geant events for multiple scattering

src/HEP/Geant/Scene.cpp

@@ -54,10 +54,27 @@ private:
   class SceneImpl *m_Owner;
 };
 
+static void CheckGeant4Environment() {
+  static bool checked = false;
+  if (checked) return;
+  checked = true;
+  if (!std::getenv("G4ENSDFSTATEDATA")) {
+    std::cerr << "********************************************************" << std::endl;
+    std::cerr << " WARNING: Geant4 environment variables are not set!" << std::endl;
+    std::cerr << " Please activate the environment before running:" << std::endl;
+    std::cerr << "   micromamba activate mutom" << std::endl;
+    std::cerr << "********************************************************" << std::endl;
+  }
+}
+
 class SceneImpl {
 public:
   // constructor //
-  SceneImpl() : m_RunManager(G4RunManagerFactory::CreateRunManager()) {}
+  SceneImpl() : m_RunManager(G4RunManagerFactory::CreateRunManager(G4RunManagerType::Serial)),
+                m_Emitter(nullptr),
+                m_Output(nullptr) {
+    m_RunManager->SetUserInitialization(new PhysicsList);
+  }
 
   // destructor //
   ~SceneImpl() { 
@@ -68,8 +85,8 @@ public:
   void Initialize() {
     // Set mandatory initialization classes for Geant4
     m_RunManager->SetUserInitialization(new SceneDetectorConstruction(this));
-    m_RunManager->SetUserInitialization(new PhysicsList);
-    m_RunManager->SetUserInitialization(new ActionInitialization);
+    m_RunManager->SetUserInitialization(
+        new ActionInitialization(m_Emitter, m_Output));
 
     // Initialize Geant4
     m_RunManager->Initialize();
@@ -79,6 +96,8 @@ public:
   Vector<Solid *> m_Solids;
   Solid *m_World = nullptr;
   G4RunManager *m_RunManager;
+  EmitterPrimary *m_Emitter;
+  Vector<GeantEvent> *m_Output;
 };
 
 SceneDetectorConstruction::SceneDetectorConstruction(SceneImpl *owner) 
@@ -91,10 +110,10 @@ G4VPhysicalVolume *SceneDetectorConstruction::Construct() {
 
 
 
-
-
-
-Scene::Scene() : d(new SceneImpl()) {}
+Scene::Scene() {
+  CheckGeant4Environment();
+  d = new SceneImpl();
+}
 Scene::~Scene() { delete d; }
 
 void Scene::AddSolid(Solid *solid, Solid *parent) { 
@@ -143,9 +162,26 @@ void Scene::ConstructWorldBox(const ContainerBox *box, const char *material) {
   d->m_World->SetTransform(transform);
 }
 
+void Scene::SetEmitter(EmitterPrimary *emitter) {
+  d->m_Emitter = emitter;
+}
+
 void Scene::Initialize() {
   d->Initialize();
 }
 
+void Scene::RunSimulation(int nEvents, Vector<GeantEvent> &results) {
+  d->m_Output = &results;
+
+  // Re-initialize ActionInitialization with the output buffer
+  // (ActionInitialization was already set during Initialize, but we need
+  //  to ensure the output pointer is current)
+  d->m_RunManager->SetUserInitialization(
+      new ActionInitialization(d->m_Emitter, &results));
+
+  d->m_RunManager->BeamOn(nEvents);
+}
+
 } // namespace Geant
 } // namespace uLib
+