-- File:	ShapeAnalysis_Shell.cdl
-- Created:	Wed Jun  3 12:06:44 1998
-- Author:	data exchange team
--		<det@nnov.matra-dtv.fr>
---Copyright:	 Matra Datavision 1998


class Shell from ShapeAnalysis 

     ---Purpose: This class provides operators to analyze edges orientation
     --          in the shell.

uses
    Shape    from TopoDS,
    Compound from TopoDS,
    IndexedMapOfShape from TopTools

is

    Clear (me : in out);
    	---Purpose: Clears data about loaded shells and performed checks

    LoadShells (me : in out; shape : Shape from TopoDS);
    	---Purpose: Adds shells contained in the <shape> to the list of loaded shells

    CheckOrientedShells (me : in out; shape   : Shape from TopoDS;
    	    	    	              alsofree: Boolean = Standard_False;
    	    	    	    	      checkinternaledges: Boolean = Standard_False)
    returns Boolean;
    	---Purpose: Checks if shells fulfill orientation condition, i.e. if each
    	--          edge is, either present once (free edge) or twice (connected
    	--          edge) but with different orientations (FORWARD/REVERSED)
    	--          Edges which do not fulfill these conditions are bad
    	--          
    	--          If <alsofree> is True free edges are considered.
    	--          Free edges can be queried but are not bad

    IsLoaded (me; shape : Shape from TopoDS) returns Boolean;
    	---Purpose: Tells if a shape is loaded (only shells are checked)

    NbLoaded (me)  returns Integer;
    	---Purpose: Returns the actual number of loaded shapes (i.e. shells)

    Loaded (me; num : Integer) returns Shape from TopoDS;
    	---Purpose: Returns a loaded shape specified by its rank number.
    	--          Returns null shape if <num> is out of range

    HasBadEdges (me) returns Boolean;
    	---Purpose: Tells if at least one edge is recorded as bad

    BadEdges (me) returns Compound from TopoDS;
    	---Purpose: Returns the list of bad edges as a Compound
    	--          It is empty (not null) if no edge are recorded as bad
 
    HasFreeEdges (me) returns Boolean;
    	---Purpose: Tells if at least one edge is recorded as free (not connected)

    FreeEdges (me) returns Compound from TopoDS;
    	---Purpose: Returns the list of free (not connected) edges as a Compound
    	--          It is empty (not null) if no edge are recorded as free

    HasConnectedEdges (me) returns Boolean;
   	---Purpose: Tells if at least one edge is connected (shared twice or more)

fields

    myShells: IndexedMapOfShape from TopTools;
    myBad   : IndexedMapOfShape from TopTools;
    myFree  : IndexedMapOfShape from TopTools;
    myConex : Boolean;  -- are there or not

end Shell;