g top
v 0.500000 0.500000 0.500000
v -0.500000 0.500000 0.500000
v -0.500000 -0.500000 -0.500000
v 0.500000 -0.500000 -0.500000
vt 1.0000 1.0000
vt 0.0000 1.0000
vt 0.0000 0.0000
vt 1.0000 0.0000
vn 0.0000 0.7071 -0.7071
s off
f 2/1/1 1/2/1 4/3/1 3/4/1