Jim Charter <jrc### [at] msncom> wrote:
> This is done using isosurface's

  Somehow I have always had a problem with this answer (to the question
"can I bend an object" or similar). There are several reasons for this.

  Firstly, and most importantly, the answer is, strictly speaking,
incorrect. You cannot take any given existing POV-Ray object and somehow
magically bend it "using isosurfaces". Isosurfaces cannot modify existing
objects in any way.
  What you would have to do in order to simulate this is to remodel your
entire object using isosurface functions. This is not always even
possible, and in many cases even when possible it's prohibively
laborious. With some object it doesn't even make any sense, such as
with meshes.

  Secondly, it's not the best solution in all cases nor the most efficient.
For example, if you want to bend a mesh or a heightfield it's usually
much easier and a lot more efficient to just move the vertex points
(assuming you have the vertex points and you can change them with
either POV-SDL or an external program; with heightfields you usually
can use the heightfield macros in the POV-Ray include library).
  Sometimes, when bending simple primitives, it's much more efficient
to model the bent result instead of trying to bend the original
(typical example: bending a cylinder is better done with a torus
segment).

  Thirdly, although this is completely irrelevant and only a question
of semantics, you are not truely "bending" an isosurface: You are
creating a new isosurface function which looks like a bent version
of the original

  In any case, I think it would be much better to answer like:
  "One possible solution is to model your object using isosurface
functions. Isosurfaces can be bent easily."

-- 

                                                          - Warp

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