Avoid using restitution for ccd motion clamping. Restitution for fast moving objects should be handled by btDiscreteDynamicsWorld::createPredictiveContacts

(make sure to merge islands based on those predictive contacts too, added some check in the solver)
This fixes Issue 356.
Use same solver settings for AllBulletDemos
Make sure to embed the setCcdSweptSphereRadius inside the actual collision shape (for shoot box)

Demos/AllBulletDemos/Main.cpp

@@ -100,12 +100,12 @@ void	setDefaultSettings()
 	gDrawClusters=0;
 
 	gDebugNoDeactivation = 0;
-	gUseSplitImpulse = 0;
+	gUseSplitImpulse = 1;
 	gUseWarmstarting = 1;
-	gRandomizeConstraints = 1;
+	gRandomizeConstraints = 0;
 	gErp = 0.2f;
 	gSlop=0.0f;
-	gErp2 = 0.1f;
+	gErp2 = 0.81f;
 	gWarmStartingParameter = 0.85f;
 	
 }

Demos/OpenGL/DemoApplication.cpp

@@ -534,8 +534,8 @@ void	DemoApplication::setShootBoxShape ()
 {
 	if (!m_shootBoxShape)
 	{
-		btBoxShape* box = new btBoxShape(btVector3(.15f,.15f,.15f));
+		btBoxShape* box = new btBoxShape(btVector3(0.5,0.5,0.5));
-		box->initializePolyhedralFeatures();
+        box->initializePolyhedralFeatures();
 		m_shootBoxShape = box;
 	}
 }
@@ -565,8 +565,8 @@ void	DemoApplication::shootBox(const btVector3& destination)
 		body->getWorldTransform().setRotation(btQuaternion(0,0,0,1));
 		body->setLinearVelocity(linVel);
 		body->setAngularVelocity(btVector3(0,0,0));
-		body->setCcdMotionThreshold(0.1);
+		body->setCcdMotionThreshold(0.5);
-		body->setCcdSweptSphereRadius(0.1f);
+		body->setCcdSweptSphereRadius(0.4f);//value should be smaller (embedded) than the half extends of the box (see ::setShootBoxShape)
 //		printf("shootBox uid=%d\n", body->getBroadphaseHandle()->getUid());
 //		printf("camPos=%f,%f,%f\n",camPos.getX(),camPos.getY(),camPos.getZ());
 //		printf("destination=%f,%f,%f\n",destination.getX(),destination.getY(),destination.getZ());

src/BulletDynamics/ConstraintSolver/btContactConstraint.cpp

@@ -70,7 +70,7 @@ void	btContactConstraint::buildJacobian()
 
 
 
-//response  between two dynamic objects without friction, assuming 0 penetration depth
+//response  between two dynamic objects without friction and no restitution, assuming 0 penetration depth
 btScalar resolveSingleCollision(
         btRigidBody* body1,
         btCollisionObject* colObj2,
@@ -93,7 +93,7 @@ btScalar resolveSingleCollision(
     btScalar rel_vel;
     rel_vel = normal.dot(vel);
     
-    btScalar combinedRestitution = body1->getRestitution() * colObj2->getRestitution();
+    btScalar combinedRestitution = 0.f;
     btScalar restitution = combinedRestitution* -rel_vel;
 
     btScalar positionalError = solverInfo.m_erp *-distance /solverInfo.m_timeStep ;

src/BulletDynamics/ConstraintSolver/btSequentialImpulseConstraintSolver.cpp

@@ -781,6 +781,39 @@ btScalar btSequentialImpulseConstraintSolver::solveGroupCacheFriendlySetup(btCol
 
 	m_maxOverrideNumSolverIterations = 0;
 
+#ifdef BT_DEBUG
+    //make sure that dynamic bodies exist for all contact manifolds
+    for (int i=0;i<numManifolds;i++)
+    {
+        if (!manifoldPtr[i]->getBody0()->isStaticOrKinematicObject())
+        {
+            bool found=false;
+            for (int b=0;b<numBodies;b++)
+            {
+                
+                if (manifoldPtr[i]->getBody0()==bodies[b])
+                {
+                    found = true;
+                    break;
+                }
+            }
+            btAssert(found);
+        }
+        if (!manifoldPtr[i]->getBody1()->isStaticOrKinematicObject())
+        {
+            bool found=false;
+            for (int b=0;b<numBodies;b++)
+            {
+                if (manifoldPtr[i]->getBody1()==bodies[b])
+                {
+                    found = true;
+                    break;
+                }
+            }
+            btAssert(found);
+        }
+    }
+#endif //BT_DEBUG
 	
 	
 	for (int i = 0; i < numBodies; i++)

src/BulletDynamics/Dynamics/btDiscreteDynamicsWorld.cpp

@@ -481,10 +481,11 @@ void	btDiscreteDynamicsWorld::internalSingleStepSimulation(btScalar timeStep)
 	dispatchInfo.m_debugDraw = getDebugDrawer();
 
 
+    createPredictiveContacts(timeStep);
+    
 	///perform collision detection
 	performDiscreteCollisionDetection();
 
-	createPredictiveContacts(timeStep);
 
 	calculateSimulationIslands();
 
@@ -733,6 +734,28 @@ void	btDiscreteDynamicsWorld::calculateSimulationIslands()
 
 	getSimulationIslandManager()->updateActivationState(getCollisionWorld(),getCollisionWorld()->getDispatcher());
 
+    {
+        //merge islands based on speculative contact manifolds too
+        for (int i=0;i<this->m_predictiveManifolds.size();i++)
+        {
+            btPersistentManifold* manifold = m_predictiveManifolds[i];
+            
+            const btCollisionObject* colObj0 = manifold->getBody0();
+            const btCollisionObject* colObj1 = manifold->getBody1();
+            
+            if (((colObj0) && (!(colObj0)->isStaticOrKinematicObject())) &&
+                ((colObj1) && (!(colObj1)->isStaticOrKinematicObject())))
+            {
+                if (colObj0->isActive() || colObj1->isActive())
+                {
+                    
+                    getSimulationIslandManager()->getUnionFind().unite((colObj0)->getIslandTag(),
+                                                                       (colObj1)->getIslandTag());
+                }
+            }
+        }
+    }
+    
 	{
 		int i;
 		int numConstraints = int(m_constraints.size());
@@ -912,7 +935,7 @@ void	btDiscreteDynamicsWorld::createPredictiveContacts(btScalar timeStep)
 					btClosestNotMeConvexResultCallback sweepResults(body,body->getWorldTransform().getOrigin(),predictedTrans.getOrigin(),getBroadphase()->getOverlappingPairCache(),getDispatcher());
 #endif
 					//btConvexShape* convexShape = static_cast<btConvexShape*>(body->getCollisionShape());
-					btSphereShape tmpSphere(0.1);//body->getCcdSweptSphereRadius());//btConvexShape* convexShape = static_cast<btConvexShape*>(body->getCollisionShape());
+					btSphereShape tmpSphere(body->getCcdSweptSphereRadius());//btConvexShape* convexShape = static_cast<btConvexShape*>(body->getCollisionShape());
 					sweepResults.m_allowedPenetration=getDispatchInfo().m_allowedCcdPenetration;
 
 					sweepResults.m_collisionFilterGroup = body->getBroadphaseProxy()->m_collisionFilterGroup;