-- File:	 ConicToBSplineCurve.cdl
-- Created:	 Thu Oct 10 11:26:44 1991
-- Author:	 Jean Claude VAUTHIER
---Copyright:	 Matra Datavision 1991, 1992





deferred class ConicToBSplineCurve   from Convert

        ---Purpose: Root class for algorithms which convert a conic curve into
    	--  a BSpline curve (CircleToBSplineCurve, EllipseToBSplineCurve,
        --  HyperbolaToBSplineCurve, ParabolaToBSplineCurve).
    	-- These algorithms all work on 2D curves from the gp
    	-- package and compute all the data needed to construct a
    	-- BSpline curve equivalent to the conic curve. This data consists of:
    	-- -   the degree of the curve,
    	-- -   the periodic characteristics of the curve,
    	-- -   a poles table with associated weights,
    	-- -   a knots table with associated multiplicities.
    	-- The abstract class ConicToBSplineCurve provides a
    	-- framework for storing and consulting this computed data.
    	-- The data may then be used to construct a
    	-- Geom2d_BSplineCurve curvSuper class of the following classes :
        --  This abstract class implements the methods to get the geometric
        --  representation of the B-spline curve equivalent to the conic.
        --  The B-spline is computed at the creation time in the sub classes.
        --  The B-spline curve is defined with its degree, its control points
        --  (Poles), its weights, its knots and their multiplicity.
        --  All the geometric entities used in this package are defined in 2D
        --  space.
        --  KeyWords :
        --  Convert, Conic, BSplineCurve, 2D.

uses Array1OfInteger      from TColStd,
     Array1OfReal         from TColStd,
     HArray1OfInteger     from TColStd,
     HArray1OfReal        from TColStd,
     HArray1OfPnt2d       from TColgp,
     ParameterisationType from Convert,
     Pnt2d                from gp
     

raises  OutOfRange        from Standard,
        ConstructionError from Standard 
        

is

  Degree (me)   returns Integer   is static;
    	---Purpose: Returns the degree of the BSpline curve whose data is
    	-- computed in this framework.

  NbPoles (me)  returns Integer   is static;
    	---Purpose: Returns the number of poles of the BSpline curve whose
    	-- data is computed in this framework.
    
  NbKnots (me)  returns Integer   is static;
    	---Purpose: Returns the number of knots of the BSpline curve whose
    	-- data is computed in this framework.
  
  IsPeriodic(me) returns Boolean  is static;
    	--- Purpose: Returns true if the BSpline curve whose data is computed in
    	-- this framework is periodic.
  
  Pole (me; Index : Integer)   returns Pnt2d
        --- Purpose : Returns the pole of index Index to the poles table of the
    	-- BSpline curve whose data is computed in this framework.
    	-- Exceptions
    	-- Standard_OutOfRange if Index is outside the bounds of
    	-- the poles table of the BSpline curve whose data is computed in this framework.
     raises OutOfRange
     is static;


  Weight (me; Index : Integer)    returns Real
        --- Purpose : Returns the weight of the pole of index Index to the poles
    	-- table of the BSpline curve whose data is computed in this framework.
    	-- Exceptions
    	-- Standard_OutOfRange if Index is outside the bounds of
    	-- the poles table of the BSpline curve whose data is computed in this framework.
     raises OutOfRange
     is static;


  Knot (me; Index : Integer)   returns Real
        --- Purpose : Returns the knot of index Index to the knots table of the
    	-- BSpline curve whose data is computed in this framework.
    	-- Exceptions
    	-- Standard_OutOfRange if Index is outside the bounds of
    	-- the knots table of the BSpline curve whose data is computed in this framework.
     raises OutOfRange
     is static;


  Multiplicity (me; Index : Integer)    returns Integer
        --- Purpose : Returns the multiplicity of the knot of index Index to the
    	-- knots table of the BSpline curve whose data is computed in this framework.
    	-- Exceptions
    	-- Standard_OutOfRange if Index is outside the bounds of
    	-- the knots table of the BSpline curve whose data is computed in this framework.
     raises OutOfRange
     is static;

  
  Initialize (NumberOfPoles, NumberOfKnots, Degree : Integer);
  
  BuildCosAndSin(me ;
    Parametrisation   :  ParameterisationType       from Convert ;
      --
      -- allowed parameterisation are TgtThetaOver2 and RationalC1
      -- will raise otherwise 
    CosNumerator      : in out HArray1OfReal        from TColStd  ;
      --  Array has the following dimensions :
      --  <1, NbPoles> without multiplying by the weights

    SinNumerator      :  in out HArray1OfReal       from TColStd  ;
      --  Array has the following dimensions :
      --  <1, NbPoles> without multiplying by the weights
    Denominator       :  in out HArray1OfReal       from TColStd  ;
      -- Array has the following dimension
      -- <1, NbPoles>
    Degree            :  in out  Integer            from Standard ;
    Knots             :  in out HArray1OfReal       from TColStd  ;
    Mults             :  in out HArray1OfInteger    from TColStd) 
    raises ConstructionError 
    -- see above
    is static ;
    -- builds a full periodic circle
    -- 
  BuildCosAndSin(me; 
    Parametrisation   :  ParameterisationType       from Convert ; 
    UFirst            :  Real                       from Standard ;
    ULast             :  Real                       from Standard ;
    CosNumerator      : in out HArray1OfReal        from TColStd  ;
      --  Array has the following dimensions :
      --  <1, NbPoles> without multiplying by the weights

    SinNumerator      :  in out HArray1OfReal       from TColStd  ;
      --  Array has the following dimensions :
      --  <1, NbPoles> without multiplying by the weights
    Denominator       :  in out HArray1OfReal       from TColStd  ;
      -- Array has the following dimension
      -- <1, NbPoles>
    Degree            :  in out  Integer            from Standard ;
    Knots             :  in out HArray1OfReal       from TColStd  ;
    Mults             :  in out HArray1OfInteger    from TColStd) 
    raises ConstructionError
    is static ;

fields

  poles      : HArray1OfPnt2d    is protected;
  weights    : HArray1OfReal     is protected;
  knots      : HArray1OfReal     is protected;
  mults      : HArray1OfInteger  is protected;
  degree     : Integer           is protected;
  nbPoles    : Integer           is protected;
  nbKnots    : Integer           is protected;
  isperiodic : Boolean           is protected;

end ConicToBSplineCurve;