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.
Development snapshot #4 of Godot Engine 4.1 is here. Among many other changes, it fixes a lighting issue related to using Light-only mode in CanvasItemMaterial (#44559). Unfortunately, it also introduced a UX issue with gradient color pickers (#77745), which makes it quite difficult to work with gradients at all. If you use gradients, I recommend …
A little while ago, I created a type of AudioManager to make it easier to work with sound files in bulk: Rather than assigning audio streams by hand, I was doing it programmatically; reading the contents of a directory and using load() to get the resources. It worked great and saved a lot of time …
The Terrain3D addon for Godot lets you create and manage 3D terrains within Godot. It looks quite promising for making landscapes, hills, valleys, and other natural environments. The addon provides tools for sculpting the terrain, and you can paint different textures like grass, dirt, or rock, and blend them smoothly. It also supports features like …
Godot-matcha is an addon that lets you use WebRTC for multiplayer games by handling matchmaking using WebTorrent trackers. Conceptually it’s quite an interesting, novel approach. WebTorrent uses a modified BitTorrent protocol that allows it to work with WebSockets. A WebTorrent tracker is essentially a directory service that keeps track of torrents offered by users. A …
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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Development snapshot #4 of Godot Engine 4.1 is here. Among many other changes, it fixes a lighting issue related to using Light-only mode in CanvasItemMaterial (#44559). Unfortunately, it also introduced a UX issue with gradient color pickers (#77745), which makes it quite difficult to work with gradients at all. If you use gradients, I recommend …
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The Terrain3D addon for Godot lets you create and manage 3D terrains within Godot. It looks quite promising for making landscapes, hills, valleys, and other natural environments. The addon provides tools for sculpting the terrain, and you can paint different textures like grass, dirt, or rock, and blend them smoothly. It also supports features like …
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