Am 14.03.2018 um 03:21 schrieb Kenneth:

> Yes indeed, that does work. But the funny thing about the current bug is that
> the slowdown only seems to occur with these values:
> 
> brightness:  <= .020
> adc_bailout (for radiosity): >= .01 but < .05 (a small range, actually)
> recursion_limit: *anything* (1 to 20)
> 
> Whereas, an adc_bailout of .009 solves everything; that value doesn't have to be
> any lower, it seems.

Oh the fun of it!

The thing is even more complicated: Try adc_bailout 0.005 for snickers.


Your newest observations made me look again, and it turns out, the whole
thing isn't actually a logical bug: There had alwayas been measures in
place to prevent the problem from happening.

But alas! Those measures suffer from precision problems: One value that
should be /at least/ adc_bailout + EPSILON is passed around with the
same precision as colour values (i.e. single precision, as opposed to
double precision like most math stuff), causing it to be rounded,
sometimes ending up /smaller than/ adc_bailout.

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