Donald
On Wed, 22 Mar 1995, Ed Levinson wrote:
> Date: Wed, 22 Mar 1995 10:42:09 -0500
> From: Ed Levinson <[email protected]>
> To: Keith Moore <[email protected]>
> Cc: [email protected], Alan Peltzman <[email protected]>,
> Linas Vepstas <[email protected]>, [email protected],
> [email protected], [email protected], [email protected],
> [email protected], [email protected]
> 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.
>
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