Move CustomCursor to bevy_winit/src/custom_cursor.rs (#17381)

# Objective

- Follow up work from
https://github.com/bevyengine/bevy/pull/17121#issuecomment-2576615700 to
keep the `cursor.rs` file more manageable.

## Solution

- Move `CustomCursor` and make it compile.

## Testing

- Ran the example: `cargo run --example custom_cursor_image
--features=custom_cursor`
- CI

crates/bevy_winit/src/cursor.rs

@@ -15,7 +15,7 @@ use crate::{
 };
 use bevy_app::{App, Last, Plugin};
 #[cfg(feature = "custom_cursor")]
-use bevy_asset::{Assets, Handle};
+use bevy_asset::Assets;
 #[cfg(feature = "custom_cursor")]
 use bevy_ecs::system::Res;
 use bevy_ecs::{
@@ -29,15 +29,16 @@ use bevy_ecs::{
     world::{OnRemove, Ref},
 };
 #[cfg(feature = "custom_cursor")]
-use bevy_image::{Image, TextureAtlas, TextureAtlasLayout};
-#[cfg(feature = "custom_cursor")]
-use bevy_math::URect;
+use bevy_image::{Image, TextureAtlasLayout};
 use bevy_reflect::{std_traits::ReflectDefault, Reflect};
 use bevy_utils::HashSet;
 use bevy_window::{SystemCursorIcon, Window};
 #[cfg(feature = "custom_cursor")]
 use tracing::warn;
 
+#[cfg(feature = "custom_cursor")]
+pub use crate::custom_cursor::CustomCursor;
+
 pub(crate) struct CursorPlugin;
 
 impl Plugin for CursorPlugin {
@@ -75,51 +76,6 @@ impl From<SystemCursorIcon> for CursorIcon {
     }
 }
 
-#[cfg(feature = "custom_cursor")]
-impl From<CustomCursor> for CursorIcon {
-    fn from(cursor: CustomCursor) -> Self {
-        CursorIcon::Custom(cursor)
-    }
-}
-
-#[cfg(feature = "custom_cursor")]
-/// Custom cursor image data.
-#[derive(Debug, Clone, Reflect, PartialEq, Eq, Hash)]
-pub enum CustomCursor {
-    /// Image to use as a cursor.
-    Image {
-        /// The image must be in 8 bit int or 32 bit float rgba. PNG images
-        /// work well for this.
-        handle: Handle<Image>,
-        /// The (optional) texture atlas used to render the image.
-        texture_atlas: Option<TextureAtlas>,
-        /// Whether the image should be flipped along its x-axis.
-        flip_x: bool,
-        /// Whether the image should be flipped along its y-axis.
-        flip_y: bool,
-        /// An optional rectangle representing the region of the image to
-        /// render, instead of rendering the full image. This is an easy one-off
-        /// alternative to using a [`TextureAtlas`].
-        ///
-        /// When used with a [`TextureAtlas`], the rect is offset by the atlas's
-        /// minimal (top-left) corner position.
-        rect: Option<URect>,
-        /// X and Y coordinates of the hotspot in pixels. The hotspot must be
-        /// within the image bounds.
-        hotspot: (u16, u16),
-    },
-    #[cfg(all(target_family = "wasm", target_os = "unknown"))]
-    /// A URL to an image to use as the cursor.
-    Url {
-        /// Web URL to an image to use as the cursor. PNGs preferred. Cursor
-        /// creation can fail if the image is invalid or not reachable.
-        url: String,
-        /// X and Y coordinates of the hotspot in pixels. The hotspot must be
-        /// within the image bounds.
-        hotspot: (u16, u16),
-    },
-}
-
 fn update_cursors(
     mut commands: Commands,
     windows: Query<(Entity, Ref<CursorIcon>), With<Window>>,

crates/bevy_winit/src/custom_cursor.rs

@@ -1,10 +1,54 @@
 use bevy_app::{App, Plugin};
-use bevy_asset::Assets;
+use bevy_asset::{Assets, Handle};
 use bevy_image::{Image, TextureAtlas, TextureAtlasLayout, TextureAtlasPlugin};
 use bevy_math::{ops, Rect, URect, UVec2, Vec2};
+use bevy_reflect::Reflect;
 use wgpu_types::TextureFormat;
 
-use crate::state::CustomCursorCache;
+use crate::{cursor::CursorIcon, state::CustomCursorCache};
+
+/// Custom cursor image data.
+#[derive(Debug, Clone, Reflect, PartialEq, Eq, Hash)]
+pub enum CustomCursor {
+    /// Image to use as a cursor.
+    Image {
+        /// The image must be in 8 bit int or 32 bit float rgba. PNG images
+        /// work well for this.
+        handle: Handle<Image>,
+        /// The (optional) texture atlas used to render the image.
+        texture_atlas: Option<TextureAtlas>,
+        /// Whether the image should be flipped along its x-axis.
+        flip_x: bool,
+        /// Whether the image should be flipped along its y-axis.
+        flip_y: bool,
+        /// An optional rectangle representing the region of the image to
+        /// render, instead of rendering the full image. This is an easy one-off
+        /// alternative to using a [`TextureAtlas`].
+        ///
+        /// When used with a [`TextureAtlas`], the rect is offset by the atlas's
+        /// minimal (top-left) corner position.
+        rect: Option<URect>,
+        /// X and Y coordinates of the hotspot in pixels. The hotspot must be
+        /// within the image bounds.
+        hotspot: (u16, u16),
+    },
+    #[cfg(all(target_family = "wasm", target_os = "unknown"))]
+    /// A URL to an image to use as the cursor.
+    Url {
+        /// Web URL to an image to use as the cursor. PNGs preferred. Cursor
+        /// creation can fail if the image is invalid or not reachable.
+        url: String,
+        /// X and Y coordinates of the hotspot in pixels. The hotspot must be
+        /// within the image bounds.
+        hotspot: (u16, u16),
+    },
+}
+
+impl From<CustomCursor> for CursorIcon {
+    fn from(cursor: CustomCursor) -> Self {
+        CursorIcon::Custom(cursor)
+    }
+}
 
 /// Adds support for custom cursors.
 pub(crate) struct CustomCursorPlugin;