> Gavin Bell writes:
> > At the first VAG meeting, SGI was proposing that properties be restricted to
> > a special 'properties' list of a Separator; so, for example, instead of:
> >
(Gavin has heart change which Bernie questions)
A key to object oriented programming (which VRML and Open Inventor sort
of are) is that abstractions should come from the user domain, not the
application domain. A chair object should abstract and present the
elements of a chair from the viswpoint of the sitter, not the chair builder.
Bernie's comments seem to me to come very helpfully from the user
domain. He is looking at the next level up of abstraction, while keeping
a close eye on lower level dstails.
Users (ie application developers or world builders) do not think of scene
graphs, they think of entities like people and vehicles existing in a 3D
space. I believe Open Inventor can be awkward for the higher level user
working at the entity level.
Some stabs stabs have been made with things like node kits, but by an
large the design thinking seems to keep getting pulled back to a thin
abstraction of OpenGL. And OpenGL, while a wonderful user-domain
abstraction of a 3D pipeline, is not a wonderful abstraction for an 3D
application-level programmer to dsal with.
Please, give us an object or entity node, or at least a conceptually
robust equivalent. But watch out for the something-for-everyone
syndrome that seems to be setting in.
Rob Glidden
Soft Press