btInternalEdgeUtility.cpp

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#include "btInternalEdgeUtility.h"

#include "BulletCollision/CollisionShapes/btBvhTriangleMeshShape.h"
#include "BulletCollision/CollisionShapes/btScaledBvhTriangleMeshShape.h"
#include "BulletCollision/CollisionShapes/btTriangleShape.h"
#include "BulletCollision/CollisionDispatch/btCollisionObject.h"
#include "BulletCollision/NarrowPhaseCollision/btManifoldPoint.h"
#include "LinearMath/btIDebugDraw.h"
#include "BulletCollision/CollisionDispatch/btCollisionObjectWrapper.h"

//#define DEBUG_INTERNAL_EDGE

#ifdef DEBUG_INTERNAL_EDGE
#include <stdio.h>
#endif //DEBUG_INTERNAL_EDGE


#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
static btIDebugDraw* gDebugDrawer = 0;

void    btSetDebugDrawer(btIDebugDraw* debugDrawer)
{
        gDebugDrawer = debugDrawer;
}

static void    btDebugDrawLine(const btVector3& from,const btVector3& to, const btVector3& color)
{
        if (gDebugDrawer)
                gDebugDrawer->drawLine(from,to,color);
}
#endif //BT_INTERNAL_EDGE_DEBUG_DRAW


static int      btGetHash(int partId, int triangleIndex)
{
        int hash = (partId<<(31-MAX_NUM_PARTS_IN_BITS)) | triangleIndex;
        return hash;
}



static btScalar btGetAngle(const btVector3& edgeA, const btVector3& normalA,const btVector3& normalB)
{
        const btVector3 refAxis0  = edgeA;
        const btVector3 refAxis1  = normalA;
        const btVector3 swingAxis = normalB;
        btScalar angle = btAtan2(swingAxis.dot(refAxis0), swingAxis.dot(refAxis1));
        return  angle;
}


struct btConnectivityProcessor : public btTriangleCallback
{
        int                             m_partIdA;
        int                             m_triangleIndexA;
        btVector3*              m_triangleVerticesA;
        btTriangleInfoMap*      m_triangleInfoMap;


        virtual void processTriangle(btVector3* triangle, int partId, int triangleIndex)
        {
                //skip self-collisions
                if ((m_partIdA == partId) && (m_triangleIndexA == triangleIndex))
                        return;

                //skip duplicates (disabled for now)
                //if ((m_partIdA <= partId) && (m_triangleIndexA <= triangleIndex))
                //      return;

                //search for shared vertices and edges
                int numshared = 0;
                int sharedVertsA[3]={-1,-1,-1};
                int sharedVertsB[3]={-1,-1,-1};

                btScalar crossBSqr = ((triangle[1]-triangle[0]).cross(triangle[2]-triangle[0])).length2();
                if (crossBSqr < m_triangleInfoMap->m_equalVertexThreshold)
                        return;


                btScalar crossASqr = ((m_triangleVerticesA[1]-m_triangleVerticesA[0]).cross(m_triangleVerticesA[2]-m_triangleVerticesA[0])).length2();
                if (crossASqr< m_triangleInfoMap->m_equalVertexThreshold)
                        return;

#if 0
                printf("triangle A[0]   =       (%f,%f,%f)\ntriangle A[1]       =       (%f,%f,%f)\ntriangle A[2]       =       (%f,%f,%f)\n",
                        m_triangleVerticesA[0].getX(),m_triangleVerticesA[0].getY(),m_triangleVerticesA[0].getZ(),
                        m_triangleVerticesA[1].getX(),m_triangleVerticesA[1].getY(),m_triangleVerticesA[1].getZ(),
                        m_triangleVerticesA[2].getX(),m_triangleVerticesA[2].getY(),m_triangleVerticesA[2].getZ());

                printf("partId=%d, triangleIndex=%d\n",partId,triangleIndex);
                printf("triangle B[0]   =       (%f,%f,%f)\ntriangle B[1]       =       (%f,%f,%f)\ntriangle B[2]       =       (%f,%f,%f)\n",
                        triangle[0].getX(),triangle[0].getY(),triangle[0].getZ(),
                        triangle[1].getX(),triangle[1].getY(),triangle[1].getZ(),
                        triangle[2].getX(),triangle[2].getY(),triangle[2].getZ());
#endif

                for (int i=0;i<3;i++)
                {
                        for (int j=0;j<3;j++)
                        {
                                if ( (m_triangleVerticesA[i]-triangle[j]).length2() < m_triangleInfoMap->m_equalVertexThreshold)
                                {
                                        sharedVertsA[numshared] = i;
                                        sharedVertsB[numshared] = j;
                                        numshared++;
                                        if(numshared >= 3)
                                                return;
                                }
                        }
                        if(numshared >= 3)
                                return;
                }
                switch (numshared)
                {
                case 0:
                        {
                                break;
                        }
                case 1:
                        {
                                //shared vertex
                                break;
                        }
                case 2:
                        {
                                //shared edge
                                //we need to make sure the edge is in the order V2V0 and not V0V2 so that the signs are correct
                                if (sharedVertsA[0] == 0 && sharedVertsA[1] == 2)
                                {
                                        sharedVertsA[0] = 2;
                                        sharedVertsA[1] = 0;
                                        int tmp = sharedVertsB[1];
                                        sharedVertsB[1] = sharedVertsB[0];
                                        sharedVertsB[0] = tmp;
                                }

                                int hash = btGetHash(m_partIdA,m_triangleIndexA);

                                btTriangleInfo* info = m_triangleInfoMap->find(hash);
                                if (!info)
                                {
                                        btTriangleInfo tmp;
                                        m_triangleInfoMap->insert(hash,tmp);
                                        info = m_triangleInfoMap->find(hash);
                                }

                                int sumvertsA = sharedVertsA[0]+sharedVertsA[1];
                                int otherIndexA = 3-sumvertsA;

                                
                                btVector3 edge(m_triangleVerticesA[sharedVertsA[1]]-m_triangleVerticesA[sharedVertsA[0]]);

                                btTriangleShape tA(m_triangleVerticesA[0],m_triangleVerticesA[1],m_triangleVerticesA[2]);
                                int otherIndexB = 3-(sharedVertsB[0]+sharedVertsB[1]);

                                btTriangleShape tB(triangle[sharedVertsB[1]],triangle[sharedVertsB[0]],triangle[otherIndexB]);
                                //btTriangleShape tB(triangle[0],triangle[1],triangle[2]);

                                btVector3 normalA;
                                btVector3 normalB;
                                tA.calcNormal(normalA);
                                tB.calcNormal(normalB);
                                edge.normalize();
                                btVector3 edgeCrossA = edge.cross(normalA).normalize();

                                {
                                        btVector3 tmp = m_triangleVerticesA[otherIndexA]-m_triangleVerticesA[sharedVertsA[0]];
                                        if (edgeCrossA.dot(tmp) < 0)
                                        {
                                                edgeCrossA*=-1;
                                        }
                                }

                                btVector3 edgeCrossB = edge.cross(normalB).normalize();

                                {
                                        btVector3 tmp = triangle[otherIndexB]-triangle[sharedVertsB[0]];
                                        if (edgeCrossB.dot(tmp) < 0)
                                        {
                                                edgeCrossB*=-1;
                                        }
                                }

                                btScalar        angle2 = 0;
                                btScalar        ang4 = 0.f;


                                btVector3 calculatedEdge = edgeCrossA.cross(edgeCrossB);
                                btScalar len2 = calculatedEdge.length2();

                                btScalar correctedAngle(0);
                                btVector3 calculatedNormalB = normalA;
                                bool isConvex = false;

                                if (len2<m_triangleInfoMap->m_planarEpsilon)
                                {
                                        angle2 = 0.f;
                                        ang4 = 0.f;
                                } else
                                {

                                        calculatedEdge.normalize();
                                        btVector3 calculatedNormalA = calculatedEdge.cross(edgeCrossA);
                                        calculatedNormalA.normalize();
                                        angle2 = btGetAngle(calculatedNormalA,edgeCrossA,edgeCrossB);
                                        ang4 = SIMD_PI-angle2;
                                        btScalar dotA = normalA.dot(edgeCrossB);
                                        isConvex = (dotA<0.);

                                        correctedAngle = isConvex ? ang4 : -ang4;
                                        btQuaternion orn2(calculatedEdge,-correctedAngle);
                                        calculatedNormalB = btMatrix3x3(orn2)*normalA;


                                }

                                

                                
                                                        
                                //alternatively use 
                                //btVector3 calculatedNormalB2 = quatRotate(orn,normalA);


                                switch (sumvertsA)
                                {
                                case 1:
                                        {
                                                btVector3 edge = m_triangleVerticesA[0]-m_triangleVerticesA[1];
                                                btQuaternion orn(edge,-correctedAngle);
                                                btVector3 computedNormalB = quatRotate(orn,normalA);
                                                btScalar bla = computedNormalB.dot(normalB);
                                                if (bla<0)
                                                {
                                                        computedNormalB*=-1;
                                                        info->m_flags |= TRI_INFO_V0V1_SWAP_NORMALB;
                                                }
#ifdef DEBUG_INTERNAL_EDGE
                                                if ((computedNormalB-normalB).length()>0.0001)
                                                {
                                                        printf("warning: normals not identical\n");
                                                }
#endif//DEBUG_INTERNAL_EDGE

                                                info->m_edgeV0V1Angle = -correctedAngle;

                                                if (isConvex)
                                                        info->m_flags |= TRI_INFO_V0V1_CONVEX;
                                                break;
                                        }
                                case 2:
                                        {
                                                btVector3 edge = m_triangleVerticesA[2]-m_triangleVerticesA[0];
                                                btQuaternion orn(edge,-correctedAngle);
                                                btVector3 computedNormalB = quatRotate(orn,normalA);
                                                if (computedNormalB.dot(normalB)<0)
                                                {
                                                        computedNormalB*=-1;
                                                        info->m_flags |= TRI_INFO_V2V0_SWAP_NORMALB;
                                                }

#ifdef DEBUG_INTERNAL_EDGE
                                                if ((computedNormalB-normalB).length()>0.0001)
                                                {
                                                        printf("warning: normals not identical\n");
                                                }
#endif //DEBUG_INTERNAL_EDGE
                                                info->m_edgeV2V0Angle = -correctedAngle;
                                                if (isConvex)
                                                        info->m_flags |= TRI_INFO_V2V0_CONVEX;
                                                break;  
                                        }
                                case 3:
                                        {
                                                btVector3 edge = m_triangleVerticesA[1]-m_triangleVerticesA[2];
                                                btQuaternion orn(edge,-correctedAngle);
                                                btVector3 computedNormalB = quatRotate(orn,normalA);
                                                if (computedNormalB.dot(normalB)<0)
                                                {
                                                        info->m_flags |= TRI_INFO_V1V2_SWAP_NORMALB;
                                                        computedNormalB*=-1;
                                                }
#ifdef DEBUG_INTERNAL_EDGE
                                                if ((computedNormalB-normalB).length()>0.0001)
                                                {
                                                        printf("warning: normals not identical\n");
                                                }
#endif //DEBUG_INTERNAL_EDGE
                                                info->m_edgeV1V2Angle = -correctedAngle;

                                                if (isConvex)
                                                        info->m_flags |= TRI_INFO_V1V2_CONVEX;
                                                break;
                                        }
                                }

                                break;
                        }
                default:
                        {
                                //                              printf("warning: duplicate triangle\n");
                        }

                }
        }
};

void btGenerateInternalEdgeInfo (btBvhTriangleMeshShape*trimeshShape, btTriangleInfoMap* triangleInfoMap)
{
        //the user pointer shouldn't already be used for other purposes, we intend to store connectivity info there!
        if (trimeshShape->getTriangleInfoMap())
                return;

        trimeshShape->setTriangleInfoMap(triangleInfoMap);

        btStridingMeshInterface* meshInterface = trimeshShape->getMeshInterface();
        const btVector3& meshScaling = meshInterface->getScaling();

        for (int partId = 0; partId< meshInterface->getNumSubParts();partId++)
        {
                const unsigned char *vertexbase = 0;
                int numverts = 0;
                PHY_ScalarType type = PHY_INTEGER;
                int stride = 0;
                const unsigned char *indexbase = 0;
                int indexstride = 0;
                int numfaces = 0;
                PHY_ScalarType indicestype = PHY_INTEGER;
                //PHY_ScalarType indexType=0;

                btVector3 triangleVerts[3];
                meshInterface->getLockedReadOnlyVertexIndexBase(&vertexbase,numverts,   type,stride,&indexbase,indexstride,numfaces,indicestype,partId);
                btVector3 aabbMin,aabbMax;

                for (int triangleIndex = 0 ; triangleIndex < numfaces;triangleIndex++)
                {
                        unsigned int* gfxbase = (unsigned int*)(indexbase+triangleIndex*indexstride);

                        for (int j=2;j>=0;j--)
                        {

                                int graphicsindex = indicestype==PHY_SHORT?((unsigned short*)gfxbase)[j]:gfxbase[j];
                                if (type == PHY_FLOAT)
                                {
                                        float* graphicsbase = (float*)(vertexbase+graphicsindex*stride);
                                        triangleVerts[j] = btVector3(
                                                graphicsbase[0]*meshScaling.getX(),
                                                graphicsbase[1]*meshScaling.getY(),
                                                graphicsbase[2]*meshScaling.getZ());
                                }
                                else
                                {
                                        double* graphicsbase = (double*)(vertexbase+graphicsindex*stride);
                                        triangleVerts[j] = btVector3( btScalar(graphicsbase[0]*meshScaling.getX()), btScalar(graphicsbase[1]*meshScaling.getY()), btScalar(graphicsbase[2]*meshScaling.getZ()));
                                }
                        }
                        aabbMin.setValue(btScalar(BT_LARGE_FLOAT),btScalar(BT_LARGE_FLOAT),btScalar(BT_LARGE_FLOAT));
                        aabbMax.setValue(btScalar(-BT_LARGE_FLOAT),btScalar(-BT_LARGE_FLOAT),btScalar(-BT_LARGE_FLOAT)); 
                        aabbMin.setMin(triangleVerts[0]);
                        aabbMax.setMax(triangleVerts[0]);
                        aabbMin.setMin(triangleVerts[1]);
                        aabbMax.setMax(triangleVerts[1]);
                        aabbMin.setMin(triangleVerts[2]);
                        aabbMax.setMax(triangleVerts[2]);

                        btConnectivityProcessor connectivityProcessor;
                        connectivityProcessor.m_partIdA = partId;
                        connectivityProcessor.m_triangleIndexA = triangleIndex;
                        connectivityProcessor.m_triangleVerticesA = &triangleVerts[0];
                        connectivityProcessor.m_triangleInfoMap  = triangleInfoMap;

                        trimeshShape->processAllTriangles(&connectivityProcessor,aabbMin,aabbMax);
                }

        }

}




// Given a point and a line segment (defined by two points), compute the closest point
// in the line.  Cap the point at the endpoints of the line segment.
void btNearestPointInLineSegment(const btVector3 &point, const btVector3& line0, const btVector3& line1, btVector3& nearestPoint)
{
        btVector3 lineDelta     = line1 - line0;

        // Handle degenerate lines
        if ( lineDelta.fuzzyZero())
        {
                nearestPoint = line0;
        }
        else
        {
                btScalar delta = (point-line0).dot(lineDelta) / (lineDelta).dot(lineDelta);

                // Clamp the point to conform to the segment's endpoints
                if ( delta < 0 )
                        delta = 0;
                else if ( delta > 1 )
                        delta = 1;

                nearestPoint = line0 + lineDelta*delta;
        }
}




bool    btClampNormal(const btVector3& edge,const btVector3& tri_normal_org,const btVector3& localContactNormalOnB, btScalar correctedEdgeAngle, btVector3 & clampedLocalNormal)
{
        btVector3 tri_normal = tri_normal_org;
        //we only have a local triangle normal, not a local contact normal -> only normal in world space...
        //either compute the current angle all in local space, or all in world space

        btVector3 edgeCross = edge.cross(tri_normal).normalize();
        btScalar curAngle = btGetAngle(edgeCross,tri_normal,localContactNormalOnB);

        if (correctedEdgeAngle<0)
        {
                if (curAngle < correctedEdgeAngle)
                {
                        btScalar diffAngle = correctedEdgeAngle-curAngle;
                        btQuaternion rotation(edge,diffAngle );
                        clampedLocalNormal = btMatrix3x3(rotation)*localContactNormalOnB;
                        return true;
                }
        }

        if (correctedEdgeAngle>=0)
        {
                if (curAngle > correctedEdgeAngle)
                {
                        btScalar diffAngle = correctedEdgeAngle-curAngle;
                        btQuaternion rotation(edge,diffAngle );
                        clampedLocalNormal = btMatrix3x3(rotation)*localContactNormalOnB;
                        return true;
                }
        }
        return false;
}



void btAdjustInternalEdgeContacts(btManifoldPoint& cp, const btCollisionObjectWrapper* colObj0Wrap,const btCollisionObjectWrapper* colObj1Wrap, int partId0, int index0, int normalAdjustFlags)
{
        //btAssert(colObj0->getCollisionShape()->getShapeType() == TRIANGLE_SHAPE_PROXYTYPE);
        if (colObj0Wrap->getCollisionShape()->getShapeType() != TRIANGLE_SHAPE_PROXYTYPE)
                return;

        btBvhTriangleMeshShape* trimesh = 0;
        
        if( colObj0Wrap->getCollisionObject()->getCollisionShape()->getShapeType() == SCALED_TRIANGLE_MESH_SHAPE_PROXYTYPE )
           trimesh = ((btScaledBvhTriangleMeshShape*)colObj0Wrap->getCollisionObject()->getCollisionShape())->getChildShape();
   else    
           trimesh = (btBvhTriangleMeshShape*)colObj0Wrap->getCollisionObject()->getCollisionShape();
           
        btTriangleInfoMap* triangleInfoMapPtr = (btTriangleInfoMap*) trimesh->getTriangleInfoMap();
        if (!triangleInfoMapPtr)
                return;

        int hash = btGetHash(partId0,index0);


        btTriangleInfo* info = triangleInfoMapPtr->find(hash);
        if (!info)
                return;

        btScalar frontFacing = (normalAdjustFlags & BT_TRIANGLE_CONVEX_BACKFACE_MODE)==0? 1.f : -1.f;
        
        const btTriangleShape* tri_shape = static_cast<const btTriangleShape*>(colObj0Wrap->getCollisionShape());
        btVector3 v0,v1,v2;
        tri_shape->getVertex(0,v0);
        tri_shape->getVertex(1,v1);
        tri_shape->getVertex(2,v2);

        //btVector3 center = (v0+v1+v2)*btScalar(1./3.);

        btVector3 red(1,0,0), green(0,1,0),blue(0,0,1),white(1,1,1),black(0,0,0);
        btVector3 tri_normal;
        tri_shape->calcNormal(tri_normal);

        //btScalar dot = tri_normal.dot(cp.m_normalWorldOnB);
        btVector3 nearest;
        btNearestPointInLineSegment(cp.m_localPointB,v0,v1,nearest);

        btVector3 contact = cp.m_localPointB;
#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
        const btTransform& tr = colObj0->getWorldTransform();
        btDebugDrawLine(tr*nearest,tr*cp.m_localPointB,red);
#endif //BT_INTERNAL_EDGE_DEBUG_DRAW



        bool isNearEdge = false;

        int numConcaveEdgeHits = 0;
        int numConvexEdgeHits = 0;

        btVector3 localContactNormalOnB = colObj0Wrap->getWorldTransform().getBasis().transpose() * cp.m_normalWorldOnB;
        localContactNormalOnB.normalize();//is this necessary?
        
        // Get closest edge
        int      bestedge=-1;
        btScalar    disttobestedge=BT_LARGE_FLOAT;
        //
        // Edge 0 -> 1
        if (btFabs(info->m_edgeV0V1Angle)< triangleInfoMapPtr->m_maxEdgeAngleThreshold)
        {       
           btVector3 nearest;
           btNearestPointInLineSegment( cp.m_localPointB, v0, v1, nearest );
           btScalar     len=(contact-nearest).length();
           //
           if( len < disttobestedge )
           {
              bestedge=0;
              disttobestedge=len;
      }       
   }       
        // Edge 1 -> 2
        if (btFabs(info->m_edgeV1V2Angle)< triangleInfoMapPtr->m_maxEdgeAngleThreshold)
        {       
           btVector3 nearest;
           btNearestPointInLineSegment( cp.m_localPointB, v1, v2, nearest );
           btScalar     len=(contact-nearest).length();
           //
           if( len < disttobestedge )
           {
              bestedge=1;
              disttobestedge=len;
      }       
   }       
        // Edge 2 -> 0
        if (btFabs(info->m_edgeV2V0Angle)< triangleInfoMapPtr->m_maxEdgeAngleThreshold)
        {       
           btVector3 nearest;
           btNearestPointInLineSegment( cp.m_localPointB, v2, v0, nearest );
           btScalar     len=(contact-nearest).length();
           //
           if( len < disttobestedge )
           {
              bestedge=2;
              disttobestedge=len;
      }       
   }            
        
#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
   btVector3 upfix=tri_normal * btVector3(0.1f,0.1f,0.1f);
   btDebugDrawLine(tr * v0 + upfix, tr * v1 + upfix, red );
#endif   
        if (btFabs(info->m_edgeV0V1Angle)< triangleInfoMapPtr->m_maxEdgeAngleThreshold)
        {
#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
                btDebugDrawLine(tr*contact,tr*(contact+cp.m_normalWorldOnB*10),black);
#endif
                btScalar len = (contact-nearest).length();
                if(len<triangleInfoMapPtr->m_edgeDistanceThreshold)
                if( bestedge==0 )
                {
                        btVector3 edge(v0-v1);
                        isNearEdge = true;

                        if (info->m_edgeV0V1Angle==btScalar(0))
                        {
                                numConcaveEdgeHits++;
                        } else
                        {

                                bool isEdgeConvex = (info->m_flags & TRI_INFO_V0V1_CONVEX);
                                btScalar swapFactor = isEdgeConvex ? btScalar(1) : btScalar(-1);
        #ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
                                btDebugDrawLine(tr*nearest,tr*(nearest+swapFactor*tri_normal*10),white);
        #endif //BT_INTERNAL_EDGE_DEBUG_DRAW

                                btVector3 nA = swapFactor * tri_normal;

                                btQuaternion orn(edge,info->m_edgeV0V1Angle);
                                btVector3 computedNormalB = quatRotate(orn,tri_normal);
                                if (info->m_flags & TRI_INFO_V0V1_SWAP_NORMALB)
                                        computedNormalB*=-1;
                                btVector3 nB = swapFactor*computedNormalB;

                                btScalar        NdotA = localContactNormalOnB.dot(nA);
                                btScalar        NdotB = localContactNormalOnB.dot(nB);
                                bool backFacingNormal = (NdotA< triangleInfoMapPtr->m_convexEpsilon) && (NdotB<triangleInfoMapPtr->m_convexEpsilon);

#ifdef DEBUG_INTERNAL_EDGE
                                {
                                        
                                        btDebugDrawLine(cp.getPositionWorldOnB(),cp.getPositionWorldOnB()+tr.getBasis()*(nB*20),red);
                                }
#endif //DEBUG_INTERNAL_EDGE


                                if (backFacingNormal)
                                {
                                        numConcaveEdgeHits++;
                                }
                                else
                                {
                                        numConvexEdgeHits++;
                                        btVector3 clampedLocalNormal;
                                        bool isClamped = btClampNormal(edge,swapFactor*tri_normal,localContactNormalOnB, info->m_edgeV0V1Angle,clampedLocalNormal);
                                        if (isClamped)
                                        {
                                                if (((normalAdjustFlags & BT_TRIANGLE_CONVEX_DOUBLE_SIDED)!=0) || (clampedLocalNormal.dot(frontFacing*tri_normal)>0))
                                                {
                                                        btVector3 newNormal = colObj0Wrap->getWorldTransform().getBasis() * clampedLocalNormal;
                                                        //                                      cp.m_distance1 = cp.m_distance1 * newNormal.dot(cp.m_normalWorldOnB);
                                                        cp.m_normalWorldOnB = newNormal;
                                                        // Reproject collision point along normal. (what about cp.m_distance1?)
                                                        cp.m_positionWorldOnB = cp.m_positionWorldOnA - cp.m_normalWorldOnB * cp.m_distance1;
                                                        cp.m_localPointB = colObj0Wrap->getWorldTransform().invXform(cp.m_positionWorldOnB);
                                                        
                                                }
                                        }
                                }
                        }
                }
        }

        btNearestPointInLineSegment(contact,v1,v2,nearest);
#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
        btDebugDrawLine(tr*nearest,tr*cp.m_localPointB,green);
#endif //BT_INTERNAL_EDGE_DEBUG_DRAW

#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
   btDebugDrawLine(tr * v1 + upfix, tr * v2 + upfix , green );
#endif   

        if (btFabs(info->m_edgeV1V2Angle)< triangleInfoMapPtr->m_maxEdgeAngleThreshold)
        {
#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
                btDebugDrawLine(tr*contact,tr*(contact+cp.m_normalWorldOnB*10),black);
#endif //BT_INTERNAL_EDGE_DEBUG_DRAW



                btScalar len = (contact-nearest).length();
                if(len<triangleInfoMapPtr->m_edgeDistanceThreshold)
                if( bestedge==1 )
                {
                        isNearEdge = true;
#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
                        btDebugDrawLine(tr*nearest,tr*(nearest+tri_normal*10),white);
#endif //BT_INTERNAL_EDGE_DEBUG_DRAW

                        btVector3 edge(v1-v2);

                        isNearEdge = true;

                        if (info->m_edgeV1V2Angle == btScalar(0))
                        {
                                numConcaveEdgeHits++;
                        } else
                        {
                                bool isEdgeConvex = (info->m_flags & TRI_INFO_V1V2_CONVEX)!=0;
                                btScalar swapFactor = isEdgeConvex ? btScalar(1) : btScalar(-1);
        #ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
                                btDebugDrawLine(tr*nearest,tr*(nearest+swapFactor*tri_normal*10),white);
        #endif //BT_INTERNAL_EDGE_DEBUG_DRAW

                                btVector3 nA = swapFactor * tri_normal;
                                
                                btQuaternion orn(edge,info->m_edgeV1V2Angle);
                                btVector3 computedNormalB = quatRotate(orn,tri_normal);
                                if (info->m_flags & TRI_INFO_V1V2_SWAP_NORMALB)
                                        computedNormalB*=-1;
                                btVector3 nB = swapFactor*computedNormalB;

#ifdef DEBUG_INTERNAL_EDGE
                                {
                                        btDebugDrawLine(cp.getPositionWorldOnB(),cp.getPositionWorldOnB()+tr.getBasis()*(nB*20),red);
                                }
#endif //DEBUG_INTERNAL_EDGE


                                btScalar        NdotA = localContactNormalOnB.dot(nA);
                                btScalar        NdotB = localContactNormalOnB.dot(nB);
                                bool backFacingNormal = (NdotA< triangleInfoMapPtr->m_convexEpsilon) && (NdotB<triangleInfoMapPtr->m_convexEpsilon);

                                if (backFacingNormal)
                                {
                                        numConcaveEdgeHits++;
                                }
                                else
                                {
                                        numConvexEdgeHits++;
                                        btVector3 localContactNormalOnB = colObj0Wrap->getWorldTransform().getBasis().transpose() * cp.m_normalWorldOnB;
                                        btVector3 clampedLocalNormal;
                                        bool isClamped = btClampNormal(edge,swapFactor*tri_normal,localContactNormalOnB, info->m_edgeV1V2Angle,clampedLocalNormal);
                                        if (isClamped)
                                        {
                                                if (((normalAdjustFlags & BT_TRIANGLE_CONVEX_DOUBLE_SIDED)!=0) || (clampedLocalNormal.dot(frontFacing*tri_normal)>0))
                                                {
                                                        btVector3 newNormal = colObj0Wrap->getWorldTransform().getBasis() * clampedLocalNormal;
                                                        //                                      cp.m_distance1 = cp.m_distance1 * newNormal.dot(cp.m_normalWorldOnB);
                                                        cp.m_normalWorldOnB = newNormal;
                                                        // Reproject collision point along normal.
                                                        cp.m_positionWorldOnB = cp.m_positionWorldOnA - cp.m_normalWorldOnB * cp.m_distance1;
                                                        cp.m_localPointB = colObj0Wrap->getWorldTransform().invXform(cp.m_positionWorldOnB);
                                                }
                                        }
                                }
                        }
                }
        }

        btNearestPointInLineSegment(contact,v2,v0,nearest);
#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
        btDebugDrawLine(tr*nearest,tr*cp.m_localPointB,blue);
#endif //BT_INTERNAL_EDGE_DEBUG_DRAW
#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
   btDebugDrawLine(tr * v2 + upfix, tr * v0 + upfix , blue );
#endif   

        if (btFabs(info->m_edgeV2V0Angle)< triangleInfoMapPtr->m_maxEdgeAngleThreshold)
        {

#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
                btDebugDrawLine(tr*contact,tr*(contact+cp.m_normalWorldOnB*10),black);
#endif //BT_INTERNAL_EDGE_DEBUG_DRAW

                btScalar len = (contact-nearest).length();
                if(len<triangleInfoMapPtr->m_edgeDistanceThreshold)
                if( bestedge==2 )
                {
                        isNearEdge = true;
#ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
                        btDebugDrawLine(tr*nearest,tr*(nearest+tri_normal*10),white);
#endif //BT_INTERNAL_EDGE_DEBUG_DRAW

                        btVector3 edge(v2-v0);

                        if (info->m_edgeV2V0Angle==btScalar(0))
                        {
                                numConcaveEdgeHits++;
                        } else
                        {

                                bool isEdgeConvex = (info->m_flags & TRI_INFO_V2V0_CONVEX)!=0;
                                btScalar swapFactor = isEdgeConvex ? btScalar(1) : btScalar(-1);
        #ifdef BT_INTERNAL_EDGE_DEBUG_DRAW
                                btDebugDrawLine(tr*nearest,tr*(nearest+swapFactor*tri_normal*10),white);
        #endif //BT_INTERNAL_EDGE_DEBUG_DRAW

                                btVector3 nA = swapFactor * tri_normal;
                                btQuaternion orn(edge,info->m_edgeV2V0Angle);
                                btVector3 computedNormalB = quatRotate(orn,tri_normal);
                                if (info->m_flags & TRI_INFO_V2V0_SWAP_NORMALB)
                                        computedNormalB*=-1;
                                btVector3 nB = swapFactor*computedNormalB;

#ifdef DEBUG_INTERNAL_EDGE
                                {
                                        btDebugDrawLine(cp.getPositionWorldOnB(),cp.getPositionWorldOnB()+tr.getBasis()*(nB*20),red);
                                }
#endif //DEBUG_INTERNAL_EDGE

                                btScalar        NdotA = localContactNormalOnB.dot(nA);
                                btScalar        NdotB = localContactNormalOnB.dot(nB);
                                bool backFacingNormal = (NdotA< triangleInfoMapPtr->m_convexEpsilon) && (NdotB<triangleInfoMapPtr->m_convexEpsilon);

                                if (backFacingNormal)
                                {
                                        numConcaveEdgeHits++;
                                }
                                else
                                {
                                        numConvexEdgeHits++;
                                        //                              printf("hitting convex edge\n");


                                        btVector3 localContactNormalOnB = colObj0Wrap->getWorldTransform().getBasis().transpose() * cp.m_normalWorldOnB;
                                        btVector3 clampedLocalNormal;
                                        bool isClamped = btClampNormal(edge,swapFactor*tri_normal,localContactNormalOnB,info->m_edgeV2V0Angle,clampedLocalNormal);
                                        if (isClamped)
                                        {
                                                if (((normalAdjustFlags & BT_TRIANGLE_CONVEX_DOUBLE_SIDED)!=0) || (clampedLocalNormal.dot(frontFacing*tri_normal)>0))
                                                {
                                                        btVector3 newNormal = colObj0Wrap->getWorldTransform().getBasis() * clampedLocalNormal;
                                                        //                                      cp.m_distance1 = cp.m_distance1 * newNormal.dot(cp.m_normalWorldOnB);
                                                        cp.m_normalWorldOnB = newNormal;
                                                        // Reproject collision point along normal.
                                                        cp.m_positionWorldOnB = cp.m_positionWorldOnA - cp.m_normalWorldOnB * cp.m_distance1;
                                                        cp.m_localPointB = colObj0Wrap->getWorldTransform().invXform(cp.m_positionWorldOnB);
                                                }
                                        }
                                } 
                        }
                        

                }
        }

#ifdef DEBUG_INTERNAL_EDGE
        {
                btVector3 color(0,1,1);
                btDebugDrawLine(cp.getPositionWorldOnB(),cp.getPositionWorldOnB()+cp.m_normalWorldOnB*10,color);
        }
#endif //DEBUG_INTERNAL_EDGE

        if (isNearEdge)
        {

                if (numConcaveEdgeHits>0)
                {
                        if ((normalAdjustFlags & BT_TRIANGLE_CONCAVE_DOUBLE_SIDED)!=0)
                        {
                                //fix tri_normal so it pointing the same direction as the current local contact normal
                                if (tri_normal.dot(localContactNormalOnB) < 0)
                                {
                                        tri_normal *= -1;
                                }
                                cp.m_normalWorldOnB = colObj0Wrap->getWorldTransform().getBasis()*tri_normal;
                        } else
                        {
                                btVector3 newNormal = tri_normal *frontFacing;
                                //if the tri_normal is pointing opposite direction as the current local contact normal, skip it
                                btScalar d = newNormal.dot(localContactNormalOnB) ;
                                if (d< 0)
                                {
                                        return;
                                }
                                //modify the normal to be the triangle normal (or backfacing normal)
                                cp.m_normalWorldOnB = colObj0Wrap->getWorldTransform().getBasis() *newNormal;
                        }
                                                
                        // Reproject collision point along normal.
                        cp.m_positionWorldOnB = cp.m_positionWorldOnA - cp.m_normalWorldOnB * cp.m_distance1;
                        cp.m_localPointB = colObj0Wrap->getWorldTransform().invXform(cp.m_positionWorldOnB);
                }
        }
}