Path: utzoo!attcan!uunet!husc6!purdue!decwrl!adobe!greid
From: greid@adobe.com (Glenn Reid)
Newsgroups: comp.lang.postscript
Subject: Re: Why is Display Postscript Fast when Printer Postscript is Slow?
Message-ID: <136@adobe.COM>
Date: 21 Dec 88 22:59:07 GMT
References: <1481@helios.ee.lbl.gov> <2164@daisy.UUCP> <133@adobe.COM> <33706@bbn.COM>
Sender: news@adobe.COM
Reply-To: greid@adobe.COM (Glenn Reid)
Organization: Adobe Systems Incorporated, Mountain View
Lines: 20

In article <33706@bbn.COM> cosell@BBN.COM (Bernie Cosell) writes:
>Should one conclude from this that PostScript on "for real" printers (2000dpi
>and up) runs super-duper slow?  [After all, 300 is about 20 times as many
>bits as 72, but 2000dpi is almost a *thousand* times as many points]

Well, no.

It isn't the total number of bits, but more the number of calculations
required.  Think of the "flatness" parameter.  If you're filling a
rectangle, it doesn't matter much how many DPI you have.  If you're
reducing a Bezier curve to a bitmap, you have to do more work if the
resolution is higher.  So yes, it is a factor.  But it is nowhere near
proportional to the density of device space.

Besides, the marking engines run more slowly for higher resolution
printers, so no one notices, right? :-)

Glenn Reid
Adobe Systems
Mountain View