MaterialMapping.cxx

Go to the documentation of this file.

/*
  Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
*/
 
// MaterialMapping.cxx, (c) ATLAS Detector software
 
// Gaudi Units
#include "GaudiKernel/SystemOfUnits.h"
//TrkDetDescr Algs, Interfaces, Utils
#include "MaterialMapping.h"
#include "TrkDetDescrUtils/GeometryStatics.h"
#include "TrkDetDescrUtils/LayerIndex.h"
#include "TrkDetDescrUtils/BinUtility.h"
// TrkGeometry
#include "TrkGeometry/LayerMaterialRecord.h"
#include "TrkGeometry/TrackingVolume.h"
#include "TrkGeometry/MaterialStep.h"
#include "TrkGeometry/MaterialProperties.h"
#include "TrkGeometry/AssociatedMaterial.h"
#include "TrkGeometry/LayerMaterialMap.h"
#include "TrkGeometry/LayerMaterialProperties.h"
#include "TrkGeometry/BinnedLayerMaterial.h"
#include "TrkGeometry/CompressedLayerMaterial.h"
#include "TrkGeometry/HomogeneousLayerMaterial.h"
// TrkEvent
#include "TrkNeutralParameters/NeutralParameters.h"
// Amg
#include "GeoPrimitives/GeoPrimitivesToStringConverter.h"
 
#ifdef TRKDETDESCR_MEMUSAGE
#include <unistd.h>
#endif
 
Trk::MaterialMapping::MaterialMapping(const std::string& name, ISvcLocator* pSvcLocator)
: AthAlgorithm(name,pSvcLocator),
  m_checkForEmptyHits(true),
  m_mappingVolumeName("Atlas"),
  m_mappingVolume(nullptr),
  m_inputMaterialStepCollection("MaterialStepRecords"),
  m_etaCutOff(6.0),
  m_etaSide(0),
  m_useLayerThickness(false),
  m_associationType(1),
  m_mapMaterial(true),
  m_mapComposition(false),
  m_minCompositionFraction(0.005),
  m_elementTable(nullptr),
  m_inputEventElementTable("ElementTable"),
  m_accumulatedMaterialXX0(0.),
  m_accumulatedRhoS(0.),
  m_mapped(0),
  m_unmapped(0),
  m_skippedOutside(0),
  m_layerMaterialScreenOutput(0)
#ifdef TRKDETDESCR_MEMUSAGE      
  ,m_memoryLogger()
#endif 
{
    // the name of the volume to map
    declareProperty("MappingVolumeName"           , m_mappingVolumeName);
    // the extrapolation engine
    declareProperty("CheckForEmptyHits"           , m_checkForEmptyHits);
    // general steering
    declareProperty("EtaCutOff"                   , m_etaCutOff);
    declareProperty("EtaSide"                     , m_etaSide);
    // the toolhandle of the MaterialMapper to be used
    declareProperty("MapMaterial"                 , m_mapMaterial);
    // Composition related parameters
    declareProperty("MapComposition"              , m_mapComposition);
    declareProperty("MinCompositionFraction"      , m_minCompositionFraction);
    // Steer the layer thickness
    declareProperty("UseActualLayerThicknesss"    , m_useLayerThickness);
    // some job setup
    declareProperty("MaterialAssociationType"     , m_associationType);
    declareProperty("InputMaterialStepCollection" , m_inputMaterialStepCollection);
    declareProperty("InputElementTable"           , m_inputEventElementTable);
    // Output screen stuff
    declareProperty("MaterialScreenOutputLevel"   , m_layerMaterialScreenOutput);
    
}
 
Trk::MaterialMapping::~MaterialMapping()
= default;
 
 
StatusCode Trk::MaterialMapping::initialize()
{
 
    ATH_MSG_INFO("initialize()");
 
    ATH_CHECK( m_trackingGeometryReadKey.initialize(!m_trackingGeometryReadKey.key().empty()) );
 
    ATH_CHECK(m_extrapolationEngine.retrieve());
 
    if ( !m_materialMapper.empty() )
      ATH_CHECK( m_materialMapper.retrieve() );
    
    if ( !m_layerMaterialRecordAnalyser.empty() ) 
      ATH_CHECK( m_layerMaterialRecordAnalyser.retrieve() );
        
    if ( !m_layerMaterialCreators.empty() )
      ATH_CHECK( m_layerMaterialCreators.retrieve() );
 
    if ( !m_layerMaterialAnalysers.empty() )
      ATH_CHECK( m_layerMaterialAnalysers.retrieve() );
 
    ATH_CHECK( m_inputMaterialStepCollection.initialize() );
    ATH_CHECK(  m_inputEventElementTable.initialize() );
        
    return StatusCode::SUCCESS;
}
 
 
StatusCode Trk::MaterialMapping::execute()
{
    ATH_MSG_VERBOSE("MaterialMapping execute() start");
 
    // ------------------------------- get the trackingGeometry at first place
    if (!m_mappingVolume) {
        StatusCode retrieveCode = handleTrackingGeometry();
        if (retrieveCode.isFailure()){
            ATH_MSG_INFO("Could not retrieve mapping volume from tracking geometry. Exiting.");
            return retrieveCode;
        }
    } 
    if (m_mappingVolume)
      ATH_MSG_VERBOSE("Mapping volume correctly retrieved from tracking geometry");  
    
    
    SG::ReadHandle<MaterialStepCollection> materialStepCollection(m_inputMaterialStepCollection);
    
        // --------- prepare the element table ---------------------------------------------------
 
    if (m_mapComposition) {
      SG::ReadHandle<Trk::ElementTable> eTableEvent(m_inputEventElementTable);
      (*m_elementTable) += (*eTableEvent);  // accummulate the table 
    }
    
    
    // event parameters - associated asteps, and layers hit per event
    int associatedSteps      = 0;
    m_accumulatedMaterialXX0 = 0.;
    m_accumulatedRhoS        = 0.;
    m_layersRecordedPerEvent.clear();
    // clearing the recorded layers per event
    if (materialStepCollection.isValid() && !materialStepCollection->empty()){
    
       // get the number of material steps 
       size_t materialSteps = materialStepCollection->size();
       ATH_MSG_DEBUG("[+] Successfully read  "<<  materialSteps << " geantino steps");
       
       // create a direction out of the last material step
       double dirx = (*materialStepCollection)[materialSteps-1]->hitX();
       double diry = (*materialStepCollection)[materialSteps-1]->hitY();
       double dirz = (*materialStepCollection)[materialSteps-1]->hitZ();
       Amg::Vector3D direction = Amg::Vector3D(dirx,diry,dirz).unit();
       
       double eta = direction.eta();
       // skip the event if the eta cut is not met
       if ( fabs(eta) > m_etaCutOff || (m_etaSide && m_etaSide*eta < 0.)  ) {
           ATH_MSG_VERBOSE("[-] Event is outside eta acceptance of " << m_etaCutOff << ". Skipping it.");
           return StatusCode::SUCCESS;
       }
       
       // now propagate through the full detector and collect the layers
       Trk::NeutralCurvilinearParameters ncP(Amg::Vector3D(0.,0.,0.), direction, 0.);
       // create a neutral extrapolation cell
       Trk::ExtrapolationCell<Trk::NeutralParameters> ecc(ncP);
       ecc.navigationCurvilinear = false;
       ecc.addConfigurationMode(Trk::ExtrapolationMode::StopAtBoundary);
       ecc.addConfigurationMode(Trk::ExtrapolationMode::CollectPassive);
       ecc.addConfigurationMode(Trk::ExtrapolationMode::CollectBoundary);
       
       // let's extrapolate through the detector and remember which layers (with material) should have been hit
       std::vector< std::pair<const Trk::Layer*, Amg::Vector3D> > layersAndHits;
       // call the extrapolation engine
       Trk::ExtrapolationCode eCode = m_extrapolationEngine->extrapolate(ecc);
       // end the parameters if there
       if (eCode.isSuccess()){
           // name of passive surfaces found
           size_t nLayersHit = ecc.extrapolationSteps.size();
           ATH_MSG_VERBOSE("[+] Extrapolation to layers did succeed and found " << nLayersHit << " layers.");
           // reserve the size of the vectors
           layersAndHits.reserve(nLayersHit);
           // for screen output
           size_t ilayer = 0;
           // find all the intersected material - remember the last parameters
           const Trk::NeutralParameters* parameters = nullptr; 
           // loop over the collected information
           for (auto& es : ecc.extrapolationSteps){
               // continue if we have parameters
              parameters = es.parameters;
              if (parameters){
                  const Trk::Surface& pSurface = parameters->associatedSurface();
                  // get the surface with associated layer (that has material)
                  ATH_MSG_VERBOSE("[L] Testing layer with associatedLayer() " << pSurface.associatedLayer() << " and materialLayer() " << pSurface.materialLayer() );
                  // 
                  if ( ( pSurface.associatedLayer() && pSurface.associatedLayer()->layerMaterialProperties() )  || pSurface.materialLayer() ){
                      // material layer 
                      const Trk::Layer* mLayer = pSurface.materialLayer() ? pSurface.materialLayer() : pSurface.associatedLayer();
                      // record that one
                      std::pair<const Trk::Layer*, Amg::Vector3D> layerHitPair(mLayer, parameters->position());
                      ATH_MSG_VERBOSE("[L] Layer " << ++ilayer << " with index " << mLayer->layerIndex().value() << " hit at " << Amg::toString(parameters->position()));
                      layersAndHits.push_back(layerHitPair);
                  }
                  delete parameters;
              }
            }
            // cleanup of the final hits
            if (ecc.endParameters != parameters) delete ecc.endParameters;
            
            // we have no layers and Hits
            if (layersAndHits.empty()){
                ATH_MSG_VERBOSE("[!] No Layer was intersected - skipping.");
                return StatusCode::SUCCESS;
            }
            
            // layers are ordered, hence you can move the starting point along
            size_t currentLayer = 0;
            // loop through hits and find the closest layer, the start point moves outwards as we go 
            for ( const Trk::MaterialStep* step : *materialStepCollection ) {
               // verbose output    
               ATH_MSG_VERBOSE("[L] starting from layer " << currentLayer << " from layer collection for this step.");
               // step length and position
               double t     = step->steplength();
               Amg::Vector3D pos(step->hitX(), step->hitY(), step->hitZ());
               // skip if : 
               // -- 0) no mapping volume exists
               // -- 1) outside the mapping volume 
               // -- 2) outside the eta acceptance
               if (!m_mappingVolume || !(m_mappingVolume->inside(pos)) || fabs(pos.eta()) > m_etaCutOff ){
                  ++m_skippedOutside;
                  continue;
               }
               // now find the closest layer
               // (a) if the currentLayer is the last layer and the hit is still inside -> assign
               if (currentLayer < nLayersHit-1) {
                   // search through the layers - this is the reference distance for projection
                   double currentDistance = (pos-layersAndHits[currentLayer].second).mag();
                   ATH_MSG_VERBOSE("- current distance is " << currentDistance << " from " << Amg::toString(pos) << " and " << Amg::toString(layersAndHits[currentLayer].second) );
                   for (size_t testLayer = (currentLayer+1); testLayer < nLayersHit; ++testLayer){
                       // calculate teh distance to the testLayer
                       double testDistance = (pos-layersAndHits[testLayer].second).mag();
                       ATH_MSG_VERBOSE("[L] Testing layer " << testLayer << " from layer collection for this step.");
                       ATH_MSG_VERBOSE("- test    distance is " << testDistance << " from " << Amg::toString(pos) << " and " << Amg::toString(layersAndHits[testLayer].second) );
                       if ( testDistance < currentDistance ){
                           // screen output
                           ATH_MSG_VERBOSE("[L] Skipping over to current layer " << testLayer << " because " << testDistance << " < " << currentDistance); 
                           // the test distance did shrink - update currentLayer
                           currentLayer      = testLayer; 
                           currentDistance   = testDistance;
                       } else {
                           // stick to the layer you have 
                           break;
                       }
                   }
               }
               // the currentLayer *should* be correct now 
               const Trk::Layer* assignedLayer =  layersAndHits[currentLayer].first;
               Amg::Vector3D assignedPosition  = layersAndHits[currentLayer].second;
               // associate the hit 
               // (1) count it 
               ++associatedSteps;
               // (2) associate it
               associateHit(*assignedLayer, pos, assignedPosition, t, step->fullMaterial());
          } // loop over material Steps
        
          // check for the empty hits - they need to be taken into account
          ATH_MSG_VERBOSE("Found " << layersAndHits.size() << " intersected layers - while having " << m_layersRecordedPerEvent.size() << " recorded ones.");
        
          // now - cross-chek if you have additional layers 
          for ( auto& lhp : layersAndHits){
              // check if you find the layer int he already done record-map : not found - we need to do an empty hit scaling
              if (m_layersRecordedPerEvent.find(lhp.first) == m_layersRecordedPerEvent.end()){
                  // try to find the layer material record
                  auto clIter = m_layerRecords.find(lhp.first);
                  if (clIter != m_layerRecords.end() ){
                      (*clIter).second.associateEmptyHit(lhp.second);
                      ATH_MSG_VERBOSE("- to layer with index "<< lhp.first->layerIndex().value() << " with empty hit detected.");
                  } else
                      ATH_MSG_WARNING("- no Layer found in the associated map! Should not happen.");
              }
           }
           
           // check whether the event was good for at least one hit
           if (associatedSteps) {
               ATH_MSG_VERBOSE("There are associated steps, need to call finalizeEvent() & record to the MaterialMapper.");
               // finalize the event   --------------------- Layers ---------------------------------------------
               for (auto& lRecord : m_layerRecords ) {
                   // associated material
                   Trk::AssociatedMaterial* assMatHit = lRecord.second.finalizeEvent((*lRecord.first));
                   // record the full layer hit 
                   if (assMatHit && !m_materialMapper.empty()) m_materialMapper->recordLayerHit(*assMatHit, true);
                   delete assMatHit;
                   // call the material mapper finalize method
                   ATH_MSG_VERBOSE("Calling finalizeEvent on the MaterialMapper ...");
               } 
           } // the event had at least one associated hit
 
        } // end of eCode.success : needed for new mapping schema  
     
     } // material steps existed
         
 
    return StatusCode::SUCCESS;
}
 
 
bool Trk::MaterialMapping::associateHit( const Trk::Layer& associatedLayer, 
                                         const Amg::Vector3D& pos,
                                         const Amg::Vector3D& positionOnLayer,
                                         double stepl,
                                         const Trk::Material& mat)
{   
    // get the intersection with the layer
    ++m_mapped;
    // get the layer
    const Trk::Layer* layer = &associatedLayer;
    
    // get the associated volume
    const Trk::TrackingVolume* associatedVolume = trackingGeometry().lowestTrackingVolume(pos);
    
    // try to find the layer material record
    auto clIter = m_layerRecords.find(layer);              
    if (clIter != m_layerRecords.end() ){
        // remember that you actually hit this layer
        m_layersRecordedPerEvent[layer] = true;
        // LayerMaterialRecord found, add the hit
        (*clIter).second.associateGeantinoHit(positionOnLayer, stepl, mat);           
        ATH_MSG_VERBOSE("- associate Geantino Information at intersection [r/z] = " << positionOnLayer.perp() << "/"<< positionOnLayer.z() );
        ATH_MSG_VERBOSE("                                      mapping distance = " << (pos-positionOnLayer).mag() );
        ATH_MSG_VERBOSE("- associate Geantino Information ( s, s/x0 , x0 , l0, a, z, rho ) = "
                            << stepl << ", "<< stepl/mat.X0 << ", "<< mat.X0 << ", "<< mat.L0 << ", "<< mat.A << ", "<<  mat.Z << ", "<< mat.rho );
        m_accumulatedMaterialXX0 += stepl/mat.X0;
        m_accumulatedRhoS += stepl*mat.rho;
        ATH_MSG_VERBOSE("- accumulated material information X/x0 = " << m_accumulatedMaterialXX0);
        ATH_MSG_VERBOSE("- accumulated effective densitity rho*s = " << m_accumulatedRhoS);
        ATH_MSG_VERBOSE("- to layer with index "<< layer->layerIndex().value() << " from '"<< associatedVolume->volumeName() << "'.");
        // record the plain information w/o correction & intersection
        if (m_mapMaterial && !m_materialMapper.empty()){
                Trk::AssociatedMaterial am(pos, stepl, mat, 1., associatedVolume, layer);
                m_materialMapper->recordMaterialHit(am, positionOnLayer);
                ATH_MSG_VERBOSE(" - associated material produced as : " << am);
            }
        
    } else if (layer) {
        ATH_MSG_WARNING("- associate hit - the layer with index " << layer->layerIndex().value() << " was not found - should not happen!");
    }
    // return 
    return true;
}
 
 
void Trk::MaterialMapping::assignLayerMaterialProperties( Trk::TrackingVolume& tvol,
                                                          Trk::LayerMaterialMap* propSet)
{
 
    if (!propSet) return;
 
    ATH_MSG_INFO("Processing TrackingVolume: "<< tvol.volumeName() );
 
    // ----------------------------------- loop over confined layers ------------------------------------------
    Trk::BinnedArray< Trk::Layer >* confinedLayers = tvol.confinedLayers();
    if (confinedLayers) {
        // get the objects in a vector-like format
        Trk::BinnedArraySpan<Trk::Layer * const> layers = confinedLayers->arrayObjects();
        ATH_MSG_INFO("--> found : "<< layers.size() << "confined Layers");
        // the iterator over the vector
        // loop over layers
        for (Trk::Layer* layer : layers) {
            // assign the material and output
            if (layer && (*layer).layerIndex().value() ) {
                ATH_MSG_INFO("  > LayerIndex: "<< (*layer).layerIndex() );
                // set the material!
                if (propSet) {
                    // find the pair
                    auto curIt = propSet->find((*layer).layerIndex());
                    if (curIt != propSet->end()) {
                        ATH_MSG_INFO("LayerMaterial assigned for Layer with index: "<< (*layer).layerIndex() );
                        // set it to the layer
                        layer->assignMaterialProperties(*((*curIt).second), 1.);
                    }
                }
            }
        }
    }
 
    // ----------------------------------- loop over confined volumes -----------------------------
    Trk::BinnedArray<Trk::TrackingVolume >* confinedVolumes = tvol.confinedVolumes();
    if (confinedVolumes) {
        // get the objects in a vector-like format
        Trk::BinnedArraySpan<Trk::TrackingVolume * const> volumes = confinedVolumes->arrayObjects();
        ATH_MSG_INFO("--> found : "<< volumes.size() << "confined TrackingVolumes");
        // loop over volumes
        for (const auto & volume : volumes) {
            // assing the material and output
            if (volume)
                assignLayerMaterialProperties(*volume, propSet); // call itself recursively
        }
    }
}
 
 
StatusCode Trk::MaterialMapping::finalize()
{
 
    ATH_MSG_INFO("========================================================================================= ");
    ATH_MSG_INFO("finalize() starts ...");
    
#ifdef TRKDETDESCR_MEMUSAGE       
    m_memoryLogger.refresh(getpid());
    ATH_MSG_INFO("[ memory usage ] Start building of material maps: " );    
    ATH_MSG_INFO( m_memoryLogger );                     
#endif  
        
    // create a dedicated LayerMaterialMap by layerMaterialCreator;
    std::map< std::string, Trk::LayerMaterialMap* > layerMaterialMaps;
    for (  auto& lmcIter : m_layerMaterialCreators  ){
        ATH_MSG_INFO("-> Creating material map '"<< lmcIter->layerMaterialName() << "' from creator "<<  lmcIter.typeAndName() );
        layerMaterialMaps[lmcIter->layerMaterialName()] = new Trk::LayerMaterialMap(); 
    }
    
    ATH_MSG_INFO( m_layerRecords.size() << " LayerMaterialRecords to be finalized for this material mapping run.");
    
    // loop over the layers and output the stuff --- fill the associatedLayerMaterialProperties
    for ( auto& lIter :  m_layerRecords ) {
        // Get the key map, the layer & the volume name
        const Trk::Layer*  layer = lIter.first;
        Trk::LayerIndex layerKey = layer->layerIndex();
        // get the enclosing tracking volume
        const Trk::TrackingVolume* eVolume = layer->enclosingTrackingVolume();
        // assign the string
        std::string vName = eVolume ? (eVolume->volumeName()) : " BoundaryCollection ";
        ATH_MSG_INFO("Finalize MaterialAssociation for Layer "<< layerKey.value() << " in " << vName );
        // normalize - use m_finalizeRunDebug
        (lIter.second).finalizeRun(m_mapComposition);
        // output the material to the analyser if registered
        if (!m_layerMaterialRecordAnalyser.empty() && m_layerMaterialRecordAnalyser->analyseLayerMaterial(*layer, lIter.second).isFailure() )
            ATH_MSG_WARNING("Could not analyse the LayerMaterialRecord  for layer "<< layerKey.value() );
        // check if we have analysers per creator
        bool analyse = (m_layerMaterialCreators.size() == m_layerMaterialAnalysers.size());
        // and now use the creators to make the maps out of the LayerMaterialRecord
        size_t ilmc = 0;
        for ( auto& lmcIter : m_layerMaterialCreators ){
            // call the creator and register in the according map
#ifdef TRKDETDESCR_MEMUSAGE       
            m_memoryLogger.refresh(getpid());
            ATH_MSG_INFO("[ memory usage ] Before building the map for Layer "<< layerKey.value()  );    
            ATH_MSG_INFO( m_memoryLogger );                     
#endif  
            const Trk::LayerMaterialProperties* lMaterial = lmcIter->createLayerMaterial(lIter.second);
#ifdef TRKDETDESCR_MEMUSAGE       
            m_memoryLogger.refresh(getpid());
            ATH_MSG_INFO("[ memory usage ] After building the map for Layer "<< layerKey.value()  );    
            ATH_MSG_INFO( m_memoryLogger );                     
#endif  
            if (lMaterial)
                ATH_MSG_VERBOSE("LayerMaterial map created as "<< *lMaterial );
            // insert the created map for the given layer
            (*layerMaterialMaps[lmcIter->layerMaterialName()])[layerKey.value()] = lMaterial;
            // analyse the it if configured
            if (analyse && lMaterial && (m_layerMaterialAnalysers[ilmc]->analyseLayerMaterial(*layer, *lMaterial)).isFailure() )
                ATH_MSG_WARNING("Could not analyse created LayerMaterialProperties for layer "<< layerKey.value() );
            ++ilmc;
        }
    }
 
    ATH_MSG_INFO("Finalize map synchronization and write the maps to the DetectorStore.");
   
    for (auto& ilmIter : layerMaterialMaps ){
      // elementTable handling - if existent
      if (m_mapComposition){
          Trk::SharedObject<const Trk::ElementTable> tElementTable(new Trk::ElementTable(*m_elementTable));
          ilmIter.second->updateElementTable(tElementTable);
          if (ilmIter.second->elementTable()){
              ATH_MSG_INFO("ElementTable for LayerMaterialMap '" << ilmIter.first << "' found and syncrhonized." );
              ATH_MSG_INFO( *(ilmIter.second->elementTable()) );
          }
      }
      // detector store writing        
      if ( (detStore()->record(ilmIter.second, ilmIter.first, false)).isFailure()){
          ATH_MSG_ERROR( "Writing of LayerMaterialMap with name '" << ilmIter.first << "' was not successful." );
          delete ilmIter.second;
      } else ATH_MSG_INFO( "LayerMaterialMap: " << ilmIter.first << " written to the DetectorStore!" );
    }
    delete m_elementTable;
 
#ifdef TRKDETDESCR_MEMUSAGE       
    m_memoryLogger.refresh(getpid());
    ATH_MSG_INFO( "[ memory usage ] At the end of the material map creation.");    
    ATH_MSG_INFO( m_memoryLogger );                     
#endif  
 
    ATH_MSG_INFO( "========================================================================================= " );
    ATH_MSG_INFO( "    ->  Total mapped hits                  : "  << m_mapped         );
    double unmapped = (m_unmapped+m_mapped) ? double(m_unmapped)/double(m_unmapped+m_mapped) : 0.;
    ATH_MSG_INFO( "    ->  Total (rel.) unmapped hits         : "  << m_unmapped << " (" <<  unmapped << ")" );
    ATH_MSG_INFO( "    ->  Skipped (outisde)                  : "  << m_skippedOutside );
    ATH_MSG_INFO( "========================================================================================= " );
    ATH_MSG_INFO( "finalize() successful");
    return StatusCode::SUCCESS;
}
 
 
StatusCode Trk::MaterialMapping::handleTrackingGeometry()
{
    // either get a string volume or the highest one
    const Trk::TrackingVolume* trackingVolume = trackingGeometry().highestTrackingVolume();
    
    // prepare the mapping volume
    m_mappingVolume = trackingGeometry().trackingVolume(m_mappingVolumeName);
    
    // register the confined layers from the TrackingVolume
    registerVolume(*trackingVolume, 0);
    
    ATH_MSG_INFO("Add "<< m_layerRecords.size() << " confined volume layers to mapping setup.");
    ATH_MSG_INFO("Add "<< trackingGeometry().numBoundaryLayers() << " boundary layers to mapping setup.");
    
    // register the layers from boundary surfaces
    for (const auto bLayerIter : trackingGeometry().boundaryLayers())
        insertLayerMaterialRecord(*(bLayerIter.first));
 
    ATH_MSG_INFO("Map for "<< m_layerRecords.size() << " layers booked & prepared for mapping procedure");
 
    return StatusCode::SUCCESS;
 
}
 
 
void Trk::MaterialMapping::registerVolume(const Trk::TrackingVolume& tvol, int lvl)
{
    int sublevel = lvl+1;
 
    for (int indent=0; indent<sublevel; ++indent)
        std::cout << " ";
    std::cout << "TrackingVolume name: "<< tvol.volumeName() << std::endl;
 
    // all those to be processed
    std::vector<const Trk::Layer*> volumeLayers;
  
    // collect all material layers that have layerMaterial
    const Trk::BinnedArray< Trk::Layer >* confinedLayers = tvol.confinedLayers();
    if (confinedLayers) {
         // this go ahead with the layers
         Trk::BinnedArraySpan<Trk::Layer const * const> layers = confinedLayers->arrayObjects();
         for (int indent=0; indent<sublevel; ++indent)
             std::cout << " ";
         std::cout << "- found : "<< layers.size() << "confined Layers"<< std::endl;
         // loop over and fill them
         auto clIter  = layers.begin();
         auto clIterE = layers.end();
         for ( ; clIter != clIterE; ++clIter ) {
            // only take layers with MaterialProperties defined and which are within the mapping volume
            const Amg::Vector3D& sReferencePoint = (*clIter)->surfaceRepresentation().globalReferencePoint(); 
            bool insideMappingVolume = m_mappingVolume ? m_mappingVolume->inside(sReferencePoint) : true;
            if ((*clIter)->layerMaterialProperties() && insideMappingVolume)
                volumeLayers.push_back((*clIter));
        }
    }        
    
   // now create LayerMaterialRecords for all
   for ( auto& lIter : volumeLayers )
           insertLayerMaterialRecord(*lIter);
   
    // step dopwn the navigation tree to reach the confined volumes
    const Trk::BinnedArray<Trk::TrackingVolume >* confinedVolumes = tvol.confinedVolumes();
    if (confinedVolumes) {
        Trk::BinnedArraySpan<Trk::TrackingVolume const * const> volumes = confinedVolumes->arrayObjects();
 
        for (int indent=0; indent<sublevel; ++indent)
            std::cout << " ";
        std::cout << "- found : "<< volumes.size() << "confined TrackingVolumes"<< std::endl;
        // loop over the confined volumes
        auto volumesIter = volumes.begin();
        for (; volumesIter != volumes.end(); ++volumesIter)
            if (*volumesIter) {
                registerVolume(**volumesIter, sublevel);
            }
    }
 
}
 
void Trk::MaterialMapping::insertLayerMaterialRecord(const Trk::Layer& lay){
 // first occurrance, create a new LayerMaterialRecord
 // - get the bin utility for the binned material (if necessary)
 // - get the material first
 const Trk::LayerMaterialProperties* layerMaterialProperties = lay.layerMaterialProperties();
 // - dynamic cast to the BinnedLayerMaterial
 const Trk::BinnedLayerMaterial* layerBinnedMaterial
 = dynamic_cast<const Trk::BinnedLayerMaterial*>(layerMaterialProperties);
 // get the binned array
 const Trk::BinUtility* layerMaterialBinUtility = (layerBinnedMaterial) ? layerBinnedMaterial->binUtility() : nullptr;
 // now fill the layer material record
 if (layerMaterialBinUtility){
     // create a new Layer Material record in the map
     Trk::LayerMaterialRecord  lmr((m_useLayerThickness ? lay.thickness() : 1.),
                                   layerMaterialBinUtility,
                                   (Trk::MaterialAssociationType)m_associationType);
     // and fill it into the map
     m_layerRecords[&lay] = lmr;                        
 }
}
 
void Trk::MaterialMapping::throwFailedToGetTrackingGeometry() const {
   std::stringstream msg;
   msg << "Failed to get conditions data " << m_trackingGeometryReadKey.key() << ".";
   throw std::runtime_error(msg.str());
}