Eli Ewok Brody wrote:
> 
>  All --
>     I'm sure this has been a problem before, perhaps even solved before. At
> any rate, I am becoming desperate. sPatch objects (eg. Unions of bicubic
> patches) do not support world xyz coords. This turns shading into a
> nightmare. I've tried lots of combinations - not making it a union, merging
> them, assigning textures individually... nothing works. It's possible to
> make a triangle mesh out of it, but I have never been impressed by meshes,
> and would rather use slightly more resolution independant objects. (The best
> being Our Friend the Primitive.)
>     What can I do? Is there some bug in POV-Ray? Is there something simple
> I'm overlooking?

This is certainly a bit the wrong group for such things (so i set followup
to p.a-u)

First of all bicubic patches are internally converted to meshes in povray
so it's not reasonable why you couldn't achieve the same accuracy with a
mesh.  Another thing which i already mentioned in another reply, bicubic
patches are a very limited shape, only certain surfaces can be modelled
and when you try to approximate cylinders, spheres etc. with several
patches you will have to expect strange results.

Christoph

-- 
Christoph Hormann <chr### [at] gmxde>
IsoWood include, radiosity tutorial, TransSkin and other 
things on: http://www.schunter.etc.tu-bs.de/~chris/

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You wrote:
    <<First of all bicubic patches are internally converted to meshes in
povray so it's not reasonable why you couldn't achieve the same accuracy
with a mesh.  Another thing which i already mentioned in another reply,
bicubic patches are a very limited shape, only certain surfaces can be
modelled and when you try to approximate cylinders, spheres etc. with
several patches you will have to expect strange results.>>

    Interesting. That's a smart idea - POV probably converts most objects
(excepting primitives) to meshes. I'll have to take a look at the source
code (and hope I can understand some of it).
    I'm really not looking for cylinders and the like. I have an object I
happen to like very much. It looks good, even with bicubic patches. It also
takes up a relatively small space (60K as opposed to five megs of
triangles). It just does strange things with the surface normal.

    The answers will come to me yet....
    Thanks again,
    -Eli

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In article <3b45c3f8@news.povray.org>,
 "Eli Ewok Brody" <ewo### [at] yahoocom> wrote:

>     Interesting. That's a smart idea - POV probably converts most objects
> (excepting primitives) to meshes.

Only bezier patches and height fields...most objects are rendered 
directly, and many just can't be reduced to a mesh.

-- 
Christopher James Huff - chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

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