A minimal example of a VAE for Mario

This folder contains three scripts: vae.py implements a categorical VAE with MLP encoders and decoders, train.py trains it, and visualize.py shows a snapshot of the latent space.

Installing requirements

Create an environment using the tool of your choice. Python version >=3.9. Then do

pip install -r requirements.txt

Visualizing a pretrained model

I added an already-trained model under models/example.pt. Run

python visualize.py

to get a look at this example's latent space.

Using the simulator

I recently added a simulator.jar that lets you run levels directly from latent space. To do so, you'll need a version of Java that is above 8 (we used OpenJDK 15.0.2). Running

python simulator.py

should let you play content directly from latent space. Take a look at the functions implemented therein and get creative! The simulator outputs a JSON with telemetrics from the simulation, and if you set human_player=False it uses Robin Baumgarten's A star agent.

Troubleshooting in remote servers/containers

If you are working on a remote server/dev container, you might face the following issue:

Exception in thread "main" java.awt.HeadlessException: 
No X11 DISPLAY variable was set,
but this program performed an operation which requires it.

This happens because the Java simulator is expecting a screen! A way to solve this is by installing a virtual frame buffer. In Ubuntu, this can be achieved with

# Install a virtual frame buffer
apt-get install xvfb

and then run

# Export a display enviroment variable
export DISPLAY=99

# Run the virtual frame buffer in the background.
Xvfb :99 -screen 0 1366x768x24 -ac +extension GLX +render -noreset &

Using the simulator with Docker

We provide a dockerfile with the lightweight requirements for running simulator.py. This docker image builds on the Ubuntu 20.04 base, adding Python 3.9, Java 17, and installing Xvfb to be able to run simulator.jar. This image is already on docker hub, so you can either

docker pull miguelgondu/mario
docker run miguelgondu/mario

or

docker build -t mario .
docker run mario

Running Bayesian Optimization in latent space

I also include an example of how to run Bayesian Optimization in the latent space of the VAE. In it, I try to maximize the number of jumps. It is built using gpytorch and botorch, and you can play around with your GP definition in simple_bayesian_optimization.py. To run it, just call

python simple_bayesian_optimization.py

Cite this repository!

If you find this code useful, feel free to cite it!

@software{Gonzalez-Duque:Minimal_VAEMario:2023,
author = {González-Duque, Miguel},
title = {{Minimal implementation of a Variational Autoencoder on Super Mario Bros}},
url = {https://github.com/miguelgondu/minimal_VAE_on_Mario},
version = {0.1},
date = {2023-04-29}
}