-- File:	PTopLoc.cdl
-- Created:	Wed Mar  3 15:51:14 1993
-- Author:	Remi LEQUETTE
--		<rle@phobox>
-- Update:      fma
---Copyright:	 Matra Datavision 1993


package PTopLoc 

	---Purpose: The  PTopLoc     package      describes persistent
	--          structures for 3D local coordinate systems.
	--          
	--          The  class Datum3D describes  an  elementary local
	--          coordinate system.   It is a linear transformation
	--          (Trsf  from  gp).   The  transformation  is  rigid
	--          (Rotation +  Translation).
	--          
	--          The private    class  ItemLocation represents   an
	--          elementary  local   coordinate   system  (Datum3D)
	--          raised to  an Integer power  elevation. It is used
	--          to link coordinate systems in a Location.
	--          
	--          The  class Location  describes a local  coordinate
	--          system.   It   is  a  chain   of  elementary local
	--          coordinate systems raised to power elevations. The
	--          Location keeps track  of how the coordinate system
	--          was built.

uses

    Standard,
    gp

is
    class Datum3D;
    -- inherits Persistent from Standard
	---Purpose: Persistent elementary local coordinate system.
	
    private class ItemLocation;
    -- inherits Persistent from Standard
	---Purpose: Persistent class  used to  implement Locations.
	
    class Location;
    -- inherits Storable from Standard
	---Purpose: Storable composite local coordinate system.

end PTopLoc;