RenderMan & RISpec, Volume shader for non-radial planet atmosphere

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RenderMan & RISpec >> Volume shader for non-radial planet atmosphere

by AltHero » Mon, 28 Mar 2011 04:06:30 GMT

Hallo to all,
volume shaders to simulate a planet atmosphere are well known starting
from "Texturing & Modeling 3rd ed." planetatmo.sl shader (from
Gritz-Musgrave) that works pretty well, for spherical bodies. But gas
giant planets like Jupiter, Saturn etc. aren't spherical but
ellipsoidal. Does someone know how to handle that geometry and how to
modify the radial GADD proposed in TM 3? I tried to insert in rib file a
Z scaling attribute but - obiously - doesn't work. Moreover
planetatmo.sl seems affected by severe aliasing problems in planet limb
( the bright line that blends sky with ground is very thin) and I dont
know how to handle it.

Thanks for your help,

Giuseppe
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