On 16/01/10 02:29, Reactor wrote:
[...]
> Those are artifacts caused by too few samples.  Are you absolutely certain that
> you did modify the right part of the file?  Because settings samples to 1000
> would be extremely slow.  I would expect a samples setting of 100 to be more
> than enough.

Yeah, sorry about that --- I edited my post at the last moment and, of
course, cocked it up. 1000 samples was indeed *agonisingly* slow, but
produced identical results to 100, 60 or 30 samples.

>   Can you post more related code and the version you are using?  I have a
> suspicion involving the use of more than one media per object (sometimes the
> value specified for samples gets reused inappropriately).

In fact, I'm making progress. I put together an isolated test case that
I could post here and, naturally, discovered that it wasn't manifesting
the problem. A bit more investigation revealed that the problem has
nothing to do with my clouds at all --- it's the *atmosphere*.

My planet's atmosphere is another sphere with a media in it; it's
running a fairly complicated function to get the Rayleigh density right
(it's not, but that's another story). The clouds and the atmosphere are
union'd together. It turns out that there's some very odd interaction
between the two. Changing the sampling settings on the *atmosphere*
changes the appearance of the *clouds*.

Are there any gotchas involved in unioning two hollow objects with media
together? Changing the atmosphere sampling method to 1 or 2 makes the
clouds look *really* weird, which is not what I was expecting.

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