source: code/trunk/src/external/bullet/BulletCollision/CollisionShapes/btTriangleInfoMap.h @ 10007

/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2010 Erwin Coumans  http://bulletphysics.org

This software is provided 'as-is', without any express or implied warranty.
In no event will the authors be held liable for any damages arising from the use of this software.
Permission is granted to anyone to use this software for any purpose, 
including commercial applications, and to alter it and redistribute it freely, 
subject to the following restrictions:

1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/

#ifndef _BT_TRIANGLE_INFO_MAP_H
#define _BT_TRIANGLE_INFO_MAP_H


#include "LinearMath/btHashMap.h"
#include "LinearMath/btSerializer.h"


///for btTriangleInfo m_flags
#define TRI_INFO_V0V1_CONVEX 1
#define TRI_INFO_V1V2_CONVEX 2
#define TRI_INFO_V2V0_CONVEX 4

#define TRI_INFO_V0V1_SWAP_NORMALB 8
#define TRI_INFO_V1V2_SWAP_NORMALB 16
#define TRI_INFO_V2V0_SWAP_NORMALB 32


///The btTriangleInfo structure stores information to adjust collision normals to avoid collisions against internal edges
///it can be generated using 
struct  btTriangleInfo
{
        btTriangleInfo()
        {
                m_edgeV0V1Angle = SIMD_2_PI;
                m_edgeV1V2Angle = SIMD_2_PI;
                m_edgeV2V0Angle = SIMD_2_PI;
                m_flags=0;
        }

        int                     m_flags;

        btScalar        m_edgeV0V1Angle;
        btScalar        m_edgeV1V2Angle;
        btScalar        m_edgeV2V0Angle;

};

typedef btHashMap<btHashInt,btTriangleInfo> btInternalTriangleInfoMap;


///The btTriangleInfoMap stores edge angle information for some triangles. You can compute this information yourself or using btGenerateInternalEdgeInfo.
struct  btTriangleInfoMap : public btInternalTriangleInfoMap
{
        btScalar        m_convexEpsilon;///used to determine if an edge or contact normal is convex, using the dot product
        btScalar        m_planarEpsilon; ///used to determine if a triangle edge is planar with zero angle
        btScalar        m_equalVertexThreshold; ///used to compute connectivity: if the distance between two vertices is smaller than m_equalVertexThreshold, they are considered to be 'shared'
        btScalar        m_edgeDistanceThreshold; ///used to determine edge contacts: if the closest distance between a contact point and an edge is smaller than this distance threshold it is considered to "hit the edge"
        btScalar        m_maxEdgeAngleThreshold; //ignore edges that connect triangles at an angle larger than this m_maxEdgeAngleThreshold
        btScalar        m_zeroAreaThreshold; ///used to determine if a triangle is degenerate (length squared of cross product of 2 triangle edges < threshold)
        
        
        btTriangleInfoMap()
        {
                m_convexEpsilon = 0.00f;
                m_planarEpsilon = 0.0001f;
                m_equalVertexThreshold = btScalar(0.0001)*btScalar(0.0001);
                m_edgeDistanceThreshold = btScalar(0.1);
                m_zeroAreaThreshold = btScalar(0.0001)*btScalar(0.0001);
                m_maxEdgeAngleThreshold = SIMD_2_PI;
        }
        virtual ~btTriangleInfoMap() {}

        virtual int     calculateSerializeBufferSize() const;

        ///fills the dataBuffer and returns the struct name (and 0 on failure)
        virtual const char*     serialize(void* dataBuffer, btSerializer* serializer) const;

        void    deSerialize(struct btTriangleInfoMapData& data);

};

struct  btTriangleInfoData
{
        int                     m_flags;
        float   m_edgeV0V1Angle;
        float   m_edgeV1V2Angle;
        float   m_edgeV2V0Angle;
};

struct  btTriangleInfoMapData
{
        int                                     *m_hashTablePtr;
        int                                     *m_nextPtr;
        btTriangleInfoData      *m_valueArrayPtr;
        int                                     *m_keyArrayPtr;

        float   m_convexEpsilon;
        float   m_planarEpsilon;
        float   m_equalVertexThreshold; 
        float   m_edgeDistanceThreshold;
        float   m_zeroAreaThreshold;

        int             m_nextSize;
        int             m_hashTableSize;
        int             m_numValues;
        int             m_numKeys;
        char    m_padding[4];
};

SIMD_FORCE_INLINE       int     btTriangleInfoMap::calculateSerializeBufferSize() const
{
        return sizeof(btTriangleInfoMapData);
}

///fills the dataBuffer and returns the struct name (and 0 on failure)
SIMD_FORCE_INLINE       const char*     btTriangleInfoMap::serialize(void* dataBuffer, btSerializer* serializer) const
{
        btTriangleInfoMapData* tmapData = (btTriangleInfoMapData*) dataBuffer;
        tmapData->m_convexEpsilon = m_convexEpsilon;
        tmapData->m_planarEpsilon = m_planarEpsilon;
        tmapData->m_equalVertexThreshold = m_equalVertexThreshold;
        tmapData->m_edgeDistanceThreshold = m_edgeDistanceThreshold;
        tmapData->m_zeroAreaThreshold = m_zeroAreaThreshold;
        
        tmapData->m_hashTableSize = m_hashTable.size();

        tmapData->m_hashTablePtr = tmapData->m_hashTableSize ? (int*)serializer->getUniquePointer((void*)&m_hashTable[0]) : 0;
        if (tmapData->m_hashTablePtr)
        { 
                //serialize an int buffer
                int sz = sizeof(int);
                int numElem = tmapData->m_hashTableSize;
                btChunk* chunk = serializer->allocate(sz,numElem);
                int* memPtr = (int*)chunk->m_oldPtr;
                for (int i=0;i<numElem;i++,memPtr++)
                {
                        *memPtr = m_hashTable[i];
                }
                serializer->finalizeChunk(chunk,"int",BT_ARRAY_CODE,(void*)&m_hashTable[0]);

        }

        tmapData->m_nextSize = m_next.size();
        tmapData->m_nextPtr = tmapData->m_nextSize? (int*)serializer->getUniquePointer((void*)&m_next[0]): 0;
        if (tmapData->m_nextPtr)
        {
                int sz = sizeof(int);
                int numElem = tmapData->m_nextSize;
                btChunk* chunk = serializer->allocate(sz,numElem);
                int* memPtr = (int*)chunk->m_oldPtr;
                for (int i=0;i<numElem;i++,memPtr++)
                {
                        *memPtr = m_next[i];
                }
                serializer->finalizeChunk(chunk,"int",BT_ARRAY_CODE,(void*)&m_next[0]);
        }
        
        tmapData->m_numValues = m_valueArray.size();
        tmapData->m_valueArrayPtr = tmapData->m_numValues ? (btTriangleInfoData*)serializer->getUniquePointer((void*)&m_valueArray[0]): 0;
        if (tmapData->m_valueArrayPtr)
        {
                int sz = sizeof(btTriangleInfoData);
                int numElem = tmapData->m_numValues;
                btChunk* chunk = serializer->allocate(sz,numElem);
                btTriangleInfoData* memPtr = (btTriangleInfoData*)chunk->m_oldPtr;
                for (int i=0;i<numElem;i++,memPtr++)
                {
                        memPtr->m_edgeV0V1Angle = m_valueArray[i].m_edgeV0V1Angle;
                        memPtr->m_edgeV1V2Angle = m_valueArray[i].m_edgeV1V2Angle;
                        memPtr->m_edgeV2V0Angle = m_valueArray[i].m_edgeV2V0Angle;
                        memPtr->m_flags = m_valueArray[i].m_flags;
                }
                serializer->finalizeChunk(chunk,"btTriangleInfoData",BT_ARRAY_CODE,(void*) &m_valueArray[0]);
        }
        
        tmapData->m_numKeys = m_keyArray.size();
        tmapData->m_keyArrayPtr = tmapData->m_numKeys ? (int*)serializer->getUniquePointer((void*)&m_keyArray[0]) : 0;
        if (tmapData->m_keyArrayPtr)
        {
                int sz = sizeof(int);
                int numElem = tmapData->m_numValues;
                btChunk* chunk = serializer->allocate(sz,numElem);
                int* memPtr = (int*)chunk->m_oldPtr;
                for (int i=0;i<numElem;i++,memPtr++)
                {
                        *memPtr = m_keyArray[i].getUid1();
                }
                serializer->finalizeChunk(chunk,"int",BT_ARRAY_CODE,(void*) &m_keyArray[0]);

        }
        return "btTriangleInfoMapData";
}



///fills the dataBuffer and returns the struct name (and 0 on failure)
SIMD_FORCE_INLINE       void    btTriangleInfoMap::deSerialize(btTriangleInfoMapData& tmapData )
{


        m_convexEpsilon = tmapData.m_convexEpsilon;
        m_planarEpsilon = tmapData.m_planarEpsilon;
        m_equalVertexThreshold = tmapData.m_equalVertexThreshold;
        m_edgeDistanceThreshold = tmapData.m_edgeDistanceThreshold;
        m_zeroAreaThreshold = tmapData.m_zeroAreaThreshold;
        m_hashTable.resize(tmapData.m_hashTableSize);
        int i =0;
        for (i=0;i<tmapData.m_hashTableSize;i++)
        {
                m_hashTable[i] = tmapData.m_hashTablePtr[i];
        }
        m_next.resize(tmapData.m_nextSize);
        for (i=0;i<tmapData.m_nextSize;i++)
        {
                m_next[i] = tmapData.m_nextPtr[i];
        }
        m_valueArray.resize(tmapData.m_numValues);
        for (i=0;i<tmapData.m_numValues;i++)
        {
                m_valueArray[i].m_edgeV0V1Angle = tmapData.m_valueArrayPtr[i].m_edgeV0V1Angle;
                m_valueArray[i].m_edgeV1V2Angle = tmapData.m_valueArrayPtr[i].m_edgeV1V2Angle;
                m_valueArray[i].m_edgeV2V0Angle = tmapData.m_valueArrayPtr[i].m_edgeV2V0Angle;
                m_valueArray[i].m_flags = tmapData.m_valueArrayPtr[i].m_flags;
        }
        
        m_keyArray.resize(tmapData.m_numKeys,btHashInt(0));
        for (i=0;i<tmapData.m_numKeys;i++)
        {
                m_keyArray[i].setUid1(tmapData.m_keyArrayPtr[i]);
        }
}


#endif //_BT_TRIANGLE_INFO_MAP_H