larry@csccat.UUCP (Larry Spence) (01/23/90)
I would like to solicit opinions on Display PostScript (DPS) from both
users and non-users. When DPS was first announced, there was a big
flurry of information, news, etc. It seemed like a viable contender.
Lately, however, it looks like NeXT machines (remember?) are the only
thing out there that's actually using DPS in a shipping product. I
recall that DEC was going to adopt DPS, too, but I haven't heard any
more about that for a while. I'm sure Adobe has a long list of vendors
who "have pledged their support," "are developing," etc., but I want
to know if anything is out there that I can buy and evaluate.
I've read the DPS reference materials, so I'm somewhat familiar with
user paths, etc. What I'd like to see is some real-world feedback
from people who are USING the DPS system in a non-trivial fashion.
What's fast? What's slow? What do you like/dislike? How much memory
do you need to display a medium-complexity illustration (e.g., the
"Golfer" demo) with user paths? I saw a demo of a drawing app on the
NeXT machine at Seybold that was sloooooooww... and the excuse was
made that "well, it's running on top of DPS, so that slows it down some."
I've heard that Illustrator is being ported to the NeXT machine, but
it's been a while and nothing has been shipped (that I know of). I would
expect Adobe to get Illustrator running on the NeXT ASAP, in order to
show off DPS the way Mac Illustrator showed off what you could do with
printer PostScript.
At any rate, I just noticed that DPS doesn't seem to be getting much press
anymore, and wondered if some consensus had been reached on its usability,
speed, etc. Also, I read that Phoenix is already working on a DPS clone!
Any info on that?
--
Larry Spence
larry@csccat
...{texbell,texsun,attctc}!csccat!larrysritacco@hpdml93.HP.COM (Steve Ritacco) (01/24/90)
Digital is including DPS in UWS 2.2 which should be out any day now. It is implemented as an extension to X.
kent@godzilla.pa.dec.com (Christopher A. Kent) (01/24/90)
I'm the project leader for the integration of Display PostScript and X under Ultrix, so I feel compelled to respond :-) We're shipping product now -- DPS is a standard part of Ultrix as of UWS2.2. You should be able to order it from DECdirect. The X servers contain an extension that allows you to itnermix X and DPS imaging calls on any X drawable (window or pixmap). This was described in a talk at the 1989 X conference. Performance is ... well, it's really not bad at all. Of course, it depends a lot on what processor you run it on. I have a DECstation 3100 on my desk, and DPS is truly a wonder to behold. It's not as fast as X, by any means - if you can do something in X and DPS, you should do it in X, because X tends to be closer to the hardware in our implementation. But there are things that you can't do in X, and doing them in DPS isn't painful. (I don't have a lot of numbers right now, but the last time I measured just text speed, I got up to about 240 ppm. This may or may not be an interesting number. I'll be doing more measurements soon.) I've written a few programs using X and DPS, and they compliment each other well. For example, DPS doesn't have XOR, but X does, so I can image into a Pixmap with DPS and then use CopyArea to copy to the window in XOR mode... Adobe have announced that they will port Illustrator to our platform as well. They also released the specs for the extension on the MIT R4 tape. I'd be really interested in hearing about Phoenix's clone! Chris Kent Western Software Laboratory Digital Equipment Corporation kent@decwrl.dec.com decwrl!kent (415) 853-6639