Linechart - Make it possible to change time axis range

src/ui/linechart/LinechartPlot.cc

@@ -566,13 +566,29 @@ quint64 LinechartPlot::getPlotInterval()
  **/
 void LinechartPlot::setPlotInterval(int interval)
 {
-    plotInterval = interval;
+    //Only ever increase the amount of stored data,
+    // so that we allow the user to change between
+    // different intervals without constantly losing
+    // data points
+    if((unsigned)interval > plotInterval) {
+
         QMap<QString, TimeSeriesData*>::iterator j;
         for(j = data.begin(); j != data.end(); ++j)
         {
             TimeSeriesData* d = data.value(j.key());
             d->setInterval(interval);
         }
+    }
+    plotInterval = interval;
+    if(plotInterval > 5*60*1000) //If the interval is longer than 4 minutes, change the time scale step to 2 minutes
+        timeScaleStep = 2*60*1000;
+    else if(plotInterval >= 4*60*1000) //If the interval is longer than 4 minutes, change the time scale step to 1 minutes
+        timeScaleStep = 1*60*1000;
+    else if(plotInterval >= 60*1000) //If the interval is longer than a minute, change the time scale step to 30 seconds
+        timeScaleStep = 30*1000;
+    else
+        timeScaleStep = DEFAULT_SCALE_INTERVAL;
+
 }
 
 /**

src/ui/linechart/LinechartWidget.cc

@@ -207,10 +207,9 @@ void LinechartWidget::createLayout()
     createActions();
 
     // Setup the plot group box area layout
-    QGridLayout* layout = new QGridLayout(ui.diagramGroupBox);
-    mainLayout = layout;
-    layout->setSpacing(4);
-    layout->setMargin(2);
+    QVBoxLayout* vlayout = new QVBoxLayout(ui.diagramGroupBox);
+    vlayout->setSpacing(4);
+    vlayout->setMargin(2);
 
     // Create plot container widget
     activePlot = new LinechartPlot(this, sysid);
@@ -221,9 +220,10 @@ void LinechartWidget::createLayout()
     //    activePlot = getPlot(0);
     //    plotContainer->setPlot(activePlot);
 
-    layout->addWidget(activePlot, 0, 0, 1, 6);
-    layout->setRowStretch(0, 10);
-    layout->setRowStretch(1, 1);
+    vlayout->addWidget(activePlot);
+
+    QHBoxLayout *hlayout = new QHBoxLayout;
+    vlayout->addLayout(hlayout);
 
     // Logarithmic scaling button
     scalingLogButton = createButton(this);
@@ -231,8 +231,7 @@ void LinechartWidget::createLayout()
     scalingLogButton->setCheckable(true);
     scalingLogButton->setToolTip(tr("Set logarithmic scale for Y axis"));
     scalingLogButton->setWhatsThis(tr("Set logarithmic scale for Y axis"));
-    layout->addWidget(scalingLogButton, 1, 0);
-    layout->setColumnStretch(0, 0);
+    hlayout->addWidget(scalingLogButton);
 
     // Averaging spin box
     averageSpinBox = new QSpinBox(this);
@@ -242,8 +241,7 @@ void LinechartWidget::createLayout()
     averageSpinBox->setValue(200);
     setAverageWindow(200);
     averageSpinBox->setMaximum(9999);
-    layout->addWidget(averageSpinBox, 1, 1);
-    layout->setColumnStretch(1, 0);
+    hlayout->addWidget(averageSpinBox);
     connect(averageSpinBox, SIGNAL(valueChanged(int)), this, SLOT(setAverageWindow(int)));
 
     // Log Button
@@ -251,8 +249,7 @@ void LinechartWidget::createLayout()
     logButton->setToolTip(tr("Start to log curve data into a CSV or TXT file"));
     logButton->setWhatsThis(tr("Start to log curve data into a CSV or TXT file"));
     logButton->setText(tr("Start Logging"));
-    layout->addWidget(logButton, 1, 2);
-    layout->setColumnStretch(2, 0);
+    hlayout->addWidget(logButton);
     connect(logButton, SIGNAL(clicked()), this, SLOT(startLogging()));
 
     // Ground time button
@@ -260,17 +257,37 @@ void LinechartWidget::createLayout()
     timeButton->setText(tr("Ground Time"));
     timeButton->setToolTip(tr("Overwrite timestamp of data from vehicle with ground receive time. Helps if the plots are not visible because of missing or invalid onboard time."));
     timeButton->setWhatsThis(tr("Overwrite timestamp of data from vehicle with ground receive time. Helps if the plots are not visible because of missing or invalid onboard time."));
-    layout->addWidget(timeButton, 1, 3);
-    layout->setColumnStretch(3, 0);
+    hlayout->addWidget(timeButton);
     connect(timeButton, SIGNAL(clicked(bool)), activePlot, SLOT(enforceGroundTime(bool)));
     connect(timeButton, SIGNAL(clicked()), this, SLOT(writeSettings()));
 
+    hlayout->addStretch();
+
+    QLabel *timeScaleLabel = new QLabel("Time axis:");
+    hlayout->addWidget(timeScaleLabel);
+
+    timeScaleCmb = new QComboBox(this);
+    timeScaleCmb->addItem("10 seconds", 10);
+    timeScaleCmb->addItem("20 seconds", 20);
+    timeScaleCmb->addItem("30 seconds", 30);
+    timeScaleCmb->addItem("40 seconds", 40);
+    timeScaleCmb->addItem("50 seconds", 50);
+    timeScaleCmb->addItem("1 minute", 60);
+    timeScaleCmb->addItem("2 minutes", 60*2);
+    timeScaleCmb->addItem("3 minutes", 60*3);
+    timeScaleCmb->addItem("4 minutes", 60*4);
+    timeScaleCmb->addItem("5 minutes", 60*5);
+    timeScaleCmb->addItem("10 minutes", 60*10);
+    //timeScaleCmb->setSizeAdjustPolicy(QComboBox::AdjustToContents);
+    timeScaleCmb->setMinimumContentsLength(12);
+
+    hlayout->addWidget(timeScaleCmb);
+    connect(timeScaleCmb, SIGNAL(currentIndexChanged(int)), this, SLOT(timeScaleChanged(int)));
+
     // Initialize the "Show units" checkbox. This is configured in the .ui file, so all
     // we do here is attach the clicked() signal.
     connect(ui.showUnitsCheckBox, SIGNAL(clicked()), this, SLOT(writeSettings()));
 
-    ui.diagramGroupBox->setLayout(layout);
-
     // Add actions
     averageSpinBox->setValue(activePlot->getAverageWindow());
 
@@ -288,6 +305,11 @@ void LinechartWidget::createLayout()
     connect(scalingLogButton, SIGNAL(toggled(bool)), this, SLOT(toggleLogarithmicScaling(bool)));
 }
 
+void LinechartWidget::timeScaleChanged(int index)
+{
+    activePlot->setPlotInterval(timeScaleCmb->itemData(index).toInt()*1000);
+}
+
 void LinechartWidget::toggleLogarithmicScaling(bool checked)
 {
     if(checked)

src/ui/linechart/LinechartWidget.h

@@ -123,6 +123,10 @@ public slots:
     /** @brief Select all curves */
     void selectAllCurves(bool all);
 
+private slots:
+    /** Called when the user changes the time scale combobox. */
+    void timeScaleChanged(int index);
+
 protected:
     void addCurveToList(QString curve);
     void removeCurveFromList(QString curve);
@@ -156,7 +160,7 @@ protected:
     QAction* addNewCurve;                 ///< Add curve candidate to the active curves
 
     QMenu* curveMenu;
-    QGridLayout* mainLayout;
+    QComboBox *timeScaleCmb;
 
     QToolButton* scalingLogButton;
     QToolButton* logButton;