RangeUtils: Added MPL Inferno as default color gradient

This MR resolves #273 (closed)

GUI/Model/Data/IntensityDataItem.cpp

@@ -21,6 +21,7 @@
 #include "GUI/Model/Device/MaskUnitsConverter.h"
 #include "GUI/Support/IO/ImportDataInfo.h"
 #include "GUI/Support/Util/Error.h"
+#include "GUI/View/PlotUtil/RangeUtils.h"
 #include <qcustomplot.h>
 
 namespace {
@@ -36,6 +37,8 @@ const QString ProjectionContainer("ProjectionContainer");
 
 } // namespace Tag
 
+QCPColorGradient infernoGradient = GUI::View::RangeUtils::colorGradientInferno();
+
 // gradient map for colormaps
 const QMap<QString, QCPColorGradient::GradientPreset> gradient_map = {
     {"Grayscale", QCPColorGradient::gpGrayscale},
@@ -51,14 +54,17 @@ const QMap<QString, QCPColorGradient::GradientPreset> gradient_map = {
     {"Jet", QCPColorGradient::gpJet},
     {"Hues", QCPColorGradient::gpHues}};
 
-QString startGradient = gradient_map.key(QCPColorGradient::gpThermal);
+const QMap<QString, QCPColorGradient> custom_gradient_map = {{"Inferno", infernoGradient}};
+
+QString startGradient = "Inferno";
 
 } // namespace
 
 IntensityDataItem::IntensityDataItem()
     : DataItem(M_TYPE)
     , m_isInterpolated(true)
-    , m_gradient(ComboProperty::fromList(gradient_map.keys(), startGradient))
+    , m_gradient(
+          ComboProperty::fromList(gradient_map.keys() + custom_gradient_map.keys(), startGradient))
     , m_zAxis(std::make_unique<AmplitudeAxisItem>())
 {
 }
@@ -144,7 +150,10 @@ void IntensityDataItem::copyZRangeFromItem(DataItem* sourceItem)
 
 QCPColorGradient IntensityDataItem::currentGradientQCP() const
 {
-    return gradient_map.value(currentGradient());
+    if (gradient_map.contains(currentGradient()))
+        return gradient_map.value(currentGradient());
+    else
+        return custom_gradient_map.value(currentGradient());
 }
 
 QString IntensityDataItem::currentGradient() const