POV-Ray : Newsgroups : povray.binaries.scene-files : Dakota Red Granite macro - beta #1 : Re: Dakota Red Granite macro - beta #1.1 Server Time
21 Jun 2024 10:04:58 EDT (-0400)
  Re: Dakota Red Granite macro - beta #1.1  
From: Dave Blandston
Date: 18 May 2021 06:55:00
Message: <web.60a39c8b581f2f6879416a1f607c1b34@news.povray.org>
Thomas de Groot <tho### [at] degrootorg> wrote:
> I think there are two tracks here to consider: (1) the use of 'pitch
> black' in pigments and textures, where the use of 1/256 or 1/257 would
> be the way to go; (2) the use of <0,0,0> in a 'geometrical' construction
> like a height_field or, I suppose, an isosurface or a parametric object
> or whatever, where 'true' zero would be a must. this should be clear
> from the onset in any scene. Height_fields in particular certainly make
> good use of 'true' zero. Approximations should be reserved for
> pigments/textures.

If I may offer a humble opinion/observation, using a value of 1/256 for the
purpose of multiplying the brightness of an object does not make sense (to me,
anyway) for this reason: Assuming the base scene is lit such that a fully-lit
part of an object will have the same approximate output RGB value as the
corresponding RGB value of the input pigment, a value of 1/256 will result in a
pixel value of 0. In my opinion, that should be considered the true base value.
What is the alternative? 1/256 is arbitrary. Why not 1/317? It's not possible to
foresee what value is actually going to be desired.

Also, even the best monitors don't display pure black anyway. Maybe future
technological developments will change that...

Kind regards,
Dave Blandston
Suggested motto: "With POV-Ray anything is possible, but nothing is easy"

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