ZPlanarTracker_geo.cpp

Go to the documentation of this file. Or view the newest version in sPHENIX GitHub for file ZPlanarTracker_geo.cpp

// This file is part of the Acts project.
//
// Copyright (C) 2017 CERN for the benefit of the Acts project
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

// This DD4hep Constructor is closely inspred from
// https://github.com/AIDASoft/DD4hep/tree/master/examples/SimpleDetector

// $Id: $
//====================================================================
//  Simple tracking detector made from planar sensors that are parallel
//  to the z-axis. There are two materials per ladder: one sensitive
//  and one support.
//--------------------------------------------------------------------
//
//  Author     : F.Gaede
//
//====================================================================
#include <exception>

#include "DD4hep/DetFactoryHelper.h"
//#include "DDRec/DetectorData.h"
//#include "DDRec/Surface.h"

using namespace dd4hep;
// using namespace DD4hep::DDRec;
// using namespace DDSurfaces;

#include "Acts/Plugins/DD4hep/ActsExtension.hpp"
#include "Acts/Utilities/Units.hpp"

static Ref_t create_element(Detector& lcdd, xml_h e, SensitiveDetector sens) {
  xml_det_t x_det = e;
  std::string name = x_det.nameStr();

  // put the whole detector into an assembly
  //  - should be replaced by an envelope volume ...

  Assembly assembly(name + "_assembly");

  DetElement tracker(name, x_det.id());

  // add Extension to Detlement for the RecoGeometry of ACTS
  Acts::ActsExtension* detvolume = new Acts::ActsExtension();
  detvolume->addType("barrel", "detector");
  tracker.addExtension<Acts::ActsExtension>(detvolume);

  PlacedVolume pv;

  // DDRec::ZPlanarData* zPlanarData = new DDRec::ZPlanarData;

  double minRadius = 1e99;
  double minZhalf = 1e99;

  //=========  loop over layer elements in xml
  //======================================

  for (xml_coll_t c(e, _U(layer)); c; ++c) {
    xml_comp_t x_layer(c);

    // child elements: ladder and sensitive
    xml_comp_t x_sensitive(x_layer.child(_U(sensitive)));
    xml_comp_t x_ladder(x_layer.child(_U(ladder)));

    int layer_id = x_layer.id();
    int nLadders = x_layer.attr<double>(_Unicode(nLadders));

    double dphi = 2. * M_PI / double(nLadders);

    std::string layername = name + _toString(layer_id, "_layer%d");

    // --- create an assembly and DetElement for the layer

    Assembly layer_assembly("layer_assembly" + _toString(layer_id, "_%d"));

    DetElement layerDE(tracker, _toString(layer_id, "layer_%d"), x_det.id());

    // add Extension for translation to ACTS TrackingGeometry
    Acts::ActsExtension* detlayer = new Acts::ActsExtension("zyx");
    detlayer->addValue(10. * Acts::UnitConstants::mm, "r", "envelope");
    detlayer->addValue(10. * Acts::UnitConstants::mm, "z", "envelope");
    detlayer->addType("sensitive plane", "layer");
    layerDE.addExtension<Acts::ActsExtension>(detlayer);

    pv = assembly.placeVolume(layer_assembly);

    pv.addPhysVolID("layer", layer_id);

    layerDE.setPlacement(pv);

    //--------------------------------

    double supp_zhalf = x_ladder.length();
    double supp_offset = x_ladder.offset();
    double supp_distance = x_ladder.distance();
    double supp_thickness = x_ladder.thickness();
    double supp_width = x_ladder.width();

    std::string supp_vis = x_ladder.visStr();
    std::string supp_matS = x_ladder.materialStr();

    double sens_zhalf = x_sensitive.length();
    double sens_offset = x_sensitive.offset();
    double sens_distance = x_sensitive.distance();
    double sens_thickness = x_sensitive.thickness();
    double sens_width = x_sensitive.width();

    std::string sens_view = x_sensitive.visStr();
    std::string sens_matS = x_sensitive.materialStr();

    double phi0 = x_layer.phi0();

    if (sens_distance < minRadius)
      minRadius = sens_distance;
    if (supp_distance < minRadius)
      minRadius = supp_distance;
    if (sens_zhalf < minZhalf)
      minZhalf = sens_zhalf;
    if (supp_zhalf < minZhalf)
      minZhalf = supp_zhalf;

    //-----------------------------------
    //  store the data in an extension to be used for reconstruction
    /*   DDRec::ZPlanarData::LayerLayout thisLayer;

        thisLayer.sensorsPerLadder = 1;  // for now only one planar sensor
        thisLayer.lengthSensor     = 2. * sens_zhalf;

        thisLayer.distanceSupport  = supp_distance;
        thisLayer.offsetSupport    = supp_offset;
        thisLayer.thicknessSupport = supp_thickness;
        thisLayer.zHalfSupport     = supp_zhalf;
        thisLayer.widthSupport     = supp_width;

        thisLayer.distanceSensitive  = sens_distance;
        thisLayer.offsetSensitive    = sens_offset;
        thisLayer.thicknessSensitive = sens_thickness;
        thisLayer.zHalfSensitive     = sens_zhalf;
        thisLayer.widthSensitive     = sens_width;

        thisLayer.ladderNumber = nLadders;
        thisLayer.phi0         = phi0;

        zPlanarData->layers.push_back(thisLayer);*/
    //-----------------------------------

    Material supp_mat = lcdd.material(supp_matS);
    Material sens_mat = lcdd.material(sens_matS);

    //-------
    Box sens_box(sens_thickness / 2., sens_width / 2., sens_zhalf);
    Box supp_box(supp_thickness / 2., supp_width / 2., supp_zhalf);

    Volume supp_vol(layername + "_supp", supp_box, supp_mat);
    Volume sens_vol(layername + "_sens", sens_box, sens_mat);

    // -------- create a measurement plane for the tracking surface attched to
    // the sensitive volume -----
    /*    Vector3D u(0., 1., 0.);
        Vector3D v(0., 0., 1.);
        Vector3D n(1., 0., 0.);
        //    Vector3D o( 0. , 0. , 0. ) ;

        // compute the inner and outer thicknesses that need to be assigned to
       the
        // tracking surface
        // depending on wether the support is above or below the sensor
        double inner_thickness
            = (sens_distance > supp_distance
                   ? (sens_distance - supp_distance) + sens_thickness / 2
                   : sens_thickness / 2);
        double outer_thickness
            = (sens_distance > supp_distance
                   ? sens_thickness / 2
                   : (supp_distance - sens_distance) + supp_thickness
                       - sens_thickness / 2);

        SurfaceType type(SurfaceType::Sensitive);

        if (isStripDetector) type.setProperty(SurfaceType::Measurement1D, true);

        VolPlane surf(
            sens_vol, type, inner_thickness, outer_thickness, u, v, n);  //,o )
       ;
    */
    //--------------------------------------------

    sens.setType("tracker");
    sens_vol.setSensitiveDetector(sens);

    sens_vol.setAttributes(lcdd, x_det.regionStr(), x_det.limitsStr(),
                           sens_view);
    supp_vol.setAttributes(lcdd, x_det.regionStr(), x_det.limitsStr(),
                           supp_vis);

    //--------- loop over ladders ---------------------------

    for (int j = 0; j < nLadders; ++j) {
      double phi = phi0 + j * dphi;

      std::string laddername = layername + _toString(j, "_ladder%d");

      RotationZYX rot(phi, 0, 0);

      // --- place support -----
      double lthick = supp_thickness;
      double radius = supp_distance;
      double offset = supp_offset;

      /* pv = */ layer_assembly.placeVolume(
          supp_vol,
          Transform3D(
              rot,
              Position((radius + lthick / 2.) * cos(phi) - offset * sin(phi),
                       (radius + lthick / 2.) * sin(phi) + offset * cos(phi),
                       0.)));

      // --- place sensitive -----
      lthick = sens_thickness;
      radius = sens_distance;
      offset = sens_offset;

      pv = layer_assembly.placeVolume(
          sens_vol,
          Transform3D(
              rot,
              Position((radius + lthick / 2.0) * cos(phi) - offset * sin(phi),
                       (radius + lthick / 2.0) * sin(phi) + offset * cos(phi),
                       0.)));

      //      pv.addPhysVolID("layer", layer_id ).addPhysVolID( "module" , j
      //      ).addPhysVolID("sensor", 0 )   ;
      pv.addPhysVolID("module", j).addPhysVolID("sensor", 0);

      DetElement ladderDE(layerDE, laddername, x_det.id());
      ladderDE.setPlacement(pv);

      //      volSurfaceList(ladderDE)->push_back(surf);
    }

    //    tracker.setVisAttributes(lcdd, x_det.visStr(),laddervol);

    // is this needed ??
    layer_assembly->GetShape()->ComputeBBox();
  }

#if 0  //-------- add an inscribing cylinder of air for tracking purposes
       //-----------------
       //  this screw up the geometry and the material scan does not work
       //  anymore !!!!!?????

 /* double tube_thick =  1.0 * dd4hep::mm ;
  double inner_r    =  minRadius - 1.1 * tube_thick ;
  double outer_r    =  inner_r + tube_thick ;
  double z_half     =  minZhalf ;

  Tube   tubeSolid (inner_r, outer_r, z_half ) ;
  Volume tube_vol( name+"_inner_cylinder_air", tubeSolid ,  lcdd.material("Air") ) ;

  assembly.placeVolume( tube_vol , Transform3D() ) ;

  Vector3D ocyl(  inner_r + 0.5*tube_thick , 0. , 0. ) ;

  VolCylinder cylSurf( tube_vol , SurfaceType( SurfaceType::Helper ) , 0.5*tube_thick  , 0.5*tube_thick , ocyl ) ;

  volSurfaceList( tracker )->push_back( cylSurf ) ;*/

#endif  //----------------------------------------------------------------------------------

  //  tracker.addExtension<DDRec::ZPlanarData>(zPlanarData);

  Volume mother = lcdd.pickMotherVolume(tracker);

  pv = mother.placeVolume(assembly);

  pv.addPhysVolID("system", x_det.id()).addPhysVolID("side", 0);

  tracker.setPlacement(pv);

  assembly->GetShape()->ComputeBBox();

  return tracker;
}

DECLARE_DETELEMENT(ZPlanarTracker, create_element)