Merge pull request #38452 from mkirsano/hepmc3-addp8plugin

Add to Pythia8Interface the plugin that uses HepMC3

GeneratorInterface/Pythia8Interface/BuildFile.xml

@@ -8,6 +8,7 @@
 <use name="pythia8"/>
 <use name="evtgen"/>
 <use name="hepmc"/>
+<use name="hepmc3"/>
 <use name="clhep"/>
 <use name="root"/>
 <export>

GeneratorInterface/Pythia8Interface/interface/Py8HMC3InterfaceBase.h

@@ -0,0 +1,68 @@
+#ifndef gen_Py8HMC3InterfaceBase_h
+#define gen_Py8HMC3InterfaceBase_h
+
+#include <vector>
+#include <string>
+
+#include "GeneratorInterface/Core/interface/ParameterCollector.h"
+#include "GeneratorInterface/Pythia8Interface/interface/P8RndmEngine.h"
+#include "GeneratorInterface/Core/interface/BaseHadronizer.h"
+
+#include <Pythia8/Pythia.h>
+#include <Pythia8Plugins/HepMC3.h>
+
+namespace Pythia8 {
+  class EvtGenDecays;
+}
+
+namespace CLHEP {
+  class HepRandomEngine;
+}
+
+namespace gen {
+
+  class Py8HMC3InterfaceBase : public BaseHadronizer {
+  public:
+    Py8HMC3InterfaceBase(edm::ParameterSet const& ps);
+    ~Py8HMC3InterfaceBase() override = default;
+
+    virtual bool generatePartonsAndHadronize() = 0;
+    bool decay() { return true; }          // NOT used - let's call it "design imperfection"
+    bool readSettings(int);                // common func
+    void makeTmpSLHA(const std::string&);  //helper for above
+    virtual bool initializeForInternalPartons() = 0;
+    bool declareStableParticles(const std::vector<int>&);          // common func
+    bool declareSpecialSettings(const std::vector<std::string>&);  // common func
+    virtual void finalizeEvent() = 0;
+    virtual void statistics();
+    virtual const char* classname() const = 0;
+
+    void p8SetRandomEngine(CLHEP::HepRandomEngine* v) { p8RndmEngine_.setRandomEngine(v); }
+    P8RndmEngine& randomEngine() { return p8RndmEngine_; }
+
+  protected:
+    std::unique_ptr<Pythia8::Pythia> fMasterGen;
+    std::unique_ptr<Pythia8::Pythia> fDecayer;
+    HepMC3::Pythia8ToHepMC3 toHepMC;
+    edm::ParameterSet fParameters;
+
+    unsigned int pythiaPylistVerbosity;
+    bool pythiaHepMCVerbosity;
+    bool pythiaHepMCVerbosityParticles;
+    unsigned int maxEventsToPrint;
+
+    // EvtGen plugin
+    //
+    bool useEvtGen;
+    std::shared_ptr<Pythia8::EvtGenDecays> evtgenDecays;
+    std::string evtgenDecFile;
+    std::string evtgenPdlFile;
+    std::vector<std::string> evtgenUserFiles;
+
+    std::string slhafile_;
+
+  private:
+    P8RndmEngine p8RndmEngine_;
+  };
+}  // namespace gen
+#endif

GeneratorInterface/Pythia8Interface/plugins/BuildFile.xml

@@ -14,6 +14,21 @@
   <flags EDM_PLUGIN="1"/>
 </library>
 
+<library file="Pythia8HepMC3Hadronizer.cc,Py8toJetInput.cc,*Hook*.cc,LHA*.cc" name="GeneratorInterfacePythia8HepMC3Filters">
+  <use name="GeneratorInterface/PartonShowerVeto"/>
+  <use name="GeneratorInterface/ExternalDecays"/>
+  <use name="FWCore/Concurrency"/>
+  <use name="FWCore/MessageLogger"/>
+  <use name="FWCore/ParameterSet"/>
+  <use name="FWCore/ServiceRegistry"/>
+  <use name="FWCore/Utilities"/>
+  <use name="GeneratorInterface/Core"/>
+  <use name="hepmc3"/>
+  <use name="pythia8"/>
+  <use name="SimDataFormats/GeneratorProducts"/>
+  <flags EDM_PLUGIN="1"/>
+</library>
+
 <library file="Py*Gun.cc" name="GeneratorInterfacePythia8Guns">
   <use name="GeneratorInterface/ExternalDecays"/>
   <flags EDM_PLUGIN="1"/>

GeneratorInterface/Pythia8Interface/plugins/LHAupLesHouches.h

@@ -11,7 +11,7 @@
 
 #include "Pythia8/Pythia.h"
 #include "Pythia8/LesHouches.h"
-#include "Pythia8Plugins/HepMC2.h"
+//#include "Pythia8Plugins/HepMC2.h"
 
 #include "SimDataFormats/GeneratorProducts/interface/LesHouches.h"
 #include "GeneratorInterface/LHEInterface/interface/LHERunInfo.h"

GeneratorInterface/Pythia8Interface/plugins/Pythia8Hadronizer.cc

@@ -185,6 +185,7 @@ Pythia8Hadronizer::Pythia8Hadronizer(const edm::ParameterSet &params)
       nMEFiltered(-1),
       nISRveto(0),
       nFSRveto(0) {
+  ivhepmc = 2;
   // J.Y.: the following 3 parameters are hacked "for a reason"
   //
   if (params.exists("PPbarInitialState")) {