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 …
This release improves weight management. Inventories can now configure an option weight limit, and item stacking and item transfer strategies are weight-aware. The crafting demo and crafting mechanic in the inventory tour have been improved. Auto-crafting is limited to the crafting slide, so that items don’t automatically and unexpectedly get crafted while stepping through the …
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 …
This release finally uses Godot Engine 4.4. It adds the GGCraftingSystem singleton and updates the GGInteractable2DStrategyCrafting class to use it. The crafting editor nodes now have prefixes, which makes it much easier to search for specific recipe or item nodes in larger crafting libraries. Some syntactic sugar was added as well. You can now easily …
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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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 …
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This release finally uses Godot Engine 4.4. It adds the GGCraftingSystem singleton and updates the GGInteractable2DStrategyCrafting class to use it. The crafting editor nodes now have prefixes, which makes it much easier to search for specific recipe or item nodes in larger crafting libraries. Some syntactic sugar was added as well. You can now easily …