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 …
Godot Engine 4 has a bug (#50824) that causes particle jitter when the game is paused. It does look quite distracting. The Bug in Action This is a proof-of-concept wave shooter running in Godot Engine 4.0.2. Pausing the game was initially just a simple process_mode toggle. But as shown in the video clip above, there …
The latest inventory system is now available and it focuses on multiplayer permissions. The new Access Manager component validates client requests to ensure players can’t cheat and interact with inventories they’re not supposed to be able to have access to. New features: Bug fixes:
Need optimized export templates with PCK encryption support but don’t want to have to set up a build pipeline or download the entire compilation toolchain on your computer? Well, now it is. Fill out the form, checkout, and we’ll email you the download link after the compilation completes. Compilation may take 30 minutes to 3 …
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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