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From: davis@3d.enet.dec.com (Peter Davis)
Newsgroups: comp.lang.postscript
Subject: Re: multiple color fill?
Message-ID: <1991Jun25.142221.29123@engage.pko.dec.com>
Date: 25 Jun 91 14:17:59 GMT
Sender: newsdaemon@engage.pko.dec.com (USENET News Daemon)
Organization: Digital Equipment Corporation
Lines: 21


In article <538@daily-planet.concordia.ca>, sotbill@vax2.concordia.ca writes...
>Is it possible to do gradiant filling in postscript?

Yes, it's possible, but it's not built into the language.  At least, not in
Level 1.

The way to do this is to write a procedure which sets the outline of the area to
be filled as your clip path, and then draws individual bars, circles, or
whatever in gradually varying colors.  In other words, you have to do the
graduation yourself.  You can use various tricks to figure out how wide you want
the bands of color to be, such as figuring out the size of a pixel on the output
device.

In Level 2 PostScript, there's actually a color space for "pattern fills."  I
haven't looked at this closely enough yet to figure out if it will do what you
want.  I think you'll still have to write the looping procedure to draw bands of
different colors, but you'll be able to define it as a fill pattern, so
referring to it will be simpler.

-pd