Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!news.glorb.com!news-out.readnews.com!news-xxxfer.readnews.com!panix!not-for-mail From: JohnF Newsgroups: comp.graphics.algorithms Subject: Re: decorative random colors algorithm Date: Wed, 4 Jul 2012 09:51:10 +0000 (UTC) Organization: PANIX Public Access Internet and UNIX, NYC Lines: 57 Message-ID: References: <5c2486fa-f347-4268-a34e-8eec3b5b8394@googlegroups.com> NNTP-Posting-Host: panix3.panix.com X-Trace: reader1.panix.com 1341395470 21955 166.84.1.3 (4 Jul 2012 09:51:10 GMT) X-Complaints-To: abuse@panix.com NNTP-Posting-Date: Wed, 4 Jul 2012 09:51:10 +0000 (UTC) User-Agent: tin/2.0.0-20110823 ("Ardenistiel") (UNIX) (NetBSD/5.1.2 (i386)) Xref: csiph.com comp.graphics.algorithms:918 gernot.hoffmann@hs-emden-leer.de wrote: > Reply for July 4, 2012: > > your decorative graphic looks really nice, congratulations! I hope you looked (literally) just now, because the originally uploaded version was mistakenly using different random l,s values for each line (I'd flipped an if/then/else clause). It's now fixed, and the sample's using constant l=0.5, s=1.0. And I've added a %comment after each setrgb showing the corresponding h,l,s values, just to be sure. The correct sample graphic now replaces the original erroneous one, at forkosh.com/decorative4.ps and now shows a nice color fan as expected. And, of course, the online cgi is corrected and replaced, too. Sorry about that. > Using stepwise rendering instead of smooth shading, which requires > PostScript 3, has one disadvantage: > Do you observe in Acrobat thin white lines between the segments? Actually, I've just been using gv, which shows your stepwise rendering quite nicely. I'll have to try acrobat when I get to a box that has it. > These are artefacts created by Acrobat, trying to interpolate a segment > boundary with respect to a white background. Two solutions: > 1) Uncheck 'Smooth lineart' in Acrobat. But then the whole image looks > pixelated. > 2) Render twice. First pass with e.g. 17 segments, second pass with > 100 segments. The second pass interpolates as well, but with respect > to an almost correct background. > All my CIE-Diagrams are rendered twice. Okay, I'll put that on my to-do list. I think I can modify your code myself to deal with an N1 and an N2. And I guess the constraint is to pick them relatively prime, or something like that, so no two boundaries coincide. > If you've nothing else to do, you may have a look here: > http://www.fho-emden.de/~hoffmann/casamunsell24062012.pdf Excellent. You can never be too rich, or too thin, or have too many pictures of public toilets. Actually, your "rosetta stone" german/english page gave me an opportunity to try to remember my one year of college german (and three of french). I've spent several months in france, so have whatever french I know fairly permanently imprinted. But only a few days in germany, so couldn't even remember how to ask where to find ... the public toilet (now I can just point to the picture). > Best regards -- Gernot Hoffmann Ditto, thanks so much. -- John Forkosh ( mailto: j@f.com where j=john and f=forkosh )