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.
Right after I got my Steam Deck, I wanted to know how hard it is to get a Godot game running on it. What’s the developer experience for someone who’s stepping through this for the first time? It was really easy to do, so I’m sharing this here, whether you’re following along or like to …
A new version of the Inventory System is available. This release includes a new structure placement feature and improves crafting. Structure Placement Players can now place structures from their inventory. When using an inventory item representing a structure, the player is prompted to select where to place it. The included demo lets players place an …
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 …
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 …
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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