Kenneth <kdw### [at] earthlinknet> wrote:
> What *is* surprising though, is that the large highlight on the sphere is so
> smooth, when using the light grid; I would have expected multiple, small and
> discreet highlights. (Perhaps there are, but they appear to blend together
> quite well.) An interesting and useful discovery, for me.

  POV-Ray uses the phong reflection model
(http://en.wikipedia.org/wiki/Phong_reflection_model) for highlights,
and the whole idea of this model is that it "blurs" the reflection of
the light source on the surface of the object.
  If you have many such blurred reflections close together, of course
they will form a uniform mass.

> But given that the light grid is casting multiple *distinct* shadows, while
> the area light is creating "jittered" shadows from all(?) of its lights,
> shouldn't the area light produce much smoother shadowing?  (Although, I
> admit, your experiment seems to prove me wrong there.)

  The area_light is not jittered in my example scene. Both examples
should produce identical shadows (except for the tiny differences
produced by 'adaptive').

  There's no visible banding because there are so many point lights
in both cases (10x20). If the camera was moved close enough of one of
the shadow borders then some banding could become visible in both cases.

-- 
                                                          - Warp

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