From: portuesi@tweezers.esd.sgi.com (Michael Portuesi)
Newsgroups: comp.sys.sgi
Subject: Re: What to use? GL or motif in development?
Date: 29 Sep 92 16:04:01 GMT
Organization: Silicon Graphics, Inc.  Mountain View, CA


In article <1a87etINN2l1@werple.apana.org.au>, hunter@werple.apana.org.au writes:
> 
> My brother and I are developers.
> We have just become proud owners of an Indigo  What a nice
> piece of hardware. We have set out to develop some animation
> utilities.  We have started our own file format for storeing
> and playing animations.  Its working well. We are now at the
> stage that we want to develop some USER INTERFACES.
> 
> What should we use?  GL or Motif?  This will be using GL for
> the animation playback but we have a number of problems.  GL
> does not have a widget library AND

There are at least three widget sets for GL which are publically
available that I'm aware of, and probably more.  First, there's
Mark Overmar's FORMS library, which has been extensively discussed
in this newsgroup.  Secondly, there's the NASA Panel Library,
which is also available in the public domain.  Finally, there's
our own Showcase Developer's Option.  This is the source code for
IRIS Showcase 2.0, which includes a widget library built on GL.

However, I recommend that you use some sort of X-based approach
for your user interface controls, combined with GL to do the
real work of your application.  The main reason why I make this
recommendation is because that is the direction SGI is heading
with OpenGL.  Under OpenGL, all windowing, event handling, and
colormap management is left to the host windowing system.
OpenGL concerns itself only with rendering and animation.  All
of the current GL-based widget libraries, along with your
user interface code, will have to be ported to work with OpenGL.
However, if you develop an application now which uses X for the
user interface portion combined with GL for rendering, your
migration to OpenGL will be trivial.  SGI already supports this
style of development with its current developer's offerings.

Finally, I recommend that you consider using Motif for developing
the user interface portion of your application.  Motif is
officially supported by SGI for user interface development.  It
will produce an application which is consistent with the overall
look and behavior of our system as well as provide portability
to other X-based platforms.  Motif will also provide you with an
application whose looks and behavior are very similar to those
offered by Microsoft Windows NT.  This is significant, as it will
ease the amount of redesign your user interface will require
should you decide to port to that platform in the future (see
below).

> its possible in the future
> Sun may be able to do the type of stuff SGI can and well if we
> do it in X, there would be much less development/port time
> involved.

Not only must you consider X portability issues when moving
your code to another platform, you must consider GL issues as
well.  OpenGL will be available on several different platforms,
as well as non-X based platforms such as Windows NT.  It might
very well be that you want to base your migration path as much
as possible around OpenGL, simply because the potential audience
for your product on OpenGL-based systems might be much greater
than a custom port to a Sun system (OpenGL will be available for
Sun from third parties).

> What do people think and what does SGI themself suggest.

I thought that our suggestions were pretty well spelled out
in the developer's literature, but the above is a pretty fair
statement of SGI's official position.

--
Michael Portuesi   Silicon Graphics, Inc.   portuesi@sgi.com
Newsgroups: comp.sys.sgi