The "details" program reads a geometry file that contains four 
separators that represent four different levels of detail.  They 
are inserted into a LOD node and displayed using the Examiner viewer.

Use the left&middle mouse buttons (together) to dolly in and out.
As the objects get closer to/further away from the camera,
the appropriate level is displayed.

You can use the default data provided in "lod.iv", or you
can customize your own.
See "lod.iv" for more details on the required format of the data.
