Add window entity to mouse and keyboard events (#8852)

# Objective

- Resolves #4649 

## Solution

- Added the window entity to `KeyboardInput`, `MouseButtonInput`, and
`MouseWheel` events.

crates/bevy_input/src/keyboard.rs

@@ -1,4 +1,5 @@
 use crate::{ButtonState, Input};
+use bevy_ecs::entity::Entity;
 use bevy_ecs::{
     change_detection::DetectChangesMut,
     event::{Event, EventReader},
@@ -32,6 +33,8 @@ pub struct KeyboardInput {
     pub key_code: Option<KeyCode>,
     /// The press state of the key.
     pub state: ButtonState,
+    /// Window that received the input.
+    pub window: Entity,
 }
 
 /// Updates the [`Input<KeyCode>`] resource with the latest [`KeyboardInput`] events.

crates/bevy_input/src/mouse.rs

@@ -1,4 +1,5 @@
 use crate::{ButtonState, Input};
+use bevy_ecs::entity::Entity;
 use bevy_ecs::{
     change_detection::DetectChangesMut,
     event::{Event, EventReader},
@@ -30,6 +31,8 @@ pub struct MouseButtonInput {
     pub button: MouseButton,
     /// The pressed state of the button.
     pub state: ButtonState,
+    /// Window that received the input.
+    pub window: Entity,
 }
 
 /// A button on a mouse device.
@@ -124,6 +127,8 @@ pub struct MouseWheel {
     pub x: f32,
     /// The vertical scroll value.
     pub y: f32,
+    /// Window that received the input.
+    pub window: Entity,
 }
 
 /// Updates the [`Input<MouseButton>`] resource with the latest [`MouseButtonInput`] events.

crates/bevy_winit/src/converters.rs

@@ -1,3 +1,4 @@
+use bevy_ecs::entity::Entity;
 use bevy_input::{
     keyboard::{KeyCode, KeyboardInput},
     mouse::MouseButton,
@@ -7,11 +8,15 @@ use bevy_input::{
 use bevy_math::Vec2;
 use bevy_window::{CursorIcon, WindowLevel, WindowTheme};
 
-pub fn convert_keyboard_input(keyboard_input: &winit::event::KeyboardInput) -> KeyboardInput {
+pub fn convert_keyboard_input(
+    keyboard_input: &winit::event::KeyboardInput,
+    window: Entity,
+) -> KeyboardInput {
     KeyboardInput {
         scan_code: keyboard_input.scancode,
         state: convert_element_state(keyboard_input.state),
         key_code: keyboard_input.virtual_keycode.map(convert_virtual_key_code),
+        window,
     }
 }
 

crates/bevy_winit/src/lib.rs

@@ -453,7 +453,7 @@ pub fn winit_runner(mut app: App) {
                     WindowEvent::KeyboardInput { ref input, .. } => {
                         input_events
                             .keyboard_input
-                            .send(converters::convert_keyboard_input(input));
+                            .send(converters::convert_keyboard_input(input, window_entity));
                     }
                     WindowEvent::CursorMoved { position, .. } => {
                         let physical_position = DVec2::new(position.x, position.y);
@@ -482,6 +482,7 @@ pub fn winit_runner(mut app: App) {
                         input_events.mouse_button_input.send(MouseButtonInput {
                             button: converters::convert_mouse_button(button),
                             state: converters::convert_element_state(state),
+                            window: window_entity,
                         });
                     }
                     WindowEvent::TouchpadMagnify { delta, .. } => {
@@ -500,6 +501,7 @@ pub fn winit_runner(mut app: App) {
                                 unit: MouseScrollUnit::Line,
                                 x,
                                 y,
+                                window: window_entity,
                             });
                         }
                         event::MouseScrollDelta::PixelDelta(p) => {
@@ -507,6 +509,7 @@ pub fn winit_runner(mut app: App) {
                                 unit: MouseScrollUnit::Pixel,
                                 x: p.x as f32,
                                 y: p.y as f32,
+                                window: window_entity,
                             });
                         }
                     },