Win32 - Support rendering at max refresh rate of current displays (#21643)

* win32 - support rendering at max refresh rate for current displays

* win32 - set max framerate floor to 60

src/Avalonia.Base/Rendering/RenderLoop.cs

@@ -101,6 +101,8 @@ namespace Avalonia.Rendering
         /// <inheritdoc />
         public bool RunsInBackground => _timer.RunsInBackground;
 
+        internal IRenderTimer Timer => _timer;
+
         /// <inheritdoc />
         public void Wakeup()
         {

src/Windows/Avalonia.Win32/Win32Platform.cs

@@ -44,7 +44,7 @@ namespace Avalonia.Win32
         private static Win32PlatformOptions? s_options;
         private static Compositor? s_compositor;
         internal const int TIMERID_DISPATCHER = 1;
-
+        private const int DefaultFramesPerSecond = 60;
         private WndProc? _wndProcDelegate;
         private IntPtr _hwnd;
         private Win32DispatcherImpl _dispatcher;
@@ -87,7 +87,7 @@ namespace Avalonia.Win32
 
             Dispatcher.InitializeUIThreadDispatcher(s_instance._dispatcher);
             
-            var renderTimer = options.ShouldRenderOnUIThread ? new UiThreadRenderTimer(60) : new DefaultRenderTimer(60);
+            IRenderTimer renderTimer = options.ShouldRenderOnUIThread ? new UiThreadRenderTimer(DefaultFramesPerSecond) : new SleepLoopRenderTimer(DefaultFramesPerSecond);
             var clipboardImpl = new ClipboardImpl();
             var clipboard = new Clipboard(clipboardImpl);
 
@@ -133,7 +133,9 @@ namespace Avalonia.Win32
             
             if (OleContext.Current != null)
                 AvaloniaLocator.CurrentMutable.Bind<IPlatformDragSource>().ToSingleton<DragSource>();
-            
+
+            UpdateTimerFps();
+
             s_compositor = new Compositor( platformGraphics);
             AvaloniaLocator.CurrentMutable.Bind<Compositor>().ToConstant(s_compositor);
         }
@@ -196,6 +198,16 @@ namespace Avalonia.Win32
             return DefWindowProc(hWnd, msg, wParam, lParam);
         }
 
+        internal static void UpdateTimerFps()
+        {
+            var maxDisplayFrequency = Math.Max(60, Instance.Screen?.AllScreens?.Max(s => (s as WinScreen)?.Frequency) ?? 0);
+            if (AvaloniaLocator.Current.GetService<IRenderLoop>() is DefaultRenderLoop defaultRenderLoop &&
+                defaultRenderLoop.Timer is SleepLoopRenderTimer sleepLoopRenderTimer)
+            {
+                sleepLoopRenderTimer.DesiredFps = maxDisplayFrequency;
+            }
+        }
+
         private void CreateMessageWindow()
         {
             // Ensure that the delegate doesn't get garbage collected by storing it as a field.

src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs

@@ -1,11 +1,13 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using System.Linq;
 using System.Runtime.InteropServices;
 using Avalonia.Automation.Peers;
 using Avalonia.Controls;
 using Avalonia.Input;
 using Avalonia.Input.Raw;
+using Avalonia.Rendering;
 using Avalonia.Threading;
 using Avalonia.Win32.Automation;
 using Avalonia.Win32.Automation.Interop;
@@ -873,6 +875,9 @@ namespace Avalonia.Win32
                 case WindowsMessage.WM_DISPLAYCHANGE:
                     {
                         Screen?.OnChanged();
+
+                        Win32Platform.UpdateTimerFps();
+
                         return IntPtr.Zero;
                     }