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Re: decorative random colors algorithm

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gernot.hoffmann@hs-emden-leer.de wrote:
> 
> John,
> 
> to be honest, the older version (kind of pastel) looked for me more
> esthetical than the one between (didn't see the last one).

That's pretty much still available, though I forget its exact
parameters. I've uploaded forkosh.com/decorative5.ps that's
a pretty much random "color wheel", which was the version
originally intended for maximum "decorativeness".
By the way, although named .ps, it's eps, see below.

The forkosh.com/decorative4.ps now runs through 0<=h<=360
just once around its entire circumference (rather than
the three times for ngon=3 earlier). That's controlled by
the (new) huesteps=0 attribute for once around, or omit the
huesteps attribute entirely for the original "three times around".
   That's arguably not as decorative, but its intent was
to be a little more informative, in a somewhat decorative way,
or something like that. The older more decorative stuff is still
all available, just by running the cgi with an appropriate
query string eps&attribute1=value1&etc. I haven't "disabled"
any functionality, just added new stuff and demonstrated it.
Using any old file's %title line for the cgi's query string
should reproduce that old file (unless I've goofed).

> Here, *.PS files are automatically converted into PDF by Acrobat.
> If you could send PDF, then everybody could use the free Adobe Reader
> or Acrobat.
> 
> If you used *.EPS instead of *.PS, then we could view them immediately 
> by other Adobe programs (Photoshop, InDesign, Illustrator).

Already done. Just replace that leading ps&etc attribute with eps&etc.
That was actually in the program all along. I just didn't think
to mention it. The only differences are the top two lines,
  1,2c1
  < %!PS-Adobe EPSF-3.0
  < %%BoundingBox: 0 0 612 792
  ---
  > %!PS
and the (absence of the) last line preceding the %%EOF
  465a465  [or some other line#, depending on the graphic]
  > showpage
I hope that's all that's needed. When I originally wrote
the program and read some online pages about ps, that's
all that seemed necessary. So I coded it that way, but
never really checked the correctness of the results
beyond the fact that gv doesn't complain.

> Yes, this HLS<-->RGB conversion is really tricky. Maybe it's only an 
> approximation (I forgot the algorithm), but this dates back perhaps 35
> years, where trigonometric functions were very time consuming. 

Yeah, antique slide rules on ebay sell for a lot these days.
The angles of the rotated rgb axes all seem to be 45 degrees
wrt the sl-plane, but I still couldn't immediately see how
you're getting all the projections so easily. But it's all
hidden in the function, and can be easily changed if needed,
completely transparent to the rest of the program.

> Best regards --Gernot Hoffmann
Thanks again.
-- 
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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