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 version requires Godot Engine 4.3 and includes many refinements. New Drag and Drop system The Drag-and-Drop component has received a major overhaul. The previous system was quite complex and the separation of the classes that implemented the click-and-drag and click-and-release approaches had so much overlap …
Here’s a tutorial on how to create breakable objects in Blender and Godot. It covers the steps needed to design and implement breakable objects, including scripting and using physics properties to make objects break apart into smaller pieces upon collision or other interactions.
Arguably, more fun than writing code is removing code. I was assembling a split-screen multiplayer UI. The goal behavior is to show/hide the appropriate displays for the players, depending on how many players there are. Initially, the code to update the UI was very simple, because I started with two players. In that case, you …
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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A new version of the Inventory System is available. This version requires Godot Engine 4.3 and includes many refinements. New Drag and Drop system The Drag-and-Drop component has received a major overhaul. The previous system was quite complex and the separation of the classes that implemented the click-and-drag and click-and-release approaches had so much overlap …
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Here’s a tutorial on how to create breakable objects in Blender and Godot. It covers the steps needed to design and implement breakable objects, including scripting and using physics properties to make objects break apart into smaller pieces upon collision or other interactions.
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The shader used in the tutorial: https://godotshaders.com/shader/2d-fog-overlay-2/
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