Some sort of player desync when teleporting?

[vgskye]

(originally ChloeTax/hexxytest3#148)

Describe the bug
When teleporting far, sometimes your movement gets all Weird(see below)

To Reproduce
Steps to reproduce the behavior:

1. Teleport to a faraway location, preferably near another player for testing
2. See that:

• To the other player, you aren't shown as moving
• Server-side velocity changes using mods do not work

(this is weirdly unreliable to reproduce! only some setups trigger it and only sometimes)

Expected behavior
Nothing of note regarding server-side velocity changes happen and you are seen as moving to the other player.

Screenshots

Runtime info (please complete the following information):

• OS: Linux amd64
• Minecraft version: 1.20.1
• Mod version: 0.2.0+beta.7.102
• Mod branch: (fill this if you are not using the default ver branches)

Crash reports / logs
This generates no log messages and isn't a crash, so irrelevant

Other mods
This was tested on a modpack(packwiz repo linked above), exact isolation.... would be good but I'm a bit tired rn so I'll do that later(apparently doesn't happen with Just VMP though)

Checklist

• I am using the official version of the mod.
• I tried the latest development version but the issue persists.
• I searched for similar open issues and could not find an existing bug report on this.

Additional context
Seems to be particularly visible when teleporting multiple times in a single tick to another player. Disabling the use_optimized_entity_tracking option seems to fix it.

Possibly related to/is the same issue as #73?

[Twisted-Code]

I'm wondering if one of the mods in our pack interferes with the mixins in the package that this config enables. Is there a way to get a list, e.g. from the server log, of all mixins that have been applied to a given method? If so, that would be the first place I would look to isolate the issue.

[ishland]

The optimization assumes that only nearby entities can be visible to a player and therefore only tracks entities that are near a player. I'll try looking into this later.

Is there a way to get a list, e.g. from the server log, of all mixins that have been applied to a given method? If so, that would be the first place I would look to isolate the issue.

You can use -Dmixin.debug.export=true and decompile the class files in .mixin.out/class to figure it out.

[ishland]

Try this version and see if the problem is solved:
https://github.com/RelativityMC/VMP-fabric/actions/runs/13356730547