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Re: decorative random colors algorithm

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Nobody <nobody@nowhere.com> wrote:
> On Sun, 01 Jul 2012 12:15:11 +0000, JohnF wrote:
> 
>> However, it still looks a bit "washed out" to my eye. But pushing the
>> exponents (1/3 and 2) too much just "degenerates" the palette to rgb.
>> So maybe my whole idea is just no good. Is there some standard,
>> or not-so-standard, way to choose random rgb numbers that both
>> (a) remain pretty much random, and that also (b) make the resulting
>> image more "vibrant" to the eye (whatever that quantitatively means;
>> I can tell what it subjectively means just by looking)?
> 
> IOW, you want more saturation. Using an HSL or HSV colour space is one
> solution.
> 
>        http://en.wikipedia.org/wiki/HSL_and_HSV

Thanks so much for the useful reference (and the keywords,
which probably would have induced google to cough up more useful
info than I was able to wring out of it myself). Along with
Prof. Hoffmann's http://www.fho-emden.de/~hoffmann/hlscone03052001.pdf
from the preceding followup, that pretty much explains the situation
in terms I can understand.

> If you just want maximum saturation, an alternative is to modify your
> original approach. Set the largest to 1, the smallest to 0, and leave the
> middle one alone. That will give you a uniformly-distributed point on the
> path:
> 
>        Red - Yellow - Green - Cyan - Blue - Magenta - Red
> 
> i.e. all of the edges of the RGB colour cube which don't have black or
> white as an endpoint.
> 
> The original approach doesn't have quite as much saturation (the highest
> and lowest are moved closer to 1.0 and 0.0 rather than all the way),
> while moving the middle one closer to zero results in a bias toward
> red, green and blue.

That sounds perfect and easy, so I tried it out (but it was hard
to write a comment crediting you for the suggestion -- I was tempted
to thank Emily Dickinson:). You can see the results at
  http://www.forkosh.com/decorative.ps   [original]
  http://www.forkosh.com/decorative2.ps  [your suggestion]
(Note: if you already downloaded the original, re-download it,
as one line is now placed slightly differently -- the %%title
is supposed to contain all parameters to reproduce exactly
the same design, but I slightly goofed.)
   Doesn't seem to have much effect on the visual outcome
(though you can diff the two files and easily validate
everything's working as advertised). On the other hand, the
illustrations in Prof. Hoffmann's hlscone section 5 don't show
much visual difference either, so perhaps I'm just expecting
too much improvement. Thanks so much for your help,
-- 
John Forkosh  ( mailto:  j@f.com  where j=john and f=forkosh )

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decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-01 12:15 +0000
  Re: decorative random colors algorithm gernot.hoffmann@hs-emden-leer.de - 2012-07-01 07:59 -0700
    Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-02 07:58 +0000
      Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-02 12:29 +0000
  Re: decorative random colors algorithm Nobody <nobody@nowhere.com> - 2012-07-01 16:25 +0100
    Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-02 08:28 +0000
  Re: decorative random colors algorithm gernot.hoffmann@hs-emden-leer.de - 2012-07-03 01:17 -0700
    Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-03 10:27 +0000
  Re: decorative random colors algorithm gernot.hoffmann@hs-emden-leer.de - 2012-07-03 21:50 -0700
    Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-04 05:15 +0000
      Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-04 08:01 +0000
  Re: decorative random colors algorithm gernot.hoffmann@hs-emden-leer.de - 2012-07-04 02:20 -0700
    Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-04 09:51 +0000
      Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-04 10:59 +0000
        Re: decorative random colors algorithm Wally W. <ww84wa@aim.com> - 2012-07-04 09:03 -0400
          Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-04 13:46 +0000
            Re: decorative random colors algorithm Wally W. <ww84wa@aim.com> - 2012-07-04 12:39 -0400
  Re: decorative random colors algorithm gernot.hoffmann@hs-emden-leer.de - 2012-07-04 07:10 -0700
    Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-04 15:05 +0000
  Re: decorative random colors algorithm gernot.hoffmann@hs-emden-leer.de - 2012-07-04 09:12 -0700
    Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-05 03:18 +0000
      Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-05 05:54 +0000
        Re: decorative random colors algorithm John Forkosh <forkosh@panix.com> - 2012-07-05 12:23 +0000
  Re: decorative random colors algorithm "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-07-05 07:48 +0200
    Re: decorative random colors algorithm JohnF <john@please.see.sig.for.email.com> - 2012-07-05 06:14 +0000
    Re: decorative random colors algorithm Wally W. <ww84wa@aim.com> - 2012-07-05 07:30 -0400

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