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+# Fix Physics Jitter
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+
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+<span class="badge text-bg-primary">Beginner</span>
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+<span class="badge text-bg-success">Programmer</span>
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+
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+In Stride there is no default smoothing applied to Entities that are attached to physics entities. This can cause a noticable jitter especially if you have the camera attached to a character component.
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+In this tutorial we will look at whats needed to add smoothing to an entity through a SyncScript.
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+
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+>[!Note]
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+>You can also decrease the `Fixed Time Step` in the physics configuration, for example change it from `0.016667` to `0.008` for more accurate physics but this will be more expensive on the CPU.
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+
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+## Code to handle smoothing between 2 entities
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+This should be all thats needed to attach 2 entities together. Make sure that you unparent the entity you are trying to smooth or else the transofrm processor will override this script.
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+```cs
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+[ComponentCategory("Utils")]
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+[DataContract("SmoothFollowAndRotate")]
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+public class SmoothFollowAndRotate : SyncScript
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+{
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+ public Entity EntityToFollow { get; set; }
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+ public float Speed { get; set; } = 1;
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+
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+ public override void Update()
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+ {
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+ var deltaTime = (float)Game.UpdateTime.Elapsed.TotalSeconds;
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+ var currentPosition = Entity.Transform.Position;
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+ var currentRotation = Entity.Transform.Rotation;
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+
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+ var lerpSpeed = 1f - MathF.Exp(-Speed * deltaTime);
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+
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+ EntityToFollow.Transform.GetWorldTransformation(out var otherPosition, out var otherRotation, out var _);
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+
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+ var newPosition = Vector3.Lerp(currentPosition, otherPosition, lerpSpeed);
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+ Entity.Transform.Position = newPosition;
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+
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+ Quaternion.Slerp(ref currentRotation, ref otherRotation, lerpSpeed, out var newRotation);
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+ Entity.Transform.Rotation = newRotation;
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+ }
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+}
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+```
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+
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+## Example Usage
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+For this example we will modify the First Person Shooter Template.
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+
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+Step 1: Detach the camera from the Physics entity
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+
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+Step 2: Remove the FPS camera script from the camera
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+
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+Step 3: create a new entity as a child to the character body
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+
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+Step 4: Add the FPS script to the new entity
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+
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+Step 5: change the following code since they reference the CameraComponent directly
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+
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+### PlayerInput.cs
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+change
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+```cs
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+public CameraComponent Camera { get; set; }
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+```
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+to
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+```cs
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+public Entity Camera { get; set; }
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+```
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+
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+---
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+
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+### Utils.cs
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+change
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+```cs
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+CameraComponent camera
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+```
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+to
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+```cs
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+Entity camera,
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+```
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+and change
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+```cs
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+camera.Update();
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+var inverseView = Matrix.Invert(camera.ViewMatrix);
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+```
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+to
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+`var inverseView = camera.Transform.WorldMatrix;`
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+
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+---
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+
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+### FpsCamera.cs
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+Remove
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+```cs
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+
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+ /// <summary>
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+ /// Gets the camera component used to visualized the scene.
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+ /// </summary>
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+ private Entity Component;
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+```
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+and change
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+```cs
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+ private void UpdateViewMatrix()
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+ {
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+ var camera = Component;
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+ if (camera == null) return;
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+ var rotation = Quaternion.RotationYawPitchRoll(Yaw, Pitch, 0);
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+
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+ Entity.Transform.Rotation = rotation;
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+ }
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+```
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+to
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+```cs
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+private void UpdateViewMatrix()
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+{
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+ var rotation = Quaternion.RotationYawPitchRoll(Yaw, Pitch, 0);
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+
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+ Entity.Transform.Rotation = rotation;
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+}
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+```
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+
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+That should be all thats needed to see the smoothing in action as a before and after. You can see the original issue in the Stride Github [here](https://github.com/stride3d/stride/issues/2216) if you need to find more info on the problem.
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Vaclav Elias