What OpenGL APIs are available for C++?
Rune Allnor
I've just started playing with OpenGL under C++.
Are there any FAQs or other resources that summarize
the present state of APIs and frameworks? I have found
some comments regarding the Open Inventor API that
suggests it might be more or less obsolete, or at least
not well-maintained:
"The open source version from SGI has since fallen into
obscurity, as SGI has not shown any commitment to do
further development of the library, and seems to spend
little resources even on maintenance."
(From http://en.wikipedia.org/wiki/Open_Inventor )
Rune
jbwest
"Rune Allnor" <all...@tele.ntnu.no> wrote in message
news:3340219c-892f-4780...@r5g2000yqb.googlegroups.com...
Open Inventor is indeed long in the tooth -- altho still popular in some
circles.
Coin3D is an OpenInventor implementation and there are commericial
OpenInventors with lots of extentions & active support. (for $$).
These toolkits are call Scene Graphs -- google for a dizzying array of
offerings.
You need to understand that Scene Graphs (what stuff like OpenInventor,
Performer
Simple Scene Graph
Nvidia Scene Graph
OpenSceneGraph (one of the top ones in Big Vis undustries)
OpenSG (not the same as above)
Xith3D
Irrlicht
OpenRM
VisToolKit
and dozens more... (sorry everyone if I've slighted your favorite!)
Wikipedia lists 32:
http://en.wikipedia.org/wiki/Category:3D_Scenegraph_APIs
These beasties are very different from the OpenGL library. OpenGL is a set
of low-level "down-to-the-iron" api's that do not enforce a particular
behavior or structure to your application. SceneGraphs tend to make you
force your square-ish application into a round-hole scene graph, if you get
my drift. Choosing a Scene Graph tends to establish waht you can and can't
do (easily, if at all) with your application. And, they tend to be so
complex that they do provide you a huge leg up -- if they do what you want
them to. If they don't, they tend to be so big that coercing them to do what
you want make come to take over the work you are trying to do with your
application; and may be broken in the next release. Altho some are lighter
weight and more flxible than others.
Support, viability, capability, cost, licensing, memory load etc are
significant choices to consider with choosing a scene graph. Choosing OpenGL
directly can avoid many of these decisions, but in fairness it takes quite
some expertise to get to the point of doing the subset of things you want
done provided by some scene graphs.
I don't really know of a comprehensive review/comparison of them all -- that
would probably be a huge and ultimately futile undertaking.
Have fun!
jbw
MikeHeck
I have found
> some comments regarding the Open Inventor API that
> suggests it might be more or less obsolete, or at least
> not well-maintained:
>
> "The open source version from SGI has since fallen into
> obscurity, as SGI has not shown any commitment to do
> further development of the library, and seems to spend
> little resources even on maintenance."
That is probably a fair statement regarding the open source version
from SGI. It has not been worked on in quite a while.
However Open Inventor is alive and well and winning new customers as a
commercial product that now includes state of the art OpenGL
rendering, volume rendering, mesh rendering, multi-GPU support, ray
tracing and more. VSG (http://www.vsg3d.com - formerly Mercury
Computer Systems, formerly TGS) took over development from SGI. See
http://www.vsg3d.com/vsg_prod_openinventor.php for more info about the
product.
Regards,
Mike