cursor", &value);
+                }
+
+                SelectedCursor::Url {
+                    style: value,
+                    previous,
+                    url: url.clone(),
+                    hotspot_x: *hotspot_x,
+                    hotspot_y: *hotspot_y,
+                }
+            }
+        }
+    }
+}
+
+#[derive(Debug)]
+pub enum SelectedCursor {
+    Named(CursorIcon),
+    Url {
+        style: String,
+        previous: Previous,
+        url: String,
+        hotspot_x: u16,
+        hotspot_y: u16,
+    },
+    Image(Rc<RefCell<Option<CursorImageState>>>),
+}
+
+impl Default for SelectedCursor {
+    fn default() -> Self {
+        Self::Named(Default::default())
+    }
+}
+
+impl SelectedCursor {
+    pub fn set_style(&self, style: &Style) {
+        let value = match self {
+            SelectedCursor::Named(icon) => icon.name(),
+            SelectedCursor::Url { style, .. } => style,
+            SelectedCursor::Image(image) => {
+                let image = image.borrow();
+                let value = match image.deref().as_ref().unwrap() {
+                    CursorImageState::Loading { previous, .. } => previous.style(),
+                    CursorImageState::Failed(previous) => previous.style(),
+                    CursorImageState::Ready { style, .. } => style,
+                };
+                return style.set("cursor", value);
+            }
+        };
+
+        style.set("cursor", value);
+    }
+}
+
+#[derive(Debug)]
+pub enum Previous {
+    Named(CursorIcon),
+    Url {
+        style: String,
+        url: String,
+        hotspot_x: u16,
+        hotspot_y: u16,
+    },
+    Image {
+        style: String,
+        image: WebCursorImage,
+    },
+}
+
+impl Previous {
+    fn style(&self) -> &str {
+        match self {
+            Previous::Named(icon) => icon.name(),
+            Previous::Url { style: url, .. } => url,
+            Previous::Image { style, .. } => style,
+        }
+    }
+
+    fn style_with_url(&self, new_url: &str, new_hotspot_x: u16, new_hotspot_y: u16) -> String {
+        match self {
+            Previous::Named(icon) => format!("url({new_url}) {new_hotspot_x} {new_hotspot_y}, {}", icon.name()),
+            Previous::Url {
+                url,
+                hotspot_x,
+                hotspot_y,
+                ..
+            }
+            | Previous::Image {
+                image:
+                    WebCursorImage {
+                        data_url: url,
+                        hotspot_x,
+                        hotspot_y,
+                        ..
+                    },
+                ..
+            } => format!(
+                "url({new_url}) {new_hotspot_x} {new_hotspot_y}, url({url}) {hotspot_x} {hotspot_y}, auto",
+            ),
+        }
+    }
+}
+
+impl From<SelectedCursor> for Previous {
+    fn from(value: SelectedCursor) -> Self {
+        match value {
+            SelectedCursor::Named(icon) => Self::Named(icon),
+            SelectedCursor::Url {
+                style,
+                url,
+                hotspot_x,
+                hotspot_y,
+                ..
+            } => Self::Url {
+                style,
+                url,
+                hotspot_x,
+                hotspot_y,
+            },
+            SelectedCursor::Image(image) => {
+                match Rc::try_unwrap(image).unwrap().into_inner().unwrap() {
+                    CursorImageState::Loading { previous, .. } => previous,
+                    CursorImageState::Failed(previous) => previous,
+                    CursorImageState::Ready {
+                        style,
+                        image: current,
+                        ..
+                    } => Self::Image {
+                        style,
+                        image: current,
+                    },
+                }
+            }
+        }
+    }
+}
+
+#[derive(Debug)]
+pub enum CursorImageState {
+    Loading {
+        style: Style,
+        cursor_visible: Rc<Cell<bool>>,
+        previous: Previous,
+        hotspot_x: u16,
+        hotspot_y: u16,
+    },
+    Failed(Previous),
+    Ready {
+        style: String,
+        image: WebCursorImage,
+        previous: Previous,
+    },
+}
+
+impl CursorImageState {
+    fn from_image(
+        window: &Window,
+        document: Document,
+        style: Style,
+        image: &CursorImage,
+        previous: Previous,
+        cursor_visible: Rc<Cell<bool>>,
+    ) -> Rc<RefCell<Option<Self>>> {
+        // Can't create array directly when backed by SharedArrayBuffer.
+        // Adapted from https://github.com/rust-windowing/softbuffer/blob/ab7688e2ed2e2eca51b3c4e1863a5bd7fe85800e/src/web.rs#L196-L223
+        #[cfg(target_feature = "atomics")]
+        let image_data = {
+            use js_sys::{Uint8Array, Uint8ClampedArray};
+            use wasm_bindgen::prelude::wasm_bindgen;
+            use wasm_bindgen::JsValue;
+
+            #[wasm_bindgen]
+            extern "C" {
+                #[wasm_bindgen(js_namespace = ImageData)]
+                type ImageDataExt;
+                #[wasm_bindgen(catch, constructor, js_class = ImageData)]
+                fn new(array: Uint8ClampedArray, sw: u32) -> Result<ImageDataExt, JsValue>;
+            }
+
+            let array = Uint8Array::new_with_length(image.rgba.len() as u32);
+            array.copy_from(&image.rgba);
+            let array = Uint8ClampedArray::new(&array);
+            ImageDataExt::new(array, image.width as u32)
+                .map(JsValue::from)
+                .map(ImageData::unchecked_from_js)
+                .unwrap()
+        };
+        #[cfg(not(target_feature = "atomics"))]
+        let image_data = ImageData::new_with_u8_clamped_array(
+            wasm_bindgen::Clamped(&image.rgba),
+            image.width as u32,
+        )
+        .unwrap();
+
+        let mut options = ImageBitmapOptions::new();
+        options.premultiply_alpha(PremultiplyAlpha::None);
+        let bitmap = JsFuture::from(
+            window
+                .create_image_bitmap_with_image_data_and_image_bitmap_options(&image_data, &options)
+                .unwrap(),
+        );
+
+        let state = Rc::new(RefCell::new(Some(Self::Loading {
+            style,
+            cursor_visible,
+            previous,
+            hotspot_x: image.hotspot_x,
+            hotspot_y: image.hotspot_y,
+        })));
+
+        wasm_bindgen_futures::spawn_local({
+            let weak = Rc::downgrade(&state);
+            let CursorImage { width, height, .. } = *image;
+            async move {
+                if weak.strong_count() == 0 {
+                    return;
+                }
+
+                let bitmap: ImageBitmap = bitmap.await.unwrap().unchecked_into();
+
+                if weak.strong_count() == 0 {
+                    return;
+                }
+
+                let canvas: HtmlCanvasElement =
+                    document.create_element("canvas").unwrap().unchecked_into();
+                #[allow(clippy::disallowed_methods)]
+                canvas.set_width(width as u32);
+                #[allow(clippy::disallowed_methods)]
+                canvas.set_height(height as u32);
+
+                let context: ImageBitmapRenderingContext = canvas
+                    .get_context("bitmaprenderer")
+                    .unwrap()
+                    .unwrap()
+                    .unchecked_into();
+                context.transfer_from_image_bitmap(&bitmap);
+
+                thread_local! {
+                    static CURRENT_STATE: RefCell<Option<Weak<RefCell<Option<CursorImageState>>>>> = RefCell::new(None);
+                    // `HTMLCanvasElement.toBlob()` can't be interrupted. So we have to use a
+                    // `Closure` that doesn't need to be garbage-collected.
+                    static CALLBACK: Closure<dyn Fn(Option<Blob>)> = Closure::new(|blob| {
+                        CURRENT_STATE.with(|weak| {
+                            let Some(state) = weak.borrow_mut().take().and_then(|weak| weak.upgrade()) else {
+                                return;
+                            };
+                            let mut state = state.borrow_mut();
+                            // Extract old state.
+                            let CursorImageState::Loading { style, cursor_visible, previous, hotspot_x, hotspot_y, .. } = state.take().unwrap() else {
+                                unreachable!("found invalid state")
+                            };
+
+                            let Some(blob) = blob else {
+                                *state = Some(CursorImageState::Failed(previous));
+                                return;
+                            };
+                            let data_url = Url::create_object_url_with_blob(&blob).unwrap();
+
+                            let value = previous.style_with_url(&data_url, hotspot_x, hotspot_y);
+
+                            if cursor_visible.get() {
+                                style.set("cursor", &value);
+                            }
+
+                            *state = Some(
+                                CursorImageState::Ready {
+                                    style: value,
+                                    image: WebCursorImage{ data_url, hotspot_x, hotspot_y },
+                                    previous,
+                                });
+                        });
+                    });
+                }
+
+                CURRENT_STATE.with(|state| *state.borrow_mut() = Some(weak));
+                CALLBACK
+                    .with(|callback| canvas.to_blob(callback.as_ref().unchecked_ref()).unwrap());
+            }
+        });
+
+        state
+    }
+}
+
+#[derive(Debug)]
+pub struct WebCursorImage {
+    data_url: String,
+    hotspot_x: u16,
+    hotspot_y: u16,
+}
+
+impl Drop for WebCursorImage {
+    fn drop(&mut self) {
+        Url::revoke_object_url(&self.data_url).unwrap();
+    }
+}

src/platform_impl/web/event_loop/runner.rs

@@ -67,7 +67,6 @@ pub struct Execution {
     on_key_press: OnEventHandle<KeyboardEvent>,
     on_key_release: OnEventHandle<KeyboardEvent>,
     on_visibility_change: OnEventHandle<web_sys::Event>,
-    on_touch_end: OnEventHandle<web_sys::Event>,
 }
 
 enum RunnerEnum {
@@ -181,7 +180,6 @@ impl Shared {
                 on_key_press: RefCell::new(None),
                 on_key_release: RefCell::new(None),
                 on_visibility_change: RefCell::new(None),
-                on_touch_end: RefCell::new(None),
             }
         }))
     }
@@ -342,8 +340,6 @@ impl Shared {
             self.window().clone(),
             "pointerdown",
             Closure::new(move |event: PointerEvent| {
-                runner.transient_activation();
-
                 if !runner.device_events() {
                     return;
                 }
@@ -367,8 +363,6 @@ impl Shared {
             self.window().clone(),
             "pointerup",
             Closure::new(move |event: PointerEvent| {
-                runner.transient_activation();
-
                 if !runner.device_events() {
                     return;
                 }
@@ -392,8 +386,6 @@ impl Shared {
             self.window().clone(),
             "keydown",
             Closure::new(move |event: KeyboardEvent| {
-                runner.transient_activation();
-
                 if !runner.device_events() {
                     return;
                 }
@@ -452,14 +444,6 @@ impl Shared {
                 }
             }),
         ));
-        let runner = self.clone();
-        *self.0.on_touch_end.borrow_mut() = Some(EventListenerHandle::new(
-            self.window().clone(),
-            "touchend",
-            Closure::new(move |_| {
-                runner.transient_activation();
-            }),
-        ));
     }
 
     // Generate a strictly increasing ID
@@ -788,18 +772,6 @@ impl Shared {
         }
     }
 
-    fn transient_activation(&self) {
-        self.0
-            .all_canvases
-            .borrow()
-            .iter()
-            .for_each(|(_, canvas, _)| {
-                if let Some(canvas) = canvas.upgrade() {
-                    canvas.borrow().transient_activation();
-                }
-            });
-    }
-
     pub fn event_loop_recreation(&self, allow: bool) {
         self.0.event_loop_recreation.set(allow)
     }

src/platform_impl/web/event_loop/window_target.rs

@@ -647,8 +647,6 @@ impl<T> EventLoopWindowTarget<T> {
 
         let runner = self.runner.clone();
         canvas.on_animation_frame(move || runner.request_redraw(RootWindowId(id)));
-
-        canvas.on_touch_end();
     }
 
     pub fn available_monitors(&self) -> VecDequeIter<MonitorHandle> {

src/platform_impl/web/mod.rs

@@ -18,6 +18,7 @@
 // compliant way.
 
 mod r#async;
+mod cursor;
 mod device;
 mod error;
 mod event_loop;
@@ -39,3 +40,4 @@ pub use self::window::{PlatformSpecificWindowBuilderAttributes, Window, WindowId
 pub(crate) use self::keyboard::KeyEventExtra;
 pub(crate) use crate::icon::NoIcon as PlatformIcon;
 pub(crate) use crate::platform_impl::Fullscreen;
+pub(crate) use cursor::WebCustomCursor as PlatformCustomCursor;

src/platform_impl/web/web_sys/canvas.rs

@@ -1,5 +1,5 @@
 use std::cell::Cell;
-use std::rc::{Rc, Weak};
+use std::rc::Rc;
 use std::sync::{Arc, Mutex};
 
 use smol_str::SmolStr;
@@ -18,11 +18,10 @@ use crate::window::{WindowAttributes, WindowId as RootWindowId};
 use super::super::WindowId;
 use super::animation_frame::AnimationFrameHandler;
 use super::event_handle::EventListenerHandle;
-use super::fullscreen::FullscreenHandler;
 use super::intersection_handle::IntersectionObserverHandle;
 use super::media_query_handle::MediaQueryListHandle;
 use super::pointer::PointerHandler;
-use super::{event, ButtonsState, ResizeScaleHandle};
+use super::{event, fullscreen, ButtonsState, ResizeScaleHandle};
 
 #[allow(dead_code)]
 pub struct Canvas {
@@ -49,10 +48,15 @@ pub struct Common {
     pub document: Document,
     /// Note: resizing the HTMLCanvasElement should go through `backend::set_canvas_size` to ensure the DPI factor is maintained.
     pub raw: HtmlCanvasElement,
-    style: CssStyleDeclaration,
+    style: Style,
     old_size: Rc<Cell<PhysicalSize<u32>>>,
     current_size: Rc<Cell<PhysicalSize<u32>>>,
-    fullscreen_handler: Rc<FullscreenHandler>,
+}
+
+#[derive(Clone, Debug)]
+pub struct Style {
+    read: CssStyleDeclaration,
+    write: CssStyleDeclaration,
 }
 
 impl Canvas {
@@ -90,12 +94,7 @@ impl Canvas {
                 .map_err(|_| os_error!(OsError("Failed to set a tabindex".to_owned())))?;
         }
 
-        #[allow(clippy::disallowed_methods)]
-        let style = window
-            .get_computed_style(&canvas)
-            .expect("Failed to obtain computed style")
-            // this can't fail: we aren't using a pseudo-element
-            .expect("Invalid pseudo-element");
+        let style = Style::new(&window, &canvas);
 
         let common = Common {
             window: window.clone(),
@@ -104,7 +103,6 @@ impl Canvas {
             style,
             old_size: Rc::default(),
             current_size: Rc::default(),
-            fullscreen_handler: Rc::new(FullscreenHandler::new(document.clone(), canvas.clone())),
         };
 
         if let Some(size) = attr.inner_size {
@@ -128,7 +126,7 @@ impl Canvas {
         }
 
         if attr.fullscreen.0.is_some() {
-            common.fullscreen_handler.request_fullscreen();
+            fullscreen::request_fullscreen(&document, &canvas);
         }
 
         if attr.active {
@@ -178,9 +176,7 @@ impl Canvas {
             y: bounds.y(),
         };
 
-        if self.document().contains(Some(self.raw()))
-            && self.style().get_property_value("display").unwrap() != "none"
-        {
+        if self.document().contains(Some(self.raw())) && self.style().get("display") != "none" {
             position.x += super::style_size_property(self.style(), "border-left-width")
                 + super::style_size_property(self.style(), "padding-left");
             position.y += super::style_size_property(self.style(), "border-top-width")
@@ -226,7 +222,7 @@ impl Canvas {
     }
 
     #[inline]
-    pub fn style(&self) -> &CssStyleDeclaration {
+    pub fn style(&self) -> &Style {
         &self.common.style
     }
 
@@ -282,7 +278,7 @@ impl Canvas {
     where
         F: 'static + FnMut(PhysicalKey, Key, Option<SmolStr>, KeyLocation, bool, ModifiersState),
     {
-        self.on_keyboard_press = Some(self.common.add_transient_event(
+        self.on_keyboard_press = Some(self.common.add_event(
             "keydown",
             move |event: KeyboardEvent| {
                 if prevent_default {
@@ -442,20 +438,16 @@ impl Canvas {
         self.animation_frame_handler.on_animation_frame(f)
     }
 
-    pub(crate) fn on_touch_end(&mut self) {
-        self.on_touch_end = Some(self.common.add_transient_event("touchend", |_| {}));
-    }
-
     pub fn request_fullscreen(&self) {
-        self.common.fullscreen_handler.request_fullscreen()
+        fullscreen::request_fullscreen(self.document(), self.raw());
     }
 
     pub fn exit_fullscreen(&self) {
-        self.common.fullscreen_handler.exit_fullscreen()
+        fullscreen::exit_fullscreen(self.document(), self.raw());
     }
 
     pub fn is_fullscreen(&self) -> bool {
-        self.common.fullscreen_handler.is_fullscreen()
+        fullscreen::is_fullscreen(self.document(), self.raw())
     }
 
     pub fn request_animation_frame(&self) {
@@ -506,10 +498,6 @@ impl Canvas {
         }
     }
 
-    pub(crate) fn transient_activation(&self) {
-        self.common.fullscreen_handler.transient_activation()
-    }
-
     pub fn remove_listeners(&mut self) {
         self.on_touch_start = None;
         self.on_focus = None;
@@ -523,7 +511,6 @@ impl Canvas {
         self.on_intersect = None;
         self.animation_frame_handler.cancel();
         self.on_touch_end = None;
-        self.common.fullscreen_handler.cancel();
     }
 }
 
@@ -539,27 +526,38 @@ impl Common {
     {
         EventListenerHandle::new(self.raw.clone(), event_name, Closure::new(handler))
     }
+}
 
-    // The difference between add_event and add_user_event is that the latter has a special meaning
-    // for browser security. A user event is a deliberate action by the user (like a mouse or key
-    // press) and is the only time things like a fullscreen request may be successfully completed.)
-    pub fn add_transient_event<E, F>(
-        &self,
-        event_name: &'static str,
-        mut handler: F,
-    ) -> EventListenerHandle<dyn FnMut(E)>
-    where
-        E: 'static + AsRef<web_sys::Event> + wasm_bindgen::convert::FromWasmAbi,
-        F: 'static + FnMut(E),
-    {
-        let fullscreen_handler = Rc::downgrade(&self.fullscreen_handler);
+impl Style {
+    fn new(window: &web_sys::Window, canvas: &HtmlCanvasElement) -> Self {
+        #[allow(clippy::disallowed_methods)]
+        let read = window
+            .get_computed_style(canvas)
+            .expect("Failed to obtain computed style")
+            // this can't fail: we aren't using a pseudo-element
+            .expect("Invalid pseudo-element");
 
-        self.add_event(event_name, move |event: E| {
-            handler(event);
+        #[allow(clippy::disallowed_methods)]
+        let write = canvas.style();
 
-            if let Some(fullscreen_handler) = Weak::upgrade(&fullscreen_handler) {
-                fullscreen_handler.transient_activation()
-            }
-        })
+        Self { read, write }
+    }
+
+    pub(crate) fn get(&self, property: &str) -> String {
+        self.read
+            .get_property_value(property)
+            .expect("Invalid property")
+    }
+
+    pub(crate) fn remove(&self, property: &str) {
+        self.write
+            .remove_property(property)
+            .expect("Property is read only");
+    }
+
+    pub(crate) fn set(&self, property: &str, value: &str) {
+        self.write
+            .set_property(property, value)
+            .expect("Property is read only");
     }
 }

src/platform_impl/web/web_sys/fullscreen.rs

@@ -1,6 +1,3 @@
-use std::cell::Cell;
-use std::rc::Rc;
-
 use js_sys::Promise;
 use once_cell::unsync::OnceCell;
 use wasm_bindgen::closure::Closure;
@@ -8,138 +5,86 @@ use wasm_bindgen::prelude::wasm_bindgen;
 use wasm_bindgen::{JsCast, JsValue};
 use web_sys::{Document, Element, HtmlCanvasElement};
 
-use super::EventListenerHandle;
+pub fn request_fullscreen(document: &Document, canvas: &HtmlCanvasElement) {
+    if is_fullscreen(document, canvas) {
+        return;
+    }
 
-thread_local! {
-    static FULLSCREEN_API_SUPPORT: OnceCell<bool> = OnceCell::new();
+    #[wasm_bindgen]
+    extern "C" {
+        #[wasm_bindgen(extends = HtmlCanvasElement)]
+        type RequestFullscreen;
+
+        #[wasm_bindgen(method, js_name = requestFullscreen)]
+        fn request_fullscreen(this: &RequestFullscreen) -> Promise;
+
+        #[wasm_bindgen(method, js_name = webkitRequestFullscreen)]
+        fn webkit_request_fullscreen(this: &RequestFullscreen);
+    }
+
+    let canvas: &RequestFullscreen = canvas.unchecked_ref();
+
+    if has_fullscreen_api_support(canvas) {
+        thread_local! {
+            static REJECT_HANDLER: Closure<dyn FnMut(JsValue)> = Closure::new(|_| ());
+        }
+        REJECT_HANDLER.with(|handler| {
+            let _ = canvas.request_fullscreen().catch(handler);
+        });
+    } else {
+        canvas.webkit_request_fullscreen();
+    }
 }
 
-pub struct FullscreenHandler {
-    document: Document,
-    canvas: HtmlCanvasElement,
-    fullscreen_requested: Rc<Cell<bool>>,
-    _fullscreen_change: EventListenerHandle<dyn FnMut()>,
+pub fn is_fullscreen(document: &Document, canvas: &HtmlCanvasElement) -> bool {
+    #[wasm_bindgen]
+    extern "C" {
+        type FullscreenElement;
+
+        #[wasm_bindgen(method, getter, js_name = webkitFullscreenElement)]
+        fn webkit_fullscreen_element(this: &FullscreenElement) -> Option<Element>;
+    }
+
+    let element = if has_fullscreen_api_support(canvas) {
+        #[allow(clippy::disallowed_methods)]
+        document.fullscreen_element()
+    } else {
+        let document: &FullscreenElement = document.unchecked_ref();
+        document.webkit_fullscreen_element()
+    };
+
+    match element {
+        Some(element) => {
+            let canvas: &Element = canvas;
+            canvas == &element
+        }
+        None => false,
+    }
 }
 
-impl FullscreenHandler {
-    pub fn new(document: Document, canvas: HtmlCanvasElement) -> Self {
-        let fullscreen_requested = Rc::new(Cell::new(false));
-        let fullscreen_change = EventListenerHandle::new(
-            canvas.clone(),
-            if has_fullscreen_api_support(&canvas) {
-                "fullscreenchange"
-            } else {
-                "webkitfullscreenchange"
-            },
-            Closure::new({
-                let fullscreen_requested = fullscreen_requested.clone();
-                move || {
-                    // It doesn't matter if the canvas entered or exitted fullscreen mode,
-                    // we don't want to request it again later.
-                    fullscreen_requested.set(false);
-                }
-            }),
-        );
+pub fn exit_fullscreen(document: &Document, canvas: &HtmlCanvasElement) {
+    #[wasm_bindgen]
+    extern "C" {
+        type ExitFullscreen;
 
-        Self {
-            document,
-            canvas,
-            fullscreen_requested,
-            _fullscreen_change: fullscreen_change,
-        }
+        #[wasm_bindgen(method, js_name = webkitExitFullscreen)]
+        fn webkit_exit_fullscreen(this: &ExitFullscreen);
     }
 
-    fn internal_request_fullscreen(&self) {
-        #[wasm_bindgen]
-        extern "C" {
-            type RequestFullscreen;
-
-            #[wasm_bindgen(method, js_name = requestFullscreen)]
-            fn request_fullscreen(this: &RequestFullscreen) -> Promise;
-
-            #[wasm_bindgen(method, js_name = webkitRequestFullscreen)]
-            fn webkit_request_fullscreen(this: &RequestFullscreen);
-        }
-
-        let canvas: &RequestFullscreen = self.canvas.unchecked_ref();
-
-        if has_fullscreen_api_support(&self.canvas) {
-            thread_local! {
-                static REJECT_HANDLER: Closure<dyn FnMut(JsValue)> = Closure::new(|_| ());
-            }
-            REJECT_HANDLER.with(|handler| {
-                let _ = canvas.request_fullscreen().catch(handler);
-            });
-        } else {
-            canvas.webkit_request_fullscreen();
-        }
-    }
-
-    pub fn request_fullscreen(&self) {
-        if !self.is_fullscreen() {
-            self.internal_request_fullscreen();
-            self.fullscreen_requested.set(true);
-        }
-    }
-
-    pub fn transient_activation(&self) {
-        if self.fullscreen_requested.get() {
-            self.internal_request_fullscreen()
-        }
-    }
-
-    pub fn is_fullscreen(&self) -> bool {
-        #[wasm_bindgen]
-        extern "C" {
-            type FullscreenElement;
-
-            #[wasm_bindgen(method, getter, js_name = webkitFullscreenElement)]
-            fn webkit_fullscreen_element(this: &FullscreenElement) -> Option<Element>;
-        }
-
-        let element = if has_fullscreen_api_support(&self.canvas) {
-            #[allow(clippy::disallowed_methods)]
-            self.document.fullscreen_element()
-        } else {
-            let document: &FullscreenElement = self.document.unchecked_ref();
-            document.webkit_fullscreen_element()
-        };
-
-        match element {
-            Some(element) => {
-                let canvas: &Element = &self.canvas;
-                canvas == &element
-            }
-            None => false,
-        }
-    }
-
-    pub fn exit_fullscreen(&self) {
-        #[wasm_bindgen]
-        extern "C" {
-            type ExitFullscreen;
-
-            #[wasm_bindgen(method, js_name = webkitExitFullscreen)]
-            fn webkit_exit_fullscreen(this: &ExitFullscreen);
-        }
-
-        if has_fullscreen_api_support(&self.canvas) {
-            #[allow(clippy::disallowed_methods)]
-            self.document.exit_fullscreen()
-        } else {
-            let document: &ExitFullscreen = self.document.unchecked_ref();
-            document.webkit_exit_fullscreen()
-        }
-
-        self.fullscreen_requested.set(false);
-    }
-
-    pub fn cancel(&self) {
-        self.fullscreen_requested.set(false);
+    if has_fullscreen_api_support(canvas) {
+        #[allow(clippy::disallowed_methods)]
+        document.exit_fullscreen()
+    } else {
+        let document: &ExitFullscreen = document.unchecked_ref();
+        document.webkit_exit_fullscreen()
     }
 }
 
 fn has_fullscreen_api_support(canvas: &HtmlCanvasElement) -> bool {
+    thread_local! {
+        static FULLSCREEN_API_SUPPORT: OnceCell<bool> = OnceCell::new();
+    }
+
     FULLSCREEN_API_SUPPORT.with(|support| {
         *support.get_or_init(|| {
             #[wasm_bindgen]

src/platform_impl/web/web_sys/mod.rs

@@ -10,6 +10,7 @@ mod resize_scaling;
 mod schedule;
 
 pub use self::canvas::Canvas;
+pub use self::canvas::Style;
 pub use self::event::ButtonsState;
 pub use self::event_handle::EventListenerHandle;
 pub use self::resize_scaling::ResizeScaleHandle;
@@ -17,9 +18,7 @@ pub use self::schedule::Schedule;
 
 use crate::dpi::{LogicalPosition, LogicalSize};
 use wasm_bindgen::closure::Closure;
-use web_sys::{
-    CssStyleDeclaration, Document, HtmlCanvasElement, PageTransitionEvent, VisibilityState,
-};
+use web_sys::{Document, HtmlCanvasElement, PageTransitionEvent, VisibilityState};
 
 pub fn throw(msg: &str) {
     wasm_bindgen::throw_str(msg);
@@ -51,8 +50,8 @@ pub fn scale_factor(window: &web_sys::Window) -> f64 {
     window.device_pixel_ratio()
 }
 
-fn fix_canvas_size(style: &CssStyleDeclaration, mut size: LogicalSize<f64>) -> LogicalSize<f64> {
-    if style.get_property_value("box-sizing").unwrap() == "border-box" {
+fn fix_canvas_size(style: &Style, mut size: LogicalSize<f64>) -> LogicalSize<f64> {
+    if style.get("box-sizing") == "border-box" {
         size.width += style_size_property(style, "border-left-width")
             + style_size_property(style, "border-right-width")
             + style_size_property(style, "padding-left")
@@ -69,76 +68,68 @@ fn fix_canvas_size(style: &CssStyleDeclaration, mut size: LogicalSize<f64>) -> L
 pub fn set_canvas_size(
     document: &Document,
     raw: &HtmlCanvasElement,
-    style: &CssStyleDeclaration,
+    style: &Style,
     new_size: LogicalSize<f64>,
 ) {
-    if !document.contains(Some(raw)) || style.get_property_value("display").unwrap() == "none" {
+    if !document.contains(Some(raw)) || style.get("display") == "none" {
         return;
     }
 
     let new_size = fix_canvas_size(style, new_size);
 
-    set_canvas_style_property(raw, "width", &format!("{}px", new_size.width));
-    set_canvas_style_property(raw, "height", &format!("{}px", new_size.height));
+    style.set("width", &format!("{}px", new_size.width));
+    style.set("height", &format!("{}px", new_size.height));
 }
 
 pub fn set_canvas_min_size(
     document: &Document,
     raw: &HtmlCanvasElement,
-    style: &CssStyleDeclaration,
+    style: &Style,
     dimensions: Option<LogicalSize<f64>>,
 ) {
     if let Some(dimensions) = dimensions {
-        if !document.contains(Some(raw)) || style.get_property_value("display").unwrap() == "none" {
+        if !document.contains(Some(raw)) || style.get("display") == "none" {
             return;
         }
 
         let new_size = fix_canvas_size(style, dimensions);
 
-        set_canvas_style_property(raw, "min-width", &format!("{}px", new_size.width));
-        set_canvas_style_property(raw, "min-height", &format!("{}px", new_size.height));
+        style.set("min-width", &format!("{}px", new_size.width));
+        style.set("min-height", &format!("{}px", new_size.height));
     } else {
-        style
-            .remove_property("min-width")
-            .expect("Property is read only");
-        style
-            .remove_property("min-height")
-            .expect("Property is read only");
+        style.remove("min-width");
+        style.remove("min-height");
     }
 }
 
 pub fn set_canvas_max_size(
     document: &Document,
     raw: &HtmlCanvasElement,
-    style: &CssStyleDeclaration,
+    style: &Style,
     dimensions: Option<LogicalSize<f64>>,
 ) {
     if let Some(dimensions) = dimensions {
-        if !document.contains(Some(raw)) || style.get_property_value("display").unwrap() == "none" {
+        if !document.contains(Some(raw)) || style.get("display") == "none" {
             return;
         }
 
         let new_size = fix_canvas_size(style, dimensions);
 
-        set_canvas_style_property(raw, "max-width", &format!("{}px", new_size.width));
-        set_canvas_style_property(raw, "max-height", &format!("{}px", new_size.height));
+        style.set("max-width", &format!("{}px", new_size.width));
+        style.set("max-height", &format!("{}px", new_size.height));
     } else {
-        style
-            .remove_property("max-width")
-            .expect("Property is read only");
-        style
-            .remove_property("max-height")
-            .expect("Property is read only");
+        style.remove("max-width");
+        style.remove("max-height");
     }
 }
 
 pub fn set_canvas_position(
     document: &Document,
     raw: &HtmlCanvasElement,
-    style: &CssStyleDeclaration,
+    style: &Style,
     mut position: LogicalPosition<f64>,
 ) {
-    if document.contains(Some(raw)) && style.get_property_value("display").unwrap() != "none" {
+    if document.contains(Some(raw)) && style.get("display") != "none" {
         position.x -= style_size_property(style, "margin-left")
             + style_size_property(style, "border-left-width")
             + style_size_property(style, "padding-left");
@@ -147,30 +138,21 @@ pub fn set_canvas_position(
             + style_size_property(style, "padding-top");
     }
 
-    set_canvas_style_property(raw, "position", "fixed");
-    set_canvas_style_property(raw, "left", &format!("{}px", position.x));
-    set_canvas_style_property(raw, "top", &format!("{}px", position.y));
+    style.set("position", "fixed");
+    style.set("left", &format!("{}px", position.x));
+    style.set("top", &format!("{}px", position.y));
 }
 
 /// This function will panic if the element is not inserted in the DOM
 /// or is not a CSS property that represents a size in pixel.
-pub fn style_size_property(style: &CssStyleDeclaration, property: &str) -> f64 {
-    let prop = style
-        .get_property_value(property)
-        .expect("Found invalid property");
+pub fn style_size_property(style: &Style, property: &str) -> f64 {
+    let prop = style.get(property);
     prop.strip_suffix("px")
         .expect("Element was not inserted into the DOM or is not a size in pixel")
         .parse()
         .expect("CSS property is not a size in pixel")
 }
 
-pub fn set_canvas_style_property(raw: &HtmlCanvasElement, property: &str, value: &str) {
-    let style = raw.style();
-    style
-        .set_property(property, value)
-        .unwrap_or_else(|err| panic!("error: {err:?}\nFailed to set {property}"))
-}
-
 pub fn is_dark_mode(window: &web_sys::Window) -> Option<bool> {
     window
         .match_media("(prefers-color-scheme: dark)")

src/platform_impl/web/web_sys/pointer.rs

@@ -80,7 +80,7 @@ impl PointerHandler {
         T: 'static + FnMut(ModifiersState, i32, PhysicalPosition<f64>, Force),
     {
         let window = canvas_common.window.clone();
-        self.on_pointer_release = Some(canvas_common.add_transient_event(
+        self.on_pointer_release = Some(canvas_common.add_event(
             "pointerup",
             move |event: PointerEvent| {
                 let modifiers = event::mouse_modifiers(&event);
@@ -118,7 +118,7 @@ impl PointerHandler {
     {
         let window = canvas_common.window.clone();
         let canvas = canvas_common.raw.clone();
-        self.on_pointer_press = Some(canvas_common.add_transient_event(
+        self.on_pointer_press = Some(canvas_common.add_event(
             "pointerdown",
             move |event: PointerEvent| {
                 if prevent_default {

src/platform_impl/web/web_sys/resize_scaling.rs

@@ -2,14 +2,14 @@ use js_sys::{Array, Object};
 use wasm_bindgen::prelude::{wasm_bindgen, Closure};
 use wasm_bindgen::{JsCast, JsValue};
 use web_sys::{
-    CssStyleDeclaration, Document, HtmlCanvasElement, MediaQueryList, ResizeObserver,
-    ResizeObserverBoxOptions, ResizeObserverEntry, ResizeObserverOptions, ResizeObserverSize,
-    Window,
+    Document, HtmlCanvasElement, MediaQueryList, ResizeObserver, ResizeObserverBoxOptions,
+    ResizeObserverEntry, ResizeObserverOptions, ResizeObserverSize, Window,
 };
 
 use crate::dpi::{LogicalSize, PhysicalSize};
 
 use super::super::backend;
+use super::canvas::Style;
 use super::media_query_handle::MediaQueryListHandle;
 
 use std::cell::{Cell, RefCell};
@@ -22,7 +22,7 @@ impl ResizeScaleHandle {
         window: Window,
         document: Document,
         canvas: HtmlCanvasElement,
-        style: CssStyleDeclaration,
+        style: Style,
         scale_handler: S,
         resize_handler: R,
     ) -> Self
@@ -51,7 +51,7 @@ struct ResizeScaleInternal {
     window: Window,
     document: Document,
     canvas: HtmlCanvasElement,
-    style: CssStyleDeclaration,
+    style: Style,
     mql: MediaQueryListHandle,
     observer: ResizeObserver,
     _observer_closure: Closure<dyn FnMut(Array, ResizeObserver)>,
@@ -65,7 +65,7 @@ impl ResizeScaleInternal {
         window: Window,
         document: Document,
         canvas: HtmlCanvasElement,
-        style: CssStyleDeclaration,
+        style: Style,
         scale_handler: S,
         resize_handler: R,
     ) -> Rc<RefCell<Self>>
@@ -152,9 +152,7 @@ impl ResizeScaleInternal {
     }
 
     fn notify(&mut self) {
-        if !self.document.contains(Some(&self.canvas))
-            || self.style.get_property_value("display").unwrap() == "none"
-        {
+        if !self.document.contains(Some(&self.canvas)) || self.style.get("display") == "none" {
             let size = PhysicalSize::new(0, 0);
 
             if self.notify_scale.replace(false) {
@@ -180,7 +178,7 @@ impl ResizeScaleInternal {
             backend::style_size_property(&self.style, "height"),
         );
 
-        if self.style.get_property_value("box-sizing").unwrap() == "border-box" {
+        if self.style.get("box-sizing") == "border-box" {
             size.width -= backend::style_size_property(&self.style, "border-left-width")
                 + backend::style_size_property(&self.style, "border-right-width")
                 + backend::style_size_property(&self.style, "padding-left")
@@ -246,10 +244,7 @@ impl ResizeScaleInternal {
             .get(0)
             .unchecked_into();
 
-        let writing_mode = self
-            .style
-            .get_property_value("writing-mode")
-            .expect("`writing-mode` is a valid CSS property");
+        let writing_mode = self.style.get("writing-mode");
 
         // means the canvas is not inserted into the DOM
         if writing_mode.is_empty() {

src/platform_impl/web/window.rs

@@ -1,3 +1,4 @@
+use crate::cursor::CustomCursor;
 use crate::dpi::{PhysicalPosition, PhysicalSize, Position, Size};
 use crate::error::{ExternalError, NotSupportedError, OsError as RootOE};
 use crate::icon::Icon;
@@ -7,12 +8,12 @@ use crate::window::{
 };
 use crate::SendSyncWrapper;
 
-use web_sys::HtmlCanvasElement;
-
+use super::cursor::SelectedCursor;
 use super::r#async::Dispatcher;
 use super::{backend, monitor::MonitorHandle, EventLoopWindowTarget, Fullscreen};
+use web_sys::HtmlCanvasElement;
 
-use std::cell::RefCell;
+use std::cell::{Cell, RefCell};
 use std::collections::VecDeque;
 use std::rc::Rc;
 
@@ -24,7 +25,8 @@ pub struct Inner {
     id: WindowId,
     pub window: web_sys::Window,
     canvas: Rc<RefCell<backend::Canvas>>,
-    previous_pointer: RefCell<&'static str>,
+    selected_cursor: RefCell<SelectedCursor>,
+    cursor_visible: Rc<Cell<bool>>,
     destroy_fn: Option<Box<dyn FnOnce()>>,
 }
 
@@ -53,7 +55,8 @@ impl Window {
             id,
             window: window.clone(),
             canvas,
-            previous_pointer: RefCell::new("auto"),
+            selected_cursor: Default::default(),
+            cursor_visible: Rc::new(Cell::new(true)),
             destroy_fn: Some(destroy_fn),
         };
 
@@ -195,8 +198,24 @@ impl Inner {
 
     #[inline]
     pub fn set_cursor_icon(&self, cursor: CursorIcon) {
-        *self.previous_pointer.borrow_mut() = cursor.name();
-        backend::set_canvas_style_property(self.canvas.borrow().raw(), "cursor", cursor.name());
+        *self.selected_cursor.borrow_mut() = SelectedCursor::Named(cursor);
+
+        if self.cursor_visible.get() {
+            self.canvas.borrow().style().set("cursor", cursor.name());
+        }
+    }
+
+    #[inline]
+    pub fn set_custom_cursor(&self, cursor: CustomCursor) {
+        let canvas = self.canvas.borrow();
+        let new_cursor = cursor.inner.build(
+            canvas.window(),
+            canvas.document(),
+            canvas.style(),
+            self.selected_cursor.take(),
+            self.cursor_visible.clone(),
+        );
+        *self.selected_cursor.borrow_mut() = new_cursor;
     }
 
     #[inline]
@@ -222,14 +241,14 @@ impl Inner {
 
     #[inline]
     pub fn set_cursor_visible(&self, visible: bool) {
-        if !visible {
-            backend::set_canvas_style_property(self.canvas.borrow().raw(), "cursor", "none");
-        } else {
-            backend::set_canvas_style_property(
-                self.canvas.borrow().raw(),
-                "cursor",
-                &self.previous_pointer.borrow(),
-            );
+        if !visible && self.cursor_visible.get() {
+            self.canvas.borrow().style().set("cursor", "none");
+            self.cursor_visible.set(false);
+        } else if visible && !self.cursor_visible.get() {
+            self.selected_cursor
+                .borrow()
+                .set_style(self.canvas.borrow().style());
+            self.cursor_visible.set(true);
         }
     }
 

src/platform_impl/windows/event_loop.rs

@@ -101,7 +101,7 @@ use runner::{EventLoopRunner, EventLoopRunnerShared};
 
 use self::runner::RunnerState;
 
-use super::window::set_skip_taskbar;
+use super::{window::set_skip_taskbar, SelectedCursor};
 
 type GetPointerFrameInfoHistory = unsafe extern "system" fn(
     pointerId: u32,
@@ -2011,16 +2011,21 @@ unsafe fn public_window_callback_inner<T: 'static>(
                 // `WM_MOUSEMOVE` seems to come after `WM_SETCURSOR` for a given cursor movement.
                 let in_client_area = super::loword(lparam as u32) as u32 == HTCLIENT;
                 if in_client_area {
-                    Some(window_state.mouse.cursor)
+                    Some(window_state.mouse.selected_cursor.clone())
                 } else {
                     None
                 }
             };
 
             match set_cursor_to {
-                Some(cursor) => {
-                    let cursor = unsafe { LoadCursorW(0, util::to_windows_cursor(cursor)) };
-                    unsafe { SetCursor(cursor) };
+                Some(selected_cursor) => {
+                    let hcursor = match selected_cursor {
+                        SelectedCursor::Named(cursor_icon) => unsafe {
+                            LoadCursorW(0, util::to_windows_cursor(cursor_icon))
+                        },
+                        SelectedCursor::Custom(cursor) => cursor.as_raw_handle(),
+                    };
+                    unsafe { SetCursor(hcursor) };
                     result = ProcResult::Value(0);
                 }
                 None => result = ProcResult::DefWindowProc(wparam),

src/platform_impl/windows/icon.rs

@@ -1,18 +1,23 @@
-use std::{fmt, io, mem, path::Path, sync::Arc};
+use std::{ffi::c_void, fmt, io, mem, path::Path, sync::Arc};
 
+use cursor_icon::CursorIcon;
 use windows_sys::{
     core::PCWSTR,
     Win32::{
         Foundation::HWND,
+        Graphics::Gdi::{
+            CreateBitmap, CreateCompatibleBitmap, DeleteObject, GetDC, ReleaseDC, SetBitmapBits,
+        },
         UI::WindowsAndMessaging::{
-            CreateIcon, DestroyIcon, LoadImageW, SendMessageW, HICON, ICON_BIG, ICON_SMALL,
-            IMAGE_ICON, LR_DEFAULTSIZE, LR_LOADFROMFILE, WM_SETICON,
+            CreateIcon, CreateIconIndirect, DestroyCursor, DestroyIcon, LoadImageW, SendMessageW,
+            HCURSOR, HICON, ICONINFO, ICON_BIG, ICON_SMALL, IMAGE_ICON, LR_DEFAULTSIZE,
+            LR_LOADFROMFILE, WM_SETICON,
         },
     },
 };
 
-use crate::dpi::PhysicalSize;
 use crate::icon::*;
+use crate::{cursor::CursorImage, dpi::PhysicalSize};
 
 use super::util;
 
@@ -160,3 +165,92 @@ pub fn unset_for_window(hwnd: HWND, icon_type: IconType) {
         SendMessageW(hwnd, WM_SETICON, icon_type as usize, 0);
     }
 }
+
+#[derive(Debug, Clone)]
+pub enum SelectedCursor {
+    Named(CursorIcon),
+    Custom(WinCursor),
+}
+
+impl Default for SelectedCursor {
+    fn default() -> Self {
+        Self::Named(Default::default())
+    }
+}
+
+#[derive(Clone, Debug)]
+pub struct WinCursor {
+    inner: Arc<RaiiCursor>,
+}
+
+impl WinCursor {
+    pub fn as_raw_handle(&self) -> HICON {
+        self.inner.handle
+    }
+
+    fn from_handle(handle: HCURSOR) -> Self {
+        Self {
+            inner: Arc::new(RaiiCursor { handle }),
+        }
+    }
+
+    pub fn new(image: &CursorImage) -> Result<Self, io::Error> {
+        let mut bgra = image.rgba.clone();
+        bgra.chunks_exact_mut(4).for_each(|chunk| chunk.swap(0, 2));
+
+        let w = image.width as i32;
+        let h = image.height as i32;
+
+        unsafe {
+            let hdc_screen = GetDC(0);
+            if hdc_screen == 0 {
+                return Err(io::Error::last_os_error());
+            }
+            let hbm_color = CreateCompatibleBitmap(hdc_screen, w, h);
+            ReleaseDC(0, hdc_screen);
+            if hbm_color == 0 {
+                return Err(io::Error::last_os_error());
+            }
+            if SetBitmapBits(hbm_color, bgra.len() as u32, bgra.as_ptr() as *const c_void) == 0 {
+                DeleteObject(hbm_color);
+                return Err(io::Error::last_os_error());
+            };
+
+            // Mask created according to https://learn.microsoft.com/en-us/windows/win32/api/wingdi/nf-wingdi-createbitmap#parameters
+            let mask_bits: Vec<u8> = vec![0xff; ((((w + 15) >> 4) << 1) * h) as usize];
+            let hbm_mask = CreateBitmap(w, h, 1, 1, mask_bits.as_ptr() as *const _);
+            if hbm_mask == 0 {
+                DeleteObject(hbm_color);
+                return Err(io::Error::last_os_error());
+            }
+
+            let icon_info = ICONINFO {
+                fIcon: 0,
+                xHotspot: image.hotspot_x as u32,
+                yHotspot: image.hotspot_y as u32,
+                hbmMask: hbm_mask,
+                hbmColor: hbm_color,
+            };
+
+            let handle = CreateIconIndirect(&icon_info as *const _);
+            DeleteObject(hbm_color);
+            DeleteObject(hbm_mask);
+            if handle == 0 {
+                return Err(io::Error::last_os_error());
+            }
+
+            Ok(Self::from_handle(handle))
+        }
+    }
+}
+
+#[derive(Debug)]
+struct RaiiCursor {
+    handle: HCURSOR,
+}
+
+impl Drop for RaiiCursor {
+    fn drop(&mut self) {
+        unsafe { DestroyCursor(self.handle) };
+    }
+}

src/platform_impl/windows/ime.rs

@@ -10,9 +10,9 @@ use windows_sys::Win32::{
     UI::{
         Input::Ime::{
             ImmAssociateContextEx, ImmGetCompositionStringW, ImmGetContext, ImmReleaseContext,
-            ImmSetCandidateWindow, ImmSetCompositionWindow, ATTR_TARGET_CONVERTED,
-            ATTR_TARGET_NOTCONVERTED, CANDIDATEFORM, CFS_EXCLUDE, CFS_POINT, COMPOSITIONFORM,
-            GCS_COMPATTR, GCS_COMPSTR, GCS_CURSORPOS, GCS_RESULTSTR, IACE_CHILDREN, IACE_DEFAULT,
+            ImmSetCandidateWindow, ATTR_TARGET_CONVERTED, ATTR_TARGET_NOTCONVERTED, CANDIDATEFORM,
+            CFS_EXCLUDE, GCS_COMPATTR, GCS_COMPSTR, GCS_CURSORPOS, GCS_RESULTSTR, IACE_CHILDREN,
+            IACE_DEFAULT,
         },
         WindowsAndMessaging::{GetSystemMetrics, SM_IMMENABLED},
     },
@@ -124,7 +124,7 @@ impl ImeContext {
             left: x,
             top: y,
             right: x + width,
-            bottom: y + height,
+            bottom: y - height,
         };
         let candidate_form = CANDIDATEFORM {
             dwIndex: 0,
@@ -132,16 +132,8 @@ impl ImeContext {
             ptCurrentPos: POINT { x, y },
             rcArea: rc_area,
         };
-        let composition_form = COMPOSITIONFORM {
-            dwStyle: CFS_POINT,
-            ptCurrentPos: POINT { x, y: y + height },
-            rcArea: rc_area,
-        };
 
-        unsafe {
-            ImmSetCompositionWindow(self.himc, &composition_form);
-            ImmSetCandidateWindow(self.himc, &candidate_form);
-        }
+        unsafe { ImmSetCandidateWindow(self.himc, &candidate_form) };
     }
 
     pub unsafe fn set_ime_allowed(hwnd: HWND, allowed: bool) {

src/platform_impl/windows/mod.rs

@@ -10,12 +10,13 @@ pub(crate) use self::{
     event_loop::{
         EventLoop, EventLoopProxy, EventLoopWindowTarget, PlatformSpecificEventLoopAttributes,
     },
-    icon::WinIcon,
+    icon::{SelectedCursor, WinIcon},
     monitor::{MonitorHandle, VideoMode},
     window::Window,
 };
 
 pub use self::icon::WinIcon as PlatformIcon;
+pub(crate) use crate::cursor::CursorImage as PlatformCustomCursor;
 use crate::platform_impl::Fullscreen;
 
 use crate::event::DeviceId as RootDeviceId;

src/platform_impl/windows/window.rs

@@ -55,6 +55,7 @@ use windows_sys::Win32::{
 };
 
 use crate::{
+    cursor::CustomCursor,
     dpi::{PhysicalPosition, PhysicalSize, Position, Size},
     error::{ExternalError, NotSupportedError, OsError as RootOsError},
     icon::Icon,
@@ -66,13 +67,13 @@ use crate::{
         dpi::{dpi_to_scale_factor, enable_non_client_dpi_scaling, hwnd_dpi},
         drop_handler::FileDropHandler,
         event_loop::{self, EventLoopWindowTarget, DESTROY_MSG_ID},
-        icon::{self, IconType},
+        icon::{self, IconType, WinCursor},
         ime::ImeContext,
         keyboard::KeyEventBuilder,
         monitor::{self, MonitorHandle},
         util,
         window_state::{CursorFlags, SavedWindow, WindowFlags, WindowState},
-        Fullscreen, PlatformSpecificWindowBuilderAttributes, WindowId,
+        Fullscreen, PlatformSpecificWindowBuilderAttributes, SelectedCursor, WindowId,
     },
     window::{
         CursorGrabMode, CursorIcon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
@@ -396,13 +397,28 @@ impl Window {
 
     #[inline]
     pub fn set_cursor_icon(&self, cursor: CursorIcon) {
-        self.window_state_lock().mouse.cursor = cursor;
+        self.window_state_lock().mouse.selected_cursor = SelectedCursor::Named(cursor);
         self.thread_executor.execute_in_thread(move || unsafe {
             let cursor = LoadCursorW(0, util::to_windows_cursor(cursor));
             SetCursor(cursor);
         });
     }
 
+    #[inline]
+    pub fn set_custom_cursor(&self, cursor: CustomCursor) {
+        let new_cursor = match WinCursor::new(&cursor.inner) {
+            Ok(cursor) => cursor,
+            Err(err) => {
+                warn!("Failed to create custom cursor: {err}");
+                return;
+            }
+        };
+        self.window_state_lock().mouse.selected_cursor = SelectedCursor::Custom(new_cursor.clone());
+        self.thread_executor.execute_in_thread(move || unsafe {
+            SetCursor(new_cursor.as_raw_handle());
+        });
+    }
+
     #[inline]
     pub fn set_cursor_grab(&self, mode: CursorGrabMode) -> Result<(), ExternalError> {
         let confine = match mode {

src/platform_impl/windows/window_state.rs

@@ -2,8 +2,8 @@ use crate::{
     dpi::{PhysicalPosition, PhysicalSize, Size},
     icon::Icon,
     keyboard::ModifiersState,
-    platform_impl::platform::{event_loop, util, Fullscreen},
-    window::{CursorIcon, Theme, WindowAttributes},
+    platform_impl::platform::{event_loop, util, Fullscreen, SelectedCursor},
+    window::{Theme, WindowAttributes},
 };
 use std::io;
 use std::sync::MutexGuard;
@@ -67,7 +67,7 @@ pub struct SavedWindow {
 
 #[derive(Clone)]
 pub struct MouseProperties {
-    pub cursor: CursorIcon,
+    pub(crate) selected_cursor: SelectedCursor,
     pub capture_count: u32,
     cursor_flags: CursorFlags,
     pub last_position: Option<PhysicalPosition<f64>>,
@@ -143,7 +143,7 @@ impl WindowState {
     ) -> WindowState {
         WindowState {
             mouse: MouseProperties {
-                cursor: CursorIcon::default(),
+                selected_cursor: SelectedCursor::default(),
                 capture_count: 0,
                 cursor_flags: CursorFlags::empty(),
                 last_position: None,

src/window.rs

@@ -9,6 +9,7 @@ use crate::{
     platform_impl, SendSyncWrapper,
 };
 
+pub use crate::cursor::{BadImage, CustomCursor, MAX_CURSOR_SIZE};
 pub use crate::icon::{BadIcon, Icon};
 
 #[doc(inline)]
@@ -1077,8 +1078,7 @@ impl Window {
     /// - **Wayland:** Does not support exclusive fullscreen mode and will no-op a request.
     /// - **Windows:** Screen saver is disabled in fullscreen mode.
     /// - **Android / Orbital:** Unsupported.
-    /// - **Web:** Does nothing without a [transient activation], but queues the request
-    ///   for the next activation.
+    /// - **Web:** Does nothing without a [transient activation].
     ///
     /// [transient activation]: https://developer.mozilla.org/en-US/docs/Glossary/Transient_activation
     #[inline]
@@ -1336,6 +1336,7 @@ impl Window {
 /// Cursor functions.
 impl Window {
     /// Modifies the cursor icon of the window.
+    /// Overwrites cursors set in [`Window::set_custom_cursor`].
     ///
     /// ## Platform-specific
     ///
@@ -1346,6 +1347,19 @@ impl Window {
             .maybe_queue_on_main(move |w| w.set_cursor_icon(cursor))
     }
 
+    /// Modifies the cursor icon of the window with a custom cursor.
+    /// Overwrites cursors set in [`Window::set_cursor_icon`].
+    ///
+    /// ## Platform-specific
+    ///
+    /// - **iOS / Android / Orbital:** Unsupported.
+    #[inline]
+    pub fn set_custom_cursor(&self, cursor: &CustomCursor) {
+        let cursor = cursor.clone();
+        self.window
+            .maybe_queue_on_main(move |w| w.set_custom_cursor(cursor))
+    }
+
     /// Changes the position of the cursor in window coordinates.
     ///
     /// ```no_run

tests/send_objects.rs

@@ -28,3 +28,8 @@ fn ids_send() {
     needs_send::<winit::event::DeviceId>();
     needs_send::<winit::monitor::MonitorHandle>();
 }
+
+#[test]
+fn custom_cursor_send() {
+    needs_send::<winit::window::CustomCursor>();
+}

tests/sync_object.rs

@@ -11,3 +11,8 @@ fn window_sync() {
 fn window_builder_sync() {
     needs_sync::<winit::window::WindowBuilder>();
 }
+
+#[test]
+fn custom_cursor_sync() {
+    needs_sync::<winit::window::CustomCursor>();
+}