Add plot divisions control

assets/icons/points.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" height="24px" viewBox="0 0 24 24" width="24px" fill="#000000"><path d="M0 0h24v24H0V0z" fill="none"/><path d="M10 12c-1.1 0-2 .9-2 2s.9 2 2 2 2-.9 2-2-.9-2-2-2zM6 8c-1.1 0-2 .9-2 2s.9 2 2 2 2-.9 2-2-.9-2-2-2zm0 8c-1.1 0-2 .9-2 2s.9 2 2 2 2-.9 2-2-.9-2-2-2zm12-8c1.1 0 2-.9 2-2s-.9-2-2-2-2 .9-2 2 .9 2 2 2zm-4 8c-1.1 0-2 .9-2 2s.9 2 2 2 2-.9 2-2-.9-2-2-2zm4-4c-1.1 0-2 .9-2 2s.9 2 2 2 2-.9 2-2-.9-2-2-2zm-4-4c-1.1 0-2 .9-2 2s.9 2 2 2 2-.9 2-2-.9-2-2-2zm-4-4c-1.1 0-2 .9-2 2s.9 2 2 2 2-.9 2-2-.9-2-2-2z"/></svg>

assets/icons/rcc_icons.qrc

@@ -72,5 +72,6 @@
         <file>show-all.svg</file>
         <file>hide-all.svg</file>
         <file>multiplot.svg</file>
+        <file>points.svg</file>
     </qresource>
 </RCC>

assets/qml/Dashboard/ViewOptions.qml

@@ -23,6 +23,7 @@
 import QtQuick
 import QtQuick.Layouts
 import QtQuick.Controls
+import Qt.labs.settings 1.0
 
 import "../Widgets" as Widgets
 
@@ -38,6 +39,40 @@ Widgets.Window {
     icon.source: "qrc:/icons/visibility.svg"
     backgroundColor: Cpp_ThemeManager.embeddedWindowBackground
 
+    //
+    // Maps the slider position to points
+    // https://stackoverflow.com/a/846249
+    //
+    function logslider(position) {
+        var minp = 0
+        var maxp = 100
+        var minv = Math.log(10)
+        var maxv = Math.log(10000)
+        var scale = (maxv - minv) / (maxp - minp);
+        return Math.exp(minv + scale * (position - minp)).toFixed(0);
+    }
+
+    //
+    // Maps the points value to the slider position
+    // https://stackoverflow.com/a/846249
+    //
+    function logposition(value) {
+        var minp = 0
+        var maxp = 100
+        var minv = Math.log(10)
+        var maxv = Math.log(10000)
+        var scale = (maxv - minv) / (maxp - minp)
+        var result = (Math.log(value) - minv) / scale + minp;
+        return result.toFixed(0)
+    }
+
+    //
+    // Settings
+    //
+    Settings {
+        property alias points: dial.value
+    }
+
     //
     // Put all items inside a scrollview
     //
@@ -53,6 +88,7 @@ Widgets.Window {
         // Main layout
         //
         ColumnLayout {
+            id: layout
             x: app.spacing
             spacing: app.spacing / 2
             width: parent.width - 10 - 2 * app.spacing
@@ -64,6 +100,57 @@ Widgets.Window {
                 height: app.spacing
             }
 
+            //
+            // Horizontal range title
+            //
+            RowLayout {
+                spacing: app.spacing
+                Layout.fillWidth: true
+                visible: Cpp_UI_Dashboard.plotCount > 0 || Cpp_UI_Dashboard.multiPlotCount > 0
+
+                Widgets.Icon {
+                    width: 18
+                    height: 18
+                    color: palette.text
+                    source: "qrc:/icons/points.svg"
+                }
+
+                Label {
+                    font.bold: true
+                    text: qsTr("Plot divisions (%1)").arg(logslider(dial.value))
+                }
+
+                Item {
+                    Layout.fillWidth: true
+                }
+            }
+
+            //
+            // Horizontal scale controls
+            //
+            Dial {
+                id: dial
+                to: 100
+                from: 10
+                value: logposition(100)
+                Layout.fillWidth: true
+                Layout.alignment: Qt.AlignVCenter
+                visible: Cpp_UI_Dashboard.plotCount > 0 || Cpp_UI_Dashboard.multiPlotCount > 0
+
+                onValueChanged: {
+                    var log = logslider(value)
+                    if (Cpp_UI_Dashboard.points !== log)
+                        Cpp_UI_Dashboard.points = log
+                }
+            }
+
+            //
+            // Spacer
+            //
+            Item {
+                height: app.spacing
+            }
+
             //
             // Groups
             //

src/UI/Dashboard.cpp

@@ -43,7 +43,8 @@ static Dashboard *INSTANCE = nullptr;
  * Constructor of the class.
  */
 Dashboard::Dashboard()
-    : m_latestJsonFrame(JFI_Empty())
+    : m_points(100),
+      m_latestJsonFrame(JFI_Empty())
 {
     auto cp = CSV::Player::getInstance();
     auto io = IO::Manager::getInstance();
@@ -108,6 +109,13 @@ bool Dashboard::available()
     return totalWidgetCount() > 0;
 }
 
+/**
+ * Returns the number of points displayed by the graphs
+ */
+int Dashboard::points() const {
+    return m_points;
+}
+
 /**
  * Returns @c true if the current JSON frame is valid and ready-to-use by the QML
  * interface.
@@ -494,6 +502,17 @@ QVector<QString> Dashboard::multiPlotTitles() const     { return groupTitles(m_m
 QVector<QString> Dashboard::accelerometerTitles() const { return groupTitles(m_accelerometerWidgets); }
 // clang-format on
 
+//--------------------------------------------------------------------------------------------------
+// Plot options
+//--------------------------------------------------------------------------------------------------
+
+void Dashboard::setPoints(const int points) {
+    if (m_points != points) {
+        m_points = points;
+        emit pointsChanged();
+    }
+}
+
 //--------------------------------------------------------------------------------------------------
 // Visibility-related slots
 //--------------------------------------------------------------------------------------------------

src/UI/Dashboard.h

@@ -40,6 +40,10 @@ class Dashboard : public QObject
     Q_PROPERTY(bool available
                READ available
                NOTIFY widgetCountChanged)
+    Q_PROPERTY(int points
+               READ points
+               WRITE setPoints
+               NOTIFY pointsChanged)
     Q_PROPERTY(int totalWidgetCount
                READ totalWidgetCount
                NOTIFY widgetCountChanged)
@@ -103,6 +107,7 @@ signals:
     void updated();
     void dataReset();
     void titleChanged();
+    void pointsChanged();
     void widgetCountChanged();
     void widgetVisibilityChanged();
 
@@ -137,6 +142,7 @@ public:
 
     QString title();
     bool available();
+    int points() const;
 
     int totalWidgetCount() const;
     int mapCount() const;
@@ -177,6 +183,7 @@ public:
     QVector<QString> accelerometerTitles() const;
 
 public slots:
+    void setPoints(const int points);
     void setBarVisible(const int index, const bool visible);
     void setMapVisible(const int index, const bool visible);
     void setPlotVisible(const int index, const bool visible);
@@ -210,6 +217,8 @@ private:
                                     const int index);
 
 private:
+    int m_points;
+
     QVector<bool> m_barVisibility;
     QVector<bool> m_mapVisibility;
     QVector<bool> m_plotVisibility;

src/Widgets/Plot.cpp

@@ -61,17 +61,8 @@ Plot::Plot(const int index)
     m_layout.setContentsMargins(24, 24, 24, 24);
     setLayout(&m_layout);
 
-    // Add 100 points to the plot
-    m_xData.reserve(100);
-    m_yData.reserve(100);
-    for (int i = 0; i < 100; ++i)
-    {
-        m_xData.append(i);
-        m_yData.append(0);
-    }
-
     // Create curve from data
-    m_curve.setSamples(m_xData, m_yData);
+    updateRange();
     m_curve.attach(&m_plot);
     m_plot.replot();
     m_plot.show();
@@ -108,6 +99,7 @@ Plot::Plot(const int index)
 
     // React to dashboard events
     connect(dash, SIGNAL(updated()), this, SLOT(updateData()));
+    connect(dash, SIGNAL(pointsChanged()), this, SLOT(updateRange()));
 }
 
 void Plot::updateData()
@@ -141,3 +133,22 @@ void Plot::updateData()
         m_plot.replot();
     }
 }
+
+void Plot::updateRange() {
+    // Get pointer to dashboard manager
+    auto dash = UI::Dashboard::getInstance();
+
+    // Set number of points
+    m_xData.clear();
+    m_yData.clear();
+    m_xData.reserve(dash->points());
+    m_yData.reserve(dash->points());
+    for (int i = 0; i < dash->points(); ++i)
+    {
+        m_xData.append(i);
+        m_yData.append(0);
+    }
+
+    // Create curve from data
+    m_curve.setSamples(m_xData, m_yData);
+}

src/Widgets/Plot.h

@@ -40,6 +40,7 @@ public:
 
 private slots:
     void updateData();
+    void updateRange();
 
 private:
     int m_index;