How to instantiate it

Instantiating the SGG

    # setup the CARLA client
    client = carla.Client('localhost', 2000)
    # This is longer than typical - the client timeout must wait for the SGG indexing to complete
    client.set_timeout(120.0)

    # load the environment
    world = client.load_world('Town10_Opt')  # set town string to load a different map

    # it is recommended to run the simulation in synchronous mode when generating scene graphs
    # to ensure alignment between the scene graph and other sensor data
    settings = world.get_settings()
    settings.synchronous_mode = True
    settings.fixed_delta_seconds = 0.05
    world.apply_settings(settings)
    world = client.reload_world(False)

    # create the ego vehicle
    blueprint_library = world.get_blueprint_library()
    ego_bp = blueprint_library.find('vehicle.tesla.model3')  # change the blueprint id for a different vehicle type
    spawn_points = world.get_map().get_spawn_points()
    ego = world.spawn_actor(ego_bp, spawn_points[0])

    # Setup the SGG - this call will take several seconds while the SGG indexes the world and performs initial bookkeeping
    sgg = SGG(client, ego.id)

Generating the Scene Graph

This method takes in two parameters: the world snapshot and the ego vehicle control commands. The control commands can either be a dictionary as shown below, or an instance of carla.VehicleControl.

        for frame_number in range(100):
            # get the simulation state world snapshot
            frame = world.tick()
            # can either be a dictionary as below, or carla.VehicleControl
            ego_control = {
                'throttle': 5.0,
                'steer': -1.0
            }
            sg = sgg.generate_graph_for_frame(frame, ego_control)

Full Example

See mwe.py for a full minimal working example.