Hide Coordinates

Server-side Fabric mod to prevent sending real coordinates to the client. Based on and partly copied from the Spigot version CoordinateOffset by Joshua Prince.
Credit also goes to Patbox for a small sample of code I used from Polymer!

Features

• Players' coordinates are offset so that the location they entered the current world (join, teleport, portal or respawn) is shown to them as 0, 0.
• Admins can use /coordoffset get to find their own offset.
• Admins can use /coordoffset set [pos] to change their own offset such that the specified pos is in the 0,0 chunk for them, or /coordoffset set none to disable the offset.
• Any worldborder wall is only sent to players who can see it. This is to prevent client-side mods from instantly figuring out the offset from world border center information.

Why?

The gamerule reducedDebugInfo hides coordinates from the debug screen, but this can be easily circumvented using a client-side mod. This mod hides the coordinates for real by offsetting all coordinates sent to the client.
A server that wants to actually enforce the gamerule reducedDebugInfo without an honour system will need a mod like this. This is my attempt at an implementation :)

Disclaimer

I'm a new modder. I needed this for a server I'm working on and made it as a learning opportunity. Therefore the mod doesn't have all the features, the code is quite messy, and there could be bugs or crashes. But I still figured it might be useful to some others. Feel free to use the code as you please, and improvement suggestions are welcome!
Known issues:

• The main feature missing here from CoordinateOffset are the vast configuration options. Offsets are always set so you spawn in chunk 0,0 and this resets on death and dimension change.
• Worldborder growing or shrinking looks really weird.
• It's possible that I missed some packets that need the offset, let me know!