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.
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 …
Are you using @onready to reference nodes? There’s a better way! Here’s a simple example of how many tutorials use @onready to reference nodes: That script is attached to a CanvasLayer node with a ProgressBar called HealthBar. And yet, when running the scene, it will throw an error: This is because there’s actually a spelling …
Godot’s resources are quite powerful. However, modifying a resource class doesn’t automatically update any corresponding .tres files, unless you happen to edit a scene that uses that resource in some way. This doesn’t impact runtime behavior — the game still runs as expected. But it can impact version control and result in a messier diff …
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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Inventory System v1.18 available
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 …
Inventory System v1.8.1 available
A quick update to yesterday’s release with a few fixes:
Ditch @onready, use @export instead
Are you using @onready to reference nodes? There’s a better way! Here’s a simple example of how many tutorials use @onready to reference nodes: That script is attached to a CanvasLayer node with a ProgressBar called HealthBar. And yet, when running the scene, it will throw an error: This is because there’s actually a spelling …
Update all resources after modifying a resource class
Godot’s resources are quite powerful. However, modifying a resource class doesn’t automatically update any corresponding .tres files, unless you happen to edit a scene that uses that resource in some way. This doesn’t impact runtime behavior — the game still runs as expected. But it can impact version control and result in a messier diff …