overte-Armored-Dragon/libraries/physics/src/ThreadSafeDynamicsWorld.cpp
2014-12-02 15:29:41 -08:00

89 lines
3.1 KiB
C++

/*
* Bullet Continuous Collision Detection and Physics Library
* Copyright (c) 2003-2009 Erwin Coumans http://bulletphysics.org
*
* 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.
*
* Copied and modified from btDiscreteDynamicsWorld.cpp by AndrewMeadows on 2014.11.12.
* */
#include <EntityTree.h>
#include "ThreadSafeDynamicsWorld.h"
ThreadSafeDynamicsWorld::ThreadSafeDynamicsWorld(
btDispatcher* dispatcher,
btBroadphaseInterface* pairCache,
btConstraintSolver* constraintSolver,
btCollisionConfiguration* collisionConfiguration,
EntityTree* entities)
: btDiscreteDynamicsWorld(dispatcher, pairCache, constraintSolver, collisionConfiguration) {
assert(entities);
_entities = entities;
}
void ThreadSafeDynamicsWorld::synchronizeMotionStates() {
_entities->lockForWrite();
btDiscreteDynamicsWorld::synchronizeMotionStates();
_entities->unlock();
}
int ThreadSafeDynamicsWorld::stepSimulation( btScalar timeStep, int maxSubSteps, btScalar fixedTimeStep) {
int subSteps = 0;
if (maxSubSteps) {
//fixed timestep with interpolation
m_fixedTimeStep = fixedTimeStep;
m_localTime += timeStep;
if (m_localTime >= fixedTimeStep)
{
subSteps = int( m_localTime / fixedTimeStep);
m_localTime -= subSteps * fixedTimeStep;
}
} else {
//variable timestep
fixedTimeStep = timeStep;
m_localTime = m_latencyMotionStateInterpolation ? 0 : timeStep;
m_fixedTimeStep = 0;
if (btFuzzyZero(timeStep))
{
subSteps = 0;
maxSubSteps = 0;
} else
{
subSteps = 1;
maxSubSteps = 1;
}
}
/*//process some debugging flags
if (getDebugDrawer()) {
btIDebugDraw* debugDrawer = getDebugDrawer ();
gDisableDeactivation = (debugDrawer->getDebugMode() & btIDebugDraw::DBG_NoDeactivation) != 0;
}*/
if (subSteps) {
//clamp the number of substeps, to prevent simulation grinding spiralling down to a halt
int clampedSimulationSteps = (subSteps > maxSubSteps)? maxSubSteps : subSteps;
saveKinematicState(fixedTimeStep*clampedSimulationSteps);
applyGravity();
for (int i=0;i<clampedSimulationSteps;i++) {
internalSingleStepSimulation(fixedTimeStep);
}
}
// We only sync motion states once at the end of all substeps.
// This is to avoid placing multiple, repeated thread locks on _entities.
synchronizeMotionStates();
clearForces();
return subSteps;
}