btQuantizedBvh.h

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/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/

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 QUANTIZED_BVH_H
#define QUANTIZED_BVH_H

//#define DEBUG_CHECK_DEQUANTIZATION 1
#ifdef DEBUG_CHECK_DEQUANTIZATION
#ifdef __SPU__
#define printf spu_printf
#endif //__SPU__

#include <stdio.h>
#include <stdlib.h>
#endif //DEBUG_CHECK_DEQUANTIZATION

#include "LinearMath/btVector3.h"
#include "LinearMath/btAlignedAllocator.h"


//http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vclang/html/vclrf__m128.asp


//Note: currently we have 16 bytes per quantized node
#define MAX_SUBTREE_SIZE_IN_BYTES  2048

// 10 gives the potential for 1024 parts, with at most 2^21 (2097152) (minus one
// actually) triangles each (since the sign bit is reserved
#define MAX_NUM_PARTS_IN_BITS 10

struct btQuantizedBvhNode
{
        BT_DECLARE_ALIGNED_ALLOCATOR();

        //12 bytes
        unsigned short int      m_quantizedAabbMin[3];
        unsigned short int      m_quantizedAabbMax[3];
        //4 bytes
        int     m_escapeIndexOrTriangleIndex;

        bool isLeafNode() const
        {
                //skipindex is negative (internal node), triangleindex >=0 (leafnode)
                return (m_escapeIndexOrTriangleIndex >= 0);
        }
        int getEscapeIndex() const
        {
                btAssert(!isLeafNode());
                return -m_escapeIndexOrTriangleIndex;
        }
        int     getTriangleIndex() const
        {
                btAssert(isLeafNode());
                // Get only the lower bits where the triangle index is stored
                return (m_escapeIndexOrTriangleIndex&~((~0)<<(31-MAX_NUM_PARTS_IN_BITS)));
        }
        int     getPartId() const
        {
                btAssert(isLeafNode());
                // Get only the highest bits where the part index is stored
                return (m_escapeIndexOrTriangleIndex>>(31-MAX_NUM_PARTS_IN_BITS));
        }
}
;

struct btOptimizedBvhNode
{
        BT_DECLARE_ALIGNED_ALLOCATOR();

        //32 bytes
        btVector3       m_aabbMinOrg;
        btVector3       m_aabbMaxOrg;

        //4
        int     m_escapeIndex;

        //8
        //for child nodes
        int     m_subPart;
        int     m_triangleIndex;
        int     m_padding[5];//bad, due to alignment


};


class btBvhSubtreeInfo
{
public:
        BT_DECLARE_ALIGNED_ALLOCATOR();

        //12 bytes
        unsigned short int      m_quantizedAabbMin[3];
        unsigned short int      m_quantizedAabbMax[3];
        //4 bytes, points to the root of the subtree
        int                     m_rootNodeIndex;
        //4 bytes
        int                     m_subtreeSize;
        int                     m_padding[3];

        btBvhSubtreeInfo()
        {
                //memset(&m_padding[0], 0, sizeof(m_padding));
        }


        void    setAabbFromQuantizeNode(const btQuantizedBvhNode& quantizedNode)
        {
                m_quantizedAabbMin[0] = quantizedNode.m_quantizedAabbMin[0];
                m_quantizedAabbMin[1] = quantizedNode.m_quantizedAabbMin[1];
                m_quantizedAabbMin[2] = quantizedNode.m_quantizedAabbMin[2];
                m_quantizedAabbMax[0] = quantizedNode.m_quantizedAabbMax[0];
                m_quantizedAabbMax[1] = quantizedNode.m_quantizedAabbMax[1];
                m_quantizedAabbMax[2] = quantizedNode.m_quantizedAabbMax[2];
        }
}
;


class btNodeOverlapCallback
{
public:
        virtual ~btNodeOverlapCallback() {};

        virtual void processNode(int subPart, int triangleIndex) = 0;
};

#include "LinearMath/btAlignedAllocator.h"
#include "LinearMath/btAlignedObjectArray.h"



typedef btAlignedObjectArray<btOptimizedBvhNode>        NodeArray;
typedef btAlignedObjectArray<btQuantizedBvhNode>        QuantizedNodeArray;
typedef btAlignedObjectArray<btBvhSubtreeInfo>          BvhSubtreeInfoArray;


class btQuantizedBvh
{
public:
        enum btTraversalMode
        {
                TRAVERSAL_STACKLESS = 0,
                TRAVERSAL_STACKLESS_CACHE_FRIENDLY,
                TRAVERSAL_RECURSIVE
        };

protected:


        btVector3                       m_bvhAabbMin;
        btVector3                       m_bvhAabbMax;
        btVector3                       m_bvhQuantization;

        int                                     m_bulletVersion;        //for serialization versioning. It could also be used to detect endianess.

        int                                     m_curNodeIndex;
        //quantization data
        bool                            m_useQuantization;



        NodeArray                       m_leafNodes;
        NodeArray                       m_contiguousNodes;
        QuantizedNodeArray      m_quantizedLeafNodes;
        QuantizedNodeArray      m_quantizedContiguousNodes;
        
        btTraversalMode m_traversalMode;
        BvhSubtreeInfoArray             m_SubtreeHeaders;

        //This is only used for serialization so we don't have to add serialization directly to btAlignedObjectArray
        mutable int m_subtreeHeaderCount;

        



        void    setInternalNodeAabbMin(int nodeIndex, const btVector3& aabbMin)
        {
                if (m_useQuantization)
                {
                        quantize(&m_quantizedContiguousNodes[nodeIndex].m_quantizedAabbMin[0] ,aabbMin,0);
                } else
                {
                        m_contiguousNodes[nodeIndex].m_aabbMinOrg = aabbMin;

                }
        }
        void    setInternalNodeAabbMax(int nodeIndex,const btVector3& aabbMax)
        {
                if (m_useQuantization)
                {
                        quantize(&m_quantizedContiguousNodes[nodeIndex].m_quantizedAabbMax[0],aabbMax,1);
                } else
                {
                        m_contiguousNodes[nodeIndex].m_aabbMaxOrg = aabbMax;
                }
        }

        btVector3 getAabbMin(int nodeIndex) const
        {
                if (m_useQuantization)
                {
                        return unQuantize(&m_quantizedLeafNodes[nodeIndex].m_quantizedAabbMin[0]);
                }
                //non-quantized
                return m_leafNodes[nodeIndex].m_aabbMinOrg;

        }
        btVector3 getAabbMax(int nodeIndex) const
        {
                if (m_useQuantization)
                {
                        return unQuantize(&m_quantizedLeafNodes[nodeIndex].m_quantizedAabbMax[0]);
                } 
                //non-quantized
                return m_leafNodes[nodeIndex].m_aabbMaxOrg;
                
        }

        
        void    setInternalNodeEscapeIndex(int nodeIndex, int escapeIndex)
        {
                if (m_useQuantization)
                {
                        m_quantizedContiguousNodes[nodeIndex].m_escapeIndexOrTriangleIndex = -escapeIndex;
                } 
                else
                {
                        m_contiguousNodes[nodeIndex].m_escapeIndex = escapeIndex;
                }

        }

        void mergeInternalNodeAabb(int nodeIndex,const btVector3& newAabbMin,const btVector3& newAabbMax) 
        {
                if (m_useQuantization)
                {
                        unsigned short int quantizedAabbMin[3];
                        unsigned short int quantizedAabbMax[3];
                        quantize(quantizedAabbMin,newAabbMin,0);
                        quantize(quantizedAabbMax,newAabbMax,1);
                        for (int i=0;i<3;i++)
                        {
                                if (m_quantizedContiguousNodes[nodeIndex].m_quantizedAabbMin[i] > quantizedAabbMin[i])
                                        m_quantizedContiguousNodes[nodeIndex].m_quantizedAabbMin[i] = quantizedAabbMin[i];

                                if (m_quantizedContiguousNodes[nodeIndex].m_quantizedAabbMax[i] < quantizedAabbMax[i])
                                        m_quantizedContiguousNodes[nodeIndex].m_quantizedAabbMax[i] = quantizedAabbMax[i];

                        }
                } else
                {
                        //non-quantized
                        m_contiguousNodes[nodeIndex].m_aabbMinOrg.setMin(newAabbMin);
                        m_contiguousNodes[nodeIndex].m_aabbMaxOrg.setMax(newAabbMax);           
                }
        }

        void    swapLeafNodes(int firstIndex,int secondIndex);

        void    assignInternalNodeFromLeafNode(int internalNode,int leafNodeIndex);

protected:

        

        void    buildTree       (int startIndex,int endIndex);

        int     calcSplittingAxis(int startIndex,int endIndex);

        int     sortAndCalcSplittingIndex(int startIndex,int endIndex,int splitAxis);
        
        void    walkStacklessTree(btNodeOverlapCallback* nodeCallback,const btVector3& aabbMin,const btVector3& aabbMax) const;

        void    walkStacklessQuantizedTreeAgainstRay(btNodeOverlapCallback* nodeCallback, const btVector3& raySource, const btVector3& rayTarget, const btVector3& aabbMin, const btVector3& aabbMax, int startNodeIndex,int endNodeIndex) const;
        void    walkStacklessQuantizedTree(btNodeOverlapCallback* nodeCallback,unsigned short int* quantizedQueryAabbMin,unsigned short int* quantizedQueryAabbMax,int startNodeIndex,int endNodeIndex) const;
        void    walkStacklessTreeAgainstRay(btNodeOverlapCallback* nodeCallback, const btVector3& raySource, const btVector3& rayTarget, const btVector3& aabbMin, const btVector3& aabbMax, int startNodeIndex,int endNodeIndex) const;

        void    walkStacklessQuantizedTreeCacheFriendly(btNodeOverlapCallback* nodeCallback,unsigned short int* quantizedQueryAabbMin,unsigned short int* quantizedQueryAabbMax) const;

        void    walkRecursiveQuantizedTreeAgainstQueryAabb(const btQuantizedBvhNode* currentNode,btNodeOverlapCallback* nodeCallback,unsigned short int* quantizedQueryAabbMin,unsigned short int* quantizedQueryAabbMax) const;

        void    walkRecursiveQuantizedTreeAgainstQuantizedTree(const btQuantizedBvhNode* treeNodeA,const btQuantizedBvhNode* treeNodeB,btNodeOverlapCallback* nodeCallback) const;
        



        void    updateSubtreeHeaders(int leftChildNodexIndex,int rightChildNodexIndex);

public:
        
        BT_DECLARE_ALIGNED_ALLOCATOR();

        btQuantizedBvh();

        virtual ~btQuantizedBvh();

        
        void    setQuantizationValues(const btVector3& bvhAabbMin,const btVector3& bvhAabbMax,btScalar quantizationMargin=btScalar(1.0));
        QuantizedNodeArray&     getLeafNodeArray() {                    return  m_quantizedLeafNodes;   }
        void    buildInternal();

        void    reportAabbOverlappingNodex(btNodeOverlapCallback* nodeCallback,const btVector3& aabbMin,const btVector3& aabbMax) const;
        void    reportRayOverlappingNodex (btNodeOverlapCallback* nodeCallback, const btVector3& raySource, const btVector3& rayTarget) const;
        void    reportBoxCastOverlappingNodex(btNodeOverlapCallback* nodeCallback, const btVector3& raySource, const btVector3& rayTarget, const btVector3& aabbMin,const btVector3& aabbMax) const;

                SIMD_FORCE_INLINE void quantize(unsigned short* out, const btVector3& point,int isMax) const
        {

                btAssert(m_useQuantization);

                btAssert(point.getX() <= m_bvhAabbMax.getX());
                btAssert(point.getY() <= m_bvhAabbMax.getY());
                btAssert(point.getZ() <= m_bvhAabbMax.getZ());

                btAssert(point.getX() >= m_bvhAabbMin.getX());
                btAssert(point.getY() >= m_bvhAabbMin.getY());
                btAssert(point.getZ() >= m_bvhAabbMin.getZ());

                btVector3 v = (point - m_bvhAabbMin) * m_bvhQuantization;
                if (isMax)
                {
                        out[0] = (unsigned short) (((unsigned short)(v.getX()+btScalar(1.)) | 1));
                        out[1] = (unsigned short) (((unsigned short)(v.getY()+btScalar(1.)) | 1));
                        out[2] = (unsigned short) (((unsigned short)(v.getZ()+btScalar(1.)) | 1));
                } else
                {
                        out[0] = (unsigned short) (((unsigned short)(v.getX()) & 0xfffe));
                        out[1] = (unsigned short) (((unsigned short)(v.getY()) & 0xfffe));
                        out[2] = (unsigned short) (((unsigned short)(v.getZ()) & 0xfffe));
                }


#ifdef DEBUG_CHECK_DEQUANTIZATION
                btVector3 newPoint = unQuantize(out);
                if (isMax)
                {
                        if (newPoint.getX() < point.getX())
                        {
                                printf("unconservative X, diffX = %f, oldX=%f,newX=%f\n",newPoint.getX()-point.getX(), newPoint.getX(),point.getX());
                        }
                        if (newPoint.getY() < point.getY())
                        {
                                printf("unconservative Y, diffY = %f, oldY=%f,newY=%f\n",newPoint.getY()-point.getY(), newPoint.getY(),point.getY());
                        }
                        if (newPoint.getZ() < point.getZ())
                        {

                                printf("unconservative Z, diffZ = %f, oldZ=%f,newZ=%f\n",newPoint.getZ()-point.getZ(), newPoint.getZ(),point.getZ());
                        }
                } else
                {
                        if (newPoint.getX() > point.getX())
                        {
                                printf("unconservative X, diffX = %f, oldX=%f,newX=%f\n",newPoint.getX()-point.getX(), newPoint.getX(),point.getX());
                        }
                        if (newPoint.getY() > point.getY())
                        {
                                printf("unconservative Y, diffY = %f, oldY=%f,newY=%f\n",newPoint.getY()-point.getY(), newPoint.getY(),point.getY());
                        }
                        if (newPoint.getZ() > point.getZ())
                        {
                                printf("unconservative Z, diffZ = %f, oldZ=%f,newZ=%f\n",newPoint.getZ()-point.getZ(), newPoint.getZ(),point.getZ());
                        }
                }
#endif //DEBUG_CHECK_DEQUANTIZATION

        }


        SIMD_FORCE_INLINE void quantizeWithClamp(unsigned short* out, const btVector3& point2,int isMax) const
        {

                btAssert(m_useQuantization);

                btVector3 clampedPoint(point2);
                clampedPoint.setMax(m_bvhAabbMin);
                clampedPoint.setMin(m_bvhAabbMax);

                quantize(out,clampedPoint,isMax);

        }
        
        SIMD_FORCE_INLINE btVector3     unQuantize(const unsigned short* vecIn) const
        {
                        btVector3       vecOut;
                        vecOut.setValue(
                        (btScalar)(vecIn[0]) / (m_bvhQuantization.getX()),
                        (btScalar)(vecIn[1]) / (m_bvhQuantization.getY()),
                        (btScalar)(vecIn[2]) / (m_bvhQuantization.getZ()));
                        vecOut += m_bvhAabbMin;
                        return vecOut;
        }

        void    setTraversalMode(btTraversalMode        traversalMode)
        {
                m_traversalMode = traversalMode;
        }


        SIMD_FORCE_INLINE QuantizedNodeArray&   getQuantizedNodeArray()
        {       
                return  m_quantizedContiguousNodes;
        }


        SIMD_FORCE_INLINE BvhSubtreeInfoArray&  getSubtreeInfoArray()
        {
                return m_SubtreeHeaders;
        }


        unsigned calculateSerializeBufferSize() const;

        virtual bool serialize(void *o_alignedDataBuffer, unsigned i_dataBufferSize, bool i_swapEndian) const;

        static btQuantizedBvh *deSerializeInPlace(void *i_alignedDataBuffer, unsigned int i_dataBufferSize, bool i_swapEndian);

        static unsigned int getAlignmentSerializationPadding();

        SIMD_FORCE_INLINE bool isQuantized()
        {
                return m_useQuantization;
        }

private:
        // Special "copy" constructor that allows for in-place deserialization
        // Prevents btVector3's default constructor from being called, but doesn't inialize much else
        // ownsMemory should most likely be false if deserializing, and if you are not, don't call this (it also changes the function signature, which we need)
        btQuantizedBvh(btQuantizedBvh &other, bool ownsMemory);

}
;


#endif //QUANTIZED_BVH_H