Box2DX.Dynamics.ContactFilter.ShouldCollide C# (CSharp) Метод

        public virtual bool ShouldCollide(Shape shape1, Shape shape2)
        {
            FilterData filter1 = shape1.FilterData;
            FilterData filter2 = shape2.FilterData;

            if (filter1.GroupIndex == filter2.GroupIndex && filter1.GroupIndex != 0)
            {
                return filter1.GroupIndex > 0;
            }

            bool collide = (filter1.MaskBits & filter2.CategoryBits) != 0 && (filter1.CategoryBits & filter2.MaskBits) != 0;
            return collide;
        }

        // This is the top level collision call for the time step. Here
        // all the narrow phase collision is processed for the world
        // contact list.
        public void Collide()
        {
            // Update awake contacts.
            Contact c = _contactList;

            while (c != null)
            {
                Fixture fixtureA = c.GetFixtureA();
                Fixture fixtureB = c.GetFixtureB();
                Body    bodyA    = fixtureA.GetBody();
                Body    bodyB    = fixtureB.GetBody();

                if (bodyA.IsSleeping() && bodyB.IsSleeping())
                {
                    c = c.GetNext();
                    continue;
                }

                // Is this contact flagged for filtering?
                if ((c.Flags & ContactFlag.FilterFlag) == ContactFlag.FilterFlag)
                {
                    //TODO: The following code (next 4 if blocks) use a class and thus copy by ref. It might expect to copy by value
                    // Are both bodies static?
                    if (bodyA.IsStatic() && bodyB.IsStatic())
                    {
                        Contact cNuke = c;
                        c = cNuke.GetNext();
                        Destroy(cNuke);
                        continue;
                    }

                    // Does a joint override collision?
                    if (bodyB.IsConnected(bodyA))
                    {
                        Contact cNuke = c;
                        c = cNuke.GetNext();
                        Destroy(cNuke);
                        continue;
                    }

                    // Check user filtering.
                    if (_contactFilter.ShouldCollide(fixtureA, fixtureB) == false)
                    {
                        Contact cNuke = c;
                        c = cNuke.GetNext();
                        Destroy(cNuke);
                        continue;
                    }

                    // Clear the filtering flag.
                    c.Flags &= ~ContactFlag.FilterFlag;
                }

                int  proxyIdA = fixtureA.ProxyId;
                int  proxyIdB = fixtureB.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;
                    c = cNuke.GetNext();
                    Destroy(cNuke);
                    continue;
                }

                // The contact persists.
                c.Update(_contactListener);
                c = c.GetNext();
            }
        }