Thanks to Mårten Svanfeldt for the contribution:

- optionally disable collisions between bodies that are linked with constraints
- improved debug rendering with support for compounds, spheres, capsules

src/BulletCollision/CollisionDispatch/btCollisionDispatcher.cpp

@@ -273,6 +273,8 @@ bool	btCollisionDispatcher::needsCollision(btCollisionObject* body0,btCollisionO
 		
 	if ((!body0->isActive()) && (!body1->isActive()))
 		needsCollision = false;
+	else if (!body0->checkCollideWith(body1))
+		needsCollision = false;
 	
 	return needsCollision ;
 

src/BulletCollision/CollisionDispatch/btCollisionObject.cpp

@@ -24,7 +24,8 @@ btCollisionObject::btCollisionObject()
 		m_userObjectPointer(0),
 		m_hitFraction(btScalar(1.)),
 		m_ccdSweptSphereRadius(btScalar(0.)),
-		m_ccdSquareMotionThreshold(btScalar(0.))
+		m_ccdSquareMotionThreshold(btScalar(0.)),
+		m_checkCollideWith(false)
 {
 	
 }

src/BulletCollision/CollisionDispatch/btCollisionObject.h

@@ -69,15 +69,23 @@ protected:
 	void*			m_internalOwner;
 
 	///time of impact calculation
-	btScalar			m_hitFraction; 
+	btScalar		m_hitFraction; 
 	
 	///Swept sphere radius (0.0 by default), see btConvexConvexAlgorithm::
-	btScalar			m_ccdSweptSphereRadius;
+	btScalar		m_ccdSweptSphereRadius;
 
 	/// Don't do continuous collision detection if square motion (in one step) is less then m_ccdSquareMotionThreshold
-	btScalar			m_ccdSquareMotionThreshold;
+	btScalar		m_ccdSquareMotionThreshold;
 	
-	char	m_pad[8];
+	/// If some object should have elaborate collision filtering by sub-classes
+	bool			m_checkCollideWith;
+
+	char	m_pad[7];
+
+	virtual bool	checkCollideWithOverride(btCollisionObject* co)
+	{
+		return true;
+	}
 
 public:
 
@@ -159,7 +167,7 @@ public:
 		return ((getActivationState() != ISLAND_SLEEPING) && (getActivationState() != DISABLE_SIMULATION));
 	}
 
-		void	setRestitution(btScalar rest)
+	void	setRestitution(btScalar rest)
 	{
 		m_restitution = rest;
 	}
@@ -322,6 +330,15 @@ public:
 		m_userObjectPointer = userPointer;
 	}
 
+	inline bool checkCollideWith(btCollisionObject* co)
+	{
+		if (m_checkCollideWith)
+			return checkCollideWithOverride(co);
+
+		return true;
+	}
+
+
 }
 ;
 

src/BulletCollision/CollisionShapes/btHeightfieldTerrainShape.cpp

@@ -290,16 +290,32 @@ void	btHeightfieldTerrainShape::processAllTriangles(btTriangleCallback* callback
 		for(int x=startX; x<endX; x++)
 		{
 			btVector3 vertices[3];
-			//first triangle
+			if (!m_flipQuadEdges)
-			getVertex(x,j,vertices[0]);
+			{
-			getVertex(x,j+1,vertices[1]);
+				//first triangle
-			getVertex(x+1,j,vertices[2]);
+				getVertex(x,j,vertices[0]);
-			callback->processTriangle(vertices,x,j);
+				getVertex(x,j+1,vertices[1]);
-			//second triangle
+				getVertex(x+1,j,vertices[2]);
-			getVertex(x+1,j,vertices[0]);
+				callback->processTriangle(vertices,x,j);
-			getVertex(x,j+1,vertices[1]);
+				//second triangle
-			getVertex(x+1,j+1,vertices[2]);
+				getVertex(x+1,j,vertices[0]);
-			callback->processTriangle(vertices,x,j);
+				getVertex(x,j+1,vertices[1]);
+				getVertex(x+1,j+1,vertices[2]);
+				callback->processTriangle(vertices,x,j);
+			} else
+			{
+				//first triangle
+				getVertex(x,j,vertices[0]);
+				getVertex(x+1,j,vertices[1]);
+				getVertex(x+1,j+1,vertices[2]);
+				callback->processTriangle(vertices,x,j);
+				//second triangle
+				getVertex(x,j,vertices[0]);
+				getVertex(x+1,j+1,vertices[1]);
+				getVertex(x,j+1,vertices[2]);
+				callback->processTriangle(vertices,x,j);
+				
+			}
 		}
 	}
 

src/BulletCollision/CollisionShapes/btMultiSphereShape.h

@@ -46,6 +46,20 @@ public:
 
 	virtual void	batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const;
 	
+	int	getSphereCount() const
+	{
+		return m_numSpheres;
+	}
+
+	const btVector3&	getSpherePosition(int index) const
+	{
+		return m_localPositions[index];
+	}
+
+	btScalar	getSphereRadius(int index) const
+	{
+		return m_radi[index];
+	}
 
 	virtual int	getShapeType() const { return MULTI_SPHERE_SHAPE_PROXYTYPE; }
 

src/BulletDynamics/Dynamics/btDiscreteDynamicsWorld.h

@@ -1,154 +1,155 @@
-/*
+/*
-Bullet Continuous Collision Detection and Physics Library
+Bullet Continuous Collision Detection and Physics Library
-Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
-
+
-This software is provided 'as-is', without any express or implied warranty.
+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.
+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, 
+Permission is granted to anyone to use this software for any purpose, 
-including commercial applications, and to alter it and redistribute it freely, 
+including commercial applications, and to alter it and redistribute it freely, 
-subject to the following restrictions:
+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.
+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.
+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.
+3. This notice may not be removed or altered from any source distribution.
-*/
+*/
-
+
-#ifndef BT_DISCRETE_DYNAMICS_WORLD_H
+#ifndef BT_DISCRETE_DYNAMICS_WORLD_H
-#define BT_DISCRETE_DYNAMICS_WORLD_H
+#define BT_DISCRETE_DYNAMICS_WORLD_H
-
+
-#include "btDynamicsWorld.h"
+#include "btDynamicsWorld.h"
-
+
-class btDispatcher;
+class btDispatcher;
-class btOverlappingPairCache;
+class btOverlappingPairCache;
-class btConstraintSolver;
+class btConstraintSolver;
-class btSimulationIslandManager;
+class btSimulationIslandManager;
-class btTypedConstraint;
+class btTypedConstraint;
-#include "../ConstraintSolver/btContactSolverInfo.h"
+#include "../ConstraintSolver/btContactSolverInfo.h"
-
+
-class btRaycastVehicle;
+class btRaycastVehicle;
-class btIDebugDraw;
+class btIDebugDraw;
-#include "../../LinearMath/btAlignedObjectArray.h"
+#include "../../LinearMath/btAlignedObjectArray.h"
-
+
-
+
-///btDiscreteDynamicsWorld provides discrete rigid body simulation
+///btDiscreteDynamicsWorld provides discrete rigid body simulation
-///those classes replace the obsolete CcdPhysicsEnvironment/CcdPhysicsController
+///those classes replace the obsolete CcdPhysicsEnvironment/CcdPhysicsController
-class btDiscreteDynamicsWorld : public btDynamicsWorld
+class btDiscreteDynamicsWorld : public btDynamicsWorld
-{
+{
-protected:
+protected:
-
+
-	btConstraintSolver*	m_constraintSolver;
+	btConstraintSolver*	m_constraintSolver;
-
+
-	btSimulationIslandManager*	m_islandManager;
+	btSimulationIslandManager*	m_islandManager;
-
+
-	btAlignedObjectArray<btTypedConstraint*> m_constraints;
+	btAlignedObjectArray<btTypedConstraint*> m_constraints;
-
+
-	btIDebugDraw*	m_debugDrawer;
+	btIDebugDraw*	m_debugDrawer;
-
+
-	btVector3	m_gravity;
+	btVector3	m_gravity;
-
+
-	//for variable timesteps
+	//for variable timesteps
-	btScalar	m_localTime;
+	btScalar	m_localTime;
-	//for variable timesteps
+	//for variable timesteps
-
+
-	bool	m_ownsIslandManager;
+	bool	m_ownsIslandManager;
-	bool	m_ownsConstraintSolver;
+	bool	m_ownsConstraintSolver;
-
+
-	btContactSolverInfo	m_solverInfo;
+	btContactSolverInfo	m_solverInfo;
-
+
-
+
-	btAlignedObjectArray<btRaycastVehicle*>	m_vehicles;
+	btAlignedObjectArray<btRaycastVehicle*>	m_vehicles;
-
+
-	int	m_profileTimings;
+	int	m_profileTimings;
-
+
-	void	predictUnconstraintMotion(btScalar timeStep);
+	void	predictUnconstraintMotion(btScalar timeStep);
-	
+	
-	void	integrateTransforms(btScalar timeStep);
+	void	integrateTransforms(btScalar timeStep);
-		
+		
-	void	calculateSimulationIslands();
+	void	calculateSimulationIslands();
-
+
-	void	solveConstraints(btContactSolverInfo& solverInfo);
+	void	solveConstraints(btContactSolverInfo& solverInfo);
-	
+	
-	void	updateActivationState(btScalar timeStep);
+	void	updateActivationState(btScalar timeStep);
-
+
-	void	updateVehicles(btScalar timeStep);
+	void	updateVehicles(btScalar timeStep);
-
+
-	void	startProfiling(btScalar timeStep);
+	void	startProfiling(btScalar timeStep);
-
+
-	virtual void	internalSingleStepSimulation( btScalar timeStep);
+	virtual void	internalSingleStepSimulation( btScalar timeStep);
-
+
-	void	synchronizeMotionStates();
+	void	synchronizeMotionStates();
-
+
-	void	saveKinematicState(btScalar timeStep);
+	void	saveKinematicState(btScalar timeStep);
-
+
-
+	void	debugDrawSphere(btScalar radius, const btTransform& transform, const btVector3& color);
-public:
+
-
+public:
-
+
-	///this btDiscreteDynamicsWorld constructor gets created objects from the user, and will not delete those
+
-	btDiscreteDynamicsWorld(btDispatcher* dispatcher,btOverlappingPairCache* pairCache,btConstraintSolver* constraintSolver);
+	///this btDiscreteDynamicsWorld constructor gets created objects from the user, and will not delete those
-
+	btDiscreteDynamicsWorld(btDispatcher* dispatcher,btOverlappingPairCache* pairCache,btConstraintSolver* constraintSolver);
-	virtual ~btDiscreteDynamicsWorld();
+
-
+	virtual ~btDiscreteDynamicsWorld();
-	///if maxSubSteps > 0, it will interpolate motion between fixedTimeStep's
+
-	virtual int	stepSimulation( btScalar timeStep,int maxSubSteps=1, btScalar fixedTimeStep=btScalar(1.)/btScalar(60.));
+	///if maxSubSteps > 0, it will interpolate motion between fixedTimeStep's
-
+	virtual int	stepSimulation( btScalar timeStep,int maxSubSteps=1, btScalar fixedTimeStep=btScalar(1.)/btScalar(60.));
-	virtual void	updateAabbs();
+
-
+	virtual void	updateAabbs();
-	void	addConstraint(btTypedConstraint* constraint);
+
-
+	void	addConstraint(btTypedConstraint* constraint, bool disableCollisionsBetweenLinkedBodies=false);
-	void	removeConstraint(btTypedConstraint* constraint);
+
-
+	void	removeConstraint(btTypedConstraint* constraint);
-	void	addVehicle(btRaycastVehicle* vehicle);
+
-
+	void	addVehicle(btRaycastVehicle* vehicle);
-	void	removeVehicle(btRaycastVehicle* vehicle);
+
-
+	void	removeVehicle(btRaycastVehicle* vehicle);
-	btSimulationIslandManager*	getSimulationIslandManager()
+
-	{
+	btSimulationIslandManager*	getSimulationIslandManager()
-		return m_islandManager;
+	{
-	}
+		return m_islandManager;
-
+	}
-	const btSimulationIslandManager*	getSimulationIslandManager() const 
+
-	{
+	const btSimulationIslandManager*	getSimulationIslandManager() const 
-		return m_islandManager;
+	{
-	}
+		return m_islandManager;
-
+	}
-	btCollisionWorld*	getCollisionWorld()
+
-	{
+	btCollisionWorld*	getCollisionWorld()
-		return this;
+	{
-	}
+		return this;
-
+	}
-	virtual void	setDebugDrawer(btIDebugDraw*	debugDrawer)
+
-	{
+	virtual void	setDebugDrawer(btIDebugDraw*	debugDrawer)
-			m_debugDrawer = debugDrawer;
+	{
-	}
+			m_debugDrawer = debugDrawer;
-
+	}
-	virtual btIDebugDraw*	getDebugDrawer()
+
-	{
+	virtual btIDebugDraw*	getDebugDrawer()
-		return m_debugDrawer;
+	{
-	}
+		return m_debugDrawer;
-
+	}
-	virtual void	setGravity(const btVector3& gravity);
+
-
+	virtual void	setGravity(const btVector3& gravity);
-	virtual void	addRigidBody(btRigidBody* body);
+
-
+	virtual void	addRigidBody(btRigidBody* body);
-	virtual void	removeRigidBody(btRigidBody* body);
+
-
+	virtual void	removeRigidBody(btRigidBody* body);
-	void	debugDrawObject(const btTransform& worldTransform, const btCollisionShape* shape, const btVector3& color);
+
-
+	void	debugDrawObject(const btTransform& worldTransform, const btCollisionShape* shape, const btVector3& color);
-	virtual void	setConstraintSolver(btConstraintSolver* solver);
+
-	
+	virtual void	setConstraintSolver(btConstraintSolver* solver);
-	virtual	int		getNumConstraints() const;
+	
-
+	virtual	int		getNumConstraints() const;
-	virtual btTypedConstraint* getConstraint(int index)	;
+
-
+	virtual btTypedConstraint* getConstraint(int index)	;
-	virtual const btTypedConstraint* getConstraint(int index) const;
+
-
+	virtual const btTypedConstraint* getConstraint(int index) const;
-	btContactSolverInfo& getSolverInfo()
+
-	{
+	btContactSolverInfo& getSolverInfo()
-		return m_solverInfo;
+	{
-	}
+		return m_solverInfo;
-
+	}
-
+
-};
+
-
+};
-#endif //BT_DISCRETE_DYNAMICS_WORLD_H
+
+#endif //BT_DISCRETE_DYNAMICS_WORLD_H

src/BulletDynamics/Dynamics/btRigidBody.cpp

@@ -16,8 +16,9 @@ subject to the following restrictions:
 #include "btRigidBody.h"
 #include "BulletCollision/CollisionShapes/btConvexShape.h"
 #include "LinearMath/btMinMax.h"
-#include <LinearMath/btTransformUtil.h>
+#include "LinearMath/btTransformUtil.h"
-#include <LinearMath/btMotionState.h>
+#include "LinearMath/btMotionState.h"
+#include "BulletDynamics/ConstraintSolver/btTypedConstraint.h"
 
 btScalar gLinearAirDamping = btScalar(1.);
 //'temporarily' global variables
@@ -305,4 +306,33 @@ void btRigidBody::setCenterOfMassTransform(const btTransform& xform)
 }
 
 
+bool btRigidBody::checkCollideWithOverride(btCollisionObject* co)
+{
+	btRigidBody* otherRb = btRigidBody::upcast(co);
+	if (!otherRb)
+		return true;
 
+	for (int i = 0; i < m_constraintRefs.size(); ++i)
+	{
+		btTypedConstraint* c = m_constraintRefs[i];
+		if (&c->getRigidBodyA() == otherRb || &c->getRigidBodyB() == otherRb)
+			return false;
+	}
+
+	return true;
+}
+
+void btRigidBody::addConstraintRef(btTypedConstraint* c)
+{
+	int index = m_constraintRefs.findLinearSearch(c);
+	if (index == m_constraintRefs.size())
+		m_constraintRefs.push_back(c); 
+
+	m_checkCollideWith = true;
+}
+
+void btRigidBody::removeConstraintRef(btTypedConstraint* c)
+{
+	m_constraintRefs.remove(c);
+	m_checkCollideWith = m_constraintRefs.size() > 0;
+}

src/BulletDynamics/Dynamics/btRigidBody.h

@@ -16,6 +16,7 @@ subject to the following restrictions:
 #ifndef RIGIDBODY_H
 #define RIGIDBODY_H
 
+#include "../../LinearMath/btAlignedObjectArray.h"
 #include "../../LinearMath/btPoint3.h"
 #include "../../LinearMath/btTransform.h"
 #include "../../BulletCollision/BroadphaseCollision/btBroadphaseProxy.h"
@@ -23,7 +24,7 @@ subject to the following restrictions:
 
 class btCollisionShape;
 class btMotionState;
-
+class btTypedConstraint;
 
 
 extern btScalar gLinearAirDamping;
@@ -57,6 +58,9 @@ class btRigidBody  : public btCollisionObject
 	//m_optionalMotionState allows to automatic synchronize the world transform for active objects
 	btMotionState*	m_optionalMotionState;
 
+	//keep track of typed constraints referencing this rigid body
+	btAlignedObjectArray<btTypedConstraint*> m_constraintRefs;
+
 public:
 
 #ifdef OBSOLETE_MOTIONSTATE_LESS
@@ -339,6 +343,11 @@ public:
 		return (getBroadphaseProxy() != 0);
 	}
 
+	virtual bool checkCollideWithOverride(btCollisionObject* co);
+
+	void addConstraintRef(btTypedConstraint* c);
+	void removeConstraintRef(btTypedConstraint* c);
+
 	int	m_debugBodyId;
 };