GlobalTrajectoryBuilderBase.cc

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

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

#include <iostream>
#include <algorithm>

//-------------------------------
// 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/TrajectoryStateOnSurface.h"
#include "TrackingTools/TrajectoryState/interface/TrajectoryStateTransform.h"
#include "TrackingTools/TrackRefitter/interface/TrackTransformer.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/SiStripDetId/interface/TECDetId.h"

#include "RecoTracker/TkTrackingRegions/interface/RectangularEtaPhiTrackingRegion.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/TrackFitters/interface/TrajectoryFitter.h"
#include "TrackingTools/TransientTrackingRecHit/interface/TransientTrackingRecHitBuilder.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 "RecoTracker/TransientTrackingRecHit/interface/TSiStripRecHit2DLocalPos.h"
#include "Geometry/CommonTopologies/interface/StripTopology.h"

using namespace std;
using namespace edm;

//----------------
// Constructors --
//----------------
GlobalTrajectoryBuilderBase::GlobalTrajectoryBuilderBase(const edm::ParameterSet& par,
                                                         const MuonServiceProxy* service) : 
  theTrackMatcher(0),theLayerMeasurements(0),theTrackTransformer(0),theRegionBuilder(0), theService(service),theGlbRefitter(0) {

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

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

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

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

  theRegionBuilder = new MuonTrackingRegionBuilder(regionBuilderPSet,theService);

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

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

  theTrackerRecHitBuilderName = par.getParameter<string>("TrackerRecHitBuilder");
  theMuonRecHitBuilderName = par.getParameter<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);
  }

}


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

  LogTrace(theCategory) << " Begin Build" << 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 ( CandidateContainer::const_iterator it = tkTrajs.begin(); it != tkTrajs.end(); it++ ) {

    // 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;

    ConstRecHitContainer trackerRecHits;
    if ((*it)->trackerTrack().isNonnull()) {
      trackerRecHits = getTransientRecHits(*(*it)->trackerTrack());
    } else {
      LogDebug(theCategory)<<"     NEED HITS FROM TRAJ";
      //trackerRecHits = (*it)->trackerTrajectory()->recHits();
    }

    // check for single TEC RecHits in trajectories in the overalp region
    if ( fabs((*it)->trackerTrack()->eta()) > 0.95 && fabs((*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 = 0;
    Trajectory *tkTrajectory = 0;

    // tracker only track
    if ( ! ((*it)->trackerTrajectory() && (*it)->trackerTrajectory()->isValid()) ) { 
      refitted0 = theTrackTransformer->transform((*it)->trackerTrack()) ;
      if (!refitted0.empty()) tkTrajectory = new Trajectory(*(refitted0.begin())); 
      else 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);
    LogTrace(theCategory)<<"     This track-sta refitted to " << refitted1.size() << " trajectories";

    Trajectory *glbTrajectory1 = 0;
    if (!refitted1.empty()) glbTrajectory1 = new Trajectory(*(refitted1.begin()));
    else LogDebug(theCategory)<< "     Failed to load global track trajectory 1"; 
    if (glbTrajectory1) glbTrajectory1->setSeedRef(tmpSeed);
    
    finalTrajectory = 0;
    if(glbTrajectory1 && tkTrajectory) finalTrajectory = new MuonCandidate(glbTrajectory1, (*it)->muonTrack(), (*it)->trackerTrack(), 
                    tkTrajectory? new Trajectory(*tkTrajectory) : 0);

    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 = 0;
  if ( refittedResult.size() > 0 ) tmpCand = *(refittedResult.begin());
  double minProb = 9999;

  for (CandidateContainer::const_iterator iter=refittedResult.begin(); iter != refittedResult.end(); iter++) {
    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()) ):0 ) );

  for (CandidateContainer::const_iterator it = refittedResult.begin(); it != refittedResult.end(); ++it) {
    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
//
vector<GlobalTrajectoryBuilderBase::TrackCand> 
GlobalTrajectoryBuilderBase::chooseRegionalTrackerTracks(const TrackCand& staCand, 
                                                         const 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();

  vector<TrackCand> result;

  double deltaR_max = 1.0;

  for ( vector<TrackCand>::const_iterator is = tkTs.begin(); is != tkTs.end(); ++is ) {
    // check if each trackCand is in region of interest
//    bool inEtaRange = etaRange.inside(is->second->eta());
//    bool inPhiRange = (fabs(Geom::Phi<float>(is->second->phi()) - Geom::Phi<float>(regionOfInterest.direction().phi())) < phiMargin.right() ) ? true : false ;

    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 {

  RectangularEtaPhiTrackingRegion* region1 = theRegionBuilder->region(staTrack);
  
  TkTrackingRegionsMargin<float> etaMargin(fabs(region1->etaRange().min() - region1->etaRange().mean()),
                       fabs(region1->etaRange().max() - region1->etaRange().mean()));
  
  RectangularEtaPhiTrackingRegion region2(region1->direction(),
                      region1->origin(),
                      region1->ptMin(),
                      region1->originRBound(),
                      region1->originZBound(),
                      etaMargin,
                      region1->phiMargin());
  
  delete region1;
  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 (ConstRecHitContainer::const_iterator ir = hits.begin(); ir != hits.end(); ir++ ) {
    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 {
      LogError(theCategory) << "Impossible to determine the rechits order" << endl;
      return undetermined;
    }
  }
  else {
    LogError(theCategory) << "Impossible to determine the rechits order" << 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 (ConstRecHitContainer::const_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) {
      nTEC++;
    } else {
      hits.push_back((*i).get());
    }
    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());
    const TSiStripRecHit2DLocalPos* Tstrip = dynamic_cast<const TSiStripRecHit2DLocalPos*>((*lone_tec).get());
    if (strip && Tstrip->det() && Tstrip) {
      LocalPoint pos = Tstrip->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 = Tstrip->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);
          MuonTransientTrackingRecHit* mtt_rechit;
          if (strip->cluster().isNonnull()) {
            SiStripRecHit2D* st = new SiStripRecHit2D(pos,error,
                                                      (*lone_tec)->geographicalId().rawId(),
                                                      strip->cluster());
            *lone_tec = mtt_rechit->build((*lone_tec)->det(),st);
          }
          else {
            SiStripRecHit2D* st = new SiStripRecHit2D(pos,error,
                                                      (*lone_tec)->geographicalId().rawId(),
                                                      strip->cluster_regional());
            *lone_tec = mtt_rechit->build((*lone_tec)->det(),st);
          }
        }
      }
    }
  }

}


//
// get transient RecHits
//
TransientTrackingRecHit::ConstRecHitContainer
GlobalTrajectoryBuilderBase::getTransientRecHits(const reco::Track& track) const {

  TransientTrackingRecHit::ConstRecHitContainer result;
  
  

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

  for (trackingRecHit_iterator hit = track.recHitsBegin(); hit != track.recHitsEnd(); ++hit) {
    if((*hit)->isValid()) {
      DetId recoid = (*hit)->geographicalId();
      if ( recoid.det() == DetId::Tracker ) {
    TransientTrackingRecHit::RecHitPointer ttrhit = theTrackerRecHitBuilder->build(&**hit);
    if (!ttrhit->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;
      TransientTrackingRecHit::RecHitPointer preciseHit = ttrhit->clone(predTsos);
      result.push_back(preciseHit);
    }else{
      result.push_back(ttrhit);
    }
      } 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;
}