o Plane v -0.5 -0.5 0.0 v 0.5 -0.5 0.0 v -0.5 0.5 0.0 v 0.5 0.5 0.0 vt 0 0 vt 1 0 vt 1 1 vt 0 1 vn 0 0 1 s off f 1/1/1 2/2/1 4/3/1 3/4/1