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deformable code refactor

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This commit is contained in:
Xuchen Han
2019-07-21 18:32:54 -07:00
parent dc10336d45
commit a90cad2a96
17 changed files with 1065 additions and 382 deletions
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148
src/BulletSoftBody/btDeformableRigidDynamicsWorld.cpp
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@@ -12,87 +12,78 @@
void btDeformableRigidDynamicsWorld::internalSingleStepSimulation(btScalar timeStep)
{
m_internalTime += timeStep;
// Let the solver grab the soft bodies and if necessary optimize for it
m_deformableBodySolver->optimize(m_softBodies);
reinitialize(timeStep);
if (!m_deformableBodySolver->checkInitialized())
{
btAssert("Solver initialization failed\n");
}
// from btDiscreteDynamicsWorld singleStepSimulation
if (0 != m_internalPreTickCallback)
{
(*m_internalPreTickCallback)(this, timeStep);
}
// add gravity to velocity of rigid and multi bodys
applyRigidBodyGravity(timeStep);
///apply gravity, predict motion
///apply gravity and explicit force to velocity, predict motion
predictUnconstraintMotion(timeStep);
btDispatcherInfo& dispatchInfo = btMultiBodyDynamicsWorld::getDispatchInfo();
dispatchInfo.m_timeStep = timeStep;
dispatchInfo.m_stepCount = 0;
dispatchInfo.m_debugDraw = btMultiBodyDynamicsWorld::getDebugDrawer();
// only used in CCD
// createPredictiveContacts(timeStep);
///perform collision detection
btMultiBodyDynamicsWorld::performDiscreteCollisionDetection();
btMultiBodyDynamicsWorld::calculateSimulationIslands();
btMultiBodyDynamicsWorld::getSolverInfo().m_timeStep = timeStep;
if (0 != m_internalTickCallback)
{
(*m_internalTickCallback)(this, timeStep);
}
beforeSolverCallbacks(timeStep);
// TODO: This is an ugly hack to get the desired gravity behavior.
// gravity is applied in stepSimulation and then cleared here and then applied here and then cleared here again
// so that 1) gravity is applied to velocity before constraint solve and 2) gravity is applied in each substep
// when there are multiple substeps
clearForces();
clearMultiBodyForces();
btMultiBodyDynamicsWorld::applyGravity();
// integrate rigid body gravity
for (int i = 0; i < m_nonStaticRigidBodies.size(); ++i)
{
btRigidBody* rb = m_nonStaticRigidBodies[i];
rb->integrateVelocities(timeStep);
}
// integrate multibody gravity
btMultiBodyDynamicsWorld::solveExternalForces(btMultiBodyDynamicsWorld::getSolverInfo());
clearForces();
clearMultiBodyForces();
for (int i = 0; i < before_solver_callbacks.size(); ++i)
before_solver_callbacks[i](m_internalTime, this);
///solve deformable bodies constraints
solveDeformableBodiesConstraints(timeStep);
positionCorrection();
//integrate transforms
btMultiBodyDynamicsWorld::integrateTransforms(timeStep);
integrateTransforms(timeStep);
///update vehicle simulation
btMultiBodyDynamicsWorld::updateActions(timeStep);
btMultiBodyDynamicsWorld::updateActivationState(timeStep);
///update soft bodies
m_deformableBodySolver->updateSoftBodies();
clearForces();
// End solver-wise simulation step
// ///////////////////////////////
}
void btDeformableRigidDynamicsWorld::positionCorrection()
{
// perform position correction for all geometric collisions
for (int i = 0; i < m_softBodies.size(); ++i)
{
btSoftBody* psb = m_softBodies[i];
const btScalar mrg = psb->getCollisionShape()->getMargin();
for (int j = 0; j < psb->m_rcontacts.size(); ++j)
{
const btSoftBody::RContact& c = psb->m_rcontacts[j];
// skip anchor points
if (c.m_node->m_im == 0)
continue;
const btSoftBody::sCti& cti = c.m_cti;
if (cti.m_colObj->hasContactResponse())
{
btScalar dp = btMin((btDot(c.m_node->m_x, cti.m_normal) + cti.m_offset), mrg);
if (dp < 0)
{
// m_c4 is the collision hardness
c.m_node->m_q -= dp * cti.m_normal * c.m_c4;
}
}
}
}
}
void btDeformableRigidDynamicsWorld::integrateTransforms(btScalar dt)
{
btMultiBodyDynamicsWorld::integrateTransforms(dt);
for (int i = 0; i < m_softBodies.size(); ++i)
{
btSoftBody* psb = m_softBodies[i];
for (int j = 0; j < psb->m_nodes.size(); ++j)
{
auto& node = psb->m_nodes[j];
node.m_x = node.m_q + dt * node.m_v;
}
}
}
void btDeformableRigidDynamicsWorld::solveDeformableBodiesConstraints(btScalar timeStep)
{
m_deformableBodySolver->solveConstraints(timeStep);
@@ -117,4 +108,45 @@ void btDeformableRigidDynamicsWorld::predictUnconstraintMotion(btScalar timeStep
m_deformableBodySolver->predictMotion(float(timeStep));
}
void btDeformableRigidDynamicsWorld::reinitialize(btScalar timeStep)
{
m_internalTime += timeStep;
m_deformableBodySolver->reinitialize(m_softBodies);
btDispatcherInfo& dispatchInfo = btMultiBodyDynamicsWorld::getDispatchInfo();
dispatchInfo.m_timeStep = timeStep;
dispatchInfo.m_stepCount = 0;
dispatchInfo.m_debugDraw = btMultiBodyDynamicsWorld::getDebugDrawer();
btMultiBodyDynamicsWorld::getSolverInfo().m_timeStep = timeStep;
}
void btDeformableRigidDynamicsWorld::applyRigidBodyGravity(btScalar timeStep)
{
// TODO: This is an ugly hack to get the desired gravity behavior.
// gravity is applied in stepSimulation and then cleared here and then applied here and then cleared here again
// so that 1) gravity is applied to velocity before constraint solve and 2) gravity is applied in each substep
// when there are multiple substeps
clearForces();
clearMultiBodyForces();
btMultiBodyDynamicsWorld::applyGravity();
// integrate rigid body gravity
for (int i = 0; i < m_nonStaticRigidBodies.size(); ++i)
{
btRigidBody* rb = m_nonStaticRigidBodies[i];
rb->integrateVelocities(timeStep);
}
// integrate multibody gravity
btMultiBodyDynamicsWorld::solveExternalForces(btMultiBodyDynamicsWorld::getSolverInfo());
clearForces();
clearMultiBodyForces();
}
void btDeformableRigidDynamicsWorld::beforeSolverCallbacks(btScalar timeStep)
{
if (0 != m_internalTickCallback)
{
(*m_internalTickCallback)(this, timeStep);
}
for (int i = 0; i < m_beforeSolverCallbacks.size(); ++i)
m_beforeSolverCallbacks[i](m_internalTime, this);
}