It should be quite a simple job to adjust the black point for a bitmap to make any shade of grey truly black. It you have a bitmap editor with a levels control, you can adjust the end points of the black-white range of image. At the extreme you can compress the entire brightness range into just black and white (no grey in between), but with a small range you can get a grey scale scan looking pretty black and white.
Footleg On Tue, 19 May 2015 07:35 Bruce <bruce at tomo.co.nz> wrote: > Thanks for asking that question Michael > I have the same problem, but I had not bothered to think about changing the > linework colour. > > I just tried a simpler approach (that leaves the header and grid > coordinates > black). I will use this from now on. > > symbol-colour group all [60] #makes everything grey > colour map-fg [97 86 38] #add some colour > > And check out this code to make the grid grey > > http://therion.speleo.sk/wiki/doku.php/metapost?s[]=change&s[]=grid&s[]=symb > ols#special_symbol_examples > <http://therion.speleo.sk/wiki/doku.php/metapost?s[]=change&s[]=grid&s[]=symbols#special_symbol_examples> > Code to change grid symbols from cross hairs to continuous lines > > Thanks > Bruce > (I don't know how to change the pen colours) > > > -----Original Message----- > From: therion-bounces at speleo.sk [mailto:therion-bounces at speleo.sk] On > Behalf > Of Michael Wasmund > Sent: Tuesday, 19 May 2015 12:00 p.m. > To: therion at speleo.sk > Subject: [Therion] Redefining PENA...PEND to draw lighter > > > Hello, > Does someone have metapost code to redefine PENA...PEND to draw grey > instead > of black? > > Why I need this: > > My survey consists of 80% scanned bitmaps and 20% drawn scraps. > The bitmaps are "grey", not black (can't make them better using image > processing). > The drawn scraps then stand out and look ugly compared to the bitmaps. > > I know how to redefine individual symbols (walls etc.) to be grey instead > of > black, > but rather than redefining a large symbol set I'd rather redefine the PENs > - > if possible. > > Regards, > Michael. > > _______________________________________________ > Therion mailing list > Therion at speleo.sk > http://mailman.speleo.sk/mailman/listinfo/therion > > _______________________________________________ > Therion mailing list > Therion at speleo.sk > http://mailman.speleo.sk/mailman/listinfo/therion > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mailman.speleo.sk/pipermail/therion/attachments/20150519/16bb677d/attachment.html>
