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.
Ever had the problem where you’re firing a bullet or some kind of projectile at high speeds, and it just goes right through the collision object, instead of hitting it? Here’s a weapon that fires a bullet at random velocities, to demonstrate the issue: The bullets impact the character in various places, rather than at …
Normally I use OBS for screen recording, but there are cases where it makes sense to use Godot’s built-in movie writer that was recently announced. For example, if you have a slow PC or really demanding game, OBS will skip frames. It makes sense since OBS is just recording what’s on the screen in real …
Here’s a collection of tutorials that are helpful if you’re new to using Control and Container nodes to create UIs in Godot 4. The Game Dev Artisan video covers creating a simple UI with a reload indicator for a simple 2D tank game: Clear Code’s 11+ hour Ultimate Introduction to Godot 4 has a chapter …
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 …
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
Related Posts
Projectiles going through collision objects
Ever had the problem where you’re firing a bullet or some kind of projectile at high speeds, and it just goes right through the collision object, instead of hitting it? Here’s a weapon that fires a bullet at random velocities, to demonstrate the issue: The bullets impact the character in various places, rather than at …
Making videos for the web with Godot 4’s Movie Writer
Normally I use OBS for screen recording, but there are cases where it makes sense to use Godot’s built-in movie writer that was recently announced. For example, if you have a slow PC or really demanding game, OBS will skip frames. It makes sense since OBS is just recording what’s on the screen in real …
Building UIs in Godot 4
Here’s a collection of tutorials that are helpful if you’re new to using Control and Container nodes to create UIs in Godot 4. The Game Dev Artisan video covers creating a simple UI with a reload indicator for a simple 2D tank game: Clear Code’s 11+ hour Ultimate Introduction to Godot 4 has a chapter …
Terrain3D for Godot has been released
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 …