"Kenneth" <kdw### [at] earthlinknet> wrote in message 
news:web.442797743e0a76402045a15f0@news.povray.org...
>
> A question (since I may have been doing some things incorrectly up until
> now): Is samples 15 the same as specifying samples(15,15)? In the POV 
> docs,
> there's no mention of using just a single value for it, so I'm curious.

That's my understanding of it, without checking the Doc. One number equates 
to both min., max.

> Also, the docs led me to believe that, with method 3, I needed to actually
> specify intervals 1 rather than leave it out altogether.  Is there a
> difference?

When the default became the new method 3 intervals was reworked (by Nathan 
Kopp, I believe) to default to 1 so it would increase automatically instead 
of being a static 10. Ever since that programming change I've just 
considered it needed specifying only if one of the other methods were 
chosen. I think the confusion is that, as suggested, you should not use 
intervals other than 1 or else you override the automatic increase but many 
times that keyword might exist in your script and you could inadvertantly 
use it incorrectly.

> Can anyone out there give a definitive listing of the various media 
> defaults?

Good question. If I tried to say, it would go like this:

method 1 intervals 10 samples 1,1
method 2 intervals 10 samples 1,1
method 3 intervals 1 samples 1,1

Having now looked at the Doc I see what you meant about that intervals 10 in 
there, other defaults look okay. Obviously, it would not be 10 if the value 
is changed internally the way that newer method type works. However, if it 
did begin at ten and go lower or higher as needed that could explain it 
being 10 there in the Doc. So again, a person would only be using intervals 
1 (usually) if they have the keyword used at all in their media statement to 
signify not to override the inner workings of the program. My memory of what 
was said about it goes like: "increase as needed", so that leaves out any 
decreases downward from 10.

All that said, method 3 really could begin at intervals 10 like the others 
do and I hadn't thought of that. I've remembered it as being 1 internally 
ever since the change was made and I could be mistaken about that. A check 
of the source code would clarify this once and for all.

I took a look at the old source code and I see it shows both the 1 and 10 
based on method type (if I read it correctly) and something about a 
'minsamples' of 2 within the Intervals coding. It's all greek to me, though.
Curiously, I noticed AA depth 3 not 4 as stated in the Doc for method 1, so 
I don't know if that's changed now or another thing that might need 
clarification in the future.
-- 
Bob H  www.3digitaleyes.com
http://3digitaleyes.com/imagery/

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