feat: persist ACTS barcodes in G4 sim

Examples/Algorithms/Geant4/include/ActsExamples/Geant4/EventStoreRegistry.hpp

@@ -42,6 +42,12 @@ class EventStoreRegistry {
     std::unordered_map<size_t, Acts::RecordedMaterialTrack> materialTracks;
     /// Particle hit count (for hit indexing)
     std::unordered_map<SimBarcode, std::size_t> particleHitCount;
+    /// Track ID to Barcode mapping
+    std::unordered_map<unsigned int, SimBarcode> trackIdMapping;
+    /// Track ID to root Track ID mapping
+    std::unordered_map<unsigned int, unsigned int> trackIdRootId;
+    /// Track ID generation counter
+    std::unordered_map<unsigned int, unsigned int> trackIdGenerationCount;
   };
 
   EventStoreRegistry() = delete;

Examples/Algorithms/Geant4/src/Geant4Simulation.cpp

@@ -168,33 +168,30 @@ ActsExamples::ProcessCode ActsExamples::Geant4Simulation::execute(
   if (not m_cfg.outputParticlesInitial.empty() and
       not m_cfg.outputParticlesFinal.empty()) {
     // Initial state of particles
-    SimParticleContainer outputParticlesInitial;
-    outputParticlesInitial.insert(eventData.particlesInitial.begin(),
-                                  eventData.particlesInitial.end());
     // Register to the event store
     ctx.eventStore.add(m_cfg.outputParticlesInitial,
-                       std::move(outputParticlesInitial));
+                       SimParticleContainer(eventData.particlesInitial.begin(),
+                                            eventData.particlesInitial.end()));
     // Final state of particles
-    SimParticleContainer outputParticlesFinal;
-    outputParticlesFinal.insert(eventData.particlesFinal.begin(),
-                                eventData.particlesFinal.end());
     // Register to the event store
     ctx.eventStore.add(m_cfg.outputParticlesFinal,
-                       std::move(outputParticlesFinal));
+                       SimParticleContainer(eventData.particlesFinal.begin(),
+                                            eventData.particlesFinal.end()));
   }
 
   // Output handling: Simulated hits
   if (not m_cfg.outputSimHits.empty()) {
-    SimHitContainer simHits;
-    simHits.insert(eventData.hits.begin(), eventData.hits.end());
     // Register to the event store
-    ctx.eventStore.add(m_cfg.outputSimHits, std::move(simHits));
+    ctx.eventStore.add(
+        m_cfg.outputSimHits,
+        SimHitContainer(eventData.hits.begin(), eventData.hits.end()));
   }
 
   // Output handling: Material tracks
   if (not m_cfg.outputMaterialTracks.empty()) {
-    ctx.eventStore.add(m_cfg.outputMaterialTracks,
-                       std::move(eventData.materialTracks));
+    ctx.eventStore.add(
+        m_cfg.outputMaterialTracks,
+        decltype(eventData.materialTracks)(eventData.materialTracks));
   }
 
   return ActsExamples::ProcessCode::SUCCESS;

Examples/Algorithms/Geant4/src/ParticleTrackingAction.cpp

@@ -36,6 +36,8 @@ void ActsExamples::ParticleTrackingAction::PostUserTrackingAction(
 
 ActsExamples::SimParticle ActsExamples::ParticleTrackingAction::convert(
     const G4Track& aTrack) const {
+  auto& eventData = EventStoreRegistry::eventData();
+
   // Unit conversions G4->::ACTS
   constexpr double convertTime = Acts::UnitConstants::s / CLHEP::s;
   constexpr double convertLength = Acts::UnitConstants::mm / CLHEP::mm;
@@ -47,12 +49,34 @@ ActsExamples::SimParticle ActsExamples::ParticleTrackingAction::convert(
   G4double charge = particleDef->GetPDGCharge();
   G4int pdg = particleDef->GetPDGEncoding();
   G4int id = aTrack.GetTrackID();
+  G4int parentId = aTrack.GetParentID();
   G4ThreeVector pPosition = convertLength * aTrack.GetPosition();
   G4double pTime = convertTime * aTrack.GetGlobalTime();
   G4ThreeVector pDirection = aTrack.GetMomentumDirection();
   G4double p = convertEnergy * aTrack.GetKineticEnergy();
+
+  if (parentId != 0) {
+    eventData.trackIdRootId[id] = eventData.trackIdRootId[parentId];
+  } else {
+    eventData.trackIdRootId[id] = id;
+  }
+
+  SimBarcode particleId;
+  if (eventData.trackIdMapping.find(id) != eventData.trackIdMapping.end()) {
+    particleId = eventData.trackIdMapping[id];
+  } else {
+    if (eventData.trackIdRootId.find(id) != eventData.trackIdRootId.end()) {
+      auto rootId = eventData.trackIdRootId[id];
+      particleId = eventData.trackIdMapping[rootId];
+      particleId.setGeneration(++eventData.trackIdGenerationCount[rootId]);
+      eventData.trackIdMapping[id] = particleId;
+    } else {
+      ACTS_WARNING("could not find parent " << parentId << " of " << id);
+    }
+  }
+
   // Now create the Particle
-  ActsExamples::SimParticle aParticle(SimBarcode(id), Acts::PdgParticle(pdg),
+  ActsExamples::SimParticle aParticle(particleId, Acts::PdgParticle(pdg),
                                       charge, mass);
   aParticle.setPosition4(pPosition[0], pPosition[1], pPosition[2], pTime);
   aParticle.setDirection(pDirection[0], pDirection[1], pDirection[2]);

Examples/Algorithms/Geant4/src/SensitiveSteppingAction.cpp

@@ -30,6 +30,9 @@ void ActsExamples::SensitiveSteppingAction::UserSteppingAction(
   constexpr double convertLength = Acts::UnitConstants::mm / CLHEP::mm;
   constexpr double convertEnergy = Acts::UnitConstants::GeV / CLHEP::GeV;
 
+  // Retrieve the event data registry
+  auto& eventData = EventStoreRegistry::eventData();
+
   // The particle after the step
   G4Track* track = step->GetTrack();
   G4PrimaryParticle* primaryParticle =
@@ -101,14 +104,12 @@ void ActsExamples::SensitiveSteppingAction::UserSteppingAction(
     Acts::GeometryIdentifier::Value sGeoVal = std::stoul(volumeName);
     Acts::GeometryIdentifier geoID(sGeoVal);
 
-    SimBarcode particleID(track->GetTrackID());
+    auto particleID = eventData.trackIdMapping[track->GetTrackID()];
+
     Acts::Vector4 particlePosition(hX, hY, hZ, hT);
     Acts::Vector4 beforeMomentum(mXpre, mYpre, mZpre, mEpre);
     Acts::Vector4 afterMomentum(mXpost, mYpost, mZpost, mEpost);
 
-    // Retrieve the event data registry
-    auto& eventData = EventStoreRegistry::eventData();
-
     // Increase counter (starts at 1 because of ++)
     ++eventData.particleHitCount[particleID];
 

Examples/Algorithms/Geant4/src/SimParticleTranslation.cpp

@@ -65,30 +65,33 @@ void ActsExamples::SimParticleTranslation::GeneratePrimaries(G4Event* anEvent) {
   G4PrimaryVertex* pVertex = nullptr;
 
   // We are looping through the particles and flush per vertex
-  std::unique_ptr<SimParticle::Vector4> lastVertex = nullptr;
+  std::optional<Acts::Vector4> lastVertex;
 
   constexpr double convertLength = CLHEP::mm / Acts::UnitConstants::mm;
   constexpr double convertEnergy = CLHEP::GeV / Acts::UnitConstants::GeV;
 
   unsigned int pCounter = 0;
+  unsigned int trackId = 1;
   // Loop over the input partilces and run
   for (const auto& part : inputParticles) {
     auto currentVertex = part.fourPosition();
-    if (lastVertex == nullptr or not currentVertex.isApprox(*lastVertex)) {
+    if (not lastVertex or not currentVertex.isApprox(*lastVertex)) {
       // Add the vertex to the event
       if (pVertex != nullptr) {
         anEvent->AddPrimaryVertex(pVertex);
         ACTS_DEBUG("Flushing " << pCounter
                                << " particles associated with vertex "
-                               << Acts::toString(*lastVertex));
+                               << lastVertex->transpose());
         pCounter = 0;
       }
-      lastVertex = std::make_unique<SimParticle::Vector4>(currentVertex);
+      lastVertex = currentVertex;
       pVertex = new G4PrimaryVertex(
           currentVertex[0] * convertLength, currentVertex[1] * convertLength,
           currentVertex[2] * convertLength, currentVertex[3]);
     }
+
     // Add a new primary to the vertex
+
     Acts::Vector4 mom4 = part.fourMomentum() * convertEnergy;
 
     // Particle properties, may be forced to specific value
@@ -132,15 +135,19 @@ void ActsExamples::SimParticleTranslation::GeneratePrimaries(G4Event* anEvent) {
     particle->SetMass(particleMass);
     particle->Set4Momentum(mom4[0], mom4[1], mom4[2], mom4[3]);
     particle->SetCharge(part.charge());
-    particle->SetTrackID(pCounter);
+    particle->SetTrackID(trackId++);
+
     // Add the primary to the vertex
     pVertex->SetPrimary(particle);
+
+    eventData.trackIdMapping[particle->GetTrackID()] = part.particleId();
+
     ++pCounter;
   }
   // Final vertex to be added
   if (pVertex != nullptr) {
     anEvent->AddPrimaryVertex(pVertex);
     ACTS_DEBUG("Flushing " << pCounter << " particles associated with vertex "
-                           << Acts::toString(*lastVertex));
+                           << lastVertex->transpose());
   }
 }

Examples/Python/tests/root_file_hashes.txt

@@ -2,9 +2,9 @@ test_pythia8__pythia8_particles.root: 7bae8c6353d792ea2d54401334e2e57e486ec154ee
 test_fatras__fatras_particles_final.root: 7ce243ae0e64b13d1f14c7b40f7d6a3bf9edd799f15bf0745b0b08c16ff11bf4
 test_fatras__fatras_particles_initial.root: c72be956b187ea67cb5efe8fed6f7cdd6657631d25aa68105bcfe5af5baecc41
 test_fatras__hits.root: 2f25d996715c6ed05e65a3f36df559de52e0a6c8ab9641fedd810474eaf5db11
-test_geant4__fatras_particles_final.root: 944eed8b749e48031cd8332f7a6994880bd2f381b93d10e887e1e86387c3e5c3
-test_geant4__fatras_particles_initial.root: 161525bb3c62cf9746f5b0528e2d65e9f6d32a4e015a52e2e6d8c6feb13d7753
-test_geant4__hits.root: 3949a5c201c874c1366a09473c024986dc231baf8279b202107785c4fffb0347
+test_geant4__fatras_particles_final.root: b6254065a9bf03fe538d8b39615bfb3936a5e3eef28c4ad67d59514b170d4f87
+test_geant4__fatras_particles_initial.root: 077546f5598fbf32ea15dc1b2a4741c7bfe51d6d3b96421ff04b999aaf21c2fd
+test_geant4__hits.root: 507461900225433b2452c66db9a9712bfe431f157bff9f98115b30d2b0ac361e
 test_seeding__estimatedparams.root: 3d181aeda75f4a030ab015c90291c21448c61e513ad1e7bfcaf56317b7af1a68
 test_seeding__performance_seeding_trees.root: b53253e5549c09282d68cf11716ff53fa68ea340e25277571b4bc52d43804469
 test_seeding__particles.root: 8c22c826bf7b46de59f479b00e1aa54871570ba85a09d0b221527499f84c4be3