draw {surf1 surf2} - Draws the cutplane.  Surf1 and surf2 are
          optional and refer to the gsf library ids of two map objects
          which are surfaces.  If surf1 and surf2 are specified then
          the cutplane is only draw between the two surfaces.

	on - Sets the cutplane as active.

	off - Sets the cutplane as inactive.

	state - Return the state of this object.  On is returned if
          the cutplane is active and false is returned otherwise.

	set_rot x y z - Set the rotation for this cutplane.  X, y and
          z are floating point values.
	
	set_trans x y z - Set the position of this cutplane.  X, y and
          z are floating point values.

	get_rot - Get the rotation for this cutplane.  A three
          element list is returned with x, y and z components in the
          first three entries.

	get_trans - Get the position of this cutplane.  A three
          element list is returned with x, y and z components in the
          first three entries.