ROS2 client receive from co-simulator

[mantkiew]

The ROS client now listens to /gs/tick_from_client topic and writes that to the client shared memory.
Implemented a simple mock_co_simulator.py that simply reposts information from /gs/tick (aka "tick from server") to /gs/tick_from_client.

It turns out that the shared memory for client layout is different than that of the server:
Client shared memory:

tick_count delta_time n_vehicles n_pedestrians
vid x y z vx vy active
pid x y z vx vy active

Server shared memory:

tick_count simulation_time delta_time n_vehicles n_pedestrians
origin_lat origin_lon origin_alt
vid v_type x y z vx vy yaw steering_angle
pid p_type x y z vx vy yaw

In particular, the field active is not available in the messages Vehicle and Pedestrian. It might have to be added.

Testing (the exact order does not matter):
0. install ROS2 and build the client

$ bash scripts/setup-conda-forge-env.bash --ros2

2. start a scenario

$ micromamba -n gss run python3 GSServer.py -s scenarios/coretest_scenarios/straightdrive.gs.osm --no-dash -wi

3. start the mock co-simulator

$ micromamba -n gss run bash -c 'source /home/ma/geoscenarioserver/colcon_ws/install/setup.bash && ros2 run geoscenario_client mock_co_simulator'

4. start the ROS2 client

$ micromamba -n gss run bash -c 'source /home/ma/geoscenarioserver/colcon_ws/install/setup.bash && ros2 run geoscenario_client geoscenario_client'

Observe rqt topics.

Additional changes:

• clean shutdown to handle SIGINT and SIGTERM

[mantkiew]

@rodrigoqueiroz @icolwell-as should we unify the shared memory layout for the client and the server?

Why the active bit is only coming from the client? Should this be added to Vehicle and Pedestrian?

[icolwell-as]

Nice!

[icolwell-as]

@rodrigoqueiroz @icolwell-as should we unify the shared memory layout for the client and the server?

Why the active bit is only coming from the client? Should this be added to Vehicle and Pedestrian?

We don't use the client shared memory, we only read from the server. But I think the two shared memory spaces serve slightly different purposes. The server memory shares the state of everything simulated by the GSS, whereas the client memory is only for reporting back the state of any ego or co-simulated vehicles right?
If that is true, I think it's totally fine to keep them different, since they have different purposes.