The Client connects CARLA to the server which runs the simulation. Both server and client contain a CARLA library (libcarla) with some differences that allow communication between them. Many clients can be created and each of these will connect to the RPC server inside the simulation to send commands. The simulation runs server-side. Once the connection is established, the client will only receive data retrieved from the simulation. Walkers are the exception. The client is in charge of managing pedestrians so, if you are running a simulation with multiple clients, some issues may arise. For example, if you spawn walkers through different clients, collisions may happen, as each client is only aware of the ones it is in charge of.
The client also has a recording feature that saves all the information of a simulation while running it. This allows the server to replay it at will to obtain information and experiment with it. [Here](recorder_and_playback.md) is some information about how to use this recorder.
Executes a list of commands on a single simulation step and retrieves no information. If you need information about the response of each command, use the **<font color="#7fb800">apply_batch_sync()</font>** function right below this one.
[Here](https://github.com/carla-simulator/carla/blob/10c5f6a482a21abfd00220c68c7f12b4110b7f63/PythonAPI/examples/spawn_npc.py#L126) is an example on how to delete the actors that appear in carla.ActorList all at once.
Executes a list of commands on a single simulation step, blocks until the commands are linked, and returns a list of <b>command.Response</b> that can be used to determine whether a single command succeeded or not. [Here](https://github.com/carla-simulator/carla/blob/10c5f6a482a21abfd00220c68c7f12b4110b7f63/PythonAPI/examples/spawn_npc.py#L112-L116) is an example of it being used to spawn actors.
Returns a list of strings containing the paths of the maps available on server. These paths are dynamic, they will be created during the simulation and so you will not find them when looking up in your files. One of the possible returns for this method would be:
Returns the client libcarla version by consulting it in the "Version.h" file. Both client and server can use different libcarla versions but some issues may arise regarding unexpected incompatibilities.
Time in seconds where to start playing the simulation. Negative is read as beginning from the end, being -10 just 10 seconds before the recording finished.
The server will start running the simulation `name` previously recorded. The time to start and stop can be stated and if the recreation finishes, the vehicles will continue their behaviour as usual, managed by the server. During the simulation we can follow a specific actor using its ID.
# --------------------------------------
- def_name:generate_opendrive_world
params:
- param_name:opendrive
type:str
doc:>
OpenDRIVE data as `string`.
doc:>
Loads a new world with a basic physical topology generated from an OpenDRIVE file passed as `string`.
It is similar to `client.load_world(map_name)` but allows for custom OpenDRIVE maps in server side.
Cars can drive around the map, but there are no graphics besides the road and sidewalks.
The terminal will show the information registered for actors considered blocked. An actor is considered blocked when it does not move a minimum distance in a period of time, being these `min_distance` and `min_time`.
When true, will show all the details per frame (traffic light states, positions of all actors, orientation and animation data...), but by default it will only show a summary.
The information saved by the recorder will be parsed and shown in your terminal as text (frames, times, events, state, positions...). The information shown can be specified by using the `show_all` parameter. [Here](recorder_binary_file_format.md) is some more information about how to read the recorder file.
Name of the file to write the recorded data. A simple name will save the recording in 'CarlaUE4/Saved/recording.log'. Otherwise, if some folder appears in the name, it will be considered an absolute path.
