fix for restitution

added preliminary continuous dynamics world (under construction, not ready yet)
fix crash on when restarting simplex demo using spacebar, Thanks Jorrit Tyberghein for reporting!

Demos/OpenGL/DemoApplication.cpp

@@ -911,11 +911,12 @@ void	DemoApplication::clientResetScene()
 	gNumGjkChecks = 0;
 #endif //SHOW_NUM_DEEP_PENETRATIONS
 
+	int numObjects = 0;
 	if (m_dynamicsWorld)
 	{
 		m_dynamicsWorld->stepSimulation(1.f/60.f,0);
+		numObjects = m_dynamicsWorld->getNumCollisionObjects();
 	}
-	int numObjects = m_dynamicsWorld->getNumCollisionObjects();
 	
 	for (int i=0;i<numObjects;i++)
 	{

src/BulletCollision/CollisionDispatch/btCollisionWorld.cpp

@@ -152,6 +152,7 @@ void	btCollisionWorld::performDiscreteCollisionDetection()
 }
 
 
+
 void	btCollisionWorld::removeCollisionObject(btCollisionObject* collisionObject)
 {
 	

src/BulletDynamics/ConstraintSolver/btSequentialImpulseConstraintSolver.cpp

@@ -496,21 +496,22 @@ btScalar btSequentialImpulseConstraintSolver::solveGroupCacheFriendly(btCollisio
 
 							solverConstraint.m_penetration = cp.getDistance();///btScalar(infoGlobal.m_numIterations);
 							solverConstraint.m_friction = cp.m_combinedFriction;
-							btScalar rest =  restitutionCurve(rel_vel, cp.m_combinedRestitution);
-							if (rest <= btScalar(0.))
+							solverConstraint.m_restitution =  restitutionCurve(rel_vel, cp.m_combinedRestitution);
+							if (solverConstraint.m_restitution <= btScalar(0.))
 							{
-								rest = 0.f;
+								solverConstraint.m_restitution = 0.f;
 							};
 							
 							btScalar penVel = -solverConstraint.m_penetration/infoGlobal.m_timeStep;
-							if (rest > penVel)
-							{
-								rest = btScalar(0.);
-							}
-							solverConstraint.m_restitution = rest;
-
 							solverConstraint.m_penetration *= -(infoGlobal.m_erp/infoGlobal.m_timeStep);
 
+							if (solverConstraint.m_restitution > penVel)
+							{
+								solverConstraint.m_penetration = btScalar(0.);
+							}
+							
+							
+
 							solverConstraint.m_appliedImpulse = 0.f;
 							solverConstraint.m_appliedVelocityImpulse = 0.f;
 							

src/BulletDynamics/Dynamics/btContinuousDynamicsWorld.cpp

@@ -0,0 +1,195 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2007 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 "btContinuousDynamicsWorld.h"
+#include "LinearMath/btQuickprof.h"
+
+//collision detection
+#include "BulletCollision/CollisionDispatch/btCollisionDispatcher.h"
+#include "BulletCollision/BroadphaseCollision/btSimpleBroadphase.h"
+#include "BulletCollision/CollisionShapes/btCollisionShape.h"
+#include "BulletCollision/CollisionDispatch/btSimulationIslandManager.h"
+
+//rigidbody & constraints
+#include "BulletDynamics/Dynamics/btRigidBody.h"
+#include "BulletDynamics/ConstraintSolver/btSequentialImpulseConstraintSolver.h"
+#include "BulletDynamics/ConstraintSolver/btContactSolverInfo.h"
+#include "BulletDynamics/ConstraintSolver/btTypedConstraint.h"
+
+
+
+#include <stdio.h>
+
+btContinuousDynamicsWorld::btContinuousDynamicsWorld(btDispatcher* dispatcher,btBroadphaseInterface* pairCache,btConstraintSolver* constraintSolver)
+:btDiscreteDynamicsWorld(dispatcher,pairCache,constraintSolver)
+{
+}
+
+btContinuousDynamicsWorld::~btContinuousDynamicsWorld()
+{
+}
+
+	
+void	btContinuousDynamicsWorld::internalSingleStepSimulation( btScalar timeStep)
+{
+	
+	startProfiling(timeStep);
+
+	///update aabbs information
+	updateAabbs();
+	static int frame=0;
+//	printf("frame %d\n",frame++);
+
+	///apply gravity, predict motion
+	predictUnconstraintMotion(timeStep);
+
+	btDispatcherInfo& dispatchInfo = getDispatchInfo();
+
+	dispatchInfo.m_timeStep = timeStep;
+	dispatchInfo.m_stepCount = 0;
+	dispatchInfo.m_debugDraw = getDebugDrawer();
+
+	///perform collision detection
+	performDiscreteCollisionDetection();
+
+	calculateSimulationIslands();
+
+	
+	getSolverInfo().m_timeStep = timeStep;
+	
+
+
+	///solve contact and other joint constraints
+	solveConstraints(getSolverInfo());
+	
+	///CallbackTriggers();
+
+	calculateTimeOfImpacts(timeStep);
+
+	btScalar toi = dispatchInfo.m_timeOfImpact;
+//	if (toi < 1.f)
+//		printf("toi = %f\n",toi);
+	if (toi < 0.f)
+		printf("toi = %f\n",toi);
+
+
+	///integrate transforms
+	integrateTransforms(timeStep * toi);
+
+	///update vehicle simulation
+	updateVehicles(timeStep);
+
+
+	updateActivationState( timeStep );
+	
+}
+
+void	btContinuousDynamicsWorld::calculateTimeOfImpacts(btScalar timeStep)
+{
+		///these should be 'temporal' aabbs!
+		updateTemporalAabbs(timeStep);
+		
+		///'toi' is the global smallest time of impact. However, we just calculate the time of impact for each object individually.
+		///so we handle the case moving versus static properly, and we cheat for moving versus moving
+		float toi = 1.f;
+		
+	
+		btDispatcherInfo& dispatchInfo = getDispatchInfo();
+		dispatchInfo.m_timeStep = timeStep;
+		dispatchInfo.m_timeOfImpact = 1.f;
+		dispatchInfo.m_stepCount = 0;
+		dispatchInfo.m_dispatchFunc = btDispatcherInfo::DISPATCH_CONTINUOUS;
+
+		///calculate time of impact for overlapping pairs
+
+		BEGIN_PROFILE("performContinuousCollisionDetection");
+
+		btDispatcher* dispatcher = getDispatcher();
+		if (dispatcher)
+			dispatcher->dispatchAllCollisionPairs(m_broadphasePairCache->getOverlappingPairCache(),dispatchInfo,m_dispatcher1);
+
+		END_PROFILE("performContinuousCollisionDetection");
+
+		toi = dispatchInfo.m_timeOfImpact;
+
+		dispatchInfo.m_dispatchFunc = btDispatcherInfo::DISPATCH_DISCRETE;
+
+}
+
+void	btContinuousDynamicsWorld::updateTemporalAabbs(btScalar timeStep)
+{
+	BEGIN_PROFILE("perform Temporal Broadphase Collision Detection");
+
+	btVector3 temporalAabbMin,temporalAabbMax;
+
+	for ( int i=0;i<m_collisionObjects.size();i++)
+	{
+		btCollisionObject* colObj = m_collisionObjects[i];
+		
+		btRigidBody* body = btRigidBody::upcast(colObj);
+		if (body)
+		{
+			body->getCollisionShape()->getAabb(m_collisionObjects[i]->getWorldTransform(),temporalAabbMin,temporalAabbMax);
+			const btVector3& linvel = body->getLinearVelocity();
+			const btVector3& angvel = body->getAngularVelocity();
+
+			//make the AABB temporal
+			float temporalAabbMaxx = temporalAabbMax.getX();
+			float temporalAabbMaxy = temporalAabbMax.getY();
+			float temporalAabbMaxz = temporalAabbMax.getZ();
+			float temporalAabbMinx = temporalAabbMin.getX();
+			float temporalAabbMiny = temporalAabbMin.getY();
+			float temporalAabbMinz = temporalAabbMin.getZ();
+
+			// add linear motion
+			btVector3 linMotion = linvel*timeStep;
+		
+			if (linMotion.x() > 0.f)
+				temporalAabbMaxx += linMotion.x(); 
+			else
+				temporalAabbMinx += linMotion.x();
+			if (linMotion.y() > 0.f)
+				temporalAabbMaxy += linMotion.y(); 
+			else
+				temporalAabbMiny += linMotion.y();
+			if (linMotion.z() > 0.f)
+				temporalAabbMaxz += linMotion.z(); 
+			else
+				temporalAabbMinz += linMotion.z();
+
+			//add conservative angular motion
+			btScalar angularMotion(0);// = angvel.length() * GetAngularMotionDisc() * timeStep;
+			btVector3 angularMotion3d(angularMotion,angularMotion,angularMotion);
+			temporalAabbMin = btVector3(temporalAabbMinx,temporalAabbMiny,temporalAabbMinz);
+			temporalAabbMax = btVector3(temporalAabbMaxx,temporalAabbMaxy,temporalAabbMaxz);
+
+			temporalAabbMin -= angularMotion3d;
+			temporalAabbMax += angularMotion3d;
+
+			m_broadphasePairCache->setAabb(body->getBroadphaseHandle(),temporalAabbMin,temporalAabbMax);
+		}
+	}
+
+	//update aabb (of all moved objects)
+
+	m_broadphasePairCache->calculateOverlappingPairs(m_dispatcher1);
+	
+	END_PROFILE("perform Temporal Broadphase Collision Detection");
+
+
+}
+
+

src/BulletDynamics/Dynamics/btContinuousDynamicsWorld.h

@@ -0,0 +1,41 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2007 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_CONTINUOUS_DYNAMICS_WORLD_H
+#define BT_CONTINUOUS_DYNAMICS_WORLD_H
+
+#include "btDiscreteDynamicsWorld.h"
+
+///btContinuousDynamicsWorld adds optional (per object) continuous collision detection for fast moving objects to the btDiscreteDynamicsWorld.
+///This copes with fast moving objects that otherwise would tunnel/miss collisions.
+///Under construction, don't use yet!
+class btContinuousDynamicsWorld : public btDiscreteDynamicsWorld
+{
+
+	void	updateTemporalAabbs(btScalar timeStep);
+
+	public:
+
+		btContinuousDynamicsWorld(btDispatcher* dispatcher,btBroadphaseInterface* pairCache,btConstraintSolver* constraintSolver);
+		virtual ~btContinuousDynamicsWorld();
+		
+		///time stepping with calculation of time of impact for selected fast moving objects
+		virtual void	internalSingleStepSimulation( btScalar timeStep);
+
+		virtual void	calculateTimeOfImpacts(btScalar timeStep);
+
+};
+
+#endif //BT_CONTINUOUS_DYNAMICS_WORLD_H

src/btBulletDynamicsCommon.h

@@ -20,6 +20,8 @@ subject to the following restrictions:
 #include "btBulletCollisionCommon.h"
 
 #include "BulletDynamics/Dynamics/btDiscreteDynamicsWorld.h"
+#include "BulletDynamics/Dynamics/btContinuousDynamicsWorld.h"
+
 #include "BulletDynamics/Dynamics/btSimpleDynamicsWorld.h"
 #include "BulletDynamics/Dynamics/btRigidBody.h"