diff --git a/Demos/ConcaveDemo/ConcavePhysicsDemo.cpp b/Demos/ConcaveDemo/ConcavePhysicsDemo.cpp
index d8e13758c..007d7fa1f 100644
--- a/Demos/ConcaveDemo/ConcavePhysicsDemo.cpp
+++ b/Demos/ConcaveDemo/ConcavePhysicsDemo.cpp
@@ -121,7 +121,10 @@ void	ConcaveDemo::initPhysics()
 	{
 		for (int j=0;j<NUM_VERTS_Y;j++)
 		{
-			gVertices[i+j*NUM_VERTS_X].setValue((i-NUM_VERTS_X*0.5f)*TRIANGLE_SIZE,2.f*sinf((float)i)*cosf((float)j),(j-NUM_VERTS_Y*0.5f)*TRIANGLE_SIZE);
+			gVertices[i+j*NUM_VERTS_X].setValue((i-NUM_VERTS_X*0.5f)*TRIANGLE_SIZE,
+				//0.f,
+				2.f*sinf((float)i)*cosf((float)j),
+				(j-NUM_VERTS_Y*0.5f)*TRIANGLE_SIZE);
 		}
 	}
 
@@ -156,7 +159,7 @@ void	ConcaveDemo::initPhysics()
 	float mass = 0.f;
 	btTransform	startTransform;
 	startTransform.setIdentity();
-	startTransform.setOrigin(btVector3(0,0,0));
+	startTransform.setOrigin(btVector3(0,-2,0));
 
 	btRigidBody* staticBody = localCreateRigidBody(mass, startTransform,trimeshShape);
 
diff --git a/Demos/OpenGL/GL_ShapeDrawer.cpp b/Demos/OpenGL/GL_ShapeDrawer.cpp
index 03b9e50e3..30b633611 100644
--- a/Demos/OpenGL/GL_ShapeDrawer.cpp
+++ b/Demos/OpenGL/GL_ShapeDrawer.cpp
@@ -65,22 +65,43 @@ void GL_ShapeDrawer::drawCoordSystem()  {
 
 class GlDrawcallback : public btTriangleCallback
 {
+
 public:
 
+	bool	m_wireframe;
+
+	GlDrawcallback()
+		:m_wireframe(false)
+	{
+	}
+
 	virtual void processTriangle(btVector3* triangle,int partId, int triangleIndex)
 	{
-		glBegin(GL_LINES);
-		glColor3f(1, 0, 0);
-		glVertex3d(triangle[0].getX(), triangle[0].getY(), triangle[0].getZ());
-		glVertex3d(triangle[1].getX(), triangle[1].getY(), triangle[1].getZ());
-		glColor3f(0, 1, 0);
-		glVertex3d(triangle[2].getX(), triangle[2].getY(), triangle[2].getZ());
-		glVertex3d(triangle[1].getX(), triangle[1].getY(), triangle[1].getZ());
-		glColor3f(0, 0, 1);
-		glVertex3d(triangle[2].getX(), triangle[2].getY(), triangle[2].getZ());
-		glVertex3d(triangle[0].getX(), triangle[0].getY(), triangle[0].getZ());
-		glEnd();
 
+		if (m_wireframe)
+		{
+			glBegin(GL_LINES);
+			glColor3f(1, 0, 0);
+			glVertex3d(triangle[0].getX(), triangle[0].getY(), triangle[0].getZ());
+			glVertex3d(triangle[1].getX(), triangle[1].getY(), triangle[1].getZ());
+			glColor3f(0, 1, 0);
+			glVertex3d(triangle[2].getX(), triangle[2].getY(), triangle[2].getZ());
+			glVertex3d(triangle[1].getX(), triangle[1].getY(), triangle[1].getZ());
+			glColor3f(0, 0, 1);
+			glVertex3d(triangle[2].getX(), triangle[2].getY(), triangle[2].getZ());
+			glVertex3d(triangle[0].getX(), triangle[0].getY(), triangle[0].getZ());
+			glEnd();
+		} else
+		{
+			glBegin(GL_TRIANGLES);
+			glColor3f(1, 0, 0);
+			glVertex3d(triangle[0].getX(), triangle[0].getY(), triangle[0].getZ());
+			glColor3f(0, 1, 0);
+			glVertex3d(triangle[1].getX(), triangle[1].getY(), triangle[1].getZ());
+			glColor3f(0, 0, 1);
+			glVertex3d(triangle[2].getX(), triangle[2].getY(), triangle[2].getZ());
+			glEnd();
+		}
 	}
 };
 
@@ -312,6 +333,7 @@ void GL_ShapeDrawer::drawOpenGL(float* m, const btCollisionShape* shape, const b
 			btVector3 aabbMin(-1e30f,-1e30f,-1e30f);
 
 			GlDrawcallback drawCallback;
+			drawCallback.m_wireframe = (debugMode & btIDebugDraw::DBG_DrawWireframe)!=0;
 
 			concaveMesh->processAllTriangles(&drawCallback,aabbMin,aabbMax);
 
diff --git a/Extras/ExtraSolid35/Solid3EpaPenetrationDepth.cpp b/Extras/ExtraSolid35/Solid3EpaPenetrationDepth.cpp
index 52723d85a..80b001af9 100644
--- a/Extras/ExtraSolid35/Solid3EpaPenetrationDepth.cpp
+++ b/Extras/ExtraSolid35/Solid3EpaPenetrationDepth.cpp
@@ -318,9 +318,11 @@ inline bool originInTetrahedron(const btVector3& p1, const btVector3& p2,
 
 
 bool Solid3EpaPenetrationDepth::calcPenDepth( btSimplexSolverInterface& simplexSolver,
-			btConvexShape* convexA,btConvexShape* convexB,
-			const btTransform& transformA,const btTransform& transformB,
-			btVector3& v, btPoint3& pa, btPoint3& pb)
+		btConvexShape* convexA,btConvexShape* convexB,
+					const btTransform& transformA,const btTransform& transformB,
+				btVector3& v, btPoint3& pa, btPoint3& pb,
+				class btIDebugDraw* debugDraw
+				)
 {
 	
     int num_verts = simplexSolver.getSimplex(pBuf, qBuf, yBuf);
diff --git a/Extras/ExtraSolid35/Solid3EpaPenetrationDepth.h b/Extras/ExtraSolid35/Solid3EpaPenetrationDepth.h
index d1757202f..501beac27 100644
--- a/Extras/ExtraSolid35/Solid3EpaPenetrationDepth.h
+++ b/Extras/ExtraSolid35/Solid3EpaPenetrationDepth.h
@@ -32,10 +32,12 @@ class Solid3EpaPenetrationDepth : public btConvexPenetrationDepthSolver
 {
 public:
 
-	virtual bool calcPenDepth(btSimplexSolverInterface& simplexSolver,
+		virtual bool calcPenDepth( btSimplexSolverInterface& simplexSolver,
 		btConvexShape* convexA,btConvexShape* convexB,
-		const btTransform& transformA,const btTransform& transformB,
-				btVector3& v, btPoint3& pa, btPoint3& pb);
+					const btTransform& transA,const btTransform& transB,
+				btVector3& v, btPoint3& pa, btPoint3& pb,
+				class btIDebugDraw* debugDraw
+				);
 
 };
 
diff --git a/VERSION b/VERSION
index afbce2d01..b49971824 100644
--- a/VERSION
+++ b/VERSION
@@ -1,3 +1,3 @@
-Bullet Collision Detection and Physics Library version 2.20
+Bullet Collision Detection and Physics Library version 2.22
 http://bullet.sourceforge.net
 
diff --git a/src/BulletCollision/CollisionShapes/btBoxShape.h b/src/BulletCollision/CollisionShapes/btBoxShape.h
index b137eb115..e85a36c0b 100644
--- a/src/BulletCollision/CollisionShapes/btBoxShape.h
+++ b/src/BulletCollision/CollisionShapes/btBoxShape.h
@@ -255,6 +255,37 @@ public:
 		return "Box";
 	}
 
+	virtual int		getNumPreferredPenetrationDirections() const
+	{
+		return 6;
+	}
+	
+	virtual void	getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const
+	{
+		switch (index)
+		{
+		case 0:
+			penetrationVector.setValue(1.f,0.f,0.f);
+			break;
+		case 1:
+			penetrationVector.setValue(-1.f,0.f,0.f);
+			break;
+		case 2:
+			penetrationVector.setValue(0.f,1.f,0.f);
+			break;
+		case 3:
+			penetrationVector.setValue(0.f,-1.f,0.f);
+			break;
+		case 4:
+			penetrationVector.setValue(0.f,0.f,1.f);
+			break;
+		case 5:
+			penetrationVector.setValue(0.f,0.f,-1.f);
+			break;
+		default:
+			assert(0);
+		}
+	}
 
 };
 
diff --git a/src/BulletCollision/CollisionShapes/btConvexShape.h b/src/BulletCollision/CollisionShapes/btConvexShape.h
index 3ffde1ba5..0de334b35 100644
--- a/src/BulletCollision/CollisionShapes/btConvexShape.h
+++ b/src/BulletCollision/CollisionShapes/btConvexShape.h
@@ -26,7 +26,7 @@ subject to the following restrictions:
 
 //todo: get rid of this btConvexCastResult thing!
 struct btConvexCastResult;
-
+#define MAX_PREFERRED_PENETRATION_DIRECTIONS 10
 
 /// btConvexShape is an abstract shape interface.
 /// The explicit part provides plane-equations, the implicit part provides GetClosestPoint interface.
@@ -84,6 +84,17 @@ public:
 		return m_collisionMargin;
 	}
 
+	virtual int		getNumPreferredPenetrationDirections() const
+	{
+		return 0;
+	}
+	
+	virtual void	getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const
+	{
+		assert(0);
+	}
+
+
 
 };
 
diff --git a/src/BulletCollision/CollisionShapes/btTriangleShape.h b/src/BulletCollision/CollisionShapes/btTriangleShape.h
index 8f0a06f75..8e6e2daa4 100644
--- a/src/BulletCollision/CollisionShapes/btTriangleShape.h
+++ b/src/BulletCollision/CollisionShapes/btTriangleShape.h
@@ -157,6 +157,18 @@ public:
 			return "Triangle";
 		}
 
+		virtual int		getNumPreferredPenetrationDirections() const
+		{
+			return 2;
+		}
+		
+		virtual void	getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const
+		{
+			calcNormal(penetrationVector);
+			if (index)
+				penetrationVector *= -1.f;
+		}
+
 
 };
 
diff --git a/src/BulletCollision/NarrowPhaseCollision/btMinkowskiPenetrationDepthSolver.cpp b/src/BulletCollision/NarrowPhaseCollision/btMinkowskiPenetrationDepthSolver.cpp
index 34daacf26..6b2112ef3 100644
--- a/src/BulletCollision/NarrowPhaseCollision/btMinkowskiPenetrationDepthSolver.cpp
+++ b/src/BulletCollision/NarrowPhaseCollision/btMinkowskiPenetrationDepthSolver.cpp
@@ -45,7 +45,7 @@ struct MyResult : public btDiscreteCollisionDetectorInterface::Result
 };
 
 #define NUM_UNITSPHERE_POINTS 42
-static btVector3	sPenetrationDirections[NUM_UNITSPHERE_POINTS] = 
+static btVector3	sPenetrationDirections[NUM_UNITSPHERE_POINTS+MAX_PREFERRED_PENETRATION_DIRECTIONS*2] = 
 {
 btVector3(0.000000f , -0.000000f,-1.000000f),
 btVector3(0.723608f , -0.525725f,-0.447219f),
@@ -110,22 +110,62 @@ bool btMinkowskiPenetrationDepthSolver::calcPenDepth(btSimplexSolverInterface& s
 
 #define USE_BATCHED_SUPPORT 1
 #ifdef USE_BATCHED_SUPPORT
-	btVector3	supportVerticesABatch[NUM_UNITSPHERE_POINTS];
-	btVector3	supportVerticesBBatch[NUM_UNITSPHERE_POINTS];
-	btVector3	seperatingAxisInABatch[NUM_UNITSPHERE_POINTS];
-	btVector3	seperatingAxisInBBatch[NUM_UNITSPHERE_POINTS];
+
+	btVector3	supportVerticesABatch[NUM_UNITSPHERE_POINTS+MAX_PREFERRED_PENETRATION_DIRECTIONS*2];
+	btVector3	supportVerticesBBatch[NUM_UNITSPHERE_POINTS+MAX_PREFERRED_PENETRATION_DIRECTIONS*2];
+	btVector3	seperatingAxisInABatch[NUM_UNITSPHERE_POINTS+MAX_PREFERRED_PENETRATION_DIRECTIONS*2];
+	btVector3	seperatingAxisInBBatch[NUM_UNITSPHERE_POINTS+MAX_PREFERRED_PENETRATION_DIRECTIONS*2];
 	int i;
 
-	for (i=0;i<NUM_UNITSPHERE_POINTS;i++)
+	int numSampleDirections = NUM_UNITSPHERE_POINTS;
+
+	for (i=0;i<numSampleDirections;i++)
 	{
 		const btVector3& norm = sPenetrationDirections[i];
-		seperatingAxisInABatch[i] = (-norm)* transA.getBasis();
-		seperatingAxisInBBatch[i] = norm * transB.getBasis();
+		seperatingAxisInABatch[i] =  (-norm) * transA.getBasis() ;
+		seperatingAxisInBBatch[i] =  norm   * transB.getBasis() ;
 	}
 
-	convexA->batchedUnitVectorGetSupportingVertexWithoutMargin(seperatingAxisInABatch,supportVerticesABatch,NUM_UNITSPHERE_POINTS);
-	convexB->batchedUnitVectorGetSupportingVertexWithoutMargin(seperatingAxisInBBatch,supportVerticesBBatch,NUM_UNITSPHERE_POINTS);
-	for (i=0;i<NUM_UNITSPHERE_POINTS;i++)
+	{
+		int numPDA = convexA->getNumPreferredPenetrationDirections();
+		if (numPDA)
+		{
+			for (int i=0;i<numPDA;i++)
+			{
+				btVector3 norm;
+				convexA->getPreferredPenetrationDirection(i,norm);
+				norm  = transA.getBasis() * norm;
+				sPenetrationDirections[numSampleDirections] = norm;
+				seperatingAxisInABatch[numSampleDirections] = (-norm) * transA.getBasis();
+				seperatingAxisInBBatch[numSampleDirections] = norm * transB.getBasis();
+				numSampleDirections++;
+			}
+		}
+	}
+
+	{
+		int numPDB = convexB->getNumPreferredPenetrationDirections();
+		if (numPDB)
+		{
+			for (int i=0;i<numPDB;i++)
+			{
+				btVector3 norm;
+				convexB->getPreferredPenetrationDirection(i,norm);
+				norm  = transB.getBasis() * norm;
+				sPenetrationDirections[numSampleDirections] = norm;
+				seperatingAxisInABatch[numSampleDirections] = (-norm) * transA.getBasis();
+				seperatingAxisInBBatch[numSampleDirections] = norm * transB.getBasis();
+				numSampleDirections++;
+			}
+		}
+	}
+
+
+
+	convexA->batchedUnitVectorGetSupportingVertexWithoutMargin(seperatingAxisInABatch,supportVerticesABatch,numSampleDirections);
+	convexB->batchedUnitVectorGetSupportingVertexWithoutMargin(seperatingAxisInBBatch,supportVerticesBBatch,numSampleDirections);
+
+	for (i=0;i<numSampleDirections;i++)
 	{
 		const btVector3& norm = sPenetrationDirections[i];
 		seperatingAxisInA = seperatingAxisInABatch[i];
@@ -148,7 +188,40 @@ bool btMinkowskiPenetrationDepthSolver::calcPenDepth(btSimplexSolverInterface& s
 		}
 	}	
 #else
-	for (int i=0;i<NUM_UNITSPHERE_POINTS;i++)
+
+	int numSampleDirections = NUM_UNITSPHERE_POINTS;
+
+	{
+		int numPDA = convexA->getNumPreferredPenetrationDirections();
+		if (numPDA)
+		{
+			for (int i=0;i<numPDA;i++)
+			{
+				btVector3 norm;
+				convexA->getPreferredPenetrationDirection(i,norm);
+				norm  = transA.getBasis() * norm;
+				sPenetrationDirections[numSampleDirections] = norm;
+				numSampleDirections++;
+			}
+		}
+	}
+
+	{
+		int numPDB = convexB->getNumPreferredPenetrationDirections();
+		if (numPDB)
+		{
+			for (int i=0;i<numPDB;i++)
+			{
+				btVector3 norm;
+				convexB->getPreferredPenetrationDirection(i,norm);
+				norm  = transB.getBasis() * norm;
+				sPenetrationDirections[numSampleDirections] = norm;
+				numSampleDirections++;
+			}
+		}
+	}
+
+	for (int i=0;i<numSampleDirections;i++)
 	{
 		const btVector3& norm = sPenetrationDirections[i];
 		seperatingAxisInA = (-norm)* transA.getBasis();