rigidbody.MovePosition laggy

Hi, I am using rigidbody movePosition for movig player and it looks very laggy. The documentation says that enable Interpolate is required on rigidbody inspector for smooth moving but it doesn't fix the issue.
Camera follow the player with Vector3.Lerp or Vector3.SmoothDump and I see smooth translation of the environment on the screen but body is very stuttering.
Is there solution for the issue?
The moving body class:

Code (CSharp):

1. public class TestMovePong : MonoBehaviour
2. {
3.     [SerializeField] private Rigidbody _rigidbody = default;
4.  
5.     private float _currentSpeed = 15f;
6.     private Vector3 _direction = Vector3.right;
7.     private float _pong;
8.  
9.     private void Update()
10.     {
11.         _pong = Mathf.PingPong(Time.time, 2);
12.         _pong -= 1;
13.     }
14.  
15.     private void FixedUpdate()
16.     {
17.         _rigidbody.MovePosition(transform.position + _direction * (_pong * Time.fixedDeltaTime * _currentSpeed));
18.     }
19. }

Moving camera class:

Code (CSharp):

1. public class TestFollowTarget : MonoBehaviour
2. {
3.     [SerializeField] private Transform _target = default;
4.     [SerializeField] private float _currentSpeed = 10f;
5.     [SerializeField] private float _lerpTime = 1;
6.  
7.     private Vector3 _moveLerp;
8.     private float _zOffset;
9.  
10.     private void Start() =>
11.         _zOffset = (_target.position - transform.position).z;
12.  
13.  
14.     private void LateUpdate()
15.     {
16.         // transform.position =
17.         //     Vector3.SmoothDamp(transform.position, _target.position - Vector3.forward * _zOffset,
18.         //         ref _moveLerp, Time.deltaTime * _currentSpeed * _lerpTime);
19.  
20.         transform.position = Vector3.Lerp(transform.position, _target.position - Vector3.forward * _zOffset,
21.             Time.deltaTime * _currentSpeed * _lerpTime);
22.     }
23. }

 

Enabling "isKinematic" fixes the issue but I need body to be non kinematic as I need to use AddForce to emulate gravity and impact.

 

In non-kinematic bodies you should use AddForce only. Using MovePosition means overriding the results of the physics solver, so both you and the solver are giving contradictory positions to the rigidbody, hence the jittering.

Note that you may use AddForce with ForceMode.VelocityChange to impose a velocity to the kinematic body. For example:

Code (CSharp):

1. rigidbody.AddForce (expectedVelocity - rigidbody.velocity, ForceMode.VelocityChange)

You could compute expectedVelocity starting with the current velocity (rigidbody.velocity) and considering your imposed direction and speed (i.e. "speed should be n in the x axis" - that's plain vector math).

 

Eh? You meant in non-kinematic bodies?

 

non-kinematic => add force
kinematic => MovePosition and also enable interpolation for smooth movement.

 

I think you shouldn't use MovePosition if you want your player to be affected by other forces, because as i understand, move position is almost the same as just manually setting your rigidbody position every frame. Maybe that's what is causing the jitter, because some force is applied but your moveposition sets the position back and so on

 

Yes, sorry. Fixed.