-- Created on: 1992-03-27
-- Created by: Isabelle GRIGNON
-- Copyright (c) 1992-1999 Matra Datavision
-- Copyright (c) 1999-2014 OPEN CASCADE SAS
--
-- This file is part of Open CASCADE Technology software library.
--
-- This library is free software; you can redistribute it and/or modify it under
-- the terms of the GNU Lesser General Public License version 2.1 as published
-- by the Free Software Foundation, with special exception defined in the file
-- OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
-- distribution for complete text of the license and disclaimer of any warranty.
--
-- Alternatively, this file may be used under the terms of Open CASCADE
-- commercial license or contractual agreement.

generic class ZerParFunc from IntImp
    (ThePSurface     as any;
     ThePSurfaceTool as any)


inherits FunctionSetWithDerivatives from math			       

	---Purpose: this function is associated to IWalking
	--          it's the definition of the line F(x,y,z)=0 
	--          where x=X(u,v),y=Y(u,v),z=Z(u,v)

uses Pnt                from gp,
     Dir                from gp,
     Vec                from gp,
     Dir2d              from gp,
     ConstIsoparametric from IntImp,
     Array1OfReal       from TColStd,
     Vector             from math,
     Matrix             from math

raises UndefinedDerivative from StdFail,     
       ConstructionError   from Standard
is

    Create 
    	---Purpose: Raises Construction Error
    	--          
    	returns ZerParFunc from IntImp;

    Create( S1,S2 : ThePSurface )

    	returns ZerParFunc from IntImp;


    NbVariables(me)

    	returns Integer from Standard

    	is static;


    NbEquations(me)

    	returns Integer from Standard

    	is static;


    Value(me : in out;X : in  Vector from math;
                      F : out Vector from math)

    	returns Boolean from Standard
    	is static;


    Derivatives(me : in out;X : in  Vector from math;
                            D : out Matrix from math)

    	returns Boolean from Standard
    	is static;


    Values(me : in out;
           X: in  Vector from math;
           F: out Vector from math; D: out Matrix from math)

    	returns Boolean from Standard
    	is static;

    
    ComputeParameters(me : in out; 
                      ChoixIso: ConstIsoparametric from IntImp; 
                      Param: Array1OfReal from TColStd;
                      UVap,BornInf,BornSup,Tolerance : out Vector from math)
    is static;

    
    Root(me)

    	---Purpose: returns somme des fi*fi

    	returns Real from Standard
	---C++: inline

    	is static;
    

    Point(me)

    	returns Pnt from gp
	---C++: inline

    	is static;
    

    IsTangent(me : in out; UVap : Vector from math;
    	    	    	   Param : out Array1OfReal from TColStd;
    	    	    	   BestChoix :  out ConstIsoparametric from IntImp)

    	returns Boolean from Standard
    	is static;
    

    Direction(me)

    	returns Dir from gp
	---C++: inline

    	raises UndefinedDerivative from StdFail
    	is static;
    

    DirectionOnS1(me)

    	returns Dir2d from gp
	---C++: inline

    	raises UndefinedDerivative from StdFail
    	is static;


    DirectionOnS2(me)

    	returns Dir2d from gp
	---C++: inline

    	raises UndefinedDerivative from StdFail
    	is static;
    

    AuxillarSurface1(me)

    	returns ThePSurface
	---C++: return const&
	---C++: inline

    	is static;


    AuxillarSurface2(me)

    	returns ThePSurface
	---C++: return const&
	---C++: inline

    	is static;

    
fields

    surf1      : Address from Standard; --- ThePSurface;
    surf2      : Address from Standard; --- ThePSurface;
    pntsol1    : Pnt     from gp; --point solution=milieu(pntsol1,pntsol2)
    pntsol2    : Pnt     from gp;
    f          : Real    from Standard[3];  -- equations
    compute    : Boolean from Standard;     --indicateur si tangence calculee
    tangent    : Boolean from Standard;     --indicateur si tangente
    tgduv      : Real    from Standard[4] ; --composante en u,en v de la
                   -- tangente ds plan tg du 1 ier et 2ieme caro
    dpuv       : Vec     from gp[4];        -- dp/du,dp/dv  sur 1ier et 2 ieme
                                            -- caro
    chxIso     : ConstIsoparametric from IntImp; -- indicateur sur l'iso 
                                                 -- constante
    paramConst : Real from Standard; -- parametre de l iso

    ua0,va0,ua1,va1 : Real from Standard; -- surf1 
    ub0,vb0,ub1,vb1 : Real from Standard; -- surf2  
    ures1,ures2,vres1,vres2 : Real from Standard; -- U et V Resolution
    
end ZerParFunc;