Documentation
# cornell_box.obj and cornell_box.mtl are grabbed from Intel's embree project.
# original cornell box data
  # comment

# empty line including some space
   

mtllib cornell_box.mtl

o floor
usemtl white
v 552.8 0.0   0.0
v 0.0   0.0   0.0
v 0.0   0.0 559.2
v 549.6 0.0 559.2

v 130.0 0.0  65.0
v  82.0 0.0 225.0
v 240.0 0.0 272.0
v 290.0 0.0 114.0

v 423.0 0.0 247.0
v 265.0 0.0 296.0
v 314.0 0.0 456.0
v 472.0 0.0 406.0

f 1 2 3 4 
f 8 7 6 5
f 12 11 10 9

o light
usemtl light
v 343.0 548.0 227.0
v 343.0 548.0 332.0
v 213.0 548.0 332.0
v 213.0 548.0 227.0
f -4 -3 -2 -1

o ceiling
usemtl white
v 556.0 548.8 0.0
v 556.0 548.8 559.2
v 0.0 548.8 559.2
v 0.0 548.8 0.0
f -4 -3 -2 -1

o back_wall
usemtl white
v 549.6   0.0 559.2
v 0.0   0.0 559.2
v 0.0 548.8 559.2
v 556.0 548.8 559.2
f -4 -3 -2 -1

o front_wall
usemtl blue
v 549.6   0.0 0
v 0.0   0.0 0
v 0.0 548.8 0
v 556.0 548.8 0
#f -1 -2 -3 -4

o green_wall
usemtl green
v    0.0   0.0 559.2
v    0.0   0.0   0.0
v    0.0 548.8   0.0
v    0.0 548.8 559.2
f -4 -3 -2 -1

o red_wall
usemtl red
v    552.8   0.0   0.0
v    549.6   0.0 559.2
v    556.0 548.8 559.2
v    556.0 548.8   0.0
f -4 -3 -2 -1

o short_block
usemtl white

v    130.0 165.0  65.0
v     82.0 165.0 225.0
v    240.0 165.0 272.0
v    290.0 165.0 114.0
f -4 -3 -2 -1

v    290.0   0.0 114.0
v    290.0 165.0 114.0
v    240.0 165.0 272.0
v    240.0   0.0 272.0
f -4 -3 -2 -1

v    130.0   0.0  65.0
v    130.0 165.0  65.0
v    290.0 165.0 114.0
v    290.0   0.0 114.0
f -4 -3 -2 -1

v     82.0   0.0 225.0
v     82.0 165.0 225.0
v    130.0 165.0  65.0
v    130.0   0.0  65.0
f -4 -3 -2 -1

v    240.0   0.0 272.0
v    240.0 165.0 272.0
v     82.0 165.0 225.0
v     82.0   0.0 225.0
f -4 -3 -2 -1

o tall_block
usemtl white

v    423.0 330.0 247.0
v    265.0 330.0 296.0
v    314.0 330.0 456.0
v    472.0 330.0 406.0
f -4 -3 -2 -1

usemtl white
v    423.0   0.0 247.0
v    423.0 330.0 247.0
v    472.0 330.0 406.0
v    472.0   0.0 406.0
f -4 -3 -2 -1

v    472.0   0.0 406.0
v    472.0 330.0 406.0
v    314.0 330.0 456.0
v    314.0   0.0 456.0
f -4 -3 -2 -1

v    314.0   0.0 456.0
v    314.0 330.0 456.0
v    265.0 330.0 296.0
v    265.0   0.0 296.0
f -4 -3 -2 -1

v    265.0   0.0 296.0
v    265.0 330.0 296.0
v    423.0 330.0 247.0
v    423.0   0.0 247.0
f -4 -3 -2 -1