imsize 640 480
eye -2.5 2 -5
viewdir -0.2 0 -1
hfov 90
updir 0 1 0
bkgcolor 0.4 0.4 0.4

depthcueing 0.4 0.4 0.4 1 0.1 60 0
light 0 5 -7.5 1 1 1 1

mtlcolor 1 0.8 0.7 1 1 1 0.6 0.6 0 10
sphere -5 2 -10 2
sphere -3 2 -20 2
sphere 1.5 2 -30 2
sphere 13 2 -60 2