Add support for generic 2d convex shapes, through wrapper class btConvex2dShape. See Bullet/Demos/Box2dDemo for example wrapping a btCylinderShape and 2d btConvexHullShape.

Add some extra degeneracy debugging check in btGjkPairDetector

src/BulletCollision/BroadphaseCollision/btBroadphaseProxy.h

@@ -46,6 +46,8 @@ IMPLICIT_CONVEX_SHAPES_START_HERE,
 	UNIFORM_SCALING_SHAPE_PROXYTYPE,
 	MINKOWSKI_SUM_SHAPE_PROXYTYPE,
 	MINKOWSKI_DIFFERENCE_SHAPE_PROXYTYPE,
+	BOX_2D_SHAPE_PROXYTYPE,
+	CONVEX_2D_SHAPE_PROXYTYPE,
 	CUSTOM_CONVEX_SHAPE_TYPE,
 //concave shapes
 CONCAVE_SHAPES_START_HERE,
@@ -152,6 +154,12 @@ BT_DECLARE_ALIGNED_ALLOCATOR();
 	{
 		return (proxyType == STATIC_PLANE_PROXYTYPE);
 	}
+
+	static SIMD_FORCE_INLINE bool isConvex2d(int proxyType)
+	{
+		return (proxyType == BOX_2D_SHAPE_PROXYTYPE) ||	(proxyType == CONVEX_2D_SHAPE_PROXYTYPE);
+	}
+
 	
 }
 ;

src/BulletCollision/CollisionDispatch/btBox2dBox2dCollisionAlgorithm.cpp

@@ -0,0 +1,437 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+* The b2CollidePolygons routines are Copyright (c) 2006-2007 Erin Catto http://www.gphysics.com
+
+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.
+*/
+
+///btBox2dBox2dCollisionAlgorithm, with modified b2CollidePolygons routines from the Box2D library.
+///The modifications include: switching from b2Vec to btVector3, redefinition of b2Dot, b2Cross
+
+#include "btBox2dBox2dCollisionAlgorithm.h"
+#include "BulletCollision/CollisionDispatch/btCollisionDispatcher.h"
+#include "BulletCollision/CollisionShapes/btBoxShape.h"
+#include "BulletCollision/CollisionDispatch/btCollisionObject.h"
+#include "BulletCollision/CollisionDispatch/btBoxBoxDetector.h"
+#include "BulletCollision/CollisionShapes/btBox2dShape.h"
+
+#define USE_PERSISTENT_CONTACTS 1
+
+btBox2dBox2dCollisionAlgorithm::btBox2dBox2dCollisionAlgorithm(btPersistentManifold* mf,const btCollisionAlgorithmConstructionInfo& ci,btCollisionObject* obj0,btCollisionObject* obj1)
+: btActivatingCollisionAlgorithm(ci,obj0,obj1),
+m_ownManifold(false),
+m_manifoldPtr(mf)
+{
+	if (!m_manifoldPtr && m_dispatcher->needsCollision(obj0,obj1))
+	{
+		m_manifoldPtr = m_dispatcher->getNewManifold(obj0,obj1);
+		m_ownManifold = true;
+	}
+}
+
+btBox2dBox2dCollisionAlgorithm::~btBox2dBox2dCollisionAlgorithm()
+{
+	
+	if (m_ownManifold)
+	{
+		if (m_manifoldPtr)
+			m_dispatcher->releaseManifold(m_manifoldPtr);
+	}
+	
+}
+
+
+void b2CollidePolygons(btManifoldResult* manifold,  const btBox2dShape* polyA, const btTransform& xfA, const btBox2dShape* polyB, const btTransform& xfB);
+
+//#include <stdio.h>
+void btBox2dBox2dCollisionAlgorithm::processCollision (btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
+{
+	if (!m_manifoldPtr)
+		return;
+
+	btCollisionObject*	col0 = body0;
+	btCollisionObject*	col1 = body1;
+	btBox2dShape* box0 = (btBox2dShape*)col0->getCollisionShape();
+	btBox2dShape* box1 = (btBox2dShape*)col1->getCollisionShape();
+
+	resultOut->setPersistentManifold(m_manifoldPtr);
+
+	b2CollidePolygons(resultOut,box0,col0->getWorldTransform(),box1,col1->getWorldTransform());
+
+	//  refreshContactPoints is only necessary when using persistent contact points. otherwise all points are newly added
+	if (m_ownManifold)
+	{
+		resultOut->refreshContactPoints();
+	}
+
+}
+
+btScalar btBox2dBox2dCollisionAlgorithm::calculateTimeOfImpact(btCollisionObject* /*body0*/,btCollisionObject* /*body1*/,const btDispatcherInfo& /*dispatchInfo*/,btManifoldResult* /*resultOut*/)
+{
+	//not yet
+	return 1.f;
+}
+
+
+struct ClipVertex
+{
+	btVector3 v;
+	int id;
+	//b2ContactID id;
+	//b2ContactID id;
+};
+
+#define b2Dot(a,b) (a).dot(b)
+#define b2Mul(a,b) (a)*(b)
+#define b2MulT(a,b) (a).transpose()*(b)
+#define b2Cross(a,b) (a).cross(b)
+#define btCrossS(a,s) btVector3(s * a.getY(), -s * a.getX(),0.f)
+
+int b2_maxManifoldPoints =2;
+
+static int ClipSegmentToLine(ClipVertex vOut[2], ClipVertex vIn[2],
+					  const btVector3& normal, btScalar offset)
+{
+	// Start with no output points
+	int numOut = 0;
+
+	// Calculate the distance of end points to the line
+	btScalar distance0 = b2Dot(normal, vIn[0].v) - offset;
+	btScalar distance1 = b2Dot(normal, vIn[1].v) - offset;
+
+	// If the points are behind the plane
+	if (distance0 <= 0.0f) vOut[numOut++] = vIn[0];
+	if (distance1 <= 0.0f) vOut[numOut++] = vIn[1];
+
+	// If the points are on different sides of the plane
+	if (distance0 * distance1 < 0.0f)
+	{
+		// Find intersection point of edge and plane
+		btScalar interp = distance0 / (distance0 - distance1);
+		vOut[numOut].v = vIn[0].v + interp * (vIn[1].v - vIn[0].v);
+		if (distance0 > 0.0f)
+		{
+			vOut[numOut].id = vIn[0].id;
+		}
+		else
+		{
+			vOut[numOut].id = vIn[1].id;
+		}
+		++numOut;
+	}
+
+	return numOut;
+}
+
+// Find the separation between poly1 and poly2 for a give edge normal on poly1.
+static btScalar EdgeSeparation(const btBox2dShape* poly1, const btTransform& xf1, int edge1,
+							  const btBox2dShape* poly2, const btTransform& xf2)
+{
+	int count1 = poly1->getVertexCount();
+	const btVector3* vertices1 = poly1->getVertices();
+	const btVector3* normals1 = poly1->getNormals();
+
+	int count2 = poly2->getVertexCount();
+	const btVector3* vertices2 = poly2->getVertices();
+
+	btAssert(0 <= edge1 && edge1 < count1);
+
+	// Convert normal from poly1's frame into poly2's frame.
+	btVector3 normal1World = b2Mul(xf1.getBasis(), normals1[edge1]);
+	btVector3 normal1 = b2MulT(xf2.getBasis(), normal1World);
+
+	// Find support vertex on poly2 for -normal.
+	int index = 0;
+	btScalar minDot = BT_LARGE_FLOAT;
+
+	for (int i = 0; i < count2; ++i)
+	{
+		btScalar dot = b2Dot(vertices2[i], normal1);
+		if (dot < minDot)
+		{
+			minDot = dot;
+			index = i;
+		}
+	}
+
+	btVector3 v1 = b2Mul(xf1, vertices1[edge1]);
+	btVector3 v2 = b2Mul(xf2, vertices2[index]);
+	btScalar separation = b2Dot(v2 - v1, normal1World);
+	return separation;
+}
+
+// Find the max separation between poly1 and poly2 using edge normals from poly1.
+static btScalar FindMaxSeparation(int* edgeIndex,
+								 const btBox2dShape* poly1, const btTransform& xf1,
+								 const btBox2dShape* poly2, const btTransform& xf2)
+{
+	int count1 = poly1->getVertexCount();
+	const btVector3* normals1 = poly1->getNormals();
+
+	// Vector pointing from the centroid of poly1 to the centroid of poly2.
+	btVector3 d = b2Mul(xf2, poly2->getCentroid()) - b2Mul(xf1, poly1->getCentroid());
+	btVector3 dLocal1 = b2MulT(xf1.getBasis(), d);
+
+	// Find edge normal on poly1 that has the largest projection onto d.
+	int edge = 0;
+	btScalar maxDot = -BT_LARGE_FLOAT;
+	for (int i = 0; i < count1; ++i)
+	{
+		btScalar dot = b2Dot(normals1[i], dLocal1);
+		if (dot > maxDot)
+		{
+			maxDot = dot;
+			edge = i;
+		}
+	}
+
+	// Get the separation for the edge normal.
+	btScalar s = EdgeSeparation(poly1, xf1, edge, poly2, xf2);
+	if (s > 0.0f)
+	{
+		return s;
+	}
+
+	// Check the separation for the previous edge normal.
+	int prevEdge = edge - 1 >= 0 ? edge - 1 : count1 - 1;
+	btScalar sPrev = EdgeSeparation(poly1, xf1, prevEdge, poly2, xf2);
+	if (sPrev > 0.0f)
+	{
+		return sPrev;
+	}
+
+	// Check the separation for the next edge normal.
+	int nextEdge = edge + 1 < count1 ? edge + 1 : 0;
+	btScalar sNext = EdgeSeparation(poly1, xf1, nextEdge, poly2, xf2);
+	if (sNext > 0.0f)
+	{
+		return sNext;
+	}
+
+	// Find the best edge and the search direction.
+	int bestEdge;
+	btScalar bestSeparation;
+	int increment;
+	if (sPrev > s && sPrev > sNext)
+	{
+		increment = -1;
+		bestEdge = prevEdge;
+		bestSeparation = sPrev;
+	}
+	else if (sNext > s)
+	{
+		increment = 1;
+		bestEdge = nextEdge;
+		bestSeparation = sNext;
+	}
+	else
+	{
+		*edgeIndex = edge;
+		return s;
+	}
+
+	// Perform a local search for the best edge normal.
+	for ( ; ; )
+	{
+		if (increment == -1)
+			edge = bestEdge - 1 >= 0 ? bestEdge - 1 : count1 - 1;
+		else
+			edge = bestEdge + 1 < count1 ? bestEdge + 1 : 0;
+
+		s = EdgeSeparation(poly1, xf1, edge, poly2, xf2);
+		if (s > 0.0f)
+		{
+			return s;
+		}
+
+		if (s > bestSeparation)
+		{
+			bestEdge = edge;
+			bestSeparation = s;
+		}
+		else
+		{
+			break;
+		}
+	}
+
+	*edgeIndex = bestEdge;
+	return bestSeparation;
+}
+
+static void FindIncidentEdge(ClipVertex c[2],
+							 const btBox2dShape* poly1, const btTransform& xf1, int edge1,
+							 const btBox2dShape* poly2, const btTransform& xf2)
+{
+	int count1 = poly1->getVertexCount();
+	const btVector3* normals1 = poly1->getNormals();
+
+	int count2 = poly2->getVertexCount();
+	const btVector3* vertices2 = poly2->getVertices();
+	const btVector3* normals2 = poly2->getNormals();
+
+	btAssert(0 <= edge1 && edge1 < count1);
+
+	// Get the normal of the reference edge in poly2's frame.
+	btVector3 normal1 = b2MulT(xf2.getBasis(), b2Mul(xf1.getBasis(), normals1[edge1]));
+
+	// Find the incident edge on poly2.
+	int index = 0;
+	btScalar minDot = BT_LARGE_FLOAT;
+	for (int i = 0; i < count2; ++i)
+	{
+		btScalar dot = b2Dot(normal1, normals2[i]);
+		if (dot < minDot)
+		{
+			minDot = dot;
+			index = i;
+		}
+	}
+
+	// Build the clip vertices for the incident edge.
+	int i1 = index;
+	int i2 = i1 + 1 < count2 ? i1 + 1 : 0;
+
+	c[0].v = b2Mul(xf2, vertices2[i1]);
+//	c[0].id.features.referenceEdge = (unsigned char)edge1;
+//	c[0].id.features.incidentEdge = (unsigned char)i1;
+//	c[0].id.features.incidentVertex = 0;
+
+	c[1].v = b2Mul(xf2, vertices2[i2]);
+//	c[1].id.features.referenceEdge = (unsigned char)edge1;
+//	c[1].id.features.incidentEdge = (unsigned char)i2;
+//	c[1].id.features.incidentVertex = 1;
+}
+
+// Find edge normal of max separation on A - return if separating axis is found
+// Find edge normal of max separation on B - return if separation axis is found
+// Choose reference edge as min(minA, minB)
+// Find incident edge
+// Clip
+
+// The normal points from 1 to 2
+void b2CollidePolygons(btManifoldResult* manifold,
+					  const btBox2dShape* polyA, const btTransform& xfA,
+					  const btBox2dShape* polyB, const btTransform& xfB)
+{
+
+	int edgeA = 0;
+	btScalar separationA = FindMaxSeparation(&edgeA, polyA, xfA, polyB, xfB);
+	if (separationA > 0.0f)
+		return;
+
+	int edgeB = 0;
+	btScalar separationB = FindMaxSeparation(&edgeB, polyB, xfB, polyA, xfA);
+	if (separationB > 0.0f)
+		return;
+
+	const btBox2dShape* poly1;	// reference poly
+	const btBox2dShape* poly2;	// incident poly
+	btTransform xf1, xf2;
+	int edge1;		// reference edge
+	unsigned char flip;
+	const btScalar k_relativeTol = 0.98f;
+	const btScalar k_absoluteTol = 0.001f;
+
+	// TODO_ERIN use "radius" of poly for absolute tolerance.
+	if (separationB > k_relativeTol * separationA + k_absoluteTol)
+	{
+		poly1 = polyB;
+		poly2 = polyA;
+		xf1 = xfB;
+		xf2 = xfA;
+		edge1 = edgeB;
+		flip = 1;
+	}
+	else
+	{
+		poly1 = polyA;
+		poly2 = polyB;
+		xf1 = xfA;
+		xf2 = xfB;
+		edge1 = edgeA;
+		flip = 0;
+	}
+
+	ClipVertex incidentEdge[2];
+	FindIncidentEdge(incidentEdge, poly1, xf1, edge1, poly2, xf2);
+
+	int count1 = poly1->getVertexCount();
+	const btVector3* vertices1 = poly1->getVertices();
+
+	btVector3 v11 = vertices1[edge1];
+	btVector3 v12 = edge1 + 1 < count1 ? vertices1[edge1+1] : vertices1[0];
+
+	btVector3 dv = v12 - v11;
+	btVector3 sideNormal = b2Mul(xf1.getBasis(), v12 - v11);
+	sideNormal.normalize();
+	btVector3 frontNormal = btCrossS(sideNormal, 1.0f);
+	
+	
+	v11 = b2Mul(xf1, v11);
+	v12 = b2Mul(xf1, v12);
+
+	btScalar frontOffset = b2Dot(frontNormal, v11);
+	btScalar sideOffset1 = -b2Dot(sideNormal, v11);
+	btScalar sideOffset2 = b2Dot(sideNormal, v12);
+
+	// Clip incident edge against extruded edge1 side edges.
+	ClipVertex clipPoints1[2];
+	clipPoints1[0].v.setValue(0,0,0);
+	clipPoints1[1].v.setValue(0,0,0);
+
+	ClipVertex clipPoints2[2];
+	clipPoints2[0].v.setValue(0,0,0);
+	clipPoints2[1].v.setValue(0,0,0);
+
+
+	int np;
+
+	// Clip to box side 1
+	np = ClipSegmentToLine(clipPoints1, incidentEdge, -sideNormal, sideOffset1);
+
+	if (np < 2)
+		return;
+
+	// Clip to negative box side 1
+	np = ClipSegmentToLine(clipPoints2, clipPoints1,  sideNormal, sideOffset2);
+
+	if (np < 2)
+	{
+		return;
+	}
+
+	// Now clipPoints2 contains the clipped points.
+	btVector3 manifoldNormal = flip ? -frontNormal : frontNormal;
+
+	int pointCount = 0;
+	for (int i = 0; i < b2_maxManifoldPoints; ++i)
+	{
+		btScalar separation = b2Dot(frontNormal, clipPoints2[i].v) - frontOffset;
+
+		if (separation <= 0.0f)
+		{
+			
+			//b2ManifoldPoint* cp = manifold->points + pointCount;
+			//btScalar separation = separation;
+			//cp->localPoint1 = b2MulT(xfA, clipPoints2[i].v);
+			//cp->localPoint2 = b2MulT(xfB, clipPoints2[i].v);
+
+			manifold->addContactPoint(-manifoldNormal,clipPoints2[i].v,separation);
+
+//			cp->id = clipPoints2[i].id;
+//			cp->id.features.flip = flip;
+			++pointCount;
+		}
+	}
+
+//	manifold->pointCount = pointCount;}
+}

src/BulletCollision/CollisionDispatch/btBox2dBox2dCollisionAlgorithm.h

@@ -0,0 +1,66 @@
+/*
+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 BOX_2D_BOX_2D__COLLISION_ALGORITHM_H
+#define BOX_2D_BOX_2D__COLLISION_ALGORITHM_H
+
+#include "BulletCollision/CollisionDispatch/btActivatingCollisionAlgorithm.h"
+#include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h"
+#include "BulletCollision/BroadphaseCollision/btDispatcher.h"
+#include "BulletCollision/CollisionDispatch/btCollisionCreateFunc.h"
+
+class btPersistentManifold;
+
+///box-box collision detection
+class btBox2dBox2dCollisionAlgorithm : public btActivatingCollisionAlgorithm
+{
+	bool	m_ownManifold;
+	btPersistentManifold*	m_manifoldPtr;
+	
+public:
+	btBox2dBox2dCollisionAlgorithm(const btCollisionAlgorithmConstructionInfo& ci)
+		: btActivatingCollisionAlgorithm(ci) {}
+
+	virtual void processCollision (btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut);
+
+	virtual btScalar calculateTimeOfImpact(btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut);
+
+	btBox2dBox2dCollisionAlgorithm(btPersistentManifold* mf,const btCollisionAlgorithmConstructionInfo& ci,btCollisionObject* body0,btCollisionObject* body1);
+
+	virtual ~btBox2dBox2dCollisionAlgorithm();
+
+	virtual	void	getAllContactManifolds(btManifoldArray&	manifoldArray)
+	{
+		if (m_manifoldPtr && m_ownManifold)
+		{
+			manifoldArray.push_back(m_manifoldPtr);
+		}
+	}
+
+
+	struct CreateFunc :public 	btCollisionAlgorithmCreateFunc
+	{
+		virtual	btCollisionAlgorithm* CreateCollisionAlgorithm(btCollisionAlgorithmConstructionInfo& ci, btCollisionObject* body0,btCollisionObject* body1)
+		{
+			int bbsize = sizeof(btBox2dBox2dCollisionAlgorithm);
+			void* ptr = ci.m_dispatcher1->allocateCollisionAlgorithm(bbsize);
+			return new(ptr) btBox2dBox2dCollisionAlgorithm(0,ci,body0,body1);
+		}
+	};
+
+};
+
+#endif //BOX_2D_BOX_2D__COLLISION_ALGORITHM_H
+

src/BulletCollision/CollisionDispatch/btConvex2dConvex2dAlgorithm.cpp

@@ -0,0 +1,247 @@
+/*
+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 "btConvex2dConvex2dAlgorithm.h"
+
+//#include <stdio.h>
+#include "BulletCollision/NarrowPhaseCollision/btDiscreteCollisionDetectorInterface.h"
+#include "BulletCollision/BroadphaseCollision/btBroadphaseInterface.h"
+#include "BulletCollision/CollisionDispatch/btCollisionObject.h"
+#include "BulletCollision/CollisionShapes/btConvexShape.h"
+#include "BulletCollision/CollisionShapes/btCapsuleShape.h"
+
+
+#include "BulletCollision/NarrowPhaseCollision/btGjkPairDetector.h"
+#include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h"
+#include "BulletCollision/CollisionDispatch/btCollisionDispatcher.h"
+#include "BulletCollision/CollisionShapes/btBoxShape.h"
+#include "BulletCollision/CollisionDispatch/btManifoldResult.h"
+
+#include "BulletCollision/NarrowPhaseCollision/btConvexPenetrationDepthSolver.h"
+#include "BulletCollision/NarrowPhaseCollision/btContinuousConvexCollision.h"
+#include "BulletCollision/NarrowPhaseCollision/btSubSimplexConvexCast.h"
+#include "BulletCollision/NarrowPhaseCollision/btGjkConvexCast.h"
+
+
+
+#include "BulletCollision/NarrowPhaseCollision/btVoronoiSimplexSolver.h"
+#include "BulletCollision/CollisionShapes/btSphereShape.h"
+
+#include "BulletCollision/NarrowPhaseCollision/btMinkowskiPenetrationDepthSolver.h"
+
+#include "BulletCollision/NarrowPhaseCollision/btGjkEpa2.h"
+#include "BulletCollision/NarrowPhaseCollision/btGjkEpaPenetrationDepthSolver.h"
+
+
+btConvex2dConvex2dAlgorithm::CreateFunc::CreateFunc(btSimplexSolverInterface*			simplexSolver, btConvexPenetrationDepthSolver* pdSolver)
+{
+	m_numPerturbationIterations = 0;
+	m_minimumPointsPerturbationThreshold = 3;
+	m_simplexSolver = simplexSolver;
+	m_pdSolver = pdSolver;
+}
+
+btConvex2dConvex2dAlgorithm::CreateFunc::~CreateFunc() 
+{ 
+}
+
+btConvex2dConvex2dAlgorithm::btConvex2dConvex2dAlgorithm(btPersistentManifold* mf,const btCollisionAlgorithmConstructionInfo& ci,btCollisionObject* body0,btCollisionObject* body1,btSimplexSolverInterface* simplexSolver, btConvexPenetrationDepthSolver* pdSolver,int numPerturbationIterations, int minimumPointsPerturbationThreshold)
+: btActivatingCollisionAlgorithm(ci,body0,body1),
+m_simplexSolver(simplexSolver),
+m_pdSolver(pdSolver),
+m_ownManifold (false),
+m_manifoldPtr(mf),
+m_lowLevelOfDetail(false),
+ m_numPerturbationIterations(numPerturbationIterations),
+m_minimumPointsPerturbationThreshold(minimumPointsPerturbationThreshold)
+{
+	(void)body0;
+	(void)body1;
+}
+
+
+
+
+btConvex2dConvex2dAlgorithm::~btConvex2dConvex2dAlgorithm()
+{
+	if (m_ownManifold)
+	{
+		if (m_manifoldPtr)
+			m_dispatcher->releaseManifold(m_manifoldPtr);
+	}
+}
+
+void	btConvex2dConvex2dAlgorithm ::setLowLevelOfDetail(bool useLowLevel)
+{
+	m_lowLevelOfDetail = useLowLevel;
+}
+
+
+
+extern btScalar gContactBreakingThreshold;
+
+
+//
+// Convex-Convex collision algorithm
+//
+void btConvex2dConvex2dAlgorithm ::processCollision (btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
+{
+
+	if (!m_manifoldPtr)
+	{
+		//swapped?
+		m_manifoldPtr = m_dispatcher->getNewManifold(body0,body1);
+		m_ownManifold = true;
+	}
+	resultOut->setPersistentManifold(m_manifoldPtr);
+
+	//comment-out next line to test multi-contact generation
+	//resultOut->getPersistentManifold()->clearManifold();
+
+
+	btConvexShape* min0 = static_cast<btConvexShape*>(body0->getCollisionShape());
+	btConvexShape* min1 = static_cast<btConvexShape*>(body1->getCollisionShape());
+
+	btVector3  normalOnB;
+	btVector3  pointOnBWorld;
+
+	{
+
+
+		btGjkPairDetector::ClosestPointInput input;
+
+		btGjkPairDetector	gjkPairDetector(min0,min1,m_simplexSolver,m_pdSolver);
+		//TODO: if (dispatchInfo.m_useContinuous)
+		gjkPairDetector.setMinkowskiA(min0);
+		gjkPairDetector.setMinkowskiB(min1);
+
+		{
+			input.m_maximumDistanceSquared = min0->getMargin() + min1->getMargin() + m_manifoldPtr->getContactBreakingThreshold();
+			input.m_maximumDistanceSquared*= input.m_maximumDistanceSquared;
+		}
+
+		input.m_stackAlloc = dispatchInfo.m_stackAllocator;
+		input.m_transformA = body0->getWorldTransform();
+		input.m_transformB = body1->getWorldTransform();
+
+		gjkPairDetector.getClosestPoints(input,*resultOut,dispatchInfo.m_debugDraw);
+
+		btVector3 v0,v1;
+		btVector3 sepNormalWorldSpace;
+
+	}
+
+	if (m_ownManifold)
+	{
+		resultOut->refreshContactPoints();
+	}
+
+}
+
+
+
+
+btScalar	btConvex2dConvex2dAlgorithm::calculateTimeOfImpact(btCollisionObject* col0,btCollisionObject* col1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
+{
+	(void)resultOut;
+	(void)dispatchInfo;
+	///Rather then checking ALL pairs, only calculate TOI when motion exceeds threshold
+
+	///Linear motion for one of objects needs to exceed m_ccdSquareMotionThreshold
+	///col0->m_worldTransform,
+	btScalar resultFraction = btScalar(1.);
+
+
+	btScalar squareMot0 = (col0->getInterpolationWorldTransform().getOrigin() - col0->getWorldTransform().getOrigin()).length2();
+	btScalar squareMot1 = (col1->getInterpolationWorldTransform().getOrigin() - col1->getWorldTransform().getOrigin()).length2();
+
+	if (squareMot0 < col0->getCcdSquareMotionThreshold() &&
+		squareMot1 < col1->getCcdSquareMotionThreshold())
+		return resultFraction;
+
+
+	//An adhoc way of testing the Continuous Collision Detection algorithms
+	//One object is approximated as a sphere, to simplify things
+	//Starting in penetration should report no time of impact
+	//For proper CCD, better accuracy and handling of 'allowed' penetration should be added
+	//also the mainloop of the physics should have a kind of toi queue (something like Brian Mirtich's application of Timewarp for Rigidbodies)
+
+
+	/// Convex0 against sphere for Convex1
+	{
+		btConvexShape* convex0 = static_cast<btConvexShape*>(col0->getCollisionShape());
+
+		btSphereShape	sphere1(col1->getCcdSweptSphereRadius()); //todo: allow non-zero sphere sizes, for better approximation
+		btConvexCast::CastResult result;
+		btVoronoiSimplexSolver voronoiSimplex;
+		//SubsimplexConvexCast ccd0(&sphere,min0,&voronoiSimplex);
+		///Simplification, one object is simplified as a sphere
+		btGjkConvexCast ccd1( convex0 ,&sphere1,&voronoiSimplex);
+		//ContinuousConvexCollision ccd(min0,min1,&voronoiSimplex,0);
+		if (ccd1.calcTimeOfImpact(col0->getWorldTransform(),col0->getInterpolationWorldTransform(),
+			col1->getWorldTransform(),col1->getInterpolationWorldTransform(),result))
+		{
+
+			//store result.m_fraction in both bodies
+
+			if (col0->getHitFraction()> result.m_fraction)
+				col0->setHitFraction( result.m_fraction );
+
+			if (col1->getHitFraction() > result.m_fraction)
+				col1->setHitFraction( result.m_fraction);
+
+			if (resultFraction > result.m_fraction)
+				resultFraction = result.m_fraction;
+
+		}
+
+
+
+
+	}
+
+	/// Sphere (for convex0) against Convex1
+	{
+		btConvexShape* convex1 = static_cast<btConvexShape*>(col1->getCollisionShape());
+
+		btSphereShape	sphere0(col0->getCcdSweptSphereRadius()); //todo: allow non-zero sphere sizes, for better approximation
+		btConvexCast::CastResult result;
+		btVoronoiSimplexSolver voronoiSimplex;
+		//SubsimplexConvexCast ccd0(&sphere,min0,&voronoiSimplex);
+		///Simplification, one object is simplified as a sphere
+		btGjkConvexCast ccd1(&sphere0,convex1,&voronoiSimplex);
+		//ContinuousConvexCollision ccd(min0,min1,&voronoiSimplex,0);
+		if (ccd1.calcTimeOfImpact(col0->getWorldTransform(),col0->getInterpolationWorldTransform(),
+			col1->getWorldTransform(),col1->getInterpolationWorldTransform(),result))
+		{
+
+			//store result.m_fraction in both bodies
+
+			if (col0->getHitFraction()	> result.m_fraction)
+				col0->setHitFraction( result.m_fraction);
+
+			if (col1->getHitFraction() > result.m_fraction)
+				col1->setHitFraction( result.m_fraction);
+
+			if (resultFraction > result.m_fraction)
+				resultFraction = result.m_fraction;
+
+		}
+	}
+
+	return resultFraction;
+
+}
+

src/BulletCollision/CollisionDispatch/btConvex2dConvex2dAlgorithm.h

@@ -0,0 +1,95 @@
+/*
+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 CONVEX_2D_CONVEX_2D_ALGORITHM_H
+#define CONVEX_2D_CONVEX_2D_ALGORITHM_H
+
+#include "BulletCollision/CollisionDispatch/btActivatingCollisionAlgorithm.h"
+#include "BulletCollision/NarrowPhaseCollision/btGjkPairDetector.h"
+#include "BulletCollision/NarrowPhaseCollision/btPersistentManifold.h"
+#include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h"
+#include "BulletCollision/NarrowPhaseCollision/btVoronoiSimplexSolver.h"
+#include "BulletCollision/CollisionDispatch/btCollisionCreateFunc.h"
+#include "BulletCollision/CollisionDispatch/btCollisionDispatcher.h"
+#include "LinearMath/btTransformUtil.h" //for btConvexSeparatingDistanceUtil
+
+class btConvexPenetrationDepthSolver;
+
+
+///The convex2dConvex2dAlgorithm collision algorithm support 2d collision detection for btConvex2dShape
+///Currently it requires the btMinkowskiPenetrationDepthSolver, it has support for 2d penetration depth computation
+class btConvex2dConvex2dAlgorithm : public btActivatingCollisionAlgorithm
+{
+	btSimplexSolverInterface*		m_simplexSolver;
+	btConvexPenetrationDepthSolver* m_pdSolver;
+
+	
+	bool	m_ownManifold;
+	btPersistentManifold*	m_manifoldPtr;
+	bool			m_lowLevelOfDetail;
+	
+	int m_numPerturbationIterations;
+	int m_minimumPointsPerturbationThreshold;
+
+public:
+
+	btConvex2dConvex2dAlgorithm(btPersistentManifold* mf,const btCollisionAlgorithmConstructionInfo& ci,btCollisionObject* body0,btCollisionObject* body1, btSimplexSolverInterface* simplexSolver, btConvexPenetrationDepthSolver* pdSolver, int numPerturbationIterations, int minimumPointsPerturbationThreshold);
+
+
+	virtual ~btConvex2dConvex2dAlgorithm();
+
+	virtual void processCollision (btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut);
+
+	virtual btScalar calculateTimeOfImpact(btCollisionObject* body0,btCollisionObject* body1,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut);
+
+	virtual	void	getAllContactManifolds(btManifoldArray&	manifoldArray)
+	{
+		///should we use m_ownManifold to avoid adding duplicates?
+		if (m_manifoldPtr && m_ownManifold)
+			manifoldArray.push_back(m_manifoldPtr);
+	}
+
+
+	void	setLowLevelOfDetail(bool useLowLevel);
+
+
+	const btPersistentManifold*	getManifold()
+	{
+		return m_manifoldPtr;
+	}
+
+	struct CreateFunc :public 	btCollisionAlgorithmCreateFunc
+	{
+
+		btConvexPenetrationDepthSolver*		m_pdSolver;
+		btSimplexSolverInterface*			m_simplexSolver;
+		int m_numPerturbationIterations;
+		int m_minimumPointsPerturbationThreshold;
+
+		CreateFunc(btSimplexSolverInterface*			simplexSolver, btConvexPenetrationDepthSolver* pdSolver);
+		
+		virtual ~CreateFunc();
+
+		virtual	btCollisionAlgorithm* CreateCollisionAlgorithm(btCollisionAlgorithmConstructionInfo& ci, btCollisionObject* body0,btCollisionObject* body1)
+		{
+			void* mem = ci.m_dispatcher1->allocateCollisionAlgorithm(sizeof(btConvex2dConvex2dAlgorithm));
+			return new(mem) btConvex2dConvex2dAlgorithm(ci.m_manifold,ci,body0,body1,m_simplexSolver,m_pdSolver,m_numPerturbationIterations,m_minimumPointsPerturbationThreshold);
+		}
+	};
+
+
+};
+
+#endif //CONVEX_2D_CONVEX_2D_ALGORITHM_H

src/BulletCollision/CollisionShapes/btBox2dShape.cpp

@@ -0,0 +1,42 @@
+/*
+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 "btBox2dShape.h"
+
+
+//{ 
+
+
+void btBox2dShape::getAabb(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax) const
+{
+	btTransformAabb(getHalfExtentsWithoutMargin(),getMargin(),t,aabbMin,aabbMax);
+}
+
+
+void	btBox2dShape::calculateLocalInertia(btScalar mass,btVector3& inertia) const
+{
+	//btScalar margin = btScalar(0.);
+	btVector3 halfExtents = getHalfExtentsWithMargin();
+
+	btScalar lx=btScalar(2.)*(halfExtents.x());
+	btScalar ly=btScalar(2.)*(halfExtents.y());
+	btScalar lz=btScalar(2.)*(halfExtents.z());
+
+	inertia.setValue(mass/(btScalar(12.0)) * (ly*ly + lz*lz),
+					mass/(btScalar(12.0)) * (lx*lx + lz*lz),
+					mass/(btScalar(12.0)) * (lx*lx + ly*ly));
+
+}
+

src/BulletCollision/CollisionShapes/btBox2dShape.h

@@ -0,0 +1,363 @@
+/*
+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 OBB_BOX_2D_SHAPE_H
+#define OBB_BOX_2D_SHAPE_H
+
+#include "BulletCollision/CollisionShapes/btPolyhedralConvexShape.h"
+#include "BulletCollision/CollisionShapes/btCollisionMargin.h"
+#include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h"
+#include "LinearMath/btVector3.h"
+#include "LinearMath/btMinMax.h"
+
+///The btBox2dShape is a box primitive around the origin, its sides axis aligned with length specified by half extents, in local shape coordinates. When used as part of a btCollisionObject or btRigidBody it will be an oriented box in world space.
+class btBox2dShape: public btPolyhedralConvexShape
+{
+
+	//btVector3	m_boxHalfExtents1; //use m_implicitShapeDimensions instead
+
+	btVector3 m_centroid;
+	btVector3 m_vertices[4];
+	btVector3 m_normals[4];
+
+public:
+
+	btVector3 getHalfExtentsWithMargin() const
+	{
+		btVector3 halfExtents = getHalfExtentsWithoutMargin();
+		btVector3 margin(getMargin(),getMargin(),getMargin());
+		halfExtents += margin;
+		return halfExtents;
+	}
+	
+	const btVector3& getHalfExtentsWithoutMargin() const
+	{
+		return m_implicitShapeDimensions;//changed in Bullet 2.63: assume the scaling and margin are included
+	}
+	
+
+	virtual btVector3	localGetSupportingVertex(const btVector3& vec) const
+	{
+		btVector3 halfExtents = getHalfExtentsWithoutMargin();
+		btVector3 margin(getMargin(),getMargin(),getMargin());
+		halfExtents += margin;
+		
+		return btVector3(btFsels(vec.x(), halfExtents.x(), -halfExtents.x()),
+			btFsels(vec.y(), halfExtents.y(), -halfExtents.y()),
+			btFsels(vec.z(), halfExtents.z(), -halfExtents.z()));
+	}
+
+	SIMD_FORCE_INLINE  btVector3	localGetSupportingVertexWithoutMargin(const btVector3& vec)const
+	{
+		const btVector3& halfExtents = getHalfExtentsWithoutMargin();
+		
+		return btVector3(btFsels(vec.x(), halfExtents.x(), -halfExtents.x()),
+			btFsels(vec.y(), halfExtents.y(), -halfExtents.y()),
+			btFsels(vec.z(), halfExtents.z(), -halfExtents.z()));
+	}
+
+	virtual void	batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const
+	{
+		const btVector3& halfExtents = getHalfExtentsWithoutMargin();
+	
+		for (int i=0;i<numVectors;i++)
+		{
+			const btVector3& vec = vectors[i];
+			supportVerticesOut[i].setValue(btFsels(vec.x(), halfExtents.x(), -halfExtents.x()),
+				btFsels(vec.y(), halfExtents.y(), -halfExtents.y()),
+				btFsels(vec.z(), halfExtents.z(), -halfExtents.z())); 
+		}
+
+	}
+
+
+	btBox2dShape( const btVector3& boxHalfExtents) 
+		: btPolyhedralConvexShape(),
+		m_centroid(0,0,0)
+	{
+		m_vertices[0].setValue(-boxHalfExtents.getX(),-boxHalfExtents.getY(),0);
+		m_vertices[1].setValue(boxHalfExtents.getX(),-boxHalfExtents.getY(),0);
+		m_vertices[2].setValue(boxHalfExtents.getX(),boxHalfExtents.getY(),0);
+		m_vertices[3].setValue(-boxHalfExtents.getX(),boxHalfExtents.getY(),0);
+
+		m_normals[0].setValue(0,-1,0);
+		m_normals[1].setValue(1,0,0);
+		m_normals[2].setValue(0,1,0);
+		m_normals[3].setValue(-1,0,0);
+
+		m_shapeType = BOX_2D_SHAPE_PROXYTYPE;
+		btVector3 margin(getMargin(),getMargin(),getMargin());
+		m_implicitShapeDimensions = (boxHalfExtents * m_localScaling) - margin;
+	};
+
+	virtual void setMargin(btScalar collisionMargin)
+	{
+		//correct the m_implicitShapeDimensions for the margin
+		btVector3 oldMargin(getMargin(),getMargin(),getMargin());
+		btVector3 implicitShapeDimensionsWithMargin = m_implicitShapeDimensions+oldMargin;
+		
+		btConvexInternalShape::setMargin(collisionMargin);
+		btVector3 newMargin(getMargin(),getMargin(),getMargin());
+		m_implicitShapeDimensions = implicitShapeDimensionsWithMargin - newMargin;
+
+	}
+	virtual void	setLocalScaling(const btVector3& scaling)
+	{
+		btVector3 oldMargin(getMargin(),getMargin(),getMargin());
+		btVector3 implicitShapeDimensionsWithMargin = m_implicitShapeDimensions+oldMargin;
+		btVector3 unScaledImplicitShapeDimensionsWithMargin = implicitShapeDimensionsWithMargin / m_localScaling;
+
+		btConvexInternalShape::setLocalScaling(scaling);
+
+		m_implicitShapeDimensions = (unScaledImplicitShapeDimensionsWithMargin * m_localScaling) - oldMargin;
+
+	}
+
+	virtual void getAabb(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax) const;
+
+	
+
+	virtual void	calculateLocalInertia(btScalar mass,btVector3& inertia) const;
+
+
+
+
+
+	int	getVertexCount() const
+	{
+		return 4;
+	}
+
+	virtual int getNumVertices()const
+	{
+		return 4;
+	}
+
+	const btVector3* getVertices() const
+	{
+		return &m_vertices[0];
+	}
+
+	const btVector3* getNormals() const
+	{
+		return &m_normals[0];
+	}
+
+
+
+
+
+
+
+	virtual void getPlane(btVector3& planeNormal,btVector3& planeSupport,int i ) const
+	{
+		//this plane might not be aligned...
+		btVector4 plane ;
+		getPlaneEquation(plane,i);
+		planeNormal = btVector3(plane.getX(),plane.getY(),plane.getZ());
+		planeSupport = localGetSupportingVertex(-planeNormal);
+	}
+
+
+	const btVector3& getCentroid() const
+	{
+		return m_centroid;
+	}
+	
+	virtual int getNumPlanes() const
+	{
+		return 6;
+	}	
+	
+	
+
+	virtual int getNumEdges() const
+	{
+		return 12;
+	}
+
+
+	virtual void getVertex(int i,btVector3& vtx) const
+	{
+		btVector3 halfExtents = getHalfExtentsWithoutMargin();
+
+		vtx = btVector3(
+				halfExtents.x() * (1-(i&1)) - halfExtents.x() * (i&1),
+				halfExtents.y() * (1-((i&2)>>1)) - halfExtents.y() * ((i&2)>>1),
+				halfExtents.z() * (1-((i&4)>>2)) - halfExtents.z() * ((i&4)>>2));
+	}
+	
+
+	virtual void	getPlaneEquation(btVector4& plane,int i) const
+	{
+		btVector3 halfExtents = getHalfExtentsWithoutMargin();
+
+		switch (i)
+		{
+		case 0:
+			plane.setValue(btScalar(1.),btScalar(0.),btScalar(0.),-halfExtents.x());
+			break;
+		case 1:
+			plane.setValue(btScalar(-1.),btScalar(0.),btScalar(0.),-halfExtents.x());
+			break;
+		case 2:
+			plane.setValue(btScalar(0.),btScalar(1.),btScalar(0.),-halfExtents.y());
+			break;
+		case 3:
+			plane.setValue(btScalar(0.),btScalar(-1.),btScalar(0.),-halfExtents.y());
+			break;
+		case 4:
+			plane.setValue(btScalar(0.),btScalar(0.),btScalar(1.),-halfExtents.z());
+			break;
+		case 5:
+			plane.setValue(btScalar(0.),btScalar(0.),btScalar(-1.),-halfExtents.z());
+			break;
+		default:
+			btAssert(0);
+		}
+	}
+
+	
+	virtual void getEdge(int i,btVector3& pa,btVector3& pb) const
+	//virtual void getEdge(int i,Edge& edge) const
+	{
+		int edgeVert0 = 0;
+		int edgeVert1 = 0;
+
+		switch (i)
+		{
+		case 0:
+				edgeVert0 = 0;
+				edgeVert1 = 1;
+			break;
+		case 1:
+				edgeVert0 = 0;
+				edgeVert1 = 2;
+			break;
+		case 2:
+			edgeVert0 = 1;
+			edgeVert1 = 3;
+
+			break;
+		case 3:
+			edgeVert0 = 2;
+			edgeVert1 = 3;
+			break;
+		case 4:
+			edgeVert0 = 0;
+			edgeVert1 = 4;
+			break;
+		case 5:
+			edgeVert0 = 1;
+			edgeVert1 = 5;
+
+			break;
+		case 6:
+			edgeVert0 = 2;
+			edgeVert1 = 6;
+			break;
+		case 7:
+			edgeVert0 = 3;
+			edgeVert1 = 7;
+			break;
+		case 8:
+			edgeVert0 = 4;
+			edgeVert1 = 5;
+			break;
+		case 9:
+			edgeVert0 = 4;
+			edgeVert1 = 6;
+			break;
+		case 10:
+			edgeVert0 = 5;
+			edgeVert1 = 7;
+			break;
+		case 11:
+			edgeVert0 = 6;
+			edgeVert1 = 7;
+			break;
+		default:
+			btAssert(0);
+
+		}
+
+		getVertex(edgeVert0,pa );
+		getVertex(edgeVert1,pb );
+	}
+
+
+
+
+	
+	virtual	bool isInside(const btVector3& pt,btScalar tolerance) const
+	{
+		btVector3 halfExtents = getHalfExtentsWithoutMargin();
+
+		//btScalar minDist = 2*tolerance;
+		
+		bool result =	(pt.x() <= (halfExtents.x()+tolerance)) &&
+						(pt.x() >= (-halfExtents.x()-tolerance)) &&
+						(pt.y() <= (halfExtents.y()+tolerance)) &&
+						(pt.y() >= (-halfExtents.y()-tolerance)) &&
+						(pt.z() <= (halfExtents.z()+tolerance)) &&
+						(pt.z() >= (-halfExtents.z()-tolerance));
+		
+		return result;
+	}
+
+
+	//debugging
+	virtual const char*	getName()const
+	{
+		return "Box2d";
+	}
+
+	virtual int		getNumPreferredPenetrationDirections() const
+	{
+		return 6;
+	}
+	
+	virtual void	getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const
+	{
+		switch (index)
+		{
+		case 0:
+			penetrationVector.setValue(btScalar(1.),btScalar(0.),btScalar(0.));
+			break;
+		case 1:
+			penetrationVector.setValue(btScalar(-1.),btScalar(0.),btScalar(0.));
+			break;
+		case 2:
+			penetrationVector.setValue(btScalar(0.),btScalar(1.),btScalar(0.));
+			break;
+		case 3:
+			penetrationVector.setValue(btScalar(0.),btScalar(-1.),btScalar(0.));
+			break;
+		case 4:
+			penetrationVector.setValue(btScalar(0.),btScalar(0.),btScalar(1.));
+			break;
+		case 5:
+			penetrationVector.setValue(btScalar(0.),btScalar(0.),btScalar(-1.));
+			break;
+		default:
+			btAssert(0);
+		}
+	}
+
+};
+
+#endif //OBB_BOX_2D_SHAPE_H
+
+

src/BulletCollision/CollisionShapes/btCollisionShape.h

@@ -60,6 +60,11 @@ public:
 		return btBroadphaseProxy::isPolyhedral(getShapeType());
 	}
 
+	SIMD_FORCE_INLINE bool	isConvex2d() const
+	{
+		return btBroadphaseProxy::isConvex2d(getShapeType());
+	}
+
 	SIMD_FORCE_INLINE bool	isConvex() const
 	{
 		return btBroadphaseProxy::isConvex(getShapeType());

src/BulletCollision/CollisionShapes/btConvex2dShape.cpp

@@ -0,0 +1,92 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2009 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 "btConvex2dShape.h"
+
+btConvex2dShape::btConvex2dShape(	btConvexShape* convexChildShape):
+btConvexShape (), m_childConvexShape(convexChildShape)
+{
+	m_shapeType = CONVEX_2D_SHAPE_PROXYTYPE;
+}
+	
+btConvex2dShape::~btConvex2dShape()
+{
+}
+
+	
+
+btVector3	btConvex2dShape::localGetSupportingVertexWithoutMargin(const btVector3& vec)const
+{
+	return m_childConvexShape->localGetSupportingVertexWithoutMargin(vec);
+}
+
+void	btConvex2dShape::batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const
+{
+	m_childConvexShape->batchedUnitVectorGetSupportingVertexWithoutMargin(vectors,supportVerticesOut,numVectors);
+}
+
+
+btVector3	btConvex2dShape::localGetSupportingVertex(const btVector3& vec)const
+{
+	return m_childConvexShape->localGetSupportingVertex(vec);
+}
+
+
+void	btConvex2dShape::calculateLocalInertia(btScalar mass,btVector3& inertia) const
+{
+	///this linear upscaling is not realistic, but we don't deal with large mass ratios...
+	m_childConvexShape->calculateLocalInertia(mass,inertia);
+}
+
+
+	///getAabb's default implementation is brute force, expected derived classes to implement a fast dedicated version
+void btConvex2dShape::getAabb(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax) const
+{
+	m_childConvexShape->getAabb(t,aabbMin,aabbMax);
+}
+
+void btConvex2dShape::getAabbSlow(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax) const
+{
+	m_childConvexShape->getAabbSlow(t,aabbMin,aabbMax);
+}
+
+void	btConvex2dShape::setLocalScaling(const btVector3& scaling) 
+{
+	m_childConvexShape->setLocalScaling(scaling);
+}
+
+const btVector3& btConvex2dShape::getLocalScaling() const
+{
+	return m_childConvexShape->getLocalScaling();
+}
+
+void	btConvex2dShape::setMargin(btScalar margin)
+{
+	m_childConvexShape->setMargin(margin);
+}
+btScalar	btConvex2dShape::getMargin() const
+{
+	return m_childConvexShape->getMargin();
+}
+
+int		btConvex2dShape::getNumPreferredPenetrationDirections() const
+{
+	return m_childConvexShape->getNumPreferredPenetrationDirections();
+}
+	
+void	btConvex2dShape::getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const
+{
+	m_childConvexShape->getPreferredPenetrationDirection(index,penetrationVector);
+}

src/BulletCollision/CollisionShapes/btConvex2dShape.h

@@ -0,0 +1,80 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2009 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_CONVEX_2D_SHAPE_H
+#define BT_CONVEX_2D_SHAPE_H
+
+#include "BulletCollision/CollisionShapes/btConvexShape.h"
+#include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h" // for the types
+
+///The btConvex2dShape allows to use arbitrary convex shapes are 2d convex shapes, with the Z component assumed to be 0.
+///For 2d boxes, the btBox2dShape is recommended.
+class btConvex2dShape : public btConvexShape
+{
+	btConvexShape*	m_childConvexShape;
+
+	public:
+	
+	btConvex2dShape(	btConvexShape* convexChildShape);
+	
+	virtual ~btConvex2dShape();
+	
+	virtual btVector3	localGetSupportingVertexWithoutMargin(const btVector3& vec)const;
+
+	virtual btVector3	localGetSupportingVertex(const btVector3& vec)const;
+
+	virtual void	batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const;
+
+	virtual void	calculateLocalInertia(btScalar mass,btVector3& inertia) const;
+
+	btConvexShape*	getChildShape() 
+	{
+		return m_childConvexShape;
+	}
+
+	const btConvexShape*	getChildShape() const
+	{
+		return m_childConvexShape;
+	}
+
+	virtual const char*	getName()const 
+	{
+		return "Convex2dShape";
+	}
+	
+
+
+	///////////////////////////
+
+
+	///getAabb's default implementation is brute force, expected derived classes to implement a fast dedicated version
+	void getAabb(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax) const;
+
+	virtual void getAabbSlow(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax) const;
+
+	virtual void	setLocalScaling(const btVector3& scaling) ;
+	virtual const btVector3& getLocalScaling() const ;
+
+	virtual void	setMargin(btScalar margin);
+	virtual btScalar	getMargin() const;
+
+	virtual int		getNumPreferredPenetrationDirections() const;
+	
+	virtual void	getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const;
+
+
+};
+
+#endif //BT_CONVEX_2D_SHAPE_H

src/BulletCollision/NarrowPhaseCollision/btGjkPairDetector.cpp

@@ -39,7 +39,8 @@ int gNumGjkChecks = 0;
 
 
 btGjkPairDetector::btGjkPairDetector(const btConvexShape* objectA,const btConvexShape* objectB,btSimplexSolverInterface* simplexSolver,btConvexPenetrationDepthSolver*	penetrationDepthSolver)
-:m_penetrationDepthSolver(penetrationDepthSolver),
+:m_cachedSeparatingAxis(btScalar(0.),btScalar(1.),btScalar(0.)),
+m_penetrationDepthSolver(penetrationDepthSolver),
 m_simplexSolver(simplexSolver),
 m_minkowskiA(objectA),
 m_minkowskiB(objectB),
@@ -53,7 +54,7 @@ m_catchDegeneracies(1)
 {
 }
 btGjkPairDetector::btGjkPairDetector(const btConvexShape* objectA,const btConvexShape* objectB,int shapeTypeA,int shapeTypeB,btScalar marginA, btScalar marginB, btSimplexSolverInterface* simplexSolver,btConvexPenetrationDepthSolver*	penetrationDepthSolver)
-:m_cachedSeparatingAxis(btScalar(0.),btScalar(0.),btScalar(1.)),
+:m_cachedSeparatingAxis(btScalar(0.),btScalar(1.),btScalar(0.)),
 m_penetrationDepthSolver(penetrationDepthSolver),
 m_simplexSolver(simplexSolver),
 m_minkowskiA(objectA),
@@ -92,6 +93,7 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 	localTransA.getOrigin() -= positionOffset;
 	localTransB.getOrigin() -= positionOffset;
 
+	bool check2d = m_minkowskiA->isConvex2d() && m_minkowskiB->isConvex2d();
 
 	btScalar marginA = m_marginA;
 	btScalar marginB = m_marginB;
@@ -171,12 +173,19 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 		spu_printf("got local supporting vertices\n");
 #endif
 
+			if (check2d)
+			{
+				pWorld[2] = 0.f;
+				qWorld[2] = 0.f;
+			}
+
 			btVector3 w	= pWorld - qWorld;
 			delta = m_cachedSeparatingAxis.dot(w);
 
 			// potential exit, they don't overlap
 			if ((delta > btScalar(0.0)) && (delta * delta > squaredDistance * input.m_maximumDistanceSquared)) 
 			{
+				m_degenerateSimplex = 10;
 				checkSimplex=true;
 				//checkPenetration = false;
 				break;
@@ -198,6 +207,9 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 				if (f0 <= btScalar(0.))
 				{
 					m_degenerateSimplex = 2;
+				} else
+				{
+					m_degenerateSimplex = 11;
 				}
 				checkSimplex = true;
 				break;
@@ -231,6 +243,8 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 
 			btScalar previousSquaredDistance = squaredDistance;
 			squaredDistance = newCachedSeparatingAxis.length2();
+#if 0
+///warning: this termination condition leads to some problems in 2d test case see Bullet/Demos/Box2dDemo
 			if (squaredDistance>previousSquaredDistance)
 			{
 				m_degenerateSimplex = 7;
@@ -238,6 +252,7 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
                 checkSimplex = false;
                 break;
 			}
+#endif //
 			
 			m_cachedSeparatingAxis = newCachedSeparatingAxis;
 
@@ -248,6 +263,8 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 			{ 
 				m_simplexSolver->backup_closest(m_cachedSeparatingAxis);
 				checkSimplex = true;
+				m_degenerateSimplex = 12;
+				
 				break;
 			}
 
@@ -278,6 +295,7 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 			{
 				//do we need this backup_closest here ?
 				m_simplexSolver->backup_closest(m_cachedSeparatingAxis);
+				m_degenerateSimplex = 13;
 				break;
 			}
 		}
@@ -286,7 +304,8 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 		{
 			m_simplexSolver->compute_points(pointOnA, pointOnB);
 			normalInB = pointOnA-pointOnB;
-			btScalar lenSqr = m_cachedSeparatingAxis.length2();
+			btScalar lenSqr =m_cachedSeparatingAxis.length2();
+			
 			//valid normal
 			if (lenSqr < 0.0001)
 			{
@@ -390,6 +409,7 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 							pointOnA -= m_cachedSeparatingAxis * marginA ;
 							pointOnB += m_cachedSeparatingAxis * marginB ;
 							normalInB = m_cachedSeparatingAxis;
+							normalInB.normalize();
 							isValid = true;
 							m_lastUsedMethod = 6;
 						} else
@@ -404,16 +424,19 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 		}
 	}
 
-	if (isValid)
+	
+
+	if (isValid && ((distance < 0) || (distance*distance < input.m_maximumDistanceSquared)))
 	{
-#ifdef __SPU__
-		//spu_printf("distance\n");
-#endif //__CELLOS_LV2__
+#if 0
+///some debugging
+//		if (check2d)
+		{
+			printf("n = %2.3f,%2.3f,%2.3f. ",normalInB[0],normalInB[1],normalInB[2]);
+			printf("distance = %2.3f exit=%d deg=%d\n",distance,m_lastUsedMethod,m_degenerateSimplex);
+		}
+#endif 
 
-
-#ifdef DEBUG_SPU_COLLISION_DETECTION
-		spu_printf("output 1\n");
-#endif
 		m_cachedSeparatingAxis = normalInB;
 		m_cachedSeparatingDistance = distance;
 
@@ -422,10 +445,6 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 			pointOnB+positionOffset,
 			distance);
 
-#ifdef DEBUG_SPU_COLLISION_DETECTION
-		spu_printf("output 2\n");
-#endif
-		//printf("gjk add:%f",distance);
 	}
 
 

src/BulletCollision/NarrowPhaseCollision/btMinkowskiPenetrationDepthSolver.cpp

@@ -78,6 +78,7 @@ bool btMinkowskiPenetrationDepthSolver::calcPenDepth(btSimplexSolverInterface& s
 	(void)stackAlloc;
 	(void)v;
 	
+	bool check2d= convexA->isConvex2d() && convexB->isConvex2d();
 
 	struct btIntermediateResult : public btDiscreteCollisionDetectorInterface::Result
 	{
@@ -132,7 +133,7 @@ bool btMinkowskiPenetrationDepthSolver::calcPenDepth(btSimplexSolverInterface& s
 
 	for (i=0;i<numSampleDirections;i++)
 	{
-		const btVector3& norm = sPenetrationDirections[i];
+		btVector3 norm = sPenetrationDirections[i];
 		seperatingAxisInABatch[i] =  (-norm) * transA.getBasis() ;
 		seperatingAxisInBBatch[i] =  norm   * transB.getBasis() ;
 	}
@@ -173,29 +174,44 @@ bool btMinkowskiPenetrationDepthSolver::calcPenDepth(btSimplexSolverInterface& s
 
 
 
+
 	convexA->batchedUnitVectorGetSupportingVertexWithoutMargin(seperatingAxisInABatch,supportVerticesABatch,numSampleDirections);
 	convexB->batchedUnitVectorGetSupportingVertexWithoutMargin(seperatingAxisInBBatch,supportVerticesBBatch,numSampleDirections);
 
 	for (i=0;i<numSampleDirections;i++)
 	{
-		const btVector3& norm = sPenetrationDirections[i];
-		seperatingAxisInA = seperatingAxisInABatch[i];
-		seperatingAxisInB = seperatingAxisInBBatch[i];
-
-		pInA = supportVerticesABatch[i];
-		qInB = supportVerticesBBatch[i];
-
-		pWorld = transA(pInA);	
-		qWorld = transB(qInB);
-		w	= qWorld - pWorld;
-		btScalar delta = norm.dot(w);
-		//find smallest delta
-		if (delta < minProj)
+		btVector3 norm = sPenetrationDirections[i];
+		if (check2d)
 		{
-			minProj = delta;
-			minNorm = norm;
-			minA = pWorld;
-			minB = qWorld;
+			norm[2] = 0.f;
+		}
+		if (norm.length2()>0.01)
+		{
+
+			seperatingAxisInA = seperatingAxisInABatch[i];
+			seperatingAxisInB = seperatingAxisInBBatch[i];
+
+			pInA = supportVerticesABatch[i];
+			qInB = supportVerticesBBatch[i];
+
+			pWorld = transA(pInA);	
+			qWorld = transB(qInB);
+			if (check2d)
+			{
+				pWorld[2] = 0.f;
+				qWorld[2] = 0.f;
+			}
+
+			w	= qWorld - pWorld;
+			btScalar delta = norm.dot(w);
+			//find smallest delta
+			if (delta < minProj)
+			{
+				minProj = delta;
+				minNorm = norm;
+				minA = pWorld;
+				minB = qWorld;
+			}
 		}
 	}	
 #else
@@ -264,7 +280,8 @@ bool btMinkowskiPenetrationDepthSolver::calcPenDepth(btSimplexSolverInterface& s
 	if (minProj < btScalar(0.))
 		return false;
 
-	minProj += (convexA->getMarginNonVirtual() + convexB->getMarginNonVirtual());
+	btScalar extraSeparation = 0.5f;///scale dependent
+	minProj += extraSeparation+(convexA->getMarginNonVirtual() + convexB->getMarginNonVirtual());
 
 
 
@@ -305,6 +322,7 @@ bool btMinkowskiPenetrationDepthSolver::calcPenDepth(btSimplexSolverInterface& s
 	input.m_maximumDistanceSquared = btScalar(BT_LARGE_FLOAT);//minProj;
 	
 	btIntermediateResult res;
+	gjkdet.setCachedSeperatingAxis(-minNorm);
 	gjkdet.getClosestPoints(input,res,debugDraw);
 
 	btScalar correctedMinNorm = minProj - res.m_depth;
@@ -313,12 +331,14 @@ bool btMinkowskiPenetrationDepthSolver::calcPenDepth(btSimplexSolverInterface& s
 	//the penetration depth is over-estimated, relax it
 	btScalar penetration_relaxation= btScalar(1.);
 	minNorm*=penetration_relaxation;
+	
 
 	if (res.m_hasResult)
 	{
 
 		pa = res.m_pointInWorld - minNorm * correctedMinNorm;
 		pb = res.m_pointInWorld;
+		v = minNorm;
 		
 #ifdef DEBUG_DRAW
 		if (debugDraw)

src/LinearMath/btHashMap.h

@@ -171,8 +171,8 @@ class btHashMap
 
 			for(i=0;i<curHashtableSize;i++)
 			{
-				const Value& value = m_valueArray[i];
-				const Key& key = m_keyArray[i];
+				//const Value& value = m_valueArray[i];
+				//const Key& key = m_keyArray[i];
 
 				int	hashValue = m_keyArray[i].getHash() & (m_valueArray.capacity()-1);	// New hash value with new mask
 				m_next[i] = m_hashTable[hashValue];