move custom mouse cursor functionality to separate struct

this is to not have the main Mouse struct be tied to our indexed-colour
Bitmap graphics implementation (i'm not currently ready to try to
generify this either ...)

ggdt/src/system/input_devices/mouse/cursor.rs

@@ -0,0 +1,197 @@
+use crate::graphics::*;
+use crate::math::*;
+
+use super::*;
+
+const DEFAULT_MOUSE_CURSOR_HOTSPOT_X: u32 = 0;
+const DEFAULT_MOUSE_CURSOR_HOTSPOT_Y: u32 = 0;
+const DEFAULT_MOUSE_CURSOR_WIDTH: usize = 16;
+const DEFAULT_MOUSE_CURSOR_HEIGHT: usize = 16;
+
+#[rustfmt::skip]
+const DEFAULT_MOUSE_CURSOR: [u8; DEFAULT_MOUSE_CURSOR_WIDTH * DEFAULT_MOUSE_CURSOR_HEIGHT] = [
+	0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x0f, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x0f, 0x00, 0x00, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0x00, 0x00, 0xff, 0xff, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
+];
+
+#[derive(Debug)]
+pub struct CustomMouseCursor {
+	last_x: i32,
+	last_y: i32,
+	cursor: Bitmap,
+	cursor_background: Bitmap,
+	cursor_hotspot_x: u32,
+	cursor_hotspot_y: u32,
+	cursor_enabled: bool,
+}
+
+impl CustomMouseCursor {
+	pub fn new() -> Self {
+		let (cursor, cursor_background, cursor_hotspot_x, cursor_hotspot_y) = Self::get_default_mouse_cursor();
+
+		CustomMouseCursor {
+			last_x: 0,
+			last_y: 0,
+			cursor,
+			cursor_background,
+			cursor_hotspot_x,
+			cursor_hotspot_y,
+			cursor_enabled: false,
+		}
+	}
+
+	/// Returns a reference to the current mouse cursor bitmap.
+	#[inline]
+	pub fn cursor_bitmap(&self) -> &Bitmap {
+		&self.cursor
+	}
+
+	/// Returns the current mouse cursor's "hotspot" x coordinate.
+	#[inline]
+	pub fn cursor_hotspot_x(&self) -> u32 {
+		self.cursor_hotspot_x
+	}
+
+	/// Returns the current mouse cursor's "hotspot" y coordinate.
+	#[inline]
+	pub fn cursor_hotspot_y(&self) -> u32 {
+		self.cursor_hotspot_y
+	}
+
+	/// Returns true if mouse cursor bitmap rendering is enabled.
+	#[inline]
+	pub fn is_cursor_enabled(&self) -> bool {
+		self.cursor_enabled
+	}
+
+	/// Enables or disables mouse cursor bitmap rendering.
+	#[inline]
+	pub fn enable_cursor(&mut self, enable: bool) {
+		self.cursor_enabled = enable;
+	}
+
+	/// Sets the [`Bitmap`] used to display the mouse cursor and the "hotspot" coordinate. The
+	/// bitmap provided here should be set up to use color 255 as the transparent color.
+	///
+	/// # Arguments
+	///
+	/// * `cursor`: the bitmap to be used to display the mouse cursor on screen
+	/// * `hotspot_x`: the "hotspot" x coordinate
+	/// * `hotspot_y`: the "hotspot" y coordinate.
+	pub fn set_mouse_cursor(&mut self, cursor: Bitmap, hotspot_x: u32, hotspot_y: u32) {
+		self.cursor = cursor;
+		self.cursor_background = Bitmap::new(self.cursor.width(), self.cursor.height()).unwrap();
+		self.cursor_hotspot_x = hotspot_x;
+		self.cursor_hotspot_y = hotspot_y;
+	}
+
+	/// Resets the mouse cursor bitmap and "hotspot" coordinate back to the default settings.
+	pub fn set_default_mouse_cursor(&mut self) {
+		let (cursor, background, hotspot_x, hotspot_y) = Self::get_default_mouse_cursor();
+		self.cursor = cursor;
+		self.cursor_background = background;
+		self.cursor_hotspot_x = hotspot_x;
+		self.cursor_hotspot_y = hotspot_y;
+	}
+
+	#[inline]
+	fn get_cursor_render_position(&self) -> (i32, i32) {
+		(
+			self.last_x - self.cursor_hotspot_x as i32,
+			self.last_y - self.cursor_hotspot_y as i32,
+		)
+	}
+
+	/// Renders the mouse cursor bitmap onto the destination bitmap at the mouse's current
+	/// position. The destination bitmap specified is usually the [`SystemResources`]'s video
+	/// backbuffer bitmap. The background on the destination bitmap is saved internally and a
+	/// subsequent call to [`Self::hide`] will restore the background.
+	///
+	/// If mouse cursor rendering is not currently enabled, this method does nothing.
+	///
+	/// Applications will not normally need to call this method, as if mouse cursor rendering is
+	/// enabled, this will be automatically handled by [`SystemResources::display`].
+	///
+	/// [`SystemResources`]: crate::system::SystemResources
+	/// [`SystemResources::display`]: crate::system::SystemResources::display
+	pub fn render(&mut self, dest: &mut Bitmap) {
+		if !self.cursor_enabled {
+			return;
+		}
+
+		let (x, y) = self.get_cursor_render_position();
+
+		// preserve existing background first
+		self.cursor_background.blit_region(
+			BlitMethod::Solid,
+			&dest,
+			&Rect::new(x, y, self.cursor.width(), self.cursor.height()),
+			0,
+			0,
+		);
+
+		dest.blit(BlitMethod::Transparent(255), &self.cursor, x, y);
+	}
+
+	/// Restores the original destination bitmap contents where the mouse cursor bitmap was
+	/// rendered to during the previous call to [`Self::render`]. The destination bitmap
+	/// specified is usually the [`SystemResources`]'s video backbuffer bitmap.
+	///
+	/// If mouse cursor rendering is not currently enabled, this method does nothing.
+	///
+	/// Applications will not normally need to call this method, as if mouse cursor rendering is
+	/// enabled, this will be automatically handled by [`SystemResources::display`].
+	///
+	/// [`SystemResources`]: crate::system::SystemResources
+	/// [`SystemResources::display`]: crate::system::SystemResources::display
+	pub fn hide(&mut self, dest: &mut Bitmap) {
+		if !self.cursor_enabled {
+			return;
+		}
+
+		let (x, y) = self.get_cursor_render_position();
+		dest.blit(BlitMethod::Solid, &self.cursor_background, x, y);
+	}
+
+	/// Updates current state from the given [`Mouse`] device's state, ensuring that subsequent calls to render
+	/// a custom mouse cursor reflect the current mouse state. Application's should not normally need to call
+	/// this directly as it will be called by [`SystemResources::update`].
+	///
+	/// [`SystemResources::update`]: crate::system::SystemResources::update
+	pub fn update(&mut self, mouse: &Mouse) {
+		self.last_x = mouse.x;
+		self.last_y = mouse.y;
+	}
+
+	fn get_default_mouse_cursor() -> (Bitmap, Bitmap, u32, u32) {
+		let mut cursor = Bitmap::new(
+			DEFAULT_MOUSE_CURSOR_WIDTH as u32,
+			DEFAULT_MOUSE_CURSOR_HEIGHT as u32,
+		)
+			.unwrap();
+		cursor.pixels_mut().copy_from_slice(&DEFAULT_MOUSE_CURSOR);
+
+		let cursor_background = Bitmap::new(cursor.width(), cursor.height()).unwrap();
+
+		(
+			cursor,
+			cursor_background,
+			DEFAULT_MOUSE_CURSOR_HOTSPOT_X,
+			DEFAULT_MOUSE_CURSOR_HOTSPOT_Y,
+		)
+	}
+}

ggdt/src/system/input_devices/mouse/mod.rs

@@ -5,36 +5,13 @@ use crate::system::MouseEvent;
 use super::*;
 
 pub use self::buttons::*;
+pub use self::cursor::*;
 
 pub mod buttons;
+pub mod cursor;
 
 const MAX_BUTTONS: usize = 32;
 
-const DEFAULT_MOUSE_CURSOR_HOTSPOT_X: u32 = 0;
-const DEFAULT_MOUSE_CURSOR_HOTSPOT_Y: u32 = 0;
-const DEFAULT_MOUSE_CURSOR_WIDTH: usize = 16;
-const DEFAULT_MOUSE_CURSOR_HEIGHT: usize = 16;
-
-#[rustfmt::skip]
-const DEFAULT_MOUSE_CURSOR: [u8; DEFAULT_MOUSE_CURSOR_WIDTH * DEFAULT_MOUSE_CURSOR_HEIGHT] = [
-	0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x0f, 0x0f, 0x0f, 0x0f, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x0f, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x0f, 0x00, 0x00, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0x00, 0x00, 0xff, 0xff, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x0f, 0x0f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
-];
-
 /// Holds the current state of the mouse.
 ///
 /// Must be explicitly updated each frame by calling `handle_event` each frame for all SDL2 events
@@ -49,29 +26,16 @@ pub struct Mouse {
 	x_delta: i32,
 	y_delta: i32,
 	buttons: [ButtonState; MAX_BUTTONS],
-	cursor: Bitmap,
-	cursor_background: Bitmap,
-	cursor_hotspot_x: u32,
-	cursor_hotspot_y: u32,
-	cursor_enabled: bool,
 }
 
 impl Mouse {
 	pub fn new() -> Mouse {
-		let (cursor, cursor_background, cursor_hotspot_x, cursor_hotspot_y) =
-			Self::get_default_mouse_cursor();
-
 		Mouse {
 			x: 0,
 			y: 0,
 			x_delta: 0,
 			y_delta: 0,
 			buttons: [ButtonState::Idle; MAX_BUTTONS],
-			cursor,
-			cursor_background,
-			cursor_hotspot_x,
-			cursor_hotspot_y,
-			cursor_enabled: false,
 		}
 	}
 
@@ -131,137 +95,6 @@ impl Mouse {
 		self.buttons[button] == ButtonState::Released
 	}
 
-	/// Returns a reference to the current mouse cursor bitmap.
-	#[inline]
-	pub fn cursor_bitmap(&self) -> &Bitmap {
-		&self.cursor
-	}
-
-	/// Returns the current mouse cursor's "hotspot" x coordinate.
-	#[inline]
-	pub fn cursor_hotspot_x(&self) -> u32 {
-		self.cursor_hotspot_x
-	}
-
-	/// Returns the current mouse cursor's "hotspot" y coordinate.
-	#[inline]
-	pub fn cursor_hotspot_y(&self) -> u32 {
-		self.cursor_hotspot_y
-	}
-
-	/// Returns true if mouse cursor bitmap rendering is enabled.
-	#[inline]
-	pub fn is_cursor_enabled(&self) -> bool {
-		self.cursor_enabled
-	}
-
-	/// Enables or disables mouse cursor bitmap rendering.
-	#[inline]
-	pub fn enable_cursor(&mut self, enable: bool) {
-		self.cursor_enabled = enable;
-	}
-
-	/// Sets the [`Bitmap`] used to display the mouse cursor and the "hotspot" coordinate. The
-	/// bitmap provided here should be set up to use color 255 as the transparent color.
-	///
-	/// # Arguments
-	///
-	/// * `cursor`: the bitmap to be used to display the mouse cursor on screen
-	/// * `hotspot_x`: the "hotspot" x coordinate
-	/// * `hotspot_y`: the "hotspot" y coordinate.
-	pub fn set_mouse_cursor(&mut self, cursor: Bitmap, hotspot_x: u32, hotspot_y: u32) {
-		self.cursor = cursor;
-		self.cursor_background = Bitmap::new(self.cursor.width(), self.cursor.height()).unwrap();
-		self.cursor_hotspot_x = hotspot_x;
-		self.cursor_hotspot_y = hotspot_y;
-	}
-
-	/// Resets the mouse cursor bitmap and "hotspot" coordinate back to the default settings.
-	pub fn set_default_mouse_cursor(&mut self) {
-		let (cursor, background, hotspot_x, hotspot_y) = Self::get_default_mouse_cursor();
-		self.cursor = cursor;
-		self.cursor_background = background;
-		self.cursor_hotspot_x = hotspot_x;
-		self.cursor_hotspot_y = hotspot_y;
-	}
-
-	fn get_default_mouse_cursor() -> (Bitmap, Bitmap, u32, u32) {
-		let mut cursor = Bitmap::new(
-			DEFAULT_MOUSE_CURSOR_WIDTH as u32,
-			DEFAULT_MOUSE_CURSOR_HEIGHT as u32,
-		)
-			.unwrap();
-		cursor.pixels_mut().copy_from_slice(&DEFAULT_MOUSE_CURSOR);
-
-		let cursor_background = Bitmap::new(cursor.width(), cursor.height()).unwrap();
-
-		(
-			cursor,
-			cursor_background,
-			DEFAULT_MOUSE_CURSOR_HOTSPOT_X,
-			DEFAULT_MOUSE_CURSOR_HOTSPOT_Y,
-		)
-	}
-
-	#[inline]
-	fn get_cursor_render_position(&self) -> (i32, i32) {
-		(
-			self.x - self.cursor_hotspot_x as i32,
-			self.y - self.cursor_hotspot_y as i32,
-		)
-	}
-
-	/// Renders the mouse cursor bitmap onto the destination bitmap at the mouse's current
-	/// position. The destination bitmap specified is assumed to be the [`System`]'s video
-	/// backbuffer bitmap. The background on the destination bitmap is saved internally and a
-	/// subsequent call to [`Mouse::hide_cursor`] will restore the background.
-	///
-	/// If mouse cursor rendering is not currently enabled, this method does nothing.
-	///
-	/// Applications will not normally need to call this method, as if mouse cursor rendering is
-	/// enabled, this will be automatically handled by [`System::display`].
-	///
-	/// [`System`]: crate::System
-	/// [`System::display`]: crate::System::display
-	pub fn render_cursor(&mut self, dest: &mut Bitmap) {
-		if !self.cursor_enabled {
-			return;
-		}
-
-		let (x, y) = self.get_cursor_render_position();
-
-		// preserve existing background first
-		self.cursor_background.blit_region(
-			BlitMethod::Solid,
-			&dest,
-			&Rect::new(x, y, self.cursor.width(), self.cursor.height()),
-			0,
-			0,
-		);
-
-		dest.blit(BlitMethod::Transparent(255), &self.cursor, x, y);
-	}
-
-	/// Restores the original destination bitmap contents where the mouse cursor bitmap was
-	/// rendered to during the previous call to [`Mouse::render_cursor`]. The destination bitmap
-	/// specified is assumed to be the [`System`]'s video backbuffer bitmap.
-	///
-	/// If mouse cursor rendering is not currently enabled, this method does nothing.
-	///
-	/// Applications will not normally need to call this method, as if mouse cursor rendering is
-	/// enabled, this will be automatically handled by [`System::display`].
-	///
-	/// [`System`]: crate::System
-	/// [`System::display`]: crate::System::display
-	pub fn hide_cursor(&mut self, dest: &mut Bitmap) {
-		if !self.cursor_enabled {
-			return;
-		}
-
-		let (x, y) = self.get_cursor_render_position();
-		dest.blit(BlitMethod::Solid, &self.cursor_background, x, y);
-	}
-
 	fn update_button_state(&mut self, button: u32, is_pressed: bool) {
 		let button_state = &mut self.buttons[button as usize];
 		*button_state = if is_pressed {

ggdt/src/system/res/dos_like.rs

@@ -165,6 +165,7 @@ impl SystemResourcesConfig for DosLikeConfig {
 
 		let keyboard = Keyboard::new();
 		let mouse = Mouse::new();
+		let cursor = CustomMouseCursor::new();
 
 		Ok(DosLike {
 			sdl_canvas,
@@ -178,6 +179,7 @@ impl SystemResourcesConfig for DosLikeConfig {
 			font,
 			keyboard,
 			mouse,
+			cursor,
         })
 	}
 }
@@ -218,6 +220,10 @@ pub struct DosLike {
 	/// The current mouse state. To ensure it is updated each frame, you should call
 	/// [`System::do_events`] or [`System::do_events_with`] each frame.
 	pub mouse: Mouse,
+
+	/// Manages custom mouse cursor graphics and state. Use this to set/unset a custom mouse cursor bitmap.
+	/// When set, rendering should occur automatically during calls to [`SystemResources::display`].
+	pub cursor: CustomMouseCursor,
 }
 
 impl std::fmt::Debug for DosLike {
@@ -236,6 +242,8 @@ impl std::fmt::Debug for DosLike {
 
 impl SystemResources for DosLike {
 	fn update(&mut self) -> Result<(), SystemResourcesError> {
+		self.cursor.update(&self.mouse);
+
 		match self.audio_queue.apply(&mut self.audio) {
 			Ok(_) => Ok(()),
 			Err(error) => Err(SystemResourcesError::AudioDeviceError(error))
@@ -245,7 +253,7 @@ impl SystemResources for DosLike {
 	/// Takes the `video` backbuffer bitmap and `palette` and renders it to the window, up-scaled
 	/// to fill the window (preserving aspect ratio of course).
 	fn display(&mut self) -> Result<(), SystemResourcesError> {
-        self.mouse.render_cursor(&mut self.video);
+        self.cursor.render(&mut self.video);
 
         // convert application framebuffer to 32-bit RGBA pixels, and then upload it to the SDL
         // texture so it will be displayed on screen
@@ -262,7 +270,7 @@ impl SystemResources for DosLike {
         }
         self.sdl_canvas.present();
 
-        self.mouse.hide_cursor(&mut self.video);
+        self.cursor.hide(&mut self.video);
 
         Ok(())
 	}