void btSliderConstraint::getInfo1(btConstraintInfo1* info)
{
if (m_useSolveConstraintObsolete)
{
info->m_numConstraintRows = 0;
info->nub = 0;
}
else
{
info->m_numConstraintRows = 4; // Fixed 2 linear + 2 angular
info->nub = 2;
//prepare constraint
calculateTransforms();
testLinLimits();
if(getSolveLinLimit() || getPoweredLinMotor())
{
info->m_numConstraintRows++; // limit 3rd linear as well
info->nub--;
}
testAngLimits();
if(getSolveAngLimit() || getPoweredAngMotor())
{
info->m_numConstraintRows++; // limit 3rd angular as well
info->nub--;
}
}
}
bool SliderJointSW::setup(float p_step)
{
//calculate transforms
m_calculatedTransformA = A->get_transform() * m_frameInA;
m_calculatedTransformB = B->get_transform() * m_frameInB;
m_realPivotAInW = m_calculatedTransformA.origin;
m_realPivotBInW = m_calculatedTransformB.origin;
m_sliderAxis = m_calculatedTransformA.basis.get_axis(0); // along X
m_delta = m_realPivotBInW - m_realPivotAInW;
m_projPivotInW = m_realPivotAInW + m_sliderAxis.dot(m_delta) * m_sliderAxis;
m_relPosA = m_projPivotInW - A->get_transform().origin;
m_relPosB = m_realPivotBInW - B->get_transform().origin;
Vector3 normalWorld;
int i;
//linear part
for(i = 0; i < 3; i++)
{
normalWorld = m_calculatedTransformA.basis.get_axis(i);
memnew_placement(&m_jacLin[i], JacobianEntrySW(
A->get_transform().basis.transposed(),
B->get_transform().basis.transposed(),
m_relPosA,
m_relPosB,
normalWorld,
A->get_inv_inertia(),
A->get_inv_mass(),
B->get_inv_inertia(),
B->get_inv_mass()
));
m_jacLinDiagABInv[i] = real_t(1.) / m_jacLin[i].getDiagonal();
m_depth[i] = m_delta.dot(normalWorld);
}
testLinLimits();
// angular part
for(i = 0; i < 3; i++)
{
normalWorld = m_calculatedTransformA.basis.get_axis(i);
memnew_placement(&m_jacAng[i], JacobianEntrySW(
normalWorld,
A->get_transform().basis.transposed(),
B->get_transform().basis.transposed(),
A->get_inv_inertia(),
B->get_inv_inertia()
));
}
testAngLimits();
Vector3 axisA = m_calculatedTransformA.basis.get_axis(0);
m_kAngle = real_t(1.0 )/ (A->compute_angular_impulse_denominator(axisA) + B->compute_angular_impulse_denominator(axisA));
// clear accumulator for motors
m_accumulatedLinMotorImpulse = real_t(0.0);
m_accumulatedAngMotorImpulse = real_t(0.0);
return true;
} // SliderJointSW::buildJacobianInt()
void btSliderConstraint::buildJacobianInt(btRigidBody& rbA, btRigidBody& rbB, const btTransform& frameInA, const btTransform& frameInB)
{
//calculate transforms
m_calculatedTransformA = rbA.getCenterOfMassTransform() * frameInA;
m_calculatedTransformB = rbB.getCenterOfMassTransform() * frameInB;
m_realPivotAInW = m_calculatedTransformA.getOrigin();
m_realPivotBInW = m_calculatedTransformB.getOrigin();
m_sliderAxis = m_calculatedTransformA.getBasis().getColumn(0); // along X
m_delta = m_realPivotBInW - m_realPivotAInW;
m_projPivotInW = m_realPivotAInW + m_sliderAxis.dot(m_delta) * m_sliderAxis;
m_relPosA = m_projPivotInW - rbA.getCenterOfMassPosition();
m_relPosB = m_realPivotBInW - rbB.getCenterOfMassPosition();
btVector3 normalWorld;
int i;
//linear part
for(i = 0; i < 3; i++)
{
normalWorld = m_calculatedTransformA.getBasis().getColumn(i);
new (&m_jacLin[i]) btJacobianEntry(
rbA.getCenterOfMassTransform().getBasis().transpose(),
rbB.getCenterOfMassTransform().getBasis().transpose(),
m_relPosA,
m_relPosB,
normalWorld,
rbA.getInvInertiaDiagLocal(),
rbA.getInvMass(),
rbB.getInvInertiaDiagLocal(),
rbB.getInvMass()
);
m_jacLinDiagABInv[i] = btScalar(1.) / m_jacLin[i].getDiagonal();
m_depth[i] = m_delta.dot(normalWorld);
}
testLinLimits();
// angular part
for(i = 0; i < 3; i++)
{
normalWorld = m_calculatedTransformA.getBasis().getColumn(i);
new (&m_jacAng[i]) btJacobianEntry(
normalWorld,
rbA.getCenterOfMassTransform().getBasis().transpose(),
rbB.getCenterOfMassTransform().getBasis().transpose(),
rbA.getInvInertiaDiagLocal(),
rbB.getInvInertiaDiagLocal()
);
}
testAngLimits();
btVector3 axisA = m_calculatedTransformA.getBasis().getColumn(0);
m_kAngle = btScalar(1.0 )/ (rbA.computeAngularImpulseDenominator(axisA) + rbB.computeAngularImpulseDenominator(axisA));
// clear accumulator for motors
m_accumulatedLinMotorImpulse = btScalar(0.0);
m_accumulatedAngMotorImpulse = btScalar(0.0);
}
