-- File:	Law_Composite.cdl
-- Created:	Fri Mar 29 10:39:22 1996
-- Author:	Laurent BOURESCHE
--		<lbo@phylox>
---Copyright:	 Matra Datavision 1996


class Composite from Law inherits Function from Law

	---Purpose: Loi  composite constituee  d une liste  de lois de
	--          ranges consecutifs.
	--          Cette implementation un peu lourde permet de reunir
	--          en une seule loi des portions de loi construites de 
	--          facon independantes (par exemple en interactif) et 
	--          de lancer le walking d un coup a l echelle d une 
	--          ElSpine. 
	--          CET OBJET REPOND DONC A UN PROBLEME D IMPLEMENTATION
	--          SPECIFIQUE AUX CONGES!!!

uses
    Laws from Law,
    Array1OfReal    from TColStd,
    Shape           from GeomAbs
      
raises OutOfRange from Standard   
 
is

    Create returns mutable Composite from Law;
    ---Purpose: Construct an empty Law
    
    Create (First, Last : Real; 
    	    Tol :Real)
	---Purpose: Construct an empty, trimed Law
    returns mutable Composite from Law;   
    
    Continuity(me) returns Shape from GeomAbs
    is redefined static;
    
    NbIntervals(me; S : Shape from GeomAbs) returns Integer
	---Purpose: Returns  the number  of  intervals for  continuity
	--          <S>. May be one if Continuity(me) >= <S>
    is redefined static;
    
    Intervals(me; T : in out Array1OfReal from TColStd; 
    	          S : Shape from GeomAbs)
	---Purpose: Stores in <T> the  parameters bounding the intervals
	--          of continuity <S>.
	--          
	--          The array must provide  enough room to  accomodate
	--          for the parameters. i.e. T.Length() > NbIntervals()
    raises
    	OutOfRange from Standard 
    is redefined static;
    	
    Value(me: mutable; X: Real from Standard)
    ---Purpose: Returns the value at parameter X.
    returns Real from Standard;

    D1(me: mutable; X: Real from Standard; F,D: out Real from Standard);
    ---Purpose: Returns the value and the first derivative at parameter X.
              
    D2(me: mutable; X: Real from Standard; 
       F,D, D2: out Real from Standard);
    ---Purpose: Returns the value, first and second derivatives 
    --          at parameter X.
        
    Trim(me; PFirst, PLast, Tol :Real from Standard) returns Function
    
    ---Purpose:   Returns a  law equivalent of  <me>  between
	--        parameters <First>  and <Last>. <Tol>  is used  to
	--        test for 3d points confusion.
	--        It is usfule to determines the derivatives 
	--        in these values <First> and <Last> if 
        --        the Law is not Cn.          
    is redefined static;    
    

    Bounds(me: mutable; PFirst,PLast : out Real from Standard);
    ---Purpose: Returns the parametric bounds of the function.

    Prepare(me: mutable; W : in out Real from Standard)
    ---Purpose: Set the current function.
    is static private;

    ChangeElementaryLaw(me: mutable; W : Real from Standard)
    ---C++: return &
    returns mutable Function from Law
    ---Purpose: Returns the elementary  function of the composite used
    --          to compute at parameter W.
    is static;

    ChangeLaws(me : mutable)
    ---C++: return &
    returns Laws from Law
    is static;

    IsPeriodic(me) 
    returns Boolean from Standard
    is static;

    SetPeriodic(me : mutable) 
    is static;

fields

first     : Real from Standard;
last      : Real from Standard;
curfunc   : Function from Law;
funclist  : Laws from Law;
periodic  : Boolean from Standard;
TFirst    : Real from Standard;
TLast     : Real from Standard;
PTol      : Real from Standard;

end Composite;