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.
When I think of video games, I generally still think of an application that is downloaded and runs on the client. Technically, that’s still the case with web-based exports from Godot Engine, since the web browser has to download the files before being able to run them. I thought maybe I could just run the …
In this 2018 GDC session, Spry Fox‘s Daniel Cook explains how to keep human beings from being treated as interchangeable, disposable, or abusable when designing multiplayer games. If you’re developing, or thinking about developing a multiplayer game, this is a great talk to better understand the challenges of designing multiplayer interactions that result in more …
I use an app called barrier. It allows you to share your mouse and keyboard with multiple devices. I use it, because I tend to have my laptop and Macbook sitting next to my PC, and it makes working across all devices very convenient. It’s a mix of a multi-monitor and multi-computer setup. Concept Your …
This release contains the new Godot editor integrations. It offers an Item Library bottom panel that makes it easier to manage your inventory item types, and an inspector plugin that lets you edit items in a GGItemCollection. This also reduces the need for manually creating GGItemData resources, which simplifies item management at design time significantly. …
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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