quantum-space-buddies/QSB/Animation/PlayerHeadRotationSync.cs

using UnityEngine;

namespace QSB.Animation
{
	public class PlayerHeadRotationSync : MonoBehaviour
	{
		private Animator _attachedAnimator;
		private Transform _lookBase;

		public void Init(Transform lookBase)
		{
			_attachedAnimator = GetComponent<Animator>();
			_lookBase = lookBase;
		}

		private void LateUpdate()
		{
			var bone = _attachedAnimator.GetBoneTransform(HumanBodyBones.Head);
			// Get the camera's local rotation with respect to the player body
			var lookLocalRotation = Quaternion.Inverse(_attachedAnimator.transform.rotation) * _lookBase.rotation;
			bone.localRotation = Quaternion.Euler(0f, 0f, lookLocalRotation.eulerAngles.x);
		}
	}
}