void PhysicsEngine::stepSimulation() {
CProfileManager::Reset();
BT_PROFILE("stepSimulation");
// NOTE: the grand order of operations is:
// (1) pull incoming changes
// (2) step simulation
// (3) synchronize outgoing motion states
// (4) send outgoing packets
const float MAX_TIMESTEP = (float)PHYSICS_ENGINE_MAX_NUM_SUBSTEPS * PHYSICS_ENGINE_FIXED_SUBSTEP;
float dt = 1.0e-6f * (float)(_clock.getTimeMicroseconds());
_clock.reset();
float timeStep = btMin(dt, MAX_TIMESTEP);
if (_myAvatarController) {
BT_PROFILE("avatarController");
// TODO: move this stuff outside and in front of stepSimulation, because
// the updateShapeIfNecessary() call needs info from MyAvatar and should
// be done on the main thread during the pre-simulation stuff
if (_myAvatarController->needsRemoval()) {
_myAvatarController->setDynamicsWorld(nullptr);
// We must remove any existing contacts for the avatar so that any new contacts will have
// valid data. MyAvatar's RigidBody is the ONLY one in the simulation that does not yet
// have a MotionState so we pass nullptr to removeContacts().
removeContacts(nullptr);
}
_myAvatarController->updateShapeIfNecessary();
if (_myAvatarController->needsAddition()) {
_myAvatarController->setDynamicsWorld(_dynamicsWorld);
}
_myAvatarController->preSimulation();
}
auto onSubStep = [this]() {
updateContactMap();
};
int numSubsteps = _dynamicsWorld->stepSimulationWithSubstepCallback(timeStep, PHYSICS_ENGINE_MAX_NUM_SUBSTEPS,
PHYSICS_ENGINE_FIXED_SUBSTEP, onSubStep);
if (numSubsteps > 0) {
BT_PROFILE("postSimulation");
_numSubsteps += (uint32_t)numSubsteps;
ObjectMotionState::setWorldSimulationStep(_numSubsteps);
if (_myAvatarController) {
_myAvatarController->postSimulation();
}
_hasOutgoingChanges = true;
}
}
void PhysicsEngine::stepSimulation() {
CProfileManager::Reset();
BT_PROFILE("stepSimulation");
// NOTE: the grand order of operations is:
// (1) pull incoming changes
// (2) step simulation
// (3) synchronize outgoing motion states
// (4) send outgoing packets
const float MAX_TIMESTEP = (float)PHYSICS_ENGINE_MAX_NUM_SUBSTEPS * PHYSICS_ENGINE_FIXED_SUBSTEP;
float dt = 1.0e-6f * (float)(_clock.getTimeMicroseconds());
_clock.reset();
float timeStep = btMin(dt, MAX_TIMESTEP);
// TODO: move character->preSimulation() into relayIncomingChanges
if (_characterController) {
if (_characterController->needsRemoval()) {
_characterController->setDynamicsWorld(nullptr);
}
_characterController->updateShapeIfNecessary();
if (_characterController->needsAddition()) {
_characterController->setDynamicsWorld(_dynamicsWorld);
}
_characterController->preSimulation(timeStep);
}
int numSubsteps = _dynamicsWorld->stepSimulation(timeStep, PHYSICS_ENGINE_MAX_NUM_SUBSTEPS, PHYSICS_ENGINE_FIXED_SUBSTEP);
if (numSubsteps > 0) {
BT_PROFILE("postSimulation");
_numSubsteps += (uint32_t)numSubsteps;
ObjectMotionState::setWorldSimulationStep(_numSubsteps);
if (_characterController) {
_characterController->postSimulation();
}
updateContactMap();
_hasOutgoingChanges = true;
}
}