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From: edmoy@violet.berkeley.edu
Newsgroups: comp.sys.mac.programmer
Subject: Re: The New LaserWriter Driver and Gray-Scale bitmaps
Keywords: printing laserwriter grayscale
Message-ID: <23476@agate.BERKELEY.EDU>
Date: 22 Apr 89 22:06:07 GMT
References: <1665@husc6.harvard.edu>
Sender: usenet@agate.BERKELEY.EDU
Organization: University of California, Berkeley
Lines: 57

In article <1665@husc6.harvard.edu> maymudes@husc4.UUCP (David M. Maymudes) writes:
>
>I read on the net that Apple has announced a new version of the LaserWriter 
>Driver.  (Version 6.0, I believe.)  According to the posting, the new driver
>provides support for printing 8/24/32-bit color images on color printers,
>and grayscale images on b/w printers.
>
>Does anyone know exactly what the new driver does and how it is used?  
>
>(A program I'm working on currently does a hand-conversion into Postscript,
>then uses PostScript facilities for dealing with gray-scale images.  It
>doesn't seem terribly portable, and has a tendency to stop working whenever
>a new printer driver comes out.  I didn't write it.)
>
>Disclaimer: I'm not sure the new driver even exists, much less what it does.
>
>
>						--David Maymudes
>
>maymudes%husc4@harvard.ARPA	maymudes@husc4.harvard.edu
>maymudes@husc4.UUCP		maymudes@HARVUNXU.BITNET
>..{seismo, harpo, ihnp4, linus, allegra, ut-sally}!harvard!husc4!maymudes
>davidm@harvarda.BITNET

I've been trying it out experimentally for a day or so.  As the author of
macps/prepfix, I will be making modifications to prepfix to support version
6.0, which has many changes in it from previous LaserPreps.

Anyways, my tests involve using Canvas 2.0 on a color Mac II (under 6.0.3).
My first test (something I'd done before and was dissapointed at) was to
create 5 filled rectangles and labeled with text.  Each rectangle and text
pair was assigned one of the colors black, red, blue, green and white, and
everything appears correctly colored on the screen.

Under LaserWriter 5.2, every rectangle and text prints in black, including
the "white" color!  Under LaserWriter 6.0, which I just installed by dragging
them into the System Folder and going through Chooser, black is black, red,
blue and green are a dark gray color and white is white (and thus invisible).

My second test was to print one of Canvas's color demo drawings, a set of
color car mufflers with light shawdows.  Under LW 5.2, all mufflers come
out black, as does the shadows.  Under LW 6.0, the mufflers are different
shades of gray, while the shadows are a light shade of gray.  It looks
very good.

So it looks like a programs using standard color quickdraw will automatically
come out in gray-scale on a black and white printer.  The new LW 6.0 dialog
box has a button to choose between gray scale and color, so I assume if
you had a color PostScript printer, it would be in color.

Edward Moy				Principal Programmer - Macintosh & Unix
Workstation Support Services		Workstation Software Support Group
University of California
Berkeley, CA  94720

edmoy@violet.Berkeley.EDU
ucbvax!violet!edmoy