POV-Ray : Newsgroups : povray.pov4.discussion.general : 3D warp repeat for primitives : Re: 3D warp repeat for primitives Server Time13 Sep 2024 13:46:49 EDT (-0400)
 Re: 3D warp repeat for primitives
 From: Bald Eagle Date: 9 Aug 2024 14:30:00 Message:
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"Kenneth" <kdw### [at] gmailcom> wrote:

> As in, taking any pre-made object and turning it into a triangle mesh surface--
> even objects with holes, voids, undercuts, etc. So far, I have solved only 'step
> A'-- finding regularly-spaced points on all the surfaces, without picking
> redundant points. Even that's not quite perfect, though.

Using something like a progressive trace () to generate a crossing number (used
for insidedness tests for polygons, but storing all of the crossing points would
allow this.

https://news.povray.org/povray.pov4.discussion.general/message/%3Cweb.662158a818d5960295196c9d25979125%40news.povray.or
g%3E/#%3Cweb.662158a818d5960295196c9d25979125%40news.povray.org%3E

> The *bigger* problem is
> how to logically connect those points to make triangles... which is the 'holy
> grail' of the entire scheme, of course!

Well, that's why it's easy to convert parametric shapes into meshes, since you
can cycle through the values and calculate where the next point is.

Looking at primitive CSG's or isosurfaces, you're sort of working backwards.
You have a value of sorts, but you don't have access to the underlying mechanism
of how it was generated. (This is also what bothers me about POV-Ray's
parametric {} object - why the hell is it so slow? )

Anyway, none of that really has to do with the repeat warp mechanism for
primitives. . .

- BW
```