Re: Minor TGS flam>

Mike Heck ([email protected])
Wed, 28 Jun 95 12:11:35 -0700

> Erm, I took the output from DxfToIv and looked at it with Webspace. It cam>
> out fine. I then changed the first line to say VRML 1.0 ascii instead of
> Inventor 1.0 ascii and Webspace barfed at me. This gave me the impression
> that TGS (or perhaps SGI... I
> after the third kernel panic and only use the SGI version now) has an
> Inventor engine in there but is only accepting valid VRML when it is told
> that the file it is reading is indeed VRML and not Inventor. Am I wrong?
> Why would it barf otherwise?

I think one of the SGI folks should respond to this. I haven't used DxfToIv
since it only runs on SGI machines, but I would have expected this to work.
We've taken lots of Inventor files and "converted" them to VRML by changing
the file header (only for testing purposes of course! :-). There is also an
IvToVRML tool that might be useful as a second stage. I've been using Keith
Rule's wcvt2pov program and think it's pretty slick.

[...other stuff deleted...]

> What "crass commercial features" do you support that are not in the
> standard? Have you suggested that they be included in the standard? Is
> there documentation available on the difference between Webspace's VRML and
> the standard? Just what are you talking about? Specifics, please.

The only VRML extensions we support today are the standard<(so to speak)
Inventor nodes. We have not suggested recently that they be re-examined for
inclusion in VRML, but the VRML list did consider all of Inventor when the
features for VRML 1.0 were being defined. An excellent reference for both
what is in Inventor that's not in VRML and (to some extent) why it's not in
VRML *1.0* is Gavin's VRML proposal:

http://www.sgi.com/Technology/Inventor/VRML/VRMLDesign.html

I don't want to list everything here and be accused of "advertising", but
it would make that lany "converted" models render much faster when specified as an
IndexedTriangleStripSet instead of Bag'o'Faces (IndexedFaceSet).

-Mike