public float SolveLinearAxis(
float timeStep,
float jacDiagABInv,
RigidBody body1, ref Vector3 pointInA,
RigidBody body2, ref Vector3 pointInB,
int limit_index,
ref Vector3 axis_normal_on_a,
ref Vector3 anchorPos)
{
///find relative velocity
// Vector3 rel_pos1 = pointInA - body1.getCenterOfMassPosition();
// Vector3 rel_pos2 = pointInB - body2.getCenterOfMassPosition();
Vector3 rel_pos1 = anchorPos - body1.GetCenterOfMassPosition();
Vector3 rel_pos2 = anchorPos - body2.GetCenterOfMassPosition();
Vector3 vel1 = Vector3.Zero;
body1.InternalGetVelocityInLocalPointObsolete(ref rel_pos1,ref vel1);
Vector3 vel2 = Vector3.Zero;;
body2.InternalGetVelocityInLocalPointObsolete(ref rel_pos2,ref vel2);
Vector3 vel = vel1 - vel2;
float rel_vel = Vector3.Dot(axis_normal_on_a,vel);
/// apply displacement correction
//positional error (zeroth order error)
float depth = -Vector3.Dot((pointInA - pointInB),axis_normal_on_a);
float lo = float.MinValue;
float hi = float.MaxValue;
float minLimit = MathUtil.VectorComponent(ref m_lowerLimit,limit_index);
float maxLimit = MathUtil.VectorComponent(ref m_upperLimit,limit_index);
//handle the limits
if (minLimit < maxLimit)
{
{
if (depth > maxLimit)
{
depth -= maxLimit;
lo = 0f;
}
else
{
if (depth < minLimit)
{
depth -= minLimit;
hi = 0f;
}
else
{
return 0.0f;
}
}
}
}
float normalImpulse= m_limitSoftness*(m_restitution*depth/timeStep - m_damping*rel_vel) * jacDiagABInv;
float oldNormalImpulse = MathUtil.VectorComponent(ref m_accumulatedImpulse,limit_index);
float sum = oldNormalImpulse + normalImpulse;
MathUtil.VectorComponent(ref m_accumulatedImpulse,limit_index,(sum > hi ? 0f: sum < lo ? 0f : sum));
normalImpulse = MathUtil.VectorComponent(ref m_accumulatedImpulse,limit_index) - oldNormalImpulse;
Vector3 impulse_vector = axis_normal_on_a * normalImpulse;
//body1.applyImpulse( impulse_vector, rel_pos1);
//body2.applyImpulse(-impulse_vector, rel_pos2);
Vector3 ftorqueAxis1 = Vector3.Cross(rel_pos1,axis_normal_on_a);
Vector3 ftorqueAxis2 = Vector3.Cross(rel_pos2,axis_normal_on_a);
body1.InternalApplyImpulse(axis_normal_on_a*body1.GetInvMass(), Vector3.TransformNormal(ftorqueAxis1,body1.GetInvInertiaTensorWorld()),normalImpulse);
body2.InternalApplyImpulse(axis_normal_on_a * body2.GetInvMass(), Vector3.TransformNormal(ftorqueAxis2,body2.GetInvInertiaTensorWorld()), -normalImpulse);
return normalImpulse;
}
