A3: Add TrackUtilities.h

Author: njacazio

ALICE3/Core/TrackUtilities.h

@@ -0,0 +1,68 @@
+// Copyright 2019-2020 CERN and copyright holders of ALICE O2.
+// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.
+// All rights not expressly granted are reserved.
+//
+// This software is distributed under the terms of the GNU General Public
+// License v3 (GPL Version 3), copied verbatim in the file "COPYING".
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+///
+/// \file TrackUtilities.h
+///
+/// \brief Set of utilities for the ALICE3 track handling
+///
+/// \since  May 21, 2025
+///
+
+#ifndef ALICE3_CORE_TRACKUTILITIES_H_
+#define ALICE3_CORE_TRACKUTILITIES_H_
+
+#include "ReconstructionDataFormats/Track.h"
+
+namespace o2::upgrade
+{
+
+/// Function to convert a McParticle into a perfect Track
+/// \param particle the particle to convert (mcParticle)
+/// \param o2track the address of the resulting TrackParCov
+template <typename McParticleType>
+void convertMCParticleToO2Track(McParticleType& particle,
+                                o2::track::TrackParCov& o2track,
+                                const o2::framework::Service<o2::framework::O2DatabasePDG>& pdg)
+{
+  auto pdgInfo = pdg->GetParticle(particle.pdgCode());
+  int charge = 0;
+  if (pdgInfo != nullptr) {
+    charge = pdgInfo->Charge() / 3;
+  }
+  std::array<float, 5> params;
+  std::array<float, 15> covm = {0.};
+  float s, c, x;
+  o2::math_utils::sincos(particle.phi(), s, c);
+  o2::math_utils::rotateZInv(particle.vx(), particle.vy(), x, params[0], s, c);
+  params[1] = particle.vz();
+  params[2] = 0.; // since alpha = phi
+  auto theta = 2. * std::atan(std::exp(-particle.eta()));
+  params[3] = 1. / std::tan(theta);
+  params[4] = charge / particle.pt();
+
+  // Initialize TrackParCov in-place
+  new (&o2track)(o2::track::TrackParCov)(x, particle.phi(), params, covm);
+}
+
+/// Function to convert a McParticle into a perfect Track
+/// \param particle the particle to convert (mcParticle)
+/// \param o2track the address of the resulting TrackParCov
+template <typename McParticleType>
+o2::track::TrackParCov convertMCParticleToO2Track(McParticleType& particle,
+                                                  const o2::framework::Service<o2::framework::O2DatabasePDG>& pdg)
+{
+  TrackParCov o2track;
+  convertMCParticleToO2Track(particle, o2track, pdg);
+}
+
+} // namespace o2::upgrade
+
+#endif // ALICE3_CORE_TRACKUTILITIES_H_

ALICE3/TableProducer/OTF/onTheFlyRichPid.cxx

@@ -47,6 +47,7 @@
 #include "Framework/ASoAHelpers.h"
 #include "Common/DataModel/TrackSelectionTables.h"
 #include "Common/Core/trackUtilities.h"
+#include "ALICE3/Core/TrackUtilities.h"
 #include "ReconstructionDataFormats/DCA.h"
 #include "DetectorsBase/Propagator.h"
 #include "DetectorsBase/GeometryManager.h"
@@ -446,34 +447,6 @@ struct OnTheFlyRichPid {
     updateProjectiveParameters();
   }
 
-  /// Function to convert a McParticle into a perfect Track
-  /// \param particle the particle to convert (mcParticle)
-  /// \param o2track the address of the resulting TrackParCov
-  template <typename McParticleType>
-  o2::track::TrackParCov convertMCParticleToO2Track(McParticleType& particle)
-  {
-    // FIXME: this is a fundamentally important piece of code.
-    // It could be placed in a utility file instead of here.
-    auto pdgInfo = pdg->GetParticle(particle.pdgCode());
-    int charge = 0;
-    if (pdgInfo != nullptr) {
-      charge = pdgInfo->Charge() / 3;
-    }
-    std::array<float, 5> params;
-    std::array<float, 15> covm = {0.};
-    float s, c, x;
-    o2::math_utils::sincos(particle.phi(), s, c);
-    o2::math_utils::rotateZInv(particle.vx(), particle.vy(), x, params[0], s, c);
-    params[1] = particle.vz();
-    params[2] = 0.; // since alpha = phi
-    auto theta = 2. * std::atan(std::exp(-particle.eta()));
-    params[3] = 1. / std::tan(theta);
-    params[4] = charge / particle.pt();
-
-    // Return TrackParCov
-    return o2::track::TrackParCov(x, particle.phi(), params, covm);
-  }
-
   /// check if particle reaches radiator
   /// \param track the input track
   /// \param radius the radius of the layer you're calculating the length to
@@ -778,7 +751,7 @@ struct OnTheFlyRichPid {
         continue;
 
       auto mcParticle = track.mcParticle();
-      o2::track::TrackParCov o2track = convertMCParticleToO2Track(mcParticle);
+      o2::track::TrackParCov o2track = o2::upgrade::convertMCParticleToO2Track(mcParticle, pdg);
 
       // float xPv = error_value;
       if (o2track.propagateToDCA(mcPvVtx, dBz)) {

ALICE3/TableProducer/OTF/onTheFlyTofPid.cxx

@@ -40,6 +40,7 @@
 #include "Framework/ASoAHelpers.h"
 #include "Common/DataModel/TrackSelectionTables.h"
 #include "Common/Core/trackUtilities.h"
+#include "ALICE3/Core/TrackUtilities.h"
 #include "ReconstructionDataFormats/DCA.h"
 #include "DetectorsBase/Propagator.h"
 #include "DetectorsBase/GeometryManager.h"
@@ -252,34 +253,6 @@ struct OnTheFlyTofPid {
     }
   }
 
-  /// Function to convert a McParticle into a perfect Track
-  /// \param particle the particle to convert (mcParticle)
-  /// \param o2track the address of the resulting TrackParCov
-  template <typename McParticleType>
-  o2::track::TrackParCov convertMCParticleToO2Track(McParticleType& particle)
-  {
-    // FIXME: this is a fundamentally important piece of code.
-    // It could be placed in a utility file instead of here.
-    auto pdgInfo = pdg->GetParticle(particle.pdgCode());
-    int charge = 0;
-    if (pdgInfo != nullptr) {
-      charge = pdgInfo->Charge() / 3;
-    }
-    std::array<float, 5> params;
-    std::array<float, 15> covm = {0.};
-    float s, c, x;
-    o2::math_utils::sincos(particle.phi(), s, c);
-    o2::math_utils::rotateZInv(particle.vx(), particle.vy(), x, params[0], s, c);
-    params[1] = particle.vz();
-    params[2] = 0.; // since alpha = phi
-    auto theta = 2. * std::atan(std::exp(-particle.eta()));
-    params[3] = 1. / std::tan(theta);
-    params[4] = charge / particle.pt();
-
-    // Return TrackParCov
-    return o2::track::TrackParCov(x, particle.phi(), params, covm);
-  }
-
   /// function to calculate track length of this track up to a certain radius
   /// \param track the input track
   /// \param radius the radius of the layer you're calculating the length to
@@ -519,7 +492,7 @@ struct OnTheFlyTofPid {
         LOG(debug) << "Track without mcParticle found!";
       }
       const auto& mcParticle = track.mcParticle();
-      o2::track::TrackParCov o2track = convertMCParticleToO2Track(mcParticle);
+      o2::track::TrackParCov o2track = o2::upgrade::convertMCParticleToO2Track(mcParticle, pdg);
 
       float xPv = -100.f;
       static constexpr float kTrkXThreshold = -99.f; // Threshold to consider a good propagation of the track

ALICE3/TableProducer/OTF/onTheFlyTracker.cxx

@@ -61,6 +61,7 @@
 #include "ALICE3/Core/DelphesO2TrackSmearer.h"
 #include "ALICE3/Core/FastTracker.h"
 #include "ALICE3/Core/DetLayer.h"
+#include "ALICE3/Core/TrackUtilities.h"
 #include "ALICE3/DataModel/collisionAlice3.h"
 #include "ALICE3/DataModel/tracksAlice3.h"
 #include "ALICE3/DataModel/OTFStrangeness.h"
@@ -520,32 +521,6 @@ struct OnTheFlyTracker {
     new (&o2track)(o2::track::TrackParCov)(x, particle.Phi(), params, covm);
   }
 
-  /// Function to convert a McParticle into a perfect Track
-  /// \param particle the particle to convert (mcParticle)
-  /// \param o2track the address of the resulting TrackParCov
-  template <typename McParticleType>
-  void convertMCParticleToO2Track(McParticleType& particle, o2::track::TrackParCov& o2track)
-  {
-    auto pdgInfo = pdgDB->GetParticle(particle.pdgCode());
-    int charge = 0;
-    if (pdgInfo != nullptr) {
-      charge = pdgInfo->Charge() / 3;
-    }
-    std::array<float, 5> params;
-    std::array<float, 15> covm = {0.};
-    float s, c, x;
-    o2::math_utils::sincos(particle.phi(), s, c);
-    o2::math_utils::rotateZInv(particle.vx(), particle.vy(), x, params[0], s, c);
-    params[1] = particle.vz();
-    params[2] = 0.; // since alpha = phi
-    auto theta = 2. * std::atan(std::exp(-particle.eta()));
-    params[3] = 1. / std::tan(theta);
-    params[4] = charge / particle.pt();
-
-    // Initialize TrackParCov in-place
-    new (&o2track)(o2::track::TrackParCov)(x, particle.phi(), params, covm);
-  }
-
   float dNdEta = 0.f; // Charged particle multiplicity to use in the efficiency evaluation
   void process(aod::McCollision const& mcCollision, aod::McParticles const& mcParticles)
   {
@@ -605,7 +580,7 @@ struct OnTheFlyTracker {
       if (cascadeDecaySettings.decayXi) {
         if (mcParticle.pdgCode() == 3312) {
           o2::track::TrackParCov xiTrackParCov;
-          convertMCParticleToO2Track(mcParticle, xiTrackParCov);
+          o2::upgrade::convertMCParticleToO2Track(mcParticle, xiTrackParCov, pdgDB);
           decayParticle(mcParticle, xiTrackParCov, decayProducts, xiDecayVertex, laDecayVertex);
           xiDecayRadius2D = sqrt(xiDecayVertex[0] * xiDecayVertex[0] + xiDecayVertex[1] * xiDecayVertex[1]);
           laDecayRadius2D = sqrt(laDecayVertex[0] * laDecayVertex[0] + laDecayVertex[1] * laDecayVertex[1]);
@@ -653,7 +628,7 @@ struct OnTheFlyTracker {
       }
 
       o2::track::TrackParCov trackParCov;
-      convertMCParticleToO2Track(mcParticle, trackParCov);
+      o2::upgrade::convertMCParticleToO2Track(mcParticle, trackParCov, pdgDB);
 
       bool isDecayDaughter = false;
       if (mcParticle.getProcess() == 4)