btScalar btMultiBodyConstraintSolver::solveSingleIteration(int iteration, btCollisionObject** bodies ,int numBodies,btPersistentManifold** manifoldPtr, int numManifolds,btTypedConstraint** constraints,int numConstraints,const btContactSolverInfo& infoGlobal,btIDebugDraw* debugDrawer)
{
btScalar val = btSequentialImpulseConstraintSolver::solveSingleIteration(iteration, bodies ,numBodies,manifoldPtr, numManifolds,constraints,numConstraints,infoGlobal,debugDrawer);
//solve featherstone non-contact constraints
//printf("m_multiBodyNonContactConstraints = %d\n",m_multiBodyNonContactConstraints.size());
for (int j=0;j<m_multiBodyNonContactConstraints.size();j++)
{
btMultiBodySolverConstraint& constraint = m_multiBodyNonContactConstraints[j];
//if (iteration < constraint.m_overrideNumSolverIterations)
//resolveSingleConstraintRowGenericMultiBody(constraint);
resolveSingleConstraintRowGeneric(constraint);
if(constraint.m_multiBodyA)
constraint.m_multiBodyA->setPosUpdated(false);
if(constraint.m_multiBodyB)
constraint.m_multiBodyB->setPosUpdated(false);
}
//solve featherstone normal contact
for (int j=0;j<m_multiBodyNormalContactConstraints.size();j++)
{
btMultiBodySolverConstraint& constraint = m_multiBodyNormalContactConstraints[j];
if (iteration < infoGlobal.m_numIterations)
resolveSingleConstraintRowGeneric(constraint);
if(constraint.m_multiBodyA)
constraint.m_multiBodyA->setPosUpdated(false);
if(constraint.m_multiBodyB)
constraint.m_multiBodyB->setPosUpdated(false);
}
//solve featherstone frictional contact
for (int j=0;j<this->m_multiBodyFrictionContactConstraints.size();j++)
{
if (iteration < infoGlobal.m_numIterations)
{
btMultiBodySolverConstraint& frictionConstraint = m_multiBodyFrictionContactConstraints[j];
btScalar totalImpulse = m_multiBodyNormalContactConstraints[frictionConstraint.m_frictionIndex].m_appliedImpulse;
//adjust friction limits here
if (totalImpulse>btScalar(0))
{
frictionConstraint.m_lowerLimit = -(frictionConstraint.m_friction*totalImpulse);
frictionConstraint.m_upperLimit = frictionConstraint.m_friction*totalImpulse;
resolveSingleConstraintRowGeneric(frictionConstraint);
if(frictionConstraint.m_multiBodyA)
frictionConstraint.m_multiBodyA->setPosUpdated(false);
if(frictionConstraint.m_multiBodyB)
frictionConstraint.m_multiBodyB->setPosUpdated(false);
}
}
}
return val;
}
// Project Gauss Seidel or the equivalent Sequential Impulse
void btSequentialImpulseConstraintSolver::resolveSingleConstraintRowGenericSIMD(btSolverBody& body1,btSolverBody& body2,const btSolverConstraint& c)
{
#ifdef USE_SIMD
__m128 cpAppliedImp = _mm_set1_ps(c.m_appliedImpulse);
__m128 lowerLimit1 = _mm_set1_ps(c.m_lowerLimit);
__m128 upperLimit1 = _mm_set1_ps(c.m_upperLimit);
__m128 deltaImpulse = _mm_sub_ps(_mm_set1_ps(c.m_rhs), _mm_mul_ps(_mm_set1_ps(c.m_appliedImpulse),_mm_set1_ps(c.m_cfm)));
__m128 deltaVel1Dotn = _mm_add_ps(_vmathVfDot3(c.m_contactNormal.mVec128,body1.m_deltaLinearVelocity.mVec128), _vmathVfDot3(c.m_relpos1CrossNormal.mVec128,body1.m_deltaAngularVelocity.mVec128));
__m128 deltaVel2Dotn = _mm_sub_ps(_vmathVfDot3(c.m_relpos2CrossNormal.mVec128,body2.m_deltaAngularVelocity.mVec128),_vmathVfDot3((c.m_contactNormal).mVec128,body2.m_deltaLinearVelocity.mVec128));
deltaImpulse = _mm_sub_ps(deltaImpulse,_mm_mul_ps(deltaVel1Dotn,_mm_set1_ps(c.m_jacDiagABInv)));
deltaImpulse = _mm_sub_ps(deltaImpulse,_mm_mul_ps(deltaVel2Dotn,_mm_set1_ps(c.m_jacDiagABInv)));
btSimdScalar sum = _mm_add_ps(cpAppliedImp,deltaImpulse);
btSimdScalar resultLowerLess,resultUpperLess;
resultLowerLess = _mm_cmplt_ps(sum,lowerLimit1);
resultUpperLess = _mm_cmplt_ps(sum,upperLimit1);
__m128 lowMinApplied = _mm_sub_ps(lowerLimit1,cpAppliedImp);
deltaImpulse = _mm_or_ps( _mm_and_ps(resultLowerLess, lowMinApplied), _mm_andnot_ps(resultLowerLess, deltaImpulse) );
c.m_appliedImpulse = _mm_or_ps( _mm_and_ps(resultLowerLess, lowerLimit1), _mm_andnot_ps(resultLowerLess, sum) );
__m128 upperMinApplied = _mm_sub_ps(upperLimit1,cpAppliedImp);
deltaImpulse = _mm_or_ps( _mm_and_ps(resultUpperLess, deltaImpulse), _mm_andnot_ps(resultUpperLess, upperMinApplied) );
c.m_appliedImpulse = _mm_or_ps( _mm_and_ps(resultUpperLess, c.m_appliedImpulse), _mm_andnot_ps(resultUpperLess, upperLimit1) );
__m128 linearComponentA = _mm_mul_ps(c.m_contactNormal.mVec128,body1.m_invMass.mVec128);
__m128 linearComponentB = _mm_mul_ps((c.m_contactNormal).mVec128,body2.m_invMass.mVec128);
__m128 impulseMagnitude = deltaImpulse;
body1.m_deltaLinearVelocity.mVec128 = _mm_add_ps(body1.m_deltaLinearVelocity.mVec128,_mm_mul_ps(linearComponentA,impulseMagnitude));
body1.m_deltaAngularVelocity.mVec128 = _mm_add_ps(body1.m_deltaAngularVelocity.mVec128 ,_mm_mul_ps(c.m_angularComponentA.mVec128,impulseMagnitude));
body2.m_deltaLinearVelocity.mVec128 = _mm_sub_ps(body2.m_deltaLinearVelocity.mVec128,_mm_mul_ps(linearComponentB,impulseMagnitude));
body2.m_deltaAngularVelocity.mVec128 = _mm_add_ps(body2.m_deltaAngularVelocity.mVec128 ,_mm_mul_ps(c.m_angularComponentB.mVec128,impulseMagnitude));
#else
resolveSingleConstraintRowGeneric(body1,body2,c);
#endif
}