-- File:	Geom2dAPI_ProjectPointOnCurve.cdl
-- Created:	Wed Mar 23 15:03:16 1994
-- Author:	Bruno DUMORTIER
--		<dub@fuegox>
---Copyright:	 Matra Datavision 1994


class ProjectPointOnCurve from Geom2dAPI
---Purpose:
-- This class implements methods for computing all the orthogonal
-- projections of a 2D point onto a 2D curve.

uses
    Curve     from Geom2d,
    Curve     from Geom2dAdaptor,
    ExtPC2d   from Extrema,
    Pnt2d     from gp,
    Length    from Quantity,
    Parameter from Quantity

raises
    OutOfRange from Standard,
    NotDone    from StdFail
    
    
is
    Create
	---Purpose: Constructs an empty projector algorithm. Use an Init
    	-- function to define the point and the curve on which it is going to work.
    returns ProjectPointOnCurve from Geom2dAPI;
    
    
    Create(P          : Pnt2d from gp;
    	   Curve      : Curve from Geom2d)
        ---Purpose: Create the projection  of a  point  <P> on a curve
        --          <Curve> 
    	---Level: Public
    returns ProjectPointOnCurve from Geom2dAPI;
    

    Create(P          : Pnt2d     from gp;
    	   Curve      : Curve     from Geom2d;
    	   Umin, Usup : Parameter from Quantity)
        ---Purpose: Create  the projection  of a point <P>  on a curve
        --          <Curve> limited by the two   points of parameter Umin and Usup.
--    Warning
-- Use the function NbPoints to obtain the number of solutions. If
-- projection fails, NbPoints returns 0.    
    returns ProjectPointOnCurve from Geom2dAPI;
    

    Init(me : in out;
    	 P          : Pnt2d from gp;
	 Curve      : Curve from Geom2d)
        ---Purpose: Initializes this algorithm with the given arguments, and
-- computes the orthogonal  projections  of a  point  <P> on a curve <Curve> 
    is static;


    Init(me : in out;
    	 P          : Pnt2d     from gp;
	 Curve      : Curve     from Geom2d;
    	 Umin, Usup : Parameter from Quantity)
        ---Purpose: Initializes this algorithm with the given arguments, and
-- computes the orthogonal projections of the point P onto the portion 
-- of the curve Curve limited by the two points of parameter Umin and Usup.
    is static;


    NbPoints(me)
	---Purpose: return the number of of computed
    	-- orthogonal projectionn points.
    returns Integer from Standard
    ---C++: alias "Standard_EXPORT operator Standard_Integer() const;"
    is static;

    
    Point(me; Index : Integer from Standard)
    returns Pnt2d from gp
	---Purpose: Returns the orthogonal projection
-- on the curve. Index is a number of a computed point.
-- Exceptions
-- Standard_OutOfRange if Index is not in the range [ 1,NbPoints ], where
-- NbPoints is the number of solution points.
    raises
    	OutOfRange from Standard
	
    is static;
    
    
    Parameter(me; Index : Integer from Standard)
    returns Parameter from Quantity
	---Purpose: Returns the parameter on the curve
-- of a point which is the orthogonal projection. Index is a number of a
-- computed projected point.
-- Exceptions
-- Standard_OutOfRange if Index is not in the range [ 1,NbPoints ], where
-- NbPoints is the number of solution points.
    raises
    	OutOfRange from Standard
	
    is static;
    
    
    Parameter(me; Index :     Integer   from Standard;
                  U     : out Parameter from Quantity)
	---Purpose: Returns the parameter on the curve
-- of a point which is the orthogonal projection. Index is a number of a
-- computed projected point.
-- Exceptions
-- Standard_OutOfRange if Index is not in the range [ 1,NbPoints ], where
-- NbPoints is the number of solution points
    raises
    	OutOfRange from Standard
	
    is static;
        
    Distance(me; Index : Integer from Standard)
    returns Length from Quantity
	---Purpose: Computes the distance between the
-- point and its computed orthogonal projection on the curve. Index is a
-- number of computed projected point.
-- Exceptions
-- Standard_OutOfRange if Index is not in the range [ 1,NbPoints ], where
-- NbPoints is the number of solution points.
    raises
    	OutOfRange from Standard
	
    is static;


    NearestPoint(me)
    returns Pnt2d from gp
    	---Purpose:  Returns the nearest orthogonal projection of the point on the curve.
    	-- Exceptions
    	-- StdFail_NotDone if this algorithm fails.
    	---C++: alias "Standard_EXPORT operator gp_Pnt2d() const;"
    raises
    	NotDone from StdFail
    is static;
    
    
    LowerDistanceParameter(me)
    returns Parameter from Quantity
	---Purpose: Returns the parameter on the curve
-- of the nearest orthogonal projection of the point.
-- Exceptions
-- StdFail_NotDone if this algorithm fails.
    raises
    	NotDone from StdFail
    is static;


    LowerDistance(me)
	---Purpose: Computes the distance between the
    	-- point and its nearest orthogonal projection on the curve.
    	-- Exceptions
    	-- StdFail_NotDone if this algorithm fails.
    returns Length from Quantity
 	---C++: alias "Standard_EXPORT operator Standard_Real() const;"
   raises
    	NotDone from StdFail
    is static;
    
    
    Extrema(me)
	---Purpose: return the algorithmic object from Extrema
    	---Level: Advanced
	---C++: return const&
	---C++: inline      
    returns ExtPC2d from Extrema
    is static;
	    

fields

    myIsDone: Boolean from Standard;
    myIndex : Integer from Standard;    -- index of the nearest solution
    myExtPC : ExtPC2d from Extrema;
    myC     : Curve   from Geom2dAdaptor;

end ProjectPointOnCurve;