Managing actors info (signals and traffic lights)


I’m both working on creating new Carla maps and parsing its information.

My objetive is to parse some info from the map for using it to control an autonomous vehicle. Specificly I want to parse the info from signals like stops or traffic lights.

I see that these ones are defined as “carla actors” so I could use the “world.get_actors()” to get a list with all of them. (Any other suggestions about how to do it are appreciated)

Thats working on Carla maps like Town04 but, but It isn’t in new maps created with VectorZero (RoadRunner).

On the other hand, I see that there is no info about any “stop signal” in the xodr file of Town04 (that does have “stop signals” actors), but there is info about the stop signal in the xodr file when I create a new simple map on VectorZero(RoadRunner) with a road and stop signal.

So te question is, where and how are these actors(signals) defined? Which are the options for the “wildcard_pattern” that match the type_id of the actors and where are defined?

Thank you for your time.

Hi, @Adidi!

Let me give you a brief overview:

  • carla.Landmark: These instances represent all the signals that are described in the OpenDRIVE file of the map. They are not actors though, as they are not present in the simulation.
  • carla.TrafficSign and carla.TrafficLight: These are actors. The simulator automatically creates them when starting the simulation, using the information in the OpenDRIVE files. That means that traffic lights, stop and yields exist as both, actors and landmarks.

This was implemented during the transition to 0.9.8~0.9.9. The CARLA maps were created before that. In previous CARLA maps, there are no signals in the .xodr file. As the landmarks were not implemented, the developers placed them manually, and only exist as actors. That may be the reason for the discrepancies between your RoadRunner maps and the CARLA maps.

The blueprints for traffic light and traffic signs are not accessible from the Blueprint Library, as they are either carefully placed by developers (CARLA maps) or automatically generated by the simulator (new maps).

Now I have a better idea about it.
But, in order to that, Town10HD should have signals info into the xodr file (that is the OpenDrive file)? Because I still can not find any signals info into the xodr file.
Anyway I’m going to try the new landmarks commands so I’ve just installed the 0.9.9 version.
If you want Yak, we can keep talking in the Discord Carla channel
Thank you again

I am afraid that Town10HD still has no landmarks in the OpenDRIVE file, as development started before these were implemented.
And sure, you can find me in the Discord server, anything you need.

The same issue. I also found the landmarks can not be found with the API.
@Yak. Do you have any idea to generate it? or when the new version map can be released.
Thanks !