o
mtllib floor.mtl
v -1 -1 -1
v  1 -1 -1
v  1 -1  1
v -1 -1  1

vt 0 0
vt .25 0
vt .25 .25
vt 0 .25

vn 0 1 0
usemtl floor

f 3/3/1 2/2/1 1/1/1
f 4/4/1 3/3/1 1/1/1