CenterStage Object Class:  OffsetSurface
Subclass of: SurfaceFromSurface
Requires reference to a Surface object

The OffsetSurface class lets you generate offset surfaces from any
given Surface object.  The offset surface is generated by moving the
original surface a certain distance long its normal direction.

The OffsetSurface class supports all the directives of the
SurfaceFromSurface class (other than the Function directive), plus the
following:

    Offset d

	This specifies the distance to offset the new surface from the
	original surface.
