Ray Tracing, Bounding Volume Hierarchy, Bvh, Axis Aligned, Tetrahedron Octahedron.
have a tetrahedron where each axis-aligned plane normal points towards the inside. Then, if our ray is originating on the side of a plane normal, this plane is a tmax candidate. Otherwise, it is a tmin candidate, because the ray has to intersect the backside of the plane at some point if it is to