okay, here is why i brought this up since everyone doesn't get it. 
currently, in povray, really big numbers (like that of a realistic sized
sun at realistic distances from the scene) coupled with regular to small
numbers (any really small objects like bugs or whatever) give povray
problems.  plus, creating a circular area light (which is what i meant
in the first place) oriented in the right direction and with enough area
light density (and by the way, i think most direct sunlight can be
treated as parallel in most if not all cases) is computationally
expensive in its current form.  lightwave's 'distant light' is fast!  it
doesn't have to calculate where the source is exactly, there isn't an
area light problem (ex. more lights = slower), and it's a great
approximation to the way the sun acts.  another point of consideration
is in making smaller suns proportionately closer.  for still scenes,
this probably doesn't make much difference and is a good way around the
large/small number problem.  however, for scenes that fly around many
kilometers, it may be noticable that the sun is more like a big
lightbulb since it is closer than it should be.  i know i haven't
explained it much better than before, but is anybody starting to
understand what i'm saying?

Warp wrote:
> 
>   Btw, it's a common misconception that light rays coming from the Sun are
> parallel.
> 
>   Actually the Sun is an area light. Its size is significant and thus the
> rays coming from it are not parallel. Light rays coming from opposite sides
> of the Sun disk hit a point in the Earth at different angles.
> 
>   Thinking about it, there should not be big difference between a circular
> light source with the radius of the Sun at a distance of the Sun from the
> Earth, and a circular light source at 1km of distance and respectively
> smaller radius (so that its apparent size is the same), given that our
> scene is some meters wide.
> 
> --
> main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
> ):_;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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