Godot Version
4.7.1
Question
I tried using Jolt physics for a car game. The car works fine, however if I use joints to attach RigidBody3Ds to the VehicleBody3D, they start floating away when the car moves. I tried using all sorts of different joints. This is not a problem in the default Godot 3D physics. The joints are supposed to be effectively fixed joints.
The reason I wanted to add these as separate rigid bodies is to simulate breakage and (in the case of the cabin) make it move slightly reactively to forces.
A video of the issue, with default Jolt3D options:
The Tree of the Vehicle:
CabToVehicleJoint:
When increasing the Jolt Physics 3D Velocity and Position steps to 32 and 24 respectively, it gets better, but the rigid bodies still ‘run away’ from from the vehicle. I tried doubling this too to no avail.
Video of the simulation with adjusted Jolt3D parameters:
Video of what the same setup looks like with GodotPhysics3D:
I tried changing more properties, such as the Baumgarte Stabilisation Factor, but that did not seem to change simulation significantly, except at high values where simulation got very buggy (to be expected - it’s mentioned in the docs).
Any suggestions how I could continue? Am I missing some settings? Is this a bug with Jolt3D?