Re: [Algorithms] FW: [CsMain] Scene Graphs

[Stephen J B. <sj...@li...>]

On Wed, 6 Sep 2000, Jonathan Wight wrote:

> >> So where does Inventor and the *.iv format fit into this now that (I
> >> believe) it has become an open-source environment?
> > 
> > There are dozens of OpenSourced scene graph API's out there.
> > Inventor becomes yet another.  There are dozens of file formats
> > out there - .iv becomes yet another (and it's essentially just
> > VRML anyway - IIRC)
> > 
> > Adding another to the existing pile doesn't make for standardization.
> 
> Would one size fit all? I have my own set of requirements for a scene graph,
> didn't find anything out there that suited these requirements - which is why
> I'm forced to write my own. I don't think it is possible to create scene
> graph library and make it as generically useful as for example the C++ STL.
 
I know what you mean (I've written my own scene graphs too)...but the
point of my earlier (L-O-N-G) post was that when things like this
initially appear, everyone feels like they could do better writing
to a lower level and doing it themselves - but as time progresses,
we'll get faster machines, better scene graph API's and there will
come a point where (just as with C++ compilers) it's just better
to use a standard API than roll your own for each new project.

If there was a standard SG API, then there would eventually be
hardware to accellerate it, lots of loaders for standard file
formats, we could have standardized collision detection
libraries, physics libraries...those things are not reasonably
possible currently because there is no standard SG API for them
to work with.

Once all those things exist, I think you'd be much more inclined
to accomodate the (hopefully few) limitations of the SG in order
to reap the benefits of working at a higher level abstraction.

This is precisely the state we were at when everyone was
writing pixels into frame buffers and *thinking* about going
to a standard rendering API rather than writing their own
rasterizers for each new project.  There were the exact same
concerns about (say) OpenGL being not *quite* as flexible as
a renderer you could write yourself - and it was lower in
performance.  Then hardware that could make use of OpenGL
came about and over about a year, everyone forgot about
writing their own rasterizers anymore.

Perhaps we just aren't ready for that next step up yet.
I happen to think that the time is about right.

----
Science being insufficient - neither ancient protein species deficient.

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