Custom cursor improvements (#3292)

src/platform_impl/web/cursor.rs

@@ -1,6 +1,8 @@
 use std::{
     cell::RefCell,
-    future, mem,
+    future,
+    hash::{Hash, Hasher},
+    mem,
     ops::DerefMut,
     rc::{self, Rc},
     sync::{self, Arc},
@@ -25,7 +27,7 @@ use self::thread_safe::ThreadSafe;
 use super::{backend::Style, r#async::AsyncSender, EventLoopWindowTarget};
 
 #[derive(Debug)]
-pub enum CustomCursorBuilder {
+pub(crate) enum CustomCursorBuilder {
     Image(CursorImage),
     Url {
         url: String,
@@ -35,35 +37,6 @@ pub enum CustomCursorBuilder {
 }
 
 impl CustomCursorBuilder {
-    pub fn build<T>(self, window_target: &EventLoopWindowTarget<T>) -> Arc<CustomCursor> {
-        Lazy::force(&DROP_HANDLER);
-
-        match self {
-            Self::Image(image) => ImageState::from_rgba(
-                window_target.runner.window(),
-                window_target.runner.document().clone(),
-                &image,
-            ),
-            Self::Url {
-                url,
-                hotspot_x,
-                hotspot_y,
-            } => ImageState::from_url(url, hotspot_x, hotspot_y),
-        }
-    }
-}
-
-#[derive(Debug)]
-pub struct CustomCursor(Option<ThreadSafe<RefCell<ImageState>>>);
-
-static DROP_HANDLER: Lazy<AsyncSender<ThreadSafe<RefCell<ImageState>>>> = Lazy::new(|| {
-    let (sender, receiver) = r#async::channel();
-    wasm_bindgen_futures::spawn_local(async move { while receiver.next().await.is_ok() {} });
-
-    sender
-});
-
-impl CustomCursor {
     pub fn from_rgba(
         rgba: Vec<u8>,
         width: u16,
@@ -75,9 +48,60 @@ impl CustomCursor {
             rgba, width, height, hotspot_x, hotspot_y,
         )?))
     }
+}
 
+#[derive(Clone, Debug)]
+pub struct CustomCursor(Arc<Inner>);
+
+impl Hash for CustomCursor {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        Arc::as_ptr(&self.0).hash(state);
+    }
+}
+
+impl PartialEq for CustomCursor {
+    fn eq(&self, other: &Self) -> bool {
+        Arc::ptr_eq(&self.0, &other.0)
+    }
+}
+
+impl Eq for CustomCursor {}
+
+impl CustomCursor {
+    pub(crate) fn build<T>(
+        builder: CustomCursorBuilder,
+        window_target: &EventLoopWindowTarget<T>,
+    ) -> Self {
+        Lazy::force(&DROP_HANDLER);
+
+        Self(match builder {
+            CustomCursorBuilder::Image(image) => ImageState::from_rgba(
+                window_target.runner.window(),
+                window_target.runner.document().clone(),
+                &image,
+            ),
+            CustomCursorBuilder::Url {
+                url,
+                hotspot_x,
+                hotspot_y,
+            } => ImageState::from_url(url, hotspot_x, hotspot_y),
+        })
+    }
+}
+
+#[derive(Debug)]
+struct Inner(Option<ThreadSafe<RefCell<ImageState>>>);
+
+static DROP_HANDLER: Lazy<AsyncSender<ThreadSafe<RefCell<ImageState>>>> = Lazy::new(|| {
+    let (sender, receiver) = r#async::channel();
+    wasm_bindgen_futures::spawn_local(async move { while receiver.next().await.is_ok() {} });
+
+    sender
+});
+
+impl Inner {
     fn new() -> Arc<Self> {
-        Arc::new(Self(Some(ThreadSafe::new(RefCell::new(
+        Arc::new(Inner(Some(ThreadSafe::new(RefCell::new(
             ImageState::Loading(None),
         )))))
     }
@@ -90,7 +114,7 @@ impl CustomCursor {
     }
 }
 
-impl Drop for CustomCursor {
+impl Drop for Inner {
     fn drop(&mut self) {
         let value = self
             .0
@@ -130,13 +154,13 @@ impl CursorState {
         this.set_style();
     }
 
-    pub fn set_custom_cursor(&self, cursor: Arc<CustomCursor>) {
+    pub(crate) fn set_custom_cursor(&self, cursor: CustomCursor) {
         let mut this = self.0.borrow_mut();
 
-        match cursor.get().borrow_mut().deref_mut() {
+        match cursor.0.get().borrow_mut().deref_mut() {
             ImageState::Loading(state) => {
                 this.cursor = SelectedCursor::ImageLoading {
-                    state: cursor.clone(),
+                    state: cursor.0.clone(),
                     previous: mem::take(&mut this.cursor).into(),
                 };
                 *state = Some(Rc::downgrade(&self.0));
@@ -187,7 +211,7 @@ impl State {
 enum SelectedCursor {
     Named(CursorIcon),
     ImageLoading {
-        state: Arc<CustomCursor>,
+        state: Arc<Inner>,
         previous: Previous,
     },
     ImageReady(Rc<Image>),
@@ -241,7 +265,7 @@ enum ImageState {
 }
 
 impl ImageState {
-    fn from_rgba(window: &Window, document: Document, image: &CursorImage) -> Arc<CustomCursor> {
+    fn from_rgba(window: &Window, document: Document, image: &CursorImage) -> Arc<Inner> {
         // 1. Create an `ImageData` from the RGBA data.
         // 2. Create an `ImageBitmap` from the `ImageData`.
         // 3. Draw `ImageBitmap` on an `HTMLCanvasElement`.
@@ -293,7 +317,7 @@ impl ImageState {
                 .expect("unexpected exception in `createImageBitmap()`"),
         );
 
-        let this = CustomCursor::new();
+        let this = Inner::new();
 
         wasm_bindgen_futures::spawn_local({
             let weak = Arc::downgrade(&this);
@@ -406,8 +430,8 @@ impl ImageState {
         this
     }
 
-    fn from_url(url: String, hotspot_x: u16, hotspot_y: u16) -> Arc<CustomCursor> {
-        let this = CustomCursor::new();
+    fn from_url(url: String, hotspot_x: u16, hotspot_y: u16) -> Arc<Inner> {
+        let this = Inner::new();
         wasm_bindgen_futures::spawn_local(Self::decode(
             Arc::downgrade(&this),
             url,
@@ -420,7 +444,7 @@ impl ImageState {
     }
 
     async fn decode(
-        weak: sync::Weak<CustomCursor>,
+        weak: sync::Weak<Inner>,
         url: String,
         object: bool,
         hotspot_x: u16,

src/platform_impl/web/window.rs

@@ -16,7 +16,6 @@ use web_sys::HtmlCanvasElement;
 use std::cell::RefCell;
 use std::collections::VecDeque;
 use std::rc::Rc;
-use std::sync::Arc;
 
 pub struct Window {
     inner: Dispatcher<Inner>,
@@ -218,7 +217,7 @@ impl Inner {
     }
 
     #[inline]
-    pub(crate) fn set_custom_cursor(&self, cursor: Arc<PlatformCustomCursor>) {
+    pub(crate) fn set_custom_cursor(&self, cursor: PlatformCustomCursor) {
         self.cursor.set_custom_cursor(cursor)
     }