feat!: link dRICH PID with Reconstructed*ChargedParticles

docs/design/gaudi-algorithms.md

@@ -258,10 +258,10 @@ flowchart LR
     HcalEndcapPClusters(HcalEndcapPClusters<br/>HcalEndcapPClustersAssoc)
   end
 
-  MCParticles --> ParticlesWithTruthPID[ParticlesWithTruthPID]:::alg
-  outputTrackParameters --> ParticlesWithTruthPID
-  ParticlesWithTruthPID --> ReconstructedChargedParticles(ReconstructedChargedParticles)
-  ParticlesWithTruthPID --> ReconstructedChargedParticlesAssoc(ReconstructedChargedParticlesAssoc)
+  MCParticles --> ParticlesWithPID[ParticlesWithPID]:::alg
+  outputTrackParameters --> ParticlesWithPID
+  ParticlesWithPID --> ReconstructedChargedParticles(ReconstructedChargedParticles)
+  ParticlesWithPID --> ReconstructedChargedParticlesAssoc(ReconstructedChargedParticlesAssoc)
 
   MCParticles --> MatchClusters[MatchClusters]:::alg
   ReconstructedChargedParticles --> MatchClusters

docs/design/particle_matching.md

@@ -25,11 +25,11 @@ flowchart LR
   MCParticles --> MC2SmearedParticle[MC2SmearedParticle]:::alg
   MC2SmearedParticle --> GeneratedParticles
 
-  MCParticles --> ParticlesWithTruthPID[ParticlesWithTruthPID]:::alg
-  TrackingOutput --> ParticlesWithTruthPID
+  MCParticles --> ParticlesWithPID[ParticlesWithPID]:::alg
+  TrackingOutput --> ParticlesWithPID
 
-  ParticlesWithTruthPID --> ReconstructedChargedParticles(ReconstructedChargedParticles)
-  ParticlesWithTruthPID --> ReconstructedChargedParticlesAssoc(ReconstructedChargedParticlesAssoc)
+  ParticlesWithPID --> ReconstructedChargedParticles(ReconstructedChargedParticles)
+  ParticlesWithPID --> ReconstructedChargedParticlesAssoc(ReconstructedChargedParticlesAssoc)
 
   MCParticles --> MatchClusters[MatchClusters]:::alg
   ReconstructedChargedParticles --> MatchClusters

docs/design/tracking.md

@@ -22,12 +22,12 @@ flowchart TB
 
   ACTSToModel --> TrackingModel(Tracking PODIO data)
 
-  TrackingModel --> ParticlesWithTruthPID:::alg
-  MCParticles --> ParticlesWithTruthPID[<strong>Track to MC matching</strong>:<br/><i>ParticlesWithTruthPID</i>]
+  TrackingModel --> ParticlesWithPID:::alg
+  MCParticles --> ParticlesWithPID[<strong>Track to MC matching</strong>:<br/><i>ParticlesWithPID</i>]
   ACTSToModel --> CentralTrackSegments
 
-  ParticlesWithTruthPID --> ReconstructedChargedParticles
-  ParticlesWithTruthPID --> ReconstructedChargedParticlesAssociations
+  ParticlesWithPID --> ReconstructedChargedParticles
+  ParticlesWithPID --> ReconstructedChargedParticlesAssociations
 
   subgraph Tracking output
     direction LR
@@ -132,10 +132,10 @@ flowchart TB
       CentralCKFTrajectories --> TrackProjector[TrackProjector]:::alg
   TrackProjector --> CentralTrackSegments
 
-  outputTrackParameters --> ParticlesWithTruthPID[ParticlesWithTruthPID]:::alg
-  MCParticles --> ParticlesWithTruthPID
-  ParticlesWithTruthPID --> ReconstructedChargedParticles
-  ParticlesWithTruthPID --> ReconstructedChargedParticlesAssociations
+  outputTrackParameters --> ParticlesWithPID[ParticlesWithPID]:::alg
+  MCParticles --> ParticlesWithPID
+  ParticlesWithPID --> ReconstructedChargedParticles
+  ParticlesWithPID --> ReconstructedChargedParticlesAssociations
 
 
 
@@ -165,5 +165,5 @@ The flow is:
 - Reconstructed hits from all detectors get to **TrackerSourceLinker** which provides measurement and linkage data for ACTS
 - **CFKTracking** does fitting and produces results in ACTS classes
 - **ParticlesFromTrackFit** process ACTS data and store it to PODIO edm4hep/eic data model
-- **ParticlesWithTruthPID** algorithm does track-matching with MCParticles and produce resulted `edm4eic::ReconstructedParticles` with association class
+- **ParticlesWithPID** algorithm does track-matching with MCParticles and produce resulted `edm4eic::ReconstructedParticles` with association class
 - **TrackProjection** - saves track states/points data to PODIO data model and returns CetntralTrackSegments data

src/algorithms/pid/ConvertParticleID.h

@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright (C) 2023, Christopher Dilks
+
+// Converters of ParticleID objects
+//
+
+#pragma once
+
+#include <cstddef>
+#include <map>
+
+// data model
+#include <edm4eic/CherenkovParticleID.h>
+#include <edm4eic/CherenkovParticleIDHypothesis.h>
+#include <edm4hep/ParticleIDCollection.h>
+
+namespace eicrecon {
+
+  class ConvertParticleID {
+    public:
+
+      // index map, used for external access to the converted objects
+      using IndexMap = std::map<std::size_t, unsigned int>; // <collection index, object ID>
+
+      // convert edm4eic::CherenkovParticleID hypotheses to list of edm4hep::ParticleID objects
+      // - requires input `CherenkovParticleID` object `in_pid`
+      // - adds output `ParticleID` objects to collection `out_pids`
+      // - sorted by likelihood, if `sort_by_likelihood==true`
+      // - returns a map of the new `out_pid` indices to new `ParticleID` IDs, so the caller can
+      //   access the newly created `ParticleID` objects
+      static IndexMap ConvertToParticleIDs(
+          const edm4eic::CherenkovParticleID& in_pid,
+          edm4hep::ParticleIDCollection&      out_pids,
+          bool                                sort_by_likelihood = false
+          )
+      {
+
+        // output vector of collection indices
+        IndexMap out_indices;
+
+        // build list of (hypothesis index, hypothesis weight)
+        using HypIndex = std::pair<std::size_t, decltype(edm4eic::CherenkovParticleIDHypothesis::weight)>;
+        std::vector<HypIndex> hyp_indices;
+        for(std::size_t hyp_index=0; hyp_index<in_pid.hypotheses_size(); hyp_index++)
+          hyp_indices.push_back(HypIndex{
+              hyp_index,
+              in_pid.getHypotheses(hyp_index).weight
+              });
+
+        // sort it by likelihood, if needed
+        if(sort_by_likelihood)
+          std::sort(
+              hyp_indices.begin(),
+              hyp_indices.end(),
+              [] (HypIndex& a, HypIndex& b) { return a.second > b.second; }
+              );
+
+        // create and fill output objects
+        for(const auto& [hyp_index, hyp_weight] : hyp_indices) {
+
+          // get the input hypothesis
+          auto in_hyp = in_pid.getHypotheses(hyp_index);
+
+          // create output `ParticleID` object
+          auto out_index = out_pids.size();
+          auto out_pid   = out_pids.create();
+          out_indices.insert({out_index, out_pid.id()});
+
+          // fill scalars
+          out_pid.setPDG(           static_cast<decltype(edm4hep::ParticleIDData::PDG)>           (in_hyp.PDG)    );
+          out_pid.setLikelihood(    static_cast<decltype(edm4hep::ParticleIDData::likelihood)>    (in_hyp.weight) );
+          out_pid.setType(          static_cast<decltype(edm4hep::ParticleIDData::type)>          (0)             ); // FIXME: not used yet
+          out_pid.setAlgorithmType( static_cast<decltype(edm4hep::ParticleIDData::algorithmType)> (0)             ); // FIXME: not used yet
+
+          // fill parameters vector
+          out_pid.addToParameters( static_cast<float> (in_hyp.npe) ); // NPE for this hypothesis
+
+        }
+
+        return out_indices;
+      }
+
+  }; // class ConvertParticleID
+} // namespace eicrecon