/*  -*-c++-*- 
 *  Copyright (C) 2009 Cedric Pinson <cedric.pinson@plopbyte.net>
 *
 * 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 OSGANIMATION_RIG_TRANSFORM_HARDWARE
#define OSGANIMATION_RIG_TRANSFORM_HARDWARE 1

#include <osgAnimation/Export>
#include <osgAnimation/RigTransform>
#include <osgAnimation/VertexInfluence>
#include <osgAnimation/Bone>
#include <osg/Matrix>
#include <osg/Array>

namespace osgAnimation 
{
    class RigGeometry;

    /// This class manage format for hardware skinning
    class OSGANIMATION_EXPORT RigTransformHardware : public RigTransform
    {
    public:
        typedef osg::Matrix MatrixType;
        typedef osgAnimation::Bone BoneType;
        typedef std::vector<osg::ref_ptr<osg::Vec4Array> > BoneWeightAttribList;
        typedef std::vector<osg::ref_ptr<BoneType> > BonePalette;

        typedef std::vector<osg::Matrix> MatrixPalette;
        struct IndexWeightEntry
        {
            int _boneIndex;
            float _boneWeight;
            IndexWeightEntry() { _boneIndex = 0; _boneWeight = 0;}
            IndexWeightEntry(int index, float weight) { _boneIndex = index; _boneWeight = weight;}
            int getIndex() const { return _boneIndex; }
            float getWeight() const { return _boneWeight; }
        };
        typedef std::vector<std::vector<IndexWeightEntry> > VertexIndexWeightList;

        RigTransformHardware();

        osg::Vec4Array* getVertexAttrib(int index);
        int getNumVertexAttrib();

        osg::Uniform* getMatrixPaletteUniform();
        void computeMatrixPaletteUniform(const osg::Matrix& transformFromSkeletonToGeometry, const osg::Matrix& invTransformFromSkeletonToGeometry);

        int getNumBonesPerVertex() const;
        int getNumVertexes() const;

        bool createPalette(int nbVertexes, BoneMap boneMap, const VertexInfluenceSet::VertexIndexToBoneWeightMap& vertexIndexToBoneWeightMap);

        virtual void operator()(RigGeometry&);
        void setShader(osg::Shader*);

    protected:

        bool init(RigGeometry&);

        BoneWeightAttribList createVertexAttribList();
        osg::Uniform* createVertexUniform();

        int _bonesPerVertex;
        int _nbVertexes;
        VertexIndexWeightList _vertexIndexMatrixWeightList;
        BonePalette _bonePalette;
        BoneWeightAttribList _boneWeightAttribArrays;
        osg::ref_ptr<osg::Uniform> _uniformMatrixPalette;
        osg::ref_ptr<osg::Shader> _shader;

        bool _needInit;
    };
}

#endif