Adding specific code for Tet + Bbox_3 do_intersect as it should be ok for Bbox_3 to degenerate. The previous code failed in case Bbox_3 is degenerate. I use the result = result || predicate(); to keep the maybe inside result. If certain the code returns early. I also avoid the %4 as this is a slow operation, but not sure that this is worth compared to the rest.