public override void AddContact(Contact contact)
{
var penetrationConstraint = penetrationConstraintPool.Pop();
penetrationConstraint.Setup(this, contact);
penetrationConstraints.Add(penetrationConstraint);
if (!twistFriction.isActive)
{
//This is the first real contact. All constraints need to become active.
twistFriction.Setup(this);
slidingFriction.Setup(this);
}
}