Add compute of tight bounding box to enable better placement of the base plane.
Add compute of tight bounding box to enable better placement of the base plane.


omega-hub/osg,ntoand/osg,koshman86/osg,stmh/osg,XiaoCC/osg,stmh/osg,stmh/osg,ghub/osg,XiaoCC/osg,koshman86/osg,ntoand/osg,koshman86/osg,artoolkit/osg,omega-hub/osg,ntoand/osg,artoolkit/osg,ghub/osg,stmh/osg,koshman86/osg,XiaoCC/osg,ghub/osg,ntoand/osg,omega-hub/osg,XiaoCC/osg,ghub/osg,XiaoCC/osg,omega-hub/osg,artoolkit/osg,artoolkit/osg,stmh/osg