File indexing completed on 2024-05-19 16:37:06

 /*
     SPDX-FileCopyrightText: 2006-2009 John Tapsell <tapsell@kde.org>
 
     SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
 */
 
 #ifndef KGRAPHICSSIGNALPLOTTER_H
 #define KGRAPHICSSIGNALPLOTTER_H
 
 #include <QColor>
 #include <QFont>
 #include <QGraphicsWidget>
 #include <QList>
 #include <QString>
 #include <klocalizedstring.h>
 
 class QGraphicsSceneResizeEvent;
 class KGraphicsSignalPlotterPrivate;
 
 // Make sure only declare KLocalizedString once
 #ifndef KSIGNALPLOTTER_H
 Q_DECLARE_METATYPE(KLocalizedString)
 #endif
 
 /** \class KGraphicsSignalPlotter
  * \brief The KGraphicsSignalPlotter graphics widget draws a real time graph of data that updates continually.
  *
  *  Features include:
  *  \li Points are joined by a bezier curve.
  *  \li Lines are anti-aliased
  *  \li Background can be set as a specified SVG
  *  \li The lines can be reordered
  *  \li Uses as little memory and CPU as possible
  *  \li Graph can be smoothed using the formula (value * 2 + last_value)/3
  *  \li Can cope with positive/negative infinity and NaN values.
  *
  *  Example usage:
  *  \code
  *    KGraphicsSignalPlotter *s = KGraphicsSignalPlotter(parent);
  *    s->addBeam(Qt::blue);
  *    s->addBeam(Qt::green);
  *    QList<qreal> data;
  *    data << 4.0 << 5.0;
  *    s->addSample(data);
  *  \endcode
  *
  *  Note that the number of horizontal lines is calculated automatically based on the axis font size, even if the axis labels are not shown.
  *
  *  Smoothing looks very nice visually and is enabled by default.  It can be disabled with setSmoothGraph().
  *
  *  \image KSignalPlotter.png  Example KGraphicsSignalPlotter with two beams
  */
 class Q_DECL_EXPORT KGraphicsSignalPlotter : public QGraphicsWidget
 {
     Q_OBJECT
     Q_PROPERTY(qreal minimumValue READ minimumValue WRITE setMinimumValue)
     Q_PROPERTY(qreal maximumValue READ maximumValue WRITE setMaximumValue)
     Q_PROPERTY(bool useAutoRange READ useAutoRange WRITE setUseAutoRange)
     Q_PROPERTY(KLocalizedString unit READ unit WRITE setUnit)
     Q_PROPERTY(qreal scaleDownBy READ scaleDownBy WRITE setScaleDownBy)
     Q_PROPERTY(uint horizontalScale READ horizontalScale WRITE setHorizontalScale)
     Q_PROPERTY(bool showHorizontalLines READ showHorizontalLines WRITE setShowHorizontalLines)
     Q_PROPERTY(bool showVerticalLines READ showVerticalLines WRITE setShowVerticalLines)
     Q_PROPERTY(bool verticalLinesScroll READ verticalLinesScroll WRITE setVerticalLinesScroll)
     Q_PROPERTY(uint verticalLinesDistance READ verticalLinesDistance WRITE setVerticalLinesDistance)
     Q_PROPERTY(bool showAxis READ showAxis WRITE setShowAxis)
     Q_PROPERTY(QString svgBackground READ svgBackground WRITE setSvgBackground)
     Q_PROPERTY(bool thinFrame READ thinFrame WRITE setThinFrame)
     Q_PROPERTY(int maxAxisTextWidth READ maxAxisTextWidth WRITE setMaxAxisTextWidth)
     Q_PROPERTY(bool smoothGraph READ smoothGraph WRITE setSmoothGraph)
     Q_PROPERTY(bool stackGraph READ stackGraph WRITE setStackGraph)
     Q_PROPERTY(int fillOpacity READ fillOpacity WRITE setFillOpacity)
 
 public:
     KGraphicsSignalPlotter(QGraphicsItem *parent = nullptr);
     ~KGraphicsSignalPlotter() override;
 
     /** \brief Add a new line to the graph plotter, with the specified color.
      *
      *  Note that the order you add the beams in must be the same order that
      *  the beam data is given in (Unless you reorder the beams).
      *
      *  \param color Color of beam - does not have to be unique.
      */
     void addBeam(const QColor &color);
 
     /** \brief Add data to the graph, and advance the graph by one time period.
      *
      *  The data must be given as a list in the same order that the beams were
      *  added (or consequently reordered).  If samples.count() != numBeams(),
      *  a warning is printed and the data discarded.
      *
      *  To indicate that no data is available for a given beam, set its value to
      *  (non-signalling) NaN.
      *
      *  For example:
      *
      *  \code
      *    KSignalPlotter *s = KSignalPlotter(parent);
      *    s->addBeam(Qt::red);
      *    s->addBeam(Qt::green);
      *    s->addBeam(Qt::blue);
      *    signalPlotter->addSample( QList<qreal>() << std::numeric_limits<qreal>::quiet_NaN() << 1.0/0 << 10.0 );
      *  \endcode
      *
      *  This indicates that no data is available yet for red (so the beam will not be drawn for this section),
      *  that's it positive infinity for green, and 10 for blue.
      *
      *  Infinity is handled by drawing a straight line up to the top or bottom of the display, and does not affect the range.
      *  For the above example, the displayed range would now be 0 to 10.
      */
     void addSample(const QList<qreal> &samples);
 
     /** \brief Reorder the beams into the order given.
      *
      * For example:
      * \code
      *   KSignalPlotter *s = KSignalPlotter(parent);
      *   s->addBeam(Qt::blue);
      *   s->addBeam(Qt::green);
      *   s->addBeam(Qt::red);
      *   QList<int> neworder;
      *   neworder << 2 << 0 << 1;
      *   s->reorderBeams( newOrder);
      *   //Now the order is red, blue then green
      * \endcode
      *
      * The size of the \p newOrder list must be equal to the result of numBeams().
      * \param newOrder New order of beams.
      */
     void reorderBeams(const QList<int> &newOrder);
 
     /** \brief Removes the beam at the specified index.
      *
      * This causes the graph to be redrawn with the specified beam completely
      * removed.
      */
     void removeBeam(int index);
 
     /** \brief Get the color of the beam at the specified index.
      *
      * For example:
      * \code
      *   KSignalPlotter *s = KSignalPlotter(parent);
      *   s->addBeam(Qt::blue);
      *   s->addBeam(Qt::green);
      *   s->addBeam(Qt::red);
      *
      *   QColor color = s->beamColor(0);  //returns blue
      * \endcode
      *
      * \sa setBeamColor()
      */
     QColor beamColor(int index) const;
 
     /** \brief Set the color of the beam at the specified index.
      *
      * \sa beamColor()
      */
     void setBeamColor(int index, const QColor &color);
 
     /** \brief Returns the number of beams. */
     int numBeams() const;
 
     /** \brief Set the axis units with a localized string.
      *
      * The localized string must contain a placeholder "%1" which is substituted for the value.
      * The plural form (ki18np) can be used if the unit string changes depending on the number (for example
      * "1 second", "2 seconds").
      *
      * For example:
      *
      * \code
      *   KSignalPlotter plotter;
      *   plotter.setUnit( ki18ncp("Units", "%1 second", "%1 seconds") );
      *   QString formattedString = plotter.valueAsString(3.4); //returns "3.4 seconds"
      * \endcode
      *
      * Typically a new unit would be set when setScaleDownBy is called.
      * Note that even the singular should use "%1 second" instead of "1 second", so that a value of -1 works correctly.
      *
      * \see unit(), setScaleDownBy()
      */
     void setUnit(const KLocalizedString &unit);
 
     /** \brief The localizable units used on the vertical axis of the graph.
      *
      * The returns the localizable string set with setUnit().
      *
      * Default is the string "%1" - i.e. to just display the number.
      *
      * \see setUnit
      */
     KLocalizedString unit() const;
 
     /** \brief Scale all the values down by the given amount.
      *
      * This is useful when the data is given in, say, kilobytes, but you set
      * the units as megabytes.  Thus you would have to call this with @p value
      * set to 1024.  This affects all the data already entered.
      *
      * Typically this is followed by calling setUnit() to set the display axis
      * units.  Default value is 1.
      */
     void setScaleDownBy(qreal value);
 
     /** \brief Amount scaled down by.
      *
      * \sa setScaleDownBy */
     qreal scaleDownBy() const;
 
     /** \brief Set whether to scale the graph automatically beyond the given range.
      *
      * If true, the range on vertical axis is automatically expanded from the
      * data available, expanding beyond the range set by changeRange() if data
      * values are outside of this range.
      *
      * Regardless whether this is set of not, the range of the vertical axis
      * will never be less than the range given by maximumValue() and minimumvalue().
      *
      * \param value Whether to scale beyond the given range. Default is true.
      *
      * \sa useAutoRange
      */
     void setUseAutoRange(bool value);
 
     /** \brief Whether the vertical axis range is set automatically.
      */
     bool useAutoRange() const;
 
     /** \brief Change the minimum and maximum values drawn on the graph.
      *
      *  Note that these values are sanitised.  For example, if you
      *  set the minimum as 3, and the maximum as 97, then the graph
      *  would be drawn between 0 and 100.  The algorithm to determine
      *  this "nice range" attempts to minimize the number of non-zero
      *  digits.
      *
      *  If autoRange() is true, then this range is taking as a 'hint'.
      *  The range will never be smaller than the given range, but can grow
      *  if there are values larger than the given range.
      *
      *  This is equivalent to calling
      *  \code
      *    setMinimumValue(min);
      *    setMaximumValue(max);
      *  \endcode
      *
      *  \sa setMinimumValue(), setMaximumValue(), minimumValue(), maximumValue()
      */
     void changeRange(qreal min, qreal max);
 
     /** \brief Set the min value hint for the vertical axis.
      *
      * \sa changeRange(), minimumValue(), setMaximumValue(), maximumValue() */
     void setMinimumValue(qreal min);
 
     /** \brief Get the min value hint for the vertical axis.
      *
      * \sa changeRange(), minimumValue(), setMaximumValue(), maximumValue() */
     qreal minimumValue() const;
 
     /** \brief Set the max value hint for the vertical axis. *
      *
      * \sa changeRange(), minimumValue(), setMaximumValue(), maximumValue() */
     void setMaximumValue(qreal max);
 
     /** \brief Get the maximum value hint for the vertical axis.
      *
      * \sa changeRange(), minimumValue(), setMaximumValue(), maximumValue() */
     qreal maximumValue() const;
 
     /** \brief Get the current maximum value on the y-axis.
      *
      *  This will never be lower than maximumValue(), and if autoRange() is true,
      *  it will be equal or larger (due to rounding up to make it a nice number)
      *  than the highest value being shown.
      */
     qreal currentMaximumRangeValue() const;
     /** \brief Get the current minimum value on the y-axis.
      *
      *  This will never be lower than minimumValue(), and if autoRange() is true,
      *  it will be equal or larger (due to rounding up to make it a nice number)
      *  than the highest value being shown.
      */
     qreal currentMinimumRangeValue() const;
 
     /** \brief Set the number of pixels horizontally between data points.
      *  Default is 6. */
     void setHorizontalScale(uint scale);
     /** \brief The number of pixels horizontally between data points.
      *  Default is 6. */
     int horizontalScale() const;
 
     /** \brief Set whether to draw the vertical grid lines.
      *  Default is false. */
     void setShowVerticalLines(bool value);
     /** \brief Whether to draw the vertical grid lines.
      *  Default is false. */
     bool showVerticalLines() const;
 
     /** \brief Set the horizontal distance, in pixels, between the vertical grid lines.
      *  Must be a distance of 1 or more.
      *  Default is 30 pixels. */
     void setVerticalLinesDistance(uint distance);
     /** \brief The horizontal distance, in pixels, between the vertical grid lines.
      *  Default is 30 pixels. */
     uint verticalLinesDistance() const;
 
     /** \brief Set whether the vertical lines move with the data.
      *  Default is true. This has no effect is showVerticalLines is false. */
     void setVerticalLinesScroll(bool value);
     /** \brief Whether the vertical lines move with the data.
      *  Default is true. This has no effect is showVerticalLines is false. */
     bool verticalLinesScroll() const;
 
     /** \brief Set whether to draw the horizontal grid lines.
      *  Default is true. */
     void setShowHorizontalLines(bool value);
     /** \brief Whether to draw the horizontal grid lines.
      *  Default is true. */
     bool showHorizontalLines() const;
 
     /** \brief The number of decimal places used for the axis labels
      *
      *  This is calculated based on the current range */
     int currentAxisPrecision() const;
 
     /** \brief Set whether to show the vertical axis labels.
      *
      * Default is true.
      * \sa showAxis(), setAxisFont(), setAxisFontColor(), setMaxAxisTextWidth() */
     void setShowAxis(bool show);
     /** \brief Whether to show the vertical axis labels.
      *
      * Default is true.
      * \sa setShowAxis(), axisFont(), axisFontColor(), maxAxisTextWidth() */
     bool showAxis() const;
 
     /** \brief Set the filename of the SVG background.
      *
      * Set to empty (default) to disable again. */
     void setSvgBackground(const QString &filename);
 
     /** \brief The filename of the SVG background. */
     QString svgBackground() const;
 
     /** \brief Return the last value that we have for the given beam index.
      *
      * \return last value, or 0 if not known. */
     qreal lastValue(int index) const;
 
     /** \brief Return a translated string for the last value at the given index.
      *
      * Returns, for example,  "34 %" or "100 KB" for the given beam index,
      * using the last value set for the beam, using the given precision.
      *
      * If precision is -1 (the default) then if @p value is greater than 99.5, no decimal figures are shown,
      * otherwise if @p value is greater than 0.995, 1 decimal figure is used, otherwise 2.
      */
     QString lastValueAsString(int index, int precision = -1) const;
 
     /** \brief Return a translated string for the given value.
      *
      * Returns, for example, "34 %" or "100 KB" for the given value in unscaled units.
      *
      * If precision is -1 (the default) then if @p value is greater than 99.5, no decimal figures are shown,
      * otherwise if @p value is greater than 0.995, 1 decimal figure is used, otherwise 2.
      *
      * For example:
      * \code
      *   KSignalPlotter plotter;
      *   plotter.setUnit( ki18ncp("Units", "1 hour", "%1 hours") );
      *   plotter.scaleDownBy( 60 ); //The input will be in seconds, and there's 60 seconds in an hour
      *   QString formattedString = plotter.valueAsString(150); //returns "2.5 hours"
      * \endcode
      *
      */
     QString valueAsString(qreal value, int precision = -1) const;
 
     /** \brief Set the distance between the left of the widget and the left of the plotting region.
      *
      *  For example:
      *  \code
      *      int axisTextWidth = fontMetrics().width(i18nc("Largest axis title", "99999 XXXX"));
      *      plotter->setMaxAxisTextWidth(axisTextWidth);
      *  \endcode
      *
      *  If this is 0, the default, then the text will be shown inside the plotting area.
      */
     void setMaxAxisTextWidth(int maxAxisTextWidth);
     /** \brief Get the distance between the left of the widget and the left of the plotting region. */
     int maxAxisTextWidth() const;
 
     /** \brief Set whether to smooth the graph by averaging the points.
      *
      * This uses the formula:  (value*2 + last_value)/3.
      * Default is true. */
     void setSmoothGraph(bool smooth);
     /** \brief Whether to smooth the graph by averaging the points.
      *
      * This uses the formula:  (value*2 + last_value)/3.
      * Default is true. */
     bool smoothGraph() const;
 
     /** \brief Set whether to stack the beams on top of each other.
      *
      * Default is false */
     void setStackGraph(bool stack);
     /** \brief Whether to stack the beams on top of each other.
      *
      * Default is false */
     bool stackGraph() const;
 
     /** \brief Alpha value for filling the area underneath the graph lines.
      *
      * Set to 0 to disable filling the graph, and 255 for a solid fill. Default is 20*/
     void setFillOpacity(int fill);
     /** \brief Alpha value for filling the area underneath the graph lines. */
     int fillOpacity() const;
 
     /* Whether to show a thin line on the left and bottom of the widget, for a slight 3D effect */
     bool thinFrame() const;
     /* Set whether to show a thin line on the left and bottom of the widget, for a slight 3D effect */
     void setThinFrame(bool thinFrame);
 
 Q_SIGNALS:
     /** When the axis has changed this signal is emitted. */
     void axisScaleChanged();
 
 protected:
     /* Reimplemented */
     void resizeEvent(QGraphicsSceneResizeEvent *event) override;
     void paint(QPainter *p, const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr) override;
     QSizeF sizeHint(Qt::SizeHint which, const QSizeF &constraint = QSizeF()) const override;
     void changeEvent(QEvent *event) override;
     QPainterPath opaqueArea() const override;
 
 private:
     KGraphicsSignalPlotterPrivate *const d;
     friend class KGraphicsSignalPlotterPrivate;
 };
 
 #endif