Algoritm for RGB Values for Color Wheel

Sannyasin Brahmanathaswami brahma at hindu.org
Mon Sep 12 15:49:59 EDT 2016


@ Scott:

changing constants to

constant color1 = "255,0,0" -- red - primary

constant color2 = "255,64,0" -- red-orange - tertiary
constant color3 = "255,127,0" -- orange - secondary
constant color4 = "255,191,0" -- orange-yellow - tertiary

constant color5 = "255,255,0" -- yellow - primary

constant color6 = "191,255,0" -- yellow- green  - tertiary
constant color7 = "0,255,0" -- green - secondary
constant color8 = "0,191,255" -- green-blue - tertiary

constant color9 = "0,0,255" -- blue - primary

constant color10 = "127,0,255" -- blue-violet - tertiary
constant color11 = "127,0,127" -- violet  - secondary
constant color12 = "191,0,127" -- red-violet- tertiary

We get close to the so-called "official" color wheel. Of course we enter the quicksand territory of subjective choices, CMYK gamut (geared to pigment) vs RGB gamut (light based), using yellow, cyan, magenta as primary apexes instead of RGB 255 on three channels etc.  So the precise logic for setting values starts to blur as we move toward "recognition" colors that people expect.. which are more pigment based. 

The algorithm:

 "go up and down by halves" (255, 127, 64) 

worked in the yellow to orange-red range, but did not work, or works differently, in the blue to violet-red range.  If we wanted to drop back to the pigment based gamut, then we have to find a way to algorithmically "add mud" to all of them… tricky…

Interesting… at any rate… I got what I needed… a lot easier (an less messy!) than the old days when I had to actually mix inks for the KORD!

BR


On 9/12/16, 8:00 AM, "use-livecode on behalf of Sannyasin Brahmanathaswami" <use-livecode-bounces at lists.runrev.com on behalf of brahma at hindu.org> wrote:

    Thanks Scott.. this gets me very close and I can see the pattern.
    
    I can tweak this to get to the "official" formal color wheel which has the three primaries, three secondaries and six tertiaries in proper order
    
    




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