Re[4]: proposed new Media Type application/iges

Alan Peltzman (peltzmaa@CC.IMS.DISA.MIL)
Wed, 22 Mar 95 13:41:37 EST

IGES Colleagues:

In response to Ed Levinson's question. If 3-D is being put through
as a new MIME type then it seems to make a great deal
of sense to register IGES as a 3-D MIME type.

However, if the 3-D proposal does not pass, then
we can take the fall-back position of registering
IGES as an "image" type. I think it is essential
that IGES be put in the category that most closely
fits its functionality.

I would be very encouraged if 3-D become a MIME type.
Then IGES, VRDL (Virtual Reality Display Language),
PHIGS, and ISO 10303-Part 42 could be appropriately
registered in this category.

It would be unfortunate if IGES were to be put in
a "legacy" MIME type category (like "image" or "application")
just prior to 3-D going online. I would like to see if
3-D passes as a MIME type before we commit ourselves
to putting IGES in an inappropriate category.

- Alan
______________________________ Reply Separator _________________________________
Subject: Re: Re[2]: proposed new Media Type application/iges
Author: "Donald E. Eastlake 3rd" <> at smtp
Date: 03/22/95 01:02 PM

How about the
parameter to the image type? :-)


On Wed, 22 Mar 1995, Ed Levinson wrote:

> Date: Wed, 22 Mar 1995 10:42:09 -0500
> From: Ed Levinson <elevinso@Accurate.COM>
> To: Keith Moore <>
> Cc:, Alan Peltzman <>,
> Linas Vepstas <>,,
> Subject: Re: Re[2]: proposed new Media Type application/iges
> Keith Moore and Mitra posit the following reasons for a 3D
> Content-type.
> One can forward a 2D image to a fax and you can't do that with
> a 3D one.
> 2D viewers exist that handle multiple 2D formats; similarly
> for 3D viewers. Hence different default behaviour or separate
> mailcap entries for 2D/* and 3D/* make sense.
> The problem for me is that these arguements can be made for a
> "spreadsheet" type as well. Perhaps this points to a fundamental
> problem with the MIME audio and image types, the justification for
> them being at the top level is not strong. Finally, I observe that
> there is an implicit identity, image == 2D. Does that need to be?
> Question. Does it make sense to register IGES as application/iges
> while the introduction of a 3D type moves through the IETF? The
> practical experience might shed light on these issues.
> Best.../Ed
> On Tue, 21 Mar 1995 19:19:07 EST Keith Moore wrote:
> > I suspect that 3-D models don't fit well into (2-D) image/*. Can you
> > usefully display a 3-D model with a fax machine? Seems like you at
> > least need to be able to interact with the model so you can change
> > perspective, etc.
> >
> > By definition, *any* new type fits into application/* if it doesn't
> > fit into some other category. The question is, do these types need
> > some special handling beyond application/*?
> On Tue, 21 Mar 1995 16:41:15 PST Mitra wrote:
> > ...
> > I look at this with the question, "What kinds of things can we do to these
> > files", for an image the answers are things like display, scale, convert to
> > another image etc, in many cases a 2D display may be willing to accept an
> > image of any of several sub-types. On receiving an unknown image, launching
> > a generic viewer (like xv) may make sense etc.
> >
> > The same answers apply to the disjoint set of 3D files, for example DXF,
> > RenderWare, VRML, ACE, these describe a 3D object (not neccessarily a
> > particular view on it), many tools can read one of the formats and convert
> > to the others. Common actions include viewing from different angles,
> > rotating, moving through them etc.

Donald E. Eastlake 3rd +1 508-287-4877(tel)
318 Acton Street +1 508-371-7148(fax)
Carlisle, MA 01741 USA +1 703-620-4200(main office, Reston, VA)