Add window::monitor_size task

runtime/src/window.rs

@@ -175,6 +175,9 @@ pub enum Action {
     /// Set the window size increment.
     SetResizeIncrements(Id, Option<Size>),
 
+    /// Get the size of the monitor on which the window currently resides in logical dimensions.
+    GetMonitorSize(Id, oneshot::Sender<Option<Size>>),
+
     /// Redraws all the windows.
     RedrawAll,
 
@@ -491,3 +494,10 @@ pub fn enable_mouse_passthrough<Message>(id: Id) -> Task<Message> {
 pub fn disable_mouse_passthrough<Message>(id: Id) -> Task<Message> {
     task::effect(crate::Action::Window(Action::DisableMousePassthrough(id)))
 }
+
+/// Get the size of the monitor on which the window currently resides in logical dimensions.
+pub fn monitor_size(id: Id) -> Task<Option<Size>> {
+    task::oneshot(move |channel| {
+        crate::Action::Window(Action::GetMonitorSize(id, channel))
+    })
+}

winit/src/lib.rs

@@ -1631,7 +1631,7 @@ fn run_action<'a, P, C>(
                     let _ = channel.send(core::window::Screenshot::new(
                         bytes,
                         window.state.physical_size(),
-                        window.state.viewport().scale_factor(),
+                        window.state.scale_factor(),
                     ));
                 }
             }
@@ -1645,6 +1645,18 @@ fn run_action<'a, P, C>(
                     let _ = window.raw.set_cursor_hittest(true);
                 }
             }
+            window::Action::GetMonitorSize(id, channel) => {
+                if let Some(window) = window_manager.get(id) {
+                    let size = window.raw.current_monitor().map(|monitor| {
+                        let scale = window.state.scale_factor();
+                        let size = monitor.size().to_logical(f64::from(scale));
+
+                        Size::new(size.width, size.height)
+                    });
+
+                    let _ = channel.send(size);
+                }
+            }
             window::Action::RedrawAll => {
                 for (_id, window) in window_manager.iter_mut() {
                     window.raw.request_redraw();