Inverse bevy_render bevy_winit dependency and move cursor to bevy_winit (#15649)

# Objective

- `bevy_render` should not depend on `bevy_winit`
- Fixes #15565

## Solution

- `bevy_render` no longer depends on `bevy_winit`
- The following is behind the `custom_cursor` feature
- Move custom cursor code from `bevy_render` to `bevy_winit` behind the
`custom_cursor` feature
- `bevy_winit` now depends on `bevy_render` (for `Image` and
`TextureFormat`)
- `bevy_winit` now depends on `bevy_asset` (for `Assets`, `Handle` and
`AssetId`)
  - `bevy_winit` now depends on `bytemuck` (already in tree)
- Custom cursor code in `bevy_winit` reworked to use `AssetId` (other
than that it is taken over 1:1)
- Rework `bevy_winit` custom cursor interface visibility now that the
logic is all contained in `bevy_winit`

## Testing

- I ran the screenshot and window_settings examples
- Tested on linux wayland so far

---

## Migration Guide

`CursorIcon` and `CustomCursor` previously provided by
`bevy::render::view::cursor` is now available from `bevy::winit`.
A new feature `custom_cursor` enables this functionality (default
feature).

Cargo.toml

@@ -132,6 +132,7 @@ default = [
   "webgl2",
   "sysinfo_plugin",
   "android-game-activity",
+  "custom_cursor",
 ]
 
 # Provides an implementation for picking sprites
@@ -417,6 +418,9 @@ track_change_detection = ["bevy_internal/track_change_detection"]
 # Enable function reflection
 reflect_functions = ["bevy_internal/reflect_functions"]
 
+# Enable winit custom cursor support
+custom_cursor = ["bevy_internal/custom_cursor"]
+
 [dependencies]
 bevy_internal = { path = "crates/bevy_internal", version = "0.15.0-dev", default-features = false }
 

crates/bevy_internal/Cargo.toml

@@ -223,6 +223,9 @@ reflect_functions = [
   "bevy_ecs/reflect_functions",
 ]
 
+# Enable winit custom cursor support
+custom_cursor = ["bevy_winit/custom_cursor"]
+
 [dependencies]
 # bevy
 bevy_a11y = { path = "../bevy_a11y", version = "0.15.0-dev" }

crates/bevy_render/Cargo.toml

@@ -66,7 +66,6 @@ bevy_render_macros = { path = "macros", version = "0.15.0-dev" }
 bevy_time = { path = "../bevy_time", version = "0.15.0-dev" }
 bevy_transform = { path = "../bevy_transform", version = "0.15.0-dev" }
 bevy_window = { path = "../bevy_window", version = "0.15.0-dev" }
-bevy_winit = { path = "../bevy_winit", version = "0.15.0-dev" }
 bevy_utils = { path = "../bevy_utils", version = "0.15.0-dev" }
 bevy_tasks = { path = "../bevy_tasks", version = "0.15.0-dev" }
 bevy_image = { path = "../bevy_image", version = "0.15.0-dev" }

crates/bevy_render/src/view/window/mod.rs

@@ -15,12 +15,10 @@ use core::{
     num::NonZero,
     ops::{Deref, DerefMut},
 };
-use cursor::CursorPlugin;
 use wgpu::{
     SurfaceConfiguration, SurfaceTargetUnsafe, TextureFormat, TextureUsages, TextureViewDescriptor,
 };
 
-pub mod cursor;
 pub mod screenshot;
 
 use screenshot::{ScreenshotPlugin, ScreenshotToScreenPipeline};
@@ -29,7 +27,7 @@ pub struct WindowRenderPlugin;
 
 impl Plugin for WindowRenderPlugin {
     fn build(&self, app: &mut App) {
-        app.add_plugins((ScreenshotPlugin, CursorPlugin));
+        app.add_plugins(ScreenshotPlugin);
 
         if let Some(render_app) = app.get_sub_app_mut(RenderApp) {
             render_app

crates/bevy_winit/Cargo.toml

@@ -18,6 +18,8 @@ serialize = ["serde", "bevy_input/serialize", "bevy_window/serialize"]
 android-native-activity = ["winit/android-native-activity"]
 android-game-activity = ["winit/android-game-activity"]
 
+custom_cursor = ["bevy_image", "bevy_asset", "bytemuck", "wgpu-types"]
+
 
 [dependencies]
 # bevy
@@ -34,6 +36,10 @@ bevy_window = { path = "../bevy_window", version = "0.15.0-dev" }
 bevy_utils = { path = "../bevy_utils", version = "0.15.0-dev" }
 bevy_tasks = { path = "../bevy_tasks", version = "0.15.0-dev" }
 
+# bevy optional
+bevy_asset = { path = "../bevy_asset", version = "0.15.0-dev", optional = true }
+bevy_image = { path = "../bevy_image", version = "0.15.0-dev", optional = true }
+
 # other
 # feature rwh_06 refers to window_raw_handle@v0.6
 winit = { version = "0.30", default-features = false, features = ["rwh_06"] }
@@ -44,6 +50,8 @@ approx = { version = "0.5", default-features = false }
 cfg-if = "1.0"
 raw-window-handle = "0.6"
 serde = { version = "1.0", features = ["derive"], optional = true }
+bytemuck = { version = "1.5", optional = true }
+wgpu-types = { version = "22", optional = true }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 wasm-bindgen = { version = "0.2" }

crates/bevy_winit/src/converters.rs

@@ -6,7 +6,9 @@ use bevy_input::{
     ButtonState,
 };
 use bevy_math::Vec2;
-use bevy_window::{EnabledButtons, SystemCursorIcon, WindowLevel, WindowTheme};
+#[cfg(feature = "custom_cursor")]
+use bevy_window::SystemCursorIcon;
+use bevy_window::{EnabledButtons, WindowLevel, WindowTheme};
 use winit::keyboard::{Key, NamedKey, NativeKey};
 
 pub fn convert_keyboard_input(
@@ -628,6 +630,7 @@ pub fn convert_native_key(native_key: &NativeKey) -> bevy_input::keyboard::Nativ
     }
 }
 
+#[cfg(feature = "custom_cursor")]
 /// Converts a [`SystemCursorIcon`] to a [`winit::window::CursorIcon`].
 pub fn convert_system_cursor_icon(cursor_icon: SystemCursorIcon) -> winit::window::CursorIcon {
     match cursor_icon {

crates/bevy_winit/src/cursor.rs

@@ -1,5 +1,12 @@
+//! Components to customize winit cursor
+
+use crate::{
+    converters::convert_system_cursor_icon,
+    state::{CursorSource, CustomCursorCache, CustomCursorCacheKey, PendingCursor},
+    WinitCustomCursor,
+};
 use bevy_app::{App, Last, Plugin};
-use bevy_asset::{AssetId, Assets, Handle};
+use bevy_asset::{Assets, Handle};
 use bevy_ecs::{
     change_detection::DetectChanges,
     component::Component,
@@ -10,18 +17,13 @@ use bevy_ecs::{
     system::{Commands, Local, Query, Res},
     world::{OnRemove, Ref},
 };
+use bevy_image::Image;
 use bevy_reflect::{std_traits::ReflectDefault, Reflect};
 use bevy_utils::{tracing::warn, HashSet};
 use bevy_window::{SystemCursorIcon, Window};
-use bevy_winit::{
-    convert_system_cursor_icon, CursorSource, CustomCursorCache, CustomCursorCacheKey,
-    PendingCursor,
-};
-use wgpu::TextureFormat;
+use wgpu_types::TextureFormat;
 
-use crate::prelude::Image;
-
-pub struct CursorPlugin;
+pub(crate) struct CursorPlugin;
 
 impl Plugin for CursorPlugin {
     fn build(&self, app: &mut App) {
@@ -85,7 +87,7 @@ pub enum CustomCursor {
     },
 }
 
-pub fn update_cursors(
+fn update_cursors(
     mut commands: Commands,
     windows: Query<(Entity, Ref<CursorIcon>), With<Window>>,
     cursor_cache: Res<CustomCursorCache>,
@@ -99,12 +101,7 @@ pub fn update_cursors(
 
         let cursor_source = match cursor.as_ref() {
             CursorIcon::Custom(CustomCursor::Image { handle, hotspot }) => {
-                let cache_key = match handle.id() {
-                    AssetId::Index { index, .. } => {
-                        CustomCursorCacheKey::AssetIndex(index.to_bits())
-                    }
-                    AssetId::Uuid { uuid } => CustomCursorCacheKey::AssetUuid(uuid.as_u128()),
-                };
+                let cache_key = CustomCursorCacheKey::Asset(handle.id());
 
                 if cursor_cache.0.contains_key(&cache_key) {
                     CursorSource::CustomCached(cache_key)
@@ -123,7 +120,7 @@ pub fn update_cursors(
 
                     let width = image.texture_descriptor.size.width;
                     let height = image.texture_descriptor.size.height;
-                    let source = match bevy_winit::WinitCustomCursor::from_rgba(
+                    let source = match WinitCustomCursor::from_rgba(
                         rgba,
                         width as u16,
                         height as u16,
@@ -147,9 +144,8 @@ pub fn update_cursors(
                 if cursor_cache.0.contains_key(&cache_key) {
                     CursorSource::CustomCached(cache_key)
                 } else {
-                    use bevy_winit::CustomCursorExtWebSys;
-                    let source =
-                        bevy_winit::WinitCustomCursor::from_url(url.clone(), hotspot.0, hotspot.1);
+                    use crate::CustomCursorExtWebSys;
+                    let source = WinitCustomCursor::from_url(url.clone(), hotspot.0, hotspot.1);
                     CursorSource::Custom((cache_key, source))
                 }
             }
@@ -165,7 +161,7 @@ pub fn update_cursors(
 }
 
 /// Resets the cursor to the default icon when `CursorIcon` is removed.
-pub fn on_remove_cursor_icon(trigger: Trigger<OnRemove, CursorIcon>, mut commands: Commands) {
+fn on_remove_cursor_icon(trigger: Trigger<OnRemove, CursorIcon>, mut commands: Commands) {
     // Use `try_insert` to avoid panic if the window is being destroyed.
     commands
         .entity(trigger.entity())

crates/bevy_winit/src/lib.rs

@@ -23,8 +23,6 @@ use bevy_a11y::AccessibilityRequested;
 use bevy_app::{App, Last, Plugin};
 use bevy_ecs::prelude::*;
 use bevy_window::{exit_on_all_closed, Window, WindowCreated};
-pub use converters::convert_system_cursor_icon;
-pub use state::{CursorSource, CustomCursorCache, CustomCursorCacheKey, PendingCursor};
 use system::{changed_windows, check_keyboard_focus_lost, despawn_windows};
 pub use system::{create_monitors, create_windows};
 #[cfg(all(target_family = "wasm", target_os = "unknown"))]
@@ -44,6 +42,8 @@ use crate::{
 
 pub mod accessibility;
 mod converters;
+#[cfg(feature = "custom_cursor")]
+pub mod cursor;
 mod state;
 mod system;
 mod winit_config;
@@ -131,6 +131,8 @@ impl<T: Event> Plugin for WinitPlugin<T> {
             );
 
         app.add_plugins(AccessKitPlugin);
+        #[cfg(feature = "custom_cursor")]
+        app.add_plugins(cursor::CursorPlugin);
 
         let event_loop = event_loop_builder
             .build()

crates/bevy_winit/src/state.rs

@@ -1,5 +1,7 @@
 use approx::relative_eq;
 use bevy_app::{App, AppExit, PluginsState};
+#[cfg(feature = "custom_cursor")]
+use bevy_asset::AssetId;
 use bevy_ecs::{
     change_detection::{DetectChanges, NonSendMut, Res},
     entity::Entity,
@@ -8,6 +10,8 @@ use bevy_ecs::{
     system::SystemState,
     world::FromWorld,
 };
+#[cfg(feature = "custom_cursor")]
+use bevy_image::Image;
 use bevy_input::{
     gestures::*,
     mouse::{MouseButtonInput, MouseMotion, MouseScrollUnit, MouseWheel},
@@ -16,7 +20,9 @@ use bevy_log::{error, trace, warn};
 use bevy_math::{ivec2, DVec2, Vec2};
 #[cfg(not(target_arch = "wasm32"))]
 use bevy_tasks::tick_global_task_pools_on_main_thread;
-use bevy_utils::{HashMap, Instant};
+#[cfg(feature = "custom_cursor")]
+use bevy_utils::HashMap;
+use bevy_utils::Instant;
 use core::marker::PhantomData;
 use winit::{
     application::ApplicationHandler,
@@ -88,6 +94,7 @@ struct WinitAppRunnerState<T: Event> {
 
 impl<T: Event> WinitAppRunnerState<T> {
     fn new(mut app: App) -> Self {
+        #[cfg(feature = "custom_cursor")]
         app.add_event::<T>().init_resource::<CustomCursorCache>();
 
         let event_writer_system_state: SystemState<(
@@ -134,23 +141,25 @@ impl<T: Event> WinitAppRunnerState<T> {
     }
 }
 
+#[cfg(feature = "custom_cursor")]
 /// Identifiers for custom cursors used in caching.
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
 pub enum CustomCursorCacheKey {
-    /// u64 is used instead of `AssetId`, because `bevy_asset` can't be imported here.
-    AssetIndex(u64),
-    /// u128 is used instead of `AssetId`, because `bevy_asset` can't be imported here.
-    AssetUuid(u128),
-    /// A URL to a cursor.
+    /// An `AssetId` to a cursor.
+    Asset(AssetId<Image>),
+    #[cfg(all(target_family = "wasm", target_os = "unknown"))]
+    /// An URL to a cursor.
     Url(String),
 }
 
+#[cfg(feature = "custom_cursor")]
 /// Caches custom cursors. On many platforms, creating custom cursors is expensive, especially on
 /// the web.
 #[derive(Debug, Clone, Default, Resource)]
 pub struct CustomCursorCache(pub HashMap<CustomCursorCacheKey, winit::window::CustomCursor>);
 
-/// A source for a cursor. Is created in `bevy_render` and consumed by the winit event loop.
+#[cfg(feature = "custom_cursor")]
+/// A source for a cursor. Consumed by the winit event loop.
 #[derive(Debug)]
 pub enum CursorSource {
     /// A custom cursor was identified to be cached, no reason to recreate it.
@@ -161,6 +170,7 @@ pub enum CursorSource {
     System(winit::window::CursorIcon),
 }
 
+#[cfg(feature = "custom_cursor")]
 /// Component that indicates what cursor should be used for a window. Inserted
 /// automatically after changing `CursorIcon` and consumed by the winit event
 /// loop.
@@ -547,6 +557,7 @@ impl<T: Event> ApplicationHandler<T> for WinitAppRunnerState<T> {
             // This is a temporary solution, full solution is mentioned here: https://github.com/bevyengine/bevy/issues/1343#issuecomment-770091684
             if !self.ran_update_since_last_redraw || all_invisible {
                 self.run_app_update();
+                #[cfg(feature = "custom_cursor")]
                 self.update_cursors(event_loop);
                 self.ran_update_since_last_redraw = true;
             } else {
@@ -775,6 +786,7 @@ impl<T: Event> WinitAppRunnerState<T> {
             .send_batch(buffered_events);
     }
 
+    #[cfg(feature = "custom_cursor")]
     fn update_cursors(&mut self, event_loop: &ActiveEventLoop) {
         let mut windows_state: SystemState<(
             NonSendMut<WinitWindows>,

docs/cargo_features.md

@@ -34,6 +34,7 @@ The default feature set enables most of the expected features of a game engine,
 |bevy_ui|A custom ECS-driven UI framework|
 |bevy_ui_picking_backend|Provides an implementation for picking ui|
 |bevy_winit|winit window and input backend|
+|custom_cursor|Enable winit custom cursor support|
 |default_font|Include a default font, containing only ASCII characters, at the cost of a 20kB binary size increase|
 |hdr|HDR image format support|
 |ktx2|KTX2 compressed texture support|

examples/window/screenshot.rs

@@ -2,11 +2,9 @@
 
 use bevy::{
     prelude::*,
-    render::view::{
-        cursor::CursorIcon,
-        screenshot::{save_to_disk, Capturing, Screenshot},
-    },
+    render::view::screenshot::{save_to_disk, Capturing, Screenshot},
     window::SystemCursorIcon,
+    winit::cursor::CursorIcon,
 };
 
 fn main() {

examples/window/window_settings.rs

@@ -5,8 +5,8 @@ use bevy::{
     core::FrameCount,
     diagnostic::{FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin},
     prelude::*,
-    render::view::cursor::{CursorIcon, CustomCursor},
     window::{CursorGrabMode, PresentMode, SystemCursorIcon, WindowLevel, WindowTheme},
+    winit::cursor::{CursorIcon, CustomCursor},
 };
 
 fn main() {