add side-aware keys comparison on mod update

Author: eugenesvk

src/platform_impl/windows/event_loop.rs

@@ -937,10 +937,17 @@ fn update_modifiers(window: HWND, userdata: &WindowData) {
         layouts.get_mods()
     };
 
+    let mut send_event = false;
     let mut window_state = userdata.window_state.lock().unwrap();
+    if window_state.modifiers_keys != modifiers.pressed_mods() {
+        window_state.modifiers_keys = modifiers.pressed_mods();
+        send_event = true;
+    }
     if window_state.modifiers_state != modifiers.state() {
         window_state.modifiers_state = modifiers.state();
-
+        send_event = true;
+    }
+    if send_event {
         // Drop lock
         drop(window_state);
 

src/platform_impl/windows/window_state.rs

@@ -17,7 +17,7 @@ use windows_sys::Win32::UI::WindowsAndMessaging::{
     WS_MINIMIZEBOX, WS_OVERLAPPEDWINDOW, WS_POPUP, WS_SIZEBOX, WS_SYSMENU, WS_VISIBLE,
 };
 use winit_core::icon::Icon;
-use winit_core::keyboard::ModifiersState;
+use winit_core::keyboard::{ModifiersKeys, ModifiersState};
 use winit_core::monitor::Fullscreen;
 use winit_core::window::{Theme, WindowAttributes};
 
@@ -41,6 +41,7 @@ pub(crate) struct WindowState {
     pub scale_factor: f64,
 
     pub modifiers_state: ModifiersState,
+    pub modifiers_keys: ModifiersKeys,
     pub fullscreen: Option<Fullscreen>,
     pub current_theme: Theme,
     pub preferred_theme: Option<Theme>,
@@ -172,6 +173,7 @@ impl WindowState {
             scale_factor,
 
             modifiers_state: ModifiersState::default(),
+            modifiers_keys: ModifiersKeys::default(),
             fullscreen: None,
             current_theme,
             preferred_theme,

winit-core/src/event.rs

@@ -825,6 +825,11 @@ impl Modifiers {
         self.state
     }
 
+    /// The logical state of the modifier keys.
+    pub fn pressed_mods(&self) -> ModifiersKeys {
+        self.pressed_mods
+    }
+
     /// The logical state of the left shift key.
     pub fn lshift_state(&self) -> ModifiersKeyState {
         self.mod_state(ModifiersKeys::LSHIFT)