The POV documentation on area lights (3.4.7.5) has what seems to be some
ambiguity.  Here's part of the description:
"...it is approximated by 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 word "object" here is somewhat ambiguous. In one or several places in
the documentation, a light source, in general, is referred to as an object
(like any other object.) But in this context, I read it to mean the object
BEING illuminated by the light...although I'm not sure about that. Either
way, I'm a bit confused about this description of an area light being just
a "point source."

To better illustrate what I'm talking about: If I purposely place a typical
object like a box at the location of the area light, but offset the box
slightly, it appears to occlude part of the area light's illumination on
other objects in the scene. (The overall light gets "grainy" or spotty.)
Which leads me to conclude that the box is blocking some of the area light
array. And that it does occupy a certain spatial dimension, not just a
point.

Or does the documentation actually mean, in a literal way, that the
illumination from the area light emanates from just ONE point--as far as
the objects being illuminated are concerned? In other words, do the
illuminated objects in the scene "see" the area light as just a single
point?

Admittedly, these are rather arcane technical questions, probably of no real
importance. But does anyone besides me see the confusion here?

Ken Walker

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