Ron Parker wrote:
> 
> "intervals" is the maximum number of chunks POV will break the ray into for
> purposes of calculating the color of the media.  An interval begins or ends
> at the boundary of the area of illumination of a spot or cylinder light.
	Actually, in MegaPOV, it's the *minimum* number of chunks
(and in standard POV, it's the exact number). Some intervals
do begin or end at the light boundaries, the others are
evenly spaced.

> There's really no reason you should ever have to specify this; POV should be
> able to figure it out for itself, and in fact Nathan has made it do so.
	Right, that's why it's better when set to 1, especially
since iirc method 3 doesn't sample the media near the ends
of the interval (!) and therefore, the more intervals you
have, the less accurate the computations (and the higher the
risk of banding).

> 
> "samples" is the minimum and maximum number of sample points in an interval.
> POV will sample at least the minimum number of points, and if the variance is
> too high will continue sampling until either the variance is low enough or
> the number of samples hits the maximum.
> 
	An additional explanation here:
* in method 1, samples are taken randomly in the interval
until the variance is low enough, or the max has been
reached;
* in method 2, the minimum number of samples are taken
evenly spaced in the interval, then others are taken
randomly like for method 1 (hence the return of the grainy
look when samples max is bigger than min);
* in method 3, the maximum number of samples isn't used.
Samples are first taken evenly spaced like for method 2,
then if two consecutive samples are too different, another
is added in the middle, and so on until they are near enough
or the aa depth has been reached.

		Jerome

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