Go, Go, Godot!
  • 0

godot-matcha: Free multiplayer without a server

December 23, 2023

Godot-matcha is an addon that lets you use WebRTC for multiplayer games by handling matchmaking using WebTorrent trackers. Conceptually it’s quite an interesting, novel approach.

WebTorrent uses a modified BitTorrent protocol that allows it to work with WebSockets. A WebTorrent tracker is essentially a directory service that keeps track of torrents offered by users. A torrent is uniquely identified by its info_hash, so if you have the torrent information, you can look up who is offering a file for download.

Rather than tracking a specific torrent file, godot-matcha generates a random identifier, which it uses as a room (or lobby). If another player has the same identifier they exchange the WebRTC’s SDP details to establish a connection.

Connecting players this way is essentially free. This is a suitable approach for mobile games, for example, where you start a game, and share an identifier with someone else to join in. Mobile party games, for example, use such an approach: One player starts a game, and others join by using some random id such as “FJRLE”.

While godot-matcha is a great proof of concept, I’ve done some testing that showed that the various clients disagree on their unique IDs. This results in challenges when setting the multiplayer authority, a key part of making the high-level multiplayer abstraction work well. The reason for the mismatch is how godot-matcha creates offers, which sets a random id as peer ID before the peers are even connected.

In contrast, the godot-demo-projects repository has a webrtc_signaling demo, which uses the lobby/signaling server to tell the clients their ID, so that all clients (including the one acting as the server) add the same peer ID.

gdscriptnetworking
Posted in Godot.
Share
Previous2D Fog Effect Shader Tutorial
NextCreating a UDP peer-to-peer connection

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Related Posts

  • October 23, 2023

    Fire, Rain, and Black Hole particle effects

    This video is from December last year and uses Godot 4.0-beta7, but I thought it was interesting, because… particle effects!

  • August 3, 2022

    Share your Computer’s Mouse and Keyboard with your Steam Deck

    I use an app called barrier. It allows you to share your mouse and keyboard with multiple devices. I use it, because I tend to have my laptop and Macbook sitting next to my PC, and it makes working across all devices very convenient. It’s a mix of a multi-monitor and multi-computer setup. Concept Your …

  • January 15, 2025

    Inventory System 2 Alpha 1 available

    The first alpha of the inventory system v2 is now available. For v2, a lot of refactoring work has been done with a focus on improving the developer experience. As part of that, the naming convention of the addon classes was streamlined and is more consistent now. The GDScript documentation comments have been improved significantly …

  • February 5, 2024

    Inventory System v1.4 available

    A smaller update. The inventory components now have custom icons to make it easier to tell them apart. This release also includes additional bug fixes:

    © 2026 GoGoGodot.io. All rights reserved.