void btMultiBodyConstraintSolver::setupMultiBodyContactConstraint(btMultiBodySolverConstraint& solverConstraint, 
																 const btVector3& contactNormal,
																 btManifoldPoint& cp, const btContactSolverInfo& infoGlobal,
																 btScalar& relaxation,
																 bool isFriction, btScalar desiredVelocity, btScalar cfmSlip)
{
			
	BT_PROFILE("setupMultiBodyContactConstraint");
	btVector3 rel_pos1;
	btVector3 rel_pos2;

	btMultiBody* multiBodyA = solverConstraint.m_multiBodyA;
	btMultiBody* multiBodyB = solverConstraint.m_multiBodyB;

	const btVector3& pos1 = cp.getPositionWorldOnA();
	const btVector3& pos2 = cp.getPositionWorldOnB();

	btSolverBody* bodyA = multiBodyA ? 0 : &m_tmpSolverBodyPool[solverConstraint.m_solverBodyIdA];
	btSolverBody* bodyB = multiBodyB ? 0 : &m_tmpSolverBodyPool[solverConstraint.m_solverBodyIdB];

	btRigidBody* rb0 = multiBodyA ? 0 : bodyA->m_originalBody;
	btRigidBody* rb1 = multiBodyB ? 0 : bodyB->m_originalBody;

	if (bodyA)
		rel_pos1 = pos1 - bodyA->getWorldTransform().getOrigin(); 
	if (bodyB)
		rel_pos2 = pos2 - bodyB->getWorldTransform().getOrigin();

	relaxation = 1.f;

	


	if (multiBodyA)
	{
		if (solverConstraint.m_linkA<0)
		{
			rel_pos1 = pos1 - multiBodyA->getBasePos();
		} else
		{
			rel_pos1 = pos1 - multiBodyA->getLink(solverConstraint.m_linkA).m_cachedWorldTransform.getOrigin();
		}
		const int ndofA  = (multiBodyA->isMultiDof() ? multiBodyA->getNumDofs() : multiBodyA->getNumLinks()) + 6;

		solverConstraint.m_deltaVelAindex = multiBodyA->getCompanionId();

		if (solverConstraint.m_deltaVelAindex <0)
		{
			solverConstraint.m_deltaVelAindex = m_data.m_deltaVelocities.size();
			multiBodyA->setCompanionId(solverConstraint.m_deltaVelAindex);
			m_data.m_deltaVelocities.resize(m_data.m_deltaVelocities.size()+ndofA);
		} else
		{
			btAssert(m_data.m_deltaVelocities.size() >= solverConstraint.m_deltaVelAindex+ndofA);
		}

		solverConstraint.m_jacAindex = m_data.m_jacobians.size();
		m_data.m_jacobians.resize(m_data.m_jacobians.size()+ndofA);
		m_data.m_deltaVelocitiesUnitImpulse.resize(m_data.m_deltaVelocitiesUnitImpulse.size()+ndofA);
		btAssert(m_data.m_jacobians.size() == m_data.m_deltaVelocitiesUnitImpulse.size());

		btScalar* jac1=&m_data.m_jacobians[solverConstraint.m_jacAindex];
		if(multiBodyA->isMultiDof())
			multiBodyA->fillContactJacobianMultiDof(solverConstraint.m_linkA, cp.getPositionWorldOnA(), contactNormal, jac1, m_data.scratch_r, m_data.scratch_v, m_data.scratch_m);
		else
			multiBodyA->fillContactJacobian(solverConstraint.m_linkA, cp.getPositionWorldOnA(), contactNormal, jac1, m_data.scratch_r, m_data.scratch_v, m_data.scratch_m);
		btScalar* delta = &m_data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacAindex];
		if(multiBodyA->isMultiDof())
			multiBodyA->calcAccelerationDeltasMultiDof(&m_data.m_jacobians[solverConstraint.m_jacAindex],delta,m_data.scratch_r, m_data.scratch_v);
		else
			multiBodyA->calcAccelerationDeltas(&m_data.m_jacobians[solverConstraint.m_jacAindex],delta,m_data.scratch_r, m_data.scratch_v);

		btVector3 torqueAxis0 = rel_pos1.cross(contactNormal);
		solverConstraint.m_relpos1CrossNormal = torqueAxis0;
		solverConstraint.m_contactNormal1 = contactNormal;
	} else
	{
		btVector3 torqueAxis0 = rel_pos1.cross(contactNormal);
		solverConstraint.m_relpos1CrossNormal = torqueAxis0;
		solverConstraint.m_contactNormal1 = contactNormal;
		solverConstraint.m_angularComponentA = rb0 ? rb0->getInvInertiaTensorWorld()*torqueAxis0*rb0->getAngularFactor() : btVector3(0,0,0);
	}

	

	if (multiBodyB)
	{
		if (solverConstraint.m_linkB<0)
		{
			rel_pos2 = pos2 - multiBodyB->getBasePos();
		} else
		{
			rel_pos2 = pos2 - multiBodyB->getLink(solverConstraint.m_linkB).m_cachedWorldTransform.getOrigin();
		}

		const int ndofB  = (multiBodyB->isMultiDof() ? multiBodyB->getNumDofs() : multiBodyB->getNumLinks()) + 6;

		solverConstraint.m_deltaVelBindex = multiBodyB->getCompanionId();
		if (solverConstraint.m_deltaVelBindex <0)
		{
			solverConstraint.m_deltaVelBindex = m_data.m_deltaVelocities.size();
			multiBodyB->setCompanionId(solverConstraint.m_deltaVelBindex);
			m_data.m_deltaVelocities.resize(m_data.m_deltaVelocities.size()+ndofB);
		}

		solverConstraint.m_jacBindex = m_data.m_jacobians.size();

		m_data.m_jacobians.resize(m_data.m_jacobians.size()+ndofB);
		m_data.m_deltaVelocitiesUnitImpulse.resize(m_data.m_deltaVelocitiesUnitImpulse.size()+ndofB);
		btAssert(m_data.m_jacobians.size() == m_data.m_deltaVelocitiesUnitImpulse.size());

		if(multiBodyB->isMultiDof())
			multiBodyB->fillContactJacobianMultiDof(solverConstraint.m_linkB, cp.getPositionWorldOnB(), -contactNormal, &m_data.m_jacobians[solverConstraint.m_jacBindex], m_data.scratch_r, m_data.scratch_v, m_data.scratch_m);
		else
			multiBodyB->fillContactJacobian(solverConstraint.m_linkB, cp.getPositionWorldOnB(), -contactNormal, &m_data.m_jacobians[solverConstraint.m_jacBindex], m_data.scratch_r, m_data.scratch_v, m_data.scratch_m);
		if(multiBodyB->isMultiDof())
			multiBodyB->calcAccelerationDeltasMultiDof(&m_data.m_jacobians[solverConstraint.m_jacBindex],&m_data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacBindex],m_data.scratch_r, m_data.scratch_v);
		else
			multiBodyB->calcAccelerationDeltas(&m_data.m_jacobians[solverConstraint.m_jacBindex],&m_data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacBindex],m_data.scratch_r, m_data.scratch_v);
		
		btVector3 torqueAxis1 = rel_pos2.cross(contactNormal);		
		solverConstraint.m_relpos2CrossNormal = -torqueAxis1;
		solverConstraint.m_contactNormal2 = -contactNormal;
	
	} else
	{
		btVector3 torqueAxis1 = rel_pos2.cross(contactNormal);		
		solverConstraint.m_relpos2CrossNormal = -torqueAxis1;
		solverConstraint.m_contactNormal2 = -contactNormal;
	
		solverConstraint.m_angularComponentB = rb1 ? rb1->getInvInertiaTensorWorld()*-torqueAxis1*rb1->getAngularFactor() : btVector3(0,0,0);
	}

	{
						
		btVector3 vec;
		btScalar denom0 = 0.f;
		btScalar denom1 = 0.f;
		btScalar* jacB = 0;
		btScalar* jacA = 0;
		btScalar* lambdaA =0;
		btScalar* lambdaB =0;
		int ndofA  = 0;
		if (multiBodyA)
		{
			ndofA  = (multiBodyA->isMultiDof() ? multiBodyA->getNumDofs() : multiBodyA->getNumLinks()) + 6;
			jacA = &m_data.m_jacobians[solverConstraint.m_jacAindex];
			lambdaA = &m_data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacAindex];
			for (int i = 0; i < ndofA; ++i)
			{
				btScalar j = jacA[i] ;
				btScalar l =lambdaA[i];
				denom0 += j*l;
			}
		} else
		{
			if (rb0)
			{
				vec = ( solverConstraint.m_angularComponentA).cross(rel_pos1);
				denom0 = rb0->getInvMass() + contactNormal.dot(vec);
			}
		}
		if (multiBodyB)
		{
			const int ndofB  = (multiBodyB->isMultiDof() ? multiBodyB->getNumDofs() : multiBodyB->getNumLinks()) + 6;
			jacB = &m_data.m_jacobians[solverConstraint.m_jacBindex];
			lambdaB = &m_data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacBindex];
			for (int i = 0; i < ndofB; ++i)
			{
				btScalar j = jacB[i] ;
				btScalar l =lambdaB[i];
				denom1 += j*l;
			}

		} else
		{
			if (rb1)
			{
				vec = ( -solverConstraint.m_angularComponentB).cross(rel_pos2);
				denom1 = rb1->getInvMass() + contactNormal.dot(vec);
			}
		}

		 

		 btScalar d = denom0+denom1;
		 if (d>SIMD_EPSILON)
		 {
			solverConstraint.m_jacDiagABInv = relaxation/(d);
		 } else
		 {
			//disable the constraint row to handle singularity/redundant constraint
			solverConstraint.m_jacDiagABInv  = 0.f;
		 }
		
	}

	
	//compute rhs and remaining solverConstraint fields

	

	btScalar restitution = 0.f;
	btScalar penetration = isFriction? 0 : cp.getDistance()+infoGlobal.m_linearSlop;

	btScalar rel_vel = 0.f;
	int ndofA  = 0;
	int ndofB  = 0;
	{

		btVector3 vel1,vel2;
		if (multiBodyA)
		{
			ndofA  = (multiBodyA->isMultiDof() ? multiBodyA->getNumDofs() : multiBodyA->getNumLinks()) + 6;
			btScalar* jacA = &m_data.m_jacobians[solverConstraint.m_jacAindex];
			for (int i = 0; i < ndofA ; ++i) 
				rel_vel += multiBodyA->getVelocityVector()[i] * jacA[i];
		} else
		{
			if (rb0)
			{
				rel_vel += rb0->getVelocityInLocalPoint(rel_pos1).dot(solverConstraint.m_contactNormal1);
			}
		}
		if (multiBodyB)
		{
			ndofB  = (multiBodyB->isMultiDof() ? multiBodyB->getNumDofs() : multiBodyB->getNumLinks()) + 6;
			btScalar* jacB = &m_data.m_jacobians[solverConstraint.m_jacBindex];
			for (int i = 0; i < ndofB ; ++i) 
				rel_vel += multiBodyB->getVelocityVector()[i] * jacB[i];

		} else
		{
			if (rb1)
			{
				rel_vel += rb1->getVelocityInLocalPoint(rel_pos2).dot(solverConstraint.m_contactNormal2);
			}
		}

		solverConstraint.m_friction = cp.m_combinedFriction;

		if(!isFriction)
		{
			restitution =  restitutionCurve(rel_vel, cp.m_combinedRestitution);	
			if (restitution <= btScalar(0.))
			{
				restitution = 0.f;
			}
		}
	}


	///warm starting (or zero if disabled)
	//disable warmstarting for btMultiBody, it has issues gaining energy (==explosion)
	if (0)//infoGlobal.m_solverMode & SOLVER_USE_WARMSTARTING)
	{
		solverConstraint.m_appliedImpulse = isFriction ? 0 : cp.m_appliedImpulse * infoGlobal.m_warmstartingFactor;

		if (solverConstraint.m_appliedImpulse)
		{
			if (multiBodyA)
			{
				btScalar impulse = solverConstraint.m_appliedImpulse;
				btScalar* deltaV = &m_data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacAindex];
				if(multiBodyA->isMultiDof())
					multiBodyA->applyDeltaVeeMultiDof(deltaV,impulse);
				else
					multiBodyA->applyDeltaVee(deltaV,impulse);
				applyDeltaVee(deltaV,impulse,solverConstraint.m_deltaVelAindex,ndofA);
			} else
			{
				if (rb0)
					bodyA->internalApplyImpulse(solverConstraint.m_contactNormal1*bodyA->internalGetInvMass()*rb0->getLinearFactor(),solverConstraint.m_angularComponentA,solverConstraint.m_appliedImpulse);
			}
			if (multiBodyB)
			{
				btScalar impulse = solverConstraint.m_appliedImpulse;
				btScalar* deltaV = &m_data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacBindex];
				if(multiBodyB->isMultiDof())
					multiBodyB->applyDeltaVeeMultiDof(deltaV,impulse);
				else
					multiBodyB->applyDeltaVee(deltaV,impulse);
				applyDeltaVee(deltaV,impulse,solverConstraint.m_deltaVelBindex,ndofB);
			} else
			{
				if (rb1)
					bodyB->internalApplyImpulse(-solverConstraint.m_contactNormal2*bodyB->internalGetInvMass()*rb1->getLinearFactor(),-solverConstraint.m_angularComponentB,-(btScalar)solverConstraint.m_appliedImpulse);
			}
		}
	} else
	{
		solverConstraint.m_appliedImpulse = 0.f;
	}

	solverConstraint.m_appliedPushImpulse = 0.f;

	{

		btScalar positionalError = 0.f;
		btScalar velocityError = restitution - rel_vel;// * damping;	//note for friction restitution is always set to 0 (check above) so it is acutally velocityError = -rel_vel for friction

		btScalar erp = infoGlobal.m_erp2;
		if (!infoGlobal.m_splitImpulse || (penetration > infoGlobal.m_splitImpulsePenetrationThreshold))
		{
			erp = infoGlobal.m_erp;
		}

		if (penetration>0)
		{
			positionalError = 0;
			velocityError -= penetration / infoGlobal.m_timeStep;

		} else
		{
			positionalError = -penetration * erp/infoGlobal.m_timeStep;
		}

		btScalar  penetrationImpulse = positionalError*solverConstraint.m_jacDiagABInv;
		btScalar velocityImpulse = velocityError *solverConstraint.m_jacDiagABInv;

		if(!isFriction)
		{
			if (!infoGlobal.m_splitImpulse || (penetration > infoGlobal.m_splitImpulsePenetrationThreshold))
			{
				//combine position and velocity into rhs
				solverConstraint.m_rhs = penetrationImpulse+velocityImpulse;
				solverConstraint.m_rhsPenetration = 0.f;

			} else
			{
				//split position and velocity into rhs and m_rhsPenetration
				solverConstraint.m_rhs = velocityImpulse;
				solverConstraint.m_rhsPenetration = penetrationImpulse;
			}

			solverConstraint.m_lowerLimit = 0;
			solverConstraint.m_upperLimit = 1e10f;
		}
		else
		{
			solverConstraint.m_rhs = velocityImpulse;
			solverConstraint.m_rhsPenetration = 0.f;
			solverConstraint.m_lowerLimit = -solverConstraint.m_friction;
			solverConstraint.m_upperLimit = solverConstraint.m_friction;
		}

		solverConstraint.m_cfm = 0.f;			//why not use cfmSlip?
	}

}
/// Changes a btManifoldPoint collision normal to the normal from the mesh.
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);
		}
	}
}
Esempio n. 3
0
bool GameWorld::ContactProcessedCallback(btManifoldPoint &mp, void *body0, void *body1)
{
	auto obA = static_cast<btCollisionObject*>(body0);
	auto obB = static_cast<btCollisionObject*>(body1);

	if( !( obA->getUserPointer() && obB->getUserPointer() ) ) {
		return false;
	}

	GameObject* a = static_cast<GameObject*>(obA->getUserPointer());
	GameObject* b = static_cast<GameObject*>(obB->getUserPointer());

	bool valA = a && a->type() == GameObject::Instance;
	bool valB = b && b->type() == GameObject::Instance;

	if( ! (valA && valB) &&	(valB || valA) ) {

		// Figure out which is the dynamic instance.
		InstanceObject* dynInst = nullptr;
		const btRigidBody* instBody = nullptr, * otherBody = nullptr;

		btVector3 src, dmg;

		if( valA ) {
			dynInst = static_cast<InstanceObject*>(a);
			instBody = static_cast<const btRigidBody*>(obA);
			otherBody = static_cast<const btRigidBody*>(obB);
			src = mp.getPositionWorldOnB();
			dmg = mp.getPositionWorldOnA();
		}
		else {
			dynInst = static_cast<InstanceObject*>(b);
			instBody = static_cast<const btRigidBody*>(obB);
			otherBody = static_cast<const btRigidBody*>(obA);
			src = mp.getPositionWorldOnA();
			dmg = mp.getPositionWorldOnB();
		}

		if( dynInst->dynamics != nullptr && instBody->isStaticObject() ) {
			// Attempt to determine relative velocity.
			auto dV  = (otherBody->getLinearVelocity());
			auto impulse = dV.length()/ (otherBody->getInvMass());

			if( dynInst->dynamics->uprootForce <= impulse ) {
				dynInst->takeDamage({
										{dmg.x(), dmg.y(), dmg.z()},
										{src.x(), src.y(), src.z()},
										0.f,
										GameObject::DamageInfo::Physics,
										impulse
									});
			}
		}
	}

	// Handle vehicles
	if(a) handleVehicleResponse(a, mp, true);
	if(b) handleVehicleResponse(b, mp, false);

	return true;
}