POV-Ray : Newsgroups : povray.binaries.images : landscape testing new radiosity patches [198k] Server Time
8 Aug 2024 10:21:26 EDT (-0400)
  landscape testing new radiosity patches [198k] (Message 1 to 7 of 7)  
From: Christoph Hormann
Subject: landscape testing new radiosity patches [198k]
Date: 26 Aug 2005 16:05:36
Message: <densgm$d64$1@chho.imagico.de>
I already made this scene some time ago but i thought this might be a 
good occasion to post it since we have just released MegaPOV 1.2.1 which 
includes the radiosity patches used.

This image demonstrates the use of the adaptive pretrace and adaptive 
error_bound patches in a large render of a detailed scene.  One major 
problem of such renders is that they tend to be very slow at large size 
since a lot of additional samples are taken in the final pass which also 
results in a raise of memory use.  The adaptive error_bound gives better 
control over this - in this case there were only 19 radiosity samples 
taken in the final pass so you can predict the render time and results 
much better from a small size test render.

The adaptive pretrace can reduce the pretrace time in a scene with large 
areas only requiring very few samples (like the sky here).  However you 
have to use a low pretrace_start to avoid areas to be completely skipped 
by the pretrace.  The pretrace time here was 4 hours (final pass time 
was 13 hours for 6400 x 3600).

The radiosity settings used are:

   radiosity {
     pretrace_start 0.006
     pretrace_end   0.0015
     adaptive 1
     count 100
     nearest_count 3
     error_bound { 0.8 adaptive 1.5, 20 }
     recursion_limit 1
     low_error_factor 0.2
     gray_threshold 0.0
     minimum_reuse 0.015
     brightness 0.85
     always_sample off
   }

Christoph

-- 
POV-Ray tutorials, include files, Landscape of the week:
http://www.tu-bs.de/~y0013390/ (Last updated 24 Jul. 2005)
MegaPOV with mechanics simulation: http://megapov.inetart.net/


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From: Orchid XP v2
Subject: Re: landscape testing new radiosity patches [198k]
Date: 27 Aug 2005 03:33:38
Message: <43101752$1@news.povray.org>
1. That's an increadible image. Are you *sure* that's not a photo?

2. 4 hours FOR THE PRETRACE? :-| You must have A LOT of free time... 
(How long did it take to DESIGN the scene??)


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From: Christoph Hormann
Subject: Re: landscape testing new radiosity patches [198k]
Date: 27 Aug 2005 05:45:02
Message: <depcgs$55j$1@chho.imagico.de>
Orchid XP v2 wrote:
> 1. That's an increadible image. Are you *sure* that's not a photo?
> 
> 2. 4 hours FOR THE PRETRACE? :-| You must have A LOT of free time... 

Actually no - it's just the computer that needs some free time. ;-)

> (How long did it take to DESIGN the scene??)

Not very long - 2-3 days each a few hours.

Christoph

-- 
POV-Ray tutorials, include files, Landscape of the week:
http://www.tu-bs.de/~y0013390/ (Last updated 24 Jul. 2005)
MegaPOV with mechanics simulation: http://megapov.inetart.net/


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From: Hasan3
Subject: Re: landscape testing new radiosity patches [198k]
Date: 27 Aug 2005 06:55:00
Message: <web.43104573fcba7ed669db2b0@news.povray.org>
Very very excellent..


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From: Lonnie
Subject: Re: landscape testing new radiosity patches [198k]
Date: 27 Aug 2005 15:05:02
Message: <web.4310b93afcba7e3b3a698d0@news.povray.org>
Christoph Hormann <chr### [at] gmxde> wrote:
> I already made this scene some time ago but i thought this might be a
> good occasion to post it since we have just released MegaPOV 1.2.1 which
> includes the radiosity patches used.

FanTAStic image, as is all of your work I have seen.  I am curious: do you
use "normal" lighting in these scenes in addition to radiosity?


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From: Sebastian H 
Subject: Re: landscape testing new radiosity patches [198k]
Date: 28 Aug 2005 07:45:50
Message: <4311a3ee$1@news.povray.org>
Christoph Hormann wrote:
> 
> I already made this scene some time ago but i thought this might be a 
> good occasion to post it since we have just released MegaPOV 1.2.1 which 
> includes the radiosity patches used.
> 
> This image demonstrates the use of the adaptive pretrace and adaptive 
> error_bound patches in a large render of a detailed scene.  One major 
> problem of such renders is that they tend to be very slow at large size 
> since a lot of additional samples are taken in the final pass which also 
> results in a raise of memory use.  The adaptive error_bound gives better 
> control over this - in this case there were only 19 radiosity samples 
> taken in the final pass so you can predict the render time and results 
> much better from a small size test render.
> 
> The adaptive pretrace can reduce the pretrace time in a scene with large 
> areas only requiring very few samples (like the sky here).  However you 
> have to use a low pretrace_start to avoid areas to be completely skipped 
> by the pretrace.  The pretrace time here was 4 hours (final pass time 
> was 13 hours for 6400 x 3600).
> 
> The radiosity settings used are:
> 
>   radiosity {
>     pretrace_start 0.006
>     pretrace_end   0.0015
>     adaptive 1
>     count 100
>     nearest_count 3
>     error_bound { 0.8 adaptive 1.5, 20 }
>     recursion_limit 1
>     low_error_factor 0.2
>     gray_threshold 0.0
>     minimum_reuse 0.015
>     brightness 0.85
>     always_sample off
>   }
> 
> Christoph
> 
> 
> ------------------------------------------------------------------------
> 

It's just that most of your images are fantastic...

Sebastian


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From: Stefan Viljoen
Subject: Re: landscape testing new radiosity patches [198k]
Date: 1 Sep 2005 02:35:33
Message: <4316a133@news.povray.org>
Christoph Hormann spake:

> 
> I already made this scene some time ago but i thought this might be a
> good occasion to post it since we have just released MegaPOV 1.2.1 which
> includes the radiosity patches used.
> 
> This image demonstrates the use of the adaptive pretrace and adaptive
> error_bound patches in a large render of a detailed scene.  One major

Very impressive...

-- 
Stefan Viljoen
Software Support Technician / Programmer
Polar Design Solutions

Mobile: (+27) 83 4060854
Tel: (+27) 18 297 1753
Fax: (+27) 18 290 5556 
http://polard.com


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