POV-Ray : Newsgroups : povray.newusers : question on radiosity Server Time
29 Jul 2024 16:25:13 EDT (-0400)
  question on radiosity (Message 1 to 2 of 2)  
From: JYR
Subject: question on radiosity
Date: 16 May 2005 18:50:00
Message: <web.4289229fb7f0ce326a3607400@news.povray.org>
Hi all!
I'd like to know if i'm missing something about the way radiosity works,
especially the effect of the "pretrace_end" parameter.  I'm in the
impression that the lower it is, the longer the pretrace step, obviously.
But, otoh, more and better radiosity values are being gathered during
pretrace, allowing the final pass to be done with more relaxed parameters
(such as a lower "count", a higher "adc_bailout", etc...), and thus to be
completed faster.  For instance, let's say your pretrace takes 10 min
instead of 2, but the final pass takes 12 hours instead of 24, for a fairly
complex scene, that is.

Now, the docs tend to say that lowering "pretrace_end" enhances quality at
the mere expense of speed...

Since i'm still fairly new at POV, i'd appreciate your thoughts on the
subject.  Thanks !

JYR


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From: Warp
Subject: Re: question on radiosity
Date: 16 May 2005 20:06:37
Message: <4289358d@news.povray.org>
JYR <jyr### [at] hotmailcom> wrote:
> Hi all!
> I'd like to know if i'm missing something about the way radiosity works,
> especially the effect of the "pretrace_end" parameter.  I'm in the
> impression that the lower it is, the longer the pretrace step, obviously.
> But, otoh, more and better radiosity values are being gathered during
> pretrace, allowing the final pass to be done with more relaxed parameters
> (such as a lower "count", a higher "adc_bailout", etc...), and thus to be
> completed faster.  For instance, let's say your pretrace takes 10 min
> instead of 2, but the final pass takes 12 hours instead of 24, for a fairly
> complex scene, that is.

> Now, the docs tend to say that lowering "pretrace_end" enhances quality at
> the mere expense of speed...

> Since i'm still fairly new at POV, i'd appreciate your thoughts on the
> subject.  Thanks !

  I don't see anything wrong in your interpretation.

  What was your question anyways?-)

-- 
                                                          - Warp


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