POV-Ray : Newsgroups : povray.advanced-users : smooth_triangle normals : smooth_triangle normals Server Time
27 Mar 2023 05:33:47 EDT (-0400)
  smooth_triangle normals  
From: Bald Eagle
Date: 26 Sep 2020 09:10:07
Message: <web.5f6f3d5eca9fa6351f9dae300@news.povray.org>
I've been rendering quite a few illustrations for


and have been mixing the very broad strokes with digging into the very detailed

At the moment, having some issues with smooth_triangles and want to verify a few
things, so I want to make sure everything is absolutely correct. Assume I'm
laying out a grid of squares made up of 2 triangles each.

All my flat triangles are fine, and I can see all of the individual triangles,
since all of the face normals are sufficiently different.

With smooth_triangles, even though the vertex coordinates are the same,
sometimes I get the degenerate triangle warning when working out the vertex
normal vectors.

When I use the corners of the square to calculate the normals, the edge between
the two triangles of the square softens/goes away, but the edges between all of
the squares are still pretty abrupt.
When I try to use a small dy or dx offset to calculate the normals, I get a lot
of the degenerate triangle warnings and few if any visible triangles.  Not sure


When calculating the normals, do I use the remaining two triangle vertices, or
the orthogonal edge vectors of the square?
Do I normalize the vectors before using vcross()?
Do I normalize the resulting vertex normal vectors?


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