// Broad-phase callback.
private void AddPair(ref FixtureProxy proxyA, ref FixtureProxy proxyB)
{
Fixture fixtureA = proxyA.Fixture;
Fixture fixtureB = proxyB.Fixture;
int indexA = proxyA.ChildIndex;
int indexB = proxyB.ChildIndex;
Body bodyA = fixtureA.Body;
Body bodyB = fixtureB.Body;
// Are the fixtures on the same body?
if (bodyA == bodyB)
{
return;
}
// Does a contact already exist?
ContactEdge edge = bodyB.ContactList;
while (edge != null)
{
if (edge.Other == bodyA)
{
Fixture fA = edge.Contact.FixtureA;
Fixture fB = edge.Contact.FixtureB;
int iA = edge.Contact.ChildIndexA;
int iB = edge.Contact.ChildIndexB;
if (fA == fixtureA && fB == fixtureB && iA == indexA && iB == indexB)
{
// A contact already exists.
return;
}
if (fA == fixtureB && fB == fixtureA && iA == indexB && iB == indexA)
{
// A contact already exists.
return;
}
}
edge = edge.Next;
}
// Does a joint override collision? Is at least one body dynamic?
if (bodyB.ShouldCollide(bodyA) == false)
{
return;
}
//Check default filter
if (ShouldCollide(fixtureA, fixtureB) == false)
{
return;
}
// Check user filtering.
if (ContactFilter != null && ContactFilter(fixtureA, fixtureB) == false)
{
return;
}
//FPE feature: BeforeCollision delegate
if (fixtureA.BeforeCollision != null && fixtureA.BeforeCollision(fixtureA, fixtureB) == false)
{
return;
}
if (fixtureB.BeforeCollision != null && fixtureB.BeforeCollision(fixtureB, fixtureA) == false)
{
return;
}
// Call the factory.
Contact c = Contact.Create(fixtureA, indexA, fixtureB, indexB);
if (c == null)
{
return;
}
// Contact creation may swap fixtures.
fixtureA = c.FixtureA;
fixtureB = c.FixtureB;
bodyA = fixtureA.Body;
bodyB = fixtureB.Body;
// Insert into the world.
ContactList.Add(c);
#if USE_ACTIVE_CONTACT_SET
ActiveContacts.Add(c);
#endif
// Connect to island graph.
// Connect to body A
c._nodeA.Contact = c;
c._nodeA.Other = bodyB;
c._nodeA.Prev = null;
c._nodeA.Next = bodyA.ContactList;
if (bodyA.ContactList != null)
{
bodyA.ContactList.Prev = c._nodeA;
}
bodyA.ContactList = c._nodeA;
// Connect to body B
c._nodeB.Contact = c;
c._nodeB.Other = bodyA;
c._nodeB.Prev = null;
c._nodeB.Next = bodyB.ContactList;
if (bodyB.ContactList != null)
{
bodyB.ContactList.Prev = c._nodeB;
}
bodyB.ContactList = c._nodeB;
// Wake up the bodies
if (fixtureA.IsSensor == false && fixtureB.IsSensor == false)
{
bodyA.Awake = true;
bodyB.Awake = true;
}
}
internal void Collide()
{
// Update awake contacts.
#if USE_ACTIVE_CONTACT_SET
ActiveList.AddRange(ActiveContacts);
foreach (var c in ActiveList)
{
#else
for (int i = 0; i < ContactList.Count; i++)
{
Contact c = ContactList[i];
#endif
Fixture fixtureA = c.FixtureA;
Fixture fixtureB = c.FixtureB;
int indexA = c.ChildIndexA;
int indexB = c.ChildIndexB;
Body bodyA = fixtureA.Body;
Body bodyB = fixtureB.Body;
//Do no try to collide disabled bodies
if (!bodyA.Enabled || !bodyB.Enabled)
{
continue;
}
// Is this contact flagged for filtering?
if (c.FilterFlag)
{
// Should these bodies collide?
if (bodyB.ShouldCollide(bodyA) == false)
{
Contact cNuke = c;
Destroy(cNuke);
continue;
}
// Check default filtering
if (ShouldCollide(fixtureA, fixtureB) == false)
{
Contact cNuke = c;
Destroy(cNuke);
continue;
}
// Check user filtering.
if (ContactFilter != null && ContactFilter(fixtureA, fixtureB) == false)
{
Contact cNuke = c;
Destroy(cNuke);
continue;
}
// Clear the filtering flag.
c.FilterFlag = false;
}
bool activeA = bodyA.Awake && bodyA.BodyType != BodyType.Static;
bool activeB = bodyB.Awake && bodyB.BodyType != BodyType.Static;
// At least one body must be awake and it must be dynamic or kinematic.
if (activeA == false && activeB == false)
{
#if USE_ACTIVE_CONTACT_SET
ActiveContacts.Remove(c);
#endif
continue;
}
int proxyIdA = fixtureA.Proxies[indexA].ProxyId;
int proxyIdB = fixtureB.Proxies[indexB].ProxyId;
bool overlap = BroadPhase.TestOverlap(proxyIdA, proxyIdB);
// Here we destroy contacts that cease to overlap in the broad-phase.
if (overlap == false)
{
Contact cNuke = c;
Destroy(cNuke);
continue;
}
// The contact persists.
c.Update(this);
}
#if USE_ACTIVE_CONTACT_SET
ActiveList.Clear();
#endif
}
