Le 13-03-10 04:47, clipka a écrit :
> Am 09.03.2013 20:46, schrieb Alain:
>> Le 2013-03-08 21:40, clipka a écrit :
>>> Am 08.03.2013 23:40, schrieb Alain:
>>>> Out of curiosity, I made a scene to show the array of elementary lights
>>>> in an area_light and found something that I find surprising:
>>>> The outermost elements seem to be about half as bright as the rest, and
>>>> the corner ones dimer still at maybe 1 fourth intensity.
>>>>
>>>> I'm wondering if it's intentional or some oversight.
>
> This is intentional, and especially important for adaptive area lights:
> Think of an NxM area light not as an array of NxM tiles with "lightlets"
> at their centers, but as an array of (N-1)x(M-1) tiles with "lightlets"
> at their corners: Each "lightlet" then represents a quarter of each tile
> that touches it, which adds up to 4/4 tiles for the inner "lightlets",
> but only 2/4 or 1/4 tiles for those at the perimeter.
>
> Thanks for your inquisitiveness nonetheless, as during investigation I
> found a problem with circular area lights, which are not as homogenous
> as they should be (you might already have noticed this, too).
>

It also may have a slight side effect of making the edges of the shadow 
slightly smoother in some cases...

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