///<summary>
/// Removes a contact from the constraint.
///</summary>
///<param name="contact">Contact to remove.</param>
public override void RemoveContact(Contact contact)
{
ContactPenetrationConstraint penetrationConstraint = null;
for (int i = 0; i < penetrationConstraints.Count; i++)
{
if ((penetrationConstraint = penetrationConstraints.Elements[i]).contact == contact)
{
penetrationConstraint.CleanUp();
penetrationConstraints.RemoveAt(i);
penetrationConstraintPool.Push(penetrationConstraint);
break;
}
}
for (int i = frictionConstraints.Count - 1; i >= 0; i--)
{
ContactFrictionConstraint frictionConstraint = frictionConstraints[i];
if (frictionConstraint.PenetrationConstraint == penetrationConstraint)
{
frictionConstraint.CleanUp();
frictionConstraints.RemoveAt(i);
frictionConstraintPool.Push(frictionConstraint);
break;
}
}
}
//TODO: PROBLEM IS that the add contact/remove contact, when they go from 0 -> !0 or !0 -> 0, the whole constraint is added/removed from the solver.
//The Added/Removed contact methods here will run ambiguously before or after they are removed from the solver.
//That ambiguous order doesn't really matter though, since everything that these add/remove methods do is local to this solver object and its children.
//It doesn't go out and modify any external values on referenced entities. That only happens when it's added or removed from the solver by whatever owns this object!
//To avoid ANY ambiguity, some third party is now responsible for adding and removing contacts from this.
///<summary>
/// Adds a contact to be managed by the constraint.
///</summary>
///<param name="contact">Contact to add.</param>
public override void AddContact(Contact contact)
{
contact.Validate();
ContactPenetrationConstraint penetrationConstraint = penetrationConstraintPool.Pop();
penetrationConstraint.Setup(this, contact);
penetrationConstraints.Add(penetrationConstraint);
ContactFrictionConstraint frictionConstraint = frictionConstraintPool.Pop();
frictionConstraint.Setup(this, penetrationConstraint);
frictionConstraints.Add(frictionConstraint);
}
///<summary>
/// Configures the friction constraint for a new contact.
///</summary>
///<param name="contactManifoldConstraint">Manifold to which the constraint belongs.</param>
///<param name="penetrationConstraint">Penetration constraint associated with this friction constraint.</param>
public void Setup(ContactManifoldConstraint contactManifoldConstraint,
ContactPenetrationConstraint penetrationConstraint)
{
ContactManifoldConstraint = contactManifoldConstraint;
PenetrationConstraint = penetrationConstraint;
IsActive = true;
linearAX = 0;
linearAY = 0;
linearAZ = 0;
entityA = contactManifoldConstraint.EntityA;
entityB = contactManifoldConstraint.EntityB;
}
///<summary>
/// Adds a contact to be managed by the constraint.
///</summary>
///<param name="contact">Contact to add.</param>
public override void AddContact(Contact contact)
{
contact.Validate();
ContactPenetrationConstraint 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);
}
}
///<summary>
/// Cleans up the constraint.
///</summary>
public override void CleanUp()
{
base.CleanUp();
//Deactivate any remaining constraints.
for (int i = penetrationConstraints.Count - 1; i >= 0; i--)
{
ContactPenetrationConstraint penetrationConstraint = penetrationConstraints.Elements[i];
penetrationConstraint.CleanUp();
penetrationConstraints.RemoveAt(i);
penetrationConstraintPool.Push(penetrationConstraint);
}
if (twistFriction.isActive)
{
twistFriction.CleanUp();
slidingFriction.CleanUp();
}
}
///<summary>
/// Cleans up the constraint.
///</summary>
public override void CleanUp()
{
base.CleanUp();
//Deactivate any remaining constraints.
for (int i = penetrationConstraints.Count - 1; i >= 0; i--)
{
ContactPenetrationConstraint penetrationConstraint = penetrationConstraints.Elements[i];
penetrationConstraint.CleanUp();
penetrationConstraints.RemoveAt(i);
penetrationConstraintPool.Push(penetrationConstraint);
}
for (int i = frictionConstraints.Count - 1; i >= 0; i--)
{
ContactFrictionConstraint frictionConstraint = frictionConstraints.Elements[i];
frictionConstraint.CleanUp();
frictionConstraints.RemoveAt(i);
frictionConstraintPool.Push(frictionConstraint);
}
}
///<summary>
/// Constructs a new nonconvex manifold constraint.
///</summary>
public NonConvexContactManifoldConstraint(CollidablePairHandler pairHandler)
: base(pairHandler)
{
//All of the constraints are always in the solver group. Some of them are just deactivated sometimes.
//This reduces some bookkeeping complications.
penetrationConstraints = new RawList <ContactPenetrationConstraint>(4);
frictionConstraints = new RawList <ContactFrictionConstraint>(4);
for (int i = 0; i < 4; i++)
{
ContactPenetrationConstraint penetrationConstraint = new ContactPenetrationConstraint();
penetrationConstraintPool.Push(penetrationConstraint);
Add(penetrationConstraint);
ContactFrictionConstraint frictionConstraint = new ContactFrictionConstraint();
frictionConstraintPool.Push(frictionConstraint);
Add(frictionConstraint);
}
}
///<summary>
/// Constructs a new convex contact manifold constraint.
///</summary>
public ConvexContactManifoldConstraint(CollidablePairHandler pairHandler)
: base(pairHandler)
{
//All of the constraints are always in the solver group. Some of them are just deactivated sometimes.
//This reduces some bookkeeping complications.
penetrationConstraints = new RawList <ContactPenetrationConstraint>(4);
//Order matters in this adding process. Sliding friction computes some information used by the twist friction, and both use penetration impulses.
for (int i = 0; i < 4; i++)
{
ContactPenetrationConstraint penetrationConstraint = new ContactPenetrationConstraint();
Add(penetrationConstraint);
penetrationConstraintPool.Push(penetrationConstraint);
}
slidingFriction = new SlidingFrictionTwoAxis();
Add(slidingFriction);
twistFriction = new TwistFrictionConstraint();
Add(twistFriction);
}
