Model a Fresnel lens in BRL-CAD.

Your model should define one or more regions and be free of modeling errors such as overlaps.  Submit your .g file and a 1024x1024 rendering.

References:

• http://brlcad.org/wiki/Documentation (see the MGED tutorial and cheat sheets)
• rt -s1024 -A0.75 -c {set ambSamples=128}  (will make a nice rendering)
• rtcheck  (checks for overlaps)