FastTimingCommon/src/ETLDeviceSim.cc

0001 #include "CLHEP/Units/GlobalPhysicalConstants.h"
0002 #include "SimFastTiming/FastTimingCommon/interface/ETLDeviceSim.h"
0003 #include "DataFormats/Math/interface/GeantUnits.h"
0004
0005 #include "DataFormats/DetId/interface/DetId.h"
0006 #include "DataFormats/ForwardDetId/interface/MTDDetId.h"
0007 #include "DataFormats/ForwardDetId/interface/ETLDetId.h"
0008 #include "FWCore/Framework/interface/ConsumesCollector.h"
0009
0010 #include "Geometry/CommonDetUnit/interface/GeomDetType.h"
0011 #include "Geometry/CommonTopologies/interface/PixelTopology.h"
0012 #include "Geometry/MTDGeometryBuilder/interface/ProxyMTDTopology.h"
0013 #include "Geometry/MTDGeometryBuilder/interface/RectangularMTDTopology.h"
0014
0015 ETLDeviceSim::ETLDeviceSim(const edm::ParameterSet& pset, edm::ConsumesCollector iC)
0016     : geomToken_(iC.esConsumes()),
0017       geom_(nullptr),
0018       MIPPerMeV_(1.0 / pset.getParameter<double>("meVPerMIP")),
0019       bxTime_(pset.getParameter<double>("bxTime")),
0020       tofDelay_(pset.getParameter<double>("tofDelay")) {}
0021
0022 void ETLDeviceSim::getEventSetup(const edm::EventSetup& evs) { geom_ = &evs.getData(geomToken_); }
0023
0024 void ETLDeviceSim::getHitsResponse(const std::vector<std::tuple<int, uint32_t, float> >& hitRefs,
0025                                    const edm::Handle<edm::PSimHitContainer>& hits,
0026                                    mtd_digitizer::MTDSimHitDataAccumulator* simHitAccumulator,
0027                                    CLHEP::HepRandomEngine* hre) {
0028   using namespace geant_units::operators;
0029
0030   //loop over sorted hits
0031   const int nchits = hitRefs.size();
0032   LogTrace("ETLDeviceSim") << "Processing " << nchits << " SIM hits";
0033   for (int i = 0; i < nchits; ++i) {
0034     const int hitidx = std::get<0>(hitRefs[i]);
0035     const uint32_t id = std::get<1>(hitRefs[i]);
0036     const MTDDetId detId(id);
0037
0038     // Safety check (this should never happen, it should be an exception
0039     if (detId.det() != DetId::Forward || detId.mtdSubDetector() != 2) {
0040       throw cms::Exception("ETLDeviceSim")
0041           << "got a DetId that was not ETL: Det = " << detId.det() << "  subDet = " << detId.mtdSubDetector();
0042     }
0043
0044     if (id == 0)
0045       continue;  // to be ignored at RECO level
0046
0047     ETLDetId etlid(detId);
0048     DetId geoId = ETLDetId(etlid.mtdSide(), etlid.mtdRR(), etlid.module(), etlid.modType());
0049     const MTDGeomDet* thedet = geom_->idToDet(geoId);
0050     if (thedet == nullptr) {
0051       throw cms::Exception("ETLDeviceSim") << "GeographicalID: " << std::hex << geoId.rawId() << " (" << detId.rawId()
0052                                            << ") is invalid!" << std::dec << std::endl;
0053     }
0054     const ProxyMTDTopology& topoproxy = static_cast<const ProxyMTDTopology&>(thedet->topology());
0055     const RectangularMTDTopology& topo = static_cast<const RectangularMTDTopology&>(topoproxy.specificTopology());
0056
0057     const float toa = std::get<2>(hitRefs[i]) + tofDelay_;
0058     const PSimHit& hit = hits->at(hitidx);
0059     const float charge = convertGeVToMeV(hit.energyLoss()) * MIPPerMeV_;
0060
0061     // calculate the simhit row and column
0062     const auto& position = hit.localPosition();
0063     // ETL is already in module-local coordinates so just scale to cm from mm
0064     Local3DPoint simscaled(convertMmToCm(position.x()), convertMmToCm(position.y()), convertMmToCm(position.z()));
0065     //The following lines check whether the pixel point is actually out of the active area.
0066     //If that is the case it simply ignores the point but in the future some more sophisticated function could be applied.
0067     if (!topo.isInPixel(simscaled)) {
0068       LogDebug("ETLDeviceSim") << "Skipping hit ouf of pixel # " << hitidx << " DetId " << etlid.rawId() << " tof "
0069                                << toa;
0070       continue;
0071     }
0072     const auto& thepixel = topo.pixel(simscaled);
0073     const uint8_t row(thepixel.first), col(thepixel.second);
0074
0075     LogDebug("ETLDeviceSim") << "Processing hit in pixel # " << hitidx << " DetId " << etlid.rawId() << " row/col "
0076                              << (uint32_t)row << " " << (uint32_t)col << " tof " << toa;
0077
0078     auto simHitIt =
0079         simHitAccumulator->emplace(mtd_digitizer::MTDCellId(id, row, col), mtd_digitizer::MTDCellInfo()).first;
0080
0081     // Accumulate in 15 buckets of 25ns (9 pre-samples, 1 in-time, 5 post-samples)
0082     const int itime = std::floor(toa / bxTime_) + 9;
0083     if (itime < 0 || itime > 14)
0084       continue;
0085
0086     // Check if time index is ok and store energy
0087     if (itime >= (int)simHitIt->second.hit_info[0].size())
0088       continue;
0089
0090     (simHitIt->second).hit_info[0][itime] += charge;
0091
0092     // Store the time of the first SimHit in the right DataFrame bucket
0093     const float tof = toa - (itime - 9) * bxTime_;
0094
0095     if ((simHitIt->second).hit_info[1][itime] == 0. || tof < (simHitIt->second).hit_info[1][itime]) {
0096       (simHitIt->second).hit_info[1][itime] = tof;
0097     }
0098   }
0099 }