qwt_spline_curve_fitter.cpp

/******************************************************************************
 * 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
 *****************************************************************************/
 
#include "qwt_spline_curve_fitter.h"
#include "qwt_spline_local.h"
#include "qwt_spline_parametrization.h"
 
#include <qpolygon.h>
#include <qpainterpath.h>
 
QwtSplineCurveFitter::QwtSplineCurveFitter()
    : QwtCurveFitter( QwtCurveFitter::Path )
{
    m_spline = new QwtSplineLocal( QwtSplineLocal::Cardinal );
    m_spline->setParametrization( QwtSplineParametrization::ParameterUniform );
}
 
QwtSplineCurveFitter::~QwtSplineCurveFitter()
{
    delete m_spline;
}
 
void QwtSplineCurveFitter::setSpline( QwtSpline* spline )
{
    if ( m_spline == spline )
        return;
 
    delete m_spline;
    m_spline = spline;
}
 
const QwtSpline* QwtSplineCurveFitter::spline() const
{
    return m_spline;
}
 
QwtSpline* QwtSplineCurveFitter::spline()
{
    return m_spline;
}
 
QPolygonF QwtSplineCurveFitter::fitCurve( const QPolygonF& points ) const
{
    const QPainterPath path = fitCurvePath( points );
 
    const QList< QPolygonF > subPaths = path.toSubpathPolygons();
    if ( subPaths.size() == 1 )
        return subPaths.first();
 
    return QPolygonF();
}
 
QPainterPath QwtSplineCurveFitter::fitCurvePath( const QPolygonF& points ) const
{
    QPainterPath path;
 
    if ( m_spline )
        path = m_spline->painterPath( points );
 
    return path;
}