Roextended Project

UPDATE 25/07/2024: The info in this post applies to ATS/ETS2 game versions 1.36 to 1.49 only.

This, i suspect, has no impact on Gsync, Freesync or vsync off setups.

This is a frame time fix and not a frame rate fix.
If your vsync fps are constantly dropping below the vsync level then this won't / can't fix that problem.

With vsync on, when you drive around the game world the driving motion will randomly, but suddenly, slow down and then rapidly speed back up. Repeating this for a few seconds or so making you feel like you are driving a frog down the road or "rubber banding" effect.
The framerate isn't dropping below vsync level at these moments.
This is not a stuttering or freezing issue, it's a frametime issue.
Turning vsync off solves that issue but then you have to put up with screen tearing.

If the above description sounds familiar to you, then you can try this. Otherwise this solution isn't for you.

In the games global config.cfg file there's this line:-
uset t_averaging_window_length "20"
That's the number of the past frames used to calculate the current frame duration.
SCS info on that here: https://modding.scssoft.com/wiki/Docume ... _variables

Setting this to twice your current vsync framerate should fix this rubber banding motion.
So, if you have vsync on and have 60fps, then set it to 120.
That'll use 2 seconds worth of past frames to give the current frame a much more stable average value for it's frametime.

UPDATE 19/04/2022
Since game version 1.40 (the new "far too demanding" lighting system) I've had to change my value from 60 to 150.
So for me, that's now 5x my vsync fps (30 fps) instead of my original 2x used in 1.36/1.37/1.38/1.39.
If you still get "rubber banding" after increasing this value... just keep testing with higher multiples of your vsync fps.

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My story to explain why i know it works for me:
Ever since DX11 was added to both games, i've been unable to play them in 64 bit mode due to the above "rubber banding" driving motion issue.
My solution has always been to run both games in 32 bit mode, i don't use mods, whilst also using 3dOverrider.exe to provide a triple buffer for 32 bit games. Perfect.

After each game update i recheck 64 bit to find the problem hasn't gone away, for me at least.

I have used config.cfg vsync "2" (economy mode in game menu) to lock to 30 fps for many years.
I now set config.cfg - uset t_averaging_window_length "60".
Having now driven all over ATS and ETS2 worlds (1.37), i've had no more rubber banding issues since setting that to "60".

As a double check, i set it back to default 20 and rubber banding is straight back.

Q6600 @ 3.3ghz, 8 gig ram, GTX760 2 gig, 3840x1024 & Win 7 x64.
I use 60hz with 'vsync 2' & 30 fps because i use NPI AA (DX9 and now DX11) and NPI AA drops my frames to below 60 at times causing stutters/slow downs.
So 30 fps is best for me and has always been smooth in 32 bit mode, but now i run in 64 bit mode!

Example:
In this pic you'll see 10 frames displayed one after another for a 1 second time period. 10 fps.
Each frame has 0.1 of a second to display itself.
. .
1 = Choppy motion caused by frames being produced at different speeds within each 0.1 interval.

2 = Very choppy motion caused by most of the frames being produced very quickly and leaving a gap.

3 = Smooth motion. All frames produced at a constant rate.

All 3 examples run at a constant 10 fps, no fps drops, but 2 will show a slow down/speed up motion, but it still produces 10 fps.


Info from other users when using this:
viewtopic.php?p=27427#p27427

@JHTrucker

I can confirm this too, but I haven't had these severe "rubber banding" effects.
My experience is though, that the frame creation gets smoother and gives that
feeling to the whole rendering scheme. I've already advised people around me
to use a much higher value than the default 20. I will probably also add this to
the first post of the NPI topic to use for game enhancement.

Thank you for all your brilliant ideas for these games, ETS2 and ATS!

@BenganJ - I didn't want this hidden in the NPI post as it's for everyone, with this issue, to use and not NPI AA related.
Hence why i created this post.

If you google "ets2 rubber banding" you'll see this is a thing that people like me suffer from.
Hopefully some will see this post and try it.

Thanks.

@JHTrucker

Right, I know very well, that this is a common problem and I have experienced it too,
just not lately! The NPI topic is not a pure NPI or AA topic from the beginning and also
contain plain graphics enhancements and I think this definitely is one of these. This
topic is definitely also valid as it contain also the explanation of the problem and the
solution.

＠JHTrucker

I always appreciate your help.

I have only one question.
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Setting this to twice your current vsync framerate should fix this rubber banding motion.
So, if you have vsync on and have 60fps, then set it to 120.
That'll use 2 seconds worth of past frames to give the current frame a much more stable average value for it's frametime.
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Is this twice the vertical sync you have set?

My current setting is 144hz with Vsync=1. (Average of 95 fps in the game)
Especially this phenomenon occurs when 72hz is specified with Vsync=2.
(Deceleration and acceleration occur on the native WQHD screen)
Please tell me a better setting without DSR.

@clear F1

I would suggest that you set VSync=2 to get a FPS limit of 72 and then you set or you can also test VSync=3 for a FPS limit of 48 and set Then report your experience here, please!

As a result of trying many settings, none of them was problematic, and finally I ran about 100 km with the following settings, but it looks good.

desktop: 2560x1440 120Hz
config.cfg: r_vsync "2", t_averaging_window_length "120"
In-game: 60fps
g-sync: on

@clear F1

So this is the first time, with the new monitor, you could run with r_vsync "2" without problems?
I'm not sure though that GSync is a good thing in this case, but let us wait on JHTrucker's opinion
on that!

When I tried it before, Vsync=2 or 3 had exactly this phenomenon (rubber banding). There was no problem with this setting.

@clear F1

Good then, enjoy!