From eef4801ba7f8096921338eb6734f518e6e39c860 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Fri, 27 Feb 2009 11:11:06 +0000
Subject: [PATCH] From Roland Smeenk, "Attached is a small bug fix for the
 redundant messages that are created in OSG applications on windows.
 GraphicsWindowWin32::setCursor is called every frame from the WM_NCHITTEST
 message. This will result in a call to ::SetCursor(_currentCursor) every
 frame, which again causes a WM_MOUSEMOVE to occur. The fix exits
 GraphicsWindowWin32::setCursor if the requested cursor already is the current
 cursor.

"
---
 src/osgViewer/GraphicsWindowWin32.cpp | 37 +++++++++++++++------------
 1 file changed, 20 insertions(+), 17 deletions(-)

diff --git a/src/osgViewer/GraphicsWindowWin32.cpp b/src/osgViewer/GraphicsWindowWin32.cpp
index 9613b2a15..525b69036 100644
--- a/src/osgViewer/GraphicsWindowWin32.cpp
+++ b/src/osgViewer/GraphicsWindowWin32.cpp
@@ -1935,25 +1935,28 @@ void GraphicsWindowWin32::useCursor( bool cursorOn )
 
 void GraphicsWindowWin32::setCursor( MouseCursor mouseCursor )
 {
-    if (mouseCursor != LeftRightCursor && 
-        mouseCursor != UpDownCursor && 
-        mouseCursor != TopLeftCorner && 
-        mouseCursor != TopRightCorner && 
-        mouseCursor != BottomLeftCorner && 
-        mouseCursor != BottomRightCorner)
+    if (_mouseCursor != mouseCursor)
     {
-        _appMouseCursor = mouseCursor;
+        if (mouseCursor != LeftRightCursor && 
+            mouseCursor != UpDownCursor && 
+            mouseCursor != TopLeftCorner && 
+            mouseCursor != TopRightCorner && 
+            mouseCursor != BottomLeftCorner && 
+            mouseCursor != BottomRightCorner)
+        {
+            _appMouseCursor = mouseCursor;
+        }
+
+        _mouseCursor = mouseCursor;
+        HCURSOR newCursor = getOrCreateCursor( mouseCursor);
+        if (newCursor == _currentCursor) return;
+
+        _currentCursor = newCursor;
+        _traits->useCursor = (_currentCursor != NULL);
+
+        if (_mouseCursor != InheritCursor)
+            ::SetCursor(_currentCursor);
     }
-
-    _mouseCursor = mouseCursor;
-    HCURSOR newCursor = getOrCreateCursor( mouseCursor);
-    if (newCursor == _currentCursor) return;
-
-    _currentCursor = newCursor;
-    _traits->useCursor = (_currentCursor != NULL);
-
-    if (_mouseCursor != InheritCursor)
-        ::SetCursor(_currentCursor);
 }
 
 HCURSOR GraphicsWindowWin32::getOrCreateCursor(MouseCursor mouseCursor)