-- File:	ExtPElS.cdl
-- Created:	Thu Feb 21 18:36:35 1991
-- Author:	Isabelle GRIGNON
--		<isg@topsn3>
---Copyright:	 Matra Datavision 1991


class   ExtPElS from Extrema
    	---Purpose: It calculates all the extremum distances
    	--          between a point and a surface.
    	--          These distances can be minimum or maximum.

uses   	POnSurf  from Extrema,
    	Cone     from gp,
	Pln      from gp,
    	Cylinder from gp,
    	Pnt      from gp,
    	Sphere   from gp,
    	Torus    from gp

raises  NotDone from StdFail,
    	OutOfRange

is
    Create returns ExtPElS;
    
    Create (P: Pnt; S: Cylinder; Tol: Real) returns ExtPElS;
      	---Purpose: It calculates all the distances between a point 
      	--          and a cylinder from gp.
      	--          Tol is used to test if the point is on the axis.

    Perform(me: in out; P: Pnt; S: Cylinder; Tol: Real) 
    is static;

    Create (P: Pnt; S: Pln; Tol: Real) returns ExtPElS;
      	---Purpose: It calculates all the distances between a point 
      	--          and a plane from gp.
      	--          Tol is used to test if the point is on the plane.

    Perform(me: in out; P: Pnt; S: Pln; Tol: Real) 
    is static;


    Create (P: Pnt; S: Cone; Tol: Real) returns ExtPElS;
      	---Purpose: It calculates all the distances between a point 
      	--          and a cone from gp.
      	--          Tol is used to test if the point is at the apex or
      	--          on the axis.

    Perform(me: in out;P: Pnt; S: Cone; Tol: Real)
    is static;
    
    Create (P: Pnt; S: Torus; Tol: Real) returns ExtPElS;
      	---Purpose: It calculates all the distances between a point 
      	--          and a torus from gp.
      	--          Tol is used to test if the point is on the axis.
    
    Perform(me: in out; P: Pnt; S: Torus; Tol: Real)
    is static;

    Create (P: Pnt; S: Sphere; Tol: Real) returns ExtPElS;
      	---Purpose: It calculates all the distances between a point 
      	--          and a sphere from gp.
      	--          Tol is used to test if the point is at the center.
    
    Perform(me: in out; P: Pnt; S: Sphere; Tol: Real)
    is static;


    IsDone (me) returns Boolean
    	---Purpose: Returns True if the distances are found.
    	is static;
    
    NbExt (me) returns Integer
    	---Purpose: Returns the number of extremum distances.
    	raises  NotDone from StdFail
	    	-- if IsDone(me)=False.
    	is static;

    SquareDistance (me; N: Integer) returns Real
    	---Purpose: Returns the value of the Nth resulting square distance.
    	raises  NotDone from StdFail,
    	    	-- if IsDone(me)=False.
    	        OutOfRange
		-- if N < 1 or N > NbPoints(me).
    	is static;

    Point (me; N: Integer) returns POnSurf
    	---Purpose: Returns the point of the Nth resulting distance.
    	raises  NotDone from StdFail,
    	    	-- if IsDone(me)=False.
    	        OutOfRange
		-- if N < 1 or N > NbPoints(me).
    	is static;

fields
    myDone : Boolean;
    myNbExt: Integer;
    mySqDist: Real [4];
    myPoint: POnSurf from Extrema [4];

end ExtPElS;