-- File:	MAT_Zone.cdl
-- Created:	Thu May 27 11:12:20 1993
-- Author:	Yves FRICAUD
--		<yfr@phylox>
---Copyright:	 Matra Datavision 1993



class Zone from MAT 

	---Purpose: 
	--          Definition of Zone of Proximity of a BasicElt :
        --          ----------------------------------------------
        --          A Zone of proximity is the set of the points which are
        --          more near from the BasicElt than any other.
        --          
    
inherits 

    TShared from MMgt

uses
    Arc            from MAT,
    Side           from MAT,
    SequenceOfArc  from MAT,
    BasicElt       from MAT,
    Node           from MAT
is

    Create returns mutable Zone from MAT;
    
    Create(aBasicElt : BasicElt from MAT)
        --- Purpose: Compute the frontier of the Zone of proximity.
    returns mutable Zone from MAT;
    	
    Perform(me : mutable ; aBasicElt : BasicElt from MAT)
        --- Purpose: Compute the frontier of the Zone of proximity.
    is static;
    
    NumberOfArcs(me) 
	--- Purpose: Return the number Of Arcs On the frontier of <me>.
    returns Integer
    is static;

    ArcOnFrontier (me ; Index : Integer)
	--- Purpose: Return the  Arc number <Index>  on the frontier.
	--  of  <me>.
    returns Arc
    is static;
    
    NoEmptyZone (me)
	--- Purpose: Return TRUE if <me> is not empty .
    returns Boolean
    is static;
    
    Limited(me)
    	--- Purpose: Return TRUE if <me> is Limited.
    returns Boolean
    is static;
    
    NodeForTurn(me ; 
                anArc     : Arc      from MAT ;
                aBasicElt : BasicElt from MAT ;
		aSide     : Side     from MAT )
    returns Node from MAT
    is static private;
    
fields
    frontier  : SequenceOfArc from MAT;
    limited   : Boolean        from Standard;
end Zone;