From Java Media Framework API's Basic Information Track Computational Science Course CPS616 -- Spring Semester 1999. byByeongseob Ki, Scott Klasky, Nancy McCracken
Scene graph superstructure:
A VirtualUniverse contains everything to be drawn
All Java 3D scene graphs must connect to a Virtual Universe object to be displayed
A Locale defines the origin, in high-resolution coordinates, of its attached branch groups
A scene graph itself starts with BranchGroup nodes
A BranchGroup serves as the root of a subgraph, called a branch group, of the scene graph---only BranchGroup objects can attach to Locale objects