DDG4/src/Geant4ParticleGun.cpp

0001 //==========================================================================
0002 //  AIDA Detector description implementation
0003 //--------------------------------------------------------------------------
0004 // Copyright (C) Organisation europeenne pour la Recherche nucleaire (CERN)
0005 // All rights reserved.
0006 //
0007 // For the licensing terms see $DD4hepINSTALL/LICENSE.
0008 // For the list of contributors see $DD4hepINSTALL/doc/CREDITS.
0009 //
0010 // Author     : M.Frank
0011 //
0012 //==========================================================================
0013
0014 // Framework include files
0015 #include <DD4hep/Printout.h>
0016 #include <DD4hep/InstanceCount.h>
0017 #include <DDG4/Geant4Context.h>
0018 #include <DDG4/Geant4Primary.h>
0019 #include <DDG4/Geant4ParticleGun.h>
0020 #include <DDG4/Geant4InputHandling.h>
0021 #include <CLHEP/Units/SystemOfUnits.h>
0022
0023 // C/C++ include files
0024 #include <limits>
0025
0026 using namespace dd4hep::sim;
0027
0028 /// Standard constructor
0029 Geant4ParticleGun::Geant4ParticleGun(Geant4Context* ctxt, const std::string& nam)
0030   : Geant4IsotropeGenerator(ctxt,nam), m_shotNo(0)
0031 {
0032   InstanceCount::increment(this);
0033   m_needsControl = true;
0034   declareProperty("Standalone",   m_standalone = true);
0035   declareProperty("mask",         m_mask);
0036   declareProperty("isotrop",      m_isotrop = false);
0037   declareProperty("standalone",   m_standalone);
0038   // Backwards compatibility: Un-capitalize
0039   declareProperty("position",     m_position);
0040   declareProperty("distribution", m_distribution);
0041   declareProperty("direction",    m_direction);
0042   declareProperty("particle",     m_particleName);
0043   declareProperty("multiplicity", m_multiplicity);
0044   declareProperty("print",        m_print = true);
0045 }
0046
0047 /// Default destructor
0048 Geant4ParticleGun::~Geant4ParticleGun() {
0049   InstanceCount::decrement(this);
0050 }
0051
0052 /// Particle modification. Caller presets defaults to: ( direction = m_direction, momentum = [mMin, mMax])
0053 void Geant4ParticleGun::getParticleDirection(int num, ROOT::Math::XYZVector& direction, double& momentum) const  {
0054   ( m_isotrop )
0055     ? this->Geant4IsotropeGenerator::getParticleDirection(num, direction, momentum)
0056     : this->Geant4ParticleGenerator::getParticleDirection(num, direction, momentum);
0057 }
0058
0059 /// Callback to generate primary particles
0060 void Geant4ParticleGun::operator()(G4Event* event)   {
0061   double r = m_direction.R(), eps = std::numeric_limits<float>::epsilon();
0062   if ( r > eps )  {
0063     m_direction.SetXYZ(m_direction.X()/r, m_direction.Y()/r, m_direction.Z()/r);
0064   }
0065
0066   if ( m_standalone )  {
0067     generationInitialization(this,context());
0068   }
0069
0070   //bit wasteful to always set this :(
0071   if( m_energy != -1 ){
0072     m_momentumMin = m_energy;
0073     m_momentumMax = m_energy;
0074   }
0075
0076   print("Shoot [%d] [%.3f , %.3f] GeV %s pos:(%.3f %.3f %.3f)[mm] dir:(%6.3f %6.3f %6.3f)",
0077         m_shotNo, m_momentumMin/CLHEP::GeV, m_momentumMax/CLHEP::GeV, m_particleName.c_str(),
0078         m_position.X()/CLHEP::mm, m_position.Y()/CLHEP::mm, m_position.Z()/CLHEP::mm,
0079         m_direction.X(), m_direction.Y(), m_direction.Z());
0080   this->Geant4ParticleGenerator::operator()(event);
0081   if ( m_print )   {
0082     this->Geant4ParticleGenerator::printInteraction(m_mask);
0083   }
0084   ++m_shotNo;
0085   if ( m_standalone ) {
0086     mergeInteractions(this,context());
0087     generatePrimaries(this,context(),event);
0088   }
0089 }