Added command line arguments to Viewer constructor, and added meaningful error message when no 3d image is provided
Added command line arguments to Viewer constructor, and added meaningful error message when no 3d image is provided


git-svn-id: 23b6355f2bb369032457de4eb5f713ee134f73a8@8784 16af8721-9629-0410-8352-f15c8da7e697

joevandyk/osg,joevandyk/osg,joevandyk/osg,joevandyk/osg,joevandyk/osg