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’s resources are quite powerful. However, modifying a resource class doesn’t automatically update any corresponding .tres files, unless you happen to edit a scene that uses that resource in some way. This doesn’t impact runtime behavior — the game still runs as expected. But it can impact version control and result in a messier diff …
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:
Hugo-Dz created Super Godot Galaxy: https://github.com/Hugo-Dz/super-godot-galaxy, which he announced in this Reddit post. It uses the 3D Starter Kit from Kenney and shows how to achieve the effect of applying gravity toward the center of a small spherical planet.
This release addresses an issue that arose due to Godot 4.4 changes in how JSON is deserialized. Relevant Godot issues: #103374 and #61464. Makes sense why it was changed, but it might impact anyone unaware who’s consuming a JSON-based API, and wondering why responses may not be as expected. In addition, this release now includes character damage and …
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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Update all resources after modifying a resource class
Godot’s resources are quite powerful. However, modifying a resource class doesn’t automatically update any corresponding .tres files, unless you happen to edit a scene that uses that resource in some way. This doesn’t impact runtime behavior — the game still runs as expected. But it can impact version control and result in a messier diff …
Inventory System v1.4 available
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:
Super Godot Galaxy Concept
Hugo-Dz created Super Godot Galaxy: https://github.com/Hugo-Dz/super-godot-galaxy, which he announced in this Reddit post. It uses the 3D Starter Kit from Kenney and shows how to achieve the effect of applying gravity toward the center of a small spherical planet.
Inventory System 2 Alpha 5 available
This release addresses an issue that arose due to Godot 4.4 changes in how JSON is deserialized. Relevant Godot issues: #103374 and #61464. Makes sense why it was changed, but it might impact anyone unaware who’s consuming a JSON-based API, and wondering why responses may not be as expected. In addition, this release now includes character damage and …