v 1.0 1.0 1.0
v 1.0 1.0 -1.0
v -1.0 1.0 -1.0
v -1.0 1.0 1.0
v 0.0 3.0 0.0
g mountain
f 1 2 5
f 2 3 5
f 3 4 5
f 4 1 5