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 hole-punching is pretty simple, and this video explains how it’s done with just netcat.
In a nutshell:
listen on a particular port (e.g. 50001)
nc -u -l 50001
echo ‘hello’ | nc -u ipaddr 50001
echo ‘hole punch’ | nc -u -p 50001 ipaddr 50002
third party exchanges ip addresses
Putting it all together, player A (hosting a game) would require the game to connect to the directory server.
The directory server would list the game as something a player can now connect to.
player B (client who wants to join) will tell the directory service that it wants to connect, and will send its info
The directory server forwards the information to player A (host), player A will then send a packet to player B, and respond to the directory server
The directory server will then tell player B to go ahead and connect to player A.
Player B should be able to punch through to player A
With Godot, the connections from client to host would use ENetMultiplayerPeer.create_client(), which can specify the local port.
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 …
A new version of the Inventory System is available with more multiplayer-related features. The Multiplayer Interaction Demo can now run in multiple modes, through two separate implementations of the Character scene: The simple character scene leverages the MultiplayerSynchronizer and can either let the client have authority and move the character, or have the client send …
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:
Any sufficiently large code base needs documentation. Documentation tends to come in all sorts of shapes and sizes. Among them are high-level architecture and design docs, class and method interface documentation, and inline comments to explain optimized or complex algorithms so the reader doesn’t have to parse the logic in their head (often, this is …
Creating a UDP peer-to-peer connection
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 hole-punching is pretty simple, and this video explains how it’s done with just netcat.
In a nutshell:
Putting it all together, player A (hosting a game) would require the game to connect to the directory server.
With Godot, the connections from client to host would use ENetMultiplayerPeer.create_client(), which can specify the local port.
Here’s an older example of a signaling server: https://github.com/Faless/gd-webrtc-signalling/tree/master
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