J-S,
I've always used setSupportsDisplayList(false) along with
setuseDisplayList(false). I don't remember why. I'd have to review the osg
geometry code to refresh my memory.
Brian
[EMAIL PROTECTED] wrote: -----
To: OpenSceneGraph Users <osg-users@lists.openscenegraph.org>
From: Jean-Sébastien Guay <[EMAIL PROTECTED]>
Sent by: [EMAIL PROTECTED]
Date: 02/04/2008 10:42AM
Subject: [osg-users] Displaying cables
Hello,
I imagine this is pretty common, I'm just looking for a few hints of how
to optimize things.
Our apps need to display cables (and most of the time, a large number of
them). The cables themselves are controlled by a physical simulation
which gives us a set of transforms for the ends of each segment of a cable.
For now, we are creating some geometry (quad strips, specifically) to
display the cables, and assigning texture coordinates to that geometry,
on the fly. This is needed because if, for example, a cable is
lengthened (because it's being spooled out of a pulley system for
example) the texture shouldn't stretch over it. Similarly, if the
physical simulation subdivides the cable into more segments than it was
in the last frame, we need to have correct texture coordinates to
(hopefully) make the fact that the cable now has more, shorter segments
invisible to the user.
I know the cable display needs to be optimized because if I just set the
cables' nodemasks to 0, the draw times go from 6.6ms to 2.2ms (for the
same view). And there are not *that* many cables... There's a lot of
other geometry in the scene which is still drawn in the 2.2ms time...
So I would appreciate some pointers. I would have assumed quad strips
are pretty fast, so perhaps something else is the problem?
There's the fact that the geometry is dynamic, which could mean that OSG
is trying to recreate display lists each frame, but I tried
setUseDisplayList(false) on the geometry and the cables just did not
display anymore... Is there something else I need to do in that case?
Thanks in advance,
J-S
--
______________________________________________________
Jean-Sebastien Guay [EMAIL PROTECTED]
http://www.cm-labs.com/
http://whitestar02.webhop.org/
_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
This is a PRIVATE message. If you are not the intended recipient, please
delete without copying and kindly advise us by e-mail of the mistake in
delivery. NOTE: Regardless of content, this e-mail shall not operate to
bind CSC to any order or other contract unless pursuant to explicit written
agreement or government initiative expressly permitting the use of e-mail
for such purpose.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
