Players freezing/teleporting when walking at a far distance

Bug Reports Engine Bugs
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As your can see in the above attached clips, player characters who are far away tend to have an effect where they freeze for a second or so, and then teleport, not having a smooth and consistent walk velocity at all.

This is a very bad for pvp games like this one.

Here’s the affected game in question: Armored Patrol v9.0 | Play on Roblox

One of the suspicions was it could be related to the animation and how it sets C0/C1 of the characters joints including the RootJoint, every once in a while, however even then it doesn’t really match up to this bug.

The game may also potentially suffer from poor physics performance during peak gameplay, so it’s possible it could be tied to this too, but we’re not 100% and haven’t been able to find a way to address this bug either way

screenshots of microprofiler physics issues

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.ZIP containing micro profile HTML dump
MicroprofileHTML.zip (2.0 MB)

Expected behavior

I expect player movements, no matter the distance to be consistent and not lag behind or have this teleport effect, we also expect the physics to be much more forgiving then this, so we are hoping this bug report will also address this too

A private message is associated with this bug report

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log_9DA9D_microprofile_20260717-175635.zip (1.0 MB)

additional microprofiler dump missing from the linked MicroprofileHTML.zip (i’m the guy who recorded the videos)

i do have an uncapped framerate past 240fps, but seems like everyone encounters this issue regardless of frame rate, so i don’t think it’s that

it’s a bit hard to see in the video, but other assemblies like the tanks generally seem to replicate fine regardless of distance, it’s just these dang player characters

additionally, when moving closer to the player characters, the issue does resolve and player characters seem to replicate at an acceptable rate (until you move farther away again, then they become choppy), it makes me think it’s some sort of engine optimization

as for when this issue started, as far as i’m aware it’s been an issue for years at this point (not 100% sure on this, but i’ve been playing armored patrol for quite a while and i do remember it being annoying to hit my shots, but i just thought the player was lagging or something)

also, not sure if the PM provided a place file, but the scripts that set up that “C0/C1 animation” talked about in the initial post are going to be “LsOrientC” (client-side) and “SsCharManagerB” (server-side, since C0/C1 do not replicate), we’ve also tried enabling/disabling “ImprovedPhysicsReplication” under the workspace, as well as switching to both adaptive timestepping and fixed via “PhysicsSteppingMethod”, adaptive timestepping reduced the server CPU usage a ton, but neither of those changes seem to have resolved the issue. let me know if the place file is needed, some of these microprofiler dumps may be before the time i enabled adaptive timestepping as well

potential duplicate of: Humanoid Replication Bottlenecking

EDIT: managed to re-pro it once in the place file by messing with the “Network Simulation” settings in studio, it may only happen if lots of vehicles are spawned in
basically just playtest using a server and 2 clients, mess with the network simulation settings to make some not-so-great conditions, try and spawn in a bunch of vehicles (can just open the dev console while playtesting the place file and run shared.physicsTest() a few times lol)

client 1 goes on red team (base around 0,0,0)
client 2 goes on blue team (a few thousand studs away from where client 1 is going to be)

on client 1, set workspace.CurrentCamera.CameraSubject to client 2’s character, then start moving on client 2, maybe spam equip and unequip tools and repeatedly press C while moving on client 2

ideally have 2 windows open side-by-side so you can see what client 1 sees, and control client 2 at the same time, in my re-pro, the animations like crouching and rifle aiming were visible, but client 2 remained stuck in the same place despite the animations and other network traffic evidently working just fine, exactly as the potential duplicate post and video show

it is difficult to re-pro though, it seems quite hit or miss…

another edit: tried disabling ImprovedPhysicsReplication, i seem to be noticing some of this “teleporting” on the vehicles now as well (i don’t believe i noticed this before with it on, it was just the players)
to be fair, when i noticed this vehicle issue, i was also in a distant server, so my ping wasn’t that great, i’ll turn ImprovedPhysicsReplication back on to see if the vehicles still “teleport” a bit

edit: yes, i do think ImprovedPhysicsReplication reduces/stops the vehicle “teleporting” i noticed while playing yesterday, player teleporting is still an issue regardless of what i set that at

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Still very much occurring

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Hey, thanks for posting! Re: the poor physics performance, I cracked open the microprofile that you attached and noticed a massive number of bodies/constraints being simulated:

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There are only 7 simulation islands, so there are 7 large groups of mechanisms somewhere in the world. Maybe objects aren’t being destroyed correctly?

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Hi. Thank you for the reply. Will notify the dev about this.

How about the player replication issue though? Is that tied to this? The player teleporting stuff at a far distance described in the post?

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Also I’ve been playing the game, server is running fine right now, yet this player replication/teleport issue still persists anyways. It’s been happening to others too: Humanoid Replication Bottlenecking

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Yeah, unfortunately I think this is one of those games that will need a raycast suspension of some sorts, there can be up to 1 prismatic constraint, 1 spring constraint and up to 3 hinge constraints per vehicle wheel, a vehicle might have up to 20 wheels or so

servers are 14 players and players are allowed 2 vehicles
if they exceed that, then an audit script starts deleting their older vehicles (it is an old script that was using :Remove on the vehicle’s model, just changed it to :Destroy)

players have network ownership of their vehicles if they’re driving them, it is set to the server if the vehicle isn’t occupied however

a few other things like crates may be simulated by the server occasionally (it’s set to auto afaik, so if there’s a player close enough it will be theirs), but crates are only one part and i wouldn’t expect more than 100 of those on the map

this game was made back in like 2014 so the vehicle models aren’t complex at all, it’s mainly just parts and wedgeparts welded together (though vehicle suspension was added in 2017), it’s not like there’s a ton of unions with their collision fidelity set as “PreciseConvexDecomposition”

Currently, I’m more concerned about the player teleporting bug, despite these horrible “Physics” spikes, the game actually remains surprisingly playable, since only a few frames will get huge spikes like that, most people seem to describe the game as running “fine”, except for the player teleporting bug, which is definitely a bit annoying in a PVP game like this

I wouldn’t worry about the physics thing right now, one thing at a time lol (sorry for cramming 2 things into 1 report)

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Ok, thanks for the info. Even with 28 tanks and 100 crates, that would only be about 600 rigid bodies, I think it would be good to audit your deletion code to make sure nothing is slipping through.

I’ll route this to networking since the player teleporting is the bigger concern. Thanks!

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yeah, the 8000 bodies seems pretty interesting, i’ll look into it

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Hi, just to make sure I understand the issue from the networking side.

We have a player teleporting issue when they are far away.

  • We may additionally have a vehicle teleporting issue as well, and ImprovedPhysicsReplication fixes this, so just player

Is the player teleporting issue an recent regression or it was never worked in the first place?

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as far as i’m aware, it’s a recent regression

another post i found experiencing a simillar issue gave a timeframe of 6/16:
Undocumented changes to replication with no options to modify or disable them is causing games to be dislike bombed (seems to be a duplicate post, their video looks very similar)

as far as the vehicle teleporting thing goes, i could’ve just been in a laggy server, i’ll disable ImprovedPhysicsReplication once again and play in an active server (it’s currently enabled, and i didn’t notice any vehicle “teleporting” while playing yesterday)

it’s gonna be a few hours before new servers with IPR off spawn, ill edit this post later

also, i assume the “ImprovedPhysicsReplication” property will eventually be removed and enabled forcefully for everyone? i don’t consider disabling IPR a permanent fix if that’s the case unfortunately

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another post i found experiencing a simillar issue gave a timeframe of 6/16:
Undocumented changes to replication with no options to modify or disable them is causing games to be dislike bombed (seems to be a duplicate post, their video looks very similar)

Yeah I am aware about that one, but that one indicates disabling ImprovedPhysicsReplication fixes their issue. I think the issue in this report happens with and without ImprovedPhysicsReplication?

also, i assume the “ImprovedPhysicsReplication” property will eventually be removed and enabled forcefully for everyone? i don’t consider disabling IPR a permanent fix if that’s the case unfortunately

Yeah, that’s correct. We are fixing all the issues.

So far I haven’t been able to locally repro this, if you happen to have an repro file locally, would mind share it? Thanks

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i’m waiting for new servers to spawn to confirm disabling IPR fixes the player teleporting bug
i can say, i did turn it off for a bit a few days ago, and didn’t notice any player “teleporting” going on while i was playing on that day, i did turn it back on later though and have been noticing it since.

re-proing it seems to be an absolute pain, i’ll try and PM a place file for the game, i re-proed it once in studio by messing with the network simulation settings to create some less-than-favorable conditions, then using 2 clients on opposite sides of the map (one client had their CameraSubject set to the far-away client), then i did notice some teleporting going on (weirdly, it can be intermittent)

i’m not sure if the teleporting issue only happens if the physics engine is under load or something, that might be the case, probably worth trying to apply some physics load before trying to re-pro

edit: not really quite sure if i can PM, the devforum seems to just give me a follow/unfollow button, did OP provide a place file in the PM?

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ok, i do think turning ImprovedPhysicsReplication OFF actually does fix the player teleporting issue (i could not repro the bug with IPR off)

but it seems turning IPR off causes the vehicles to teleport instead (at least that’s what i’ve noticed), it really is a “pick your poison” situation here…

i don’t consider turning IPR off to be a fix given that the property will be removed eventually and forced ON

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possibly related: noticed player teleporting in lumber tycoon 2, particularly in servers with players who have bases with lots of moving parts on conveyors (so probably quite a bit of physics load). never noticed any teleporting in that game until now.

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