"Anthony D'Agostino" <sco### [at] spamEcsicom> wrote in message
news:3dee9ab8@news.povray.org...
> The documentation states: "Rather than performing the complex calculations
> that would be required to model a true area light, it is approximated as
an
> array of point light sources spread out over the area occupied by the
> light. The array-effect applies to shadows only. The object's illumination
> is still that of a point source."
>
> The last two sentences are what interest me. They seem to imply that an
> object illuminated by a point light will be exactly the same as one
> illuminated by a very large area light. Is this entirely correct? Assume
> that the scene has just the light and the object, so soft shadows can be
> ignored, unless the object is self-shadowing. I believe a sphere is not
> self-shadowing, so let's say the object is a sphere.
>

This got me interested, see my post in p.b.i


> So the only way to approximate a true area light source with soft shadows,
> is to use an array of area lights -- like the cornell example. Am I right?
>

I think you should mean an array of point lights maybe? Each area light in
the array (especially the ones at the outer edges) would still have the same
problem as a single area light only on a smaller scale (I suppose with
enough ALs in the array, it would be insignificant though, and you can take
advantage of 'jitter'.

-tgq

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