ref: 727cb178cfbc31d46098bcbb46ebf2452527025a dir: /mdl/basispt.obj/
mtllib basis.mtl v 0 0 0 v 1 0 0 v 0 1 0 v 0 0 1 p 1 usemtl x p 2 usemtl y p 3 usemtl z p 4