imsize 1366 768
eye 0 5 -2
viewdir 0 -0.2 1
hfov 60
updir 0 1 0
bkgcolor 0.4 0.5 0.6
depthcueing 0.5 0.5 0.5 1 0.4 60 0
light 0 -1 0 0 1 1 1

mtlcolor 1 0.6 0.6 1 1 1 0.2 0.4 0.6 60 0.9 2
sphere -1.5 4 15 1

mtlcolor 0.6 0.6 1 1 1 1 0.2 0.4 0.6 60 0.9 2
sphere 0 -1 12 2

mtlcolor 0.6 1 0.6 1 1 1 0.2 0.4 0.6 60 1 2
sphere 6 8 20 3

mtlcolor 1 1 0.6 1 1 1 0.2 0.4 0.6 60 0.9 2
sphere -6 -8 20 4

mtlcolor 0.7 0.6 0.8 0.5 0.5 0.5 0.2 0.8 0.1 20 0.5 1.5
v 10 0 5
v -10 0 5
v -10 0 25
v 10 0 25

f 1 2 3
f 1 3 4