Fix Avalonia Native MouseWheel-Support (ryubing/ryujinx!116)

See merge request ryubing/ryujinx!116

src/Ryujinx/Input/AvaloniaMouseDriver.cs

@@ -1,6 +1,7 @@
 using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Input;
+using Avalonia.Threading;
 using Ryujinx.Input;
 using System;
 using System.Collections.Generic;
@@ -16,6 +17,8 @@ namespace Ryujinx.Ava.Input
         private bool _isDisposed;
         private Size _size;
         private readonly TopLevel _window;
+        private DispatcherTimer _scrollStopTimer;
+        private const int _dispatchTimerMS = 100;
 
         public bool[] PressedButtons { get; }
         public Vector2 CurrentPosition { get; private set; }
@@ -39,6 +42,11 @@ namespace Ryujinx.Ava.Input
             _window.PointerReleased += Parent_PointerReleasedEvent;
             _window.PointerWheelChanged += Parent_PointerWheelChanged;
 
+            _scrollStopTimer = new DispatcherTimer
+            {
+                Interval = TimeSpan.FromMilliseconds(_dispatchTimerMS)
+            };
+
             PressedButtons = new bool[(int)MouseButton.Count];
 
             _size = new Size((int)parent.Bounds.Width, (int)parent.Bounds.Height);
@@ -62,10 +70,26 @@ namespace Ryujinx.Ava.Input
         {
             _size = new Size((int)rect.Width, (int)rect.Height);
         }
+        
+        private void HandleScrollStopped() 
+        {
+            Scroll = new Vector2(0, 0);
+        }
 
         private void Parent_PointerWheelChanged(object o, PointerWheelEventArgs args)
         {
             Scroll = new Vector2((float)args.Delta.X, (float)args.Delta.Y);
+
+            _scrollStopTimer?.Stop();
+
+            _scrollStopTimer.Tick += (_, __) =>
+            {
+                _scrollStopTimer.Stop();
+
+                HandleScrollStopped();
+
+            };
+            _scrollStopTimer.Start();
         }
 
         private void Parent_PointerReleasedEvent(object o, PointerReleasedEventArgs args)