From Daniel Sjölie, support for controlling which viewports are focusable i.e.

recive mouse/keyboard events.

include/osgGLUT/Viewer

@@ -93,6 +93,10 @@ class OSGGLUT_EXPORT Viewer : public Window, public osgGA::GUIActionAdapter
         void selectCameraManipulator(unsigned int pos, 
 				     unsigned int viewport = 0);
 
+	/// Set focusable
+	void setFocusable( unsigned int viewp, bool focusable )
+	{ _viewportList[viewp]._focusable = focusable; };
+
         void prependEventHandler(osgGA::GUIEventHandler* handler,unsigned int viewport = 0);
         void appendEventHandler(osgGA::GUIEventHandler* handler,unsigned int viewport = 0);
 
@@ -147,6 +151,8 @@ class OSGGLUT_EXPORT Viewer : public Window, public osgGA::GUIActionAdapter
             osg::ref_ptr<osgUtil::SceneView> sceneView;
             float viewport[4];                        // Win-size-relative [0,1]
 
+	    bool _focusable;
+
             osg::ref_ptr<osgGA::CameraManipulator>      _cameraManipulator;
             CameraManipList                             _cameraManipList;
             

src/osgGLUT/Viewer.cpp

@@ -854,7 +854,9 @@ void Viewer::mouse(int button, int state, int x, int y)
          mask == osgGA::GUIEventAdapter::RIGHT_MOUSE_BUTTON))
     {
         int focus = mapWindowXYToViewport(x,y);
-        if (focus >= 0 && focus != int(_focusedViewport))
+        if (focus >= 0
+                && _viewportList[(unsigned int)focus]._focusable
+                && focus != int(_focusedViewport))
           setFocusedViewport(focus);
     }