BDSCavityFactoryPillBox.cc

/* 
Beam Delivery Simulation (BDSIM) Copyright (C) Royal Holloway, 
University of London 2001 - 2023.
 
This file is part of BDSIM.
 
BDSIM is free software: you can redistribute it and/or modify 
it under the terms of the GNU General Public License as published 
by the Free Software Foundation version 3 of the License.
 
BDSIM is distributed in the hope that it will be useful, but 
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
 
You should have received a copy of the GNU General Public License
along with BDSIM.  If not, see <http://www.gnu.org/licenses/>.
*/
#include "BDSCavity.hh"
#include "BDSCavityFactoryPillBox.hh"
#include "BDSCavityInfo.hh"
 
#include "globals.hh"
#include "G4LogicalVolume.hh"
#include "G4SubtractionSolid.hh"
#include "G4Tubs.hh"
#include "G4UnionSolid.hh"
#include "G4VSolid.hh"
 
#include "CLHEP/Units/SystemOfUnits.h"
 
#include <set>
 
BDSCavityFactoryPillBox::BDSCavityFactoryPillBox()
{;}
 
BDSCavityFactoryPillBox::~BDSCavityFactoryPillBox()
{;}
 
G4double BDSCavityFactoryPillBox::CreateSolids(G4String             name,
                                               G4double             totalChordLength,
                                               const BDSCavityInfo* info)
{
  G4double chordLength  = totalChordLength;
  G4double cavityRadius = info->equatorRadius;
  G4VSolid* outerSolid = new G4Tubs(name + "_outer_solid",          // name
                                    info->irisRadius,               // inner radius
                                    cavityRadius + info->thickness, // outer radius
                                    0.5*chordLength - lengthSafety, // half length
                                    0.0,                            // start angle
                                    CLHEP::twopi);                  // sweep angle
  allSolids.insert(outerSolid);
   
  // creates a cylinder  to subtract from larger cylinder. 
  G4VSolid* innerSolid = new G4Tubs(name + "_inner_solid",            // name
                                    0.0,                              // inner radius 
                                    cavityRadius,                     // outer radius
                                    0.5*chordLength - info->thickness,// half length
                                    0.0,                              // star angle
                                    CLHEP::twopi);                    // sweep angle
  allSolids.insert(innerSolid);
  
  // subtraction
  cavitySolid = new G4SubtractionSolid(name + "_cavity_solid",    //name
                                       outerSolid,                //solid1
                                       innerSolid);               //minus solid2
  allSolids.insert(cavitySolid);
  
  // vacuum: union of two solid - one cylinder (VacuumInnerCavity) to fill the centre,
  // and a longer, thinner cylinder (vacuumAperture) to fill the ends provided by the thickness.
  G4double vacuumInnerRadius = cavityRadius - info->thickness - lengthSafety;
  G4double vacuumHalfLength  = 0.5*chordLength - info->thickness - lengthSafety;
  G4VSolid* vacuumInnerCavity = new G4Tubs(name + "_vacuum_inner_cavity_solid",// name
                                           0.0,                                // inner radius
                                           vacuumInnerRadius,                  // outer radius
                                           vacuumHalfLength,                   // half length
                                           0.0,                                // start angle
                                           CLHEP::twopi);                      // sweep angle
 
  G4VSolid* vacuumAperture = new G4Tubs(name + "_vacuum_aperture_solid",   // name
                                        0.0,                               // inner radius
                                        info->irisRadius - lengthSafety,   // outer radius
                                        0.5*chordLength - lengthSafety,    // half length
                                        0.0,                               // start angle
                                        CLHEP::twopi);                     // sweep angle
  
  // create the vacuum as a union of the two solides defined prior
  vacuumSolid = new G4UnionSolid(name + "_vacuum_solid",  // name
                                 vacuumInnerCavity,       // solid one
                                 vacuumAperture);         // added to solid two.
  allSolids.insert(vacuumInnerCavity);
  allSolids.insert(vacuumAperture);
  allSolids.insert(vacuumSolid);
 
  G4double containerRadius = cavityRadius + info->thickness + lengthSafety;
  containerSolid = new G4Tubs(name + "_container_solid",   // name
                              0.0,                         // innerRadius
                              containerRadius,             // outerRadius
                              chordLength*0.5,             // half length
                              0.0,                         // starting angle
                              CLHEP::twopi);               // sweep angle
  return containerRadius;
}