[osg-users] Update Optimization

Paul Martz pmartz at skew-matrix.com
Fri Jul 4 15:54:48 PDT 2008


John -- If you can't upgrade to the new kdtree functionality, I can think of
a couple ways to speed things up off the top of my head.
 
1) If some of the entities are robots, you could pre-compute their
orientation and position.
 
2) Assuming the eyepoint isn't right next to all 300 tanks simultaneously,
take advantage of LOD to avoid doing precise position and orientation
computations.
 
Hope that helps,
   -Paul
 


  _____  

From: osg-users-bounces at lists.openscenegraph.org
[mailto:osg-users-bounces at lists.openscenegraph.org] On Behalf Of John
Burgess
Sent: Friday, July 04, 2008 10:48 AM
To: OpenSceneGraph Users
Subject: Re: [osg-users] Update Optimization


Hi Robert,
 
In the update call back, I use the intersector to compute the height above
terrain and the normal for each tank and position it on the terrain in every
frame. So for 300 tanks, the height and normal computation will be performed
300 times per frame which takes about 700 ms during the update traversal
from the traversal time graphical display. What can be done to reduce the
update time and yet able to achieve my aim of positioning the tanks
correctly on the terrain?
 
Thanks,
John

----- Original Message ----
From: Robert Osfield <robert.osfield at gmail.com>
To: OpenSceneGraph Users <osg-users at lists.openscenegraph.org>
Sent: Saturday, July 5, 2008 12:33:32 AM
Subject: Re: [osg-users] Update Optimization

Hi John,

What exactly is taking all the time?  Your own physics code?
Intersection code?  You have said anything about what you do in the
update other that update positions.

Robert.

On Fri, Jul 4, 2008 at 5:25 PM, John Burgess
<john.burgess at rocketmail.com> wrote:
> Hi all,
>
> My viewer needs to support at least 400 entities running at 30 Hz. My
> entities are all moving tanks and I need to clamp them to the terrain
using
> an update call back in every frame, the frame rate will drop to 3 Hz when
I
> load 300 tanks with the update cycle taking up a huge amount of time. How
> can I achieve 30 Hz for 400 entities and yet be able to clamp them to the
> terrain?
>
> Thanks,
> John
>
> _______________________________________________
> osg-users mailing list
> osg-users at lists.openscenegraph.org
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
>
>
_______________________________________________
osg-users mailing list
osg-users at lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openscenegraph.org/pipermail/osg-users-openscenegraph.org/attachments/20080704/c8b49eae/attachment-0003.htm>


More information about the osg-users mailing list