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Attempt to fix "Regression in friction and damping behaviour" , see issue 752

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Thanks to Sergej Reich for the report and narrowing down the breaking revision!
This commit is contained in:
erwin.coumans@gmail.com
2013-10-22 09:26:08 +00:00
parent 5e372d6ac5
commit a21480c8ca
5 changed files with 84 additions and 58 deletions
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108
src/BulletDynamics/ConstraintSolver/btSequentialImpulseConstraintSolver.cpp
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@@ -280,7 +280,7 @@ int btSequentialImpulseConstraintSolver::btRandInt2 (int n)
void btSequentialImpulseConstraintSolver::initSolverBody(btSolverBody* solverBody, btCollisionObject* collisionObject)
void btSequentialImpulseConstraintSolver::initSolverBody(btSolverBody* solverBody, btCollisionObject* collisionObject, btScalar timeStep)
{
btRigidBody* rb = collisionObject? btRigidBody::upcast(collisionObject) : 0;
@@ -299,8 +299,8 @@ void btSequentialImpulseConstraintSolver::initSolverBody(btSolverBody* solverBod
solverBody->m_linearFactor = rb->getLinearFactor();
solverBody->m_linearVelocity = rb->getLinearVelocity();
solverBody->m_angularVelocity = rb->getAngularVelocity();
solverBody->m_externalForce = rb->getTotalForce();
solverBody->m_externalTorque = rb->getTotalTorque();
solverBody->m_externalForceImpulse = rb->getTotalForce()*rb->getInvMass()*timeStep;
solverBody->m_externalTorqueImpulse = rb->getTotalTorque()*rb->getInvInertiaTensorWorld()*timeStep ;
} else
{
@@ -311,8 +311,8 @@ void btSequentialImpulseConstraintSolver::initSolverBody(btSolverBody* solverBod
solverBody->m_linearFactor.setValue(1,1,1);
solverBody->m_linearVelocity.setValue(0,0,0);
solverBody->m_angularVelocity.setValue(0,0,0);
solverBody->m_externalForce.setValue(0,0,0);
solverBody->m_externalTorque.setValue(0,0,0);
solverBody->m_externalForceImpulse.setValue(0,0,0);
solverBody->m_externalTorqueImpulse.setValue(0,0,0);
}
@@ -418,10 +418,10 @@ void btSequentialImpulseConstraintSolver::setupFrictionConstraint(btSolverConstr
btScalar rel_vel;
btScalar vel1Dotn = solverConstraint.m_contactNormal1.dot(body0?body0->getLinearVelocity():btVector3(0,0,0))
+ solverConstraint.m_relpos1CrossNormal.dot(body0?body0->getAngularVelocity():btVector3(0,0,0));
btScalar vel2Dotn = solverConstraint.m_contactNormal2.dot(body1?body1->getLinearVelocity():btVector3(0,0,0))
+ solverConstraint.m_relpos2CrossNormal.dot(body1?body1->getAngularVelocity():btVector3(0,0,0));
btScalar vel1Dotn = solverConstraint.m_contactNormal1.dot(body0?solverBodyA.m_linearVelocity+solverBodyA.m_externalForceImpulse:btVector3(0,0,0))
+ solverConstraint.m_relpos1CrossNormal.dot(body0?solverBodyA.m_angularVelocity:btVector3(0,0,0));
btScalar vel2Dotn = solverConstraint.m_contactNormal2.dot(body1?solverBodyB.m_linearVelocity+solverBodyB.m_externalForceImpulse:btVector3(0,0,0))
+ solverConstraint.m_relpos2CrossNormal.dot(body1?solverBodyB.m_angularVelocity:btVector3(0,0,0));
rel_vel = vel1Dotn+vel2Dotn;
@@ -498,10 +498,10 @@ void btSequentialImpulseConstraintSolver::setupRollingFrictionConstraint( btSolv
btScalar rel_vel;
btScalar vel1Dotn = solverConstraint.m_contactNormal1.dot(body0?body0->getLinearVelocity():btVector3(0,0,0))
+ solverConstraint.m_relpos1CrossNormal.dot(body0?body0->getAngularVelocity():btVector3(0,0,0));
btScalar vel2Dotn = solverConstraint.m_contactNormal2.dot(body1?body1->getLinearVelocity():btVector3(0,0,0))
+ solverConstraint.m_relpos2CrossNormal.dot(body1?body1->getAngularVelocity():btVector3(0,0,0));
btScalar vel1Dotn = solverConstraint.m_contactNormal1.dot(body0?solverBodyA.m_linearVelocity+solverBodyA.m_externalForceImpulse:btVector3(0,0,0))
+ solverConstraint.m_relpos1CrossNormal.dot(body0?solverBodyA.m_angularVelocity:btVector3(0,0,0));
btScalar vel2Dotn = solverConstraint.m_contactNormal2.dot(body1?solverBodyB.m_linearVelocity+solverBodyB.m_externalForceImpulse:btVector3(0,0,0))
+ solverConstraint.m_relpos2CrossNormal.dot(body1?solverBodyB.m_angularVelocity:btVector3(0,0,0));
rel_vel = vel1Dotn+vel2Dotn;
@@ -534,7 +534,7 @@ btSolverConstraint& btSequentialImpulseConstraintSolver::addRollingFrictionConst
}
int btSequentialImpulseConstraintSolver::getOrInitSolverBody(btCollisionObject& body)
int btSequentialImpulseConstraintSolver::getOrInitSolverBody(btCollisionObject& body,btScalar timeStep)
{
int solverBodyIdA = -1;
@@ -552,7 +552,7 @@ int btSequentialImpulseConstraintSolver::getOrInitSolverBody(btCollisionObject&
{
solverBodyIdA = m_tmpSolverBodyPool.size();
btSolverBody& solverBody = m_tmpSolverBodyPool.expand();
initSolverBody(&solverBody,&body);
initSolverBody(&solverBody,&body,timeStep);
body.setCompanionId(solverBodyIdA);
} else
{
@@ -561,7 +561,7 @@ int btSequentialImpulseConstraintSolver::getOrInitSolverBody(btCollisionObject&
{
m_fixedBodyId = m_tmpSolverBodyPool.size();
btSolverBody& fixedBody = m_tmpSolverBodyPool.expand();
initSolverBody(&fixedBody,0);
initSolverBody(&fixedBody,0,timeStep);
}
return m_fixedBodyId;
// return 0;//assume first one is a fixed solver body
@@ -577,8 +577,8 @@ int btSequentialImpulseConstraintSolver::getOrInitSolverBody(btCollisionObject&
void btSequentialImpulseConstraintSolver::setupContactConstraint(btSolverConstraint& solverConstraint,
int solverBodyIdA, int solverBodyIdB,
btManifoldPoint& cp, const btContactSolverInfo& infoGlobal,
btVector3& vel, btScalar& rel_vel, btScalar& relaxation,
btVector3& rel_pos1, btVector3& rel_pos2)
btScalar& relaxation,
const btVector3& rel_pos1, const btVector3& rel_pos2)
{
const btVector3& pos1 = cp.getPositionWorldOnA();
@@ -592,8 +592,8 @@ void btSequentialImpulseConstraintSolver::setupContactConstraint(btSolverConstra
// btVector3 rel_pos1 = pos1 - colObj0->getWorldTransform().getOrigin();
// btVector3 rel_pos2 = pos2 - colObj1->getWorldTransform().getOrigin();
rel_pos1 = pos1 - bodyA->getWorldTransform().getOrigin();
rel_pos2 = pos2 - bodyB->getWorldTransform().getOrigin();
//rel_pos1 = pos1 - bodyA->getWorldTransform().getOrigin();
//rel_pos2 = pos2 - bodyB->getWorldTransform().getOrigin();
relaxation = 1.f;
@@ -655,8 +655,8 @@ void btSequentialImpulseConstraintSolver::setupContactConstraint(btSolverConstra
vel2 = rb1? rb1->getVelocityInLocalPoint(rel_pos2) : btVector3(0,0,0);
// btVector3 vel2 = rb1 ? rb1->getVelocityInLocalPoint(rel_pos2) : btVector3(0,0,0);
vel = vel1 - vel2;
rel_vel = cp.m_normalWorldOnB.dot(vel);
btVector3 vel = vel1 - vel2;
btScalar rel_vel = cp.m_normalWorldOnB.dot(vel);
@@ -688,10 +688,10 @@ void btSequentialImpulseConstraintSolver::setupContactConstraint(btSolverConstra
{
btVector3 externalForceImpulseA = bodyA->m_originalBody ? bodyA->m_externalForce*bodyA->m_invMass*infoGlobal.m_timeStep : btVector3(0,0,0);
btVector3 externalTorqueImpulseA = bodyA->m_originalBody ? bodyA->m_externalTorque*rb0->getInvInertiaTensorWorld()*infoGlobal.m_timeStep : btVector3(0,0,0);
btVector3 externalForceImpulseB = bodyB->m_originalBody ? bodyB->m_externalForce*bodyB->m_invMass*infoGlobal.m_timeStep : btVector3(0,0,0);
btVector3 externalTorqueImpulseB = bodyB->m_originalBody ?bodyB->m_externalTorque*rb1->getInvInertiaTensorWorld()*infoGlobal.m_timeStep : btVector3(0,0,0);
btVector3 externalForceImpulseA = bodyA->m_originalBody ? bodyA->m_externalForceImpulse: btVector3(0,0,0);
btVector3 externalTorqueImpulseA = bodyA->m_originalBody ? bodyA->m_externalTorqueImpulse: btVector3(0,0,0);
btVector3 externalForceImpulseB = bodyB->m_originalBody ? bodyB->m_externalForceImpulse: btVector3(0,0,0);
btVector3 externalTorqueImpulseB = bodyB->m_originalBody ?bodyB->m_externalTorqueImpulse : btVector3(0,0,0);
btScalar vel1Dotn = solverConstraint.m_contactNormal1.dot(bodyA->m_linearVelocity+externalForceImpulseA)
@@ -800,8 +800,8 @@ void btSequentialImpulseConstraintSolver::convertContact(btPersistentManifold* m
colObj0 = (btCollisionObject*)manifold->getBody0();
colObj1 = (btCollisionObject*)manifold->getBody1();
int solverBodyIdA = getOrInitSolverBody(*colObj0);
int solverBodyIdB = getOrInitSolverBody(*colObj1);
int solverBodyIdA = getOrInitSolverBody(*colObj0,infoGlobal.m_timeStep);
int solverBodyIdB = getOrInitSolverBody(*colObj1,infoGlobal.m_timeStep);
// btRigidBody* bodyA = btRigidBody::upcast(colObj0);
// btRigidBody* bodyB = btRigidBody::upcast(colObj1);
@@ -826,8 +826,7 @@ void btSequentialImpulseConstraintSolver::convertContact(btPersistentManifold* m
btVector3 rel_pos1;
btVector3 rel_pos2;
btScalar relaxation;
btScalar rel_vel;
btVector3 vel;
int frictionIndex = m_tmpSolverContactConstraintPool.size();
btSolverConstraint& solverConstraint = m_tmpSolverContactConstraintPool.expandNonInitializing();
@@ -838,7 +837,24 @@ void btSequentialImpulseConstraintSolver::convertContact(btPersistentManifold* m
solverConstraint.m_originalContactPoint = &cp;
setupContactConstraint(solverConstraint, solverBodyIdA, solverBodyIdB, cp, infoGlobal, vel, rel_vel, relaxation, rel_pos1, rel_pos2);
const btVector3& pos1 = cp.getPositionWorldOnA();
const btVector3& pos2 = cp.getPositionWorldOnB();
rel_pos1 = pos1 - colObj0->getWorldTransform().getOrigin();
rel_pos2 = pos2 - colObj1->getWorldTransform().getOrigin();
btVector3 vel1;// = rb0 ? rb0->getVelocityInLocalPoint(rel_pos1) : btVector3(0,0,0);
btVector3 vel2;// = rb1 ? rb1->getVelocityInLocalPoint(rel_pos2) : btVector3(0,0,0);
solverBodyA->getVelocityInLocalPointNoDelta(rel_pos1,vel1);
solverBodyB->getVelocityInLocalPointNoDelta(rel_pos2,vel2 );
btVector3 vel = vel1 - vel2;
btScalar rel_vel = cp.m_normalWorldOnB.dot(vel);
setupContactConstraint(solverConstraint, solverBodyIdA, solverBodyIdB, cp, infoGlobal, relaxation, rel_pos1, rel_pos2);
// const btVector3& pos1 = cp.getPositionWorldOnA();
// const btVector3& pos2 = cp.getPositionWorldOnB();
@@ -947,8 +963,8 @@ void btSequentialImpulseConstraintSolver::convertContact(btPersistentManifold* m
if ((infoGlobal.m_solverMode & SOLVER_USE_2_FRICTION_DIRECTIONS))
addFrictionConstraint(cp.m_lateralFrictionDir2,solverBodyIdA,solverBodyIdB,frictionIndex,cp,rel_pos1,rel_pos2,colObj0,colObj1, relaxation, cp.m_contactMotion2, cp.m_contactCFM2);
setFrictionConstraintImpulse( solverConstraint, solverBodyIdA, solverBodyIdB, cp, infoGlobal);
}
setFrictionConstraintImpulse( solverConstraint, solverBodyIdA, solverBodyIdB, cp, infoGlobal);
@@ -1065,7 +1081,7 @@ btScalar btSequentialImpulseConstraintSolver::solveGroupCacheFriendlySetup(btCol
for (int i=0;i<numBodies;i++)
{
int bodyId = getOrInitSolverBody(*bodies[i]);
int bodyId = getOrInitSolverBody(*bodies[i],infoGlobal.m_timeStep);
btRigidBody* body = btRigidBody::upcast(bodies[i]);
if (body && body->getInvMass())
@@ -1075,7 +1091,7 @@ btScalar btSequentialImpulseConstraintSolver::solveGroupCacheFriendlySetup(btCol
if (body->getFlags()&BT_ENABLE_GYROPSCOPIC_FORCE)
{
gyroForce = body->computeGyroscopicForce(infoGlobal.m_maxGyroscopicForce);
solverBody.m_externalTorque -= gyroForce;
solverBody.m_externalTorqueImpulse -= gyroForce*body->getInvInertiaTensorWorld()*infoGlobal.m_timeStep;
}
}
}
@@ -1146,8 +1162,8 @@ btScalar btSequentialImpulseConstraintSolver::solveGroupCacheFriendlySetup(btCol
btRigidBody& rbA = constraint->getRigidBodyA();
btRigidBody& rbB = constraint->getRigidBodyB();
int solverBodyIdA = getOrInitSolverBody(rbA);
int solverBodyIdB = getOrInitSolverBody(rbB);
int solverBodyIdA = getOrInitSolverBody(rbA,infoGlobal.m_timeStep);
int solverBodyIdB = getOrInitSolverBody(rbB,infoGlobal.m_timeStep);
btSolverBody* bodyAPtr = &m_tmpSolverBodyPool[solverBodyIdA];
btSolverBody* bodyBPtr = &m_tmpSolverBodyPool[solverBodyIdB];
@@ -1247,11 +1263,11 @@ btScalar btSequentialImpulseConstraintSolver::solveGroupCacheFriendlySetup(btCol
{
btScalar rel_vel;
btVector3 externalForceImpulseA = bodyAPtr->m_originalBody ? bodyAPtr->m_externalForce*bodyAPtr->m_invMass*infoGlobal.m_timeStep : btVector3(0,0,0);
btVector3 externalTorqueImpulseA = bodyAPtr->m_originalBody ? bodyAPtr->m_externalTorque*rbA.getInvInertiaTensorWorld()*infoGlobal.m_timeStep : btVector3(0,0,0);
btVector3 externalForceImpulseA = bodyAPtr->m_originalBody ? bodyAPtr->m_externalForceImpulse : btVector3(0,0,0);
btVector3 externalTorqueImpulseA = bodyAPtr->m_originalBody ? bodyAPtr->m_externalTorqueImpulse : btVector3(0,0,0);
btVector3 externalForceImpulseB = bodyBPtr->m_originalBody ? bodyBPtr->m_externalForce*bodyBPtr->m_invMass*infoGlobal.m_timeStep : btVector3(0,0,0);
btVector3 externalTorqueImpulseB = bodyBPtr->m_originalBody ?bodyBPtr->m_externalTorque*rbB.getInvInertiaTensorWorld()*infoGlobal.m_timeStep : btVector3(0,0,0);
btVector3 externalForceImpulseB = bodyBPtr->m_originalBody ? bodyBPtr->m_externalForceImpulse : btVector3(0,0,0);
btVector3 externalTorqueImpulseB = bodyBPtr->m_originalBody ?bodyBPtr->m_externalTorqueImpulse : btVector3(0,0,0);
btScalar vel1Dotn = solverConstraint.m_contactNormal1.dot(rbA.getLinearVelocity()+externalForceImpulseA)
+ solverConstraint.m_relpos1CrossNormal.dot(rbA.getAngularVelocity()+externalTorqueImpulseA);
@@ -1371,8 +1387,8 @@ btScalar btSequentialImpulseConstraintSolver::solveSingleIteration(int iteration
{
if (constraints[j]->isEnabled())
{
int bodyAid = getOrInitSolverBody(constraints[j]->getRigidBodyA());
int bodyBid = getOrInitSolverBody(constraints[j]->getRigidBodyB());
int bodyAid = getOrInitSolverBody(constraints[j]->getRigidBodyA(),infoGlobal.m_timeStep);
int bodyBid = getOrInitSolverBody(constraints[j]->getRigidBodyB(),infoGlobal.m_timeStep);
btSolverBody& bodyA = m_tmpSolverBodyPool[bodyAid];
btSolverBody& bodyB = m_tmpSolverBodyPool[bodyBid];
constraints[j]->solveConstraintObsolete(bodyA,bodyB,infoGlobal.m_timeStep);
@@ -1501,8 +1517,8 @@ btScalar btSequentialImpulseConstraintSolver::solveSingleIteration(int iteration
{
if (constraints[j]->isEnabled())
{
int bodyAid = getOrInitSolverBody(constraints[j]->getRigidBodyA());
int bodyBid = getOrInitSolverBody(constraints[j]->getRigidBodyB());
int bodyAid = getOrInitSolverBody(constraints[j]->getRigidBodyA(),infoGlobal.m_timeStep);
int bodyBid = getOrInitSolverBody(constraints[j]->getRigidBodyB(),infoGlobal.m_timeStep);
btSolverBody& bodyA = m_tmpSolverBodyPool[bodyAid];
btSolverBody& bodyB = m_tmpSolverBodyPool[bodyBid];
constraints[j]->solveConstraintObsolete(bodyA,bodyB,infoGlobal.m_timeStep);
@@ -1675,11 +1691,11 @@ btScalar btSequentialImpulseConstraintSolver::solveGroupCacheFriendlyFinish(btCo
m_tmpSolverBodyPool[i].m_originalBody->setLinearVelocity(
m_tmpSolverBodyPool[i].m_linearVelocity+
m_tmpSolverBodyPool[i].m_externalForce*body->getInvMass()*infoGlobal.m_timeStep);
m_tmpSolverBodyPool[i].m_externalForceImpulse);
m_tmpSolverBodyPool[i].m_originalBody->setAngularVelocity(
m_tmpSolverBodyPool[i].m_angularVelocity+
m_tmpSolverBodyPool[i].m_externalTorque*body->getInvInertiaTensorWorld()*infoGlobal.m_timeStep);
m_tmpSolverBodyPool[i].m_externalTorqueImpulse);
if (infoGlobal.m_splitImpulse)
m_tmpSolverBodyPool[i].m_originalBody->setWorldTransform(m_tmpSolverBodyPool[i].m_worldTransform);

7
src/BulletDynamics/ConstraintSolver/btSequentialImpulseConstraintSolver.h
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@@ -58,8 +58,7 @@ protected:
void setupContactConstraint(btSolverConstraint& solverConstraint, int solverBodyIdA, int solverBodyIdB, btManifoldPoint& cp,
const btContactSolverInfo& infoGlobal, btVector3& vel, btScalar& rel_vel, btScalar& relaxation,
btVector3& rel_pos1, btVector3& rel_pos2);
const btContactSolverInfo& infoGlobal,btScalar& relaxation, const btVector3& rel_pos1, const btVector3& rel_pos2);
static void applyAnisotropicFriction(btCollisionObject* colObj,btVector3& frictionDirection, int frictionMode);
@@ -86,8 +85,8 @@ protected:
const btSolverConstraint& contactConstraint);
//internal method
int getOrInitSolverBody(btCollisionObject& body);
void initSolverBody(btSolverBody* solverBody, btCollisionObject* collisionObject);
int getOrInitSolverBody(btCollisionObject& body,btScalar timeStep);
void initSolverBody(btSolverBody* solverBody, btCollisionObject* collisionObject, btScalar timeStep);
void resolveSingleConstraintRowGeneric(btSolverBody& bodyA,btSolverBody& bodyB,const btSolverConstraint& contactConstraint);

15
src/BulletDynamics/ConstraintSolver/btSolverBody.h
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@@ -118,8 +118,8 @@ ATTRIBUTE_ALIGNED16 (struct) btSolverBody
btVector3 m_turnVelocity;
btVector3 m_linearVelocity;
btVector3 m_angularVelocity;
btVector3 m_externalForce;
btVector3 m_externalTorque;
btVector3 m_externalForceImpulse;
btVector3 m_externalTorqueImpulse;
btRigidBody* m_originalBody;
void setWorldTransform(const btTransform& worldTransform)
@@ -132,6 +132,17 @@ ATTRIBUTE_ALIGNED16 (struct) btSolverBody
return m_worldTransform;
}
SIMD_FORCE_INLINE void getVelocityInLocalPointNoDelta(const btVector3& rel_pos, btVector3& velocity ) const
{
if (m_originalBody)
velocity = m_linearVelocity + m_externalForceImpulse + (m_angularVelocity+m_externalTorqueImpulse).cross(rel_pos);
else
velocity.setValue(0,0,0);
}
SIMD_FORCE_INLINE void getVelocityInLocalPointObsolete(const btVector3& rel_pos, btVector3& velocity ) const
{
if (m_originalBody)

4
src/BulletDynamics/Dynamics/btDiscreteDynamicsWorld.cpp
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@@ -973,6 +973,8 @@ void btDiscreteDynamicsWorld::integrateTransforms(btScalar timeStep)
if (body->isActive() && (!body->isStaticOrKinematicObject()))
{
body->applyDamping(timeStep);
body->predictIntegratedTransform(timeStep, predictedTrans);
btScalar squareMotion = (predictedTrans.getOrigin()-body->getWorldTransform().getOrigin()).length2();
@@ -1119,8 +1121,6 @@ void btDiscreteDynamicsWorld::predictUnconstraintMotion(btScalar timeStep)
{
//don't integrate/update velocities here, it happens in the constraint solver
//damping
body->applyDamping(timeStep);
body->predictIntegratedTransform(timeStep,body->getInterpolationWorldTransform());
}

8
src/BulletDynamics/Featherstone/btMultiBodyConstraintSolver.cpp
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@@ -540,8 +540,8 @@ btMultiBodySolverConstraint& btMultiBodyConstraintSolver::addMultiBodyFrictionCo
btMultiBody* mbA = fcA? fcA->m_multiBody : 0;
btMultiBody* mbB = fcB? fcB->m_multiBody : 0;
int solverBodyIdA = mbA? -1 : getOrInitSolverBody(*colObj0);
int solverBodyIdB = mbB ? -1 : getOrInitSolverBody(*colObj1);
int solverBodyIdA = mbA? -1 : getOrInitSolverBody(*colObj0,infoGlobal.m_timeStep);
int solverBodyIdB = mbB ? -1 : getOrInitSolverBody(*colObj1,infoGlobal.m_timeStep);
solverConstraint.m_solverBodyIdA = solverBodyIdA;
solverConstraint.m_solverBodyIdB = solverBodyIdB;
@@ -572,8 +572,8 @@ void btMultiBodyConstraintSolver::convertMultiBodyContact(btPersistentManifold*
colObj0 = (btCollisionObject*)manifold->getBody0();
colObj1 = (btCollisionObject*)manifold->getBody1();
int solverBodyIdA = mbA? -1 : getOrInitSolverBody(*colObj0);
int solverBodyIdB = mbB ? -1 : getOrInitSolverBody(*colObj1);
int solverBodyIdA = mbA? -1 : getOrInitSolverBody(*colObj0,infoGlobal.m_timeStep);
int solverBodyIdB = mbB ? -1 : getOrInitSolverBody(*colObj1,infoGlobal.m_timeStep);
btSolverBody* solverBodyA = mbA ? 0 : &m_tmpSolverBodyPool[solverBodyIdA];
btSolverBody* solverBodyB = mbB ? 0 : &m_tmpSolverBodyPool[solverBodyIdB];