POV-Ray : Newsgroups : povray.binaries.images : More byproducts of the radiosity discussions... : Re: More byproducts of the radiosity discussions... Server Time
1 Aug 2024 04:16:54 EDT (-0400)
  Re: More byproducts of the radiosity discussions...  
From: Jaime Vives Piqueres
Date: 31 Dec 2008 06:00:20
Message: <495b50c4$1@news.povray.org>

> - By setting nearest_count to 10, no additional samples will be taken
> after the 10th pass whatsoever. In fact, many samples will have been
> taken much earlier.

   I should have warned that "I really don't know what I'm doing" is my
second name... but thanks for the pointer.

> - By taking high error_bound samples first, which are low quality, you
> will reduce the number of low error_bound samples taken.

   Well, here I must admit that I thought I knew what I was doing... ;) What
I wanted was to take first the high error_bound samples, to avoid the 
problem of radiosity coming trough the joints... but perhaps it works 
equally the other way: I must try it.

> - The artifacts you see in the 16b image are not due to the quality of
> the radiosity samples used for that shot, but due to the moment they were
> taken: What we see are the results of final-trace sampling, with the new
> samples affecting their surroundings only in successive rows.

   I think I didn't fully understand this explanation... sorry (not your
fault). But the 16b was done apart in one pass, without loading any radiosity...

> I expect that exactly the same quality - if not even better - can be
> achieved within just two frames by using constant settings as currently
> used in the... hm, let me guesstimate... something like the 6th frame.
> 
> You may also want to try using 1/max(image_width,image_height) as
> pretrace_end, and N/max(image_width,image_height) with N being some power
> of 2 as pretrace_start, and render just a single frame. Try a
> nearest_count of 3 or the like.

   Again, I must try these tips...

> Finally, expect 3.7 radiosity to become better anyway.

   I hope so!

> Oh, and finally finally - keep having ideas like these, 'cause even if
> they don't work as you may think they may still be inspiring. And
> inspiration is the thing most needed with POV's radiosity.

   Thanks: I have lots of weird ideas... and not only abut radiosity, but 
many show to be nonsense after the first tests.

  For example, I also tried something similar to what Holger Karsten tried
with MCPov: rendering many frames with random sample sequences (MegaPOV) and
then averaging them with ImageMagick. It sort of works, but needs too many
frames to get ride of the noise.

   Now, if someone is interested, I had the strange idea that a 
fade_distance  for reflections will help making blurred reflections with 
averaged normals... but I'm unable to test on my head if it will work.

--
Jaime


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