528 lines
16 KiB
C++
528 lines
16 KiB
C++
#include "btMultiBodyConstraint.h"
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#include "BulletDynamics/Dynamics/btRigidBody.h"
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btMultiBodyConstraint::btMultiBodyConstraint(btMultiBody* bodyA,btMultiBody* bodyB,int linkA, int linkB, int numRows, bool isUnilateral)
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:m_bodyA(bodyA),
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m_bodyB(bodyB),
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m_linkA(linkA),
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m_linkB(linkB),
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m_num_rows(numRows),
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m_isUnilateral(isUnilateral),
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m_maxAppliedImpulse(100)
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{
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m_jac_size_A = (6 + bodyA->getNumLinks());
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m_jac_size_both = (m_jac_size_A + (bodyB ? 6 + bodyB->getNumLinks() : 0));
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m_pos_offset = ((1 + m_jac_size_both)*m_num_rows);
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m_data.resize((2 + m_jac_size_both) * m_num_rows);
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}
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btMultiBodyConstraint::~btMultiBodyConstraint()
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{
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}
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btScalar btMultiBodyConstraint::fillConstraintRowMultiBodyMultiBody(btMultiBodySolverConstraint& constraintRow,
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btMultiBodyJacobianData& data,
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btScalar* jacOrgA,btScalar* jacOrgB,
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const btContactSolverInfo& infoGlobal,
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btScalar desiredVelocity,
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btScalar lowerLimit,
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btScalar upperLimit)
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{
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constraintRow.m_multiBodyA = m_bodyA;
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constraintRow.m_multiBodyB = m_bodyB;
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btMultiBody* multiBodyA = constraintRow.m_multiBodyA;
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btMultiBody* multiBodyB = constraintRow.m_multiBodyB;
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if (multiBodyA)
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{
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const int ndofA = multiBodyA->getNumLinks() + 6;
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constraintRow.m_deltaVelAindex = multiBodyA->getCompanionId();
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if (constraintRow.m_deltaVelAindex <0)
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{
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constraintRow.m_deltaVelAindex = data.m_deltaVelocities.size();
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multiBodyA->setCompanionId(constraintRow.m_deltaVelAindex);
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data.m_deltaVelocities.resize(data.m_deltaVelocities.size()+ndofA);
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} else
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{
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btAssert(data.m_deltaVelocities.size() >= constraintRow.m_deltaVelAindex+ndofA);
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}
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constraintRow.m_jacAindex = data.m_jacobians.size();
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data.m_jacobians.resize(data.m_jacobians.size()+ndofA);
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data.m_deltaVelocitiesUnitImpulse.resize(data.m_deltaVelocitiesUnitImpulse.size()+ndofA);
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btAssert(data.m_jacobians.size() == data.m_deltaVelocitiesUnitImpulse.size());
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for (int i=0;i<ndofA;i++)
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data.m_jacobians[constraintRow.m_jacAindex+i] = jacOrgA[i];
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btScalar* delta = &data.m_deltaVelocitiesUnitImpulse[constraintRow.m_jacAindex];
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multiBodyA->calcAccelerationDeltas(&data.m_jacobians[constraintRow.m_jacAindex],delta,data.scratch_r, data.scratch_v);
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}
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if (multiBodyB)
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{
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const int ndofB = multiBodyB->getNumLinks() + 6;
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constraintRow.m_deltaVelBindex = multiBodyB->getCompanionId();
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if (constraintRow.m_deltaVelBindex <0)
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{
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constraintRow.m_deltaVelBindex = data.m_deltaVelocities.size();
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multiBodyB->setCompanionId(constraintRow.m_deltaVelBindex);
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data.m_deltaVelocities.resize(data.m_deltaVelocities.size()+ndofB);
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}
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constraintRow.m_jacBindex = data.m_jacobians.size();
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data.m_jacobians.resize(data.m_jacobians.size()+ndofB);
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for (int i=0;i<ndofB;i++)
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data.m_jacobians[constraintRow.m_jacBindex+i] = jacOrgB[i];
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data.m_deltaVelocitiesUnitImpulse.resize(data.m_deltaVelocitiesUnitImpulse.size()+ndofB);
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btAssert(data.m_jacobians.size() == data.m_deltaVelocitiesUnitImpulse.size());
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multiBodyB->calcAccelerationDeltas(&data.m_jacobians[constraintRow.m_jacBindex],&data.m_deltaVelocitiesUnitImpulse[constraintRow.m_jacBindex],data.scratch_r, data.scratch_v);
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}
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{
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btVector3 vec;
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btScalar denom0 = 0.f;
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btScalar denom1 = 0.f;
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btScalar* jacB = 0;
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btScalar* jacA = 0;
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btScalar* lambdaA =0;
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btScalar* lambdaB =0;
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int ndofA = 0;
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if (multiBodyA)
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{
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ndofA = multiBodyA->getNumLinks() + 6;
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jacA = &data.m_jacobians[constraintRow.m_jacAindex];
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lambdaA = &data.m_deltaVelocitiesUnitImpulse[constraintRow.m_jacAindex];
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for (int i = 0; i < ndofA; ++i)
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{
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btScalar j = jacA[i] ;
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btScalar l =lambdaA[i];
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denom0 += j*l;
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}
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}
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if (multiBodyB)
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{
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const int ndofB = multiBodyB->getNumLinks() + 6;
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jacB = &data.m_jacobians[constraintRow.m_jacBindex];
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lambdaB = &data.m_deltaVelocitiesUnitImpulse[constraintRow.m_jacBindex];
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for (int i = 0; i < ndofB; ++i)
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{
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btScalar j = jacB[i] ;
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btScalar l =lambdaB[i];
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denom1 += j*l;
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}
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}
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if (multiBodyA && (multiBodyA==multiBodyB))
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{
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// ndof1 == ndof2 in this case
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for (int i = 0; i < ndofA; ++i)
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{
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denom1 += jacB[i] * lambdaA[i];
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denom1 += jacA[i] * lambdaB[i];
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}
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}
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btScalar d = denom0+denom1;
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if (btFabs(d)>SIMD_EPSILON)
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{
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constraintRow.m_jacDiagABInv = 1.f/(d);
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} else
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{
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constraintRow.m_jacDiagABInv = 1.f;
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}
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}
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//compute rhs and remaining constraintRow fields
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btScalar rel_vel = 0.f;
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int ndofA = 0;
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int ndofB = 0;
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{
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btVector3 vel1,vel2;
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if (multiBodyA)
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{
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ndofA = multiBodyA->getNumLinks() + 6;
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btScalar* jacA = &data.m_jacobians[constraintRow.m_jacAindex];
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for (int i = 0; i < ndofA ; ++i)
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rel_vel += multiBodyA->getVelocityVector()[i] * jacA[i];
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}
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if (multiBodyB)
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{
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ndofB = multiBodyB->getNumLinks() + 6;
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btScalar* jacB = &data.m_jacobians[constraintRow.m_jacBindex];
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for (int i = 0; i < ndofB ; ++i)
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rel_vel += multiBodyB->getVelocityVector()[i] * jacB[i];
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}
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constraintRow.m_friction = 0.f;
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constraintRow.m_appliedImpulse = 0.f;
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constraintRow.m_appliedPushImpulse = 0.f;
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btScalar velocityError = desiredVelocity - rel_vel;// * damping;
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btScalar erp = infoGlobal.m_erp2;
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btScalar velocityImpulse = velocityError *constraintRow.m_jacDiagABInv;
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if (!infoGlobal.m_splitImpulse)
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{
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//combine position and velocity into rhs
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constraintRow.m_rhs = velocityImpulse;
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constraintRow.m_rhsPenetration = 0.f;
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} else
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{
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//split position and velocity into rhs and m_rhsPenetration
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constraintRow.m_rhs = velocityImpulse;
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constraintRow.m_rhsPenetration = 0.f;
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}
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constraintRow.m_cfm = 0.f;
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constraintRow.m_lowerLimit = lowerLimit;
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constraintRow.m_upperLimit = upperLimit;
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}
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return rel_vel;
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}
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void btMultiBodyConstraint::applyDeltaVee(btMultiBodyJacobianData& data, btScalar* delta_vee, btScalar impulse, int velocityIndex, int ndof)
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{
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for (int i = 0; i < ndof; ++i)
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data.m_deltaVelocities[velocityIndex+i] += delta_vee[i] * impulse;
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}
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void btMultiBodyConstraint::fillMultiBodyConstraintMixed(btMultiBodySolverConstraint& solverConstraint,
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btMultiBodyJacobianData& data,
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const btVector3& contactNormalOnB,
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const btVector3& posAworld, const btVector3& posBworld,
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btScalar position,
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const btContactSolverInfo& infoGlobal,
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btScalar& relaxation,
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bool isFriction, btScalar desiredVelocity, btScalar cfmSlip)
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{
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btVector3 rel_pos1 = posAworld;
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btVector3 rel_pos2 = posBworld;
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solverConstraint.m_multiBodyA = m_bodyA;
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solverConstraint.m_multiBodyB = m_bodyB;
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solverConstraint.m_linkA = m_linkA;
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solverConstraint.m_linkB = m_linkB;
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btMultiBody* multiBodyA = solverConstraint.m_multiBodyA;
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btMultiBody* multiBodyB = solverConstraint.m_multiBodyB;
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const btVector3& pos1 = posAworld;
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const btVector3& pos2 = posBworld;
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btSolverBody* bodyA = multiBodyA ? 0 : &data.m_solverBodyPool->at(solverConstraint.m_solverBodyIdA);
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btSolverBody* bodyB = multiBodyB ? 0 : &data.m_solverBodyPool->at(solverConstraint.m_solverBodyIdB);
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btRigidBody* rb0 = multiBodyA ? 0 : bodyA->m_originalBody;
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btRigidBody* rb1 = multiBodyB ? 0 : bodyB->m_originalBody;
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if (bodyA)
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rel_pos1 = pos1 - bodyA->getWorldTransform().getOrigin();
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if (bodyB)
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rel_pos2 = pos2 - bodyB->getWorldTransform().getOrigin();
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relaxation = 1.f;
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if (multiBodyA)
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{
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const int ndofA = multiBodyA->getNumLinks() + 6;
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solverConstraint.m_deltaVelAindex = multiBodyA->getCompanionId();
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if (solverConstraint.m_deltaVelAindex <0)
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{
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solverConstraint.m_deltaVelAindex = data.m_deltaVelocities.size();
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multiBodyA->setCompanionId(solverConstraint.m_deltaVelAindex);
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data.m_deltaVelocities.resize(data.m_deltaVelocities.size()+ndofA);
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} else
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{
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btAssert(data.m_deltaVelocities.size() >= solverConstraint.m_deltaVelAindex+ndofA);
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}
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solverConstraint.m_jacAindex = data.m_jacobians.size();
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data.m_jacobians.resize(data.m_jacobians.size()+ndofA);
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data.m_deltaVelocitiesUnitImpulse.resize(data.m_deltaVelocitiesUnitImpulse.size()+ndofA);
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btAssert(data.m_jacobians.size() == data.m_deltaVelocitiesUnitImpulse.size());
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btScalar* jac1=&data.m_jacobians[solverConstraint.m_jacAindex];
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multiBodyA->fillContactJacobian(solverConstraint.m_linkA, posAworld, contactNormalOnB, jac1, data.scratch_r, data.scratch_v, data.scratch_m);
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btScalar* delta = &data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacAindex];
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multiBodyA->calcAccelerationDeltas(&data.m_jacobians[solverConstraint.m_jacAindex],delta,data.scratch_r, data.scratch_v);
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} else
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{
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btVector3 torqueAxis0 = rel_pos1.cross(contactNormalOnB);
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solverConstraint.m_angularComponentA = rb0 ? rb0->getInvInertiaTensorWorld()*torqueAxis0*rb0->getAngularFactor() : btVector3(0,0,0);
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solverConstraint.m_relpos1CrossNormal = torqueAxis0;
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solverConstraint.m_contactNormal1 = contactNormalOnB;
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}
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if (multiBodyB)
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{
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const int ndofB = multiBodyB->getNumLinks() + 6;
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solverConstraint.m_deltaVelBindex = multiBodyB->getCompanionId();
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if (solverConstraint.m_deltaVelBindex <0)
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{
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solverConstraint.m_deltaVelBindex = data.m_deltaVelocities.size();
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multiBodyB->setCompanionId(solverConstraint.m_deltaVelBindex);
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data.m_deltaVelocities.resize(data.m_deltaVelocities.size()+ndofB);
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}
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solverConstraint.m_jacBindex = data.m_jacobians.size();
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data.m_jacobians.resize(data.m_jacobians.size()+ndofB);
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data.m_deltaVelocitiesUnitImpulse.resize(data.m_deltaVelocitiesUnitImpulse.size()+ndofB);
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btAssert(data.m_jacobians.size() == data.m_deltaVelocitiesUnitImpulse.size());
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multiBodyB->fillContactJacobian(solverConstraint.m_linkB, posBworld, -contactNormalOnB, &data.m_jacobians[solverConstraint.m_jacBindex], data.scratch_r, data.scratch_v, data.scratch_m);
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multiBodyB->calcAccelerationDeltas(&data.m_jacobians[solverConstraint.m_jacBindex],&data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacBindex],data.scratch_r, data.scratch_v);
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} else
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{
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btVector3 torqueAxis1 = rel_pos2.cross(contactNormalOnB);
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solverConstraint.m_angularComponentB = rb1 ? rb1->getInvInertiaTensorWorld()*-torqueAxis1*rb1->getAngularFactor() : btVector3(0,0,0);
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solverConstraint.m_relpos2CrossNormal = -torqueAxis1;
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solverConstraint.m_contactNormal2 = -contactNormalOnB;
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}
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{
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btVector3 vec;
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btScalar denom0 = 0.f;
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btScalar denom1 = 0.f;
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btScalar* jacB = 0;
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btScalar* jacA = 0;
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btScalar* lambdaA =0;
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btScalar* lambdaB =0;
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int ndofA = 0;
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if (multiBodyA)
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{
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ndofA = multiBodyA->getNumLinks() + 6;
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jacA = &data.m_jacobians[solverConstraint.m_jacAindex];
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lambdaA = &data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacAindex];
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for (int i = 0; i < ndofA; ++i)
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{
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btScalar j = jacA[i] ;
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btScalar l =lambdaA[i];
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denom0 += j*l;
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}
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} else
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{
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if (rb0)
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{
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vec = ( solverConstraint.m_angularComponentA).cross(rel_pos1);
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denom0 = rb0->getInvMass() + contactNormalOnB.dot(vec);
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}
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}
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if (multiBodyB)
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{
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const int ndofB = multiBodyB->getNumLinks() + 6;
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jacB = &data.m_jacobians[solverConstraint.m_jacBindex];
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lambdaB = &data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacBindex];
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for (int i = 0; i < ndofB; ++i)
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{
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btScalar j = jacB[i] ;
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btScalar l =lambdaB[i];
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denom1 += j*l;
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}
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} else
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{
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if (rb1)
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{
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vec = ( -solverConstraint.m_angularComponentB).cross(rel_pos2);
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denom1 = rb1->getInvMass() + contactNormalOnB.dot(vec);
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}
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}
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if (multiBodyA && (multiBodyA==multiBodyB))
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{
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// ndof1 == ndof2 in this case
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for (int i = 0; i < ndofA; ++i)
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{
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denom1 += jacB[i] * lambdaA[i];
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denom1 += jacA[i] * lambdaB[i];
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}
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}
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btScalar d = denom0+denom1;
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if (btFabs(d)>SIMD_EPSILON)
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{
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solverConstraint.m_jacDiagABInv = relaxation/(d);
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} else
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{
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solverConstraint.m_jacDiagABInv = 1.f;
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}
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}
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//compute rhs and remaining solverConstraint fields
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btScalar restitution = 0.f;
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btScalar penetration = isFriction? 0 : position+infoGlobal.m_linearSlop;
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btScalar rel_vel = 0.f;
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int ndofA = 0;
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int ndofB = 0;
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{
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btVector3 vel1,vel2;
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if (multiBodyA)
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{
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ndofA = multiBodyA->getNumLinks() + 6;
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btScalar* jacA = &data.m_jacobians[solverConstraint.m_jacAindex];
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for (int i = 0; i < ndofA ; ++i)
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rel_vel += multiBodyA->getVelocityVector()[i] * jacA[i];
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} else
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{
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if (rb0)
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{
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rel_vel += rb0->getVelocityInLocalPoint(rel_pos1).dot(solverConstraint.m_contactNormal1);
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}
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}
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if (multiBodyB)
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{
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ndofB = multiBodyB->getNumLinks() + 6;
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btScalar* jacB = &data.m_jacobians[solverConstraint.m_jacBindex];
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for (int i = 0; i < ndofB ; ++i)
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rel_vel += multiBodyB->getVelocityVector()[i] * jacB[i];
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} else
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{
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if (rb1)
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{
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rel_vel += rb1->getVelocityInLocalPoint(rel_pos2).dot(solverConstraint.m_contactNormal2);
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}
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}
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solverConstraint.m_friction = 0.f;//cp.m_combinedFriction;
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restitution = restitution * -rel_vel;//restitutionCurve(rel_vel, cp.m_combinedRestitution);
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if (restitution <= btScalar(0.))
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{
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restitution = 0.f;
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};
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}
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///warm starting (or zero if disabled)
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/*
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if (infoGlobal.m_solverMode & SOLVER_USE_WARMSTARTING)
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{
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solverConstraint.m_appliedImpulse = isFriction ? 0 : cp.m_appliedImpulse * infoGlobal.m_warmstartingFactor;
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if (solverConstraint.m_appliedImpulse)
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{
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if (multiBodyA)
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{
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btScalar impulse = solverConstraint.m_appliedImpulse;
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btScalar* deltaV = &data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacAindex];
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multiBodyA->applyDeltaVee(deltaV,impulse);
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applyDeltaVee(data,deltaV,impulse,solverConstraint.m_deltaVelAindex,ndofA);
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} else
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{
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if (rb0)
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bodyA->internalApplyImpulse(solverConstraint.m_contactNormal1*bodyA->internalGetInvMass()*rb0->getLinearFactor(),solverConstraint.m_angularComponentA,solverConstraint.m_appliedImpulse);
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}
|
|
if (multiBodyB)
|
|
{
|
|
btScalar impulse = solverConstraint.m_appliedImpulse;
|
|
btScalar* deltaV = &data.m_deltaVelocitiesUnitImpulse[solverConstraint.m_jacBindex];
|
|
multiBodyB->applyDeltaVee(deltaV,impulse);
|
|
applyDeltaVee(data,deltaV,impulse,solverConstraint.m_deltaVelBindex,ndofB);
|
|
} else
|
|
{
|
|
if (rb1)
|
|
bodyB->internalApplyImpulse(-solverConstraint.m_contactNormal2*bodyB->internalGetInvMass()*rb1->getLinearFactor(),-solverConstraint.m_angularComponentB,-(btScalar)solverConstraint.m_appliedImpulse);
|
|
}
|
|
}
|
|
} else
|
|
*/
|
|
{
|
|
solverConstraint.m_appliedImpulse = 0.f;
|
|
}
|
|
|
|
solverConstraint.m_appliedPushImpulse = 0.f;
|
|
|
|
{
|
|
|
|
|
|
btScalar positionalError = 0.f;
|
|
btScalar velocityError = restitution - rel_vel;// * damping;
|
|
|
|
|
|
btScalar erp = infoGlobal.m_erp2;
|
|
if (!infoGlobal.m_splitImpulse || (penetration > infoGlobal.m_splitImpulsePenetrationThreshold))
|
|
{
|
|
erp = infoGlobal.m_erp;
|
|
}
|
|
|
|
if (penetration>0)
|
|
{
|
|
positionalError = 0;
|
|
velocityError = -penetration / infoGlobal.m_timeStep;
|
|
|
|
} else
|
|
{
|
|
positionalError = -penetration * erp/infoGlobal.m_timeStep;
|
|
}
|
|
|
|
btScalar penetrationImpulse = positionalError*solverConstraint.m_jacDiagABInv;
|
|
btScalar velocityImpulse = velocityError *solverConstraint.m_jacDiagABInv;
|
|
|
|
if (!infoGlobal.m_splitImpulse || (penetration > infoGlobal.m_splitImpulsePenetrationThreshold))
|
|
{
|
|
//combine position and velocity into rhs
|
|
solverConstraint.m_rhs = penetrationImpulse+velocityImpulse;
|
|
solverConstraint.m_rhsPenetration = 0.f;
|
|
|
|
} else
|
|
{
|
|
//split position and velocity into rhs and m_rhsPenetration
|
|
solverConstraint.m_rhs = velocityImpulse;
|
|
solverConstraint.m_rhsPenetration = penetrationImpulse;
|
|
}
|
|
|
|
solverConstraint.m_cfm = 0.f;
|
|
solverConstraint.m_lowerLimit = -m_maxAppliedImpulse;
|
|
solverConstraint.m_upperLimit = m_maxAppliedImpulse;
|
|
}
|
|
|
|
}
|