Proposal for a Protocluster-Track Match

[ruse-traveler]

Is your feature request related to a problem? Please describe.

It was proposed in discussion to EICrecon#1699 to update the TrackClusterMergeSplitter algorithm so that it consumes clusters, and then outputs protoclusters so that they can be reconstructed by ClusterRecoCoG and consumed by downstream PF algorithms. Since connections between the merged/split clusters and their antecedent tracks are crucial to these downstream algorithms, there will need to be changes to the data model to propagate this information.

Describe the solution you'd like

Part of the proposal by @veprbl in EICrecon#1699 was to add a ProtoClusterTrackMatch type (parallel to edm4eic::ClusterTrackMatch). This type would look something like this:

  edm4eic::TrackProtoClusterMatch:
    Description: "Match between a ProtoCluster and a Track"
    Author: "D. Kalinkin, D. Anderson"
    Members:
      - float weight  // weight of this association
    OneToOneRelations:
      - edm4eic::ProtoCluster protocluster  // reference to the protocluster
      - edm4eic::Track        track         // reference to the track

The type's introduction to the data model would be followed by a PR to EICrecon to add a "promotion" algorithm that would copy the protocluster-track matches to the relevant cluster-track matches after their CoG reconstruction.

Describe alternatives you've considered

An alternative could be to instead deprecate edm4eic::ProtoCluster and use the edm4eic::Cluster in all clustering/reclustering algorithms since the latter is a superset of the former. While this certainly should be considered at some point, this would be less preferable in the near term as it would necessitate updating several algorithms in EICrecon.

Additional context
Add any other context or screenshots about the feature request here.

[veprbl]

No objections in today's meeting, although attendance was relatively thin. I think, we are ready to move to a PR, we can advertise in software news again, in case there is any other feedback.

[ruse-traveler]

Sounds good! I'll open one up tonight or tomorrow...