MultiSource/Benchmarks/Bullet/btCompoundCollisionAlgorithm.cpp - llvm-test-suite - Git at Google

 /*
 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.
 */

 #include "BulletCollision/CollisionDispatch/btCompoundCollisionAlgorithm.h"
 #include "BulletCollision/CollisionDispatch/btCollisionObject.h"
 #include "BulletCollision/CollisionShapes/btCompoundShape.h"
 #include "BulletCollision/BroadphaseCollision/btDbvt.h"
 #include "LinearMath/btIDebugDraw.h"
 #include "LinearMath/btAabbUtil2.h"
 #include "BulletCollision/CollisionDispatch/btManifoldResult.h"

 btCompoundCollisionAlgorithm::btCompoundCollisionAlgorithm( const btCollisionAlgorithmConstructionInfo& ci,btCollisionObject* body0,btCollisionObject* body1,bool isSwapped)
 :btActivatingCollisionAlgorithm(ci,body0,body1),
 m_isSwapped(isSwapped),
 m_sharedManifold(ci.m_manifold)
 {
 	m_ownsManifold = false;

 	btCollisionObject* colObj = m_isSwapped? body1 : body0;
 	btAssert (colObj->getCollisionShape()->isCompound());

 	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(colObj->getCollisionShape());
 	m_compoundShapeRevision = compoundShape->getUpdateRevision();

 	preallocateChildAlgorithms(body0,body1);
 }

 void	btCompoundCollisionAlgorithm::preallocateChildAlgorithms(btCollisionObject* body0,btCollisionObject* body1)
 {
 	btCollisionObject* colObj = m_isSwapped? body1 : body0;
 	btCollisionObject* otherObj = m_isSwapped? body0 : body1;
 	btAssert (colObj->getCollisionShape()->isCompound());

 	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(colObj->getCollisionShape());

 	int numChildren = compoundShape->getNumChildShapes();
 	int i;

 	m_childCollisionAlgorithms.resize(numChildren);
 	for (i=0;i<numChildren;i++)
 	{
 		if (compoundShape->getDynamicAabbTree())
 		{
 			m_childCollisionAlgorithms[i] = 0;
 		} else
 		{
 			btCollisionShape* tmpShape = colObj->getCollisionShape();
 			btCollisionShape* childShape = compoundShape->getChildShape(i);
 			colObj->internalSetTemporaryCollisionShape( childShape );
 			m_childCollisionAlgorithms[i] = m_dispatcher->findAlgorithm(colObj,otherObj,m_sharedManifold);
 			colObj->internalSetTemporaryCollisionShape( tmpShape );
 		}
 	}
 }

 void	btCompoundCollisionAlgorithm::removeChildAlgorithms()
 {
 	int numChildren = m_childCollisionAlgorithms.size();
 	int i;
 	for (i=0;i<numChildren;i++)
 	{
 		if (m_childCollisionAlgorithms[i])
 		{
 			m_childCollisionAlgorithms[i]->~btCollisionAlgorithm();
 			m_dispatcher->freeCollisionAlgorithm(m_childCollisionAlgorithms[i]);
 		}
 	}
 }

 btCompoundCollisionAlgorithm::~btCompoundCollisionAlgorithm()
 {
 	removeChildAlgorithms();
 }


 struct	btCompoundLeafCallback : btDbvt::ICollide
 {

 public:

 	btCollisionObject* m_compoundColObj;
 	btCollisionObject* m_otherObj;
 	btDispatcher* m_dispatcher;
 	const btDispatcherInfo& m_dispatchInfo;
 	btManifoldResult*	m_resultOut;
 	btCollisionAlgorithm**	m_childCollisionAlgorithms;
 	btPersistentManifold*	m_sharedManifold;


 	btCompoundLeafCallback (btCollisionObject* compoundObj,btCollisionObject* otherObj,btDispatcher* dispatcher,const btDispatcherInfo& dispatchInfo,btManifoldResult*	resultOut,btCollisionAlgorithm**	childCollisionAlgorithms,btPersistentManifold*	sharedManifold)
 		:m_compoundColObj(compoundObj),m_otherObj(otherObj),m_dispatcher(dispatcher),m_dispatchInfo(dispatchInfo),m_resultOut(resultOut),
 		m_childCollisionAlgorithms(childCollisionAlgorithms),
 		m_sharedManifold(sharedManifold)
 	{

 	}


 	void	ProcessChildShape(btCollisionShape* childShape,int index)
 	{

 		btCompoundShape* compoundShape = static_cast<btCompoundShape*>(m_compoundColObj->getCollisionShape());


 		//backup
 		btTransform	orgTrans = m_compoundColObj->getWorldTransform();
 		btTransform	orgInterpolationTrans = m_compoundColObj->getInterpolationWorldTransform();
 		const btTransform& childTrans = compoundShape->getChildTransform(index);
 		btTransform	newChildWorldTrans = orgTrans*childTrans ;

 		//perform an AABB check first
 		btVector3 aabbMin0,aabbMax0,aabbMin1,aabbMax1;
 		childShape->getAabb(newChildWorldTrans,aabbMin0,aabbMax0);
 		m_otherObj->getCollisionShape()->getAabb(m_otherObj->getWorldTransform(),aabbMin1,aabbMax1);

 		if (TestAabbAgainstAabb2(aabbMin0,aabbMax0,aabbMin1,aabbMax1))
 		{

 			m_compoundColObj->setWorldTransform( newChildWorldTrans);
 			m_compoundColObj->setInterpolationWorldTransform(newChildWorldTrans);

 			//the contactpoint is still projected back using the original inverted worldtrans
 			btCollisionShape* tmpShape = m_compoundColObj->getCollisionShape();
 			m_compoundColObj->internalSetTemporaryCollisionShape( childShape );

 			if (!m_childCollisionAlgorithms[index])
 				m_childCollisionAlgorithms[index] = m_dispatcher->findAlgorithm(m_compoundColObj,m_otherObj,m_sharedManifold);

 			///detect swapping case
 			if (m_resultOut->getBody0Internal() == m_compoundColObj)
 			{
 				m_resultOut->setShapeIdentifiersA(-1,index);
 			} else
 			{
 				m_resultOut->setShapeIdentifiersB(-1,index);
 			}

 			m_childCollisionAlgorithms[index]->processCollision(m_compoundColObj,m_otherObj,m_dispatchInfo,m_resultOut);
 			if (m_dispatchInfo.m_debugDraw && (m_dispatchInfo.m_debugDraw->getDebugMode() & btIDebugDraw::DBG_DrawAabb))
 			{
 				btVector3 worldAabbMin,worldAabbMax;
 				m_dispatchInfo.m_debugDraw->drawAabb(aabbMin0,aabbMax0,btVector3(1,1,1));
 				m_dispatchInfo.m_debugDraw->drawAabb(aabbMin1,aabbMax1,btVector3(1,1,1));
 			}

 			//revert back transform
 			m_compoundColObj->internalSetTemporaryCollisionShape( tmpShape);
 			m_compoundColObj->setWorldTransform(  orgTrans );
 			m_compoundColObj->setInterpolationWorldTransform(orgInterpolationTrans);
 		}
 	}
 	void		Process(const btDbvtNode* leaf)
 	{
 		int index = leaf->dataAsInt;

 		btCompoundShape* compoundShape = static_cast<btCompoundShape*>(m_compoundColObj->getCollisionShape());
 		btCollisionShape* childShape = compoundShape->getChildShape(index);
 		if (m_dispatchInfo.m_debugDraw && (m_dispatchInfo.m_debugDraw->getDebugMode() & btIDebugDraw::DBG_DrawAabb))
 		{
 			btVector3 worldAabbMin,worldAabbMax;
 			btTransform	orgTrans = m_compoundColObj->getWorldTransform();
 			btTransformAabb(leaf->volume.Mins(),leaf->volume.Maxs(),0.,orgTrans,worldAabbMin,worldAabbMax);
 			m_dispatchInfo.m_debugDraw->drawAabb(worldAabbMin,worldAabbMax,btVector3(1,0,0));
 		}
 		ProcessChildShape(childShape,index);

 	}
 };


 void btCompoundCollisionAlgorithm::processCollision (btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
 {
 	btCollisionObject* colObj = m_isSwapped? body1 : body0;
 	btCollisionObject* otherObj = m_isSwapped? body0 : body1;


 	btAssert (colObj->getCollisionShape()->isCompound());
 	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(colObj->getCollisionShape());

 	///btCompoundShape might have changed:
 	////make sure the internal child collision algorithm caches are still valid
 	if (compoundShape->getUpdateRevision() != m_compoundShapeRevision)
 	{
 		///clear and update all
 		removeChildAlgorithms();

 		preallocateChildAlgorithms(body0,body1);
 	}


 	btDbvt* tree = compoundShape->getDynamicAabbTree();
 	//use a dynamic aabb tree to cull potential child-overlaps
 	btCompoundLeafCallback  callback(colObj,otherObj,m_dispatcher,dispatchInfo,resultOut,&m_childCollisionAlgorithms[0],m_sharedManifold);

 	///we need to refresh all contact manifolds
 	///note that we should actually recursively traverse all children, btCompoundShape can nested more then 1 level deep
 	///so we should add a 'refreshManifolds' in the btCollisionAlgorithm
 	{
 		int i;
 		btManifoldArray manifoldArray;
 		for (i=0;i<m_childCollisionAlgorithms.size();i++)
 		{
 			if (m_childCollisionAlgorithms[i])
 			{
 				m_childCollisionAlgorithms[i]->getAllContactManifolds(manifoldArray);
 				for (int m=0;m<manifoldArray.size();m++)
 				{
 					if (manifoldArray[m]->getNumContacts())
 					{
 						resultOut->setPersistentManifold(manifoldArray[m]);
 						resultOut->refreshContactPoints();
 						resultOut->setPersistentManifold(0);//??necessary?
 					}
 				}
 				manifoldArray.clear();
 			}
 		}
 	}

 	if (tree)
 	{

 		btVector3 localAabbMin,localAabbMax;
 		btTransform otherInCompoundSpace;
 		otherInCompoundSpace = colObj->getWorldTransform().inverse() * otherObj->getWorldTransform();
 		otherObj->getCollisionShape()->getAabb(otherInCompoundSpace,localAabbMin,localAabbMax);

 		const ATTRIBUTE_ALIGNED16(btDbvtVolume)	bounds=btDbvtVolume::FromMM(localAabbMin,localAabbMax);
 		//process all children, that overlap with  the given AABB bounds
 		tree->collideTV(tree->m_root,bounds,callback);

 	} else
 	{
 		//iterate over all children, perform an AABB check inside ProcessChildShape
 		int numChildren = m_childCollisionAlgorithms.size();
 		int i;
 		for (i=0;i<numChildren;i++)
 		{
 			callback.ProcessChildShape(compoundShape->getChildShape(i),i);
 		}
 	}

 	{
 				//iterate over all children, perform an AABB check inside ProcessChildShape
 		int numChildren = m_childCollisionAlgorithms.size();
 		int i;
 		btManifoldArray	manifoldArray;

 		for (i=0;i<numChildren;i++)
 		{
 			if (m_childCollisionAlgorithms[i])
 			{
 				btCollisionShape* childShape = compoundShape->getChildShape(i);
 			//if not longer overlapping, remove the algorithm
 				btTransform	orgTrans = colObj->getWorldTransform();
 				btTransform	orgInterpolationTrans = colObj->getInterpolationWorldTransform();
 				const btTransform& childTrans = compoundShape->getChildTransform(i);
 				btTransform	newChildWorldTrans = orgTrans*childTrans ;

 				//perform an AABB check first
 				btVector3 aabbMin0,aabbMax0,aabbMin1,aabbMax1;
 				childShape->getAabb(newChildWorldTrans,aabbMin0,aabbMax0);
 				otherObj->getCollisionShape()->getAabb(otherObj->getWorldTransform(),aabbMin1,aabbMax1);

 				if (!TestAabbAgainstAabb2(aabbMin0,aabbMax0,aabbMin1,aabbMax1))
 				{
 					m_childCollisionAlgorithms[i]->~btCollisionAlgorithm();
 					m_dispatcher->freeCollisionAlgorithm(m_childCollisionAlgorithms[i]);
 					m_childCollisionAlgorithms[i] = 0;
 				}

 			}

 		}


 	}
 }

 btScalar	btCompoundCollisionAlgorithm::calculateTimeOfImpact(btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
 {

 	btCollisionObject* colObj = m_isSwapped? body1 : body0;
 	btCollisionObject* otherObj = m_isSwapped? body0 : body1;

 	btAssert (colObj->getCollisionShape()->isCompound());

 	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(colObj->getCollisionShape());

 	//We will use the OptimizedBVH, AABB tree to cull potential child-overlaps
 	//If both proxies are Compound, we will deal with that directly, by performing sequential/parallel tree traversals
 	//given Proxy0 and Proxy1, if both have a tree, Tree0 and Tree1, this means:
 	//determine overlapping nodes of Proxy1 using Proxy0 AABB against Tree1
 	//then use each overlapping node AABB against Tree0
 	//and vise versa.

 	btScalar hitFraction = btScalar(1.);

 	int numChildren = m_childCollisionAlgorithms.size();
 	int i;
 	for (i=0;i<numChildren;i++)
 	{
 		//temporarily exchange parent btCollisionShape with childShape, and recurse
 		btCollisionShape* childShape = compoundShape->getChildShape(i);

 		//backup
 		btTransform	orgTrans = colObj->getWorldTransform();

 		const btTransform& childTrans = compoundShape->getChildTransform(i);
 		//btTransform	newChildWorldTrans = orgTrans*childTrans ;
 		colObj->setWorldTransform( orgTrans*childTrans );

 		btCollisionShape* tmpShape = colObj->getCollisionShape();
 		colObj->internalSetTemporaryCollisionShape( childShape );
 		btScalar frac = m_childCollisionAlgorithms[i]->calculateTimeOfImpact(colObj,otherObj,dispatchInfo,resultOut);
 		if (frac<hitFraction)
 		{
 			hitFraction = frac;
 		}
 		//revert back
 		colObj->internalSetTemporaryCollisionShape( tmpShape);
 		colObj->setWorldTransform( orgTrans);
 	}
 	return hitFraction;

 }
	/*
	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.
	*/

	#include "BulletCollision/CollisionDispatch/btCompoundCollisionAlgorithm.h"
	#include "BulletCollision/CollisionDispatch/btCollisionObject.h"
	#include "BulletCollision/CollisionShapes/btCompoundShape.h"
	#include "BulletCollision/BroadphaseCollision/btDbvt.h"
	#include "LinearMath/btIDebugDraw.h"
	#include "LinearMath/btAabbUtil2.h"
	#include "BulletCollision/CollisionDispatch/btManifoldResult.h"

	btCompoundCollisionAlgorithm::btCompoundCollisionAlgorithm( const btCollisionAlgorithmConstructionInfo& ci,btCollisionObject* body0,btCollisionObject* body1,bool isSwapped)
	:btActivatingCollisionAlgorithm(ci,body0,body1),
	m_isSwapped(isSwapped),
	m_sharedManifold(ci.m_manifold)
	{
	m_ownsManifold = false;

	btCollisionObject* colObj = m_isSwapped? body1 : body0;
	btAssert (colObj->getCollisionShape()->isCompound());

	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(colObj->getCollisionShape());
	m_compoundShapeRevision = compoundShape->getUpdateRevision();

	preallocateChildAlgorithms(body0,body1);
	}

	void btCompoundCollisionAlgorithm::preallocateChildAlgorithms(btCollisionObject* body0,btCollisionObject* body1)
	{
	btCollisionObject* colObj = m_isSwapped? body1 : body0;
	btCollisionObject* otherObj = m_isSwapped? body0 : body1;
	btAssert (colObj->getCollisionShape()->isCompound());

	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(colObj->getCollisionShape());

	int numChildren = compoundShape->getNumChildShapes();
	int i;

	m_childCollisionAlgorithms.resize(numChildren);
	for (i=0;i<numChildren;i++)
	{
	if (compoundShape->getDynamicAabbTree())
	{
	m_childCollisionAlgorithms[i] = 0;
	} else
	{
	btCollisionShape* tmpShape = colObj->getCollisionShape();
	btCollisionShape* childShape = compoundShape->getChildShape(i);
	colObj->internalSetTemporaryCollisionShape( childShape );
	m_childCollisionAlgorithms[i] = m_dispatcher->findAlgorithm(colObj,otherObj,m_sharedManifold);
	colObj->internalSetTemporaryCollisionShape( tmpShape );
	}
	}
	}

	void btCompoundCollisionAlgorithm::removeChildAlgorithms()
	{
	int numChildren = m_childCollisionAlgorithms.size();
	int i;
	for (i=0;i<numChildren;i++)
	{
	if (m_childCollisionAlgorithms[i])
	{
	m_childCollisionAlgorithms[i]->~btCollisionAlgorithm();
	m_dispatcher->freeCollisionAlgorithm(m_childCollisionAlgorithms[i]);
	}
	}
	}

	btCompoundCollisionAlgorithm::~btCompoundCollisionAlgorithm()
	{
	removeChildAlgorithms();
	}




	struct btCompoundLeafCallback : btDbvt::ICollide
	{

	public:

	btCollisionObject* m_compoundColObj;
	btCollisionObject* m_otherObj;
	btDispatcher* m_dispatcher;
	const btDispatcherInfo& m_dispatchInfo;
	btManifoldResult* m_resultOut;
	btCollisionAlgorithm** m_childCollisionAlgorithms;
	btPersistentManifold* m_sharedManifold;




	btCompoundLeafCallback (btCollisionObject* compoundObj,btCollisionObject* otherObj,btDispatcher* dispatcher,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut,btCollisionAlgorithm** childCollisionAlgorithms,btPersistentManifold* sharedManifold)
	:m_compoundColObj(compoundObj),m_otherObj(otherObj),m_dispatcher(dispatcher),m_dispatchInfo(dispatchInfo),m_resultOut(resultOut),
	m_childCollisionAlgorithms(childCollisionAlgorithms),
	m_sharedManifold(sharedManifold)
	{

	}


	void ProcessChildShape(btCollisionShape* childShape,int index)
	{

	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(m_compoundColObj->getCollisionShape());


	//backup
	btTransform orgTrans = m_compoundColObj->getWorldTransform();
	btTransform orgInterpolationTrans = m_compoundColObj->getInterpolationWorldTransform();
	const btTransform& childTrans = compoundShape->getChildTransform(index);
	btTransform newChildWorldTrans = orgTrans*childTrans ;

	//perform an AABB check first
	btVector3 aabbMin0,aabbMax0,aabbMin1,aabbMax1;
	childShape->getAabb(newChildWorldTrans,aabbMin0,aabbMax0);
	m_otherObj->getCollisionShape()->getAabb(m_otherObj->getWorldTransform(),aabbMin1,aabbMax1);

	if (TestAabbAgainstAabb2(aabbMin0,aabbMax0,aabbMin1,aabbMax1))
	{

	m_compoundColObj->setWorldTransform( newChildWorldTrans);
	m_compoundColObj->setInterpolationWorldTransform(newChildWorldTrans);

	//the contactpoint is still projected back using the original inverted worldtrans
	btCollisionShape* tmpShape = m_compoundColObj->getCollisionShape();
	m_compoundColObj->internalSetTemporaryCollisionShape( childShape );

	if (!m_childCollisionAlgorithms[index])
	m_childCollisionAlgorithms[index] = m_dispatcher->findAlgorithm(m_compoundColObj,m_otherObj,m_sharedManifold);

	///detect swapping case
	if (m_resultOut->getBody0Internal() == m_compoundColObj)
	{
	m_resultOut->setShapeIdentifiersA(-1,index);
	} else
	{
	m_resultOut->setShapeIdentifiersB(-1,index);
	}

	m_childCollisionAlgorithms[index]->processCollision(m_compoundColObj,m_otherObj,m_dispatchInfo,m_resultOut);
	if (m_dispatchInfo.m_debugDraw && (m_dispatchInfo.m_debugDraw->getDebugMode() & btIDebugDraw::DBG_DrawAabb))
	{
	btVector3 worldAabbMin,worldAabbMax;
	m_dispatchInfo.m_debugDraw->drawAabb(aabbMin0,aabbMax0,btVector3(1,1,1));
	m_dispatchInfo.m_debugDraw->drawAabb(aabbMin1,aabbMax1,btVector3(1,1,1));
	}

	//revert back transform
	m_compoundColObj->internalSetTemporaryCollisionShape( tmpShape);
	m_compoundColObj->setWorldTransform( orgTrans );
	m_compoundColObj->setInterpolationWorldTransform(orgInterpolationTrans);
	}
	}
	void Process(const btDbvtNode* leaf)
	{
	int index = leaf->dataAsInt;

	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(m_compoundColObj->getCollisionShape());
	btCollisionShape* childShape = compoundShape->getChildShape(index);
	if (m_dispatchInfo.m_debugDraw && (m_dispatchInfo.m_debugDraw->getDebugMode() & btIDebugDraw::DBG_DrawAabb))
	{
	btVector3 worldAabbMin,worldAabbMax;
	btTransform orgTrans = m_compoundColObj->getWorldTransform();
	btTransformAabb(leaf->volume.Mins(),leaf->volume.Maxs(),0.,orgTrans,worldAabbMin,worldAabbMax);
	m_dispatchInfo.m_debugDraw->drawAabb(worldAabbMin,worldAabbMax,btVector3(1,0,0));
	}
	ProcessChildShape(childShape,index);

	}
	};






	void btCompoundCollisionAlgorithm::processCollision (btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
	{
	btCollisionObject* colObj = m_isSwapped? body1 : body0;
	btCollisionObject* otherObj = m_isSwapped? body0 : body1;



	btAssert (colObj->getCollisionShape()->isCompound());
	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(colObj->getCollisionShape());

	///btCompoundShape might have changed:
	////make sure the internal child collision algorithm caches are still valid
	if (compoundShape->getUpdateRevision() != m_compoundShapeRevision)
	{
	///clear and update all
	removeChildAlgorithms();

	preallocateChildAlgorithms(body0,body1);
	}


	btDbvt* tree = compoundShape->getDynamicAabbTree();
	//use a dynamic aabb tree to cull potential child-overlaps
	btCompoundLeafCallback callback(colObj,otherObj,m_dispatcher,dispatchInfo,resultOut,&m_childCollisionAlgorithms[0],m_sharedManifold);

	///we need to refresh all contact manifolds
	///note that we should actually recursively traverse all children, btCompoundShape can nested more then 1 level deep
	///so we should add a 'refreshManifolds' in the btCollisionAlgorithm
	{
	int i;
	btManifoldArray manifoldArray;
	for (i=0;i<m_childCollisionAlgorithms.size();i++)
	{
	if (m_childCollisionAlgorithms[i])
	{
	m_childCollisionAlgorithms[i]->getAllContactManifolds(manifoldArray);
	for (int m=0;m<manifoldArray.size();m++)
	{
	if (manifoldArray[m]->getNumContacts())
	{
	resultOut->setPersistentManifold(manifoldArray[m]);
	resultOut->refreshContactPoints();
	resultOut->setPersistentManifold(0);//??necessary?
	}
	}
	manifoldArray.clear();
	}
	}
	}

	if (tree)
	{

	btVector3 localAabbMin,localAabbMax;
	btTransform otherInCompoundSpace;
	otherInCompoundSpace = colObj->getWorldTransform().inverse() * otherObj->getWorldTransform();
	otherObj->getCollisionShape()->getAabb(otherInCompoundSpace,localAabbMin,localAabbMax);

	const ATTRIBUTE_ALIGNED16(btDbvtVolume) bounds=btDbvtVolume::FromMM(localAabbMin,localAabbMax);
	//process all children, that overlap with the given AABB bounds
	tree->collideTV(tree->m_root,bounds,callback);

	} else
	{
	//iterate over all children, perform an AABB check inside ProcessChildShape
	int numChildren = m_childCollisionAlgorithms.size();
	int i;
	for (i=0;i<numChildren;i++)
	{
	callback.ProcessChildShape(compoundShape->getChildShape(i),i);
	}
	}

	{
	//iterate over all children, perform an AABB check inside ProcessChildShape
	int numChildren = m_childCollisionAlgorithms.size();
	int i;
	btManifoldArray manifoldArray;

	for (i=0;i<numChildren;i++)
	{
	if (m_childCollisionAlgorithms[i])
	{
	btCollisionShape* childShape = compoundShape->getChildShape(i);
	//if not longer overlapping, remove the algorithm
	btTransform orgTrans = colObj->getWorldTransform();
	btTransform orgInterpolationTrans = colObj->getInterpolationWorldTransform();
	const btTransform& childTrans = compoundShape->getChildTransform(i);
	btTransform newChildWorldTrans = orgTrans*childTrans ;

	//perform an AABB check first
	btVector3 aabbMin0,aabbMax0,aabbMin1,aabbMax1;
	childShape->getAabb(newChildWorldTrans,aabbMin0,aabbMax0);
	otherObj->getCollisionShape()->getAabb(otherObj->getWorldTransform(),aabbMin1,aabbMax1);

	if (!TestAabbAgainstAabb2(aabbMin0,aabbMax0,aabbMin1,aabbMax1))
	{
	m_childCollisionAlgorithms[i]->~btCollisionAlgorithm();
	m_dispatcher->freeCollisionAlgorithm(m_childCollisionAlgorithms[i]);
	m_childCollisionAlgorithms[i] = 0;
	}

	}

	}



	}
	}

	btScalar btCompoundCollisionAlgorithm::calculateTimeOfImpact(btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
	{

	btCollisionObject* colObj = m_isSwapped? body1 : body0;
	btCollisionObject* otherObj = m_isSwapped? body0 : body1;

	btAssert (colObj->getCollisionShape()->isCompound());

	btCompoundShape* compoundShape = static_cast<btCompoundShape*>(colObj->getCollisionShape());

	//We will use the OptimizedBVH, AABB tree to cull potential child-overlaps
	//If both proxies are Compound, we will deal with that directly, by performing sequential/parallel tree traversals
	//given Proxy0 and Proxy1, if both have a tree, Tree0 and Tree1, this means:
	//determine overlapping nodes of Proxy1 using Proxy0 AABB against Tree1
	//then use each overlapping node AABB against Tree0
	//and vise versa.

	btScalar hitFraction = btScalar(1.);

	int numChildren = m_childCollisionAlgorithms.size();
	int i;
	for (i=0;i<numChildren;i++)
	{
	//temporarily exchange parent btCollisionShape with childShape, and recurse
	btCollisionShape* childShape = compoundShape->getChildShape(i);

	//backup
	btTransform orgTrans = colObj->getWorldTransform();

	const btTransform& childTrans = compoundShape->getChildTransform(i);
	//btTransform newChildWorldTrans = orgTrans*childTrans ;
	colObj->setWorldTransform( orgTrans*childTrans );

	btCollisionShape* tmpShape = colObj->getCollisionShape();
	colObj->internalSetTemporaryCollisionShape( childShape );
	btScalar frac = m_childCollisionAlgorithms[i]->calculateTimeOfImpact(colObj,otherObj,dispatchInfo,resultOut);
	if (frac<hitFraction)
	{
	hitFraction = frac;
	}
	//revert back
	colObj->internalSetTemporaryCollisionShape( tmpShape);
	colObj->setWorldTransform( orgTrans);
	}
	return hitFraction;

	}