CrunkLord420 gjk/epa can be used for any shapes. It's just a neat algorithm that gives you: - collision check - shortest vector to resolve penetration You need that latter one to actually know how to resolve the collision. It's not enough to know if two objects overlap. You also need to know how to best resolve that overlapping. (okay for spheres only that is trivial. But spheres and boxes?) Gjk/epa does that.