POV-Ray : Newsgroups : povray.binaries.images : radiosity artefact? Server Time
11 Aug 2024 09:24:09 EDT (-0400)
  radiosity artefact? (Message 1 to 5 of 5)  
From: Bill Hails
Subject: radiosity artefact?
Date: 11 Apr 2004 04:04:24
Message: <4078fc07@news.povray.org>
Anyone got any ideas what might be causing the unpleasant
black speckling on the stonework?

It seems to be keyed to the texture but only occurs with
radiosity turned on and conventional lighting off.

        radiosity {
            Rad_Settings(Radiosity_OutdoorLQ, true, false)
            recursion_limit 2
        }

rendered without aa.

-- 
Bill Hails


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From: Tek
Subject: Re: radiosity artefact?
Date: 11 Apr 2004 06:39:34
Message: <40792066$1@news.povray.org>
Doesn't look like a radiosity error. Looks more like the kind of error you get
with ray-intersection problems, e.g. coincedent surfaces or innaccuracies in
isosurfaces/blobs, etc. Can you render a higher resolution close-up?

-- 
Tek
www.evilsuperbrain.com

"Bill Hails" <bil### [at] europeyahoo-inccom> wrote in message
news:4078fc07@news.povray.org...
> Anyone got any ideas what might be causing the unpleasant
> black speckling on the stonework?
>
> It seems to be keyed to the texture but only occurs with
> radiosity turned on and conventional lighting off.
>
>         radiosity {
>             Rad_Settings(Radiosity_OutdoorLQ, true, false)
>             recursion_limit 2
>         }
>
> rendered without aa.
>
> -- 
> Bill Hails


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From: Samuel Benge
Subject: Re: radiosity artefact?
Date: 11 Apr 2004 13:08:09
Message: <40797B27.5060507@hotmail.com>
Bill Hails wrote:

> Anyone got any ideas what might be causing the unpleasant
> black speckling on the stonework?

Bill, what is that shape made from? Is it a height_field? CSG?

If it's a height_field, I've had the same kind of artifacts even without 
radiosity. Try removing the 'smooth' keyword. I don't know if that will 
help or not, but it's worth a try.

If it's CSG, it might be a problem with coincident surfaces. Try 
translating one object just slightly. I can't see it being that, though.

Hope that helps~

-Samuel Benge


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From: Bill Hails
Subject: Re: radiosity artefact?
Date: 11 Apr 2004 14:26:57
Message: <40798df1@news.povray.org>
Tek wrote:

> Doesn't look like a radiosity error. Looks more like the kind of error you
> get with ray-intersection problems, e.g. coincedent surfaces or
> innaccuracies in isosurfaces/blobs, etc. Can you render a higher
> resolution close-up?
> 

Yeah, you were right, it was just a coincident surface. Sorry to post
such a dumb question without investigating further myself :-(

I now think there may be a few more of them to eliminate.
-- 
Bill Hails


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From: Bill Hails
Subject: Re: radiosity artefact?
Date: 11 Apr 2004 14:42:42
Message: <407991a2@news.povray.org>
Samuel Benge wrote:

> Bill Hails wrote:
> 
>> Anyone got any ideas what might be causing the unpleasant
>> black speckling on the stonework?
> 
> Bill, what is that shape made from? Is it a height_field? CSG?
> 
> If it's a height_field, I've had the same kind of artifacts even without
> radiosity. Try removing the 'smooth' keyword. I don't know if that will
> help or not, but it's worth a try.
> 
> If it's CSG, it might be a problem with coincident surfaces. Try
> translating one object just slightly. I can't see it being that, though.

Thanks, It's CSG, and the problem was just a coincident surface.
Sorry for wasting peoples time :-(

> Hope that helps~
> 
> -Samuel Benge

-- 
Bill Hails


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