On Mon, 29 Mar 1999 13:18:04 -0500, Anthony Bennett 
	<ben### [at] panamaphoenixnet> wrote:
>I'm sorry, but it just gets on my nerves when people ignore my posts
>completely. You only scratched the surface about how cool it would be
>and you said nothing truly concrete. Could you please look at the link I
>provided and tell me if you think this can be done? I just want a yes or
>no. And I don't think you have to use triangles to do it. It could be
>some sort of derivative of  implicit surfaces or something. Anyway,
>thanks to those who really stuck to the original subject of the post.

I looked at the link you provided.  It describes a method and data
structure for managing the massive number of triangles generated by
displacement mapping.  This, of course, presupposes that you're 
working with meshes.  It does make mention of other papers that discuss
attempts to perform displacement mapping without triangles, but then
notes that those methods require tracing a curved ray, which usually
requires an iterative (read: slow and potentially inaccurate) process.

A footnote to the paper (footnote 1, page 4 of 10) notes that it could
be applied to curved surfaces as well as triangles, but by this I'm 
assuming they mean patches of some sort.  Even if they didn't, you'd
still need to write a subdivision routine for each primitive you would
want to displace - it's probably easier to just write a "create mesh"
routine for each such primitive.

I also note that the method documented in the paper doesn't work as
efficiently with a raytracer that renders a line at a time, as POV does
(and is constrained to do by large chunks of code.)

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