How to build with LibCarla and UE4 content with ROS2

[pravinkmr26]

Hi team, I see WITH_ROS2 c++ macro is used in many places, especially the sensor outputs. when I tried enabling the ros2 flag in linux make file I get a bunch of compiler errors, llike fastdds headers are missing, etc. while I can solve them manually, I want to understand, is there any script or specific steps that I need to follow to enable ROS2?

[xavisolesoft]

You just need to build and launch CARLA with the next command:

make launch ARGS="--ros2"

Note that this will enable the macro WITH_ROS2, so you do not need to enable it by hand.

[pravinkmr26]

Yes, thanks. I figured it out. but when I was looking at the code I see the Ros publishers use dds types instead of ROS types. I would like to understand how the subscriber would use this data. I was hoping that the data would be published to ROS types (say sensor_msgs::PointCloud2 for ex). can you direct me to some design docs so that I can understand how publishing over ROS would work from a high level. (publisher&subscriber flow)

[pravinkmr26]

or do you think this is a different discussion?

[xavisolesoft]

I think is a good idea to open a new discussion for this new topic.
This will help other people to find the discussion.

[uff1199]

For others: In CARLA 0.9.16 ros2 middleware is supported. During sensor spawning via the python API only enable_for_ros() needs to be called for each actor. The topics can be then subscribed as ROS2 topics, which I tested with ROS2 Humble.