POV-Ray : Newsgroups : povray.unofficial.patches : Facets Server Time
2 Sep 2024 12:14:30 EDT (-0400)
  Facets (Message 1 to 4 of 4)  
From: ingo
Subject: Facets
Date: 11 Feb 2000 14:20:58
Message: <8ED7C9C44seed7@204.213.191.228>
From the MegaHelp:
"The facets texture is designed to be used as a normal. Like bumps or 
wrinkles, it is not suitable for use as a pigment. .."

"Not suitable", does this also mean it can't be used as a pigment?
If I try, WinMegaPov gives a rendering error: problem in Evaluate_TPat.

Ingo

-- 
Photography: http://members.home.nl/ingoogni/
Pov-Ray    : http://members.home.nl/seed7/


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From: Chris Huff
Subject: Re: Facets
Date: 11 Feb 2000 15:45:26
Message: <chrishuff_99-3E7119.15463011022000@news.povray.org>
In article <8ED7C9C44seed7@204.213.191.228>, ing### [at] homenl (ingo) 
wrote:

> From the MegaHelp:
> "The facets texture is designed to be used as a normal. Like bumps or 
> wrinkles, it is not suitable for use as a pigment. .."
> 
> "Not suitable", does this also mean it can't be used as a pigment?
> If I try, WinMegaPov gives a rendering error: problem in Evaluate_TPat.

Hmm, bumps just behaves like bozo when used in a pigment, and I often 
use wrinkles as a pigment.
But facets is not defined as an ordinary pattern, the function 
Evaluate_TPat() doesn't know what to do with it when it gets that type. 
It is handled in the surface normal code instead. I don't know how it 
could be used as a pigment or anything else other than a normal...maybe 
it could return a value between 0 and 1 depending on the angle between 
the normal perturbed with "facets" and the actual normal, but it 
wouldn't look like facets. The crackle pattern with "solid" turned on(or 
the blotches pattern) is more useful for that.
I think it should be defined in some way for pigments though, or at 
least have a parse-time error generated when someone tries to use it in 
this way.

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/


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From: Ron Parker
Subject: Re: Facets
Date: 11 Feb 2000 16:00:35
Message: <slrn8a8u3m.v8.ron.parker@ron.gwmicro.com>
On Fri, 11 Feb 2000 15:46:30 -0500, Chris Huff wrote:
>I think it should be defined in some way for pigments though, or at 
>least have a parse-time error generated when someone tries to use it in 
>this way.

Personally, I think facets should be nuked and replaced by a crackle 
warp that warps all points in a voronoi region to the location of the
centroid of that region.  It wouldn't be a complete replacement, because
the facets normal pattern isn't even like other normal patterns, but
I think you could get similar results for most objects without the 
scalability problems facets has (A given facets normal will make bigger 
facets in areas of low curvature and smaller facets in areas of higher 
curvature, so the same pattern applied to spheres of different sizes 
gives different facets.  Applied to a blob, it gives varying sizes of 
facets over the same object.)

-- 
These are my opinions.  I do NOT speak for the POV-Team.
The superpatch: http://www2.fwi.com/~parkerr/superpatch/
My other stuff: http://www2.fwi.com/~parkerr/traces.html


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From: Chris Huff
Subject: Re: Facets
Date: 11 Feb 2000 16:06:14
Message: <chrishuff_99-DB4752.16071811022000@news.povray.org>
In article <slr### [at] rongwmicrocom>, 
ron### [at] povrayorg wrote:

> Personally, I think facets should be nuked and replaced by a crackle 
> warp that warps all points in a voronoi region to the location of the
> centroid of that region. 

Sounds interesting, and probably a good idea. The facets pattern just 
isn't very useful due to it's dependance on the variations of the 
normal...

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/


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