Merge pull request #2242 from dtzxporter/workaround-windows-issue-pt2

Implement win32 workaround for multi_window application as well. Also trigger AboutToWait for Moved as well.

Author: hecrj

winit/src/application.rs

@@ -250,7 +250,8 @@ where
             if matches!(
                 event,
                 winit::event::Event::WindowEvent {
-                    event: winit::event::WindowEvent::Resized(_),
+                    event: winit::event::WindowEvent::Resized(_)
+                        | winit::event::WindowEvent::Moved(_),
                     ..
                 }
             ) {

winit/src/multi_window.rs

@@ -211,7 +211,7 @@ where
 
     let mut context = task::Context::from_waker(task::noop_waker_ref());
 
-    let _ = event_loop.run(move |event, event_loop| {
+    let process_event = move |event, event_loop: &winit::event_loop::EventLoopWindowTarget<_>| {
         if event_loop.exiting() {
             return;
         }
@@ -280,7 +280,35 @@ where
                 }
             };
         }
-    });
+    };
+
+    #[cfg(not(target_os = "windows"))]
+    let _ = event_loop.run(process_event);
+
+    // TODO: Remove when unnecessary
+    // On Windows, we emulate an `AboutToWait` event after every `Resized` event
+    // since the event loop does not resume during resize interaction.
+    // More details: https://github.com/rust-windowing/winit/issues/3272
+    #[cfg(target_os = "windows")]
+    {
+        let mut process_event = process_event;
+
+        let _ = event_loop.run(move |event, event_loop| {
+            if matches!(
+                event,
+                winit::event::Event::WindowEvent {
+                    event: winit::event::WindowEvent::Resized(_)
+                        | winit::event::WindowEvent::Moved(_),
+                    ..
+                }
+            ) {
+                process_event(event, event_loop);
+                process_event(winit::event::Event::AboutToWait, event_loop);
+            } else {
+                process_event(event, event_loop);
+            }
+        });
+    }
 
     Ok(())
 }