// Broad-phase callback. private void AddPair(ref FixtureProxy proxyA, ref FixtureProxy proxyB) { FSFixture fixtureA = proxyA.Fixture; FSFixture fixtureB = proxyB.Fixture; int indexA = proxyA.ChildIndex; int indexB = proxyB.ChildIndex; FSBody bodyA = fixtureA.Body; FSBody 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) { FSFixture fA = edge.Contact.FixtureA; FSFixture 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; } 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); // 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; }
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 FSFixture fixtureA = c.FixtureA; FSFixture fixtureB = c.FixtureB; int indexA = c.ChildIndexA; int indexB = c.ChildIndexB; FSBody bodyA = fixtureA.Body; FSBody bodyB = fixtureB.Body; if (bodyA.Awake == false && bodyB.Awake == false) { #if USE_ACTIVE_CONTACT_SET ActiveContacts.Remove(c); #endif continue; } // Is this contact flagged for filtering? if ((c.Flags & ContactFlags.Filter) == ContactFlags.Filter) { // 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.Flags &= ~ContactFlags.Filter; } 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 }