Path: utzoo!attcan!uunet!tektronix!pogo!jacks
From: jacks@pogo.GPID.TEK.COM (Jack Slingerland)
Newsgroups: comp.lang.postscript
Subject: Re: what about color laser printers?
Summary: "color" as defined in version 49
Keywords: LaserWriter, PostScript
Message-ID: <6505@pogo.GPID.TEK.COM>
Date: 20 Dec 88 18:16:40 GMT
References: <1667@valhalla.ee.rochester.edu> <113@adobe.COM>
Organization: Tektronix Inc., Beaverton, Or.
Lines: 35


Curtis Jackson (jackson@adobe.COM) states:

> Just a bit of picky education:  There is no such thing as "Color Postscript".
> The Postscript [tm] Language from Adobe has always had full color support
> from Day 1.

If we take the red book as  the definition of the language at "Day 1", then
at Day 1 the language allowed for setting a current painting color
(setrgbcolor and sethsbcolr), and for querying the interpreter for the
current color setting (currentrgbcolor and currenthsbcolor).  There was
no provision for color in the raster operators.

In 1988 ("Day 1" + 3 years), Adobe published "PostScript Language Color
Operator Definitions" which defined a new color model (cmyk) and the
following new operators:

         setcmykcolor                  currentcmykcolor
         setcolortransfer              currentcolortransfer
         setblackgeneration            currentblackgeneration
         setundercolorremoval          currentundercolorremoval
         setcolorscreen                currentcolorscreen         
         colorimage (in 5 flavors)

It is this version of PostScript [tm] (implemented in version 49), 
which is meant when it is said that Tektronix's Phaser Interpreter is 
compatible with Color PostScript [tm].

-----------------------------------------------------------------

		Jack Slingerland	(503) 685-3985
                 Graphics Printing & Imaging Division
                     Tektronix, Inc  (MS 63-356)
                PO Box 1000;  Wilsonville, Oregon 97070
 jacks@pogo.GPID.TEK.COM                        ...tektronix!pogo!jacks