update

Runtime/engine/WidgetCanvas.cs

         private Texture _texture;
         private Vector2 _lastMouseMove;
         private bool _mouseEntered;
-
+        private static Event _repaintEvent;
+            if (_repaintEvent == null) {
+                _repaintEvent = new Event() { type = EventType.Repaint };
+            }
 
             if (_windowAdapter == null)
             {
             {
                 this._windowAdapter.Update();
             }
-            this._windowAdapter.OnGUI(new Event() {type=EventType.Repaint});
+            this._windowAdapter.OnGUI(_repaintEvent);
         }
 
          private void OnGUI()