text: /****************************************************************************
  **
  ** Copyright (C) 2016 The Qt Company Ltd.
  ** Contact: https://www.qt.io/licensing/
  **
  ** This file is part of the Qt Charts module of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:GPL$
  ** Commercial License Usage
  ** Licensees holding valid commercial Qt licenses may use this file in
  ** accordance with the commercial license agreement provided with the
  ** Software or, alternatively, in accordance with the terms contained in
  ** a written agreement between you and The Qt Company. For licensing terms
  ** and conditions see https://www.qt.io/terms-conditions. For further
  ** information use the contact form at https://www.qt.io/contact-us.
  **
  ** GNU General Public License Usage
  ** Alternatively, this file may be used under the terms of the GNU
  ** General Public License version 3 or (at your option) any later version
  ** approved by the KDE Free Qt Foundation. The licenses are as published by
  ** the Free Software Foundation and appearing in the file LICENSE.GPL3
  ** included in the packaging of this file. Please review the following
  ** information to ensure the GNU General Public License requirements will
  ** be met: https://www.gnu.org/licenses/gpl-3.0.html.
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/
  
  //  W A R N I N G
  //  -------------
  //
  // This file is not part of the Qt Chart API.  It exists purely as an
  // implementation detail.  This header file may change from version to
  // version without notice, or even be removed.
  //
  // We mean it.
  
  #ifndef SPLINECHARTITEM_P_H
  #define SPLINECHARTITEM_P_H
  
  #include <QtCharts/QSplineSeries>
  #include <private/xychart_p.h>
  
  QT_CHARTS_BEGIN_NAMESPACE
  
  class SplineAnimation;
  
  class SplineChartItem : public XYChart
  {
      Q_OBJECT
      Q_INTERFACES(QGraphicsItem)
  public:
      SplineChartItem(QSplineSeries *series, QGraphicsItem *item = 0);
  
      //from QGraphicsItem
      QRectF boundingRect() const;
      void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget);
      QPainterPath shape() const;
  
      void setControlGeometryPoints(QVector<QPointF>& points);
      QVector<QPointF> controlGeometryPoints() const;
  
      void setAnimation(SplineAnimation *animation);
      ChartAnimation *animation() const;
  
  public Q_SLOTS:
      void handleUpdated();
  
  protected:
      void updateGeometry();
      QVector<QPointF> calculateControlPoints(const QVector<QPointF> &points);
      QVector<qreal> firstControlPoints(const QVector<qreal>& vector);
      void updateChart(QVector<QPointF> &oldPoints, QVector<QPointF> &newPoints, int index);
      void mousePressEvent(QGraphicsSceneMouseEvent *event);
      void hoverEnterEvent(QGraphicsSceneHoverEvent *event);
      void hoverLeaveEvent(QGraphicsSceneHoverEvent *event);
      void mouseReleaseEvent(QGraphicsSceneMouseEvent *event);
      void mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event);
  
  private:
      QSplineSeries *m_series;
      QPainterPath m_path;
      QPainterPath m_pathPolarRight;
      QPainterPath m_pathPolarLeft;
      QPainterPath m_fullPath;
      QRectF m_rect;
      QPen m_linePen;
      QPen m_pointPen;
      bool m_pointsVisible;
      QVector<QPointF> m_controlPoints;
      QVector<QPointF> m_visiblePoints;
      SplineAnimation *m_animation;
  
      bool m_pointLabelsVisible;
      QString m_pointLabelsFormat;
      QFont m_pointLabelsFont;
      QColor m_pointLabelsColor;
      bool m_pointLabelsClipping;
  
      QPointF m_lastMousePos;
      bool m_mousePressed;
  
      friend class SplineAnimation;
  };
  
  QT_CHARTS_END_NAMESPACE
  
  #endif // SPLINECHARTITEM_P_H
  