v 0 0 0
v 0 0 1
v 0 1 0
v 0 1 1
v 1 0 0
v 1 0 1
v 1 1 0
v 1 1 1
vt 0 0
vt 0 0
vt 0 0
vt 0 0
vt 0 0
vt 0 0
vt 0 0
vt 0 0
f 3/1 4/2 8/3 
f 3/1 1/4 2/5 
f 4/2 2/5 6/6 
f 8/3 6/6 5/7 
f 2/5 1/4 5/7 
f 1/4 3/1 7/8 
f 8/3 7/8 3/1 
f 2/5 4/2 3/1 
f 6/6 8/3 4/2 
f 5/7 7/8 8/3 
f 5/7 6/6 2/5 
f 7/8 5/7 1/4