Hi all,

I have a scene that would take some 280 hours to render with
radiosity/antialiasing, so I'd like to find a way of splitting it into smaller
segments and rendering each segment separately.  Is there a way to do it?

 - If I just render each segment, I get severe banding.

 - If I turn off antialiasing, save a radiosity file, and load the file for use
with antialiasing, I get very poor results. (I thought this would work better.)

 - I assume that httpov won't help, right?

Any suggestions?

Thanks.

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>  - If I turn off antialiasing, save a radiosity file, and load the file for use
> with antialiasing, I get very poor results. (I thought this would work better.)

   I use this technique often, and I get good results with 3.6 (see for 
example my kitchen scene: it was rendered across several computers).

   I suppose you are not using the beta for this... so, perhaps the problem 
is with the load_file settings: remember you have to use the same settings 
for error_bound, nearest_count and recursion_limit, not just load_file.

   Hope this helps...

--
Jaime

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JH nous apporta ses lumieres en ce 2008/02/19 09:26:
> Hi all,
> 
> I have a scene that would take some 280 hours to render with
> radiosity/antialiasing, so I'd like to find a way of splitting it into smaller
> segments and rendering each segment separately.  Is there a way to do it?
> 
>  - If I just render each segment, I get severe banding.
> 
>  - If I turn off antialiasing, save a radiosity file, and load the file for use
> with antialiasing, I get very poor results. (I thought this would work better.)
> 
>  - I assume that httpov won't help, right?
> 
> Any suggestions?
> 
> Thanks.
> 
> 
> 
> 
When using save_file/load_file, you must keep all radiosity settings unchanged 
exept:
In the final pass use: pretrace_start 1 pretrace_end 1 always_sample 0

All other settings MUST remain the same.

-- 
Alain
-------------------------------------------------
You know you've been raytracing too long when you've gained twenty pounds 
sitting at the computer, but can't tell because your beard covers your stomach.
Taps a.k.a. Tapio Vocadlo

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JH schrieb:
> Hi all,
> 
> I have a scene that would take some 280 hours to render with
> radiosity/antialiasing, so I'd like to find a way of splitting it into smaller
> segments and rendering each segment separately.  Is there a way to do it?

Since it has been mentioned that certain settings have to be kept the 
same when separating pretrace and render - this is not the case for 
most.  In fact i think only recursion_limit must not be modified when 
reusing radiosity data.

In some cases it is a good idea to selectively change certain settings 
to avoid discontinuities between separately rendered tiles. 
always_sample is the obvious and documented one.

The general approach to avoid radiosity sampling in the final pass is to 
  take a lot of samples in the pretrace (by using low error_bound, maybe 
high nearest_count and possibly adapting minimum_reuse).  pretrace_end 
has to be sufficiently low to actually take all those samples of course 
(and the pretrace render resolution has to be sufficient for that of 
course).  In the final renders you need to adapt all those settings to 
mostly avoid further samples (to completely avoid them is hardly 
possible though).

-- Christoph

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