Bringing Pygame to the Browser with Pygbag

Ever wanted to create a browser-based video game or utility but didn't want to learn a whole lot of new 'stuff'?

This is the situation I was in recently. I had picked up some of my old computer magazines, and a maze-generation algorithm caught my eye. I thought I could share it here, but I didn't really want to have my desire for a playable demo dictate which language to use.

Enter Pygbag!

Pygbag makes it possible to run Pygame-based Python apps directly in a web browser using WebAssembly (wasm).

This means you can share your games and applications online without requiring users to install Python. It works on desktop and mobile browsers, making it a great option for bringing Python projects to the web.

WebAssembly is a portable binary-code format that runs almost as fast as native code. With Pygbag, your Pygame project gets converted into a format browsers can understand, allowing it to run smoothly online.

Setting Up Your Game for Pygbag

For Pygbag to work, your game needs to be structured properly. The key requirement is that your project folder, for example mazegen, must contain a main.py file. Inside this file, the game loop must be asynchronous using Python’s asyncio library.

Instead of running continuously, the event loop in a Pygbag game syncs with the display refresh rate, usually 60 times per second on desktops and sometimes lower on mobile. This helps keep performance smooth. To avoid lag or loading issues, it is best to preload any assets at the start of the game.

Installing Pygbag

To get started, install Pygbag along with Pygame if you have not already:

pip install pygame pygbag

Running mazegen in the Browser

Once your game is ready, running it in a browser is simple. Make sure your main script is called main.py, then open a terminal, navigate to the project folder, and run: