Added export to the height field class.
Added export to the height field class.


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