GeyserMC
The Player Locator Bar seems to be slightly messed up.
Describe the bug
When a bedrock player joins a server if a player is outside that players render distance the bedrock locator bar will display an invalid location.
To Reproduce
Join a server with a bedrock and java account and compare the two locator bars.
Expected behaviour
The bedrock locator bar should show the same positions as its java counterpart. (Which are correct)
Screenshots / Videos
https://youtu.be/v2YF8dlZD4E
Server Version and Plugins
Proxy:
Velocity 3.4.0-SNAPSHOT (git-81deb1ff-b521)
Server 1:
This server is running Paper version 1.21.1-133-ver/1.21.1@3cb8529 (2025-03-28T16:14:36Z) (Implementing API version 1.21.1-R0.1-SNAPSHOT)
You are running the latest version
Previous version: 1.20.6-151-a4f0f5c (MC: 1.20.6)
Server 2: (the one with the locator bar issue) This server is running Purpur version 1.21.7-2470-HEAD@8734844 (2025-07-05T02:53:44Z) (Implementing API version 1.21.7-R0.1-SNAPSHOT)
- You are 2 version(s) behind
Download the new version at: https://purpurmc.org/downloads
Previous: 1.21.7-2468-2d8cdd1 (MC: 1.21.7)
Geyser Dump
https://dump.geysermc.org/gHBSCw2Ao22EIrTZEOhDKQBtuNskR38t
Geyser Version
2.8.2-b874 (git-master-57f0489)
Minecraft: Bedrock Edition Device/Version
Confirmed on Minecraft for Windows, Suspected on Minecraft for PS5 but waiting for confirmation.
Additional Context
The example video I linked was a rather poor demonstration as only one of the icons was messed up. Usually it is most if not all, with the exception of those within the render distance of the bedrock user.
Unfortunately, it appears that this is hardcoded Bedrock client behavior - it chooses to display closeby players automatically, regardless if they're sent by the server.
Yea but the close players weren't the problem, it was only the people further away that would have the wrong location displayed. When the player with the broken locator got close to any of the incorrectly displayed players the bar would fix itself and as far as I could tell, stay that way.
Similar issue on my SMP. Bedrock locator bar is off by exactly 180 degrees when the other player is outside of render distance. When the other player comes within render distance the correct direction is shown on the bedrock player's locator bar. This suggests to me that perhaps when the other player is outside of render distance the locator bar is calculated server-side and the result would be sent to the bedrock client via a packet, and when the other player is within render distance the bedrock client does the logic for it client-side.
If this theory is true, this could possibly be fixed within Geyser, correct?
When a given player is a far distance away from the geyser player, the packet sent to the geyser player simulates the other player at 1000 blocks away from the geyser player. It does this using an angle given by the packet.
However, this angle seems to be used incorrectly to estimate the other player's location, using the equation:
dx = cos(angle) * 1000 dz = -sin(angle) * 1000
Through testing, I placed the geyser player at 0,0 and the other player at various locations and recorded the reported angle. Below are my findings, in the format of (otherPlayerX, otherPlayerZ) => angle => (computed dx, computed dz):
(0, 1000) => 0 => (1000, 0) (0, -1000) => pi => (-1000, 0) (1000, 0) => pi/2 => (0, -1000) (-1000, 0) => -pi/2 => (0, 1000)
It seems that the correct equation for computing dx, dz should be: dx = sin(angle) * 1000 dz = cos(angle) * 1000
I will implement this locally and test this out further.
Doing slightly more testing,
dx = -sin(angle) * 1000 dz = cos(angle) * 1000
Seems to be correct (note the negation of sin)