mmorpg2d/Assets/Script/rangeEnemyFinder.cs

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

public class rangeEnemyFinder : MonoBehaviour
{
    public float radius = 10;
    public enemyScript[] enemies;

    public Transform lockIndicator;

    private void OnDrawGizmos() {
        Gizmos.DrawWireSphere(transform.position, radius);
    }

    void Start()
    {
        
    }

    // Update is called once per frame
    public enemyScript targetEnemy;
    
    void Update()
    {
        enemies = FindObjectsOfType<enemyScript>();
        float closestDist = radius * 10f;
        targetEnemy = null;
        foreach(enemyScript enemy in enemies){
            float dist = Vector3.Distance((Vector2)enemy.transform.position,(Vector2)transform.position);
            if(dist < radius){
                if(dist < closestDist){
                    targetEnemy = enemy;
                    closestDist = dist;
                }
            }
        }

        lockIndicator.gameObject.SetActive(targetEnemy!= null);

        if(targetEnemy != null){
            //show indicator 
            lockIndicator.position = targetEnemy.transform.position + new Vector3 (0, 0.62f, 0);
        }
    }
}