- direct3d: try Vista workaround documented in VirtualDub blog

modules/video_output/directx/direct3d.c

@@ -582,7 +582,23 @@ static void Display( vout_thread_t *p_vout, picture_t *p_pic )
     /* if set, remove the black brush to avoid flickering in repaint operations */
     if( 0UL != GetClassLong( p_vout->p_sys->hvideownd, GCL_HBRBACKGROUND) )
     {
+        OSVERSIONINFO winVer;
+        winVer.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
+
         SetClassLong( p_vout->p_sys->hvideownd, GCL_HBRBACKGROUND, 0UL);
+        /*
+        ** According to virtual dub blog, Vista has problems rendering 3D child windows
+        ** created by a different thread than its parent. Try the workaround in
+        ** http://www.virtualdub.org/blog/pivot/entry.php?id=149
+        */
+        if( GetVersionEx(&winVer) )
+        {
+            if( winVer.dwMajorVersion > 5 )
+            {
+                SetWindowPos( p_vout->p_sys->hvideownd, 0, 0, 0, 0, 0,
+                              SWP_NOMOVE|SWP_NOSIZE|SWP_NOZORDER|SWP_FRAMECHANGED);
+            }
+        }
     }
 }