PixelCPEBase.cc

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// Move geomCorrection to the concrete class. d.k. 06/06.
// Change drift direction. d.k. 06/06
// G. Giurgiu (ggiurgiu@pha.jhu.edu), 12/01/06, implemented the function:
// computeAnglesFromDetPosition(const SiPixelCluster & cl,
// change to use Lorentz angle from DB Lotte Wilke, Jan. 31st, 2008
// Change to use Generic error & Template calibration from DB - D.Fehling 11/08

#include "Geometry/CommonDetUnit/interface/PixelGeomDetUnit.h"
#include "RecoLocalTracker/SiPixelRecHits/interface/PixelCPEBase.h"

#define CORRECT_FOR_BIG_PIXELS

// MessageLogger
#include "FWCore/MessageLogger/interface/MessageLogger.h"

// Magnetic field
#include "MagneticField/Engine/interface/MagneticField.h"

#include <iostream>

using namespace std;

//-----------------------------------------------------------------------------
//  A constructor run for generic and templates
//
//-----------------------------------------------------------------------------
PixelCPEBase::PixelCPEBase(edm::ParameterSet const& conf,
                           const MagneticField* mag,
                           const TrackerGeometry& geom,
                           const TrackerTopology& ttopo,
                           const SiPixelLorentzAngle* lorentzAngle,
                           const SiPixelGenErrorDBObject* genErrorDBObject,
                           const SiPixelTemplateDBObject* templateDBobject,
                           const SiPixelLorentzAngle* lorentzAngleWidth,
                           int flag)
    //  : useLAAlignmentOffsets_(false), useLAOffsetFromConfig_(false),
    : useLAOffsetFromConfig_(false),
      useLAWidthFromConfig_(false),
      useLAWidthFromDB_(false),
      theFlag_(flag),
      magfield_(mag),
      geom_(geom),
      ttopo_(ttopo) {
#ifdef EDM_ML_DEBUG
  nRecHitsTotal_ = 0;
  nRecHitsUsedEdge_ = 0,
#endif

  //--- Lorentz angle tangent per Tesla
      lorentzAngle_ = lorentzAngle;
  lorentzAngleWidth_ = lorentzAngleWidth;

  //-- GenError Calibration Object from DB
  genErrorDBObject_ = genErrorDBObject;

  //-- Template Calibration Object from DB
  if (theFlag_ != 0)
    templateDBobject_ = templateDBobject;  // flag to check if it is generic or templates

  // Configurables
  // For both templates & generic

  // Read templates and/or generic errors from DB
  LoadTemplatesFromDB_ = conf.getParameter<bool>("LoadTemplatesFromDB");

  //--- Algorithm's verbosity
  theVerboseLevel = conf.getUntrackedParameter<int>("VerboseLevel", 0);

  //-- Switch on/off E.B
  alpha2Order = conf.getParameter<bool>("Alpha2Order");

  //--- A flag that could be used to change the behavior of
  //--- clusterProbability() in TSiPixelRecHit (the *transient* one).
  //--- The problem is that the transient hits are made after the CPE runs
  //--- and they don't get the access to the PSet, so we pass it via the
  //--- CPE itself...
  //
  clusterProbComputationFlag_ = (unsigned int)conf.getParameter<int>("ClusterProbComputationFlag");

  // This LA related parameters are only relevant for the Generic algo
  // They still have to be used in Base since the LA computation is in Base

  // Use LA-width from DB.
  // If both (this and from config) are false LA-width is calcuated from LA-offset
  useLAWidthFromDB_ = conf.getParameter<bool>("useLAWidthFromDB");

  // Use Alignment LA-offset in generic
  // (Experimental; leave commented out)
  //useLAAlignmentOffsets_ = conf.existsAs<bool>("useLAAlignmentOffsets")?
  //conf.getParameter<bool>("useLAAlignmentOffsets"):false;

  // Used only for testing
  lAOffset_ = conf.getParameter<double>("lAOffset");
  lAWidthBPix_ = conf.getParameter<double>("lAWidthBPix");
  lAWidthFPix_ = conf.getParameter<double>("lAWidthFPix");

  // Use LA-offset from config, for testing only
  if (lAOffset_ > 0.0)
    useLAOffsetFromConfig_ = true;
  // Use LA-width from config, split into fpix & bpix, for testing only
  if (lAWidthBPix_ > 0.0 || lAWidthFPix_ > 0.0)
    useLAWidthFromConfig_ = true;

  // For Templates only
  // Compute the Lorentz shifts for this detector element for templates (from Alignment)
  doLorentzFromAlignment_ = conf.getParameter<bool>("doLorentzFromAlignment");
  useLAFromDB_ = conf.getParameter<bool>("useLAFromDB");

  LogDebug("PixelCPEBase") << " LA constants - " << lAOffset_ << " " << lAWidthBPix_ << " " << lAWidthFPix_
                           << endl;  //dk

  fillDetParams();
}

//-----------------------------------------------------------------------------
//  Fill all variables which are constant for an event (geometry)
//-----------------------------------------------------------------------------
void PixelCPEBase::fillDetParams() {
  // MM: this code finds the last Pixel (Inner Tracker) DetUnit to loop upon when filling the det params, by looking the first detId which is from
  // the Outer Tracker (Strips in case of the Phase-0/1 detector).

  auto const& dus = geom_.detUnits();
  unsigned m_detectors = dus.size();
  for (unsigned int i = 1; i < 7; ++i) {
    LogDebug("PixelCPEBase:: LookingForFirstStrip")
        << "Subdetector " << i << " GeomDetEnumerator " << GeomDetEnumerators::tkDetEnum[i] << " offset "
        << geom_.offsetDU(GeomDetEnumerators::tkDetEnum[i]) << " is it strip? "
        << (geom_.offsetDU(GeomDetEnumerators::tkDetEnum[i]) != dus.size()
                ? dus[geom_.offsetDU(GeomDetEnumerators::tkDetEnum[i])]->type().isOuterTracker()
                : false);

    if (geom_.offsetDU(GeomDetEnumerators::tkDetEnum[i]) != dus.size() &&
        dus[geom_.offsetDU(GeomDetEnumerators::tkDetEnum[i])]->type().isOuterTracker()) {
      if (geom_.offsetDU(GeomDetEnumerators::tkDetEnum[i]) < m_detectors) {
        m_detectors = geom_.offsetDU(GeomDetEnumerators::tkDetEnum[i]);
      }
    }
  }
  LogDebug("LookingForFirstStrip") << " Chosen offset: " << m_detectors;

  m_DetParams.resize(m_detectors);
  LogDebug("PixelCPEBase::fillDetParams():") << "caching " << m_detectors << " pixel detectors" << endl;
  for (unsigned i = 0; i != m_detectors; ++i) {
    auto& p = m_DetParams[i];
    p.theDet = dynamic_cast<const PixelGeomDetUnit*>(dus[i]);
    assert(p.theDet);
    assert(p.theDet->index() == int(i));

    p.theOrigin = p.theDet->surface().toLocal(GlobalPoint(0, 0, 0));

    //--- p.theDet->type() returns a GeomDetType, which implements subDetector()
    p.thePart = p.theDet->type().subDetector();

    //--- The location in of this DetUnit in a cyllindrical coord system (R,Z)
    //--- The call goes via BoundSurface, returned by p.theDet->surface(), but
    //--- position() is implemented in GloballyPositioned<> template
    //--- ( BoundSurface : Surface : GloballyPositioned<float> )
    //p.theDetR = p.theDet->surface().position().perp();  //Not used, AH
    //p.theDetZ = p.theDet->surface().position().z();  //Not used, AH
    //--- Define parameters for chargewidth calculation

    //--- bounds() is implemented in BoundSurface itself.
    p.theThickness = p.theDet->surface().bounds().thickness();

    // Cache the det id for templates and generic erros

    if (theFlag_ == 0) {         // for generic
      if (LoadTemplatesFromDB_)  // do only if genError requested
        p.detTemplateId = genErrorDBObject_->getGenErrorID(p.theDet->geographicalId().rawId());
    } else {  // for templates
      p.detTemplateId = templateDBobject_->getTemplateID(p.theDet->geographicalId());
    }

    auto topol = &(p.theDet->specificTopology());
    p.theTopol = topol;

    //--- The geometrical description of one module/plaquette
    std::pair<float, float> pitchxy = p.theTopol->pitch();
    p.thePitchX = pitchxy.first;   // pitch along x
    p.thePitchY = pitchxy.second;  // pitch along y

    LocalVector Bfield = p.theDet->surface().toLocal(magfield_->inTesla(p.theDet->surface().position()));
    p.bz = Bfield.z();
    p.bx = Bfield.x();

    //---  Compute the Lorentz shifts for this detector element
    if ((theFlag_ == 0) || useLAFromDB_ ||
        doLorentzFromAlignment_) {  // do always for generic and if using LA from DB or alignment for templates
      p.driftDirection = driftDirection(p, Bfield);
      computeLorentzShifts(p);
    }

    LogDebug("PixelCPEBase::fillDetParams()") << "***** PIXEL LAYOUT *****"
                                              << " thePart = " << p.thePart << " theThickness = " << p.theThickness
                                              << " thePitchX  = " << p.thePitchX << " thePitchY  = " << p.thePitchY;
    //               << " theLShiftX  = " << p.theLShiftX;
  }
}

//-----------------------------------------------------------------------------
//  One function to cache the variables common for one DetUnit.
//-----------------------------------------------------------------------------
void PixelCPEBase::setTheClu(DetParam const& theDetParam, ClusterParam& theClusterParam) const {
  //--- Geometric Quality Information
  int minInX, minInY, maxInX, maxInY = 0;
  minInX = theClusterParam.theCluster->minPixelRow();
  minInY = theClusterParam.theCluster->minPixelCol();
  maxInX = theClusterParam.theCluster->maxPixelRow();
  maxInY = theClusterParam.theCluster->maxPixelCol();

  int min_row(0), min_col(0);
  int max_row = theDetParam.theTopol->nrows() - 1;
  int max_col = theDetParam.theTopol->ncolumns() - 1;

  if (minInX == min_row)
    theClusterParam.edgeTypeX_ = 1;
  else if (maxInX == max_row)
    theClusterParam.edgeTypeX_ = 2;
  else
    theClusterParam.edgeTypeX_ = 0;

  if (minInY == min_col)
    theClusterParam.edgeTypeY_ = 1;
  else if (maxInY == max_col)
    theClusterParam.edgeTypeY_ = 2;
  else
    theClusterParam.edgeTypeY_ = 0;

  theClusterParam.isOnEdge_ = (theClusterParam.edgeTypeX_ || theClusterParam.edgeTypeY_);

  // &&& FOR NOW UNUSED. KEEP IT IN CASE WE WANT TO USE IT IN THE FUTURE
  // Bad Pixels have their charge set to 0 in the clusterizer
  //hasBadPixels_ = false;
  //for(unsigned int i=0; i<theClusterParam.theCluster->pixelADC().size(); ++i) {
  //if(theClusterParam.theCluster->pixelADC()[i] == 0) { hasBadPixels_ = true; break;}
  //}

  theClusterParam.spansTwoROCs_ = theDetParam.theTopol->containsBigPixelInX(minInX, maxInX) ||
                                  theDetParam.theTopol->containsBigPixelInY(minInY, maxInY);
}

//-----------------------------------------------------------------------------
//  Compute alpha_ and beta_ from the LocalTrajectoryParameters.
//  Note: should become const after both localParameters() become const.
//-----------------------------------------------------------------------------
void PixelCPEBase::computeAnglesFromTrajectory(DetParam const& theDetParam,
                                               ClusterParam& theClusterParam,
                                               const LocalTrajectoryParameters& ltp) const {
  theClusterParam.cotalpha = ltp.dxdz();
  theClusterParam.cotbeta = ltp.dydz();

  LocalPoint trk_lp = ltp.position();
  theClusterParam.trk_lp_x = trk_lp.x();
  theClusterParam.trk_lp_y = trk_lp.y();

  theClusterParam.with_track_angle = true;

  // GG: needed to correct for bows/kinks
  theClusterParam.loc_trk_pred = Topology::LocalTrackPred(
      theClusterParam.trk_lp_x, theClusterParam.trk_lp_y, theClusterParam.cotalpha, theClusterParam.cotbeta);
}

//-----------------------------------------------------------------------------
//  Estimate theAlpha for barrel, based on the det position.
//  &&& Needs to be consolidated from the above.
//-----------------------------------------------------------------------------
//float
//PixelCPEBase::estimatedAlphaForBarrel(float centerx) const
//{
//  float tanalpha = theSign * (centerx-theOffsetX) * thePitchX / theDetR;
//  return PI/2.0 - atan(tanalpha);
//}

//-----------------------------------------------------------------------------
//  Compute alpha_ and beta_ from the position of this DetUnit.
//  &&& DOES NOT WORK FOR NOW. d.k. 6/06
// The angles from dets are calculated internaly in the PixelCPEInitial class
//-----------------------------------------------------------------------------
// G. Giurgiu, 12/01/06 : implement the function
void PixelCPEBase::computeAnglesFromDetPosition(DetParam const& theDetParam, ClusterParam& theClusterParam) const {
  LocalPoint lp = theDetParam.theTopol->localPosition(
      MeasurementPoint(theClusterParam.theCluster->x(), theClusterParam.theCluster->y()));
  auto gvx = lp.x() - theDetParam.theOrigin.x();
  auto gvy = lp.y() - theDetParam.theOrigin.y();
  auto gvz = -1.f / theDetParam.theOrigin.z();
  //--- Note that the normalization is not required as only the ratio used

  //theClusterParam.zneg = (gvz < 0); // Not used, AH

  // calculate angles
  theClusterParam.cotalpha = gvx * gvz;
  theClusterParam.cotbeta = gvy * gvz;

  theClusterParam.with_track_angle = false;

  /*
    // used only in dberror param...
    auto alpha = HALF_PI - std::atan(cotalpha_);
    auto beta = HALF_PI - std::atan(cotbeta_);
    if (zneg) { beta -=PI; alpha -=PI;}
    
    auto alpha_ = atan2( gv_dot_gvz, gv_dot_gvx );
    auto beta_  = atan2( gv_dot_gvz, gv_dot_gvy );
    
    assert(std::abs(std::round(alpha*10000.f)-std::round(alpha_*10000.f))<2);
    assert(std::abs(std::round(beta*10000.f)-std::round(beta_*10000.f))<2);
    */
}

//------------------------------------------------------------------------
PixelCPEBase::DetParam const& PixelCPEBase::detParam(const GeomDetUnit& det) const {
  auto i = det.index();
  //cout << "get parameters of detector " << i << endl;
  assert(i < int(m_DetParams.size()));
  //if (i>=int(m_DetParams.size())) m_DetParams.resize(i+1);  // should never happen!
  const DetParam& p = m_DetParams[i];
  return p;
}

//-----------------------------------------------------------------------------
//  Drift direction.
//  Works OK for barrel and forward.
//  The formulas used for dir_x,y,z have to be exactly the same as the ones
//  used in the digitizer (SiPixelDigitizerAlgorithm.cc).
//  &&& PM: needs to be consolidated, discuss with PS.
//-----------------------------------------------------------------------------
LocalVector PixelCPEBase::driftDirection(DetParam& theDetParam, GlobalVector bfield) const {
  Frame detFrame(theDetParam.theDet->surface().position(), theDetParam.theDet->surface().rotation());
  LocalVector Bfield = detFrame.toLocal(bfield);
  return driftDirection(theDetParam, Bfield);
}

LocalVector PixelCPEBase::driftDirection(DetParam& theDetParam, LocalVector Bfield) const {
  // Use LA from DB or from config
  float langle = 0.;
  if (!useLAOffsetFromConfig_) {     // get it from DB
    if (lorentzAngle_ != nullptr) {  // a real LA object
      langle = lorentzAngle_->getLorentzAngle(theDetParam.theDet->geographicalId().rawId());
      LogDebug("PixelCPEBase::driftDirection()")
          << " la " << langle << " " << theDetParam.theDet->geographicalId().rawId() << endl;
    } else {                                                                                      // no LA, unused
      langle = 0;                                                                                 // set to a fake value
      LogDebug("PixelCPEBase::driftDirection()") << " LA object is NULL, assume LA = 0" << endl;  //dk
    }
    LogDebug("PixelCPEBase::driftDirection()") << " Will use LA Offset from DB " << langle << endl;
  } else {  // from config file
    langle = lAOffset_;
    LogDebug("PixelCPEBase::driftDirection()") << " Will use LA Offset from config " << langle << endl;
  }

  // Now do the LA width stuff
  theDetParam.widthLAFractionX = 1.;  // predefine to 1 (default) if things fail
  theDetParam.widthLAFractionY = 1.;

  // Compute the charge width, generic only
  if (theFlag_ == 0) {
    if (useLAWidthFromDB_ && (lorentzAngleWidth_ != nullptr)) {
      // take it from a separate, special LA DB object (forWidth)

      auto langleWidth = lorentzAngleWidth_->getLorentzAngle(theDetParam.theDet->geographicalId().rawId());
      if (langleWidth != 0.0)
        theDetParam.widthLAFractionX = std::abs(langleWidth / langle);
      // leave the widthLAFractionY=1.
      //cout<<" LAWidth lorentz width "<<theDetParam.widthLAFractionX<<" "<<theDetParam.widthLAFractionY<<endl;

    } else if (useLAWidthFromConfig_) {  // get from config

      double lAWidth = 0;
      if (GeomDetEnumerators::isTrackerPixel(theDetParam.thePart) && GeomDetEnumerators::isBarrel(theDetParam.thePart))
        lAWidth = lAWidthBPix_;  // barrel
      else
        lAWidth = lAWidthFPix_;

      if (langle != 0.0)
        theDetParam.widthLAFractionX = std::abs(lAWidth / langle);
      // fix the FractionY at 1

      //cout<<" Lorentz width from config "<<theDetParam.widthLAFractionX<<" "<<theDetParam.widthLAFractionY<<endl;

    } else {  // get if from the offset LA (old method used until 2013)
              // do nothing
      //cout<<" Old default LA width method "<<theDetParam.widthLAFractionX<<" "<<theDetParam.widthLAFractionY<<endl;
    }

    //cout<<" Final LA fraction  "<<theDetParam.widthLAFractionX<<" "<<theDetParam.widthLAFractionY<<endl;

  }  // if flag

  float alpha2 = alpha2Order ? langle * langle : 0;  //

  // **********************************************************************
  // Our convention is the following:
  // +x is defined by the direction of the Lorentz drift!
  // +z is defined by the direction of E field (so electrons always go into -z!)
  // +y is defined by +x and +z, and it turns out to be always opposite to the +B field.
  // **********************************************************************

  float dir_x = -(langle * Bfield.y() + alpha2 * Bfield.z() * Bfield.x());
  float dir_y = (langle * Bfield.x() - alpha2 * Bfield.z() * Bfield.y());
  float dir_z = -(1.f + alpha2 * Bfield.z() * Bfield.z());
  auto scale = 1.f / std::abs(dir_z);                  // same as 1 + alpha2*Bfield.z()*Bfield.z()
  LocalVector dd(dir_x * scale, dir_y * scale, -1.f);  // last is -1 !

  LogDebug("PixelCPEBase") << " The drift direction in local coordinate is " << dd;

  return dd;
}

//-----------------------------------------------------------------------------
//  One-shot computation of the driftDirection and both lorentz shifts
//-----------------------------------------------------------------------------
void PixelCPEBase::computeLorentzShifts(DetParam& theDetParam) const {
  // Max shift (at the other side of the sensor) in cm
  theDetParam.lorentzShiftInCmX =
      theDetParam.driftDirection.x() / theDetParam.driftDirection.z() * theDetParam.theThickness;  //
  theDetParam.lorentzShiftInCmY =
      theDetParam.driftDirection.y() / theDetParam.driftDirection.z() * theDetParam.theThickness;  //

  LogDebug("PixelCPEBase::computeLorentzShifts()")
      << " lorentzShiftsInCmX,Y = " << theDetParam.lorentzShiftInCmX << " " << theDetParam.lorentzShiftInCmY << " "
      << theDetParam.driftDirection;
}

//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
SiPixelRecHitQuality::QualWordType PixelCPEBase::rawQualityWord(ClusterParam& theClusterParam) const {
  SiPixelRecHitQuality::QualWordType qualWord(0);
  if (theClusterParam.hasFilledProb_) {
    float probabilityXY = 0;
    if (theClusterParam.filled_from_2d)
      probabilityXY = theClusterParam.probabilityX_;
    else if (theClusterParam.probabilityX_ != 0 && theClusterParam.probabilityY_ != 0)
      probabilityXY = theClusterParam.probabilityX_ * theClusterParam.probabilityY_ *
                      (1.f - std::log(theClusterParam.probabilityX_ * theClusterParam.probabilityY_));
    SiPixelRecHitQuality::thePacking.setProbabilityXY(probabilityXY, qualWord);

    SiPixelRecHitQuality::thePacking.setProbabilityQ(theClusterParam.probabilityQ_, qualWord);
  }
  SiPixelRecHitQuality::thePacking.setQBin(theClusterParam.qBin_, qualWord);

  SiPixelRecHitQuality::thePacking.setIsOnEdge(theClusterParam.isOnEdge_, qualWord);

  SiPixelRecHitQuality::thePacking.setHasBadPixels(theClusterParam.hasBadPixels_, qualWord);

  SiPixelRecHitQuality::thePacking.setSpansTwoROCs(theClusterParam.spansTwoROCs_, qualWord);

  SiPixelRecHitQuality::thePacking.setHasFilledProb(theClusterParam.hasFilledProb_, qualWord);

  return qualWord;
}

void PixelCPEBase::fillPSetDescription(edm::ParameterSetDescription& desc) {
  desc.add<bool>("LoadTemplatesFromDB", true);
  desc.add<bool>("Alpha2Order", true);
  desc.add<int>("ClusterProbComputationFlag", 0);
  desc.add<bool>("useLAWidthFromDB", true);
  desc.add<double>("lAOffset", 0.0);
  desc.add<double>("lAWidthBPix", 0.0);
  desc.add<double>("lAWidthFPix", 0.0);
  desc.add<bool>("doLorentzFromAlignment", false);
  desc.add<bool>("useLAFromDB", true);
}