We recently implemented a vehicle system in our game Project 12, we experienced bugs relating to our ragdoll system and vehicle seats (specifically humanoid state thrashing that left humanoids stuck in seats). We decided to fix this by converting our vehicle system to use a custom seat implementation. We tested this thoroughly in studio, and this worked. However, yesterday we began to notice that vehicles on live servers were not behaving in the same way as they do in studio.
Here is a video of the vehicle behaving normally in studio
External MediaHere is a video of the vehicle behaving abnormally in a live server.
External MediaAs you can see, the acceleration is slow, and this occurs on every single vehicle in some way, whether that be poor acceleration, unusual bouncing of suspension etc.
My initial idea was to disable adaptive physics stepping as I thought that may be the cause, however this made no change.
The issue is not entirely consistent; we had some servers yesterday where vehicles behaved entirely normally.
To me it appears as if the friction in the physics simulation is not consistent between studio and live servers, and I assume there is some clause in the humanoid vehicle seat logic which fixes this, however this probably signals a larger issue.
I’ve tried to find some workarounds such as adding a fake unused vehicle seat in and giving it an occupant; however, this does not work.
