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.
Creating network connections with Godot is simple — as long as you have the other party’s IP address, and there’s no NAT gateway involved. Unfortunately, that’s exactly the problem in most cases. You don’t know the other party’s IP, and these days, just about everyone is behind a combination wifi router/gateway/firewall with NAT. Conceptually, NAT …
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:
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:
Here’s a collection of tutorials that are helpful if you’re new to using Control and Container nodes to create UIs in Godot 4. The Game Dev Artisan video covers creating a simple UI with a reload indicator for a simple 2D tank game: Clear Code’s 11+ hour Ultimate Introduction to Godot 4 has a chapter …
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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Creating network connections with Godot is simple — as long as you have the other party’s IP address, and there’s no NAT gateway involved. Unfortunately, that’s exactly the problem in most cases. You don’t know the other party’s IP, and these days, just about everyone is behind a combination wifi router/gateway/firewall with NAT. Conceptually, NAT …
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Here’s a collection of tutorials that are helpful if you’re new to using Control and Container nodes to create UIs in Godot 4. The Game Dev Artisan video covers creating a simple UI with a reload indicator for a simple 2D tank game: Clear Code’s 11+ hour Ultimate Introduction to Godot 4 has a chapter …