Dear waggy, Christian, and Stephen,

Thank you all for the input.

I'm still going through some of the quick codes you've written for me, and still
learning. However, some quick thoughts:

"waggy" <hon### [at] handbasketorg> wrote:

> Although this is true for an arbitrary mesh, when rendering a function...

Although I understand the advantages of functions vs. mesh data, I want to keep
the conversation focused on mesh definitions; it's the more general scenario,
and I want to see that POV-Ray can do in this respect.

I want to also raise the point that Christian made about the difficulty (he
didn't quite say 'difficult') with coloring the meshes.

My main concern with beginning to learn POV-Ray was due to Ankur Pawar, who has
a wonderful gallery on flicker:
http://www.flickr.com/photos/powerofankur/

You can also see that he has some beautiful surfaces rendered in Sunflow:
http://www.flickr.com/photos/powerofankur/5771193670/
http://www.flickr.com/photos/powerofankur/5210558726/
http://www.flickr.com/photos/powerofankur/4792169852/

From what I gather, these were all generated from mesh data and not function
descriptions. Notice also that the color of the meshes were generated in Matlab
for some of these (I will have to ask him how he did that!)

From my correspondence with Ankur, he mentioned that he preferred Sunflow, as he
found it much easier to generate these sorts of results, in contrast with
POV-Ray.

Of course, I'm left to wonder whether POV-Ray is -just as good- and can generate
the same sort of results with a modest degree of effort.

Comments? Hopefully, I will e-mail this thread to Ankur, and perhaps he will
join us in the discussion as well.

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> "waggy" <hon### [at] handbasketorg> wrote:
>
> > Although this is true for an arbitrary mesh, when rendering a function...
>
> Although I understand the advantages of functions vs. mesh data, I want to keep
> the conversation focused on mesh definitions; it's the more general scenario,
> and I want to see that POV-Ray can do in this respect.

Ah, but surface texture definitions apply regardless of the type of object.  The
texture I posted should look pretty much the same on a mesh.  (The only issues I
can think of being how well it hides or accentuates discretization artifacts,
and that it will be applied to one surface rather than two so a transparency
adjustment may be in order.)

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waggy wrote:

> Ah, but surface texture definitions apply regardless of the type of object.

not quite, as some textures may be difficult to define as 3d pattern,
but only some objects support uv-mapping.

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TSGM wrote:

> I want to also raise the point that Christian made about the difficulty (he
> didn't quite say 'difficult') with coloring the meshes.

Actually I just noticed that the mesh2 object supports specifying a
texture index for each face separately. So, the functionality is already
there and it shouldn't be too hard to extend the output of the surf2pov
function with color information.

In order to still retain control over other aspects of the texture
the exported texture list could call a FACE_TEXTURE(COLOR) macro that
needs to be defined by the scene prior to #including the data.

> From what I gather, these were all generated from mesh data and not function
> descriptions. Notice also that the color of the meshes were generated in Matlab
> for some of these (I will have to ask him how he did that!)

As far as I see only two of his images are tagged with povray and those
do not look like precolored meshes.

> Of course, I'm left to wonder whether POV-Ray is -just as good- and can generate
> the same sort of results with a modest degree of effort.

One of the problems may also be that your requirements are still a
bit vague. The Julia reference from your first post is quite a different
beast than a colored mesh plot.

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Hello everyone,

      I use that functionality of povray which can be generated form other
software or language and can be exported. Till now I have not used textures in
povray mesh.When MATLAB generates a mesh or surf it also assign colors to its
faces we can easily get those colors and export it.

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