/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield 
 *
 * This library is open source and may be redistributed and/or modified under  
 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or 
 * (at your option) any later version.  The full license is in LICENSE file
 * included with this distribution, and on the openscenegraph.org website.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 * OpenSceneGraph Public License for more details.
*/

#ifndef OSGTERRAIN_TERRAINTECHNIQUE
#define OSGTERRAIN_TERRAINTECHNIQUE 1

#include <osg/Object>

#include <osgUtil/UpdateVisitor>
#include <osgUtil/CullVisitor>

#include <osgTerrain/Export>

namespace osgTerrain {

class TerrainTile;

class OSGTERRAIN_EXPORT TerrainTechnique : public osg::Object
{
    public:

        TerrainTechnique();

        /** Copy constructor using CopyOp to manage deep vs shallow copy.*/
        TerrainTechnique(const TerrainTechnique&,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY);
        
        META_Object(osgTerrain, TerrainTechnique);

        TerrainTile* getTerrainTile() { return _terrainTile; }
        const TerrainTile* getTerrainTile() const { return _terrainTile; }

        virtual void init();

        virtual void update(osgUtil::UpdateVisitor* nv);

        virtual void cull(osgUtil::CullVisitor* nv);

        /** Clean scene graph from any terrain technique specific nodes.*/
        virtual void cleanSceneGraph();

        /** Traverse the terrain subgraph.*/
        virtual void traverse(osg::NodeVisitor& nv);

        /** Dirty so that cached data structures will be updated on next use.*/
        virtual void dirty();

        /** Return true if cached data structures need updating.*/
        virtual bool isDirty() const { return _dirty; }

    protected:

        virtual ~TerrainTechnique();
        
        friend class osgTerrain::TerrainTile;

        TerrainTile*    _terrainTile;
        bool            _dirty;

};

}

#endif