SimulationDrawer.cxx

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#include <iomanip>
#include <algorithm>

#include "TParticle.h"
#include "TLine.h"
#include "TLatex.h"
#include "TPolyMarker3D.h"
#include "TPolyMarker.h"
#include "TPolyLine.h"
#include "TPolyLine3D.h"
#include "TDatabasePDG.h"

#include "lareventdisplay/EventDisplay/SimulationDrawer.h"
#include "nutools/EventDisplayBase/View2D.h"
#include "nutools/EventDisplayBase/View3D.h"
#include "larcore/CoreUtils/ServiceUtil.h"
#include "larcore/Geometry/Geometry.h"
#include "larcorealg/Geometry/PlaneGeo.h"
#include "larcorealg/Geometry/TPCGeo.h"
#include "nusimdata/SimulationBase/MCTruth.h"
#include "nusimdata/SimulationBase/MCParticle.h"
#include "larsim/Simulation/LArVoxelData.h"
#include "larsim/Simulation/LArVoxelList.h"
#include "larsim/Simulation/SimListUtils.h"
#include "lareventdisplay/EventDisplay/Style.h"
#include "lareventdisplay/EventDisplay/SimulationDrawingOptions.h"
#include "lareventdisplay/EventDisplay/RawDrawingOptions.h"
#include "lardata/DetectorInfoServices/DetectorPropertiesService.h"
#include "lardataalg/DetectorInfo/DetectorProperties.h"
#include "lardata/DetectorInfoServices/DetectorClocksService.h"
#include "larsim/MCCheater/BackTrackerService.h"
#include "larsim/MCCheater/ParticleInventoryService.h"

#include "larevt/SpaceChargeServices/SpaceChargeService.h"

#include "art/Framework/Services/Registry/ServiceHandle.h"
#include "art/Framework/Principal/View.h"
#include "art/Framework/Principal/Event.h"
#include "messagefacility/MessageLogger/MessageLogger.h"

namespace {
  // Utility function to make uniform error messages.
  void writeErrMsg(const char* fcn,
                   cet::exception const& e)
  {
    mf::LogWarning("SimulationDrawer") << "SimulationDrawer::" << fcn
                                       << " failed with message:\n"
                                       << e;
  }
}

namespace evd{

SimulationDrawer::SimulationDrawer()
{
    // For now only draw cryostat=0.
    art::ServiceHandle<geo::Geometry> geom;
    minx = 1e9;
    maxx = -1e9;
    miny = 1e9;
    maxy = -1e9;
    minz = 1e9;
    maxz = -1e9;
    
    for(size_t cryoIdx = 0; cryoIdx < geom->Ncryostats(); cryoIdx++)
    {
        const geo::CryostatGeo& cryoGeo = geom->Cryostat(cryoIdx);
        
        for (size_t tpcIdx = 0; tpcIdx < cryoGeo.NTPC(); tpcIdx++)
        {
            const geo::TPCGeo& tpc = cryoGeo.TPC(tpcIdx);
        
            std::cout << "Cryo/TPC idx: " << cryoIdx << "/" << tpcIdx << ", TPC center: " << tpc.GetCenter()[0] << ", " << tpc.GetCenter()[1] << ", " << tpc.GetCenter()[2] << std::endl;
            std::cout << "         TPC Active center: " << tpc.GetActiveVolumeCenter()[0] << ", " << tpc.GetActiveVolumeCenter()[1] << ", " << tpc.GetActiveVolumeCenter()[2] << ", H/W/L: " << tpc.ActiveHalfHeight() << "/" << tpc.ActiveHalfWidth() << "/" << tpc.ActiveLength() << std::endl;

            if (minx>tpc.GetCenter()[0]-tpc.HalfWidth())
                minx = tpc.GetCenter()[0]-tpc.HalfWidth();
            if (maxx<tpc.GetCenter()[0]+tpc.HalfWidth())
                maxx = tpc.GetCenter()[0]+tpc.HalfWidth();
            if (miny>tpc.GetCenter()[1]-tpc.HalfHeight())
                miny = tpc.GetCenter()[1]-tpc.HalfHeight();
            if (maxy<tpc.GetCenter()[1]+tpc.HalfHeight())
                maxy = tpc.GetCenter()[1]+tpc.HalfHeight();
            if (minz>tpc.GetCenter()[2]-tpc.Length()/2.)
                minz = tpc.GetCenter()[2]-tpc.Length()/2.;
            if (maxz<tpc.GetCenter()[2]+tpc.Length()/2.)
                maxz = tpc.GetCenter()[2]+tpc.Length()/2.;
        
            std::cout << "        minx/maxx: " << minx << "/" << maxx << ", miny/maxy: " << miny << "/" << maxy << ", minz/miny: " << minz << "/" << maxz << std::endl;
        }
    }
}

  //......................................................................

  SimulationDrawer::~SimulationDrawer()
  {
  }

  //......................................................................

  void SimulationDrawer::MCTruthShortText(const art::Event& evt,
                                          evdb::View2D*     view)
  {

    if( evt.isRealData() ) return;

    art::ServiceHandle<evd::SimulationDrawingOptions> drawopt;
    // Skip drawing if option is turned off
    if (!drawopt->fShowMCTruthText) return;

    std::vector<const simb::MCTruth*> mctruth;
    this->GetMCTruth(evt, mctruth);
    
    for (unsigned int i=0; i<mctruth.size(); ++i) {
        std::string mctext;
        bool firstin  = true;
        bool firstout = true;
        std::string origin;
        std::string incoming;
        std::string outgoing;
        // Label cosmic rays -- others are pretty obvious
        if (mctruth[i]->Origin()==simb::kCosmicRay)  origin = "c-ray: ";
        int jmax = TMath::Min(20,mctruth[i]->NParticles());
        for (int j=0; j<jmax; ++j) {
            const simb::MCParticle& p = mctruth[i]->GetParticle(j);
            char buff[1024];
            if (p.P()>0.05) {
                sprintf(buff,"#color[%d]{%s #scale[0.75]{[%.1f GeV/c]}}",
                        Style::ColorFromPDG(p.PdgCode()),
                        Style::LatexName(p.PdgCode()),
                        p.P());
            }
            else {
                sprintf(buff,"#color[%d]{%s}",
                        Style::ColorFromPDG(p.PdgCode()),
                        Style::LatexName(p.PdgCode()));
            }
            if (p.StatusCode()==0) {
                if (firstin==false) incoming += " + ";
                incoming += buff;
                firstin = false;
            }
            if (p.StatusCode()==1) {
                if (firstout==false) outgoing += " + ";
                outgoing += buff;
                firstout = false;
            }
        } // loop on j particles
        if (origin=="" && incoming=="") {
            mctext = outgoing;
        }
        else {
            mctext = origin+incoming+" #rightarrow "+outgoing;
        }
        TLatex& latex = view->AddLatex(0.03, 0.2, mctext.c_str());
        latex.SetTextSize(0.6);

    } // loop on i mctruth objects
  }

  //......................................................................

  void SimulationDrawer::MCTruthLongText(const art::Event& evt,
                                         evdb::View2D* /*view*/) 
  {
      if( evt.isRealData() ) return;

      art::ServiceHandle<evd::SimulationDrawingOptions> drawopt;
      // Skip drawing if option is turned off
      if (!drawopt->fShowMCTruthText) return;

      std::vector<const simb::MCTruth*> mctruth;
      this->GetMCTruth(evt, mctruth);
      std::cout<<"\nMCTruth Ptcl trackID            PDG      P      T   Moth  Process\n";
      for (unsigned int i=0; i<mctruth.size(); ++i) {
          for (int j=0; j<mctruth[i]->NParticles(); ++j) {
            const simb::MCParticle& p = mctruth[i]->GetParticle(j);
            if(p.StatusCode() == 0 || p.StatusCode() == 1) {
              int KE = 1000 * (p.E() - p.Mass());
              std::cout<<std::right<<std::setw(7)<<i<<std::setw(5)<<j
              <<std::setw(8)<<p.TrackId()
              <<" "<<std::setw(14)<<Style::LatexName(p.PdgCode())
              <<std::setw(7)<<int(1000 * p.P())
              <<std::setw(7)<<KE<<std::setw(7)<<p.Mother()
              <<" "<<p.Process()
              <<"\n";
            }
/*
                std::cout << Style::LatexName(p.PdgCode())
                  << "\t\t" << p.E() << " GeV"
                  << "\t"   << "(" << p.P() << " GeV/c)"
                  << std::endl;
*/
          } // loop on j particles in list
      }
    std::cout<<"Note: Momentum, P, and kinetic energy, T, in MeV/c\n";
  } // MCTruthLongText


  //......................................................................
  //this is the method you would use to color code hits by the MC truth pdg value
  void SimulationDrawer::MCTruthVectors2D(const art::Event& evt,
                                          evdb::View2D*     view,
                                          unsigned int      plane)
  {
    if( evt.isRealData() ) return;
    
    const spacecharge::SpaceCharge* sce = lar::providerFrom<spacecharge::SpaceChargeService>();

    art::ServiceHandle<evd::SimulationDrawingOptions> drawopt;
    // If the option is turned off, there's nothing to do
    if (drawopt->fShowMCTruthVectors > 3) {
      std::cout<<"Unsupported ShowMCTruthVectors option (> 2)\n";
      return;
    }

    detinfo::DetectorProperties const* detprop = lar::providerFrom<detinfo::DetectorPropertiesService>();

    art::ServiceHandle<geo::Geometry>          geo;
    art::ServiceHandle<evd::RawDrawingOptions> rawopt;
    // get the x position of the plane in question
    double xyz1[3]  = {0.};
    double xyz2[3] = {0.};
    // shift the truth by a fixed amount so it doesn't overlay the reco
    double xShift = -2;
    
    static bool first = true;
    if(first) {
      std::cout<<"******** Show MCTruth (Genie) particles when ShowMCTruthVectors = 1 or 3 ******** \n";
      std::cout<<"  MCTruth vectors corrected for space charge? "<<sce->EnableCorrSCE()<<" and shifted by "<<xShift<<" cm in X\n";
      std::cout<<"  Neutrons and photons drawn with dotted lines. \n";
      std::cout<<"  Red = e+/-, nue, nuebar. Blue = mu+/-, numu, numubar. Green = tau+/-, nutau, nutaubar.\n";
      std::cout<<"  Yellow = photons. Magenta = pions, protons and nuetrons.\n";
      std::cout<<"******** Show MCParticle (Geant) decay photons (e.g. from pizeros) when ShowMCTruthVectors = 2 or 3 ******** \n";
      std::cout<<"  Photons > 50 MeV are drawn as dotted lines corrected for space charge and are not shifted.\n";
      std::cout<<"  Decay photon end points are drawn at 2 interaction lengths (44 cm) from the start position.\n";
      std::cout<<"  Color: Green = (50 < E_photon < 100 MeV), Blue = (100 MeV < E_photon < 200 MeV), Red = (E_photon > 300 MeV).\n";
    }
    
    bool showTruth = (drawopt->fShowMCTruthVectors == 1 || drawopt->fShowMCTruthVectors == 3);
    bool showPhotons = (drawopt->fShowMCTruthVectors > 1);
    
    if(showTruth) {
      // Unpack and draw the MC vectors
      std::vector<const simb::MCTruth*> mctruth;
      this->GetMCTruth(evt, mctruth);
      
      for (size_t i = 0; i < mctruth.size(); ++i) {
        if (mctruth[i]->Origin() == simb::kCosmicRay) continue;
        for (int j = 0; j < mctruth[i]->NParticles(); ++j) {
          const simb::MCParticle& p = mctruth[i]->GetParticle(j);
          
          // Skip all but incoming and out-going particles
          if (!(p.StatusCode()==0 || p.StatusCode()==1)) continue;
          
          double r  = p.P()*10.0;           // Scale length so 10 cm = 1 GeV/c
          
          if (p.StatusCode() == 0) r = -r;  // Flip for incoming particles
          
          auto gptStart = geo::Point_t(p.Vx(),p.Vy(),p.Vz());
          geo::Point_t sceOffset {0, 0, 0};
          if(sce->EnableCorrSCE()) sceOffset = sce->GetPosOffsets(gptStart);
//          std::cout<<"Pos "<<std::fixed<<std::setprecision(1)<<gptStart.X()<<" "<<gptStart.Y()<<" "<<gptStart.Z();
//          std::cout<<" sceOffset "<<std::setprecision(1)<<sceOffset.X()<<" "<<sceOffset.Y()<<" "<<sceOffset.Z()<<"\n";
          xyz1[0]  = p.Vx() - sceOffset.X();
          xyz1[1]  = p.Vy() + sceOffset.Y();
          xyz1[2]  = p.Vz() + sceOffset.Z();
          xyz2[0] = xyz1[0] + r * p.Px()/p.P();
          xyz2[1] = xyz1[1] + r * p.Py()/p.P();
          xyz2[2] = xyz1[2] + r * p.Pz()/p.P();
          
          double w1 = geo->WireCoordinate(xyz1[1], xyz1[2], (int)plane, rawopt->fTPC, rawopt->fCryostat);
          double w2 = geo->WireCoordinate(xyz2[1], xyz2[2], (int)plane, rawopt->fTPC, rawopt->fCryostat);
          
          double time = detprop->ConvertXToTicks(xyz1[0] + xShift, (int)plane, rawopt->fTPC, rawopt->fCryostat);
          double time2 = detprop->ConvertXToTicks(xyz2[0] + xShift, (int)plane, rawopt->fTPC, rawopt->fCryostat);
          
          if(rawopt->fAxisOrientation < 1){
            TLine& l = view->AddLine(w1, time, w2, time2);
            evd::Style::FromPDG(l, p.PdgCode());
          }
          else{
            TLine& l = view->AddLine(time, w1, time2, w2);
            evd::Style::FromPDG(l, p.PdgCode());
          }
          // 
          
        } // loop on j particles in list
      } // loop on truths
    } // showTruth
    
    if(showPhotons) {
      // draw pizero photons with T > 30 MeV
      art::ServiceHandle<cheat::ParticleInventoryService> pi_serv;
      sim::ParticleList const& plist = pi_serv->ParticleList();
      if(plist.empty()) return;
      // photon interaction length approximate 
      double r = 44;
      for(sim::ParticleList::const_iterator ipart = plist.begin(); ipart != plist.end(); ++ipart) {
        simb::MCParticle* p = (*ipart).second;
        int trackID = p->TrackId();
        art::Ptr<simb::MCTruth> theTruth = pi_serv->TrackIdToMCTruth_P(trackID);
        if(theTruth->Origin() == simb::kCosmicRay) continue;
        if(p->PdgCode() != 22) continue;
        if(p->Process() != "Decay") continue;
        int TMeV = 1000 * (p->E() - p->Mass());
        if(TMeV < 30) continue;
        auto gptStart = geo::Point_t(p->Vx(),p->Vy(),p->Vz());
        geo::Point_t sceOffset {0, 0, 0};
        if(sce->EnableCorrSCE()) sceOffset = sce->GetPosOffsets(gptStart);
//        std::cout<<"Pos "<<std::fixed<<std::setprecision(1)<<gptStart.X()<<" "<<gptStart.Y()<<" "<<gptStart.Z();
//        std::cout<<" sceOffset "<<std::setprecision(1)<<sceOffset.X()<<" "<<sceOffset.Y()<<" "<<sceOffset.Z()<<"\n";
        xyz1[0]  = p->Vx() - sceOffset.X();
        xyz1[1]  = p->Vy() + sceOffset.Y();
        xyz1[2]  = p->Vz() + sceOffset.Z();
        xyz2[0] = xyz1[0] + r * p->Px()/p->P();
        xyz2[1] = xyz1[1] + r * p->Py()/p->P();
        xyz2[2] = xyz1[2] + r * p->Pz()/p->P();
        double w1 = geo->WireCoordinate(xyz1[1], xyz1[2], (int)plane, rawopt->fTPC, rawopt->fCryostat);
        double t1 = detprop->ConvertXToTicks(xyz1[0], (int)plane, rawopt->fTPC, rawopt->fCryostat);
        double w2 = geo->WireCoordinate(xyz2[1], xyz2[2], (int)plane, rawopt->fTPC, rawopt->fCryostat);
        double t2 = detprop->ConvertXToTicks(xyz2[0], (int)plane, rawopt->fTPC, rawopt->fCryostat);
        TLine& l = view->AddLine(w1, t1, w2, t2);
        l.SetLineWidth(2);
        l.SetLineStyle(kDotted);
        if(TMeV < 100) {
          l.SetLineColor(kGreen);
        } else if(TMeV < 200) {
          l.SetLineColor(kBlue);
        } else {
          l.SetLineColor(kRed);
        }
      } // ipart
    } // showPhotons
    
    first = false;
    
  } // MCTruthVectors2D

  //......................................................................
  //this method draws the true particle trajectories in 3D
void SimulationDrawer::MCTruth3D(const art::Event& evt,
                                 evdb::View3D*     view)
{
    if( evt.isRealData() ) return;

    art::ServiceHandle<evd::SimulationDrawingOptions> drawopt;
    // If the option is turned off, there's nothing to do
    if (!drawopt->fShowMCTruthTrajectories) return;
    
    // learn whether we want to draw the scintillation light too;
    // in fact, we don't care whether it's scintillation or not,
    // but it is photons with very low energy, close to the optical range
    bool const fDrawLight = drawopt->fShowScintillationLight;
    
    // Space charge service...
  //  const spacecharge::SpaceCharge* sce = lar::providerFrom<spacecharge::SpaceChargeService>();

    //  geo::GeometryCore const* geom = lar::providerFrom<geo::Geometry>();
    detinfo::DetectorProperties const* theDetector = lar::providerFrom<detinfo::DetectorPropertiesService>();
    detinfo::DetectorClocks     const* detClocks   = lar::providerFrom<detinfo::DetectorClocksService>();
    art::ServiceHandle<geo::Geometry>  geom;

    // get the particles from the Geant4 step
    std::vector<const simb::MCParticle*> plist;
    this->GetParticle(evt, plist);
      
    // Useful variables
    double xMinimum(-1.*(maxx-minx));
    double xMaximum( 2.*(maxx-minx));
    
    double xMinFromTicks = theDetector->ConvertTicksToX(0,0,0,0);
    double xMaxFromTicks = theDetector->ConvertTicksToX(theDetector->NumberTimeSamples(),0,0,0);
    
    std::cout << "# samples: " << theDetector->NumberTimeSamples() << ", min/max X: " << xMinFromTicks << "/" << xMaxFromTicks << ", xMinimum/xMaximum: " << xMinimum << "/" << xMaximum << std::endl;
    
    // Define a couple of colors for neutrals and if we gray it out...
    Color_t const scintillationColor = kMagenta;
    int neutralColor(12);
    int grayedColor(15);
    int neutrinoColor(38);
    
    // Use the LArVoxelList to get the true energy deposition locations as opposed to using MCTrajectories
    const sim::LArVoxelList voxels = sim::SimListUtils::GetLArVoxelList(evt,drawopt->fG4ModuleLabel);
      
    mf::LogDebug("SimulationDrawer") << "Starting loop over " << plist.size() << " McParticles, voxel list size is " << voxels.size() << std::endl;
      
    // Using the voxel information can be slow (see previous implementation of this code).
    // In order to speed things up we have modified the strategy:
    // 1) Make one pass through the list of voxels
    // 2) For each voxel, keep track of the MCParticle contributing energy to it and it's position
    //    which is done by keeping a map between the MCParticle and a vector of positions
    // 3) Then loop through the map to draw the particle trajectories.
    // One caveat is the need for MCParticles... and the voxels contain the track ids. So we'll need one
    // more loop to make a map of track id's and MCParticles.

    // First up is to build the map between track id's and associated MCParticles so we can recover when looping over voxels
    std::map<int, const simb::MCParticle*> trackToMcParticleMap;
      
    // Should we display the trajectories too?
    constexpr unsigned int MaxParticles = 100000000;
    double minPartEnergy(0.01);
    
    auto const* pDatabasePDG = TDatabasePDG::Instance();
    
    unsigned int nDrawnParticles = 0U;
    for (const simb::MCParticle* mcPart: plist) {
        trackToMcParticleMap[mcPart->TrackId()] = mcPart;
        
        // Quick loop through to draw trajectories...
        if (!drawopt->fShowMCTruthTrajectories) continue;
        
        // Is there an associated McTrajectory?
        const simb::MCTrajectory& mcTraj = mcPart->Trajectory();
        if (mcTraj.empty()) continue;
        
        int           const pdgCode(mcPart->PdgCode());
        int           const colorIdx
        { drawopt->fShowMCTruthColors? evd::Style::ColorFromPDG(mcPart->PdgCode()): grayedColor };
        TParticlePDG const* partPDG(pDatabasePDG->GetParticle(pdgCode));
        double        const partCharge = partPDG ? partPDG->Charge() : 0.;
        double        const partEnergy = mcPart->E();
        
        // is this a photon with less than 100 eV of energy?
        // (LArG4 scintillation photons are "Rootini", PDG code 0... *burp*)
        bool const isScintillationLight = ((pdgCode == 22) || (pdgCode == 0)) && (partEnergy < 1e-7);
        
        if (isScintillationLight) {
            // we do not apply any threshold, but we draw it only if requested
            if (!fDrawLight) continue;
        }
        else { // apply the "normal" threshold
            if (partEnergy < minPartEnergy) continue;
        }
        
        if (nDrawnParticles++ >= MaxParticles) {
          if (nDrawnParticles == MaxParticles) {
            mf::LogWarning("SimulationDrawer")
              << "Only " << nDrawnParticles << "/" << plist.size()
              << " MCParticle's will be displayed.";
          }
          continue; // too many!
        }
        
        /*
         * The following is meant to get the correct offset for drawing the particle trajectory
         * In particular, the cosmic rays will not be correctly placed without this
         * 
         * More specifically, the true location of the cosmic ray betrays the
         * expectation of the reader.
         * When we look at an event, we expect that if two particles are close
         * by, their observables (in our case, ionization tracks) will be as
         * close. The event display projects into a static picture everything
         * that happens at any time. This is not a big deal in a fast detector,
         * where the time window can be short, but has consequences of mixing
         * activity at different times for a LArTPC.
         * The slowness of TPCs is a major problem for physics. Here we are
         * facing a minor spin-off of that problem: if a pion is produced at a
         * certain position x by the neutrino interaction, and then one
         * millisecond later a cosmic rays passes at the same location, the
         * display will show both at the same position x, but the detection
         * will be delayed by the number of ticks the TDC counted in that one
         * millisecond. Reconstruction will not be fooled by the close distance
         * of the two tracks, but the display leads us to expect that confusion
         * /should/ arise.
         * 
         */
        //double g4Ticks(detClocks->TPCG4Time2Tick(mcPart->T())+theDetector->GetXTicksOffset(0,0,0)-theDetector->TriggerOffset());
        //double g4Ticks(detClocks->TPCG4Time2Tick(mcPart->T())+theDetector->GetXTicksOffset(0,0,0));
        double g4Ticks(detClocks->TPCG4Time2Tick(mcPart->T()));
        //double g4Ticks(detClocks->TPCG4Time2Tick(mcPart->T()));
        double xOffset(0.); //(theDetector->ConvertTicksToX(g4Ticks, 0, 0, 0));
        bool   xOffsetNotSet(true);
          // collect the points from this particle
        int const numTrajPoints = mcTraj.size();

        std::vector<double> hitPositions;
        hitPositions.reserve(3*numTrajPoints);
        std::size_t hitCount = 0U;
        
        
        for(int hitIdx = 0; hitIdx < numTrajPoints; hitIdx++)
        {
            double xPos = mcTraj.X(hitIdx);
            double yPos = mcTraj.Y(hitIdx);
            double zPos = mcTraj.Z(hitIdx);
        
            // If the original simulated hit did not occur in the TPC volume then don't draw it
            if (xPos < minx || xPos > maxx || yPos < miny || yPos > maxy|| zPos < minz || zPos > maxz) continue;
            
            // Check xOffset state and set if necessary
            if (xOffsetNotSet)
            {
                try
                {
                    auto const* pTPC = geom->PositionToTPCptr(geo::Point_t(xPos, yPos, zPos));
                    if (!pTPC) continue;
                    
                    geo::PlaneID const firstPlane { pTPC->ID(), 0 };
                    xMinFromTicks = theDetector->ConvertTicksToX(0, firstPlane);
                    xMaxFromTicks = theDetector->ConvertTicksToX(theDetector->NumberTimeSamples(), firstPlane);
                    
                    if (xMaxFromTicks < xMinFromTicks) std::swap(xMinFromTicks,xMaxFromTicks);

                    xOffset       = xMinFromTicks - theDetector->ConvertTicksToX(g4Ticks, firstPlane);
                    xOffsetNotSet = false;
                    xOffset = 0.;  // ?!?
                }
                catch(...) {continue;}
            }
        
            // Now move the hit position to correspond to the timing
            xPos += xOffset;
        
            // Check fiducial limits
            if (xPos > xMinFromTicks && xPos < xMaxFromTicks)
            {
                // Check for space charge offsets
//                if (spaceCharge->EnableSimEfieldSCE())
//                {
//                    std::vector<double> offsetVec = spaceCharge->GetPosOffsets(xPos,yPos,zPos);
//                    xPos += offsetVec[0] - 0.7;
//                    yPos -= offsetVec[1];
//                    zPos -= offsetVec[2];
//                }
                
              hitPositions.push_back(xPos);
              hitPositions.push_back(yPos);
              hitPositions.push_back(zPos);
              ++hitCount;
            }
        } // for hitIdx
        
        
        TPolyLine3D& pl(view->AddPolyLine3D(1, colorIdx, 1, 1));
        
        // Draw neutrals as a gray dotted line to help fade into background a bit...
        if (isScintillationLight) {
            pl.SetLineColor(scintillationColor);
            pl.SetLineStyle(kSolid);
            pl.SetLineWidth(1);
        }
        else if (partCharge == 0.)
        {
            pl.SetLineColor(neutralColor);
            pl.SetLineStyle(kDotted);
            pl.SetLineWidth(1);
        }
        pl.SetPolyLine(hitCount, hitPositions.data(), "");
    } // for mcPart
    
    
    // Now we set up and build the map between MCParticles and a vector of positions obtained from the voxels
    std::map<const simb::MCParticle*, std::vector<std::vector<double> > > partToPosMap;
      
    sim::LArVoxelList::const_iterator vxitr;
    for(vxitr = voxels.begin(); vxitr != voxels.end(); vxitr++)
    {
        const sim::LArVoxelData &vxd = (*vxitr).second;
        
        for(size_t partIdx = 0; partIdx < vxd.NumberParticles(); partIdx++)
        {
            if(vxd.Energy(partIdx) > drawopt->fMinEnergyDeposition)
            {
                int trackId = vxd.TrackID(partIdx);
                
                // It can be in some instances that mcPart here could be zero.
                const simb::MCParticle* mcPart = trackToMcParticleMap[trackId];
                
                partToPosMap[mcPart].push_back(std::vector<double>(3));
                
                partToPosMap[mcPart].back()[0] = vxd.VoxelID().X();
                partToPosMap[mcPart].back()[1] = vxd.VoxelID().Y();
                partToPosMap[mcPart].back()[2] = vxd.VoxelID().Z();
            }
        } // end if this track id is in the current voxel
    }// end loop over voxels
      
    // Finally ready for the main event! Simply loop through the map between MCParticle and positions to
    // draw the trajectories
    std::map<const simb::MCParticle*, std::vector<std::vector<double> > >::iterator partToPosMapItr;
      
    for(partToPosMapItr = partToPosMap.begin(); partToPosMapItr != partToPosMap.end(); partToPosMapItr++)
    {
        // Recover the McParticle, we'll need to access several data members so may as well dereference it
        const simb::MCParticle* mcPart = partToPosMapItr->first;
        
        // Apparently, it can happen that we get a null pointer here or maybe no points to plot
        if (!mcPart || partToPosMapItr->second.empty()) continue;
        
        // The following is meant to get the correct offset for drawing the particle trajectory
        // In particular, the cosmic rays will not be correctly placed without this
        //double g4Ticks(detClocks->TPCG4Time2Tick(mcPart->T())+theDetector->GetXTicksOffset(0,0,0)-theDetector->TriggerOffset());
        //double g4Ticks(detClocks->TPCG4Time2Tick(mcPart->T())+theDetector->GetXTicksOffset(0,0,0));
        double g4Ticks(detClocks->TPCG4Time2Tick(mcPart->T()));
//        double g4Ticks(detClocks->TPCG4Time2Tick(mcPart->T()));
        double xOffset(0.); //theDetector->ConvertTicksToX(g4Ticks, 0, 0, 0));
        bool   xOffsetNotSet(true);
        
        int colorIdx(evd::Style::ColorFromPDG(mcPart->PdgCode()));
        int markerIdx(kFullDotSmall);
        int markerSize(2);
        
        if (!drawopt->fShowMCTruthFullSize)
        {
            colorIdx   = grayedColor;
            markerIdx  = kDot;
            markerSize = 1;
        }
        
        std::unique_ptr<double[]> hitPositions(new double[3*partToPosMapItr->second.size()]);
        int                       hitCount(0);
        
        // Now loop over points and add to trajectory
        for(size_t posIdx = 0; posIdx < partToPosMapItr->second.size(); posIdx++)
        {
            const std::vector<double>& posVec = partToPosMapItr->second[posIdx];
            
            // Check xOffset state and set if necessary
            if (xOffsetNotSet)
            {
                double hitLocation[] = {posVec[0],posVec[1],posVec[2]};
                
                try
                {
                    const geo::CryostatGeo& cryoGeo = geom->PositionToCryostat(hitLocation);
                    int                     tpcIdx  = cryoGeo.FindTPCAtPosition(hitLocation, 1.);
                        
                    xMinFromTicks = theDetector->ConvertTicksToX(0,0,tpcIdx,cryoGeo.ID().Cryostat);
                    xMaxFromTicks = theDetector->ConvertTicksToX(theDetector->NumberTimeSamples(),0,tpcIdx,cryoGeo.ID().Cryostat);
                    
                    if (xMaxFromTicks < xMinFromTicks) std::swap(xMinFromTicks,xMaxFromTicks);

                    xOffset       = xMinFromTicks - theDetector->ConvertTicksToX(g4Ticks, 0, tpcIdx, cryoGeo.ID().Cryostat);
                    xOffsetNotSet = false;
                    xOffset = 0.;
                }
                catch(...) {continue;}
            }

            double xCoord = posVec[0] + xOffset;
            
            if (xCoord > xMinFromTicks && xCoord < xMaxFromTicks)
            {
                hitPositions[3*hitCount    ] = xCoord;
                hitPositions[3*hitCount + 1] = posVec[1];
                hitPositions[3*hitCount + 2] = posVec[2];
                hitCount++;
            }
        }
        
        TPolyMarker3D& pm = view->AddPolyMarker3D(1, colorIdx, markerIdx, markerSize);
        pm.SetPolyMarker(hitCount, hitPositions.get(), markerIdx);
    }
      
    // Finally, let's see if we can draw the incoming particle from the MCTruth information
    std::vector<const simb::MCTruth*> mctruth;
    this->GetMCTruth(evt, mctruth);

    // Loop through the MCTruth vector
    for (unsigned int idx = 0; idx < mctruth.size(); idx++)
    {
        // Go through each MCTruth object in the list
        for (int particleIdx = 0; particleIdx < mctruth[idx]->NParticles(); particleIdx++)
        {
            const simb::MCParticle& mcPart = mctruth[idx]->GetParticle(particleIdx);
            
            // A negative mother id indicates the "primary" particle
            if(mcPart.Mother() == -1 && mcPart.StatusCode() == 0)
            {
                mf::LogDebug("SimulationDrawer") << mcPart << std::endl;
                
                // Get position vector
                TVector3 particlePosition(mcPart.Vx(),mcPart.Vy(),mcPart.Vz());
                
                // Get direction vector (in opposite direction)
                TVector3 oppPartDir(-mcPart.Px(),-mcPart.Py(),-mcPart.Pz());
                
                if (oppPartDir.Mag2() > 0.) oppPartDir.SetMag(1.);
                
                double arcLenToDraw = -particlePosition.Z() / oppPartDir.CosTheta();
                
                // No point in drawing if arc length is zero (e.g. Ar nucleus)
                if (arcLenToDraw > 0.)
                {
                    // Draw the line, use an off color to be unique
                    TPolyLine3D& pl(view->AddPolyLine3D(2, neutrinoColor, 1, 2));
                
                    pl.SetPoint(0,particlePosition.X(),particlePosition.Y(),particlePosition.Z());
                
                    particlePosition += std::min(arcLenToDraw + 10.,1000.) * oppPartDir;
                
                    pl.SetPoint(1,particlePosition.X(),particlePosition.Y(),particlePosition.Z());
                }
            }
            // The particles we want to draw will be early in the list so break out if we didn't find them
            else break;
        } // loop on particles in list
    }
      
    return;
}

  //......................................................................
  //this method draws the true particle trajectories in 3D Ortho view.
  void SimulationDrawer::MCTruthOrtho(const art::Event& evt,
                                      evd::OrthoProj_t  proj,
                                      double            msize,
                                      evdb::View2D*     view)
  {
    if( evt.isRealData() ) return;

    art::ServiceHandle<evd::SimulationDrawingOptions> drawopt;
      
    // If the option is turned off, there's nothing to do
    if (!drawopt->fShowMCTruthTrajectories) return;
     
    geo::GeometryCore const* geom = lar::providerFrom<geo::Geometry>();
    detinfo::DetectorProperties const* theDetector = lar::providerFrom<detinfo::DetectorPropertiesService>();
    detinfo::DetectorClocks const* detClocks = lar::providerFrom<detinfo::DetectorClocksService>();
    
    // get the particles from the Geant4 step
    std::vector<const simb::MCParticle*> plist;
    this->GetParticle(evt, plist);
    
    // Useful variables

    //double detHalfWidth(geom->DetHalfWidth());
    double xMinimum(-1.*(maxx-minx));
    double xMaximum( 2.*(maxx-minx));
    
//    double detHalfHeight(geom->DetHalfHeight());
//    double zMinimum(0.);
//    double zMaximum(geom->DetLength());
    
    // Use the LArVoxelList to get the true energy deposition locations as opposed to using MCTrajectories
    const sim::LArVoxelList voxels = sim::SimListUtils::GetLArVoxelList(evt,drawopt->fG4ModuleLabel);
    
    mf::LogDebug("SimulationDrawer") << "Starting loop over " << plist.size() << " McParticles, voxel list size is " << voxels.size() << std::endl;
    
    // Using the voxel information can be slow (see previous implementation of this code).
    // In order to speed things up we have modified the strategy:
    // 1) Make one pass through the list of voxels
    // 2) For each voxel, keep track of the MCParticle contributing energy to it and it's position
    //    which is done by keeping a map between the MCParticle and a vector of positions
    // 3) Then loop through the map to draw the particle trajectories.
    // One caveat is the need for MCParticles... and the voxels contain the track ids. So we'll need one
    // more loop to make a map of track id's and MCParticles.
    
    // First up is to build the map between track id's and associated MCParticles so we can recover when looping over voxels
    std::map<int, const simb::MCParticle*> trackToMcParticleMap;
    
    // Should we display the trajectories too?
    bool   displayMcTrajectories(true);
    double minPartEnergy(0.025);
    
    double tpcminx = 1.0; double tpcmaxx = -1.0;
    double xOffset = 0.0; double g4Ticks = 0.0;
    double coeff = 0.0; double readoutwindowsize = 0.0;
    double vtx[3] = {0.0, 0.0, 0.0};
    for(size_t p = 0; p < plist.size(); ++p)
    {
        trackToMcParticleMap[plist[p]->TrackId()] = plist[p];
        
        // Quick loop through to drawn trajectories...
        if (displayMcTrajectories)
        {
            // Is there an associated McTrajectory?
            const simb::MCParticle*   mcPart = plist[p];
            const simb::MCTrajectory& mcTraj = mcPart->Trajectory();
            
            int           pdgCode(mcPart->PdgCode());
            TParticlePDG* partPDG(TDatabasePDG::Instance()->GetParticle(pdgCode));
            double        partCharge = partPDG ? partPDG->Charge() : 0.;
            double        partEnergy = mcPart->E();
            
            if (!mcTraj.empty() && partEnergy > minPartEnergy && mcPart->TrackId() < 100000000)
            {
                // collect the points from this particle
                int numTrajPoints = mcTraj.size();
                
                std::unique_ptr<double[]> hitPosX(new double[numTrajPoints]);
                std::unique_ptr<double[]> hitPosY(new double[numTrajPoints]);
                std::unique_ptr<double[]> hitPosZ(new double[numTrajPoints]);
                int                       hitCount(0);
                
                double xPos = mcTraj.X(0);
                double yPos = mcTraj.Y(0);
                double zPos = mcTraj.Z(0);
                
                tpcminx = 1.0; tpcmaxx = -1.0;
                xOffset = 0.0; g4Ticks = 0.0;
                vtx[0] = 0.0; vtx[1] = 0.0; vtx[2] = 0.0;
                coeff = 0.0; readoutwindowsize = 0.0;
                for(int hitIdx = 0; hitIdx < numTrajPoints; hitIdx++)
                {
                    xPos = mcTraj.X(hitIdx);
                    yPos = mcTraj.Y(hitIdx);
                    zPos = mcTraj.Z(hitIdx);
                    
                    // If the original simulated hit did not occur in the TPC volume then don't draw it
                    if (xPos < minx || xPos > maxx || yPos < miny || yPos > maxy|| zPos < minz || zPos > maxz) continue;
                                        
                    if ((xPos < tpcminx) || (xPos > tpcmaxx))
                    {
                        vtx[0] = xPos; vtx[1] = yPos; vtx[2] = zPos; 
                        geo::TPCID tpcid = geom->FindTPCAtPosition(vtx);                        
                        unsigned int cryo = geom->FindCryostatAtPosition(vtx);
                        
                        if (tpcid.isValid) 
                        {
                                unsigned int tpc = tpcid.TPC;
                                const geo::TPCGeo& tpcgeo = geom->GetElement(tpcid);            
                                tpcminx = tpcgeo.MinX(); tpcmaxx = tpcgeo.MaxX();
                                
                                coeff = theDetector->GetXTicksCoefficient(tpc, cryo);
                                readoutwindowsize = theDetector->ConvertTicksToX(theDetector->ReadOutWindowSize(), 0, tpc, cryo);
                                
                                // The following is meant to get the correct offset for drawing the particle trajectory
                                // In particular, the cosmic rays will not be correctly placed without this                 
                                g4Ticks = detClocks->TPCG4Time2Tick(mcPart->T())
                                        +theDetector->GetXTicksOffset(0, tpc, cryo)
                                        -theDetector->TriggerOffset();
                                
                                xOffset = theDetector->ConvertTicksToX(g4Ticks, 0, tpc, cryo);
                        }
                        else { xOffset = 0; tpcminx = 1.0; tpcmaxx = -1.0; coeff = 0.0; readoutwindowsize = 0.0;}
                    }
                            
                    // Now move the hit position to correspond to the timing
                    xPos += xOffset;
                    
                    bool inreadoutwindow = false;
                    if (coeff < 0) 
                    {
                        if ((xPos > readoutwindowsize) && (xPos < tpcmaxx)) inreadoutwindow = true;
                    }
                    else if (coeff > 0) 
                    {
                        if ((xPos > tpcminx) && (xPos < readoutwindowsize)) inreadoutwindow = true;     
                    }
                                    
                    if (!inreadoutwindow) continue;
                        
                    // Check fiducial limits
                    if (xPos > xMinimum && xPos < xMaximum)
                    {
                        hitPosX[hitCount] = xPos;
                        hitPosY[hitCount] = yPos;
                        hitPosZ[hitCount] = zPos;
                        hitCount++;
                    }
                          
                }
                
                TPolyLine& pl = view->AddPolyLine(1, evd::Style::ColorFromPDG(mcPart->PdgCode()), 1, 1); //kFullCircle, msize);
                
                // Draw neutrals as a gray dotted line to help fade into background a bit...
                if (partCharge == 0.)
                {
                    pl.SetLineColor(13);
                    pl.SetLineStyle(3);
                    pl.SetLineWidth(1);
                }

                if(proj == evd::kXY)
                    pl.SetPolyLine(hitCount, hitPosX.get(), hitPosY.get(), "");
                else if(proj == evd::kXZ)
                    pl.SetPolyLine(hitCount, hitPosZ.get(), hitPosX.get(), "");
                else if(proj == evd::kYZ)
                    pl.SetPolyLine(hitCount, hitPosZ.get(), hitPosY.get(), "");
            }
        }
    }
    
    // Now we set up and build the map between MCParticles and a vector of positions obtained from the voxels
    std::map<const simb::MCParticle*, std::vector<std::vector<double> > > partToPosMap;
    
    sim::LArVoxelList::const_iterator vxitr;
    for(vxitr = voxels.begin(); vxitr != voxels.end(); vxitr++)
    {
        const sim::LArVoxelData &vxd = (*vxitr).second;
        
        for(size_t partIdx = 0; partIdx < vxd.NumberParticles(); partIdx++)
        {
            if(vxd.Energy(partIdx) > drawopt->fMinEnergyDeposition)
            {
                int trackId = vxd.TrackID(partIdx);
                
                // It can be in some instances that mcPart here could be zero.
                const simb::MCParticle* mcPart = trackToMcParticleMap[trackId];
                             
                partToPosMap[mcPart].push_back(std::vector<double>(3));
                
                partToPosMap[mcPart].back()[0] = vxd.VoxelID().X();
                partToPosMap[mcPart].back()[1] = vxd.VoxelID().Y();
                partToPosMap[mcPart].back()[2] = vxd.VoxelID().Z();
            }
        } // end if this track id is in the current voxel
    }// end loop over voxels
    
    // Finally ready for the main event! Simply loop through the map between MCParticle and positions to
    // draw the trajectories
    std::map<const simb::MCParticle*, std::vector<std::vector<double> > >::iterator partToPosMapItr;

    for(partToPosMapItr = partToPosMap.begin(); partToPosMapItr != partToPosMap.end(); partToPosMapItr++)
    {
        // Recover the McParticle, we'll need to access several data members so may as well dereference it
        const simb::MCParticle* mcPart = partToPosMapItr->first;
        
        // Apparently, it can happen that we get a null pointer here or maybe no points to plot
        if (!mcPart || partToPosMapItr->second.empty()) continue;
        
        tpcminx = 1.0; tpcmaxx = -1.0;
        xOffset = 0.0; g4Ticks = 0.0;
        std::vector< std::array<double, 3> > posVecCorr;
        posVecCorr.reserve(partToPosMapItr->second.size());
        coeff = 0.0; readoutwindowsize = 0.0;
        
        // Now loop over points and add to trajectory
        for(size_t posIdx = 0; posIdx < partToPosMapItr->second.size(); posIdx++)
        {
                const std::vector<double>& posVec = partToPosMapItr->second[posIdx];
        
                if ((posVec[0] < tpcminx) || (posVec[0] > tpcmaxx))
                {
                        vtx[0] = posVec[0]; vtx[1] = posVec[1]; vtx[2] = posVec[2]; 
                        geo::TPCID tpcid = geom->FindTPCAtPosition(vtx);                        
                        unsigned int cryo = geom->FindCryostatAtPosition(vtx);
                        
                        if (tpcid.isValid)
                        {       
                                unsigned int tpc = tpcid.TPC;
                        
                                const geo::TPCGeo& tpcgeo = geom->GetElement(tpcid);            
                                tpcminx = tpcgeo.MinX(); tpcmaxx = tpcgeo.MaxX();
                        
                                coeff = theDetector->GetXTicksCoefficient(tpc, cryo);
                                readoutwindowsize = theDetector->ConvertTicksToX(theDetector->ReadOutWindowSize(), 0, tpc, cryo);
                                // The following is meant to get the correct offset for drawing the particle trajectory
                                // In particular, the cosmic rays will not be correctly placed without this                 
                                g4Ticks = detClocks->TPCG4Time2Tick(mcPart->T())
                                        +theDetector->GetXTicksOffset(0, tpc, cryo)
                                        -theDetector->TriggerOffset();
                                        
                                xOffset = theDetector->ConvertTicksToX(g4Ticks, 0, tpc, cryo);
                        }
                        else { xOffset = 0; tpcminx = 1.0; tpcmaxx = -1.0; coeff = 0.0; readoutwindowsize = 0.0; }      
                }
                
                double xCoord = posVec[0] + xOffset;
                
                bool inreadoutwindow = false;
                if (coeff < 0) 
                {
                        if ((xCoord > readoutwindowsize) && (xCoord < tpcmaxx)) inreadoutwindow = true;
                }                    
                else if (coeff > 0) 
                {
                        if ((xCoord > tpcminx) && (xCoord < readoutwindowsize)) inreadoutwindow = true; 
                }                           
                
                if (inreadoutwindow && (xCoord > xMinimum && xCoord < xMaximum))
                {
                        posVecCorr.push_back({{xCoord, posVec[1], posVec[2] }});                
                }
        }
        
        TPolyMarker& pm = view->AddPolyMarker(posVecCorr.size(), evd::Style::ColorFromPDG(mcPart->PdgCode()), kFullDotMedium, 2); //kFullCircle, msize);
        
        for (size_t p = 0; p < posVecCorr.size(); ++p)
        {
                        if(proj == evd::kXY)
                                pm.SetPoint(p, posVecCorr[p][0], posVecCorr[p][1]);
                        else if(proj == evd::kXZ)
                                pm.SetPoint(p, posVecCorr[p][2], posVecCorr[p][0]);
                        else if(proj == evd::kYZ)
                                pm.SetPoint(p, posVecCorr[p][2], posVecCorr[p][1]);
        }
    }
   
    return;
  }

  //......................................................................
  int SimulationDrawer::GetParticle(const art::Event&                     evt,
                                    std::vector<const simb::MCParticle*>& plist)
  {
    plist.clear();

    if( evt.isRealData() ) return 0;

    art::ServiceHandle<evd::SimulationDrawingOptions> drawopt;

    std::vector<const simb::MCParticle*> temp;

    art::View<simb::MCParticle> plcol;
    // use get by Type because there should only be one collection of these in the event
    try{
      evt.getView(drawopt->fG4ModuleLabel, plcol);
      for(unsigned int i = 0; i < plcol.vals().size(); ++i){
        temp.push_back(plcol.vals().at(i));
      }
      temp.swap(plist);
    }
    catch(cet::exception& e){
      writeErrMsg("GetRawDigits", e);
    }
  
    return plist.size();

  }

  //......................................................................

  int SimulationDrawer::GetMCTruth(const art::Event& evt,
                                   std::vector<const simb::MCTruth*>& mcvec) 
  {
    mcvec.clear();

    if( evt.isRealData() ) return 0;

    std::vector<const simb::MCTruth*> temp;

    std::vector< art::Handle< std::vector<simb::MCTruth> > > mctcol;
    // use get by Type because there should only be one collection of these in the event
    try{
      evt.getManyByType(mctcol);
      for(size_t mctc = 0; mctc < mctcol.size(); ++mctc){
        art::Handle< std::vector<simb::MCTruth> > mclistHandle = mctcol[mctc];

        for(size_t i = 0; i < mclistHandle->size(); ++i){
          temp.push_back(&(mclistHandle->at(i)));
        }
      }
      temp.swap(mcvec);
    }
    catch(cet::exception& e){
      writeErrMsg("GetMCTruth", e);
    }
  
    return mcvec.size();
  }


  //......................................................................

  void SimulationDrawer::HiLite(int trkId, bool dohilite)
  {
    fHighlite[trkId] = dohilite;
  }

}// namespace