v -0.500000 -0.500000 0.000000
v 0.500000 -0.500000 0.000000
v -0.500000 0.500000 0.000000
v 0.500000 0.500000 0.000000
vn 0.000000 0.000000 1.000000
vt 0 0
vt 1 0
vt 0 1
vt 1 1
f 2/2/1 4/4/1 3/3/1
f 1/1/1 2/2/1 3/3/1