// These support body activation/deactivation.
internal void CreateProxies(IBroadPhase broadPhase, ref Transform xf)
{
Debug.Assert(ProxyCount == 0);
// Create proxies in the broad-phase.
ProxyCount = Shape.ChildCount;
for (int i = 0; i < ProxyCount; ++i)
{
FixtureProxy proxy = new FixtureProxy();
Shape.ComputeAABB(out proxy.AABB, ref xf, i);
proxy.Fixture = this;
proxy.ChildIndex = i;
//FPE note: This line needs to be after the previous two because FixtureProxy is a struct
proxy.ProxyId = broadPhase.AddProxy(ref proxy);
Proxies[i] = proxy;
}
}
internal void Synchronize(IBroadPhase broadPhase, ref Transform transform1, ref Transform transform2)
{
if (ProxyCount == 0)
{
return;
}
for (int i = 0; i < ProxyCount; ++i)
{
FixtureProxy proxy = Proxies[i];
// Compute an AABB that covers the swept Shape (may miss some rotation effect).
AABB aabb1, aabb2;
Shape.ComputeAABB(out aabb1, ref transform1, proxy.ChildIndex);
Shape.ComputeAABB(out aabb2, ref transform2, proxy.ChildIndex);
proxy.AABB.Combine(ref aabb1, ref aabb2);
Vector2 displacement = transform2.p - transform1.p;
broadPhase.MoveProxy(proxy.ProxyId, ref proxy.AABB, displacement);
}
}
// 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;
}
}