TPC: Add function to adjust width of the color axis

Author: wiechula

Detectors/TPC/base/include/TPCBase/Painter.h

@@ -190,6 +190,12 @@ TH3F convertCalDetToTH3(const std::vector<CalDet<DataT>>& calDet, const bool nor
 /// make summary canvases for laser calibration data
 std::vector<TCanvas*> makeSummaryCanvases(const LtrCalibData& ltr, std::vector<TCanvas*>* outputCanvases = nullptr);
 
+/// Adjust the X2 position and the tick length of the color axis
+/// \param h histogram to get z axis
+/// \param x2ndc new x2 value of color axis in NDC
+/// \param tickLength tick length of the color axis
+void adjustPalette(TH1* h, float x2ndc, float tickLength = 0.015);
+
 } // namespace painter
 
 } // namespace o2::tpc

Detectors/TPC/base/src/Painter.cxx

@@ -24,6 +24,7 @@
 #include "TLatex.h"
 #include "TStyle.h"
 #include "TPaveText.h"
+#include "TPaletteAxis.h"
 
 #include "DataFormatsTPC/Defs.h"
 #include "TPCBase/ROC.h"
@@ -931,6 +932,16 @@ std::vector<TCanvas*> painter::makeSummaryCanvases(const LtrCalibData& ltr, std:
   return vecCanvases;
 }
 
+void painter::adjustPalette(TH1* h, float x2ndc, float tickLength)
+{
+  gPad->Modified();
+  gPad->Update();
+  auto palette = (TPaletteAxis*)h->GetListOfFunctions()->FindObject("palette");
+  palette->SetX2NDC(x2ndc);
+  auto ax = h->GetZaxis();
+  ax->SetTickLength(tickLength);
+}
+
 // ===| explicit instantiations |===============================================
 // this is required to force the compiler to create instances with the types
 // we usually would like to deal with