POV-Ray : Newsgroups : povray.binaries.images : Stock colors and assumed_gamma 1 in POV-Ray 3.6 : Re: Stock colors and assumed_gamma 1 in POV-Ray 3.6 Server Time
3 May 2024 11:02:25 EDT (-0400)
  Re: Stock colors and assumed_gamma 1 in POV-Ray 3.6  
From: Thomas de Groot
Date: 5 Nov 2020 03:04:33
Message: <5fa3b211$1@news.povray.org>
Op 31/10/2020 om 11:52 schreef Ive:
> Oh, just out of curiosity, do you remember where "Ive's macros" are 
> from? At the time I wrote CIE.inc and added a few other function to 
> lightsys I did definitely prefer this xyz_2_xyz style. And I think scRGB 
> wasn't even defined at this time.
> 

Maybe from an "earlier" version of CIE? and/or Lightsys? That seems the 
most logical to me.

In the mean time I reviewed my scene code and added the latest Bald 
Eagle macros to the collection (see image and scene file attached). I 
added all the macros to the scene file. This is what it represents:

(1a) my reference color in linear color space;
(1b) my reference color in standard color space;

(2.1a) Ive's: conversion rgb->srgb of (1a);
(2.1b) idem but with Clipka's saturation/brightness boost added;
(2.2a) Ive's: conversion back srgb->rgb;
(2.2b) idem from the boosted color;
(2.2c) idem but using (1b);

(3.1a) Cousin Ricky's: conversion rgb->srgb of (1a);
(3.1b) idem but with Clipka's saturation/brightness boost added;

(4.1a) Bald Eagle's: conversion rgb->srgb of (1a);
(4.1b) idem but with Clipka's saturation/brightness boost added;
(4.2a) Bald Eagle's: conversion back srgb->rgb;
(4.2b) idem from the boosted color;
(4.2c) idem but using (1b).

These are macros applied indiscriminately. It seems immediately obvious 
that Bald Eagle's macros do not need the saturation/brightness boost, 
except probably where 4.2c is concerned.

I leave it to the experts to judge if this little exercise (which I 
enjoyed doing btw) is of any real use. ;-)

-- 
Thomas


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