I finally got my GJK algorithm working and now i want to be able to find the depth of the intersection of the two polyhedra in a particular direction (the direction of momentum). I figure the best way would be to find the distance from the origin of the minkowski difference to the hull of the minkowski difference. Is this the most efficient means? If so, im having several problems which include: A) efficiently calculating only the vertices located on the hull of the minkowski difference B) determining which triangular face of the polyhedral hull the ray from the origin will intersect with I've been told using an MPR algorithm would help me find the correct triangular face to intersect, but i can't find any in depth explanations of that algorithm, especially in 3D. Any help is greatly appretiated!