def Construct(self): # pylint: disable-msg=C0103
"""Construct nuSTORM from a GDML file"""
# Parse the GDML
self.world = self.gdml_parser.GetWorldVolume()
# Create sensitive detector
self.sensitive_detector = ScintSD()
# Get logical volume for X view, then attach SD
my_lv = G4.G4LogicalVolumeStore.GetInstance().GetVolumeID(1)
assert my_lv.GetName() == "ScintillatorBarX"
my_lv.SetSensitiveDetector(self.sensitive_detector)
# Get logical volume for Y view, then attach SD
my_lv = G4.G4LogicalVolumeStore.GetInstance().GetVolumeID(2)
assert my_lv.GetName() == "ScintillatorBarY"
my_lv.SetSensitiveDetector(self.sensitive_detector)
my_lv = G4.G4LogicalVolumeStore.GetInstance().GetVolumeID(0)
assert my_lv.GetName() == "SteelPlane"
# field
self.field_manager = G4.G4FieldManager()
self.my_field = MagneticField.WandsToroidField(self.field_polarity)
self.field_manager.SetDetectorField(self.my_field)
self.field_manager.CreateChordFinder(self.my_field)
my_lv.SetFieldManager(self.field_manager, False)
self.log.info("Materials:")
self.log.info(G4.G4Material.GetMaterialTable())
# Return pointer to world volume
return self.world
