From 7c5802efcfbbbf27a6f1a437b27ee2f3f1a9a85b Mon Sep 17 00:00:00 2001
From: ahopper <alan@samsararesearch.com>
Date: Tue, 20 Nov 2018 22:12:55 +0000
Subject: [PATCH] change name and check invalidate rect

---
 src/Avalonia.Controls/TopLevel.cs    |  6 +++---
 src/Avalonia.Input/IPointerDevice.cs |  2 +-
 src/Avalonia.Input/MouseDevice.cs    | 19 ++++++++++++-------
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/src/Avalonia.Controls/TopLevel.cs b/src/Avalonia.Controls/TopLevel.cs
index 082fc8858d..10419131eb 100644
--- a/src/Avalonia.Controls/TopLevel.cs
+++ b/src/Avalonia.Controls/TopLevel.cs
@@ -230,7 +230,7 @@ namespace Avalonia.Controls
         void IRenderRoot.Invalidate(Rect rect)
         {
             PlatformImpl?.Invalidate(rect);
-            UpdatePointerOver();
+            UpdatePointerOver(rect);
         }
         
         /// <inheritdoc/>
@@ -351,9 +351,9 @@ namespace Avalonia.Controls
             _inputManager.ProcessInput(e);
         }
 
-        private void UpdatePointerOver()
+        private void UpdatePointerOver(Rect rect)
         {
-            (this as IInputRoot).MouseDevice.LayoutUpdated(this);
+            (this as IInputRoot).MouseDevice.SceneInvalidated(this, rect);
         }
     }
 }
diff --git a/src/Avalonia.Input/IPointerDevice.cs b/src/Avalonia.Input/IPointerDevice.cs
index d7e7077429..932cbc989f 100644
--- a/src/Avalonia.Input/IPointerDevice.cs
+++ b/src/Avalonia.Input/IPointerDevice.cs
@@ -13,6 +13,6 @@ namespace Avalonia.Input
 
         Point GetPosition(IVisual relativeTo);
 
-        void LayoutUpdated(IInputRoot root);
+        void SceneInvalidated(IInputRoot root, Rect rect);
     }
 }
diff --git a/src/Avalonia.Input/MouseDevice.cs b/src/Avalonia.Input/MouseDevice.cs
index 916827775a..a4f0020ea3 100644
--- a/src/Avalonia.Input/MouseDevice.cs
+++ b/src/Avalonia.Input/MouseDevice.cs
@@ -104,16 +104,21 @@ namespace Avalonia.Input
                 ProcessRawEvent(margs);
         }
 
-        public void LayoutUpdated(IInputRoot root)
+        public void SceneInvalidated(IInputRoot root, Rect rect)
         {
-            if (Captured == null)
+            var clientPoint = root.PointToClient(Position);
+
+            if (rect.Contains(clientPoint))
             {
-                SetPointerOver(this, root, root.PointToClient(Position));    
+                if (Captured == null)
+                {
+                    SetPointerOver(this, root, clientPoint);
+                }
+                else
+                {
+                    SetPointerOver(this, root, Captured);
+                }
             }
-            else
-            {
-                SetPointerOver(this, root, Captured);               
-            }                   
         }
 
         private void ProcessRawEvent(RawMouseEventArgs e)