OgreProgressiveMesh.h

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/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2011 Torus Knot Software Ltd

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
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copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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THE SOFTWARE.
-----------------------------------------------------------------------------
*/
// The underlying algorithms in this class are based heavily on:
/*
 *  Progressive Mesh type Polygon Reduction Algorithm
 *  by Stan Melax (c) 1998
 */

#ifndef __ProgressiveMesh_H_
#define __ProgressiveMesh_H_

#include "OgrePrerequisites.h"
#include "OgreVector3.h"
#include "OgreHardwareVertexBuffer.h"
#include "OgreHardwareIndexBuffer.h"
#include "OgreRenderOperation.h"

namespace Ogre {

    class _OgreExport ProgressiveMesh : public ProgMeshAlloc
    {
    public:

        enum VertexReductionQuota
        {
            VRQ_CONSTANT,
            VRQ_PROPORTIONAL
        };

        typedef vector<IndexData*>::type LODFaceList;

        ProgressiveMesh(const VertexData* vertexData, const IndexData* indexData);
        virtual ~ProgressiveMesh();

        virtual void addExtraVertexPositionBuffer(const VertexData* vertexData);

        virtual void build(ushort numLevels, LODFaceList* outList, 
            VertexReductionQuota quota = VRQ_PROPORTIONAL, Real reductionValue = 0.5f );

    protected:
        const VertexData *mpVertexData;
        const IndexData *mpIndexData;

        size_t mCurrNumIndexes;
        size_t mNumCommonVertices;

        // Internal classes
        class PMTriangle;
        class PMVertex;

        public: // VC6 hack

        class _OgrePrivate PMFaceVertex {
        public:
            size_t realIndex;
            PMVertex* commonVertex;
        };

        protected:

        class _OgrePrivate PMTriangle {
        public:
            PMTriangle();
            void setDetails(size_t index, PMFaceVertex *v0, PMFaceVertex *v1, PMFaceVertex *v2);
            void computeNormal(void);
            void replaceVertex(PMFaceVertex *vold, PMFaceVertex *vnew);
            bool hasCommonVertex(PMVertex *v) const;
            bool hasFaceVertex(PMFaceVertex *v) const;
            PMFaceVertex* getFaceVertexFromCommon(PMVertex* commonVert);
            void notifyRemoved(void);

            PMFaceVertex* vertex[3]; // the 3 points that make this tri
            Vector3   normal;    // unit vector orthogonal to this face
            bool      removed;   // true if this tri is now removed
            size_t index;
        };

        class _OgrePrivate PMVertex {
        public:
            PMVertex();
            void setDetails(const Vector3& v, size_t index);
            void removeIfNonNeighbor(PMVertex *n);
            bool isBorder(void);
            bool isManifoldEdgeWith(PMVertex* v); // is edge this->src a manifold edge?
            void notifyRemoved(void);

            Vector3  position;  // location of point in euclidean space
            size_t index;       // place of vertex in original list
            typedef set<PMVertex *>::type NeighborList;
            typedef set<PMVertex *>::type DuplicateList;
            NeighborList neighbor; // adjacent vertices
            typedef set<PMTriangle *>::type FaceList;
            FaceList face;     // adjacent triangles

            Real collapseCost;  // cached cost of collapsing edge
            PMVertex * collapseTo; // candidate vertex for collapse
            bool      removed;   // true if this vert is now removed
            bool      toBeRemoved; // denug

            bool seam;  

        };

        typedef vector<PMTriangle>::type TriangleList;
        typedef vector<PMFaceVertex>::type FaceVertexList;
        typedef vector<PMVertex>::type CommonVertexList;
        typedef vector<Real>::type WorstCostList;

        struct PMWorkingData
        {
            TriangleList mTriList; 
            FaceVertexList mFaceVertList; // The vertex details referenced by the triangles
            CommonVertexList mVertList; // The master list of common vertices
        };

        typedef vector<PMWorkingData>::type WorkingDataList;
        WorkingDataList mWorkingData;

        WorstCostList mWorstCosts;

        void addWorkingData(const VertexData* vertexData, const IndexData* indexData);

        void initialiseEdgeCollapseCosts(void);
        Real computeEdgeCollapseCost(PMVertex *src, PMVertex *dest);
        Real computeEdgeCostAtVertexForBuffer(WorkingDataList::iterator idata, size_t vertIndex);
        void computeEdgeCostAtVertex(size_t vertIndex);
        void computeAllCosts(void);
        size_t getNextCollapser(void);
        void bakeNewLOD(IndexData* pData);

        void collapse(PMVertex *collapser);

        void dumpContents(const String& log);









    };


}

#endif