Add faster processing of btCompoundShape versus btCompoundShape, using a dedicated btCompoundCompoundCollisionAlgorithm,

with hash pair caching and tandem tree traversal. It should be much faster, when using many child shapes for both compounds.
Fix iOS compilation, added header.

src/BulletCollision/BroadphaseCollision/btOverlappingPairCache.cpp

@@ -53,7 +53,7 @@ btHashedOverlappingPairCache::~btHashedOverlappingPairCache()
 
 void	btHashedOverlappingPairCache::cleanOverlappingPair(btBroadphasePair& pair,btDispatcher* dispatcher)
 {
-	if (pair.m_algorithm)
+	if (pair.m_algorithm && dispatcher)
 	{
 		{
 			pair.m_algorithm->~btCollisionAlgorithm();

src/BulletCollision/BroadphaseCollision/btOverlappingPairCache.h

@@ -96,6 +96,12 @@ class btHashedOverlappingPairCache : public btOverlappingPairCache
 	btOverlapFilterCallback* m_overlapFilterCallback;
 	bool		m_blockedForChanges;
 
+protected:
+	
+	btAlignedObjectArray<int>	m_hashTable;
+	btAlignedObjectArray<int>	m_next;
+	btOverlappingPairCallback*	m_ghostPairCallback;
+
 
 public:
 	btHashedOverlappingPairCache();
@@ -265,11 +271,6 @@ private:
 	virtual void	sortOverlappingPairs(btDispatcher* dispatcher);
 	
 
-protected:
-	
-	btAlignedObjectArray<int>	m_hashTable;
-	btAlignedObjectArray<int>	m_next;
-	btOverlappingPairCallback*	m_ghostPairCallback;
 	
 };
 

src/BulletCollision/CMakeLists.txt

@@ -19,6 +19,7 @@ SET(BulletCollision_SRCS
 	CollisionDispatch/btCollisionObject.cpp
 	CollisionDispatch/btCollisionWorld.cpp
 	CollisionDispatch/btCompoundCollisionAlgorithm.cpp
+	CollisionDispatch/btCompoundCompoundCollisionAlgorithm.cpp
 	CollisionDispatch/btConvexConcaveCollisionAlgorithm.cpp
 	CollisionDispatch/btConvexConvexAlgorithm.cpp
 	CollisionDispatch/btConvexPlaneCollisionAlgorithm.cpp
@@ -26,6 +27,7 @@ SET(BulletCollision_SRCS
 	CollisionDispatch/btDefaultCollisionConfiguration.cpp
 	CollisionDispatch/btEmptyCollisionAlgorithm.cpp
 	CollisionDispatch/btGhostObject.cpp
+	CollisionDispatch/btHashedSimplePairCache.cpp
 	CollisionDispatch/btInternalEdgeUtility.cpp
 	CollisionDispatch/btInternalEdgeUtility.h
 	CollisionDispatch/btManifoldResult.cpp
@@ -125,6 +127,7 @@ SET(CollisionDispatch_HDRS
 	CollisionDispatch/btCollisionObjectWrapper.h
 	CollisionDispatch/btCollisionWorld.h
 	CollisionDispatch/btCompoundCollisionAlgorithm.h
+	CollisionDispatch/btCompoundCompoundCollisionAlgorithm.h
 	CollisionDispatch/btConvexConcaveCollisionAlgorithm.h
 	CollisionDispatch/btConvexConvexAlgorithm.h
 	CollisionDispatch/btConvex2dConvex2dAlgorithm.h
@@ -132,6 +135,7 @@ SET(CollisionDispatch_HDRS
 	CollisionDispatch/btDefaultCollisionConfiguration.h
 	CollisionDispatch/btEmptyCollisionAlgorithm.h
 	CollisionDispatch/btGhostObject.h
+	CollisionDispatch/btHashedSimplePairCache.h
 	CollisionDispatch/btManifoldResult.h
 	CollisionDispatch/btSimulationIslandManager.h
 	CollisionDispatch/btSphereBoxCollisionAlgorithm.h

src/BulletCollision/CollisionDispatch/btCompoundCompoundCollisionAlgorithm.cpp

@@ -0,0 +1,421 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2013 Erwin Coumans  http://bulletphysics.org
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+
+*/
+
+#include "btCompoundCompoundCollisionAlgorithm.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"
+#include "BulletCollision/CollisionDispatch/btCollisionObjectWrapper.h"
+
+
+btShapePairCallback gCompoundCompoundChildShapePairCallback = 0;
+
+btCompoundCompoundCollisionAlgorithm::btCompoundCompoundCollisionAlgorithm( const btCollisionAlgorithmConstructionInfo& ci,const btCollisionObjectWrapper* body0Wrap,const btCollisionObjectWrapper* body1Wrap,bool isSwapped)
+:btActivatingCollisionAlgorithm(ci,body0Wrap,body1Wrap),
+m_sharedManifold(ci.m_manifold)
+{
+	m_ownsManifold = false;
+
+	void* ptr = btAlignedAlloc(sizeof(btHashedSimplePairCache),16);
+	m_childCollisionAlgorithmCache= new(ptr) btHashedSimplePairCache();
+
+	const btCollisionObjectWrapper* col0ObjWrap = body0Wrap;
+	btAssert (col0ObjWrap->getCollisionShape()->isCompound());
+
+	const btCollisionObjectWrapper* col1ObjWrap = body1Wrap;
+	btAssert (col1ObjWrap->getCollisionShape()->isCompound());
+	
+	const btCompoundShape* compoundShape0 = static_cast<const btCompoundShape*>(col0ObjWrap->getCollisionShape());
+	m_compoundShapeRevision0 = compoundShape0->getUpdateRevision();
+
+	const btCompoundShape* compoundShape1 = static_cast<const btCompoundShape*>(col1ObjWrap->getCollisionShape());
+	m_compoundShapeRevision1 = compoundShape1->getUpdateRevision();
+	
+	
+}
+
+
+btCompoundCompoundCollisionAlgorithm::~btCompoundCompoundCollisionAlgorithm()
+{
+	removeChildAlgorithms();
+	m_childCollisionAlgorithmCache->~btHashedSimplePairCache();
+	btAlignedFree(m_childCollisionAlgorithmCache);
+}
+
+void	btCompoundCompoundCollisionAlgorithm::getAllContactManifolds(btManifoldArray&	manifoldArray)
+{
+	int i;
+	btSimplePairArray& pairs = m_childCollisionAlgorithmCache->getOverlappingPairArray();
+	for (i=0;i<pairs.size();i++)
+	{
+		if (pairs[i].m_userPointer)
+		{
+			
+			((btCollisionAlgorithm*)pairs[i].m_userPointer)->getAllContactManifolds(manifoldArray);
+		}
+	}
+}
+
+
+void	btCompoundCompoundCollisionAlgorithm::removeChildAlgorithms()
+{
+	btSimplePairArray& pairs = m_childCollisionAlgorithmCache->getOverlappingPairArray();
+
+	int numChildren = pairs.size();
+	int i;
+	for (i=0;i<numChildren;i++)
+	{
+		if (pairs[i].m_userPointer)
+		{
+			btCollisionAlgorithm* algo = (btCollisionAlgorithm*) pairs[i].m_userPointer;
+			algo->~btCollisionAlgorithm();
+			m_dispatcher->freeCollisionAlgorithm(algo);
+		}
+	}
+	m_childCollisionAlgorithmCache->removeAllPairs();
+}
+
+struct	btCompoundCompoundLeafCallback : btDbvt::ICollide
+{
+	int m_numOverlapPairs;
+
+
+	const btCollisionObjectWrapper* m_compound0ColObjWrap;
+	const btCollisionObjectWrapper* m_compound1ColObjWrap;
+	btDispatcher* m_dispatcher;
+	const btDispatcherInfo& m_dispatchInfo;
+	btManifoldResult*	m_resultOut;
+	
+	
+	class btHashedSimplePairCache*	m_childCollisionAlgorithmCache;
+	
+	btPersistentManifold*	m_sharedManifold;
+	
+	btCompoundCompoundLeafCallback (const btCollisionObjectWrapper* compound1ObjWrap,
+									const btCollisionObjectWrapper* compound0ObjWrap,
+									btDispatcher* dispatcher,
+									const btDispatcherInfo& dispatchInfo,
+									btManifoldResult*	resultOut,
+									btHashedSimplePairCache* childAlgorithmsCache,
+									btPersistentManifold*	sharedManifold)
+		:m_compound0ColObjWrap(compound1ObjWrap),m_compound1ColObjWrap(compound0ObjWrap),m_dispatcher(dispatcher),m_dispatchInfo(dispatchInfo),m_resultOut(resultOut),
+		m_childCollisionAlgorithmCache(childAlgorithmsCache),
+		m_sharedManifold(sharedManifold),
+		m_numOverlapPairs(0)
+	{
+
+	}
+
+
+
+	
+	void		Process(const btDbvtNode* leaf0,const btDbvtNode* leaf1)
+	{
+		m_numOverlapPairs++;
+
+
+		int childIndex0 = leaf0->dataAsInt;
+		int childIndex1 = leaf1->dataAsInt;
+		
+
+		btAssert(childIndex0>=0);
+		btAssert(childIndex1>=0);
+
+
+		const btCompoundShape* compoundShape0 = static_cast<const btCompoundShape*>(m_compound0ColObjWrap->getCollisionShape());
+		btAssert(childIndex0<compoundShape0->getNumChildShapes());
+
+		const btCompoundShape* compoundShape1 = static_cast<const btCompoundShape*>(m_compound1ColObjWrap->getCollisionShape());
+		btAssert(childIndex1<compoundShape1->getNumChildShapes());
+
+		const btCollisionShape* childShape0 = compoundShape0->getChildShape(childIndex0);
+		const btCollisionShape* childShape1 = compoundShape1->getChildShape(childIndex1);
+
+		//backup
+		btTransform	orgTrans0 = m_compound0ColObjWrap->getWorldTransform();
+		const btTransform& childTrans0 = compoundShape0->getChildTransform(childIndex0);
+		btTransform	newChildWorldTrans0 = orgTrans0*childTrans0 ;
+		
+		btTransform	orgTrans1 = m_compound1ColObjWrap->getWorldTransform();
+		const btTransform& childTrans1 = compoundShape1->getChildTransform(childIndex1);
+		btTransform	newChildWorldTrans1 = orgTrans1*childTrans1 ;
+		
+
+		//perform an AABB check first
+		btVector3 aabbMin0,aabbMax0,aabbMin1,aabbMax1;
+		childShape0->getAabb(newChildWorldTrans0,aabbMin0,aabbMax0);
+		childShape1->getAabb(newChildWorldTrans1,aabbMin1,aabbMax1);
+		
+		if (gCompoundCompoundChildShapePairCallback)
+		{
+			if (!gCompoundCompoundChildShapePairCallback(childShape0,childShape1))
+				return;
+		}
+
+		if (TestAabbAgainstAabb2(aabbMin0,aabbMax0,aabbMin1,aabbMax1))
+		{
+			btCollisionObjectWrapper compoundWrap0(this->m_compound0ColObjWrap,childShape0, m_compound0ColObjWrap->getCollisionObject(),newChildWorldTrans0,-1,childIndex0);
+			btCollisionObjectWrapper compoundWrap1(this->m_compound1ColObjWrap,childShape1,m_compound1ColObjWrap->getCollisionObject(),newChildWorldTrans1,-1,childIndex1);
+			
+
+			btSimplePair* pair = m_childCollisionAlgorithmCache->findPair(childIndex0,childIndex1);
+
+			btCollisionAlgorithm* colAlgo = 0;
+
+			if (pair)
+			{
+				colAlgo = (btCollisionAlgorithm*)pair->m_userPointer;
+				
+			} else
+			{
+				colAlgo = m_dispatcher->findAlgorithm(&compoundWrap0,&compoundWrap1,m_sharedManifold);
+				pair = m_childCollisionAlgorithmCache->addOverlappingPair(childIndex0,childIndex1);
+				btAssert(pair);
+				pair->m_userPointer = colAlgo;
+			}
+
+			btAssert(colAlgo);
+						
+			const btCollisionObjectWrapper* tmpWrap0 = 0;
+			const btCollisionObjectWrapper* tmpWrap1 = 0;
+
+			tmpWrap0 = m_resultOut->getBody0Wrap();
+			tmpWrap1 = m_resultOut->getBody1Wrap();
+
+			m_resultOut->setBody0Wrap(&compoundWrap0);
+			m_resultOut->setBody1Wrap(&compoundWrap1);
+
+			m_resultOut->setShapeIdentifiersA(-1,childIndex0);
+			m_resultOut->setShapeIdentifiersB(-1,childIndex1);
+
+
+			colAlgo->processCollision(&compoundWrap0,&compoundWrap1,m_dispatchInfo,m_resultOut);
+			
+			m_resultOut->setBody0Wrap(tmpWrap0);
+			m_resultOut->setBody1Wrap(tmpWrap1);
+			
+
+
+		}
+	}
+};
+
+
+static DBVT_INLINE bool		MyIntersect(	const btDbvtAabbMm& a,
+								  const btDbvtAabbMm& b, const btTransform& xform)
+{
+	btVector3 newmin,newmax;
+	btTransformAabb(b.Mins(),b.Maxs(),0.f,xform,newmin,newmax);
+	btDbvtAabbMm newb = btDbvtAabbMm::FromMM(newmin,newmax);
+	return Intersect(a,newb);
+}
+
+
+static inline void		MycollideTT(	const btDbvtNode* root0,
+								  const btDbvtNode* root1,
+								  const btTransform& xform,
+								  btCompoundCompoundLeafCallback* callback)
+{
+
+		if(root0&&root1)
+		{
+			int								depth=1;
+			int								treshold=btDbvt::DOUBLE_STACKSIZE-4;
+			btAlignedObjectArray<btDbvt::sStkNN>	stkStack;
+			stkStack.resize(btDbvt::DOUBLE_STACKSIZE);
+			stkStack[0]=btDbvt::sStkNN(root0,root1);
+			do	{
+				btDbvt::sStkNN	p=stkStack[--depth];
+				if(MyIntersect(p.a->volume,p.b->volume,xform))
+				{
+					if(depth>treshold)
+					{
+						stkStack.resize(stkStack.size()*2);
+						treshold=stkStack.size()-4;
+					}
+					if(p.a->isinternal())
+					{
+						if(p.b->isinternal())
+						{					
+							stkStack[depth++]=btDbvt::sStkNN(p.a->childs[0],p.b->childs[0]);
+							stkStack[depth++]=btDbvt::sStkNN(p.a->childs[1],p.b->childs[0]);
+							stkStack[depth++]=btDbvt::sStkNN(p.a->childs[0],p.b->childs[1]);
+							stkStack[depth++]=btDbvt::sStkNN(p.a->childs[1],p.b->childs[1]);
+						}
+						else
+						{
+							stkStack[depth++]=btDbvt::sStkNN(p.a->childs[0],p.b);
+							stkStack[depth++]=btDbvt::sStkNN(p.a->childs[1],p.b);
+						}
+					}
+					else
+					{
+						if(p.b->isinternal())
+						{
+							stkStack[depth++]=btDbvt::sStkNN(p.a,p.b->childs[0]);
+							stkStack[depth++]=btDbvt::sStkNN(p.a,p.b->childs[1]);
+						}
+						else
+						{
+							callback->Process(p.a,p.b);
+						}
+					}
+				}
+			} while(depth);
+		}
+}
+
+void btCompoundCompoundCollisionAlgorithm::processCollision (const btCollisionObjectWrapper* body0Wrap,const btCollisionObjectWrapper* body1Wrap,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
+{
+
+	const btCollisionObjectWrapper* col0ObjWrap = body0Wrap;
+	const btCollisionObjectWrapper* col1ObjWrap= body1Wrap;
+
+	btAssert (col0ObjWrap->getCollisionShape()->isCompound());
+	btAssert (col1ObjWrap->getCollisionShape()->isCompound());
+	const btCompoundShape* compoundShape0 = static_cast<const btCompoundShape*>(col0ObjWrap->getCollisionShape());
+	const btCompoundShape* compoundShape1 = static_cast<const btCompoundShape*>(col1ObjWrap->getCollisionShape());
+
+	///btCompoundShape might have changed:
+	////make sure the internal child collision algorithm caches are still valid
+	if ((compoundShape0->getUpdateRevision() != m_compoundShapeRevision0) || (compoundShape1->getUpdateRevision() != m_compoundShapeRevision1))
+	{
+		///clear all
+		removeChildAlgorithms();
+	}
+
+
+	///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;
+		btSimplePairArray& pairs = m_childCollisionAlgorithmCache->getOverlappingPairArray();
+		for (i=0;i<pairs.size();i++)
+		{
+			if (pairs[i].m_userPointer)
+			{
+				btCollisionAlgorithm* algo = (btCollisionAlgorithm*) pairs[i].m_userPointer;
+				algo->getAllContactManifolds(manifoldArray);
+				for (int m=0;m<manifoldArray.size();m++)
+				{
+					if (manifoldArray[m]->getNumContacts())
+					{
+						resultOut->setPersistentManifold(manifoldArray[m]);
+						resultOut->refreshContactPoints();
+						resultOut->setPersistentManifold(0);
+					}
+				}
+				manifoldArray.resize(0);
+			}
+		}
+	}
+
+
+	const btDbvt* tree0 = compoundShape0->getDynamicAabbTree();
+	const btDbvt* tree1 = compoundShape1->getDynamicAabbTree();
+
+	btCompoundCompoundLeafCallback callback(col0ObjWrap,col1ObjWrap,this->m_dispatcher,dispatchInfo,resultOut,this->m_childCollisionAlgorithmCache,m_sharedManifold);
+
+
+	const btTransform	xform=col0ObjWrap->getWorldTransform().inverse()*col1ObjWrap->getWorldTransform();
+	MycollideTT(tree0->m_root,tree1->m_root,xform,&callback);
+
+	//printf("#compound-compound child/leaf overlap =%d                      \r",callback.m_numOverlapPairs);
+
+	//remove non-overlapping child pairs
+
+	{
+		btAssert(m_removePairs.size()==0);
+
+		//iterate over all children, perform an AABB check inside ProcessChildShape
+		btSimplePairArray& pairs = m_childCollisionAlgorithmCache->getOverlappingPairArray();
+		
+		int i;
+		btManifoldArray	manifoldArray;
+        
+		
+
+        
+        
+        btVector3 aabbMin0,aabbMax0,aabbMin1,aabbMax1;        
+        
+		for (i=0;i<pairs.size();i++)
+		{
+			if (pairs[i].m_userPointer)
+			{
+				btCollisionAlgorithm* algo = (btCollisionAlgorithm*)pairs[i].m_userPointer;
+
+				{
+					btTransform	orgTrans0;
+					const btCollisionShape* childShape0 = 0;
+					
+					btTransform	newChildWorldTrans0;
+					btTransform	orgInterpolationTrans0;
+					childShape0 = compoundShape0->getChildShape(pairs[i].m_indexA);
+					orgTrans0 = col0ObjWrap->getWorldTransform();
+					orgInterpolationTrans0 = col0ObjWrap->getWorldTransform();
+					const btTransform& childTrans0 = compoundShape0->getChildTransform(pairs[i].m_indexA);
+					newChildWorldTrans0 = orgTrans0*childTrans0 ;
+					childShape0->getAabb(newChildWorldTrans0,aabbMin0,aabbMax0);
+				}
+
+				{
+					btTransform	orgInterpolationTrans1;
+					const btCollisionShape* childShape1 = 0;
+					btTransform	orgTrans1;
+					btTransform	newChildWorldTrans1;
+
+					childShape1 = compoundShape1->getChildShape(pairs[i].m_indexB);
+					orgTrans1 = col1ObjWrap->getWorldTransform();
+					orgInterpolationTrans1 = col1ObjWrap->getWorldTransform();
+					const btTransform& childTrans1 = compoundShape1->getChildTransform(pairs[i].m_indexB);
+					newChildWorldTrans1 = orgTrans1*childTrans1 ;
+					childShape1->getAabb(newChildWorldTrans1,aabbMin1,aabbMax1);
+				}
+				
+				
+
+				if (!TestAabbAgainstAabb2(aabbMin0,aabbMax0,aabbMin1,aabbMax1))
+				{
+					algo->~btCollisionAlgorithm();
+					m_dispatcher->freeCollisionAlgorithm(algo);
+					m_removePairs.push_back(btSimplePair(pairs[i].m_indexA,pairs[i].m_indexB));
+				}
+			}
+		}
+		for (int i=0;i<m_removePairs.size();i++)
+		{
+			m_childCollisionAlgorithmCache->removeOverlappingPair(m_removePairs[i].m_indexA,m_removePairs[i].m_indexB);
+		}
+		m_removePairs.clear();
+	}
+
+}
+
+btScalar	btCompoundCompoundCollisionAlgorithm::calculateTimeOfImpact(btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
+{
+	btAssert(0);
+	return 0.f;
+
+}
+
+
+

src/BulletCollision/CollisionDispatch/btCompoundCompoundCollisionAlgorithm.h

@@ -0,0 +1,90 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2013 Erwin Coumans  http://bulletphysics.org
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+
+*/
+
+#ifndef BT_COMPOUND_COMPOUND_COLLISION_ALGORITHM_H
+#define BT_COMPOUND_COMPOUND_COLLISION_ALGORITHM_H
+
+#include "BulletCollision/CollisionDispatch/btActivatingCollisionAlgorithm.h"
+#include "BulletCollision/BroadphaseCollision/btDispatcher.h"
+#include "BulletCollision/BroadphaseCollision/btBroadphaseInterface.h"
+
+#include "BulletCollision/NarrowPhaseCollision/btPersistentManifold.h"
+class btDispatcher;
+#include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h"
+#include "BulletCollision/CollisionDispatch/btCollisionCreateFunc.h"
+#include "LinearMath/btAlignedObjectArray.h"
+#include "BulletCollision/CollisionDispatch/btHashedSimplePairCache.h"
+class btDispatcher;
+class btCollisionObject;
+
+class btCollisionShape;
+typedef bool (*btShapePairCallback)(const btCollisionShape* pShape0, const btCollisionShape* pShape1);
+extern btShapePairCallback gCompoundCompoundChildShapePairCallback;
+
+/// btCompoundCompoundCollisionAlgorithm  supports collision between two btCompoundCollisionShape shapes
+class btCompoundCompoundCollisionAlgorithm  : public btActivatingCollisionAlgorithm
+{
+
+	class btHashedSimplePairCache*	m_childCollisionAlgorithmCache;
+	btSimplePairArray m_removePairs;
+
+	class btPersistentManifold*	m_sharedManifold;
+	bool					m_ownsManifold;
+
+
+	int	m_compoundShapeRevision0;//to keep track of changes, so that childAlgorithm array can be updated
+	int	m_compoundShapeRevision1;
+	
+	void	removeChildAlgorithms();
+	
+//	void	preallocateChildAlgorithms(const btCollisionObjectWrapper* body0Wrap,const btCollisionObjectWrapper* body1Wrap);
+
+public:
+
+	btCompoundCompoundCollisionAlgorithm( const btCollisionAlgorithmConstructionInfo& ci,const btCollisionObjectWrapper* body0Wrap,const btCollisionObjectWrapper* body1Wrap,bool isSwapped);
+
+	virtual ~btCompoundCompoundCollisionAlgorithm();
+
+	
+
+	virtual void processCollision (const btCollisionObjectWrapper* body0Wrap,const btCollisionObjectWrapper* body1Wrap,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut);
+
+	btScalar	calculateTimeOfImpact(btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut);
+
+	virtual	void	getAllContactManifolds(btManifoldArray&	manifoldArray);
+	
+	
+	struct CreateFunc :public 	btCollisionAlgorithmCreateFunc
+	{
+		virtual	btCollisionAlgorithm* CreateCollisionAlgorithm(btCollisionAlgorithmConstructionInfo& ci, const btCollisionObjectWrapper* body0Wrap,const btCollisionObjectWrapper* body1Wrap)
+		{
+			void* mem = ci.m_dispatcher1->allocateCollisionAlgorithm(sizeof(btCompoundCompoundCollisionAlgorithm));
+			return new(mem) btCompoundCompoundCollisionAlgorithm(ci,body0Wrap,body1Wrap,false);
+		}
+	};
+
+	struct SwappedCreateFunc :public 	btCollisionAlgorithmCreateFunc
+	{
+		virtual	btCollisionAlgorithm* CreateCollisionAlgorithm(btCollisionAlgorithmConstructionInfo& ci, const btCollisionObjectWrapper* body0Wrap,const btCollisionObjectWrapper* body1Wrap)
+		{
+			void* mem = ci.m_dispatcher1->allocateCollisionAlgorithm(sizeof(btCompoundCompoundCollisionAlgorithm));
+			return new(mem) btCompoundCompoundCollisionAlgorithm(ci,body0Wrap,body1Wrap,true);
+		}
+	};
+
+};
+
+#endif //BT_COMPOUND_COMPOUND_COLLISION_ALGORITHM_H

src/BulletCollision/CollisionDispatch/btDefaultCollisionConfiguration.cpp

@@ -19,6 +19,8 @@ subject to the following restrictions:
 #include "BulletCollision/CollisionDispatch/btEmptyCollisionAlgorithm.h"
 #include "BulletCollision/CollisionDispatch/btConvexConcaveCollisionAlgorithm.h"
 #include "BulletCollision/CollisionDispatch/btCompoundCollisionAlgorithm.h"
+#include "BulletCollision/CollisionDispatch/btCompoundCompoundCollisionAlgorithm.h"
+
 #include "BulletCollision/CollisionDispatch/btConvexPlaneCollisionAlgorithm.h"
 #include "BulletCollision/CollisionDispatch/btBoxBoxCollisionAlgorithm.h"
 #include "BulletCollision/CollisionDispatch/btSphereSphereCollisionAlgorithm.h"
@@ -64,6 +66,10 @@ btDefaultCollisionConfiguration::btDefaultCollisionConfiguration(const btDefault
 	m_swappedConvexConcaveCreateFunc = new (mem)btConvexConcaveCollisionAlgorithm::SwappedCreateFunc;
 	mem = btAlignedAlloc(sizeof(btCompoundCollisionAlgorithm::CreateFunc),16);
 	m_compoundCreateFunc = new (mem)btCompoundCollisionAlgorithm::CreateFunc;
+
+	mem = btAlignedAlloc(sizeof(btCompoundCompoundCollisionAlgorithm::CreateFunc),16);
+	m_compoundCompoundCreateFunc = new (mem)btCompoundCompoundCollisionAlgorithm::CreateFunc;
+
 	mem = btAlignedAlloc(sizeof(btCompoundCollisionAlgorithm::SwappedCreateFunc),16);
 	m_swappedCompoundCreateFunc = new (mem)btCompoundCollisionAlgorithm::SwappedCreateFunc;
 	mem = btAlignedAlloc(sizeof(btEmptyAlgorithm::CreateFunc),16);
@@ -155,6 +161,9 @@ btDefaultCollisionConfiguration::~btDefaultCollisionConfiguration()
 	m_compoundCreateFunc->~btCollisionAlgorithmCreateFunc();
 	btAlignedFree( m_compoundCreateFunc);
 
+	m_compoundCompoundCreateFunc->~btCollisionAlgorithmCreateFunc();
+	btAlignedFree(m_compoundCompoundCreateFunc);
+
 	m_swappedCompoundCreateFunc->~btCollisionAlgorithmCreateFunc();
 	btAlignedFree( m_swappedCompoundCreateFunc);
 
@@ -258,6 +267,12 @@ btCollisionAlgorithmCreateFunc* btDefaultCollisionConfiguration::getCollisionAlg
 		return m_swappedConvexConcaveCreateFunc;
 	}
 
+
+	if (btBroadphaseProxy::isCompound(proxyType0) && btBroadphaseProxy::isCompound(proxyType1))
+	{
+		return m_compoundCompoundCreateFunc;
+	}
+
 	if (btBroadphaseProxy::isCompound(proxyType0))
 	{
 		return m_compoundCreateFunc;

src/BulletCollision/CollisionDispatch/btDefaultCollisionConfiguration.h

@@ -69,6 +69,8 @@ protected:
 	btCollisionAlgorithmCreateFunc*	m_convexConcaveCreateFunc;
 	btCollisionAlgorithmCreateFunc*	m_swappedConvexConcaveCreateFunc;
 	btCollisionAlgorithmCreateFunc*	m_compoundCreateFunc;
+	btCollisionAlgorithmCreateFunc*	m_compoundCompoundCreateFunc;
+	
 	btCollisionAlgorithmCreateFunc*	m_swappedCompoundCreateFunc;
 	btCollisionAlgorithmCreateFunc* m_emptyCreateFunc;
 	btCollisionAlgorithmCreateFunc* m_sphereSphereCF;

src/BulletCollision/CollisionDispatch/btHashedSimplePairCache.cpp

@@ -0,0 +1,278 @@
+/*
+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 "btHashedSimplePairCache.h"
+
+
+#include <stdio.h>
+
+int	gOverlappingSimplePairs = 0;
+int gRemoveSimplePairs =0;
+int gAddedSimplePairs =0;
+int gFindSimplePairs =0;
+
+
+
+
+btHashedSimplePairCache::btHashedSimplePairCache():
+	m_blockedForChanges(false)
+{
+	int initialAllocatedSize= 2;
+	m_overlappingPairArray.reserve(initialAllocatedSize);
+	growTables();
+}
+
+
+
+
+btHashedSimplePairCache::~btHashedSimplePairCache()
+{
+}
+
+
+
+
+
+
+void btHashedSimplePairCache::removeAllPairs()
+{
+	m_overlappingPairArray.clear();
+	m_hashTable.clear();
+	m_next.clear();
+
+	int initialAllocatedSize= 2;
+	m_overlappingPairArray.reserve(initialAllocatedSize);
+	growTables();
+}
+
+
+
+btSimplePair* btHashedSimplePairCache::findPair(int indexA, int indexB)
+{
+	gFindSimplePairs++;
+	
+	
+	/*if (indexA > indexB) 
+		btSwap(indexA, indexB);*/
+
+	int hash = static_cast<int>(getHash(static_cast<unsigned int>(indexA), static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity()-1));
+
+	if (hash >= m_hashTable.size())
+	{
+		return NULL;
+	}
+
+	int index = m_hashTable[hash];
+	while (index != BT_SIMPLE_NULL_PAIR && equalsPair(m_overlappingPairArray[index], indexA, indexB) == false)
+	{
+		index = m_next[index];
+	}
+
+	if (index == BT_SIMPLE_NULL_PAIR)
+	{
+		return NULL;
+	}
+
+	btAssert(index < m_overlappingPairArray.size());
+
+	return &m_overlappingPairArray[index];
+}
+
+//#include <stdio.h>
+
+void	btHashedSimplePairCache::growTables()
+{
+
+	int newCapacity = m_overlappingPairArray.capacity();
+
+	if (m_hashTable.size() < newCapacity)
+	{
+		//grow hashtable and next table
+		int curHashtableSize = m_hashTable.size();
+
+		m_hashTable.resize(newCapacity);
+		m_next.resize(newCapacity);
+
+
+		int i;
+
+		for (i= 0; i < newCapacity; ++i)
+		{
+			m_hashTable[i] = BT_SIMPLE_NULL_PAIR;
+		}
+		for (i = 0; i < newCapacity; ++i)
+		{
+			m_next[i] = BT_SIMPLE_NULL_PAIR;
+		}
+
+		for(i=0;i<curHashtableSize;i++)
+		{
+	
+			const btSimplePair& pair = m_overlappingPairArray[i];
+			int indexA = pair.m_indexA;
+			int indexB = pair.m_indexB;
+			
+			int	hashValue = static_cast<int>(getHash(static_cast<unsigned int>(indexA),static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity()-1));	// New hash value with new mask
+			m_next[i] = m_hashTable[hashValue];
+			m_hashTable[hashValue] = i;
+		}
+
+
+	}
+}
+
+btSimplePair* btHashedSimplePairCache::internalAddPair(int indexA, int indexB)
+{
+
+	int	hash = static_cast<int>(getHash(static_cast<unsigned int>(indexA),static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity()-1));	// New hash value with new mask
+
+
+	btSimplePair* pair = internalFindPair(indexA, indexB, hash);
+	if (pair != NULL)
+	{
+		return pair;
+	}
+
+	int count = m_overlappingPairArray.size();
+	int oldCapacity = m_overlappingPairArray.capacity();
+	void* mem = &m_overlappingPairArray.expandNonInitializing();
+
+	int newCapacity = m_overlappingPairArray.capacity();
+
+	if (oldCapacity < newCapacity)
+	{
+		growTables();
+		//hash with new capacity
+		hash = static_cast<int>(getHash(static_cast<unsigned int>(indexA),static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity()-1));
+	}
+	
+	pair = new (mem) btSimplePair(indexA,indexB);
+
+	pair->m_userPointer = 0;
+	
+	m_next[count] = m_hashTable[hash];
+	m_hashTable[hash] = count;
+
+	return pair;
+}
+
+
+
+void* btHashedSimplePairCache::removeOverlappingPair(int indexA, int indexB)
+{
+	gRemoveSimplePairs++;
+	
+
+	/*if (indexA > indexB) 
+		btSwap(indexA, indexB);*/
+
+	int	hash = static_cast<int>(getHash(static_cast<unsigned int>(indexA),static_cast<unsigned int>(indexB)) & (m_overlappingPairArray.capacity()-1));
+
+	btSimplePair* pair = internalFindPair(indexA, indexB, hash);
+	if (pair == NULL)
+	{
+		return 0;
+	}
+
+	
+	void* userData = pair->m_userPointer;
+
+
+	int pairIndex = int(pair - &m_overlappingPairArray[0]);
+	btAssert(pairIndex < m_overlappingPairArray.size());
+
+	// Remove the pair from the hash table.
+	int index = m_hashTable[hash];
+	btAssert(index != BT_SIMPLE_NULL_PAIR);
+
+	int previous = BT_SIMPLE_NULL_PAIR;
+	while (index != pairIndex)
+	{
+		previous = index;
+		index = m_next[index];
+	}
+
+	if (previous != BT_SIMPLE_NULL_PAIR)
+	{
+		btAssert(m_next[previous] == pairIndex);
+		m_next[previous] = m_next[pairIndex];
+	}
+	else
+	{
+		m_hashTable[hash] = m_next[pairIndex];
+	}
+
+	// We now move the last pair into spot of the
+	// pair being removed. We need to fix the hash
+	// table indices to support the move.
+
+	int lastPairIndex = m_overlappingPairArray.size() - 1;
+
+	// If the removed pair is the last pair, we are done.
+	if (lastPairIndex == pairIndex)
+	{
+		m_overlappingPairArray.pop_back();
+		return userData;
+	}
+
+	// Remove the last pair from the hash table.
+	const btSimplePair* last = &m_overlappingPairArray[lastPairIndex];
+		/* missing swap here too, Nat. */ 
+	int lastHash = static_cast<int>(getHash(static_cast<unsigned int>(last->m_indexA), static_cast<unsigned int>(last->m_indexB)) & (m_overlappingPairArray.capacity()-1));
+
+	index = m_hashTable[lastHash];
+	btAssert(index != BT_SIMPLE_NULL_PAIR);
+
+	previous = BT_SIMPLE_NULL_PAIR;
+	while (index != lastPairIndex)
+	{
+		previous = index;
+		index = m_next[index];
+	}
+
+	if (previous != BT_SIMPLE_NULL_PAIR)
+	{
+		btAssert(m_next[previous] == lastPairIndex);
+		m_next[previous] = m_next[lastPairIndex];
+	}
+	else
+	{
+		m_hashTable[lastHash] = m_next[lastPairIndex];
+	}
+
+	// Copy the last pair into the remove pair's spot.
+	m_overlappingPairArray[pairIndex] = m_overlappingPairArray[lastPairIndex];
+
+	// Insert the last pair into the hash table
+	m_next[pairIndex] = m_hashTable[lastHash];
+	m_hashTable[lastHash] = pairIndex;
+
+	m_overlappingPairArray.pop_back();
+
+	return userData;
+}
+//#include <stdio.h>
+
+
+
+
+
+
+
+
+
+

src/BulletCollision/CollisionDispatch/btHashedSimplePairCache.h

@@ -0,0 +1,174 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef BT_HASHED_SIMPLE_PAIR_CACHE_H
+#define BT_HASHED_SIMPLE_PAIR_CACHE_H
+
+
+
+#include "LinearMath/btAlignedObjectArray.h"
+
+const int BT_SIMPLE_NULL_PAIR=0xffffffff;
+
+struct btSimplePair
+{
+	btSimplePair(int indexA,int indexB)
+		:m_indexA(indexA),
+		m_indexB(indexB),
+		m_userPointer(0)
+	{
+	}
+
+	int m_indexA;
+	int m_indexB;
+	union
+	{
+		void*	m_userPointer;
+		int		m_userValue;
+	};
+};
+
+typedef btAlignedObjectArray<btSimplePair>	btSimplePairArray;
+
+
+
+extern int gOverlappingSimplePairs;
+extern int gRemoveSimplePairs;
+extern int gAddedSimplePairs;
+extern int gFindSimplePairs;
+
+
+
+
+class btHashedSimplePairCache
+{
+	btSimplePairArray	m_overlappingPairArray;
+	
+	bool		m_blockedForChanges;
+	
+
+protected:
+	
+	btAlignedObjectArray<int>	m_hashTable;
+	btAlignedObjectArray<int>	m_next;
+	
+
+public:
+	btHashedSimplePairCache();
+	virtual ~btHashedSimplePairCache();
+	
+	void removeAllPairs();
+
+	virtual void*	removeOverlappingPair(int indexA,int indexB);
+	
+	// Add a pair and return the new pair. If the pair already exists,
+	// no new pair is created and the old one is returned.
+	virtual btSimplePair* 	addOverlappingPair(int indexA,int indexB)
+	{
+		gAddedSimplePairs++;
+
+		return internalAddPair(indexA,indexB);
+	}
+
+	
+	virtual btSimplePair*	getOverlappingPairArrayPtr()
+	{
+		return &m_overlappingPairArray[0];
+	}
+
+	const btSimplePair*	getOverlappingPairArrayPtr() const
+	{
+		return &m_overlappingPairArray[0];
+	}
+
+	btSimplePairArray&	getOverlappingPairArray()
+	{
+		return m_overlappingPairArray;
+	}
+
+	const btSimplePairArray&	getOverlappingPairArray() const
+	{
+		return m_overlappingPairArray;
+	}
+
+	
+	btSimplePair* findPair(int indexA,int indexB);
+
+	int GetCount() const { return m_overlappingPairArray.size(); }
+
+	int	getNumOverlappingPairs() const
+	{
+		return m_overlappingPairArray.size();
+	}
+private:
+	
+	btSimplePair* 	internalAddPair(int indexA, int indexB);
+
+	void	growTables();
+
+	SIMD_FORCE_INLINE bool equalsPair(const btSimplePair& pair, int indexA, int indexB)
+	{	
+		return pair.m_indexA == indexA && pair.m_indexB == indexB;
+	}
+
+	
+	
+	SIMD_FORCE_INLINE	unsigned int getHash(unsigned int indexA, unsigned int indexB)
+	{
+		int key = static_cast<int>(((unsigned int)indexA) | (((unsigned int)indexB) <<16));
+		// Thomas Wang's hash
+
+		key += ~(key << 15);
+		key ^=  (key >> 10);
+		key +=  (key << 3);
+		key ^=  (key >> 6);
+		key += ~(key << 11);
+		key ^=  (key >> 16);
+		return static_cast<unsigned int>(key);
+	}
+	
+
+
+
+
+	SIMD_FORCE_INLINE btSimplePair* internalFindPair(int proxyIdA , int proxyIdB, int hash)
+	{
+		
+		int index = m_hashTable[hash];
+		
+		while( index != BT_SIMPLE_NULL_PAIR && equalsPair(m_overlappingPairArray[index], proxyIdA, proxyIdB) == false)
+		{
+			index = m_next[index];
+		}
+
+		if ( index == BT_SIMPLE_NULL_PAIR )
+		{
+			return NULL;
+		}
+
+		btAssert(index < m_overlappingPairArray.size());
+
+		return &m_overlappingPairArray[index];
+	}
+
+	
+};
+
+
+
+
+#endif //BT_HASHED_SIMPLE_PAIR_CACHE_H
+
+

src/LinearMath/btVector3.cpp

@@ -823,7 +823,8 @@ long _mindot_large( const float *vv, const float *vec, unsigned long count, floa
 #elif defined BT_USE_NEON
 #define ARM_NEON_GCC_COMPATIBILITY  1
 #include <arm_neon.h>
-
+#include <sys/types.h>
+#include <sys/sysctl.h> //for sysctlbyname
 
 static long _maxdot_large_v0( const float *vv, const float *vec, unsigned long count, float *dotResult );
 static long _maxdot_large_v1( const float *vv, const float *vec, unsigned long count, float *dotResult );

src/Makefile.am

@@ -160,6 +160,8 @@ libBulletCollision_la_SOURCES = \
 		BulletCollision/CollisionDispatch/btConvex2dConvex2dAlgorithm.cpp \
 		BulletCollision/CollisionDispatch/btUnionFind.cpp \
 		BulletCollision/CollisionDispatch/btCompoundCollisionAlgorithm.cpp \
+		BulletCollision/CollisionDispatch/btHashedSimplePairCache.cpp \
+		BulletCollision/CollisionDispatch/btCompoundCompoundCollisionAlgorithm.cpp \
 		BulletCollision/CollisionShapes/btTetrahedronShape.cpp \
 		BulletCollision/CollisionShapes/btShapeHull.cpp \
 		BulletCollision/CollisionShapes/btMinkowskiSumShape.cpp \
@@ -239,6 +241,8 @@ libBulletCollision_la_SOURCES = \
 		BulletCollision/CollisionDispatch/btConvexConcaveCollisionAlgorithm.h \
 		BulletCollision/CollisionDispatch/btUnionFind.h \
 		BulletCollision/CollisionDispatch/btCompoundCollisionAlgorithm.h \
+		BulletCollision/CollisionDispatch/btHashedSimplePairCache.h \
+		BulletCollision/CollisionDispatch/btCompoundCompoundCollisionAlgorithm.h \
 		BulletCollision/CollisionDispatch/btSimulationIslandManager.h \
 		BulletCollision/CollisionDispatch/btDefaultCollisionConfiguration.h \
 		BulletCollision/CollisionDispatch/btCollisionWorld.h \
@@ -501,6 +505,8 @@ nobase_bullet_include_HEADERS += \
 	BulletCollision/CollisionDispatch/btBox2dBox2dCollisionAlgorithm.h \
 	BulletCollision/CollisionDispatch/btDefaultCollisionConfiguration.h \
 	BulletCollision/CollisionDispatch/btCompoundCollisionAlgorithm.h \
+	BulletCollision/CollisionDispatch/btHashedSimplePairCache.h \
+	BulletCollision/CollisionDispatch/btCompoundCompoundCollisionAlgorithm.h \
 	BulletCollision/CollisionDispatch/btSphereBoxCollisionAlgorithm.h \
 	BulletCollision/CollisionDispatch/btGhostObject.h \
 	BulletCollision/CollisionDispatch/btSimulationIslandManager.h \