remove hits while passing neutral particle

Simulation/DetSimSD/src/GenericTrackerSensitiveDetector.cpp

@@ -23,10 +23,11 @@ void GenericTrackerSensitiveDetector::Initialize(G4HCofThisEvent* HCE){
 }
 
 G4bool GenericTrackerSensitiveDetector::ProcessHits(G4Step* step, G4TouchableHistory*){
-  
   G4TouchableHandle touchPost = step->GetPostStepPoint()->GetTouchableHandle(); 
   G4TouchableHandle touchPre  = step->GetPreStepPoint()->GetTouchableHandle(); 
   dd4hep::sim::Geant4StepHandler h(step);
+  if (fabs(h.trackDef()->GetPDGCharge()) < 0.01) return true;
+
   dd4hep::Position prePos    = h.prePos();
   dd4hep::Position postPos   = h.postPos();
   dd4hep::Position direction = postPos - prePos;

Simulation/DetSimSD/src/TrackerCombineSensitiveDetector.cpp

@@ -23,6 +23,8 @@ void TrackerCombineSensitiveDetector::Initialize(G4HCofThisEvent* HCE){
 
 G4bool TrackerCombineSensitiveDetector::ProcessHits(G4Step* step, G4TouchableHistory*){
   dd4hep::sim::Geant4StepHandler h(step);
+  if (fabs(h.trackDef()->GetPDGCharge()) < 0.01) return true;
+
   bool return_code = false;
   if ( userData.current == -1 ) userData.start(getCellID(step), step, h.pre);
   else if ( !userData.track || userData.current != h.track->GetTrackID() ) {