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Your email address will not be published.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

  • March 20, 2025

    Inventory System 2 Alpha 4 available

    This release finally uses Godot Engine 4.4. It adds the GGCraftingSystem singleton and updates the GGInteractable2DStrategyCrafting class to use it. The crafting editor nodes now have prefixes, which makes it much easier to search for specific recipe or item nodes in larger crafting libraries. Some syntactic sugar was added as well. You can now easily …

  • December 22, 2022

    A GDScript refactoring exercise

    Arguably, more fun than writing code is removing code. I was assembling a split-screen multiplayer UI. The goal behavior is to show/hide the appropriate displays for the players, depending on how many players there are. Initially, the code to update the UI was very simple, because I started with two players. In that case, you …

  • October 9, 2023

    The Godot Jungle Demo

    It’s not Far Cry, nor Crysis, but it could be. The Realistic Jungle Demo demonstrates that Godot is capable of impressive visuals. If you want to run it yourself, download it from https://wrobot.itch.io/jungledemo. It was announced in this Reddit post. Update: The source code was released (with the commercial assets removed).

  • 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 …

    © 2025 GoGoGodot.io. All rights reserved.