POV-Ray : Newsgroups : povray.general : uv mapping triangles in mesh {} : Re: uv mapping triangles in mesh {} Server Time
7 Dec 2023 09:18:16 EST (-0500)
  Re: uv mapping triangles in mesh {}  
From: Bald Eagle
Date: 5 Apr 2023 20:10:00
Message: <web.642e0d07eebe912c1f9dae3025979125@news.povray.org>
Thomas de Groot <tho### [at] degrootorg> wrote:
> Excellent progress, sir!

Thanks.  It's amazing what obsessing over the same ridiculous triangle diagram
for two weeks can accomplish.

{Mutters incoherently while fumbling with foil-wrapped vial of specially
prepared dried frog pills. =For Emergency Use Only=}

After I had gotten all of that sorted out to somewhat less than my satisfaction
(I still don't fully understand half of what I did with the logic and
"correction factors") I copied the working scene to another file, pasted in the
code to make a proper rectangle, daisy-chained together a bunch of arrays and
pattern-density calculating code, and rewrote Quicksort to handle my Nx3 data
array for the patterns.

(This looks fun.  I can learn a lot about triangles.   1618 lines of code

That confirmed what I had suspected - the actual area of a triangle covered in
black does not correspond to the perceived visual density of the pattern.  I
tried doing a few searches to see if there was some metric to measure this, and
if there was anything in the visual / psychological literature to account for
this and if it had a "name", and maybe some example diagrams and graphs, code,
or algorithms.

Looks like I'll have to do manual assignments or play with weighting the
contribution of lines based on their individual area and/or distance from the

Because this is a BLACK cat with some white patches sitting on a cream colored

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