Ray Tracing, Bounding Volume Hierarchy, Bvh, Axis Aligned, Tetrahedron Octahedron.
might end up with a faster overall hierarchy. Unfortunately for us, a quick google search shows us that there is not much on the table here. The best general ray-tetrahedra test I could find is the one from Christer Ericson. However, since the axis-aligned restriction may give us new possibilities,