-- File:	Lin2dTanPer.cdl
-- Created:	Wed Apr  3 11:05:31 1991
-- Author:	Remi GILET
--		<reg@topsn2>
---Copyright:	 Matra Datavision 1991

class Lin2dTanPer

from GccAna

	---Purpose: This class implements the algorithms used to 
	--          create 2d lines tangent to a circle or a point and 
	--          perpendicular to a line or a circle.
    	-- Describes functions for building a 2D line perpendicular
    	-- to a line and:
    	-- -   tangential to a circle, or
    	-- -   passing through a point.
    	-- A Lin2dTanPer object provides a framework for:
    	-- -   defining the construction of 2D line(s),
    	-- -   implementing the construction algorithm, and
    	-- -   consulting the result(s).
        
--inherits Storable from Standard

uses   Pnt2d            from gp,
       Lin2d            from gp, 
       Circ2d           from gp,
       QualifiedCirc    from GccEnt,
       Array1OfReal     from TColStd,
       Array1OfLin2d    from TColgp,
       Array1OfPnt2d    from TColgp,
       Position         from GccEnt,
       Array1OfPosition from GccEnt

raises BadQualifier      from GccEnt,
       OutOfRange        from Standard,
       ConstructionError from Standard,
       NotDone           from StdFail

is

Create(ThePnt    : Pnt2d          from gp;
       TheLin    : Lin2d          from gp) returns Lin2dTanPer;
	---Purpose: This method implements the algorithms used to 
	--          create 2d lines passing through a point and 
	--          perpendicular to a line.

Create(ThePnt    : Pnt2d          from gp;
       TheCircle : Circ2d         from gp) returns Lin2dTanPer
raises ConstructionError;
	---Purpose: This method implements the algorithms used to 
	--          create 2d lines passing through a point and 
	--          perpendicular to a circle.

Create(Qualified1 : QualifiedCirc from GccEnt;
       TheLin     : Lin2d         from gp    ) returns Lin2dTanPer
raises BadQualifier;
-- Raises BadQualifier in case of EnclosedCirc.
	---Purpose: This method implements the algorithms used to 
	--          create 2d lines tangent to a circle and 
	--          perpendicular to a line.

Create(Qualified1 : QualifiedCirc from GccEnt;
       TheCircle  : Circ2d        from gp    ) returns Lin2dTanPer
raises BadQualifier,ConstructionError;
-- Raises BadQualifier in case of EnclosedCirc.
	---Purpose: This method implements the algorithms used to 
	--          create 2d lines tangent to a circle and 
	--          perpendicular to a circle.

-- .........................................................................

IsDone(me) returns Boolean from Standard
is static;
    	---Purpose : Returns True if the algorithm succeeded.

NbSolutions(me) returns Integer from Standard
    	---Purpose : Returns the number of solutions. 
    	-- Raises NotDone if the construction algorithm didn't succeed.
raises NotDone
is static;
 

WhichQualifier(me                                  ;
    	       Index   :     Integer  from Standard;
	       Qualif1 : out Position from GccEnt  )
raises OutOfRange, NotDone
is static;
    	---Purpose: Returns the qualifier Qualif1 of the tangency argument
    	-- for the solution of index Index computed by this algorithm.
    	-- The returned qualifier is:
    	-- -   that specified at the start of construction when the
    	--   solutions are defined as enclosing or outside with
    	--   respect to the argument, or
    	-- -   that computed during construction (i.e. enclosing or
    	--   outside) when the solutions are defined as unqualified
    	--   with respect to the argument, or
    	-- -   GccEnt_noqualifier if the tangency argument is a point.
    	-- Exceptions
    	-- Standard_OutOfRange if Index is less than zero or
    	-- greater than the number of solutions computed by this algorithm.
    	-- StdFail_NotDone if the construction fails. 
        
ThisSolution(me                           ;
    	     Index : Integer from Standard) returns Lin2d from gp
    	---Purpose : Returns the solution number Index and raises OutOfRange 
    	--           exception if Index is greater than the number of solutions.
    	--           Be careful: the Index is only a way to get all the 
    	--           solutions, but is not associated to those outside the 
    	--           context of the algorithm-object.
    	--    Raises NotDone if the construction algorithm 
    	--          didn't succeed.
    	--          It raises OutOfRange if Index is greater than the 
    	--          number of solutions.
raises OutOfRange, NotDone
is static;
   
Tangency1(me                                     ;
          Index         : Integer   from Standard;  
          ParSol,ParArg : out Real  from Standard;
          Pnt           : out Pnt2d from gp      )
    	---Purpose : Returns informations about the tangency point between the 
    	--           result number Index and the first argument.
    	--           ParSol is the intrinsic parameter of the point on the 
    	--           solution curv.
    	--           ParArg is the intrinsic parameter of the point on the 
    	--           argument curv.
    	--           If the first argument is a point ParArg is equal zero.
    	--    raises NotDone if the construction algorithm didn't succeed.
    	--          It raises OutOfRange if Index is greater than the 
    	--          number of solutions.
raises OutOfRange, NotDone
is static;
   

Intersection2 (me                                     ;
               Index         : Integer   from Standard;
               ParSol,ParArg : out Real  from Standard;
               PntSol        : out Pnt2d from gp      )
    	---Purpose : Returns informations about the intersection between the 
    	--           solution number Index and the second argument.
    	--           It returns the first intersection in a case of 
    	--           Lin2dTanPer which is perpendicular to a circle .
    	--           ParSol is the intrinsic parameter of the point on the 
    	--           solution curv.
    	--           ParArg is the intrinsic parameter of the point on the 
    	--           argument curv. Raises NotDone if the construction algorithm 
    	--          didn't succeed.
    	--          It raises OutOfRange if Index is greater than the 
    	--          number of solutions.

raises OutOfRange, NotDone
is static;
   

fields

    WellDone : Boolean from Standard;
    	---Purpose: True if the algorithm succeeded.

    NbrSol   : Integer from Standard;
    	---Purpose: The number of possible solutions. We have to decide 
    	--          about the status of the multiple solutions...

    linsol   : Array1OfLin2d from TColgp;
    	---Purpose: The solutions.

    qualifier1 : Array1OfPosition from GccEnt;
    	---Purpose: The qualifiers of the first argument.

    pnttg1sol   : Array1OfPnt2d from TColgp;
    	---Purpose: The tangency point between the solution and the first 
    	--          argument on the solution.

    pntint2sol   : Array1OfPnt2d from TColgp;
    	---Purpose: The tangency point between the solution and the second 
    	--          argument on the solution.

    par1sol   : Array1OfReal from TColStd;
    	---Purpose: The parameter of the tangency point between the solution 
    	--          and the first argument on the solution.
    
    par2sol   : Array1OfReal from TColStd;
    	---Purpose: The parameter of the tangency point between the solution 
    	--          and the second argument on the solution.

    pararg1   : Array1OfReal from TColStd;
    	---Purpose: The parameter of the tangency point between the solution 
    	--          and the first argument on the first argument.

    pararg2   : Array1OfReal from TColStd;
    	---Purpose: The parameter of the tangency point between the solution 
    	--          and the second argument on the second argument.

end Lin2dTanPer;