Added basic mouse capture API (#679)

Added basic cursor lock API

Author: alexb910

Cargo.toml

@@ -293,3 +293,4 @@ required-features = ["bevy_winit"]
 name = "assets_wasm"
 path = "examples/wasm/assets_wasm.rs"
 required-features = ["bevy_winit"]
+

crates/bevy_window/src/window.rs

@@ -40,6 +40,8 @@ pub struct Window {
     vsync: bool,
     resizable: bool,
     decorations: bool,
+    cursor_visible: bool,
+    cursor_locked: bool,
     mode: WindowMode,
     #[cfg(target_arch = "wasm32")]
     pub canvas: Option<String>,
@@ -68,6 +70,12 @@ pub enum WindowCommand {
     SetDecorations {
         decorations: bool,
     },
+    SetCursorLockMode {
+        locked: bool,
+    },
+    SetCursorVisibility {
+        visible: bool,
+    },
 }
 
 /// Defines the way a window is displayed
@@ -92,6 +100,8 @@ impl Window {
             vsync: window_descriptor.vsync,
             resizable: window_descriptor.resizable,
             decorations: window_descriptor.decorations,
+            cursor_visible: window_descriptor.cursor_visible,
+            cursor_locked: window_descriptor.cursor_locked,
             mode: window_descriptor.mode,
             #[cfg(target_arch = "wasm32")]
             canvas: window_descriptor.canvas.clone(),
@@ -165,6 +175,27 @@ impl Window {
             .push(WindowCommand::SetDecorations { decorations });
     }
 
+    pub fn cursor_locked(&self) -> bool {
+        self.cursor_locked
+    }
+
+    pub fn set_cursor_lock_mode(&mut self, lock_mode: bool) {
+        self.cursor_locked = lock_mode;
+        self.command_queue
+            .push(WindowCommand::SetCursorLockMode { locked: lock_mode });
+    }
+
+    pub fn cursor_visible(&self) -> bool {
+        self.cursor_visible
+    }
+
+    pub fn set_cursor_visibility(&mut self, visibile_mode: bool) {
+        self.cursor_visible = visibile_mode;
+        self.command_queue.push(WindowCommand::SetCursorVisibility {
+            visible: visibile_mode,
+        });
+    }
+
     pub fn mode(&self) -> WindowMode {
         self.mode
     }
@@ -191,6 +222,8 @@ pub struct WindowDescriptor {
     pub vsync: bool,
     pub resizable: bool,
     pub decorations: bool,
+    pub cursor_visible: bool,
+    pub cursor_locked: bool,
     pub mode: WindowMode,
     #[cfg(target_arch = "wasm32")]
     pub canvas: Option<String>,
@@ -210,6 +243,8 @@ impl Default for WindowDescriptor {
             vsync: true,
             resizable: true,
             decorations: true,
+            cursor_locked: false,
+            cursor_visible: true,
             mode: WindowMode::Windowed,
             #[cfg(target_arch = "wasm32")]
             canvas: None,

crates/bevy_winit/src/lib.rs

@@ -84,6 +84,14 @@ fn change_window(_: &mut World, resources: &mut Resources) {
                     let window = winit_windows.get_window(id).unwrap();
                     window.set_decorations(decorations);
                 }
+                bevy_window::WindowCommand::SetCursorLockMode { locked } => {
+                    let window = winit_windows.get_window(id).unwrap();
+                    window.set_cursor_grab(locked).unwrap();
+                }
+                bevy_window::WindowCommand::SetCursorVisibility { visible } => {
+                    let window = winit_windows.get_window(id).unwrap();
+                    window.set_cursor_visible(visible);
+                }
             }
         }
     }

crates/bevy_winit/src/winit_windows.rs

@@ -71,6 +71,11 @@ impl WinitWindows {
 
         let winit_window = winit_window_builder.build(&event_loop).unwrap();
 
+        winit_window
+            .set_cursor_grab(window.cursor_locked())
+            .unwrap();
+        winit_window.set_cursor_visible(window.cursor_visible());
+
         self.window_id_to_winit
             .insert(window.id(), winit_window.id());
         self.winit_to_window_id

examples/window/window_settings.rs

@@ -13,6 +13,7 @@ fn main() {
         })
         .add_default_plugins()
         .add_system(change_title.system())
+        .add_system(toggle_cursor.system())
         .run();
 }
 
@@ -24,3 +25,12 @@ fn change_title(time: Res<Time>, mut windows: ResMut<Windows>) {
         time.seconds_since_startup.round()
     ));
 }
+
+/// This system toggles the cursor's visibility when the space bar is pressed
+fn toggle_cursor(input: Res<Input<KeyCode>>, mut windows: ResMut<Windows>) {
+    let window = windows.get_primary_mut().unwrap();
+    if input.just_pressed(KeyCode::Space) {
+        window.set_cursor_lock_mode(!window.cursor_locked());
+        window.set_cursor_visibility(!window.cursor_visible());
+    }
+}