-- File:	Lin2dBisec.cdl
-- Created:	Wed Apr  3 11:29:37 1991
-- Author:	Remi GILET
--		<reg@topsn2>
---Copyright:	 Matra Datavision 1991


class Lin2dBisec

from GccAna

	---Purpose: Describes functions for building bisecting lines between two 2D lines.
    	--          A bisecting line between two lines is such that each of its
    	--          points is at the same distance from the two lines.
    	--          If the two lines are secant, there are two orthogonal
    	--          bisecting lines which share the angles made by the two
    	--          straight lines in two equal parts. If D1 and D2 are the
    	--          unit vectors of the two straight lines, those of the two
    	--          bisecting lines are collinear with the following vectors:
    	--          -   D1 + D2 for the "internal" bisecting line,
    	--          -   D1 - D2 for the "external" bisecting line.
    	--          If the two lines are parallel, the (unique) bisecting line is
    	--          the straight line equidistant from the two straight lines. If
    	--          the two straight lines are coincident, the algorithm
    	--          returns the first straight line as the solution.
    	--          A Lin2dTanObl object provides a framework for:
    	--          -   defining the construction of the bisecting lines,
    	--          -   implementing the construction algorithm, and
    	--          -   consulting the result.
        
uses Lin2d           from gp,
     Pnt2d           from gp,
     Array1OfReal    from TColStd,
     Array1OfLin2d   from TColgp,
     Array1OfPnt2d   from TColgp
     
raises OutOfRange        from Standard,
       NotDone           from StdFail

is

Create(Lin1    : Lin2d from gp ;
       Lin2    : Lin2d from gp ) returns Lin2dBisec;

    	---Purpose: Constructs bisecting lines between the two lines Lin1 and Lin2.
        
IsDone(me) returns Boolean from Standard
is static;
    	---Purpose: Returns True when the algorithm succeded.

NbSolutions(me) returns Integer from Standard
raises NotDone
is static;
    	---Purpose: Returns the number of solutions and raise NotDone if 
    	--          the constructor wasn't called before.

ThisSolution(me                           ;
    	     Index : Integer from Standard) returns Lin2d 
    	---Purpose :Returns the solution number Index .
    	--          The first solution is the inside one and the second is the
    	--          outside one.
    	--          For the first solution the direction is D1+D2 (D1 is 
    	--          the direction of the first argument and D2 the 
    	--          direction of the second argument).
    	--          For the second solution the direction is D1-D2.
    	-- 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;
  
Intersection1 (me                                     ;
               Index         : Integer   from Standard;
    	       ParSol,ParArg : out Real  from Standard;
               PntSol        : out Pnt2d from gp      )
    	---Purpose: Returns informations about the intersection point between 
    	--          the result number Index and the first argument.
    	-- 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 point between 
    	--          the result number Index and the second argument.
    	--    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.

    pntint1sol   : 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 Lin2dBisec;