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.
Godot Engine 4.0 has been released per official announcement. With version 4.0, Godot has gone through “3+ years of breaking and rebuilding from the ground up, a complete core overhaul and a full engine rewrite, through 17 alphas, 17 betas and 6 release candidates“. The announcement post is credited to “2000+ Godot contributors.” It’s a …
I’m wrapping up development on version 1 of the Inventory System, which is currently at v1.18.1. All core functionality is in place, and it provides many quality-of-life features. The guide covers and walks through most of the code base, and the demo projects show off a lot of use cases. This first version has been …
For some reason, my Godot game would no longer launch on the Steam Deck. I could hear it running as if it were running in the background, but the screen kept showing the Steam Deck’s UI. Since it’s all Linux I figured it should be possible to just drop to the command line and launch …
A little while ago, I created a type of AudioManager to make it easier to work with sound files in bulk: Rather than assigning audio streams by hand, I was doing it programmatically; reading the contents of a directory and using load() to get the resources. It worked great and saved a lot of time …
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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