On 11 Feb 98 15:59:39 GMT, "Tristan Wibberley"
<tri### [at] compaqcom> wrote:

>I think it is backwards, but it depends on what hybrid is.
>
>it sends rays from the camera, finds which surface it hits first, checks
>that against light sources directly (doesn't send out lots more rays) for
>specular, phong and diffuse, and sends out two more rays for refraction and
>reflection.

Only two things I'd add:  

(1) Specular doesn't mean the same thing to most people that it does
to POV-Ray.  The 'specular' parameter to the finish statement in POV
does not control specular reflection; that is controlled by the
'reflection' parameter.  'specular' controls the size of specular
highlights.  The specular you are talking about is the computation of
those highlights.

(2) POV also traces to each light source to determine shadowing, so it
does trace one additional ray per light source for each intersection
with a diffuse surface (more for area lights), but it doesn't handle
refraction or reflection for those rays.

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