g grass
v -50 0 50
v -50 0 -50
v 50 0 -50
v 50 0 50
vt 0.874536693 0.996856332
vt 0.680811822 0.996856272
vt 0.680811822 0.803808928
vt 0.874536693 0.803808928
vn -0 1 0
vn -0 1 0
vn -0 1 0
vn -0 1 0
g grass_0
f 3/3/3 2/2/2 1/1/1
f 4/4/4 3/3/3 1/1/1