On 5/5/2011 9:51 AM, Glenn Waldron wrote:
AFAIK, OSG doesn't maintain VBO/EBO bindings as part of its sortable state. So I believe they will be bound and unbound for each Geometry, even if they are shared. Somebody correct me if I'm wrong. (See Geometry::drawImplementation.)
This is my experience as well. OSG binds and unbinds the buffer object per Geometry during draw, and doesn't attempt to minimize this state change.
OSG relies on the underlying OpenGL implementation to do lazy buffer bindings, so that binding a buffer, followed by unbinding a buffer, followed by binding the same buffer again, is handled optimally. However, to my knowledge, OSG doesn't group Geometry objects based on the buffer objects they use, so even if the underlying OpenGL implementation does perform lazy buffer bindings, it's unlikely that OSG is taking maximum advantage of it.
-Paul _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
