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.
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 …
A new version of the Inventory System is available. This release includes various refinements to existing systems to flesh out more combat-related functionality. Inventory Ammo Provider The GGAmmoProvider component is responsible for providing ammunition to equipped weapons. Previously, it only had a “simple” strategy: Creating ammunition out of thin air. The new GGAmmoProviderInventoryStrategy pulls ammunition …
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 …
Here’s a collection of tutorials that are helpful if you’re new to using Control and Container nodes to create UIs in Godot 4. The Game Dev Artisan video covers creating a simple UI with a reload indicator for a simple 2D tank game: Clear Code’s 11+ hour Ultimate Introduction to Godot 4 has a chapter …
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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