GenParticle.h

// -*- C++ -*-
//
// This file is part of HepMC
// Copyright (C) 2014-2023 The HepMC collaboration (see AUTHORS for details)
//
#ifndef HEPMC3_GENPARTICLE_H
#define HEPMC3_GENPARTICLE_H
#include <string>
#include "HepMC3/Data/GenParticleData.h"
#include "HepMC3/FourVector.h"
 
#include "HepMC3/GenParticle_fwd.h"
#include "HepMC3/GenVertex_fwd.h"
 
#ifdef HEPMC3_PROTOBUFIO
namespace HepMC3_pb {
class GenEventData_GenParticleData;
}
#endif
 
namespace HepMC3 {
 
class GenEvent;
class Attribute;
 
class GenParticle : public std::enable_shared_from_this<GenParticle> {
 
    friend class GenVertex;
    friend class GenEvent;
 
//
// Constructors
//
public:

    GenParticle( const FourVector &momentum = FourVector::ZERO_VECTOR(), int pid = 0, int status = 0 );

    GenParticle( const GenParticleData &data );
 
#ifdef HEPMC3_PROTOBUFIO
    GenParticle( HepMC3_pb::GenEventData_GenParticleData const &data );
#endif
 
//
// Functions
//
public:
    bool in_event() const { return (bool) (m_event); }

    GenEvent* parent_event() { return m_event; }
    const GenEvent* parent_event() const { return m_event; }

    int id() const { return m_id; }
 
    const GenParticleData& data()         const { return m_data;  } 
 
    ConstGenVertexPtr production_vertex() const;        
    ConstGenVertexPtr end_vertex() const;               
 
    GenVertexPtr production_vertex();        
    GenVertexPtr end_vertex();               

    std::vector<GenParticlePtr> parents();

    std::vector<ConstGenParticlePtr> parents() const;

    std::vector<GenParticlePtr> children();

    std::vector<ConstGenParticlePtr> children() const;
 
    int   pid()                   const { return m_data.pid;            } 
    int   abs_pid()               const { return std::abs(pid());            } 
    int   status()                const { return m_data.status;         } 
    const FourVector& momentum()  const { return m_data.momentum;       } 
    bool  is_generated_mass_set() const { return m_data.is_mass_set;    } 

    double generated_mass() const;
 
 
    void set_pid(int pid);                         
    void set_status(int status);                   
    void set_momentum(const FourVector& momentum); 
    void set_generated_mass(double m);             
    void unset_generated_mass();                   

    bool add_attribute(const std::string& name, std::shared_ptr<Attribute> att);

    std::vector<std::string> attribute_names() const;

    void remove_attribute(const std::string& name);

    template<class T>
    std::shared_ptr<T> attribute(const std::string& name) const;

    std::string attribute_as_string(const std::string& name) const;
 


    int pdg_id() const { return pid(); }

    void set_pdg_id(const int& pidin) { set_pid(pidin); }

//
// Fields
//
private:
    GenEvent        *m_event; 
    int              m_id;    
    GenParticleData  m_data;  
 
    std::weak_ptr<GenVertex>    m_production_vertex; 
    std::weak_ptr<GenVertex>    m_end_vertex;        
};
 
} // namespace HepMC3
 
 
 
#include "HepMC3/GenEvent.h"
namespace HepMC3 {
template<class T> std::shared_ptr<T> GenParticle::attribute(const std::string& name) const {
    return parent_event()?
           parent_event()->attribute<T>(name, id()): std::shared_ptr<T>();
}
}
#endif