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.
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:
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 …
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 …
When I think of video games, I generally still think of an application that is downloaded and runs on the client. Technically, that’s still the case with web-based exports from Godot Engine, since the web browser has to download the files before being able to run them. I thought maybe I could just run the …
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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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 …
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