Creeps 'teleporting' in replays | Screeps | Page 1

bleak crescent Jan 11, 2026, 8:12 AM

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We have received several reports that there are visual glitches in replays when creep position is visually stuck and refreshed only when the next 100-tick chunk is loaded.

Here are a few questions that would help us to troubleshoot this:

How often this issue is reproduced? Every replay?
Does it happen only in your games when the console and Visuals are available, or in shared replays of other players too?
If it happens in your replays only, does closing the console help?
If it happens in other players replays, does it happen in the same replay again if you start it over? Please share a link to the replay.
Are all objects stuck on this tick, or this affects only the state of one creep?
Could you record a video with this behavior?

tardy bridge Jan 11, 2026, 8:25 AM

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Almost every replay. Some very simple ones E.g. 1 creep vs System, I don't detect it.
It happens with other players too.
Closing the console makes no difference.
Closing the replay and re-opening it reduces the frequency and severity, but closing Arena and reopening the same one has the same behaviour.
All objects are frozen for somewhere between 0 and sometimes up to 10 seconds. As far as I can tell, always on 100-tick boundaries.
I'll try.

onyx quest Jan 11, 2026, 8:27 AM

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every replay
yes, in shared replays of other players too
no, it doesn't matter if console opened or minimized
for my replays: it happens only on first playback of same opened replay; if I for example test 2x opponents, I can watch replay1, replay2, replay1. First playback lags every time, replay1 lagged when played first time, now i've opened replay2 and its first playback is lagging, and then I've opened replay1 again its first playback is lagging again

for shared replays: I've tested the border of tick 99-101, when I first encountered it I got the lag. Then when I scrolled back, and played again, got no lag. But when reaching 199-201 border i got lag again. Every first encounter or %100tick border lags.

switching shared replays back and forth appears to preserve old replay playback tick state. If I leave the state on lets say 150, then scroll it back to cross 100 again, this 100 will not lag. As it apparently preloaded. Yet if before switching back and forth I scroll it to lets say 50, upon return and continue playing 99-101 will lag again.

TLDR: every %100===0 on every unique replay open hangs. Test it with 20ticks/sec for better effect.

if affects state of every creep on the map. Visuals are not stuck though.
-; I don't actually believe you can not reproduce it, since even very low resolution no gpu/cpu-bound gameplay still lags; can you record a video of not reproducing it? since clicking "watch" up to watching it run? 20ticks/sec to make sure.

tardy bridge Jan 11, 2026, 8:31 AM

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I suspect it may depend upon network latency, and a low-latency connection to the server may not show the effect. (I'm in Australia)

bleak crescent Jan 11, 2026, 8:31 AM

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I'm watching replays of different players in different arenas right now, can't reproduce this behavior. Creeps are moving correctly around 100-tick boundaries.

Any links to shared replays where this is reproduced?

tardy bridge Jan 11, 2026, 8:31 AM

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https://arena.screeps.com/game/2SZ86JYBF5

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(Which was pretty much the first shared replay I found)

onyx quest Jan 11, 2026, 8:32 AM

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I can not seem to be able to copy a link, just the first replay I've opened:

tardy bridge Jan 11, 2026, 8:32 AM

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I've captured a video, but it doesn't show the effect at its worst - just a second or so.

bleak crescent Jan 11, 2026, 8:33 AM

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Yeah, this has nothing to do with GPU, CPU and rendering, it's either a network client/server issue, or some bug in the ticks loading code that makes this 100-tick chunk corrupted.

tardy bridge Jan 11, 2026, 8:34 AM

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My suspicion is that the client keeps "ticking" at constant rate whether it has data from the network or not.

onyx quest Jan 11, 2026, 8:34 AM

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I must remind you, that if upon opening a new replay you grab the scroll-progress-bar and drag it through the duration, then move it back to the beginnig, there will be no lags. Encountering playback locations for first time properly loads it. Be it during real playback, or by dragging through it, for states to be loaded on the field statically.

tardy bridge Jan 11, 2026, 8:34 AM

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So when the network data does arrive, it "catches up" and teleports everything by up to 20-50 ticks.

onyx quest Jan 11, 2026, 8:35 AM

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tardy bridge My suspicion is that the client keeps "ticking" at constant rate whether it has ...

I would assume no network should be involved at this stage, it would be weird to load even ready-made shared replays in chunks instead of full in 1go.

bleak crescent Jan 11, 2026, 8:35 AM

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What if you manually advance by 1 tick and give it a few seconds every time, what happens around the 100-tick boundary?

tardy bridge Jan 11, 2026, 8:35 AM

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It definitely does load in 100-tick chunks. You can see them come in through the network.

onyx quest Jan 11, 2026, 8:36 AM

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bleak crescent What if you manually advance by 1 tick and give it a few seconds every time, wha...

haha funny YES!

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controls react to my manual clicks, numbers update realtime, only by the time I have clicked ~107 does creep positions gets updated. Same lag.

bleak crescent Jan 11, 2026, 8:37 AM

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onyx quest I would assume no network should be involved at this stage, it would be weird to...

The replay is loaded by 100 ticks at the current position, even when you rewind to the end of the game. If you move to tick 1500, it will load 1500-1600, but won't load anything before 1500

onyx quest Jan 11, 2026, 8:38 AM

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"loaded" as in "decoded some blob of json data that is already in local memory -- into an actionable objects state".
Or is pwk correct and it really queries remote server 20 times per 2000 tick replay every time?!

bleak crescent Jan 11, 2026, 8:40 AM

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Loaded as in loaded from the server, Pwk is correct

tardy bridge Jan 11, 2026, 8:41 AM

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It would probably resolve 99% of the issue if it prefetched the next chunk while playing the current one.

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(If one is available to be prefetched)

bleak crescent Jan 11, 2026, 8:41 AM

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It tries to do that currently

tardy bridge Jan 11, 2026, 8:42 AM

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Really? I'm not seeing that happen.

onyx quest Jan 11, 2026, 8:42 AM

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I'm trying to send you a PM @bleak crescent add me as friend on discord

tardy bridge Jan 11, 2026, 8:43 AM

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If I'm at tick 600 and advance then I get a definite pause (currently about 1.5-2 seconds) before it shows tick 601.

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If it was preloaded I would expect it to be effectively instant.

onyx quest Jan 11, 2026, 8:44 AM

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indeed, when reproducing it manually with 1tick steps, I can stop at tick99 for a minute, then start clicking and it will still lag when crossing %100

tardy bridge Jan 11, 2026, 8:44 AM

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(and it is effectively instant if I step tick backward then forward again)

bleak crescent Jan 11, 2026, 8:44 AM

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onyx quest I'm trying to send you a PM <@273043058755502081> add me as friend on discord

Sorry I don't use PM in Discord

onyx quest Jan 11, 2026, 8:44 AM

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so it's not network speed or something, it's lack of intent to preload

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I wanted to send you my network info, np if you don't want it. We figured it's lack of intent to preload.

bleak crescent Jan 11, 2026, 8:45 AM

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Ok just to confirm: if you are at tick x00, you advance by 1 tick, you wait some long enough time, it loads the tick x01 successfully without issues?

onyx quest Jan 11, 2026, 8:46 AM

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99->100 just checked, lags.

tardy bridge Jan 11, 2026, 8:46 AM

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If I single-step from x00 to x01, there's pause, but it eventually loads. If it's on "play" mode, the playback doesn't pause, it just teleports everything when it loads.

onyx quest Jan 11, 2026, 8:46 AM

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will see the 101st

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no, it appears to lag 100->101

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so it was not 99-100 :)

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101->102 doesn't lag

bleak crescent Jan 11, 2026, 8:48 AM

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But 100-101 eventually loads if you wait?

onyx quest Jan 11, 2026, 8:48 AM

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bleak crescent But 100-101 eventually loads if you wait?

yes, I have time to click like 10 times until it's updated

tardy bridge Jan 11, 2026, 8:48 AM

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If my play rate is 5 tick/s then it will skip 5-15 ticks (depending upon load time) except that oddly visuals may update during that time, sometimes.

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But yeah, if single-stepping then 101 loads. It just gets skipped in a continuous playback.

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The more creeps and visual, the longer the skips/pauses appear to be.

bleak crescent Jan 11, 2026, 8:50 AM

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Something is wrong with the preload indeed

onyx quest Jan 11, 2026, 8:51 AM

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Lol by the way, if our assumption it's networking is correct, how the fuck my Visuals are being updated real time every time (have last time checked like a week ago; creeps froze; Visuals kept updating)

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visuals are only-clientside?!

tardy bridge Jan 11, 2026, 8:51 AM

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Yes, it's weird that visuals often render during the "pauses" when creeps don't update.

onyx quest Jan 11, 2026, 8:51 AM

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nah, sounds like nonsense

bleak crescent Jan 11, 2026, 8:52 AM

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Visuals, console and game objects are 3 separate streams of websocket data

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This is why I asked about other players' shared replays because they have only 1 stream

tardy bridge Jan 11, 2026, 8:52 AM

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It's just weird that I never see visuals paused with creeps updating. Just creeps paused with visuals updating.

onyx quest Jan 11, 2026, 8:53 AM

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console ticks never freeze
visuals never freeze
creeps freeze on %100

bleak crescent Jan 11, 2026, 8:53 AM

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Less data for visuals

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We'll try to fix the preload and deploy to a debug branch on Steam

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Keep in touch

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Thanks for your help with troubleshooting

bleak crescent Jan 11, 2026, 10:19 AM

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Could you please install an update from the preview beta branch on Steam and check does it work better for you?

tardy bridge Jan 11, 2026, 10:33 AM

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Will give it a go!

onyx quest Jan 11, 2026, 10:33 AM

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I did. I can not click on Test or on shared replays or on Fame or on Rated play. Can not test. Both with my dpi compatibility on and off.
Can play tutorial, in tutorial it doesn't appear to be lagging. But I don't remember if it was lagging previously in tutorial.

tardy bridge Jan 11, 2026, 10:34 AM

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Oh, that's much smoother for me.

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Playback went straight through the chunk boundary without pausing, and creeps were moving. I verified that when single-stepping backward into a chunk I hadn't seen, it did pause.

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Single-stepping forward into a chunk I hadn't seen didn't pause.

onyx quest Jan 11, 2026, 10:38 AM

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"I verified that when single-stepping backward into a chunk I hadn't seen, it did pause."
lol

tardy bridge Jan 11, 2026, 10:39 AM

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Yeah, tested that to make sure that it was preload and not just some fluke network conditions.

onyx quest Jan 11, 2026, 10:44 AM

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onyx quest I did. I can not click on Test or on shared replays or on Fame or on Rated play....

disabling windows scaling doesn't help, changing screen resolution to 1920x1080 doesn't help, gg I guess

bleak crescent Jan 11, 2026, 10:44 AM

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Do animations on the main screen work?

Do arena cards react on mouse hover?

Do Rating, Test, and Fame buttons react on mouse hover?

bleak crescent Jan 11, 2026, 10:45 AM

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onyx quest disabling windows scaling doesn't help, changing screen resolution to 1920x1080 ...

Do you restart the game client after these changes?

onyx quest Jan 11, 2026, 10:46 AM

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yes I did restart game client and checked it's not ran as a process, before running it again

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i did not restart windows
i did not restart steam

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background animation doesn't happen. The only thing that moves is the big icon of the arena, its animation is played like usual. The rest doesn't react doesn't move.

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whole top menu works like it should. Tutorial works like it should.

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console output is as usual:

ScreepsArena>
(node:12345) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.
(Use `screeps_arena --trace-deprecation ...` to show where the warning was created)
123.1 1 1280 719 {
  accelerometerSupport: 'unknown',
  bounds: { x: 0, y: 0, width: 1280, height: 800 },
  colorDepth: 24,
  colorSpace: '{primaries:BT709, transfer:SRGB, matrix:RGB, range:FULL}',
  depthPerComponent: 8,
  detected: true,
  displayFrequency: 60,
  id: 12345,
  internal: true,
  label: '',
  maximumCursorSize: { width: 0, height: 0 },
  monochrome: false,
  nativeOrigin: { x: 0, y: 0 },
  rotation: 0,
  size: { width: 1280, height: 800 },
  workArea: { x: 0, y: 0, width: 1280, height: 719 },
  touchSupport: 'unknown'
}
123.2 1 1
GET_STEAM_SESSION_TICKET
Setting breakpad minidump AppID = 12345
SteamInternal_SetMinidumpSteamID:  Caching Steam ID:  12345 [API loaded no]

bleak crescent Jan 11, 2026, 11:41 AM

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OK there was a bug with handling mouse events. Please install an update and try again

onyx quest Jan 11, 2026, 11:45 AM

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switched from main to preview and installed update
nothing changed, UI doesn't work

bleak crescent Jan 11, 2026, 11:46 AM

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Does it show version 1.0.8 in the bottom left corner of the game window?

onyx quest Jan 11, 2026, 11:47 AM

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restarted steam and repeated main->preview change. Now it works.

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replay playback doesn't appear to be lagging as well

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no, it shows 1.0.7 :)

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yet my own replays, and shared replays as well don't lag

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manually 1stepping backwards does lag like it used to, when crossing %100 for the segments never before loaded

bleak crescent Jan 11, 2026, 11:54 AM

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OK so the preload seems to be fixed now, very nice

onyx quest Jan 11, 2026, 11:55 AM

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this is asking for more than could have hoped before:

when I clicked and started watching not-yet-finished replay, it lags every %100 again: this time every time duration gets +100 added

bleak crescent Jan 11, 2026, 11:55 AM

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yeah because the preload can't work while there is nothing to preload yet

onyx quest Jan 11, 2026, 11:56 AM

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no, the current watch state is at let's say 340/1200, and it lags when it changes 340/1200 -> 340/1300

bleak crescent Jan 11, 2026, 11:57 AM

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it didn't happen before?

onyx quest Jan 11, 2026, 11:57 AM

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before it lagged even when it's totally loaded, so I never checked :)

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i'll switch to main to see

bleak crescent Jan 11, 2026, 11:58 AM

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@tardy bridge do you have this behavior?

onyx quest Jan 11, 2026, 11:59 AM

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yes I'm on main. It gets teleported like this (the one you've fixed in Preview)

tardy bridge Jan 11, 2026, 12:00 PM

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Updating now...

onyx quest Jan 11, 2026, 12:01 PM

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by the way, since now I know it's websocket streams, separate for console and stuff...

when launching a match, and then prematurely stopping it, and then trying to watch a replay, nothing gets printed to that prematurely-stopped game console.

tardy bridge Jan 11, 2026, 12:02 PM

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Everything looks normal here, background animations are running etc.

onyx quest Jan 11, 2026, 12:02 PM

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bleak crescent it didn't happen before?

yes, on main it lags twice: once each %100 of current play time, and once each +100 of right bound.

bleak crescent Jan 11, 2026, 12:02 PM

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onyx quest no, the current watch state is at let's say 340/1200, and it lags when it change...

@tardy bridge I mean this

onyx quest Jan 11, 2026, 12:02 PM

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tardy bridge Everything looks normal here, background animations are running etc.

that one was already fixed.

tardy bridge Jan 11, 2026, 12:03 PM

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Oh okay. I haven't been at my computer for the past hour or so.

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Oh, is this about matches in progress?

bleak crescent Jan 11, 2026, 12:04 PM

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yes

tardy bridge Jan 11, 2026, 12:04 PM

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I'll fire one up

bleak crescent Jan 11, 2026, 12:04 PM

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Is this lag just a UI slowdown, or it teleports creeps as well?

onyx quest Jan 11, 2026, 12:05 PM

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this one is obviously not as important and urgent as the one you've fixed, Артём. Nice to have but it's ok.

tardy bridge Jan 11, 2026, 12:05 PM

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Oh hmm, I'll try one that doesn't reach the end in a couple of seconds 😉

bleak crescent Jan 11, 2026, 12:06 PM

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if it teleports creeps, it seems important. if it's simply a slowdown, then that's something else

tardy bridge Jan 11, 2026, 12:07 PM

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In a Construct and Control test game, it lags the UI for about 0.5-1 seconds when each new chunk becomes available, but everything pauses no teleports.

onyx quest Jan 11, 2026, 12:07 PM

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it's hard to distinguish on main with all this lags and teleports. Switching to preview..

tardy bridge Jan 11, 2026, 12:09 PM

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Yes, it's definitely just a slowdown (and the ticks available counter ticks up while it's loading).

onyx quest Jan 11, 2026, 12:10 PM

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getting +100 right bound teleports, about this much (two different teleport distances). It's less than the original preload distance teleport.

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20 ticks/sec

tardy bridge Jan 11, 2026, 12:11 PM

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In my test games (with not a lot of creeps in the map) there is a bit of "catch-up" burst or movement that's faster than usual, almost a teleport, but not the huge teleports that the missing preload caused.

onyx quest Jan 11, 2026, 12:12 PM

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ticks ui continue to run smoothly while this hang happens. Just like in first fixed case.

bleak crescent Jan 11, 2026, 12:12 PM

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Very well then. We'll continue working on other performance-related stuff, but regarding this immediate issue with chunk preloading - I think we can consider it closed.

onyx quest Jan 11, 2026, 12:16 PM

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Trying to guess why would creeps-UI(not ticks UI) hang while server got increased right bound.. I can't come up with an idea.
You say client only preloads nearby frames, so 340/1200->340/1300 wouldn't make client load that new 1200-1300 chunk. Then, it's not ~399 where server lag may slow down getting new portion, client already has all the data to keep showing 340->350... What the fuck lags then?! :)

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except... the right-bound +100 is increased not with a +100 step, it's increased gradually +1-2-3-4-5...-100. This interface operation takes time. Maybe this loop of visual increase of right bound is performed in main/creeps interface thread, stopping all creep drawing?!

bleak crescent Jan 11, 2026, 12:18 PM

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Yes, there is something else being triggered in that case, needs investigating

onyx quest Jan 11, 2026, 12:20 PM

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lol by the end of this bugfixes who knows maybe SC:A will not lag at all, even for 4k display :)

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only way I know to make stuff lag on modern hardware is to make a while{} loop somewhere without clear boundaries like "only 60 times per second". Or to render some arcane 3d which is not the case.

bleak crescent Jan 11, 2026, 12:22 PM

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by the way, does preview branch work better for you with hidpi enabled?

onyx quest Jan 11, 2026, 12:31 PM

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I don't actually know. Please remind me, what should I expect?

when I enable compatibility-thing, it keeps low app resolution, very-small close to unusable cursor. Nothing appear to have changed.
when disable compatibility, running it stock default (win10, 4k, 300% scale), logo while game loads lags just as much as it used to. It's a fucking letters on a black background. Please don't lag!!
yes, I did a fallback to main and see the difference: edges of letters for like "test" and its graphics not as crisp on preview. Feels non-retina, blurry. And it lags obviously not as much.
Still not as good enabling my compatibility dpi.

You've improved it for me, and you've broken it for everyone with retina who has a better hardware :) And I intend to keep using my compatibility dpi to keep it more ugly / more fast.

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only thing that I envy for the new version is big visible cursor. I don't have it with compatibility dpi.

bleak crescent Jan 11, 2026, 12:38 PM

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We don't care about the loading splash screen performance. It is lagging not because of any issues, but just because it is actually loading the app, and the main browser thread is busy. Just ignore this, we are not going to do anything related to the loading splash screen. And it's not an indicator of anything.

The optimization in preview had two parts: 1) limiting dpi ratio to 1.5 because 2 and 3 is maybe an overkill in this case without clear benefits, 1.5 looks crisp enough, 2) limiting the internal animation frame rate to save some CPU cycles. Thepreview branch should perform with better GPU and CPU usage and higher resulting game client FPS on both low-dpi and high-dpi setups, but most notable on high-dpi.

onyx quest Jan 11, 2026, 12:41 PM

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"it is actually loading the app, and the main browser thread is busy"
when in dpi compatibility (lower resolution) it beautifully bundles letters into a word, and C rotates smoothly, and __ blinking. First impression matters :)

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your new dpi 1.5 doesn't seem to apply to loading screen, that screeps logo looks retina-crisp, like x3. That's what I'm reporting.

bleak crescent Jan 11, 2026, 12:42 PM

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that's correct, there were no changes on the loading screen

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as well as in many other UI elements and texts. only animated graphical elements were updated

onyx quest Jan 11, 2026, 12:43 PM

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yeah, Preview looks good. I haven't actually noticed I was without my compatibility-dpi, it lags more than compatibility-dpi, but it's not uncomfortable in Preview. Great.

bleak crescent Jan 11, 2026, 12:48 PM

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glad to know!

onyx quest Jan 11, 2026, 12:48 PM

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stock main:

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stock preview:

#Creeps 'teleporting' in replays