[PWGCF] FemtoUniverse: Add function to fill only MCTruthTracks (#13350)

Author: prchakra

PWGCF/FemtoUniverse/TableProducer/femtoUniverseProducerTask.cxx

@@ -188,6 +188,7 @@ struct FemtoUniverseProducerTask {
     Configurable<std::vector<float>> confTrkDCAzMax{FemtoUniverseTrackSelection::getSelectionName(femto_universe_track_selection::kDCAzMax, "ConfTrk"), std::vector<float>{0.2f}, FemtoUniverseTrackSelection::getSelectionHelper(femto_universe_track_selection::kDCAzMax, "Track selection: ")}; /// \todo Reintegrate PID to the general selection container
     Configurable<std::vector<float>> confTrkPIDnSigmaMax{FemtoUniverseTrackSelection::getSelectionName(femto_universe_track_selection::kPIDnSigmaMax, "ConfTrk"), std::vector<float>{3.5f, 3.f, 2.5f}, FemtoUniverseTrackSelection::getSelectionHelper(femto_universe_track_selection::kPIDnSigmaMax, "Track selection: ")};
     Configurable<std::vector<int>> confTrkPIDspecies{"confTrkPIDspecies", std::vector<int>{o2::track::PID::Pion, o2::track::PID::Kaon, o2::track::PID::Proton, o2::track::PID::Deuteron}, "Trk sel: Particles species for PID (Pion=2, Kaon=3, Proton=4, Deuteron=5)"};
+    Configurable<bool> confIsOnlyMCTrack{"confIsOnlyMCTrack", false, "Enable filling of only MC Tracks"};
     // Numbers from ~/alice/O2/DataFormats/Reconstruction/include/ReconstructionDataFormats/PID.h //static constexpr ID Pion = 2; static constexpr ID Kaon = 3; static constexpr ID Proton = 4; static constexpr ID Deuteron = 5;
   } ConfTrkSelection;
 
@@ -1349,6 +1350,27 @@ struct FemtoUniverseProducerTask {
     }
   }
 
+  template <typename MCParticlesType>
+  void fillTracksMCTruth(MCParticlesType const& mcParticles)
+  {
+    for (const auto& mc : mcParticles) { // Loop over all MC Truth particles
+
+      std::vector<int> childIDs = {0, 0};
+      outputParts(outputCollision.lastIndex(),
+                  mc.pt(),
+                  mc.eta(),
+                  mc.phi(),
+                  aod::femtouniverseparticle::ParticleType::kMCTruthTrack,
+                  0,
+                  0,
+                  mc.pdgCode(),
+                  childIDs,
+                  0,
+                  0);
+      fillMCTruthParticle(mc, aod::femtouniverseparticle::ParticleType::kMCTruthTrack);
+    }
+  }
+
   template <bool isMC, typename CollisionType, typename CascadeType, typename TrackType>
   void fillCascade(CollisionType const& col, CascadeType const& fullCascades, TrackType const&)
   {
@@ -2534,7 +2556,11 @@ struct FemtoUniverseProducerTask {
         if (colcheck) {
           auto groupedMCParticles = mcParticles.sliceBy(perMCCollision, mccol.globalIndex());
           outputCollExtra(1.0, 1.0);
-          fillParticles<decltype(groupedMCParticles), true, true>(groupedMCParticles, recoMcIds); // fills mc particles
+          if (!ConfTrkSelection.confIsOnlyMCTrack) {
+            fillParticles<decltype(groupedMCParticles), true, true>(groupedMCParticles, recoMcIds); // fills mc particles
+          } else {
+            fillTracksMCTruth(groupedMCParticles);
+          }
         }
       }
     }