It's been mentioned before that the disc object in POV-Ray
is considered an infinitely thin object with scalable dimensions
allowed only in two directions. People have reported problems
using this primitive with other objects and maintaining uniform
textures and pigments when the two are combined. I too have
witnessed the peculiarity in the past.

    Which leads to my question. With regards to sors, prisms,
and lathes, are they too considered to be infinitely thin objects,
with the only difference they have from a disc object would be
that the have been folded in 3d space to form a definable shape.
The reason I ask is that I have been having problems with getting
texture and pigments to match when I do c.s.g. operations
combining standard primitives and the above mentioned objects.
Also if there is an infinitely thin wall this can lead to other problems
in scaling when you try to net identical shapes within each other.
If you undersize in transparent textures the lights reflection
between the walls will give inaccurate refraction. Over sizing to
avoid coincident surfaces creates another problem in that
if the two surfaces are infinitely thin you can not scale up
without actually reproducing the exact same object as the first.

  Has anybody else experience this pigmentation problem, or if
you are in the know can you enlighten me on a the thickness question.?

Thanks

K.Tyler

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In article <35CF2FDB.26B4BE1D@pacbell.net>, tyl### [at] pacbellnet says...
>
 With regards to sors, prisms,
>and lathes, are they too considered to be infinitely thin objects,
>with the only difference they have from a disc object would be
>that the have been folded in 3d space to form a definable shape.

Lathes, SOR, and prisms are "plain" shapes, with a well-defined 
inside/outside, and should work (and usually does) well in CSG.
However, high order calculations they require sometimes leads
to unexpected results.
Have you tried the STURM keyword with these ?

Cheers,
Fabien.

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