clipka <ano### [at] anonymousorg> wrote:
> One thing is for sure: You've seriously screwed up on the icosahedron.
>
> Apparently you misinterpreted the positions of the individual points,
> probably thinking that Phi<1, but in fact Phi>1.
>
> Swapping the 1's and Phi's in the TwentyHedron definition gives a nice
> regular icosahedron.

Are you just pulling my leg now?
Because my definition of Phi is in the code, and when I comment out ALL of the
vnormalize() directives, I get ... an icosahedron.

And considering that the vertices are defined by ALL of the permutations of
+/-1, 0, and +/-Phi, I don't see how "swapping" those values in any given vertex
doesn't just give me ... another one of the points I already have.

When I added the y-rotated 90 and 180 instances, the lighting made it _look_
strange, like one triangle was rotated and skewed at a weird angle, but I added
a granite surface normal and moved the light source, and it's --- just an
icosahedron.   Were you seeing the same optical illusion I did?

> You also got the front top cap's ordering of points wrong. Fixing that
> will give you a nicely textured mesh.

Correct.   I've fixed that, and thank you.


I'm going to add a little bit to my code to visualize the vertex normals of the
smooth_triangles, because I'm having a devil of a time visualizing your
description of how that all works at the moment.  Your explanation of the
situation is perfectly clear - the 3D result of that is just [for me] less so.

Please also notice that there are a few green pixels in/on the lower left MESH
icosahdron - the rotate y*180 degree instance.  A small, but seemingly important
detail, if using mesh{} is supposed to eliminate that problem.
I haven't declared an inside_vector  -  could it be related in some way to that?

Also, if only _some_ of the vertices are normalized to the unit sphere radius,
some very nice stellated / fractal shapes are produced.

These would make a very nice basis for anyone who wanted crystals, 3D
snowflakes, etc.

Further deviations from the unit radius upon each facial subdivision would
likely produce some more interesting results.

All of these experiments - just give rise to more experiments  :)

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