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Your email address will not be published.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 27, 2022

    Projectiles going through collision objects

    Ever had the problem where you’re firing a bullet or some kind of projectile at high speeds, and it just goes right through the collision object, instead of hitting it? Here’s a weapon that fires a bullet at random velocities, to demonstrate the issue: The bullets impact the character in various places, rather than at …

  • August 1, 2022

    Running Godot Games on Steam Deck

    Right after I got my Steam Deck, I wanted to know how hard it is to get a Godot game running on it. What’s the developer experience for someone who’s stepping through this for the first time? It was really easy to do, so I’m sharing this here, whether you’re following along or like to …

  • February 17, 2025

    Inventory System 2 Alpha 2 available

    This release contains the new Godot editor integrations. It offers an Item Library bottom panel that makes it easier to manage your inventory item types, and an inspector plugin that lets you edit items in a GGItemCollection. This also reduces the need for manually creating GGItemData resources, which simplifies item management at design time significantly. …

  • April 21, 2024

    Inventory System v1.13 available

    It’s been a while, but it was worth the wait. The latest version of the Inventory System is now available, with a long list of features, improvements, fixes, and documentation. This time the focus is on multiplayer. Let’s cover the features first: Bug fixes:

    © 2026 GoGoGodot.io. All rights reserved.