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.
Hugo-Dz created Super Godot Galaxy: https://github.com/Hugo-Dz/super-godot-galaxy, which he announced in this Reddit post. It uses the 3D Starter Kit from Kenney and shows how to achieve the effect of applying gravity toward the center of a small spherical planet.
This release addresses an issue that arose due to Godot 4.4 changes in how JSON is deserialized. Relevant Godot issues: #103374 and #61464. Makes sense why it was changed, but it might impact anyone unaware who’s consuming a JSON-based API, and wondering why responses may not be as expected. In addition, this release now includes character damage and …
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 …
We’re excited about this release, which includes a range of quality-of-life additions and refinements. Drag-and-drop support has been improved with a second strategy: Click-and-release: Simply clicking (and releasing) an item will pick it up. This leverages Godot’s force-drag functionality and approximates the drag-and-drop behavior that games like Valheim and Palworld use in their inventory items. …
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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Hugo-Dz created Super Godot Galaxy: https://github.com/Hugo-Dz/super-godot-galaxy, which he announced in this Reddit post. It uses the 3D Starter Kit from Kenney and shows how to achieve the effect of applying gravity toward the center of a small spherical planet.
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This release addresses an issue that arose due to Godot 4.4 changes in how JSON is deserialized. Relevant Godot issues: #103374 and #61464. Makes sense why it was changed, but it might impact anyone unaware who’s consuming a JSON-based API, and wondering why responses may not be as expected. In addition, this release now includes character damage and …
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