Exemplo n.º 1
0
        public void AddPair(object proxyUserDataA, object proxyUserDataB)
        {
            b2FixtureProxy proxyA = (b2FixtureProxy)proxyUserDataA;
            b2FixtureProxy proxyB = (b2FixtureProxy)proxyUserDataB;

            b2Fixture fixtureA = proxyA.fixture;
            b2Fixture fixtureB = proxyB.fixture;

            int indexA = proxyA.childIndex;
            int indexB = proxyB.childIndex;

            b2Body bodyA = fixtureA.GetBody();
            b2Body bodyB = fixtureB.GetBody();

            // Are the fixtures on the same body?
            if (bodyA == bodyB)
            {
                return;
            }

            // TODO_ERIN use a hash table to remove a potential bottleneck when both
            // bodies have a lot of contacts.
            // Does a contact already exist?
            b2ContactEdge edge = bodyB.GetContactList();

            while (edge)
            {
                if (edge.other == bodyA)
                {
                    b2Fixture fA = edge.contact.GetFixtureA();
                    b2Fixture fB = edge.contact.GetFixtureB();
                    int       iA = edge.contact.GetChildIndexA();
                    int       iB = edge.contact.GetChildIndexB();

                    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 user filtering.
            if (m_contactFilter && m_contactFilter.ShouldCollide(fixtureA, fixtureB) == false)
            {
                return;
            }

            // Call the factory.
            b2Contact c = b2Contact.Create(fixtureA, indexA, fixtureB, indexB, m_allocator);

            if (c == null)
            {
                return;
            }

            // Contact creation may swap fixtures.
            fixtureA = c.GetFixtureA();
            fixtureB = c.GetFixtureB();
            indexA   = c.GetChildIndexA();
            indexB   = c.GetChildIndexB();
            bodyA    = fixtureA.GetBody();
            bodyB    = fixtureB.GetBody();

            // Insert into the world.
            c.m_prev = null;
            c.m_next = m_contactList;
            if (m_contactList != null)
            {
                m_contactList.m_prev = c;
            }
            m_contactList = c;

            // Connect to island graph.

            // Connect to body A
            c.m_nodeA.contact = c;
            c.m_nodeA.other   = bodyB;

            c.m_nodeA.prev = null;
            c.m_nodeA.next = bodyA.m_contactList;
            if (bodyA.m_contactList != null)
            {
                bodyA.m_contactList.prev = &c.m_nodeA;
            }
            bodyA.m_contactList = &c.m_nodeA;

            // Connect to body B
            c.m_nodeB.contact = c;
            c.m_nodeB.other   = bodyA;

            c.m_nodeB.prev = null;
            c.m_nodeB.next = bodyB.m_contactList;
            if (bodyB.m_contactList != null)
            {
                bodyB.m_contactList.prev = &c.m_nodeB;
            }
            bodyB.m_contactList = &c.m_nodeB;

            // Wake up the bodies
            bodyA.SetAwake(true);
            bodyB.SetAwake(true);

            ++m_contactCount;
        }
Exemplo n.º 2
0
        // This is a callback from the broadphase when two AABB proxies begin
        // to overlap. We create a b2Contact to manage the narrow phase.
        public void AddPair(object proxyUserDataA, object proxyUserDataB)
        {
            b2Fixture fixtureA = proxyUserDataA as b2Fixture;
            b2Fixture fixtureB = proxyUserDataB as b2Fixture;

            b2Body bodyA = fixtureA.GetBody();
            b2Body bodyB = fixtureB.GetBody();

            // Are the fixtures on the same body?
            if (bodyA == bodyB)
            {
                return;
            }

            // Does a contact already exist?
            b2ContactEdge edge = bodyB.GetContactList();

            while (edge != null)
            {
                if (edge.other == bodyA)
                {
                    b2Fixture fA = edge.contact.GetFixtureA();
                    b2Fixture fB = edge.contact.GetFixtureB();
                    if (fA == fixtureA && fB == fixtureB)
                    {
                        return;
                    }
                    if (fA == fixtureB && fB == fixtureA)
                    {
                        return;
                    }
                }
                edge = edge.next;
            }

            //Does a joint override collision? Is at least one body dynamic?
            if (bodyB.ShouldCollide(bodyA) == false)
            {
                return;
            }

            // Check user filtering
            if (m_contactFilter.ShouldCollide(fixtureA, fixtureB) == false)
            {
                return;
            }

            // Call the factory.
            b2Contact c = m_contactFactory.Create(fixtureA, fixtureB);

            // Contact creation may swap shapes.
            fixtureA = c.GetFixtureA();
            fixtureB = c.GetFixtureB();
            bodyA    = fixtureA.m_body;
            bodyB    = fixtureB.m_body;

            // Insert into the world.
            c.m_prev = null;
            c.m_next = m_world.m_contactList;
            if (m_world.m_contactList != null)
            {
                m_world.m_contactList.m_prev = c;
            }
            m_world.m_contactList = c;


            // Connect to island graph.

            // Connect to body A
            c.m_nodeA.contact = c;
            c.m_nodeA.other   = bodyB;

            c.m_nodeA.prev = null;
            c.m_nodeA.next = bodyA.m_contactList;
            if (bodyA.m_contactList != null)
            {
                bodyA.m_contactList.prev = c.m_nodeA;
            }
            bodyA.m_contactList = c.m_nodeA;

            // Connect to body 2
            c.m_nodeB.contact = c;
            c.m_nodeB.other   = bodyA;

            c.m_nodeB.prev = null;
            c.m_nodeB.next = bodyB.m_contactList;
            if (bodyB.m_contactList != null)
            {
                bodyB.m_contactList.prev = c.m_nodeB;
            }
            bodyB.m_contactList = c.m_nodeB;

            ++m_world.m_contactCount;
            return;
        }