internal void setFrictionConstraintImpulse( btSolverConstraint solverConstraint,
btSolverBody bodyA, btSolverBody bodyB,
btManifoldPoint cp, btContactSolverInfo infoGlobal )
{
btRigidBody rb0 = bodyA.m_originalBody;
btRigidBody rb1 = bodyB.m_originalBody;
{
btSolverConstraint frictionConstraint1 = m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex];
if( ( infoGlobal.m_solverMode & btSolverMode.SOLVER_USE_WARMSTARTING ) != 0 )
{
frictionConstraint1.m_appliedImpulse = cp.m_appliedImpulseLateral1 * infoGlobal.m_warmstartingFactor;
btScalar.Dbg( "New Applied source is " + cp.m_appliedImpulseLateral1.ToString( "g17" ) );
if( rb0 != null )
{
btVector3 tmp; frictionConstraint1.m_contactNormal1.Mult2( ref rb0.m_linearFactor, rb0.getInvMass(), out tmp );
bodyA.applyImpulse( ref tmp, ref frictionConstraint1.m_angularComponentA, frictionConstraint1.m_appliedImpulse );
}
if( rb1 != null )
{
btVector3 tmp; frictionConstraint1.m_contactNormal2.Mult2( ref rb1.m_linearFactor, -rb1.getInvMass(), out tmp );
btVector3 tmp2; frictionConstraint1.m_angularComponentB.Invert( out tmp2 );
bodyB.applyImpulse( ref tmp, ref tmp2, -(double)frictionConstraint1.m_appliedImpulse );
}
}
else
{
frictionConstraint1.m_appliedImpulse = 0;
}
}
if( ( infoGlobal.m_solverMode & btSolverMode.SOLVER_USE_2_FRICTION_DIRECTIONS ) != 0 )
{
btSolverConstraint frictionConstraint2 = m_tmpSolverContactFrictionConstraintPool[solverConstraint.m_frictionIndex + 1];
if( ( infoGlobal.m_solverMode & btSolverMode.SOLVER_USE_WARMSTARTING ) != 0 )
{
frictionConstraint2.m_appliedImpulse = cp.m_appliedImpulseLateral2 * infoGlobal.m_warmstartingFactor;
if( rb0 != null )
{
btVector3 tmp; frictionConstraint2.m_contactNormal1.Mult( rb0.getInvMass(), out tmp );
bodyA.applyImpulse( ref tmp, ref frictionConstraint2.m_angularComponentA, frictionConstraint2.m_appliedImpulse );
}
if( rb1 != null )
{
btVector3 tmp; frictionConstraint2.m_contactNormal2.Mult( -rb1.getInvMass(), out tmp );
btVector3 tmp2; frictionConstraint2.m_angularComponentB.Invert( out tmp2 );
bodyB.applyImpulse( ref tmp, ref tmp2, -(double)frictionConstraint2.m_appliedImpulse );
}
}
else
{
frictionConstraint2.m_appliedImpulse = 0;
}
}
}
///This is the scalar reference implementation of solving a single constraint row, the innerloop of the Projected Gauss Seidel/Sequential Impulse constraint solver
///Below are optional SSE2 and SSE4/FMA3 versions. We assume most hardware has SSE2. For SSE4/FMA3 we perform a CPU feature check.
public static double gResolveSingleConstraintRowGeneric_scalar_reference( btSolverBody body1, btSolverBody body2, btSolverConstraint c )
{
double deltaImpulse = c.m_rhs - (double)( c.m_appliedImpulse ) * c.m_cfm;
double deltaVel1Dotn = c.m_contactNormal1.dot( ref body1.m_deltaLinearVelocity )
+ c.m_relpos1CrossNormal.dot( ref body1.m_deltaAngularVelocity );
double deltaVel2Dotn = c.m_contactNormal2.dot( ref body2.m_deltaLinearVelocity )
+ c.m_relpos2CrossNormal.dot( ref body2.m_deltaAngularVelocity );
// double delta_rel_vel = deltaVel1Dotn-deltaVel2Dotn;
deltaImpulse -= deltaVel1Dotn * c.m_jacDiagABInv;
deltaImpulse -= deltaVel2Dotn * c.m_jacDiagABInv;
double sum = (double)( c.m_appliedImpulse ) + deltaImpulse;
if( sum < c.m_lowerLimit )
{
deltaImpulse = c.m_lowerLimit - c.m_appliedImpulse;
c.m_appliedImpulse = c.m_lowerLimit;
}
else if( sum > c.m_upperLimit )
{
deltaImpulse = c.m_upperLimit - c.m_appliedImpulse;
c.m_appliedImpulse = c.m_upperLimit;
}
else
{
c.m_appliedImpulse = sum;
}
btScalar.Dbg( "Constraint applied impulse is " + c.m_appliedImpulse.ToString( "g17" ) );
btVector3 mass, val;
body1.internalGetInvMass( out mass );
mass.Mult( ref c.m_contactNormal1, out val );
body1.applyImpulse( ref val, ref c.m_angularComponentA, deltaImpulse );
body2.internalGetInvMass( out mass );
mass.Mult( ref c.m_contactNormal2, out val );
body2.applyImpulse( ref val, ref c.m_angularComponentB, deltaImpulse );
return deltaImpulse;
}
internal void setupContactConstraint( btSolverConstraint solverConstraint,
btSolverBody bodyA, btSolverBody bodyB,
btManifoldPoint cp, btContactSolverInfo infoGlobal,
out double relaxation,
ref btVector3 rel_pos1, ref btVector3 rel_pos2 )
{
// ref btVector3 pos1 = cp.getPositionWorldOnA();
// ref btVector3 pos2 = cp.getPositionWorldOnB();
btRigidBody rb0 = bodyA.m_originalBody;
btRigidBody rb1 = bodyB.m_originalBody;
// btVector3 rel_pos1 = pos1 - colObj0.getWorldTransform().getOrigin();
// btVector3 rel_pos2 = pos2 - colObj1.getWorldTransform().getOrigin();
//rel_pos1 = pos1 - bodyA.getWorldTransform().getOrigin();
//rel_pos2 = pos2 - bodyB.getWorldTransform().getOrigin();
relaxation = 1;
btVector3 torqueAxis0; rel_pos1.cross( ref cp.m_normalWorldOnB, out torqueAxis0 );
btVector3 tmp;
//solverConstraint.m_angularComponentA = rb0 != null ? rb0.m_invInertiaTensorWorld * torqueAxis0 * rb0.getAngularFactor() : btVector3.Zero;
if( rb0 != null )
{
rb0.m_invInertiaTensorWorld.Apply( ref torqueAxis0, out tmp );
tmp.Mult( ref rb0.m_angularFactor, out solverConstraint.m_angularComponentA );
}
else
solverConstraint.m_angularComponentA = btVector3.Zero;
btVector3 torqueAxis1; rel_pos2.cross( ref cp.m_normalWorldOnB, out torqueAxis1 );
torqueAxis1.Invert( out torqueAxis1 );
//solverConstraint.m_angularComponentB = rb1 != null ? rb1.m_invInertiaTensorWorld * -torqueAxis1 * rb1.getAngularFactor() : btVector3.Zero;
if( rb1 != null )
{
rb1.m_invInertiaTensorWorld.Apply( ref torqueAxis1, out tmp );
tmp.Mult( ref rb1.m_angularFactor, out solverConstraint.m_angularComponentB );
}
else
solverConstraint.m_angularComponentB = btVector3.Zero;
{
#if COMPUTE_IMPULSE_DENOM
double denom0 = rb0.computeImpulseDenominator(pos1,cp.m_normalWorldOnB);
double denom1 = rb1.computeImpulseDenominator(pos2,cp.m_normalWorldOnB);
#else
btVector3 vec;
double denom0 = 0;
double denom1 = 0;
if( rb0 != null )
{
( solverConstraint.m_angularComponentA ).cross( ref rel_pos1, out vec );
denom0 = rb0.getInvMass() + cp.m_normalWorldOnB.dot( vec );
}
if( rb1 != null )
{
solverConstraint.m_angularComponentB.Invert( out tmp );
tmp.cross( ref rel_pos2, out vec );
denom1 = rb1.getInvMass() + cp.m_normalWorldOnB.dot( vec );
}
#endif //COMPUTE_IMPULSE_DENOM
double denom = relaxation / ( denom0 + denom1 );
btScalar.Dbg( "m_jacDiagABInv 3 set to " + denom.ToString( "g17" ) );
solverConstraint.m_jacDiagABInv = denom;
}
if( rb0 != null )
{
solverConstraint.m_contactNormal1 = cp.m_normalWorldOnB;
solverConstraint.m_relpos1CrossNormal = torqueAxis0;
btScalar.Dbg( "Torque Axis to relpos1 " + torqueAxis0 );
}
else
{
solverConstraint.m_contactNormal1 = btVector3.Zero;
solverConstraint.m_relpos1CrossNormal = btVector3.Zero;
}
if( rb1 != null )
{
cp.m_normalWorldOnB.Invert( out solverConstraint.m_contactNormal2 );
solverConstraint.m_relpos2CrossNormal = torqueAxis1;
btScalar.Dbg( "Torque Axis to relpos2 " + torqueAxis1 );
}
else
{
solverConstraint.m_contactNormal2 = btVector3.Zero;
solverConstraint.m_relpos2CrossNormal = btVector3.Zero;
}
double restitution = 0;
double penetration = cp.getDistance() + infoGlobal.m_linearSlop;
{
btVector3 vel1, vel2;
vel1 = rb0 != null ? rb0.getVelocityInLocalPoint( ref rel_pos1 ) : btVector3.Zero;
vel2 = rb1 != null ? rb1.getVelocityInLocalPoint( ref rel_pos2 ) : btVector3.Zero;
// btVector3 vel2 = rb1 ? rb1.getVelocityInLocalPoint(rel_pos2) : btVector3(0,0,0);
btVector3 vel; vel1.Sub( ref vel2, out vel );
double rel_vel = cp.m_normalWorldOnB.dot( ref vel );
solverConstraint.m_friction = cp.m_combinedFriction;
restitution = restitutionCurve( rel_vel, cp.m_combinedRestitution );
if( restitution <= btScalar.BT_ZERO )
{
restitution = 0;
};
}
///warm starting (or zero if disabled)
if( ( infoGlobal.m_solverMode & btSolverMode.SOLVER_USE_WARMSTARTING ) != 0 )
{
solverConstraint.m_appliedImpulse = cp.m_appliedImpulse * infoGlobal.m_warmstartingFactor;
if( rb0 != null )
{
solverConstraint.m_contactNormal1.Mult2( ref bodyA.m_invMass, ref rb0.m_linearFactor, out tmp );
bodyA.applyImpulse( ref tmp, ref solverConstraint.m_angularComponentA, solverConstraint.m_appliedImpulse );
}
if( rb1 != null )
{
solverConstraint.m_contactNormal2.Mult2( ref rb1.m_linearFactor, ref bodyB.m_invMass, out tmp );
tmp.Invert( out tmp );
btVector3 tmp2; solverConstraint.m_angularComponentB.Invert( out tmp2 );
bodyB.applyImpulse( ref tmp, ref tmp2, -(double)solverConstraint.m_appliedImpulse );
}
}
else
{
solverConstraint.m_appliedImpulse = 0;
}
solverConstraint.m_appliedPushImpulse = 0;
{
btVector3 externalForceImpulseA = bodyA.m_originalBody != null ? bodyA.m_externalForceImpulse : btVector3.Zero;
btVector3 externalTorqueImpulseA = bodyA.m_originalBody != null ? bodyA.m_externalTorqueImpulse : btVector3.Zero;
btVector3 externalForceImpulseB = bodyB.m_originalBody != null ? bodyB.m_externalForceImpulse : btVector3.Zero;
btVector3 externalTorqueImpulseB = bodyB.m_originalBody != null ? bodyB.m_externalTorqueImpulse : btVector3.Zero;
btScalar.Dbg( "external torque impulses " + externalTorqueImpulseA + externalTorqueImpulseB );
double vel1Dotn = solverConstraint.m_contactNormal1.dotAdded( ref bodyA.m_linearVelocity, ref externalForceImpulseA )
+ solverConstraint.m_relpos1CrossNormal.dotAdded( ref bodyA.m_angularVelocity, ref externalTorqueImpulseA );
double vel2Dotn = solverConstraint.m_contactNormal2.dotAdded( ref bodyB.m_linearVelocity, ref externalForceImpulseB )
+ solverConstraint.m_relpos2CrossNormal.dotAdded( ref bodyB.m_angularVelocity, ref externalTorqueImpulseB );
double rel_vel = vel1Dotn + vel2Dotn;
double positionalError = 0;
double velocityError = restitution - rel_vel;// * damping;
double 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;
}
double penetrationImpulse = positionalError * solverConstraint.m_jacDiagABInv;
double 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_contactNormal1.dot(bodyA.m_externalForce*bodyA.m_invMass-bodyB.m_externalForce/bodyB.m_invMass)*solverConstraint.m_jacDiagABInv;
btScalar.Dbg( "Constraint 3 m_rhs " + solverConstraint.m_rhs.ToString( "g17" ) );
solverConstraint.m_rhsPenetration = 0;
}
else
{
//split position and velocity into rhs and m_rhsPenetration
solverConstraint.m_rhs = velocityImpulse;
btScalar.Dbg( "Constraint 4 m_rhs " + solverConstraint.m_rhs.ToString( "g17" ) );
solverConstraint.m_rhsPenetration = penetrationImpulse;
}
solverConstraint.m_cfm = 0;
solverConstraint.m_lowerLimit = 0;
solverConstraint.m_upperLimit = 1e10f;
}
}