Hello there,
Just to clarify on your thoughts, the VRML language is only a file format
for describing 3D objects. There is no magical tie between VRML and OpenGL
other than the fact that most people are writing VRML browsers that use
OpenGL for doing the actual rendering of each object. Of course, you could
just as easily use other rendering languages to build your browser such as
PEX or the rendermorphics library you referred to.
To rephrase your question then, I believe you are asking what is the advantage
of using OpenGL over rendermorphics, if any? The answer is that OpenGL
has much wider acceptance than rendermorphics does. That is, it is
available on more platforms and supported by more hardware companies
than any other realtime 3D rendering language. So, if you were to write
your browser based on OpenGL, you would find porting it to other platforms
a lot easier. If, however, your main concern is speed not portability,
you might really want to use the rendermorphics library to squeeze the
maximum performance out of your hardware. Keep in mind that many companies
are promising cheap fast 3D hardware that will use OpenGL real soon now :-)
Your accelerator which may seem speedy now, could quickly become obsolete.
Will your browser become obsolete too or require a complete rewrite? If
you use OpenGL, you'd probably be able to use new hardware without so much
as a recompile.
If you decide to use rendermorphics, you can at least be careful to build
your browser in a very modular style so that you can easily swap out the
rendering code and replace it with OpenGL rendering code at a later date.
Happy coding,
Daeron
(this letter written by voice)