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A Python module implemented in Rust for serializing and deserializing RLBot's flatbuffers

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rlbot-flatbuffers-py

A Python module implemented in Rust for serializing and deserializing RLBot's flatbuffers

The goal of this project

To provide a fast, safe, and easy to use Python module for serializing and deserializing RLBot's flatbuffers.

A majority of the code is generated in the codegen/ upon first compile and thrown into src/python.

This includes the code generated by flatc (living in src/generated), the Python wrapper binds to the generated Rust code, and the Python type hints (rlbot_flatbuffers.pyi).

Dev setup

  • Ensure Python 3.11+ is installed
  • Create a virtual Python environment
    • python3 -m venv venv
  • Activate the virtual environment
    • Windows: venv\Scripts\activate.bat
    • Linux: source venv/bin/activate
  • Install maturin
    • pip install maturin
  • Build & install for testing
    • maturin develop --release

To use in another Python environment, like if testing python-interface, you can build the wheel:

  • maturin build --release
  • (In another environment) pip install path/to/file.whl

The exact path of the wheel will be printed by maturin, just copy+paste it.

Basic usage

All classes and methods should have types hints readable by your IDE, removing the guesswork of common operations.

Creating

import rlbot_flatbuffers as flat

desired_ball = flat.DesiredBallState(
    physics=flat.Physics(
        location=flat.Vector3Partial(z=200),
        velocity=flat.Vector3Partial(x=1500, y=1500),
        angular_velocity=flat.Vector3Partial(),
    ),
)

desired_game_info = flat.DesiredGameInfoState(
    world_gravity_z=-100,
    game_speed=2,
)

desired_game_state = flat.DesiredGameState(
    ball_state=desired_ball,
    game_info_state=desired_game_info,
)

In the above code, we:

  • Set the ball to:
    • Location (0, 0, 200)
    • Velocity (1500, 1500, 0)
    • Angular velocity of (0, 0, 0)
  • Don't set the car states
  • Set the game info state:
    • World gravity to -100
    • Game speed to 2x default
    • Don't set end match or paused
  • Don't set any console commands

All values are optional when creating a class and have the proper defaults.

Reading values

import rlbot_flatbuffers as flat

def handle_packet(packet: flat.GamePacket):
    if packet.game_info.game_status not in {
        flat.GameStatus.Active,
        flat.GameStatus.Kickoff,
    }:
        # Return early if the game isn't active
        return

    # Print the ball's location
    print(packet.ball.physics.location)

    for car in packet.players:
        # Print the every car's location
        print(car.physics.location)

The goal of the above was to feel familiar to RLBot v4 while providing a more Pythonic interface.

  • All classes (not enums and unions) implement __match_args__ for easy destructuring via the match/case pattern.
    • Enums and unions and can still be used to match against the type, they just can't be destructured.
  • Every class implements __str__, __repr__, and __hash__ methods.
    • All enums also implement __int__ and __eq__.
  • Lists no longer have num_x fields accompanying them, they are just Python lists of the appropriate length.