-- File:	Location.cdl
-- Created:	Wed Dec 19 16:35:30 1990
-- Author:	Christophe MARION
--		<cma@topsn3>
-- Modified:    Portage NT 7-5-97 DPF (Standard_EXPORT)
---Copyright:	 Matra Datavision 1990



class Location from TopLoc

        ---Purpose: A Location is a composite transition. It comprises a
        -- series of elementary reference coordinates, i.e.
        -- objects of type TopLoc_Datum3D, and the powers to
        -- which these objects are raised.

uses
    Datum3D             from TopLoc,
    ItemLocation        from TopLoc,
    SListOfItemLocation from TopLoc,
    Trsf                from gp
    
raises
    NoSuchObject      from Standard,
    ConstructionError from Standard
    
is

    Create returns Location from TopLoc;
	---Purpose: Constructs an empty local coordinate system object.
        -- Note: A Location constructed from a default datum is said to be "empty".
	
    Create(T : Trsf from gp) returns Location from TopLoc
	---Purpose: Constructs the local coordinate system object defined
        -- by the transformation T. T invokes in turn, a TopLoc_Datum3D object.
    raises ConstructionError from Standard;

    Create(D : Datum3D from TopLoc) returns Location from TopLoc;
	---Purpose: Constructs the local coordinate system object defined by the 3D datum D.
        -- Exceptions
        -- Standard_ConstructionError if the transformation
        -- T does not represent a 3D coordinate system.
	
    IsIdentity(me) returns Boolean
	---Purpose: Returns true if this location is equal to the Identity transformation.
   	---C++: inline
    is static;
    
    Identity(me : in out)
	---Purpose: Resets this location to the Identity transformation.
 	---C++: inline
    is static;

    FirstDatum(me) returns Datum3D from TopLoc
	---Purpose: Returns    the  first   elementary  datum  of  the
	--          Location.  Use the NextLocation function recursively to access
 	-- the other data comprising this location.
    	-- Exceptions
    	-- Standard_NoSuchObject if this location is empty.
    raises NoSuchObject 
	    ---C++: return const &
	    ---C++: inline
    is static;
    
    FirstPower(me) returns Integer
	---Purpose: Returns   the  power  elevation  of    the   first
	--          elementary datum.
-- Exceptions
-- Standard_NoSuchObject if this location is empty.
    raises NoSuchObject 
 	---C++: inline
    is static;
    
    NextLocation(me) returns Location from TopLoc
	---Purpose: Returns  a Location representing  <me> without the
	--          first datum. We have the relation :
	--          
	--            <me> = NextLocation() * FirstDatum() ^ FirstPower() 
 --  Exceptions
--  Standard_NoSuchObject if this location is empty.
    raises NoSuchObject 
    ---C++: return const &
    ---C++: inline
    is static;

    Transformation(me) returns Trsf from gp
	---Purpose: Returns  the transformation    associated  to  the
	--          coordinate system.
	--          
	---C++: return const &
	---C++: alias "Standard_EXPORT operator gp_Trsf() const;" 
    is static;
    
    Inverted(me) returns Location from TopLoc
	---Purpose: Returns the inverse of <me>.
	--          
	--          <me> * Inverted() is an Identity.
    is static;
	
    Multiplied(me; Other : Location from TopLoc) returns Location from TopLoc
	---Purpose: Returns <me> * <Other>, the  elementary datums are
	--          concatenated.
	--          
	---C++: alias operator*
    is static;
	
    Divided(me; Other : Location from TopLoc) returns Location from TopLoc
	---Purpose: Returns  <me> / <Other>.
	--          
	---C++: alias operator/
    is static;
	
    Predivided(me; Other : Location from TopLoc) returns Location from TopLoc
	---Purpose: Returns <Other>.Inverted() * <me>.
    is static;
	
    Powered(me; pwr : Integer) returns Location from TopLoc
	---Purpose: Returns me at the power <pwr>.   If <pwr>  is zero
	--          returns  Identity.  <pwr> can  be lower  than zero
	--          (usual meaning for powers).
    is static;

    HashCode(me; Upper : Integer) returns Integer
	---Purpose: Returns a hashed value for this local coordinate system.
    	-- This value is used, with map tables, to store and
    	-- retrieve the object easily, and is in the range [ 1..Upper ].
  	---C++:  function call
    is static;
    
    IsEqual(me; Other : Location from TopLoc) returns Boolean
	---Purpose: Returns true if this location and the location Other
    	-- have the same elementary data, i.e. contain the same
    	-- series of TopLoc_Datum3D and respective powers.
    	-- This method is an alias for operator ==.
  	---C++: alias operator ==
    is static;

    IsDifferent(me; Other : Location from TopLoc) returns Boolean
	---Purpose: Returns true if this location and the location Other do
    	-- not have the same elementary data, i.e. do not
    	-- contain the same series of TopLoc_Datum3D and respective powers.
    	-- This method is an alias for operator !=.
  	---C++: alias operator !=
    is static;

    ShallowDump (me; S: in out OStream)
	---Purpose: Prints the contents of <me> on the stream <s>.
	---C++:  function call
    is static;
    
fields
    myItems : SListOfItemLocation from TopLoc;
    
end Location;