Ken <tyl### [at] pacbellnet> writes:
> 
>   First I am really talking about adding two major processes here. The
> first is the ability to internaly tessellate Pov primitives. The second
> would be the addition of subdivision surfaces. 

I agree (at least) on the second. We should also add NURBS support.
Both would make it easier for modellers to export to POV-Ray.

>   The point is that primitives are too perfect in some cases. Ever try
> to make a realistic looking rock from a sphere primitive by applying a
> normal to it ?
> 
>  I also think (and may be wrong) that with subdivision surfaces you can
> create smooth curves between intersecting objects that would normally in
> POV-Ray result only in perfect right angles.

I had completely understood your motivation (and I share it). Displacements
and smoothing are important tasks for the generation of high quality
images.

However, I think we should try another approach in POV-Ray than triangulate
the objects. I really like the fact that POV-Ray has a variety of objects
like spheres, boxes, cylinders, planes, etc. That's why I don't like
the idea of converting them into triangles, even if it only the case for
some objects. Particularly, I don't like this idea, because we have an
alternative which fits better in the philosophy of POV-Ray IMO:
isosurfaces. For me, they are something like an extension of blobs and 
polynomial objects.

Why should we choose to use isosurfaces when the rest of the world likes
triangles? First, we already have them in the megapatch and will have 
them in POV-Ray 3.5 (as far as I know). Second, at least displacement maps
are possible with them. You didn't comment on my picture
(http://www.fmi.uni-konstanz.de/~willhalm/bilder/displace.jpg), but I
think that it is not too far away from the image at
http://graphics.stanford.EDU/papers/displace/
(I even consider my picture as a proof of concept.)
I'm almost sure, that smooth conjunctions are possible as well. The
recent images in p.b.i with blobs suggest this.

So, what we need is a mechanism to automagically convert CSG objects
to isosurfaces inside POV-Ray.

Thomas

-- 
http://thomas.willhalm.de/ (includes pgp key)

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