David Curtis wrote:
> 
> Questions, questions, questions, ...
> 
> I've just read from the docs that POV converts the bicubic patch into
> triangles. My question is why? It seems obvious that it must have something
> to do with computation time, and the fact that there is no great advantage
> to spending the time calculating a intersection point for every ray. Does
> that sound right?

Yes.

A bicubic patch would have to be represented by a sixth-degree polynomial.
There are methods to calculate ray-surface intersections with a sixth-
degree surface, but they are slow and imprecise.  In most cases a bicubic
patch, with u_steps and v_steps set to three, provides just as good an
end product, but renders far more quickly.

Regards,
John

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