From Marius Heise, "here is a patch that implements Win32 HW-synced swapping using wglJoinSwapGroupNV, wglBindSwapBarrierNV and the existing traits. It was tested with multiple ATI FirePro S400 cards.

I also fixed the vsync implementation introduced with rev.11357 that was crashing with the Windows Error #170. So I removed your temporary /* */ around the vsync condition..."

include/osg/GraphicsContext

@@ -108,6 +108,11 @@ class OSG_EXPORT GraphicsContext : public Object
             // V-sync
             bool            vsync;
             
+            // Swap Group
+            bool            swapGroupEnabled;
+            GLuint          swapGroup;
+            GLuint          swapBarrier;
+
             // use multithreaded OpenGL-engine (OS X only)
             bool            useMultiThreadedOpenGLEngine;
             

include/osgViewer/GraphicsWindow

@@ -145,6 +145,14 @@ class OSGVIEWER_EXPORT GraphicsWindow : public osg::GraphicsContext, public osgG
 
         bool getSyncToVBlank() const { return _traits.valid() ? _traits->vsync : true; }
 
+        /** Set swap group. */
+        virtual void setSwapGroup(bool on, GLuint group, GLuint barrier)
+        {
+            osg::notify(osg::NOTICE) << "GraphicsWindow::setSwapGroup(" << on << " " << group << " " << barrier << ") not implemented." << std::endl;
+        }
+
+        void getSwapGroup(bool& on, GLuint& group, GLuint& barrier) const { on = _traits->swapGroupEnabled; group = _traits->swapGroup; barrier = _traits->swapBarrier; }
+
     public:
 
         /** Return whether a valid and usable GraphicsContext has been created.*/

include/osgViewer/api/Win32/GraphicsWindowWin32

@@ -90,6 +90,9 @@ class OSGVIEWER_EXPORT GraphicsWindowWin32 : public osgViewer::GraphicsWindow, p
         /** Set sync-to-vblank. */
         virtual void setSyncToVBlank(bool on);
 
+        /** Set swap group. */
+        virtual void setSwapGroup(bool on, GLuint group, GLuint barrier);
+
         /** Handle a native (Win32) windowing event as received from the system */
         virtual LRESULT handleNativeWindowingEvent( HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam );