LinearTruthTracking.h

#pragma once
 
//---< Framework >---//
#include "Framework/Configure/Parameters.h"
#include "Framework/Event.h"
#include "Framework/EventProcessor.h"
 
//---< SimCore >---//
#include "SimCore/Event/SimTrackerHit.h"
 
//---< STD C++ >---//
 
//--- LDMX ---//
#include "Tracking/Event/StraightTrack.h"
#include "Tracking/Reco/TrackingGeometryUser.h"
 
namespace tracking {
namespace reco {
 
class LinearTruthTracking : public TrackingGeometryUser {
 public:
  LinearTruthTracking(const std::string& name, framework::Process& process);
 
  virtual ~LinearTruthTracking() = default;
  void onProcessEnd() override;
  void configure(framework::config::Parameters& parameters) override;
 
  void produce(framework::Event& event) override;
 
 protected:
  // Function to find recoil e- based on 4 recoil points with trackID = 1
  ldmx::StraightTrack truthTracker(
      const std::vector<ldmx::SimTrackerHit>& points,
      std::vector<std::array<double, 3>>& ecal_points);
 
  // Helper function: calculate distance between 2 3D points
  double calculateDistance(const std::array<double, 3>& point1,
                           const std::array<double, 3>& point2);
 
  // Fitting function: fit a straight line in 3D using 4 points (2 degrees of
  // freedom)
  std::tuple<double, double, double, double> fit3DLine(
      const std::vector<ldmx::SimTrackerHit>& points);
 
  // Calculate chi2 of the fit
  double globalChiSquare(const std::vector<ldmx::SimTrackerHit>& points,
                         double a_x, double a_y, double b_x, double b_y);
 
  double processing_time_{0.};
  long n_events_{0};
  unsigned int n_truth_{0};
  long n_missing_{0};
  long n_empty_{0};
 
  // Assuming rLDMX v1 geometry
  double ecal_first_layer_z_threshold_{250.0};
 
  std::string out_trk_collection_{"LinearRecoilTruthTracks"};
  std::string input_hits_collection_{"RecoilSimHits"};
  std::string input_rec_hits_collection_{"EcalRecHits"};
  std::string input_pass_name_{""};
 
};  // LinearTruthTracking
 
}  // namespace reco
}  // namespace tracking