Path: utzoo!attcan!uunet!husc6!m2c!applix!scott
From: scott@applix.UUCP (Scott Evernden)
Newsgroups: comp.sys.amiga
Subject: Re: A Modest Proposal (IFF QuickDraw)
Message-ID: <703@applix.UUCP>
Date: 18 May 88 14:47:58 GMT
References: <4607@super.upenn.edu> <15634@uflorida.cis.ufl.EDU>
Reply-To: scott@applix.UUCP (Scott Evernden)
Organization: APPLiX Inc., Westboro MA
Lines: 36

In article <15634@uflorida.cis.ufl.EDU> tws@beach.cis.ufl.edu () writes:
>In article <4607@super.upenn.edu> ranjit@eniac.seas.upenn.edu.UUCP (Ranjit Bhatnagar) writes:
>|The problem:
>|	We don't have a standard for the transfer of "structured
>|graphics,"
>
>I think HP has a standard for their plotters which does quite a few of the
>things you are talking about.  Also Postscript is great for describing pics.

I was waiting for someone to say HPGL.  Pleez, you CANNOT describe a picture
with HPGL; you can merely render it.  The same is true of CGM and NAPLPS and
PostScript and many others mentioned here.  There is no concept of "objects"
in any of these.  Attempting to derive structured graphics data from these
formats is an exercise in AI.

If you study something like Adope Illustrator, you will see that even the
inventors of PostScript do not use it, per say, to store structured graphics
information.  Illustrator cannot import random PostScript files.  What they
use are a set of PostScript DEFs made up to cutely "contain" the structured
graphics info which they have decided they needed.  You would have to clearly
define these if you intend to promulgate PostScript as the interchange vehicle.

The problem with attempting to come up with a universally accepted standard
is that you need to get everyone to agree to it- if the standard doesn't
account for the types of information which are critical to my CAD application
(say 3D or sheared bitmaps, for example), then I'm likely not to use it.
This is why ANSI and ISO have had so much trouble agreeing on and getting
everyone to use CORE, GKS, PHIGS, etc., etc.     etc.

You need facilities to describe grouping, layers, fillets, constraints, etc.
This is the stuff of Modelling.  Information regarding clipping, viewports,
etc., is the stuff of Viewing/Imaging, which is a very different beast.

The folx in comp.graphics would probably be able to enlighten us all...

-scott