GymGodot

Godot Engine as an OpenAI Gym environment for Reinforcement Learning.

Overview

gym-godot : Godot Side (client)

• The 'Environment node', created by the user, implements the required methods (execute_action(), get_observation(), get_reward(), reset() and is_done()).
• The GymGodot node (GymGodot.tscn) bridges the 'Environment node' node and the Python side server.

gym-server : Python Side (server)

• gym-server communicates with its Godot client and exposes it as a Gym environment.

Communications between the server and client are done with WebSocket JSON messages (protocol.md)

Installation & Usage

• Download or clone this repo.
• Add GymGodot.tscn, GymGodot.gd and WebSocketClient.gd from /gym-godot to your Godot project folder. Then add the GymGodot.tscn node into your scene.
• Create a node (the 'Environment node') that implements the required functions.
• In the inspector, set GymGodot Node's 'Environment Node' property to your 'Environment node'.
• On the python side, install gym-server with : pip install -e gym-server. Use it in your training script like a regular Gym environment.

A step-by-step tutorial is available in the tutorial.ipynb notebook.

Example environments

Cartpole

gym-godot/examples/cartpole/

Description : cartpole.md

Pendulum

gym-godot/examples/pendulum/

Description : pendulum.md

Mars Lander

gym-godot/examples/mars_lander/

Description : mars_lander.md

Notes

• Make sure to open the project (gym-godot/project.godot) in the Godot Editor at least once before using the example environments (so that the resources are imported).

• Only tested on Linux & Godot 3.3.

• The code follows the Gym API so it might work with other Gym-compatible frameworks but has only been tested with Stable-Baselines 3.

• No current plan for further improvements, maintenance or support.