How can I create a instantiate my border around a “bronze” when it is the closest and destroy the border when no longer the closest?

Question

I\'ve been stuck at this for a while. What I want is for my outline object to be instantiated at the location of my bronze Base game object and for it to destroy when the bronze

Answer 1

In the Bronze in notSelected you are destroying the prefab selectBox!

You probably rather wanted to destroy the clone instance.

---

Anyway I would suggest a few things that I would do different

• Instead of Instantiate and Destroy all the time rather only use SetActive
• Instead of using FindObjectOfType in Update store them in a HashSet event driven: Each Bronze instance registers and unregisters itself
• Depends on personal taste but I would use Linq to find the closest instance

This could look somewhat like

public class Bronze : MonoBehaviour
{
    // Every instance of this component registers and unregisters itself here
    public static readonly HashSet<Bronze> Instances = new HashSet<Bronze>();

    [Header("References")]
    public Animator anim;
    [SerializeField] private GameObject selectedBox;
    [SerializeField] private GameObject bronzeBase;

    [Header("Debugging")]
    [SerializeField] bool _isSelected = false;

    private GameObject clone;

    // Have a property for the selection
    public bool IsSelected
    {
        // when something reads this property return _isSelected
        get => _isSelected;
        // This is executed everytime someone changes the value of IsSelected
        set
        {
            if(_isSelected == value) return;

            _isSelected = value;

            clone.SetActive(_isSelected);
        }
    }

    // Update is called once per frame
    void Awake()
    {
        // Instantiate already returns the type of the given prefab
        clone = Instantiate(selectedBox, bronzeBase.transform);

        // Register yourself to the alive instances
        Instances.Add(this);
    }

    private void OnDestroy ()
    {
        // Remove yourself from the Instances
        Instances.Remove(this);
    }
}

And then use it

using System.Linq;

public class FindBronze : MonoBehaviour
{
    private Bronze currentSelected;

    private void Update()
    {
        UpdateClosestBronze();
    }

    void UpdateClosestBronze()
    {
        if(Bronze.Instances.Count ==0) return;

        // This takes the instances
        // orders them by distance ascending using the sqrMagnitude
        // of the vector between the Instance and you
        // sqrMagnitude is more efficient than Vector3.Distance when you only need to compare instead of the actual distance
        // then finally it takes the first item 
        var newClosest = Bronze.Instances.OrderBy(b => (b.transform.position - transform.position).sqrMagnitude).First();

        // skip if the result is the same as last time
        if(newClosest == currentSelected) return;

        // otherwise first deselect the current selection if there is one
        if(currentSelected)
        {
            currentSelected.IsSelected = false;
        }
   
        // Then set the new selection     
        currentSelected = newSelected;
        currentSelected.IsSelected = true;
    }
}