Fixed very bad plot bugs preventing correct plotting, made QGC suspectible to plot crashes

src/ui/QGCDataPlot2D.cc

@@ -375,10 +375,25 @@ void QGCDataPlot2D::loadCsvLog(QString file, QString xAxisName, QString yAxisFil
     // Clear plot
     plot->removeData();
 
-    QVector<double> xValues;
+    QMap<QString, QVector<double>* > xValues;
     QMap<QString, QVector<double>* > yValues;
 
     curveNames.append(header.split(separator, QString::SkipEmptyParts));
+
+    // Eliminate any non-string curve names
+    for (int i = 0; i < curveNames.count(); ++i)
+    {
+        if (curveNames.at(i).length() == 0 ||
+            curveNames.at(i) == " " ||
+            curveNames.at(i) == "\n" ||
+            curveNames.at(i) == "\t" ||
+            curveNames.at(i) == "\r")
+        {
+            // Remove bogus curve name
+            curveNames.removeAt(i);
+        }
+    }
+
     QString curveName;
 
     // Clear UI elements
@@ -408,6 +423,7 @@ void QGCDataPlot2D::loadCsvLog(QString file, QString xAxisName, QString yAxisFil
         if (curveName != xAxisFilter) {
             if ((yAxisFilter == "") || yAxisFilter.contains(curveName)) {
                 yValues.insert(curveName, new QVector<double>());
+                xValues.insert(curveName, new QVector<double>());
                 // Add separator starting with second item
                 if (curveNameIndex > 0 && curveNameIndex < curveNames.count()) {
                     ui->yAxis->setText(ui->yAxis->text()+"|");
@@ -425,29 +441,58 @@ void QGCDataPlot2D::loadCsvLog(QString file, QString xAxisName, QString yAxisFil
 
     double x,y;
 
-    while (!in.atEnd()) {
+    while (!in.atEnd())
+    {
         QString line = in.readLine();
 
-        QStringList values = line.split(separator, QString::SkipEmptyParts);
+        // Keep empty parts here - we still have to act on them
+        QStringList values = line.split(separator, QString::KeepEmptyParts);
 
-        foreach(curveName, curveNames) {
-            bool okx;
-            if (curveName == xAxisFilter) {
+        bool headerfound = false;
+
+        // First get header - ORDER MATTERS HERE!
+        foreach(curveName, curveNames)
+        {
+            if (curveName == xAxisFilter)
+            {
                 // X  AXIS HANDLING
 
                 // Take this value as x if it is selected
-                x = values.at(curveNames.indexOf(curveName)).toDouble(&okx);
-                xValues.append(x);// - 1270125570000ULL);
-            } else {
-                // Y  AXIS HANDLING
+                QString text = values.at(curveNames.indexOf(curveName));
+                text = text.trimmed();
+                if (text.length() > 0 && text != " " && text != "\n" && text != "\r" && text != "\t")
+                {
+                    bool okx = true;
+                    x = text.toDouble(&okx);
+                    if (okx && !isnan(x) && !isinf(x))
+                    {
+                        headerfound = true;
+                    }
+                }
+            }
+        }
 
-                if(yAxisFilter == "" || yAxisFilter.contains(curveName)) {
-                    // Only append y values where a valid x value is present
-                    if (yValues.value(curveName)->count() == xValues.count() - 1) {
+        if (headerfound)
+        {
+            // Search again from start for values - ORDER MATTERS HERE!
+            foreach(curveName, curveNames)
+            {
+                // Y  AXIS HANDLING
+                if(curveName != xAxisFilter && (yAxisFilter == "" || yAxisFilter.contains(curveName)))
+                {
                     bool oky;
                     int curveNameIndex = curveNames.indexOf(curveName);
-                        if (values.count() > curveNameIndex) {
-                            y = values.at(curveNameIndex).toDouble(&oky);
+                    if (values.count() > curveNameIndex)
+                    {
+                        QString text(values.at(curveNameIndex));
+                        text = text.trimmed();
+                        y = text.toDouble(&oky);
+                        // Only INF is really an issue for the plot
+                        // NaN is fine
+                        if (oky && !isnan(y) && !isinf(y) && text.length() > 0 && text != " " && text != "\n" && text != "\r" && text != "\t")
+                        {
+                            // Only append definitely valid values
+                            xValues.value(curveName)->append(x);
                             yValues.value(curveName)->append(y);
                         }
                     }
@@ -459,8 +504,9 @@ void QGCDataPlot2D::loadCsvLog(QString file, QString xAxisName, QString yAxisFil
     // Add data array of each curve to the plot at once (fast)
     // Iterates through all x-y curve combinations
     for (int i = 0; i < yValues.count(); i++) {
-        plot->appendData(yValues.keys().at(i), xValues.data(), yValues.values().at(i)->data(), xValues.count());
+        plot->appendData(yValues.keys().at(i), xValues.values().at(i)->data(), yValues.values().at(i)->data(), xValues.values().at(i)->count());
     }
+    plot->updateScale();
     plot->setStyleText(ui->style->currentText());
 }
 

src/ui/linechart/IncrementalPlot.cc

@@ -259,9 +259,9 @@ void IncrementalPlot::resetScaling()
 void IncrementalPlot::updateScale()
 {
     const double margin = 0.05;
-    double xMinRange = xmin+(xmin*margin);
+    double xMinRange = xmin-(xmin*margin);
     double xMaxRange = xmax+(xmax*margin);
-    double yMinRange = ymin+(ymin*margin);
+    double yMinRange = ymin-(ymin*margin);
     double yMaxRange = ymax+(ymax*margin);
     if (symmetric) {
         double xRange = xMaxRange - xMinRange;