Re: Statement from SGI about Inventor

David Cake (
Fri, 24 Jun 1994 10:36:42 +0800

>While we reserve the right to make changes to the core Inventor
>format, we do not expect to make any such changes in the near future.
>Every Inventor file is required to have a header line identifying the
>version of the format; we will not make changes to the core format
>without incrementing the format version number in the header.
It is quite likely that if VRML takes off, that there might be more VRML
code out there than plain Inventor code after a while. Look at the current
explosive growth of WWW pages. In other words Inventor compatibility is not
necessary to keep VRML alive, only to kick start it. The two will probably
be fairly different by the time VRML 1.0 is finished (presuming that we
start with Inventor), and if SGI change the Inventor format in a strange
incompatible way after that, there is no necessity for the two to stay in
synch. How do SGI feel about this?

>Inventor also has a binary file format that is not documented and is
>intended to be read and written only by applications using the
>Inventor library. The only real advantage that the binary format has
>over the ASCII format is that reading a binary file is faster, since
>less parsing must be done. Binary files are about the same size as
>compressed (using any of the popular compression utilites) ASCII
>files, so transfer time should not be a reason to want to use the
>binary format. We do not intend to make the binary format open.
How do SGI feel about making competing binary formats available?
My feeling is that this is not a particularly important issue - due to the
general state of the net, sending ASCII back and forward is probably a much
better idea than any binary format, and easier to track down
standardisation problems, and implement parsers for. So binary file format
is not an issue except for things like efficient implementation of VRML
servers, and we can always make our own later. It does mean that SGI have
an initial advantage, but not that much of one.

I guess we have our answer. Now we might actually have to look at
Inventor on technical grounds.
David Cake