station_obscurum_unity/Assets/Scripts/UI/WaypointMarker.cs

using TMPro;
using UnityEngine;
using UnityEngine.UI;

public class WaypointMarker : MonoBehaviour
{
    public Image pointer;
    public Transform target;
    public TMP_Text distanceMarker;

    private Vector2 offset;

    // Start is called before the first frame update
    private void Start()
    {
        offset = distanceMarker.transform.position - pointer.transform.position;
    }

    // Update is called once per frame
    private void Update()
    {
        var minX = pointer.GetPixelAdjustedRect().width / 2;
        var maxX = Screen.width - minX;
        var minY = pointer.GetPixelAdjustedRect().height / 2;
        var maxY = Screen.height - minY;

        Vector2 pos = Camera.main.WorldToScreenPoint(target.position);

        if (Vector3.Dot(target.position - Camera.main.transform.position, Camera.main.transform.forward) < 0)
        {
            //target is behind player
            if (pos.x < Screen.width / 2)
                pos.x = maxX;
            else
                pos.x = minX;
        }

        pos.x = Mathf.Clamp(pos.x, minX, maxX);
        pos.y = Mathf.Clamp(pos.y, minY, maxY);

        pointer.transform.position = pos;
        distanceMarker.text =
            Mathf.RoundToInt(Vector3.Distance(Camera.main.transform.position, target.transform.position)) + " meters";
        if (pos.x < Screen.width / 2)
            distanceMarker.transform.position = pos + offset;
        else
            distanceMarker.transform.position = pos - offset;
    }
}