Added check for valid pointer
Added check for valid pointer

scrawl/osg,scrawl/osg,jtorresfabra/osg,jtorresfabra/osg,marchelbling/osg,scrawl/osg,scrawl/osg,marchelbling/osg,openscenegraph/osg,tomasthoresen/osg,jtorresfabra/osg,tomasthoresen/osg,openscenegraph/osg,openscenegraph/osg,tomasthoresen/osg,openscenegraph/osg,marchelbling/osg,jtorresfabra/osg,marchelbling/osg,tomasthoresen/osg