epic/src/LumiCollimator_geo.cpp

0001 // SPDX-License-Identifier: LGPL-3.0-or-later
0002 // Copyright (C) 2022 Justin Chan
0003
0004 //==========================================================================
0005 //
0006 // Places a collimator along the beam line
0007 //
0008 //==========================================================================
0009
0010 #include "DD4hep/DetFactoryHelper.h"
0011 #include <XML/Helper.h>
0012
0013 using namespace std;
0014 using namespace dd4hep;
0015
0016 static Ref_t create_detector(Detector& description, xml_h e, SensitiveDetector /* sens */) {
0017
0018   using namespace ROOT::Math;
0019   xml_det_t x_det = e;
0020   string det_name = x_det.nameStr();
0021   DetElement sdet(det_name, x_det.id());
0022   Assembly assembly(det_name + "_assembly");
0023   Material m_Steel = description.material("StainlessSteel");
0024   string vis_name  = x_det.visStr();
0025
0026   // Create outer box
0027   xml::Component box_dim = x_det.child(_Unicode(dimensions_outer));
0028   double height          = box_dim.attr<double>(_Unicode(y));
0029   double width           = box_dim.attr<double>(_Unicode(x));
0030   double depth           = box_dim.attr<double>(_Unicode(z));
0031
0032   Box box_outer(width, height, depth);
0033
0034   // Create inner box
0035   xml::Component box_dim_2 = x_det.child(_Unicode(dimensions_inner));
0036   double height_2          = box_dim_2.attr<double>(_Unicode(y));
0037   double width_2           = box_dim_2.attr<double>(_Unicode(x));
0038   double depth_2           = box_dim_2.attr<double>(_Unicode(z));
0039
0040   Box box_inner(width_2, height_2, depth_2);
0041
0042   // Sets box positions
0043   xml::Component box_pos = x_det.child(_Unicode(position));
0044   double x               = box_pos.attr<double>(_Unicode(x));
0045   double y               = box_pos.attr<double>(_Unicode(y));
0046   double z               = box_pos.attr<double>(_Unicode(z));
0047
0048   // Subtractes the volume of the inner box from the outer box
0049   BooleanSolid collimator = SubtractionSolid(box_outer, box_inner);
0050
0051   // Assembles the collimator and sets its material
0052   Volume v_collimator(det_name + "_vol_collimator", collimator, m_Steel);
0053
0054   sdet.setAttributes(description, v_collimator, x_det.regionStr(), x_det.limitsStr(), vis_name);
0055
0056   assembly.placeVolume(v_collimator, Position(x, y, z));
0057
0058   // Final placement
0059   auto pv_assembly = description.pickMotherVolume(sdet).placeVolume(
0060       assembly, Transform3D(RotationZYX(0.0, 0.0, 0.0), Position(0, 0, 0)));
0061
0062   sdet.setPlacement(pv_assembly);
0063
0064   assembly->GetShape()->ComputeBBox();
0065
0066   return sdet;
0067 }
0068
0069 DECLARE_DETELEMENT(LumiCollimator, create_detector)