/* -*-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 OSGSHADOW_SHADOWETEXTURE
#define OSGSHADOW_SHADOWETEXTURE 1

#include <osg/Camera>
#include <osg/Material>

#include <osgShadow/ShadowTechnique>

namespace osgShadow {

/** ShadowedTexture provides an implementation of shadow textures.*/
class OSGSHADOW_EXPORT ShadowTexture : public ShadowTechnique
{
    public :
        ShadowTexture();

        ShadowTexture(const ShadowTexture& es, const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY);

        META_Object(osgShadow, ShadowTexture);

        /** Set the texture unit that the shadow texture will be applied on.*/
        void setTextureUnit(unsigned int unit);

        /** Get the texture unit that the shadow texture will be applied on.*/
        unsigned int getTextureUnit() const { return _textureUnit; }


        /** initialize the ShadowedScene and local cached data structures.*/
        virtual void init();

        /** run the update traversal of the ShadowedScene and update any loca chached data structures.*/
        virtual void update(osg::NodeVisitor& nv);

        /** run the cull traversal of the ShadowedScene and set up the rendering for this ShadowTechnique.*/
        virtual void cull(osgUtil::CullVisitor& cv);

        /** Clean scene graph from any shadow technique specific nodes, state and drawables.*/
        virtual void cleanSceneGraph();


        /** Resize any per context GLObject buffers to specified size. */
        virtual void resizeGLObjectBuffers(unsigned int maxSize);

        /** If State is non-zero, this function releases any associated OpenGL objects for
           * the specified graphics context. Otherwise, releases OpenGL objects
           * for all graphics contexts. */
        virtual void releaseGLObjects(osg::State* = 0) const;

    protected :

        virtual ~ShadowTexture() {}

        osg::ref_ptr<osg::Camera>       _camera;
        osg::ref_ptr<osg::TexGen>       _texgen;
        osg::ref_ptr<osg::Texture2D>    _texture;
        osg::ref_ptr<osg::StateSet>     _stateset;
        osg::ref_ptr<osg::Material>     _material;
        unsigned int                    _textureUnit;
};

}

#endif
