Trailers desync

[Pirulax]

Describe the bug
erorr404 said:

Talidan and I were playing around with trucks and trailers today, and several times the trailers became desynced. For example, I saw his truck without the trailer, even though it was on his screen. When he detached it, it disappeared from his screen as well.

To reproduce
Just create a Towtruck, attach a vehicle to it and go on the Road, it'll desync

Screenshots
https://www.youtube.com/watch?v=XD2JX9hZV2U

Version
Even in the newest

Additional context
Mantis link: https://bugs.mtasa.com/view.php?id=1655

[Pirulax]

What I think would be a good solution to this is to just sync if it's towed or not, because, as seen in the video, something deataches the towed vehicle.

The issue with trailers it, that they detach after a time as well.

[Einheit-101]

Trailer sync is garbage even when a player is driving it, i have drivable trailers on my server and its ridiculous.

[PlatinMTA]

This is bound to the <unoccupied_vehicle_sync_interval/> setting on mtaserver.conf, the vehicle attached doesn't update as quickly as it should, so you can see the trailer like behind of the vehicle meanwhile the player driving it won't see anything different. At least that it's what I think the problem comes from.

[StifflersMom]

I made the linked video for describing some issues with <unoccupied_vehicle_sync_interval/>. The idea behind this things were to sync the towed vehicle even with puresync like the towing vehicle.
On our server, we had a extreme low unoccupied_vehicle_sync_interval ( somewhat between 50 and 70, it's out of the limit range but it was functional). Also we made a resource, which uses detachTrailerFromVehicle client side for everyone except the tower. This made the trailer / towed vehicle update it's position more accurate than MTA itself.
For some unknown reason, all this tricky things were broken with some 1.5.6-????? version. Now we have ALWAYS desynced towed vehicles, except for the tower (wromg positions, wrong angle, ...).
I was talking to some devs before and they said, the towing sync and it's procedures are somewhat messed up - So someone will make a miracle come true and fix this and become a hero for all times 👯‍♂️

[tederis]

I think, I have some progress in there
https://youtu.be/iFClCa_xaG4

[Citizen01]

Where is your branch tederis ?

[tederis]

Where is your branch tederis ?

It's still under development. The bug consists of two problems and I have fixed just one.

[tederis]

Unfortunately I have no time at the moment to continue the research. So I made a simple fix that didn't eliminate the source of a problem but made a trailer's behavior much more satisfactory.
It can be found at https://github.com/tederis/mtasa-blue/tree/trailers_fix
I think it's just a half measure so I didn't dare to made a PR.