RotationCancel.cs

using UnityEngine;

namespace Chigusa
{
    /// <summary>
    /// 回転を打ち消す
    /// （スプライトなどで常に正面を向かせるなど）
    /// </summary>
    [ExecuteInEditMode]
    [DisallowMultipleComponent]
    public class RotationCancel : MonoBehaviour
    {
        [Tooltip("Edit中にも反映させる")]
        public bool executeInEditMode = true;



        /// <summary>
        /// Update
        /// </summary>
        void Update()
        {
#if UNITY_EDITOR
            if (!executeInEditMode)
                return;
#endif

            //  打ち消す
            if (transform.parent)
                transform.localRotation = Quaternion.Inverse(transform.parent.rotation);
            else
                transform.localRotation = Quaternion.identity;
        }

    }

}