Warp schrieb:
>   It seems that 3.6 and 3.7 are interpreting differently what to do when
> an object has more than one media with differing "samples" settings. The
> question would be whether either one is doing the right thing. If one of
> the medias has been specified to need a higher amount of samples, and if
> povray nevertheless renders it with a lower amount because the other media
> had that lower amount, it would seem to be the wrong thing to do. From those
> timings I deduce that both versions are doing the wrong thing, just in the
> opposite way: One is taking the samples from the first media and the other
> is taking them from the second one, regardless of whether they are different
> from each other or not.

According to the code, POV-Ray does take the settings from what it deems 
the most demanding media (except for the AA threshold, for this it 
searches independently for the smallest value); if all media appear just 
as demanding to POV-Ray, it will pick one more or less at random (the 
behavior in this has probably changed in the wake of changing the 
respective list's data type to a C++ container class).

The problem in this particular case is that POV-Ray's only criterion for 
determining which media is the most "demanding" is the number of intervals.

There is /some/ reason to it: After all, what if a medium has lower 
number of samples but higher number of intervals? What if both min and 
max samples are specified? What if they use different sampling methods? 
Coming up with a good set of rules is not so trivial.

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