GlobalTrajectoryBuilderBase.cc

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#include "RecoMuon/GlobalTrackingTools/interface/GlobalTrajectoryBuilderBase.h"

//---------------
// C++ Headers --
//---------------

#include <iostream>
#include <algorithm>
#include <limits>

//-------------------------------
// Collaborating Class Headers --
//-------------------------------

#include "FWCore/Framework/interface/Event.h"
#include "FWCore/ParameterSet/interface/ParameterSet.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"

#include "CommonTools/Statistics/interface/ChiSquaredProbability.h"
#include "TrackingTools/TrackFitters/interface/RecHitLessByDet.h"
#include "TrackingTools/PatternTools/interface/TrajectoryMeasurement.h"
#include "TrackingTools/TrajectoryState/interface/TrajectoryStateTransform.h"

#include "DataFormats/Math/interface/deltaR.h"

#include "DataFormats/DetId/interface/DetId.h"
#include "DataFormats/MuonDetId/interface/DTChamberId.h"
#include "DataFormats/MuonDetId/interface/CSCDetId.h"
#include "DataFormats/MuonDetId/interface/RPCDetId.h"

#include "DataFormats/TrackReco/interface/Track.h"
#include "DataFormats/TrackReco/interface/TrackExtraFwd.h"
#include "DataFormats/TrackerCommon/interface/TrackerTopology.h"
#include "Geometry/Records/interface/TrackerTopologyRcd.h"

#include "RecoMuon/GlobalTrackingTools/interface/GlobalMuonTrackMatcher.h"
#include "RecoMuon/GlobalTrackingTools/interface/GlobalMuonRefitter.h"
#include "RecoMuon/TransientTrackingRecHit/interface/MuonTransientTrackingRecHitBuilder.h"
#include "RecoMuon/TransientTrackingRecHit/interface/MuonTransientTrackingRecHit.h"
#include "RecoMuon/TrackingTools/interface/MuonCandidate.h"
#include "RecoMuon/TrackingTools/interface/MuonServiceProxy.h"

#include "RecoMuon/GlobalTrackingTools/interface/MuonTrackingRegionBuilder.h"
#include "TrackingTools/Records/interface/TrackingComponentsRecord.h"
#include "TrackingTools/Records/interface/TransientRecHitRecord.h"
#include "TrackingTools/TransientTrack/interface/TransientTrack.h"

#include "RecoTracker/TkTrackingRegions/interface/TkTrackingRegionsMargin.h"
#include "RecoTracker/TkMSParametrization/interface/PixelRecoRange.h"

#include "DataFormats/TrackerRecHit2D/interface/SiStripRecHit2D.h"
#include "Geometry/CommonTopologies/interface/StripTopology.h"

//----------------
// Constructors --
//----------------
GlobalTrajectoryBuilderBase::GlobalTrajectoryBuilderBase(const edm::ParameterSet& par,
                                                         const MuonServiceProxy* service,
                             edm::ConsumesCollector& iC) : 
  theLayerMeasurements(nullptr),theTrackTransformer(nullptr),theRegionBuilder(nullptr), theService(service),theGlbRefitter(nullptr) {

  theCategory = par.getUntrackedParameter<std::string>("Category", "Muon|RecoMuon|GlobalMuon|GlobalTrajectoryBuilderBase");

  
  edm::ParameterSet trackMatcherPSet = par.getParameter<edm::ParameterSet>("GlobalMuonTrackMatcher");
  theTrackMatcher = new GlobalMuonTrackMatcher(trackMatcherPSet,theService);
  
  theTrackerPropagatorName = par.getParameter<std::string>("TrackerPropagator");

  edm::ParameterSet trackTransformerPSet = par.getParameter<edm::ParameterSet>("TrackTransformer");
  theTrackTransformer = new TrackTransformer(trackTransformerPSet);

  edm::ParameterSet regionBuilderPSet = par.getParameter<edm::ParameterSet>("MuonTrackingRegionBuilder");

  theRegionBuilder = new MuonTrackingRegionBuilder(regionBuilderPSet,iC);

  // TrackRefitter parameters
  edm::ParameterSet refitterParameters = par.getParameter<edm::ParameterSet>("GlbRefitterParameters");
  theGlbRefitter = new GlobalMuonRefitter(refitterParameters, theService, iC);

  theMuonHitsOption = refitterParameters.getParameter<int>("MuonHitsOption");
  theRefitFlag = refitterParameters.getParameter<bool>("RefitFlag");

  theTrackerRecHitBuilderName = par.getParameter<std::string>("TrackerRecHitBuilder");
  theMuonRecHitBuilderName = par.getParameter<std::string>("MuonRecHitBuilder");

  theRPCInTheFit = par.getParameter<bool>("RefitRPCHits");

  theTECxScale = par.getParameter<double>("ScaleTECxFactor");
  theTECyScale = par.getParameter<double>("ScaleTECyFactor");
  thePtCut = par.getParameter<double>("PtCut");
  thePCut = par.getParameter<double>("PCut");

  theCacheId_TRH = 0;

}


//--------------
// Destructor --
//--------------
GlobalTrajectoryBuilderBase::~GlobalTrajectoryBuilderBase() {

  if (theTrackMatcher) delete theTrackMatcher;
  if (theRegionBuilder) delete theRegionBuilder;
  if (theTrackTransformer) delete theTrackTransformer;
  if (theGlbRefitter) delete theGlbRefitter;
}


//
// set Event
//
void GlobalTrajectoryBuilderBase::setEvent(const edm::Event& event) {
  
  theEvent = &event;

  theTrackTransformer->setServices(theService->eventSetup());
  theRegionBuilder->setEvent(event);

  theGlbRefitter->setEvent(event);
  theGlbRefitter->setServices(theService->eventSetup());

  unsigned long long newCacheId_TRH = theService->eventSetup().get<TransientRecHitRecord>().cacheIdentifier();
  if ( newCacheId_TRH != theCacheId_TRH ) {
    LogDebug(theCategory) << "TransientRecHitRecord changed!";
    theCacheId_TRH = newCacheId_TRH;
    theService->eventSetup().get<TransientRecHitRecord>().get(theTrackerRecHitBuilderName,theTrackerRecHitBuilder);
    theService->eventSetup().get<TransientRecHitRecord>().get(theMuonRecHitBuilderName,theMuonRecHitBuilder);
  }

  //Retrieve tracker topology from geometry
  edm::ESHandle<TrackerTopology> tTopoHand;
  theService->eventSetup().get<TrackerTopologyRcd>().get(tTopoHand);
  theTopo=tTopoHand.product();

}


//
// build a combined tracker-muon trajectory
//
MuonCandidate::CandidateContainer 
GlobalTrajectoryBuilderBase::build(const TrackCand& staCand,
                                   MuonCandidate::CandidateContainer& tkTrajs ) const {

  LogTrace(theCategory) << " Begin Build" << std::endl;

  // tracker trajectory should be built and refit before this point
  if ( tkTrajs.empty() ) return CandidateContainer();

  // add muon hits and refit/smooth trajectories
  CandidateContainer refittedResult;
  ConstRecHitContainer muonRecHits = getTransientRecHits(*(staCand.second));

  // check order of muon measurements
  if ( (muonRecHits.size() > 1) &&
       ( muonRecHits.front()->globalPosition().mag() >
     muonRecHits.back()->globalPosition().mag() ) ) {
    LogTrace(theCategory)<< "   reverse order: ";
  }

  for (auto&& it: tkTrajs){
    // cut on tracks with low momenta
    LogTrace(theCategory)<< "   Track p and pT " << it->trackerTrack()->p() << " " << it->trackerTrack()->pt();
    if(  it->trackerTrack()->p() < thePCut || it->trackerTrack()->pt() < thePtCut  ) continue;

    // If true we will run theGlbRefitter->refit from all hits
    if (theRefitFlag){
        ConstRecHitContainer trackerRecHits;
        if (it->trackerTrack().isNonnull()) {
          trackerRecHits = getTransientRecHits(*it->trackerTrack());
        } else {
          LogDebug(theCategory)<<"     NEED HITS FROM TRAJ";
        }
    
        // ToDo: Do we need the following ?:
        // check for single TEC RecHits in trajectories in the overalp region
        if ( std::abs(it->trackerTrack()->eta()) > 0.95 && std::abs(it->trackerTrack()->eta()) < 1.15 && it->trackerTrack()->pt() < 60 ) {
          if ( theTECxScale < 0 || theTECyScale < 0 )
            trackerRecHits = selectTrackerHits(trackerRecHits);
          else
            fixTEC(trackerRecHits,theTECxScale,theTECyScale);
        }
              
        RefitDirection recHitDir = checkRecHitsOrdering(trackerRecHits);
        if ( recHitDir == outToIn ) reverse(trackerRecHits.begin(),trackerRecHits.end());
    
        reco::TransientTrack tTT(it->trackerTrack(),&*theService->magneticField(),theService->trackingGeometry());
        TrajectoryStateOnSurface innerTsos = tTT.innermostMeasurementState();
    
        edm::RefToBase<TrajectorySeed> tmpSeed;
        if(it->trackerTrack()->seedRef().isAvailable()) tmpSeed = it->trackerTrack()->seedRef();
    
        if ( !innerTsos.isValid() ) {
          LogTrace(theCategory) << "     inner Trajectory State is invalid. ";
          continue;
        }
      
        innerTsos.rescaleError(100.);
                      
        TC refitted0,refitted1;
        MuonCandidate* finalTrajectory = nullptr;
        Trajectory *tkTrajectory = nullptr;
    
        // tracker only track
        if ( ! (it->trackerTrajectory() && it->trackerTrajectory()->isValid()) ) {
          refitted0 = theTrackTransformer->transform(it->trackerTrack()) ;
          if (!refitted0.empty()) tkTrajectory = new Trajectory(*(refitted0.begin())); 
          else edm::LogWarning(theCategory)<< "     Failed to load tracker track trajectory";
        } else tkTrajectory = it->trackerTrajectory();
        if (tkTrajectory) tkTrajectory->setSeedRef(tmpSeed);
    
        // full track with all muon hits using theGlbRefitter    
        ConstRecHitContainer allRecHits = trackerRecHits;
        allRecHits.insert(allRecHits.end(), muonRecHits.begin(),muonRecHits.end());
        refitted1 = theGlbRefitter->refit( *it->trackerTrack(), tTT, allRecHits,theMuonHitsOption, theTopo);
        LogTrace(theCategory)<<"     This track-sta refitted to " << refitted1.size() << " trajectories";
    
        Trajectory *glbTrajectory1 = nullptr;
        if (!refitted1.empty()) glbTrajectory1 = new Trajectory(*(refitted1.begin()));
        else LogDebug(theCategory)<< "     Failed to load global track trajectory 1"; 
        if (glbTrajectory1) glbTrajectory1->setSeedRef(tmpSeed);
        
        finalTrajectory = nullptr;
        if(glbTrajectory1 && tkTrajectory) finalTrajectory = new MuonCandidate(glbTrajectory1, it->muonTrack(), it->trackerTrack(),
                        tkTrajectory? new Trajectory(*tkTrajectory) : nullptr);
    
        if ( finalTrajectory ) refittedResult.push_back(finalTrajectory);
        if(tkTrajectory) delete tkTrajectory;
      }
      else{
        MuonCandidate* finalTrajectory = nullptr;
        edm::RefToBase<TrajectorySeed> tmpSeed;
        if(it->trackerTrack()->seedRef().isAvailable()) tmpSeed = it->trackerTrack()->seedRef();
    
        TC refitted0;
        Trajectory *tkTrajectory = nullptr;
        if ( ! (it->trackerTrajectory() && it->trackerTrajectory()->isValid()) ) {
          refitted0 = theTrackTransformer->transform(it->trackerTrack());
          if (!refitted0.empty()){
              tkTrajectory = new Trajectory(*(refitted0.begin()));
          }
          else edm::LogWarning(theCategory)<< "     Failed to load tracker track trajectory";
        }
        else tkTrajectory = it->trackerTrajectory();
        if (tkTrajectory) tkTrajectory->setSeedRef(tmpSeed);
        // Creating MuonCandidate using only the tracker trajectory:
        finalTrajectory = new MuonCandidate(new Trajectory(*tkTrajectory), it->muonTrack(), it->trackerTrack(),new Trajectory(*tkTrajectory));
        if (finalTrajectory) refittedResult.push_back(finalTrajectory);
        if(tkTrajectory) delete tkTrajectory;
      }
  }

  // choose the best global fit for this Standalone Muon based on the track probability
  CandidateContainer selectedResult;
  MuonCandidate* tmpCand = nullptr;
  if ( !refittedResult.empty() ) tmpCand = *(refittedResult.begin());
  double minProb = std::numeric_limits<double>::max();

  for (auto&& iter: refittedResult){
    double prob = trackProbability(*iter->trajectory());
    LogTrace(theCategory)<<"   refitted-track-sta with pT " << iter->trackerTrack()->pt() << " has probability " << prob;

    if (prob < minProb) {
      minProb = prob;
      tmpCand = iter;
    }
  }

  if ( tmpCand )  selectedResult.push_back(new MuonCandidate(new Trajectory(*(tmpCand->trajectory())), tmpCand->muonTrack(), tmpCand->trackerTrack(), 
                                 (tmpCand->trackerTrajectory())? new Trajectory( *(tmpCand->trackerTrajectory()) ):nullptr ) );

  for (auto&& it: refittedResult){
    if ( it->trajectory() ) delete it->trajectory();
    if ( it->trackerTrajectory() ) delete it->trackerTrajectory();
    if ( it ) delete it;
  }
  refittedResult.clear();

  return selectedResult;

}


//
// select tracker tracks within a region of interest
//
std::vector<GlobalTrajectoryBuilderBase::TrackCand>
GlobalTrajectoryBuilderBase::chooseRegionalTrackerTracks(const TrackCand& staCand, 
                                                         const std::vector<TrackCand>& tkTs) {
  
  // define eta-phi region
  RectangularEtaPhiTrackingRegion regionOfInterest = defineRegionOfInterest(staCand.second);
  
  // get region's etaRange and phiMargin
  //UNUSED:  PixelRecoRange<float> etaRange = regionOfInterest.etaRange();
  //UNUSED:  TkTrackingRegionsMargin<float> phiMargin = regionOfInterest.phiMargin();

  std::vector<TrackCand> result;

  double deltaR_max = 1.0;

  for (auto&& is: tkTs){
    double deltaR_tmp = deltaR(static_cast<double>(regionOfInterest.direction().eta()),
                               static_cast<double>(regionOfInterest.direction().phi()),
                               is.second->eta(), is.second->phi());

    // for each trackCand in region, add trajectory and add to result
    //if ( inEtaRange && inPhiRange ) {
    if (deltaR_tmp < deltaR_max) {
      TrackCand tmpCand = TrackCand(is);
      result.push_back(tmpCand);
    }
  }

  return result; 

}


//
// define a region of interest within the tracker
//
RectangularEtaPhiTrackingRegion 
GlobalTrajectoryBuilderBase::defineRegionOfInterest(const reco::TrackRef& staTrack) const {

  std::unique_ptr<RectangularEtaPhiTrackingRegion> region1 = theRegionBuilder->region(staTrack);
  
  TkTrackingRegionsMargin<float> etaMargin(std::abs(region1->etaRange().min() - region1->etaRange().mean()),
                       std::abs(region1->etaRange().max() - region1->etaRange().mean()));
  
  RectangularEtaPhiTrackingRegion region2(region1->direction(),
                      region1->origin(),
                      region1->ptMin(),
                      region1->originRBound(),
                      region1->originZBound(),
                      etaMargin,
                      region1->phiMargin());
  
  return region2;
  
}


//
// calculate the tail probability (-ln(P)) of a fit
//
double 
GlobalTrajectoryBuilderBase::trackProbability(const Trajectory& track) const {

  if ( track.ndof() > 0 && track.chiSquared() > 0 ) { 
    return -LnChiSquaredProbability(track.chiSquared(), track.ndof());
  } else {
    return 0.0;
  }

}


//
// print RecHits
//
void GlobalTrajectoryBuilderBase::printHits(const ConstRecHitContainer& hits) const {

  LogTrace(theCategory) << "Used RecHits: " << hits.size();
  for (auto&& ir: hits){
    if ( !ir->isValid() ) {
      LogTrace(theCategory) << "invalid RecHit";
      continue; 
    }
    
    const GlobalPoint& pos = ir->globalPosition();
    
    LogTrace(theCategory) 
      << "r = " << sqrt(pos.x() * pos.x() + pos.y() * pos.y())
      << "  z = " << pos.z()
      << "  dimension = " << ir->dimension()
      << "  " << ir->det()->geographicalId().det()
      << "  " << ir->det()->subDetector();

  }

}

//
// check order of RechIts on a trajectory
//
GlobalTrajectoryBuilderBase::RefitDirection
GlobalTrajectoryBuilderBase::checkRecHitsOrdering(const TransientTrackingRecHit::ConstRecHitContainer& recHits) const {

  if ( !recHits.empty() ) {
    ConstRecHitContainer::const_iterator frontHit = recHits.begin();
    ConstRecHitContainer::const_iterator backHit  = recHits.end() - 1;
    while ( !(*frontHit)->isValid() && frontHit != backHit ) {frontHit++;}
    while ( !(*backHit)->isValid() && backHit != frontHit )  {backHit--;}

    double rFirst = (*frontHit)->globalPosition().mag();
    double rLast  = (*backHit) ->globalPosition().mag();

    if ( rFirst < rLast ) return inToOut;
    else if (rFirst > rLast) return outToIn;
    else {
      edm::LogError(theCategory) << "Impossible to determine the rechits order" << std::endl;
      return undetermined;
    }
  }
  else {
    edm::LogError(theCategory) << "Impossible to determine the rechits order" << std::endl;
    return undetermined;
  }
}


//
// select trajectories with only a single TEC hit
//
GlobalTrajectoryBuilderBase::ConstRecHitContainer 
GlobalTrajectoryBuilderBase::selectTrackerHits(const ConstRecHitContainer& all) const {
 
  int nTEC(0);

  ConstRecHitContainer hits;
  for (auto&& i: all){
    if ( !i->isValid() ) continue;
    if ( i->det()->geographicalId().det() == DetId::Tracker &&
         i->det()->geographicalId().subdetId() == StripSubdetector::TEC) {
      nTEC++;
    } else {
      hits.push_back(i);
    }
    if ( nTEC > 1 ) return all;
  }

  return hits;

}


//
// rescale errors of outermost TEC RecHit
//
void GlobalTrajectoryBuilderBase::fixTEC(ConstRecHitContainer& all,
                                         double scl_x,
                                         double scl_y) const {

  int nTEC(0);
  ConstRecHitContainer::iterator lone_tec;

  for ( ConstRecHitContainer::iterator i = all.begin(); i != all.end(); i++) {
    if ( !(*i)->isValid() ) continue;
    
    if ( (*i)->det()->geographicalId().det() == DetId::Tracker &&
         (*i)->det()->geographicalId().subdetId() == StripSubdetector::TEC) {
      lone_tec = i;
      nTEC++;
      
      if ( (i+1) != all.end() && (*(i+1))->isValid() &&
          (*(i+1))->det()->geographicalId().det() == DetId::Tracker &&
          (*(i+1))->det()->geographicalId().subdetId() == StripSubdetector::TEC) {
        nTEC++;
        break;
      }
    }
    
    if (nTEC > 1) break;
  }
  
  int hitDet = (*lone_tec)->hit()->geographicalId().det();
  int hitSubDet = (*lone_tec)->hit()->geographicalId().subdetId();
  if ( nTEC == 1 && (*lone_tec)->hit()->isValid() &&
       hitDet == DetId::Tracker && hitSubDet == StripSubdetector::TEC) {
    
    // rescale the TEC rechit error matrix in its rotated frame
    const SiStripRecHit2D* strip = dynamic_cast<const SiStripRecHit2D*>((*lone_tec)->hit());
    if (strip && strip->det() ) {
      LocalPoint pos = strip->localPosition();
      if ((*lone_tec)->detUnit()) {
        const StripTopology* topology = dynamic_cast<const StripTopology*>(&(*lone_tec)->detUnit()->topology());
        if (topology) {
          // rescale the local error along/perp the strip by a factor
          float angle = topology->stripAngle(topology->strip((*lone_tec)->hit()->localPosition()));
          LocalError error = strip->localPositionError();
          LocalError rotError = error.rotate(angle);
          LocalError scaledError(rotError.xx() * scl_x * scl_x, 0, rotError.yy() * scl_y * scl_y);
          error = scaledError.rotate(-angle);
            SiStripRecHit2D* st = new SiStripRecHit2D(pos,error,
                                                      *strip->det(),
                                                      strip->cluster());
            *lone_tec = MuonTransientTrackingRecHit::build((*lone_tec)->det(),st);
 
        }
      }
    }
  }

}


#include "RecoTracker/TransientTrackingRecHit/interface/TkTransientTrackingRecHitBuilder.h"
//
// get transient RecHits
//
TransientTrackingRecHit::ConstRecHitContainer
GlobalTrajectoryBuilderBase::getTransientRecHits(const reco::Track& track) const {

  TransientTrackingRecHit::ConstRecHitContainer result;
  
  

  TrajectoryStateOnSurface currTsos = trajectoryStateTransform::innerStateOnSurface(track, *theService->trackingGeometry(), &*theService->magneticField());

  auto tkbuilder = static_cast<TkTransientTrackingRecHitBuilder const *>(theTrackerRecHitBuilder.product());
  auto hitCloner = tkbuilder->cloner(); 
  for (trackingRecHit_iterator hit = track.recHitsBegin(); hit != track.recHitsEnd(); ++hit) {
    if((*hit)->isValid()) {
      DetId recoid = (*hit)->geographicalId();
      if ( recoid.det() == DetId::Tracker ) {
    if (!(*hit)->hasPositionAndError()){
      TrajectoryStateOnSurface predTsos =  theService->propagator(theTrackerPropagatorName)->propagate(currTsos, theService->trackingGeometry()->idToDet(recoid)->surface());
      
      if ( !predTsos.isValid() ) {
        edm::LogError("MissingTransientHit")
          <<"Could not get a tsos on the hit surface. We will miss a tracking hit.";
        continue; 
      }
      currTsos = predTsos;
          auto h = (**hit).cloneForFit(*tkbuilder->geometry()->idToDet( (**hit).geographicalId() ) );
      result.emplace_back(hitCloner.makeShared(h,predTsos));
    }else{
      result.push_back((*hit)->cloneSH());
    }
      } else if ( recoid.det() == DetId::Muon ) {
    if ( (*hit)->geographicalId().subdetId() == 3 && !theRPCInTheFit) {
      LogDebug(theCategory) << "RPC Rec Hit discarded"; 
      continue;
    }
    result.push_back(theMuonRecHitBuilder->build(&**hit));
      }
    }
  }
  
  return result;
}