ZdcNumberingScheme.cc

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// File: ZdcNumberingScheme.cc
// Date: 02.04
// Description: Numbering scheme for Zdc
// Modifications:
#include "SimG4CMS/Forward/interface/ZdcNumberingScheme.h"
#include "DataFormats/HcalDetId/interface/HcalZDCDetId.h"
#include "CLHEP/Units/GlobalSystemOfUnits.h"
#include <iostream>
#undef debug

ZdcNumberingScheme::ZdcNumberingScheme(int iv) {
  verbosity = iv;
  if (verbosity > 0)
    std::cout << "Creating ZDCNumberingScheme" << std::endl;
}

ZdcNumberingScheme::~ZdcNumberingScheme() {
  if (verbosity > 0)
    std::cout << " Deleting ZdcNumberingScheme" << std::endl;
}

void ZdcNumberingScheme::setVerbosity(const int iv) { verbosity = iv; }

unsigned int ZdcNumberingScheme::getUnitID(const G4Step* aStep) const {
  uint32_t index = 0;
  int level = detectorLevel(aStep);

  if (level > 0) {
    int* copyno = new int[level];
    G4String* name = new G4String[level];

    detectorLevel(aStep, level, copyno, name);

    int zside = 0;
    int channel = 0;
    int fiber = 0;
    int layer = 0;
    HcalZDCDetId::Section section = HcalZDCDetId::Unknown;

    for (int ich = 0; ich < level; ich++) {
      if (name[ich] == "ZDC") {
        if (copyno[ich] == 1)
          zside = 1;
        if (copyno[ich] == 2)
          zside = -1;
      } else if (name[ich] == "ZDC_EMLayer") {
        section = HcalZDCDetId::EM;
#ifdef debug
        layer = copyno[ich];
#endif
      } else if (name[ich] == "ZDC_EMFiber") {
        fiber = copyno[ich];
        if (fiber < 20)
          channel = 1;
        else if (fiber < 39)
          channel = 2;
        else if (fiber < 58)
          channel = 3;
        else if (fiber < 77)
          channel = 4;
        else
          channel = 5;
      } else if (name[ich] == "ZDC_LumLayer") {
        section = HcalZDCDetId::LUM;
        layer = copyno[ich];
        channel = layer;
      } else if (name[ich] == "ZDC_HadLayer") {
        section = HcalZDCDetId::HAD;
        layer = copyno[ich];
        if (layer < 6)
          channel = 1;
        else if (layer < 12)
          channel = 2;
        else if (layer < 18)
          channel = 3;
        else
          channel = 4;
      }
#ifdef debug
      else if (name[ich] == "ZDC_LumGas") {
        fiber = 1;
      } else if (name[ich] == "ZDC_HadFiber") {
        fiber = copyno[ich];
      }
#endif
    }

#ifdef debug
    unsigned intindex = 0;
    intindex = packZdcIndex(section, layer, fiber, channel, zside);
#endif

    bool true_for_positive_eta = true;
    if (zside == -1)
      true_for_positive_eta = false;

    HcalZDCDetId zdcId(section, true_for_positive_eta, channel);
    index = zdcId.rawId();

#ifdef debug
    std::cout << "DetectorId: ";
    std::cout << zdcId << std::endl;

    std::cout << "ZdcNumberingScheme:"
              << "  getUnitID - # of levels = " << level << std::endl;
    for (int ich = 0; ich < level; ich++)
      std::cout << "  " << ich << ": copyno " << copyno[ich] << " name=" << name[ich] << "  section " << section
                << " zside " << zside << " layer " << layer << " fiber " << fiber << " channel " << channel
                << "packedIndex =" << intindex << " detId raw: " << index << std::endl;

#endif

    delete[] copyno;
    delete[] name;
  }

  return index;
}

unsigned ZdcNumberingScheme::packZdcIndex(int section, int layer, int fiber, int channel, int z) {
  unsigned int idx = ((z - 1) & 1) << 20;  //bit 20
  idx += (channel & 7) << 17;              //bits 17-19
  idx += (fiber & 255) << 9;               //bits 9-16
  idx += (layer & 127) << 2;               //bits 2-8
  idx += (section & 3);                    //bits 0-1

#ifdef debug
  std::cout << "ZDC packing: section " << section << " layer  " << layer << " fiber " << fiber << " channel " << channel
            << " zside " << z << "idx: " << idx << std::endl;
  int newsubdet, newlayer, newfiber, newchannel, newz;
  unpackZdcIndex(idx, newsubdet, newlayer, newfiber, newchannel, newz);
#endif

  return idx;
}

void ZdcNumberingScheme::unpackZdcIndex(
    const unsigned int& idx, int& section, int& layer, int& fiber, int& channel, int& z) {
  z = 1 + ((idx >> 20) & 1);
  channel = (idx >> 17) & 7;
  fiber = (idx >> 9) & 255;
  layer = (idx >> 2) & 127;
  section = idx & 3;

#ifdef debug
  std::cout << "ZDC unpacking: idx:" << idx << " -> section " << section << " layer " << layer << " fiber " << fiber
            << " channel " << channel << " zside " << z << std::endl;
#endif
}

int ZdcNumberingScheme::detectorLevel(const G4Step* aStep) const {
  //Find number of levels
  const G4VTouchable* touch = aStep->GetPreStepPoint()->GetTouchable();
  int level = 0;
  if (touch)
    level = ((touch->GetHistoryDepth()) + 1);
  return level;
}

void ZdcNumberingScheme::detectorLevel(const G4Step* aStep, int& level, int* copyno, G4String* name) const {
  //Get name and copy numbers
  if (level > 0) {
    const G4VTouchable* touch = aStep->GetPreStepPoint()->GetTouchable();
    for (int ii = 0; ii < level; ii++) {
      int i = level - ii - 1;
      name[ii] = touch->GetVolume(i)->GetName();
      copyno[ii] = touch->GetReplicaNumber(i);
    }
  }
}