DeltaVR3DModelGeneration/Assets/_PROJECT/Scripts/ModeGeneration/QuestMarker.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class QuestMarker : MonoBehaviour
{
    public Transform movingPart;
    public float amplitude = 0.1f;      // How far up/down it moves
    public float frequency = 1.5f;      // Speed of oscillation
    public float heightAboveTarget = 1f;

    private Vector3 startPos;
    private Transform playerTransform;

    // Start is called before the first frame update
    void Start()
    {
        startPos = movingPart.localPosition;
    }

    // Update is called once per frame
    void Update()
    {
        // Float up and down
        float offset = Mathf.Sin(Time.time * frequency) * amplitude;
        movingPart.localPosition = startPos + new Vector3(0f, offset, 0f);

        if (playerTransform != null)
        {
            // Turn towards player
            Vector3 lookTargetPos = new Vector3(playerTransform.position.x, transform.position.y, playerTransform.position.z);
            transform.LookAt(lookTargetPos);
        }
    }

    private void OnTriggerEnter(Collider other)
    {
        if (other.gameObject.tag == "Player Head")
        {
            playerTransform = other.transform;
        }
    }

    private void OnTriggerExit(Collider other)
    {
        if (other.gameObject.tag == "Player Head")
        {
            playerTransform = null;
        }
    }

    public void MoveTo(Transform target)
    {
        transform.position = target.position + new Vector3(0, heightAboveTarget, 0);
    }
}