qwt_spline.h

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/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
 * Qwt Widget Library
 * Copyright (C) 1997   Josef Wilgen
 * Copyright (C) 2002   Uwe Rathmann
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the Qwt License, Version 1.0
 *****************************************************************************/

#ifndef QWT_SPLINE_H
#define QWT_SPLINE_H 1

#include "qwt_global.h"
#include "qwt_spline.h"
#include "qwt_spline_polynomial.h"
#include <qpolygon.h>
#include <qpainterpath.h>
#include <qmath.h>

class QwtSplineParametrization;

class QWT_EXPORT QwtSpline
{
public:
    enum BoundaryType
    {
        ConditionalBoundaries,

        PeriodicPolygon,

        ClosedPolygon
    };

    enum BoundaryPosition
    {
        AtBeginning,

        AtEnd
    };

    enum BoundaryCondition
    {
        Clamped1,
        
        Clamped2,
        
        Clamped3,

        LinearRunout
    };  

    QwtSpline();
    virtual ~QwtSpline();

    void setParametrization( int type );
    void setParametrization( QwtSplineParametrization * );
    const QwtSplineParametrization *parametrization() const;

    void setBoundaryType( BoundaryType );
    BoundaryType boundaryType() const;

    void setBoundaryValue( BoundaryPosition, double value );
    double boundaryValue( BoundaryPosition ) const; 
    
    void setBoundaryCondition( BoundaryPosition, int condition );
    int boundaryCondition( BoundaryPosition ) const;

    void setBoundaryConditions( int condition,
        double valueBegin = 0.0, double valueEnd = 0.0 );

    virtual QPolygonF polygon( const QPolygonF &, double tolerance ) const;
    virtual QPainterPath painterPath( const QPolygonF & ) const = 0;

    virtual uint locality() const;

private:
    Q_DISABLE_COPY(QwtSpline)

    class PrivateData;
    PrivateData *d_data;
};

class QWT_EXPORT QwtSplineInterpolating: public QwtSpline
{
public:
    QwtSplineInterpolating();
    virtual ~QwtSplineInterpolating();

    virtual QPolygonF equidistantPolygon( const QPolygonF &, 
        double distance, bool withNodes ) const;

    virtual QPolygonF polygon( const QPolygonF &, double tolerance ) const;

    virtual QPainterPath painterPath( const QPolygonF & ) const;
    virtual QVector<QLineF> bezierControlLines( const QPolygonF &points ) const = 0;

private:
    Q_DISABLE_COPY(QwtSplineInterpolating)
};

class QWT_EXPORT QwtSplineG1: public QwtSplineInterpolating
{           
public:     
    QwtSplineG1();
    virtual ~QwtSplineG1();
};

class QWT_EXPORT QwtSplineC1: public QwtSplineG1
{
public:
    QwtSplineC1();
    virtual ~QwtSplineC1();

    virtual QPainterPath painterPath( const QPolygonF & ) const;
    virtual QVector<QLineF> bezierControlLines( const QPolygonF & ) const;

    virtual QPolygonF equidistantPolygon( const QPolygonF &,
        double distance, bool withNodes ) const;

    // these methods are the non parametric part
    virtual QVector<QwtSplinePolynomial> polynomials( const QPolygonF & ) const;
    virtual QVector<double> slopes( const QPolygonF & ) const = 0;

    virtual double slopeAtBeginning( const QPolygonF &, double slopeNext ) const;
    virtual double slopeAtEnd( const QPolygonF &, double slopeBefore ) const;
};

class QWT_EXPORT QwtSplineC2: public QwtSplineC1
{
public:
    enum BoundaryConditionC2
    {
        CubicRunout = LinearRunout + 1, 

        NotAKnot
    };

    QwtSplineC2();
    virtual ~QwtSplineC2();

    virtual QPainterPath painterPath( const QPolygonF & ) const;
    virtual QVector<QLineF> bezierControlLines( const QPolygonF & ) const;

    virtual QPolygonF equidistantPolygon( const QPolygonF &,
        double distance, bool withNodes ) const;

    // calculating the parametric equations
    virtual QVector<QwtSplinePolynomial> polynomials( const QPolygonF & ) const;
    virtual QVector<double> slopes( const QPolygonF & ) const;
    virtual QVector<double> curvatures( const QPolygonF & ) const = 0;
};

#endif