Added support for X11's overrideRedirect functionality

include/osg/GraphicsContext

@@ -92,7 +92,8 @@ class OSG_EXPORT GraphicsContext : public Object
                 useMultiThreadedOpenGLEngine(false),
                 useCursor(true),
                 sharedContext(0),
-                setInheritedWindowPixelFormat(false) {}
+                setInheritedWindowPixelFormat(false),
+                overrideRedirect(false) {}
                             
             // graphics context original and size
             int x;
@@ -145,6 +146,9 @@ class OSG_EXPORT GraphicsContext : public Object
             
             // ask the GraphicsWindow implementation to set the pixel format of an inherited window
             bool setInheritedWindowPixelFormat;
+            
+            // X11 hint whether to override the window managers window size/position redirection
+            bool overrideRedirect;
         };
     
     

src/osgPlugins/cfg/ReaderWriterCFG.cpp

@@ -84,6 +84,8 @@ static osg::GraphicsContext::Traits* buildTrait(RenderSurface& rs)
     traits->sharedContext = 0;
     traits->pbuffer = (rs.getDrawableType()==osgProducer::RenderSurface::DrawableType_PBuffer);
 
+    traits->overrideRedirect = rs.usesOverrideRedirect();
+
     return traits;
  }
 

src/osgViewer/GraphicsWindowX11.cpp

@@ -655,11 +655,12 @@ bool GraphicsWindowX11::createWindow()
     swatt.event_mask =  0;
     unsigned long mask = CWBackPixel | CWBorderPixel | CWEventMask | CWColormap;
 
-    bool overrideRedirect = false;
-    if (overrideRedirect)
+    if (_traits->overrideRedirect)
     {
         swatt.override_redirect = true;
         mask |= CWOverrideRedirect;
+        
+        osg::notify(osg::NOTICE)<<"Setting override redirect"<<std::endl;
     }
 
     _window = XCreateWindow( _display, _parent,