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.
Godot Engine 4 has a bug (#50824) that causes particle jitter when the game is paused. It does look quite distracting. The Bug in Action This is a proof-of-concept wave shooter running in Godot Engine 4.0.2. Pausing the game was initially just a simple process_mode toggle. But as shown in the video clip above, there …
One of the benefits of working with Godot Engine is that GDScript allows one to operate high level. GDScript is dynamically typed, so not even variable types have to be specified, but I would strongly recommend using static typing wherever possible. It can help with performance but primarily adds clarity when trying to follow the …
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 …
In this 2018 GDC session, Spry Fox‘s Daniel Cook explains how to keep human beings from being treated as interchangeable, disposable, or abusable when designing multiplayer games. If you’re developing, or thinking about developing a multiplayer game, this is a great talk to better understand the challenges of designing multiplayer interactions that result in more …
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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Godot Engine 4 has a bug (#50824) that causes particle jitter when the game is paused. It does look quite distracting. The Bug in Action This is a proof-of-concept wave shooter running in Godot Engine 4.0.2. Pausing the game was initially just a simple process_mode toggle. But as shown in the video clip above, there …
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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 …
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