Here are various goodies (read shaders) for RenderMan.

Note that the displacement-shaders work only on RenderMan 
implementations that support displacement mapping.
BMRT does not!
There might be problems using these shaders on the Quick RenderMan
implementation in NextStep. You can try to rename parameters if the 
shaders do not work for you.

Shader parameters:

Some shaders need to know the number of whorls (omax - omin, in terms of 
ShellyLib parameters) and the size in S-direction (smax - smin) 
of the shell they are applied to, in order to work properly.

For information on the other shader parameters, refer to the
sources of the shaders.

The shaders:

There are two groups, advanced shaders used in the new examples
in "pic/", and shaders that introduce more general surface properties
like ridges or ribs. Even though the general shaders are very
simple they are here, for the sake of completeness.

Advanced shaders:

precious.sl - shader source for the displacement of the "Precious Wentletrap"

drupe.sl - shader source for the displacement of the "Pink Pacific Drupe"

drupecol.sl - shader source for the color of the "Pink Pacific Drupe"

General shaders:

ribs_sin_u.sl - shader source for sinusoidal ribs in O-direction

ribs_sin_v.sl - shader source for sinusoidal ribs in S-direction

waves_sin_u.sl - shader source for sinusoidal waves in O-direction

waves_sin_v.sl - shader source for sinusoidal waves in S-direction

