//C++ header - Open Scene Graph - Copyright (C) 1998-2001 Robert Osfield
//Distributed under the terms of the GNU Library General Public License (LGPL)
//as published by the Free Software Foundation.

#ifndef OSGUTIL_VISUALSREQUIREMENTSVISITOR
#define OSGUTIL_VISUALSREQUIREMENTSVISITOR 1

#include <osg/NodeVisitor>
#include <osg/Geode>
#include <osg/VisualsSettings>

#include <osgUtil/Export>

namespace osgUtil {

/** A visitor for traversing a scene graph establishing the OpenGL visuals are required
  * to support rendering of that scene graph.  The results can then be used by
  * applications to set up there windows with the correct visuals.  Have a look at
  * src/osgGLUT/Viewer.cpp's Viewer::open() method for an example how to use it.
  */
class OSGUTIL_EXPORT VisualsRequirementsVisitor : public osg::NodeVisitor
{
    public:

        /** Default to traversing all children, and reqiresDoubleBuffer,
          * requiresRGB and requiresDepthBuffer to true and with
          * alpha and stencil off.*/
        VisualsRequirementsVisitor();
        

        /** Set the VisualsSettings. */
        inline void setVisualsSettings(osg::VisualsSettings* vs) { _vs = vs; }
        
        /** Get the VisualsSettings */
        inline const osg::VisualsSettings* getVisualsSettings() const { return _vs.get(); }
        
        virtual void applyStateSet(osg::StateSet& stateset);

        virtual void apply(osg::Node& node);

        virtual void apply(osg::Geode& geode);

        virtual void apply(osg::Impostor& impostor);
        
    protected:
    
        osg::ref_ptr<osg::VisualsSettings> _vs;
    
};

};

#endif