File indexing completed on 2024-04-28 05:31:46

0001 /*
0002     SPDX-FileCopyrightText: 2006-2009 John Tapsell <tapsell@kde.org>
0003 
0004     SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
0005 */
0006 
0007 #ifndef KSIGNALPLOTTER_H
0008 #define KSIGNALPLOTTER_H
0009 
0010 #include <QColor>
0011 #include <QFont>
0012 #include <QList>
0013 #include <QString>
0014 #include <QWidget>
0015 #include <klocalizedstring.h>
0016 
0017 #include "ksignalplotter_export.h"
0018 
0019 class QPaintEvent;
0020 class QResizeEvent;
0021 
0022 class KSignalPlotterPrivate;
0023 
0024 // Make sure only declare KLocalizedString once
0025 #ifndef KGRAPHICSSIGNALPLOTTER_H
0026 Q_DECLARE_METATYPE(KLocalizedString)
0027 #endif
0028 
0029 /** \class KSignalPlotter
0030  * \brief The KSignalPlotter widget draws a real time graph of data that updates continually.
0031  *
0032  *  Features include:
0033  *  \li Points are joined by a bezier curve.
0034  *  \li Lines are anti-aliased
0035  *  \li Background can be set as a specified SVG
0036  *  \li The lines can be reordered
0037  *  \li Uses as little memory and CPU as possible
0038  *  \li Graph can be smoothed using the formula (value * 2 + last_value)/3
0039  *  \li Can cope with positive/negative infinity and NaN values.
0040  *
0041  *  Example usage:
0042  *  \code
0043  *    KSignalPlotter *s = KSignalPlotter(parent);
0044  *    s->addBeam(Qt::blue);
0045  *    s->addBeam(Qt::green);
0046  *    QList<qreal> data;
0047  *    data << 4.0 << 5.0;
0048  *    s->addSample(data);
0049  *  \endcode
0050  *
0051  *  Note that the number of horizontal lines is calculated automatically based on the axis font size, even if the axis labels are not shown.
0052  *
0053  *  Smoothing looks very nice visually and is enabled by default.  It can be disabled with setSmoothGraph().
0054  *
0055  *  \image KSignalPlotter.png  Example KSignalPlotter with two beams
0056  */
0057 class KSIGNALPLOTTER_EXPORT KSignalPlotter : public QWidget
0058 {
0059     Q_OBJECT
0060     Q_PROPERTY(qreal minimumValue READ minimumValue WRITE setMinimumValue)
0061     Q_PROPERTY(qreal maximumValue READ maximumValue WRITE setMaximumValue)
0062     Q_PROPERTY(bool useAutoRange READ useAutoRange WRITE setUseAutoRange)
0063     Q_PROPERTY(KLocalizedString unit READ unit WRITE setUnit)
0064     Q_PROPERTY(qreal scaleDownBy READ scaleDownBy WRITE setScaleDownBy)
0065     Q_PROPERTY(uint horizontalScale READ horizontalScale WRITE setHorizontalScale)
0066     Q_PROPERTY(bool showHorizontalLines READ showHorizontalLines WRITE setShowHorizontalLines)
0067     Q_PROPERTY(bool showVerticalLines READ showVerticalLines WRITE setShowVerticalLines)
0068     Q_PROPERTY(bool verticalLinesScroll READ verticalLinesScroll WRITE setVerticalLinesScroll)
0069     Q_PROPERTY(uint verticalLinesDistance READ verticalLinesDistance WRITE setVerticalLinesDistance)
0070     Q_PROPERTY(bool showAxis READ showAxis WRITE setShowAxis)
0071     Q_PROPERTY(QString svgBackground READ svgBackground WRITE setSvgBackground)
0072     Q_PROPERTY(bool thinFrame READ thinFrame WRITE setThinFrame)
0073     Q_PROPERTY(int maxAxisTextWidth READ maxAxisTextWidth WRITE setMaxAxisTextWidth)
0074     Q_PROPERTY(bool smoothGraph READ smoothGraph WRITE setSmoothGraph)
0075     Q_PROPERTY(bool stackGraph READ stackGraph WRITE setStackGraph)
0076     Q_PROPERTY(int fillOpacity READ fillOpacity WRITE setFillOpacity)
0077 
0078 public:
0079     explicit KSignalPlotter(QWidget *parent = nullptr);
0080     ~KSignalPlotter() override;
0081 
0082     /** \brief Add a new line to the graph plotter, with the specified color.
0083      *
0084      *  Note that the order you add the beams in must be the same order that
0085      *  the beam data is given in (Unless you reorder the beams).
0086      *
0087      *  \param color Color of beam - does not have to be unique.
0088      */
0089     void addBeam(const QColor &color);
0090 
0091     /** \brief Add data to the graph, and advance the graph by one time period.
0092      *
0093      *  The data must be given as a list in the same order that the beams were
0094      *  added (or consequently reordered).  If samples.count() != numBeams(),
0095      *  a warning is printed and the data discarded.
0096      *
0097      *  To indicate that no data is available for a given beam, set its value to
0098      *  (non-signalling) NaN.
0099      *
0100      *  For example:
0101      *
0102      *  \code
0103      *    KSignalPlotter *s = KSignalPlotter(parent);
0104      *    s->addBeam(Qt::red);
0105      *    s->addBeam(Qt::green);
0106      *    s->addBeam(Qt::blue);
0107      *    signalPlotter->addSample( QList<qreal>() << std::numeric_limits<double>::quiet_NaN() << 1.0/0 << 10.0 );
0108      *  \endcode
0109      *
0110      *  This indicates that no data is available yet for red (so the beam will not be drawn for this section),
0111      *  that's it positive infinity for green, and 10 for blue.
0112      *
0113      *  Infinity is handled by drawing a straight line up to the top or bottom of the display, and does not affect the range.
0114      *  For the above example, the displayed range would now be 0 to 10.
0115      */
0116     void addSample(const QList<qreal> &samples);
0117 
0118     /** \brief Reorder the beams into the order given.
0119      *
0120      * For example:
0121      * \code
0122      *   KSignalPlotter *s = KSignalPlotter(parent);
0123      *   s->addBeam(Qt::blue);
0124      *   s->addBeam(Qt::green);
0125      *   s->addBeam(Qt::red);
0126      *   QList<int> neworder;
0127      *   neworder << 2 << 0 << 1;
0128      *   s->reorderBeams( newOrder);
0129      *   //Now the order is red, blue then green
0130      * \endcode
0131      *
0132      * The size of the \p newOrder list must be equal to the result of numBeams().
0133      * \param newOrder New order of beams.
0134      */
0135     void reorderBeams(const QList<int> &newOrder);
0136 
0137     /** \brief Removes the beam at the specified index.
0138      *
0139      * This causes the graph to be redrawn with the specified beam completely
0140      * removed.
0141      */
0142     void removeBeam(int index);
0143 
0144     /** \brief Get the color of the beam at the specified index.
0145      *
0146      * For example:
0147      * \code
0148      *   KSignalPlotter *s = KSignalPlotter(parent);
0149      *   s->addBeam(Qt::blue);
0150      *   s->addBeam(Qt::green);
0151      *   s->addBeam(Qt::red);
0152      *
0153      *   QColor color = s->beamColor(0);  //returns blue
0154      * \endcode
0155      *
0156      * \sa setBeamColor()
0157      */
0158     QColor beamColor(int index) const;
0159 
0160     /** \brief Set the color of the beam at the specified index.
0161      *
0162      * \sa beamColor()
0163      */
0164     void setBeamColor(int index, const QColor &color);
0165 
0166     /** \brief Returns the number of beams. */
0167     int numBeams() const;
0168 
0169     /** \brief Set the axis units with a localized string.
0170      *
0171      * The localized string must contain a placeholder "%1" which is substituted for the value.
0172      * The plural form (ki18np) can be used if the unit string changes depending on the number (for example
0173      * "1 second", "2 seconds").
0174      *
0175      * For example:
0176      *
0177      * \code
0178      *   KSignalPlotter plotter;
0179      *   plotter.setUnit( ki18ncp("Units", "%1 second", "%1 seconds") );
0180      *   QString formattedString = plotter.valueAsString(3.4); //returns "3.4 seconds"
0181      * \endcode
0182      *
0183      * Typically a new unit would be set when setScaleDownBy is called.
0184      * Note that even the singular should use "%1 second" instead of "1 second", so that a value of -1 works correctly.
0185      *
0186      * \see unit(), setScaleDownBy()
0187      */
0188     void setUnit(const KLocalizedString &unit);
0189 
0190     /** \brief The localizable units used on the vertical axis of the graph.
0191      *
0192      * The returns the localizable string set with setUnit().
0193      *
0194      * Default is the string "%1" - i.e. to just display the number.
0195      *
0196      * \see setUnit
0197      */
0198     KLocalizedString unit() const;
0199 
0200     /** \brief Scale all the values down by the given amount.
0201      *
0202      * This is useful when the data is given in, say, kilobytes, but you set
0203      * the units as megabytes.  Thus you would have to call this with @p value
0204      * set to 1024.  This affects all the data already entered.
0205      *
0206      * Typically this is followed by calling setUnit() to set the display axis
0207      * units.  Default value is 1.
0208      */
0209     void setScaleDownBy(qreal value);
0210 
0211     /** \brief Amount scaled down by.
0212      *
0213      * \sa setScaleDownBy */
0214     qreal scaleDownBy() const;
0215 
0216     /** \brief Set whether to scale the graph automatically beyond the given range.
0217      *
0218      * If true, the range on vertical axis is automatically expanded from the
0219      * data available, expanding beyond the range set by changeRange() if data
0220      * values are outside of this range.
0221      *
0222      * Regardless whether this is set of not, the range of the vertical axis
0223      * will never be less than the range given by maximumValue() and minimumvalue().
0224      *
0225      * \param value Whether to scale beyond the given range. Default is true.
0226      *
0227      * \sa useAutoRange
0228      */
0229     void setUseAutoRange(bool value);
0230 
0231     /** \brief Whether the vertical axis range is set automatically.
0232      */
0233     bool useAutoRange() const;
0234 
0235     /** \brief Change the minimum and maximum values drawn on the graph.
0236      *
0237      *  Note that these values are sanitised.  For example, if you
0238      *  set the minimum as 3, and the maximum as 97, then the graph
0239      *  would be drawn between 0 and 100.  The algorithm to determine
0240      *  this "nice range" attempts to minimize the number of non-zero
0241      *  digits.
0242      *
0243      *  If autoRange() is true, then this range is taking as a 'hint'.
0244      *  The range will never be smaller than the given range, but can grow
0245      *  if there are values larger than the given range.
0246      *
0247      *  This is equivalent to calling
0248      *  \code
0249      *    setMinimumValue(min);
0250      *    setMaximumValue(max);
0251      *  \endcode
0252      *
0253      *  \sa setMinimumValue(), setMaximumValue(), minimumValue(), maximumValue()
0254      */
0255     void changeRange(qreal min, qreal max);
0256 
0257     /** \brief Set the min value hint for the vertical axis.
0258      *
0259      * \sa changeRange(), minimumValue(), setMaximumValue(), maximumValue() */
0260     void setMinimumValue(qreal min);
0261 
0262     /** \brief Get the min value hint for the vertical axis.
0263      *
0264      * \sa changeRange(), minimumValue(), setMaximumValue(), maximumValue() */
0265     qreal minimumValue() const;
0266 
0267     /** \brief Set the max value hint for the vertical axis. *
0268      *
0269      * \sa changeRange(), minimumValue(), setMaximumValue(), maximumValue() */
0270     void setMaximumValue(qreal max);
0271 
0272     /** \brief Get the maximum value hint for the vertical axis.
0273      *
0274      * \sa changeRange(), minimumValue(), setMaximumValue(), maximumValue() */
0275     qreal maximumValue() const;
0276 
0277     /** \brief Get the current maximum value on the y-axis.
0278      *
0279      *  This will never be lower than maximumValue(), and if autoRange() is true,
0280      *  it will be equal or larger (due to rounding up to make it a nice number)
0281      *  than the highest value being shown.
0282      */
0283     qreal currentMaximumRangeValue() const;
0284     /** \brief Get the current minimum value on the y-axis.
0285      *
0286      *  This will never be lower than minimumValue(), and if autoRange() is true,
0287      *  it will be equal or larger (due to rounding up to make it a nice number)
0288      *  than the highest value being shown.
0289      */
0290     qreal currentMinimumRangeValue() const;
0291 
0292     /** \brief Set the number of pixels horizontally between data points.
0293      *  Default is 6. */
0294     void setHorizontalScale(uint scale);
0295     /** \brief The number of pixels horizontally between data points.
0296      *  Default is 6. */
0297     int horizontalScale() const;
0298 
0299     /** \brief Set whether to draw the vertical grid lines.
0300      *  Default is false. */
0301     void setShowVerticalLines(bool value);
0302     /** \brief Whether to draw the vertical grid lines.
0303      *  Default is false. */
0304     bool showVerticalLines() const;
0305 
0306     /** \brief Set the horizontal distance, in pixels, between the vertical grid lines.
0307      *  Must be a distance of 1 or more.
0308      *  Default is 30 pixels. */
0309     void setVerticalLinesDistance(uint distance);
0310     /** \brief The horizontal distance, in pixels, between the vertical grid lines.
0311      *  Default is 30 pixels. */
0312     uint verticalLinesDistance() const;
0313 
0314     /** \brief Set whether the vertical lines move with the data.
0315      *  Default is true. This has no effect is showVerticalLines is false. */
0316     void setVerticalLinesScroll(bool value);
0317     /** \brief Whether the vertical lines move with the data.
0318      *  Default is true. This has no effect is showVerticalLines is false. */
0319     bool verticalLinesScroll() const;
0320 
0321     /** \brief Set whether to draw the horizontal grid lines.
0322      *  Default is true. */
0323     void setShowHorizontalLines(bool value);
0324     /** \brief Whether to draw the horizontal grid lines.
0325      *  Default is true. */
0326     bool showHorizontalLines() const;
0327 
0328     /** \brief The number of decimal places used for the axis labels
0329      *
0330      *  This is calculated based on the current range */
0331     int currentAxisPrecision() const;
0332 
0333     /** \brief Set whether to show the vertical axis labels.
0334      *
0335      * Default is true.
0336      * \sa showAxis(), setAxisFont(), setAxisFontColor(), setMaxAxisTextWidth() */
0337     void setShowAxis(bool show);
0338     /** \brief Whether to show the vertical axis labels.
0339      *
0340      * Default is true.
0341      * \sa setShowAxis(), axisFont(), axisFontColor(), maxAxisTextWidth() */
0342     bool showAxis() const;
0343 
0344     /** \brief Set the filename of the SVG background.
0345      *
0346      * Set to empty (default) to disable again. */
0347     void setSvgBackground(const QString &filename);
0348 
0349     /** \brief The filename of the SVG background. */
0350     QString svgBackground() const;
0351 
0352     /** \brief Return the last value that we have for the given beam index.
0353      *
0354      * \return last value, or 0 if not known. */
0355     qreal lastValue(int index) const;
0356 
0357     /** \brief Return a translated string for the last value at the given index.
0358      *
0359      * Returns, for example,  "34 %" or "100 KB" for the given beam index,
0360      * using the last value set for the beam, using the given precision.
0361      *
0362      * If precision is -1 (the default) then if @p value is greater than 99.5, no decimal figures are shown,
0363      * otherwise if @p value is greater than 0.995, 1 decimal figure is used, otherwise 2.
0364      */
0365     QString lastValueAsString(int index, int precision = -1) const;
0366 
0367     /** \brief Return a translated string for the given value.
0368      *
0369      * Returns, for example, "34 %" or "100 KB" for the given value in unscaled units.
0370      *
0371      * If precision is -1 (the default) then if @p value is greater than 99.5, no decimal figures are shown,
0372      * otherwise if @p value is greater than 0.995, 1 decimal figure is used, otherwise 2.
0373      *
0374      * For example:
0375      * \code
0376      *   KSignalPlotter plotter;
0377      *   plotter.setUnit( ki18ncp("Units", "1 hour", "%1 hours") );
0378      *   plotter.scaleDownBy( 60 ); //The input will be in seconds, and there's 60 seconds in an hour
0379      *   QString formattedString = plotter.valueAsString(150); //returns "2.5 hours"
0380      * \endcode
0381      *
0382      */
0383     QString valueAsString(qreal value, int precision = -1) const;
0384 
0385     /** \brief Set the distance between the left of the widget and the left of the plotting region.
0386      *
0387      *  For example:
0388      *  \code
0389      *      int axisTextWidth = fontMetrics().width(i18nc("Largest axis title", "99999 XXXX"));
0390      *      plotter->setMaxAxisTextWidth(axisTextWidth);
0391      *  \endcode
0392      *
0393      *  If this is 0, the default, then the text will be shown inside the plotting area.
0394      */
0395     void setMaxAxisTextWidth(int maxAxisTextWidth);
0396     /** \brief Get the distance between the left of the widget and the left of the plotting region. */
0397     int maxAxisTextWidth() const;
0398 
0399     /** \brief Set whether to smooth the graph by averaging the points.
0400      *
0401      * This uses the formula:  (value*2 + last_value)/3.
0402      * Default is true. */
0403     void setSmoothGraph(bool smooth);
0404     /** \brief Whether to smooth the graph by averaging the points.
0405      *
0406      * This uses the formula:  (value*2 + last_value)/3.
0407      * Default is true. */
0408     bool smoothGraph() const;
0409 
0410     /** \brief Set whether to stack the beams on top of each other.
0411      *
0412      * Default is false */
0413     void setStackGraph(bool stack);
0414     /** \brief Whether to stack the beams on top of each other.
0415      *
0416      * Default is false */
0417     bool stackGraph() const;
0418 
0419     /** \brief Alpha value for filling the area underneath the graph lines.
0420      *
0421      * Set to 0 to disable filling the graph, and 255 for a solid fill. Default is 20*/
0422     void setFillOpacity(int fill);
0423     /** \brief Alpha value for filling the area underneath the graph lines. */
0424     int fillOpacity() const;
0425 
0426     /* Whether to show a thin line on the left and bottom of the widget, for a slight 3D effect */
0427     bool thinFrame() const;
0428     /* Set whether to show a thin line on the left and bottom of the widget, for a slight 3D effect */
0429     void setThinFrame(bool thinFrame);
0430 
0431 Q_SIGNALS:
0432     /** When the axis has changed this signal is emitted. */
0433     void axisScaleChanged();
0434 
0435 protected:
0436     /* Reimplemented */
0437     void resizeEvent(QResizeEvent *) override;
0438     void paintEvent(QPaintEvent *) override;
0439     QSize sizeHint() const override;
0440     void changeEvent(QEvent *event) override;
0441 
0442 private:
0443     KSignalPlotterPrivate *const d;
0444     friend class KSignalPlotterPrivate;
0445 };
0446 
0447 #endif