Christoph Hormann <chr### [at] gmxde> wrote:
> Interesting tool but i wonder if you don't agree with the FAQ excerpt 
> you put on top of the page or if you are simply trying to do the 
> impossible... ;-)

  Supporting *everything* that povray support will, indeed, be an almost
impossible task. Or at least extremely laborious. And also a task which
has to be careful to not to break the usage license of POV-Ray.

  One simple case: Supporting the trace() function will require support
for raytracing *all* possible objects which can be generated with povray.
(As we know, trace() can be used for eg. place objects on the surface of
another object.) Another similar function is inside() (which can be used
to place objects inside another object, for instance). Objects may be
created using a pattern, a pigment or a whole texture declaration, and
they may be created using user-defined functions, so the converter would
have to emulate all of this.
  It may be tempting to use povray's own code for this, but that would
break the usage license, so it's out of question. One would have to
implement tracing of all objects from scratch as well as simulate all
of povray's patterns, pigments and textures.

  There's another simple case which falls in a gray area: rand().
If, for example, objects are placed using rand(), the converter program
would have to use the exact same rand() function as povray uses. While
I suppose one could get express permission to use the exact same function,
it's still a gray area with regard to the usage license...

  Then there are some practical issues. For example, you can create
an infinite non-planar surface with POV-Ray (for example using a poly
object). Since a mesh cannot be infinite, the program will have to
decide on some arbitrary boundaries inside which it will tesselate
the surface in question. It just may happen that the boundaries are
too tight for some scene and that in the result there will be a border
not visible in the original.

  Some polys may be finite, but not bounded. I don't know if there's any
easy way of determining the boundaries of a polynomial, so tesselating
such beasts may be a rather heavy job.

-- 
                                                          - Warp

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