Hello Thomas,
i only have set ->setDataVariance(osg::Object::DYNAMIC); to the geode, now i also have set it to the shapeDrawable. Should i apply it only to the shapeDrawable or to both?
Data variance only has an effect on subclasses of osg::Drawable and on osg::StateSet (at run time - it has an effect on other nodes for the osg::Optimizer if you use that, but at run time it only effects drawables and statesets).
After this change it draws the first point of my setHeight() changes, any following setHeight() call doesnt paint anything? If i use ->dirtyDisplayList(); on the shapeDrawable directly after calling setHeight() crashes the application.
But you didn't answer the other question, do you call it in the update phase? If you don't pay attention to when you call it, you might be calling it during the cull phase while OSG is trying to draw your height field, so one thread will be trying to draw it while another will be trying to update it and it will crash.
For the changes in height to be visible, either you need to disable display lists completely (setUseDisplayList(false)) or you need to dirty the display list (dirtyDisplayList()). There's no getting around that, if you don't do one of those two things then the old display list will still be used and you won't see any changes you make using setHeight()... Makes sense doesn't it?
For a relatively small height field, the general recommendation is that if you're going to be changing the heights often (say more often than once per second), you should disable display lists completely, or else you'll be spending too much time updating them. But if you're going to be changing the heights less often, then you should keep display lists enabled and call dirtyDisplayList() (from the update phase! say in an update callback on your geode).
But for large height fields, you should probably disable display lists in any case, and perhaps even enable VBOs, if you're using a pretty recent video card, it will be more efficient that way.
Anyways, try the different alternatives out and see for yourself. Hope this helps, J-S -- ______________________________________________________ Jean-Sebastien Guay [email protected] http://www.cm-labs.com/ http://whitestar02.webhop.org/ _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
