MantisBT - Zandronum
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IDProjectCategoryView StatusDate SubmittedLast Update
0001682Zandronum[All Projects] Bugpublic2014-01-23 23:472015-06-10 19:47
ReporterLeonard 
Assigned To 
PrioritynormalSeveritytweakReproducibilityalways
StatusconfirmedResolutionopen 
PlatformMicrosoftOSWindowsOS VersionXP/Vista/7
Product Version1.2 
Target VersionFixed in Version 
Summary0001682: Floor_Waggle produces jittery lag online.
DescriptionI noticed this while playing jumpmaze.
Basically when jumping on a floor that waggles, you will get some kind of jittery lag as if you had a really high ping.
It happens mostly on the edges at high-ish speeds.

It's easy to reproduce on the example wad, just go fast and hold jump and try to jump on the edges.
Note that only the red (right) side uses floor_waggle, the blue one is just here to compare.
Steps To Reproduce-Host the example wad on a server where you ping atleast 50 (you can use your own with a ping emulator or just host it on best-ever/whatever server you want).
-Get in the red side.
-Jump around.
Additional Information
TagsNo tags attached.
Relationships
related to 0002294feedback  Very evident misprediction of movement on raising floors in general 
Attached Files? justtestingthings.wad (69,260) 2014-01-23 23:47
/tracker/file_download.php?file_id=1152&type=bug
? WaggleTest2.wad (9,557) 2014-02-13 19:50
/tracker/file_download.php?file_id=1163&type=bug
? WaggleTest3.wad (1,428) 2014-12-14 15:28
/tracker/file_download.php?file_id=1346&type=bug
Issue History
Date ModifiedUsernameFieldChange
2014-01-23 23:47LeonardNew Issue
2014-01-23 23:47LeonardFile Added: justtestingthings.wad
2014-01-25 12:08Torr SamahoNote Added: 0008130
2014-01-25 12:08Torr SamahoStatusnew => feedback
2014-01-25 15:07LeonardNote Added: 0008131
2014-01-25 15:07LeonardStatusfeedback => new
2014-02-13 19:50LeonardFile Added: WaggleTest2.wad
2014-02-13 19:51LeonardNote Added: 0008197
2014-02-13 20:11Torr SamahoNote Added: 0008198
2014-02-14 13:16ibm5155Note Added: 0008206
2014-04-11 02:12ArcoNote Added: 0008538
2014-04-11 02:12ArcoStatusnew => feedback
2014-07-31 23:40LeonardNote Added: 0010100
2014-07-31 23:40LeonardStatusfeedback => new
2014-12-14 15:28LeonardFile Added: WaggleTest3.wad
2014-12-14 15:32LeonardNote Added: 0011059
2015-01-10 14:48HypnotoadNote Added: 0011355
2015-01-10 15:55Torr SamahoNote Added: 0011356
2015-01-10 15:55Torr SamahoStatusnew => confirmed
2015-01-11 15:22Torr SamahoNote Added: 0011364
2015-06-10 19:47unknownnaRelationship addedrelated to 0002294

Notes
(0008130)
Torr Samaho   
2014-01-25 12:08   
I don't see any floor waggling in the example wad.
(0008131)
Leonard   
2014-01-25 15:07   
It's the red side. I just used a slow waggle to make it easier to jump on.
(0008197)
Leonard   
2014-02-13 19:51   
Uploaded a new test wad with a stronger waggle although that was not needed at all but since people seemed to not care once again..
(0008198)
Torr Samaho   
2014-02-13 20:11   
What do you mean with "since people seemed to not care once again"?
(0008206)
ibm5155   
2014-02-14 13:16   
"since people seemed to not care once again"
"Supporters: ibm5155"
'-'

I can't help, the only thing I know for now is copy and paste commits from zdoom to zan and fix some simple problems :B
(0008538)
Arco   
2014-04-11 02:12   
I cannot reproduce the jittery lag as written in the ticket. Are you doing something else that may be doing this?
(0010100)
Leonard   
2014-07-31 23:40   
I am sorry that it took me so long to respond.
I re-tested it and apparently it doesn't happen as much as it did before.
But it's still there. I suggest hosting a server with the second test-wad I made (It seems to be more likely on this one) and connecting to it with gamersproxy with just an emulated ping of 100 and then simply holding +jump on one of the waggling floors. Within 10 seconds at least I get the desync.
(0011059)
Leonard   
2014-12-14 15:32   
Uploaded an even better testing wad (WaggleTest3.wad)
Just load the map on a server and keep pressing +jump and the effect immediately happens.
Switch between an emulated 0/200 ping on your local server and you will notice the difference and it's even more noticeable with chasecam on.
Also it seems that this is caused by the client's movement prediction because when setting cl_predict_players to 0, the effect disappears completely.
(0011355)
Hypnotoad   
2015-01-10 14:48   
Just thought I'd post to confirm this, numerous people have complained about very jittery waggle floors when ping is more than 100 or so, particularly problematic on jumpmaze.
(0011356)
Torr Samaho   
2015-01-10 15:55   
I can confirm that WaggleTest3.wad with an emulated ping of 200 allows to easily reproduce this effect.
(0011364)
Torr Samaho   
2015-01-11 15:22   
I had a look and I'm pretty sure I know what's going wrong. While predicting, the client assumes that sector heights do not change during the prediction window. There are some additions that take care of moving floors, but these workarounds cannot cover the case where a moving floor changes its direction during the prediction window.

So this is more of a missing prediction feature than a bug. Fixing requires to take into account the effect of the waggle during the prediction. Unfortunately, this is not trivial.