qsplineseries.cpp
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r794 | /**************************************************************************** | ||
** | ||||
** Copyright (C) 2012 Digia Plc | ||||
** All rights reserved. | ||||
** For any questions to Digia, please use contact form at http://qt.digia.com | ||||
** | ||||
** This file is part of the Qt Commercial Charts Add-on. | ||||
** | ||||
** $QT_BEGIN_LICENSE$ | ||||
** Licensees holding valid Qt Commercial licenses may use this file in | ||||
** accordance with the Qt Commercial License Agreement provided with the | ||||
** Software or, alternatively, in accordance with the terms contained in | ||||
** a written agreement between you and Digia. | ||||
** | ||||
** If you have questions regarding the use of this file, please use | ||||
** contact form at http://qt.digia.com | ||||
** $QT_END_LICENSE$ | ||||
** | ||||
****************************************************************************/ | ||||
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r295 | #include "qsplineseries.h" | ||
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r938 | #include "qsplineseries_p.h" | ||
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r943 | #include "splinechartitem_p.h" | ||
#include "chartdataset_p.h" | ||||
#include "charttheme_p.h" | ||||
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r1735 | #include "splineanimation_p.h" | ||
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r295 | |||
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r433 | /*! | ||
\class QSplineSeries | ||||
\brief Series type used to store data needed to draw a spline. | ||||
QSplineSeries stores the data points along with the segment control points needed by QPainterPath to draw spline | ||||
Control points are automatically calculated when data changes. The algorithm computes the points so that the normal spline can be drawn. | ||||
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r995 | |||
\image examples_splinechart.png | ||||
Creating basic spline chart is simple: | ||||
\code | ||||
QSplineSeries* series = new QSplineSeries(); | ||||
series->append(0, 6); | ||||
series->append(2, 4); | ||||
... | ||||
chart->addSeries(series); | ||||
\endcode | ||||
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r433 | */ | ||
/*! | ||||
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r1491 | \qmlclass SplineSeries QSplineSeries | ||
\inherits XYSeries | ||||
The following QML shows how to create a simple spline chart: | ||||
\snippet ../demos/qmlchart/qml/qmlchart/View3.qml 1 | ||||
\beginfloatleft | ||||
\image demos_qmlchart3.png | ||||
\endfloat | ||||
\clearfloat | ||||
*/ | ||||
/*! | ||||
\fn QSeriesType QSplineSeries::type() const | ||||
Returns the type of the series | ||||
*/ | ||||
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r433 | |||
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r1904 | /*! | ||
\qmlproperty AbstractAxis SplineSeries::axisX | ||||
The x axis used for the series. If you leave the x axis undefined, a ValueAxis is created for | ||||
the series. | ||||
*/ | ||||
/*! | ||||
\qmlproperty AbstractAxis SplineSeries::axisY | ||||
The y axis used for the series. If you leave the y axis undefined, a ValueAxis is created for | ||||
the series. | ||||
*/ | ||||
/*! | ||||
\qmlproperty real SplineSeries::width | ||||
The width of the line. By default the width is 2.0. | ||||
*/ | ||||
/*! | ||||
\qmlproperty Qt::PenStyle SplineSeries::style | ||||
Controls the style of the line. Set to one of Qt.NoPen, Qt.SolidLine, Qt.DashLine, Qt.DotLine, | ||||
Qt.DashDotLine or Qt.DashDotDotLine. Using Qt.CustomDashLine is not supported in the QML API. | ||||
By default the style is Qt.SolidLine. | ||||
*/ | ||||
/*! | ||||
\qmlproperty Qt::PenCapStyle SplineSeries::capStyle | ||||
Controls the cap style of the line. Set to one of Qt.FlatCap, Qt.SquareCap or Qt.RoundCap. By | ||||
default the cap style is Qt.SquareCap. | ||||
*/ | ||||
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r401 | QTCOMMERCIALCHART_BEGIN_NAMESPACE | ||
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r433 | /*! | ||
Constructs empty series object which is a child of \a parent. | ||||
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r974 | When series object is added to QChartView or QChart instance then the ownerships is transferred. | ||
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r433 | */ | ||
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r2097 | QSplineSeries::QSplineSeries(QObject *parent) | ||
: QLineSeries(*new QSplineSeriesPrivate(this), parent) | ||||
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r295 | { | ||
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r1275 | Q_D(QSplineSeries); | ||
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r2097 | QObject::connect(this, SIGNAL(pointAdded(int)), d, SLOT(updateControlPoints())); | ||
QObject::connect(this, SIGNAL(pointRemoved(int)), d, SLOT(updateControlPoints())); | ||||
QObject::connect(this, SIGNAL(pointReplaced(int)), d, SLOT(updateControlPoints())); | ||||
QObject::connect(this, SIGNAL(pointsReplaced()), d, SLOT(updateControlPoints())); | ||||
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r295 | } | ||
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r305 | |||
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r1351 | /*! | ||
Destroys the object. | ||||
*/ | ||||
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r1082 | QSplineSeries::~QSplineSeries() | ||
{ | ||||
Q_D(QSplineSeries); | ||||
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r2097 | if (d->m_dataset) | ||
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r1160 | d->m_dataset->removeSeries(this); | ||
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r1082 | } | ||
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r1107 | QAbstractSeries::SeriesType QSplineSeries::type() const | ||
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r938 | { | ||
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r988 | return QAbstractSeries::SeriesTypeSpline; | ||
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r938 | } | ||
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// | ||||
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r2104 | QSplineSeriesPrivate::QSplineSeriesPrivate(QSplineSeries *q) | ||
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r2097 | : QLineSeriesPrivate(q) | ||
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r938 | { | ||
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r1309 | } | ||
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r938 | |||
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r433 | /*! | ||
Calculates control points which are needed by QPainterPath.cubicTo function to draw the cubic Bezier cureve between two points. | ||||
*/ | ||||
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r938 | void QSplineSeriesPrivate::calculateControlPoints() | ||
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r401 | { | ||
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r1059 | Q_Q(QSplineSeries); | ||
const QList<QPointF>& points = q->points(); | ||||
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r401 | |||
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r1059 | int n = points.count() - 1; | ||
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r1049 | |||
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r2097 | if (n == 1) { | ||
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r1049 | //for n==1 | ||
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r1059 | m_controlPoints[0].setX((2 * points[0].x() + points[1].x()) / 3); | ||
m_controlPoints[0].setY((2 * points[0].y() + points[1].y()) / 3); | ||||
m_controlPoints[1].setX(2 * m_controlPoints[0].x() - points[0].x()); | ||||
m_controlPoints[1].setY(2 * m_controlPoints[0].y() - points[0].y()); | ||||
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r401 | return; | ||
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r318 | } | ||
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r401 | // Calculate first Bezier control points | ||
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r1363 | // Set of equations for P0 to Pn points. | ||
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r401 | // | ||
// | 2 1 0 0 ... 0 0 0 ... 0 0 0 | | P1_1 | | P0 + 2 * P1 | | ||||
// | 1 4 1 0 ... 0 0 0 ... 0 0 0 | | P1_2 | | 4 * P1 + 2 * P2 | | ||||
// | 0 1 4 1 ... 0 0 0 ... 0 0 0 | | P1_3 | | 4 * P2 + 2 * P3 | | ||||
// | . . . . . . . . . . . . | | ... | | ... | | ||||
// | 0 0 0 0 ... 1 4 1 ... 0 0 0 | * | P1_i | = | 4 * P(i-1) + 2 * Pi | | ||||
// | . . . . . . . . . . . . | | ... | | ... | | ||||
// | 0 0 0 0 0 0 0 0 ... 1 4 1 | | P1_(n-1)| | 4 * P(n-2) + 2 * P(n-1) | | ||||
// | 0 0 0 0 0 0 0 0 ... 0 2 7 | | P1_n | | 8 * P(n-1) + Pn | | ||||
// | ||||
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r1057 | QVector<qreal> vector; | ||
vector.resize(n); | ||||
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r401 | |||
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r1059 | vector[0] = points[0].x() + 2 * points[1].x(); | ||
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r401 | |||
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r2097 | for (int i = 1; i < n - 1; ++i) | ||
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r1059 | vector[i] = 4 * points[i].x() + 2 * points[i + 1].x(); | ||
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r1049 | |||
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r2097 | vector[n - 1] = (8 * points[n - 1].x() + points[n].x()) / 2.0; | ||
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r1049 | |||
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r1057 | QVector<qreal> xControl = firstControlPoints(vector); | ||
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r1059 | vector[0] = points[0].y() + 2 * points[1].y(); | ||
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r1049 | |||
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r2097 | for (int i = 1; i < n - 1; ++i) | ||
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r1059 | vector[i] = 4 * points[i].y() + 2 * points[i + 1].y(); | ||
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r1049 | |||
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r2097 | vector[n - 1] = (8 * points[n - 1].y() + points[n].y()) / 2.0; | ||
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r1057 | |||
QVector<qreal> yControl = firstControlPoints(vector); | ||||
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r401 | |||
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r2097 | for (int i = 0, j = 0; i < n; ++i, ++j) { | ||
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r401 | |||
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r1057 | m_controlPoints[j].setX(xControl[i]); | ||
m_controlPoints[j].setY(yControl[i]); | ||||
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r1049 | |||
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r1057 | j++; | ||
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r1049 | |||
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r2097 | if (i < n - 1) { | ||
m_controlPoints[j].setX(2 * points[i + 1].x() - xControl[i + 1]); | ||||
m_controlPoints[j].setY(2 * points[i + 1].y() - yControl[i + 1]); | ||||
} else { | ||||
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r1059 | m_controlPoints[j].setX((points[n].x() + xControl[n - 1]) / 2); | ||
m_controlPoints[j].setY((points[n].y() + yControl[n - 1]) / 2); | ||||
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r1057 | } | ||
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r318 | } | ||
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r401 | } | ||
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r1057 | QVector<qreal> QSplineSeriesPrivate::firstControlPoints(const QVector<qreal>& vector) | ||
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r401 | { | ||
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r1057 | QVector<qreal> result; | ||
int count = vector.count(); | ||||
result.resize(count); | ||||
result[0] = vector[0] / 2.0; | ||||
QVector<qreal> temp; | ||||
temp.resize(count); | ||||
temp[0] = 0; | ||||
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r401 | |||
qreal b = 2.0; | ||||
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r1057 | |||
for (int i = 1; i < count; i++) { | ||||
temp[i] = 1 / b; | ||||
b = (i < count - 1 ? 4.0 : 3.5) - temp[i]; | ||||
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r2097 | result[i] = (vector[i] - result[i - 1]) / b; | ||
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r401 | } | ||
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r2097 | |||
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r1057 | for (int i = 1; i < count; i++) | ||
result[count - i - 1] -= temp[count - i] * result[count - i]; | ||||
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r401 | |||
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r1049 | return result; | ||
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r401 | } | ||
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r431 | |||
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r1160 | QPointF QSplineSeriesPrivate::controlPoint(int index) const | ||
{ | ||||
return m_controlPoints[index]; | ||||
} | ||||
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r433 | /*! | ||
Updates the control points, besed on currently avaiable knots. | ||||
*/ | ||||
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r938 | void QSplineSeriesPrivate::updateControlPoints() | ||
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r431 | { | ||
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r1059 | Q_Q(QSplineSeries); | ||
if (q->count() > 1) { | ||||
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r2097 | m_controlPoints.resize(2 * q->count() - 2); | ||
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r431 | calculateControlPoints(); | ||
} | ||||
} | ||||
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r2104 | ChartElement *QSplineSeriesPrivate::createGraphics(ChartPresenter *presenter) | ||
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r943 | { | ||
Q_Q(QSplineSeries); | ||||
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r2097 | SplineChartItem *spline = new SplineChartItem(q, presenter); | ||
if (presenter->animationOptions().testFlag(QChart::SeriesAnimations)) | ||||
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r1217 | spline->setAnimation(new SplineAnimation(spline)); | ||
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r943 | presenter->chartTheme()->decorate(q, presenter->dataSet()->seriesIndex(q)); | ||
return spline; | ||||
} | ||||
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r401 | #include "moc_qsplineseries.cpp" | ||
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r938 | #include "moc_qsplineseries_p.cpp" | ||
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r401 | |||
QTCOMMERCIALCHART_END_NAMESPACE | ||||