void PhysicsWorld::performTimestep(float seconds)
{
for (auto & body : m_rigidBodies)
{
body->applyForce({0.0f, -m_gravity * body->mass(), 0.0f});
body->integrateVelocities(seconds);
body->updateWorldInertia();
}
/**
* Update broadphase
*/
for (auto & body : m_rigidBodies)
{
m_broadphase->setProxyBounds(*body->proxy(), body->bounds());
}
m_broadphase->checkProximities();
m_narrowphase->updateContacts();
solve();
integrateTransforms(seconds);
/**
* Clear forces
*/
for (auto & body : m_rigidBodies)
{
body->setForce({});
}
}
void btContinuousDynamicsWorld::internalSingleStepSimulation( btScalar timeStep)
{
startProfiling(timeStep);
if(0 != m_internalPreTickCallback) {
(*m_internalPreTickCallback)(this, 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)
kdPrintf("toi = %f\n",toi);
///integrate transforms
integrateTransforms(timeStep * toi);
///update vehicle simulation
updateActions(timeStep);
updateActivationState( timeStep );
if(0 != m_internalTickCallback) {
(*m_internalTickCallback)(this, timeStep);
}
}
void btDiscreteDynamicsWorld::internalSingleStepSimulation(btScalar timeStep)
{
BT_PROFILE("internalSingleStepSimulation");
if(0 != m_internalPreTickCallback) {
(*m_internalPreTickCallback)(this, timeStep);
}
///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();
if (getDispatchInfo().m_useContinuous)
addSpeculativeContacts(timeStep);
calculateSimulationIslands();
getSolverInfo().m_timeStep = timeStep;
///solve contact and other joint constraints
solveConstraints(getSolverInfo());
///CallbackTriggers();
///integrate transforms
integrateTransforms(timeStep);
///update vehicle simulation
updateActions(timeStep);
updateActivationState( timeStep );
if(0 != m_internalTickCallback) {
(*m_internalTickCallback)(this, timeStep);
}
}
int btSimpleDynamicsWorld::stepSimulation( btScalar timeStep, int maxSubSteps, btScalar fixedTimeStep, btScalar fixedSubSteps)
{
(void)fixedTimeStep;
(void)maxSubSteps;
(void)fixedSubSteps;
///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();
///solve contact constraints
int numManifolds = m_dispatcher1->getNumManifolds();
if (numManifolds)
{
btPersistentManifold** manifoldPtr = ((btCollisionDispatcher*)m_dispatcher1)->getInternalManifoldPointer();
btContactSolverInfo infoGlobal;
infoGlobal.m_timeStep = timeStep;
m_constraintSolver->prepareSolve(0, numManifolds);
m_constraintSolver->solveGroup(&getCollisionObjectArray()[0], getNumCollisionObjects(), manifoldPtr, numManifolds,0,0, infoGlobal, m_debugDrawer, m_dispatcher1);
m_constraintSolver->allSolved(infoGlobal, m_debugDrawer);
}
///integrate transforms
integrateTransforms(timeStep);
updateAabbs();
synchronizeMotionStates();
clearForces();
return 1;
}