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brcain
12-10-2002, 09:52 AM
All,

What is your take on OpenSceneGraph.
See http://www.openscenegraph.org.

We are starting to consider it as an alternative to Vega, VTree, and an in-house scene graph.

Regards,
Ben

cbwan
12-12-2002, 12:37 AM
don't forget to look at opensg(.org)
it has free smp support (openscenegraph has a fee for this), and it's really great!

for what I've seen it seems more extensible, but we mainly took it because of multiprocessor support.
and OpenSG version 1.2 should be out in the first days of 2003!

openscenegraph seems easier to learn though.
I'll give it a try soon, because opensg's node share costs way too much memory comparing to performer. 512mb is not enough anymore!

but I'd prefer to stick with OpenSG, will try to find a way to handle this..

have fun ;)
cb

Robert Osfield
12-12-2002, 02:21 AM
Hi Ben,


Originally posted by brcain:
All,

What is your take on OpenSceneGraph.
See http://www.openscenegraph.org.

We are starting to consider it as an alternative to Vega, VTree, and an in-house scene graph.

Regards,
Ben

Thanks for your interest in the OpenSceneGraph. I'm really not an independent witness, being the project lead, but here goes..

There are a number of ex Vega and VTree users on the OpenSceneGraph mailing list so you're not the first one to follow this trail. And a ex OpenGVS user pointed me at your post this morning http://www.opengl.org/discussion_boards/ubb/smile.gif

IMHO, of all the open source scene graph out there OpenSceneGraph probably is best suited for vis-sim. Its feature set and peformance is competitive with the commerical vis-sim scene graphs, and includes vis-sim loaders such as OpenFlight Terra page, and GEO.


Originally posted by cbwan:
don't forget to look at opensg(.org)
it has free smp support (openscenegraph has a fee for this), and it's really great!


I'm not sure where you got this "for a fee" information from. There isn't a fee for SMP support. Open Producer which supports multi-threaded, multi-pipe configurations is released under the LGPL. Open Procducer is similar in concept to sgi's OpenGL Multipipe SDK, but its cross platform. It will soon be integrated into the core distribution.

for what I've seen it seems more extensible,[/QUOTE]

I am a of course biased, but I very much doubt that OpenSG is more extensible than the OpenSceneGraph. You have to decend to using XML to extend the OpenSG classes because of complications related to the way it does MP support.

One of the OpenSceneGraph's strong points is that is very extensible and crucially *easy* to extend.

Just check out the number of Node Kits that extend it - particles, true type text, and just recently added light points support.

And you have Marco Jez's osgNV for all the latest shader extensions, and lots more happening out in the community.

Cheers,
Robert.

cbwan
12-12-2002, 03:54 AM
> I'm not sure where you got this "for a fee"
> information from.

I had interpreted it from the documentation :

. On your web page you write :
"The library will be made thread safe, for use on multiprocessor systems."

so I looked further in the documentation
and found this :

OpenSceneGraph/doc/plan.html

"Development of commercial add on libraries:

* osgMP - cross platform library for transparently managing mulitpipe and cluster graphics systems. Similar in concept to OpenGL multipipe SDK, except cross platform and with support of graphics clusters."

Not a word on OpenProducer.
So it was not very clear whether there would be free smp support =)
is OpenProducer the new name for osgMP?
or is it another lib?

> I very much doubt that OpenSG is more
> extensible than the OpenSceneGraph.

my mistake, I have to admit I didn't look much in osg's extensibility since it's not my priority for the moment. I was speaking about separation between a node and its core in opensg.

> And you have Marco Jez's osgNV for all the
> latest shader extensions

yep shaders are not yet available in opensg, but should soon http://www.opengl.org/discussion_boards/ubb/wink.gif

anyway smp is very important to us, so I'll try OpenProducer with osg. any link?

I'm very happy you answered the post,
we (I?) need a debate on free scenegraphs!

and I'm sorry if I misinterpreted anything,
it's great to have free scenegraphs!
and two is better than one http://www.opengl.org/discussion_boards/ubb/wink.gif

have fun!
Sébastien Kuntz aka cb

Robert Osfield
12-12-2002, 04:46 AM
Originally posted by cbwan:
> I'm not sure where you got this "for a fee"
> information from.

I had interpreted it from the documentation :

. On your web page you write :
"The library will be made thread safe, for use on multiprocessor systems."

so I looked further in the documentation
and found this :

OpenSceneGraph/doc/plan.html

"Development of commercial add on libraries:

* osgMP - cross platform library for transparently managing mulitpipe and cluster graphics systems. Similar in concept to OpenGL multipipe SDK, except cross platform and with support of graphics clusters."

Not a word on OpenProducer.


Sorry for the confusion, things move fast...

osgMP has become Open Producer, but rather than GLP'd it is now LGPL'd :-)

Open Producer can also work with straight OpenGL applications, a simple adapter adds compatability with OpenSceneGraph.

You'll find Open Producer at:
http://www.andesengineering.com/BlueMarbleViewer/producer_install.html

While the library is still in development, it does already support cross platform multipipe, running on both Sun and sgi's multipipe systems.

Cheers,
Robert.