How are you determining the set of candidate tripolys for the ray-casting?  Is it just the vpolys for the closest vertex?

If so, might it help to get neighbor polys, as well, to extend the outer ring, as it were?  Maybe as an optional setting.

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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.