Expose public Window::set_mouse_cursor method (#161)

The X11 backend has a full implementation of a `Window::set_mouse_cursor` method, but it isn't exposed via any public interface, which results in a lot of warnings for unused code. Add a public `set_mouse_cursor` method, along with stubbed-out versions in the Windows and macOS backends.

src/macos/window.rs

@@ -24,8 +24,8 @@ use raw_window_handle::{
 };
 
 use crate::{
-    Event, EventStatus, Size, WindowEvent, WindowHandler, WindowInfo, WindowOpenOptions,
-    WindowScalePolicy,
+    Event, EventStatus, MouseCursor, Size, WindowEvent, WindowHandler, WindowInfo,
+    WindowOpenOptions, WindowScalePolicy,
 };
 
 use super::keyboard::KeyboardState;
@@ -302,6 +302,10 @@ impl Window {
         }
     }
 
+    pub fn set_mouse_cursor(&mut self, _mouse_cursor: MouseCursor) {
+        todo!()
+    }
+
     #[cfg(feature = "opengl")]
     pub fn gl_context(&self) -> Option<&GlContext> {
         self.gl_context.as_ref()

src/win/window.rs

@@ -34,7 +34,7 @@ use raw_window_handle::{
 const BV_WINDOW_MUST_CLOSE: UINT = WM_USER + 1;
 
 use crate::{
-    Event, MouseButton, MouseEvent, PhyPoint, PhySize, ScrollDelta, Size, WindowEvent,
+    Event, MouseButton, MouseCursor, MouseEvent, PhyPoint, PhySize, ScrollDelta, Size, WindowEvent,
     WindowHandler, WindowInfo, WindowOpenOptions, WindowScalePolicy,
 };
 
@@ -765,6 +765,10 @@ impl Window<'_> {
         self.state.deferred_tasks.borrow_mut().push_back(task);
     }
 
+    pub fn set_mouse_cursor(&mut self, _mouse_cursor: MouseCursor) {
+        todo!()
+    }
+
     #[cfg(feature = "opengl")]
     pub fn gl_context(&self) -> Option<&GlContext> {
         self.state.gl_context.as_ref()

src/window.rs

@@ -6,7 +6,7 @@ use raw_window_handle::{
 
 use crate::event::{Event, EventStatus};
 use crate::window_open_options::WindowOpenOptions;
-use crate::Size;
+use crate::{MouseCursor, Size};
 
 #[cfg(target_os = "macos")]
 use crate::macos as platform;
@@ -101,6 +101,10 @@ impl<'a> Window<'a> {
         self.window.resize(size);
     }
 
+    pub fn set_mouse_cursor(&mut self, cursor: MouseCursor) {
+        self.window.set_mouse_cursor(cursor);
+    }
+
     /// If provided, then an OpenGL context will be created for this window. You'll be able to
     /// access this context through [crate::Window::gl_context].
     #[cfg(feature = "opengl")]

src/x11/window.rs

@@ -97,7 +97,6 @@ pub struct Window {
     window_id: u32,
     window_info: WindowInfo,
     visual_id: u32,
-    // FIXME: There's all this mouse cursor logic but it's never actually used, is this correct?
     mouse_cursor: MouseCursor,
 
     frame_interval: Duration,

src/x11/xcb_connection.rs

@@ -19,7 +19,6 @@ pub struct XcbConnection {
 
     pub(crate) atoms: Atoms,
 
-    // FIXME: Same here, there's a ton of unused cursor machinery in here
     pub(super) cursor_cache: HashMap<MouseCursor, u32>,
 }