WIP: add user track info to record the extra information of track.

Simulation/DetSimInterface/CMakeLists.txt

@@ -5,6 +5,7 @@
 gaudi_add_library(DetSimInterface
                  SOURCES src/IDetSimSvc.cpp
                          src/CommonUserEventInfo.cc
+                         src/CommonUserTrackInfo.cc
                  LINK Gaudi::GaudiKernel
                       ${Geant4_LIBRARIES}
 )

Simulation/DetSimInterface/include/DetSimInterface/CommonUserTrackInfo.hh

+#ifndef CommonUserTrackInfo_hh
+#define CommonUserTrackInfo_hh
+
+/* Description:
+ *   This class is a part of simulation framework to extend the G4Track.
+ *
+ *   Some secondaries are created due to decay. However, their G4 Track IDs are
+ *   not valid until the tracks are tracking by geant4. In order to associate
+ *   these tracks and their edm4hep MC particle, we use the track information
+ *   to record the extra track information.
+ *
+ * Author:
+ *   Tao Lin <lintao AT ihep.ac.cn>
+ */
+
+#include "G4VUserTrackInformation.hh"
+
+class CommonUserTrackInfo: public G4VUserTrackInformation {
+public:
+    CommonUserTrackInfo();
+    ~CommonUserTrackInfo();
+
+public:
+
+    virtual void Print() const;
+
+    // get the idx in the EDM4hep MC particle collection
+    bool setIdxEdm4hep(int idxEdm4hep);
+    int idxEdm4hep() const;
+
+private:
+    int m_idxEdm4hep = -1;
+};
+
+#endif

Simulation/DetSimInterface/src/CommonUserTrackInfo.cc

+#include "DetSimInterface/CommonUserTrackInfo.hh"
+#include <iostream>
+
+CommonUserTrackInfo::CommonUserTrackInfo() {
+
+}
+
+CommonUserTrackInfo::~CommonUserTrackInfo() {
+
+}
+
+void CommonUserTrackInfo::Print() const {
+
+}
+
+bool CommonUserTrackInfo::setIdxEdm4hep(int idxEdm4hep) {
+    m_idxEdm4hep = idxEdm4hep;
+}
+
+int CommonUserTrackInfo::idxEdm4hep() const {
+    return m_idxEdm4hep;
+}