-- Created on: 1995-07-18
-- Created by: Modelistation
-- Copyright (c) 1995-1999 Matra Datavision
-- Copyright (c) 1999-2012 OPEN CASCADE SAS
--
-- The content of this file is subject to the Open CASCADE Technology Public
-- License Version 6.5 (the "License"). You may not use the content of this file
-- except in compliance with the License. Please obtain a copy of the License
-- at http://www.opencascade.org and read it completely before using this file.
--
-- The Initial Developer of the Original Code is Open CASCADE S.A.S., having its
-- main offices at: 1, place des Freres Montgolfier, 78280 Guyancourt, France.
--
-- The Original Code and all software distributed under the License is
-- distributed on an "AS IS" basis, without warranty of any kind, and the
-- Initial Developer hereby disclaims all such warranties, including without
-- limitation, any warranties of merchantability, fitness for a particular
-- purpose or non-infringement. Please see the License for the specific terms
-- and conditions governing the rights and limitations under the License.




generic class   GenLocateExtPC from Extrema 
(Curve    as any;
 Tool     as any;    -- as ToolCurve(Curve);
 POnC     as any;
 Pnt      as any;
 Vec      as any )  
					   
    	---Purpose: It calculates the distance between a point and a
    	--          curve with a close point.
    	--          This distance can be a minimum or a maximum.


raises  DomainError  from Standard,
    	TypeMismatch from Standard,
        NotDone      from StdFail
	
private  class PCLocF instantiates FuncExtPC (Curve, Tool, POnC, Pnt, Vec);

is
    Create returns GenLocateExtPC;

    Create (P: Pnt; C: Curve; U0: Real; TolU: Real)
    	returns GenLocateExtPC
    	---Purpose: Calculates the distance with a close point.
    	--          The close point is defined by the parameter value
    	--          U0.
    	--          The function F(u)=distance(P,C(u)) has an extremum
    	--          when g(u)=dF/du=0. The algorithm searchs a zero 
    	--          near the close point.
    	--          TolU is used to decide to stop the iterations.
    	--          At the nth iteration, the criteria is:
    	--           abs(Un - Un-1) < TolU.
    	raises  DomainError;
	    	-- if U0 is outside the definition range of the curve.


    Create (P: Pnt; C: Curve; U0: Real; Umin, Usup: Real; TolU: Real)
    	returns GenLocateExtPC
    	---Purpose: Calculates the distance with a close point.
    	--          The close point is defined by the parameter value
    	--          U0.
    	--          The function F(u)=distance(P,C(u)) has an extremum
    	--          when g(u)=dF/du=0. The algorithm searchs a zero 
    	--          near the close point.
    	--          Zeros are searched between Umin et Usup.
    	--          TolU is used to decide to stop the iterations.
    	--          At the nth iteration, the criteria is:
    	--           abs(Un - Un-1) < TolU.
    	raises  DomainError;
	    	-- if U0 is outside the definition range of the curve.



    Initialize(me: in out; C: Curve; Umin, Usup: Real; TolU: Real)
    	---Purpose: sets the fields of the algorithm.
    is static;

    Perform(me: in out; P: Pnt; U0: Real)
        ---Purpose: the algorithm is done with the point P.
        --          An exception is raised if the fields have not
        --          been initialized.  
    raises TypeMismatch from Standard
    is static;

    IsDone (me) returns Boolean
    	---Purpose: Returns True if the distance is found.
    	is static;

    SquareDistance (me) returns Real
    	---Purpose: Returns the value of the extremum square distance.
    	raises  NotDone from StdFail
	    	-- if IsDone(me)=False.
    	is static;

    IsMin (me) returns Boolean
    	---Purpose: Returns True if the extremum distance is a minimum.
    	raises  NotDone from StdFail
	    	-- if IsDone(me)=False.
    	is static;

    Point (me) returns POnC
    	---Purpose: Returns the point of the extremum distance.
    	raises  NotDone from StdFail
	    	-- if IsDone(me)=False.
    	is static;
    

fields
    myDone : Boolean;
    mytolU : Real;
    myumin:  Real;
    myusup:  Real;
    myF:     PCLocF;

end GenLocateExtPC;