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.
The latest version includes a few new enhancements, and an experiment: The sequencer demo uses inventory instances to hold music notes, which can be played back. This was inspired by music trackers that were popular in the 90s, such as Scream Tracker and Impulse Tracker. The sequencer isn’t meant to be a production-ready digital audio …
A little while ago, I created a type of AudioManager to make it easier to work with sound files in bulk: Rather than assigning audio streams by hand, I was doing it programmatically; reading the contents of a directory and using load() to get the resources. It worked great and saved a lot of time …
Version 1.0 of the Inventory System is now available. It includes a few new additions since the closed beta: Lots of fixes found their way into this release as well:
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 …
godot-matcha: Free multiplayer without a server
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.
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The latest version includes a few new enhancements, and an experiment: The sequencer demo uses inventory instances to hold music notes, which can be played back. This was inspired by music trackers that were popular in the 90s, such as Scream Tracker and Impulse Tracker. The sequencer isn’t meant to be a production-ready digital audio …
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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 …