Shader, adjusted.

 

Edited: The render, above, was without GC 2.2 set for the grey map.  Once that is done... the result is pretty much the same.

The matter quickly begins to look "non-trivial", as Spanki liked to say, from my perspective as one who lacks the BB-level math skillz.  :unsure:  :sad:

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Cage can be an opinionated jerk who posts without thinking.  He apologizes for this.  He's honestly not trying to be a turkeyhead.

Cage had some freebies, compatible with Poser 11 and below.  His Python scripts were saved at archive.org, along with the rest of the Morphography site, where they were hosted.