How to destroy instantiated prefabs in order in Unity using C#?-CodePudding

I am new to Unity as I am new to C#. I'm making a 2D endless runner, but I ran into some problems when I try to destroy the instantiated prefabs(level parts). I tried a few ways that I found online, but these methods destroyed the prefab that was instantiated latest(for example if I instantiated 10 level parts, only the 10th was destroyed). I'm looking for something that destroys the earliest instantiated prefabs. Thanks for your help! Have a good one :)

The code I have:

public class LevelGenerator : MonoBehaviour{

    private const float distance_to_spawn  = 100f;

    [SerializeField]private List<Transform> LevelPartList;

    [SerializeField]private Transform LevelPart0;

    [SerializeField]private GameObject player; 

    private Vector3 lastEndingBlock; 

    private Vector3 distance = new Vector3(5,3,0);

    private Transform lastLevelPartTransform;

    // the starting point of the spawning process
    private void Awake()
    {
        lastEndingBlock = LevelPart0.Find("ending_block").position;
    }
 
    // calling the spawning function, so it's infinite
    private void Update()
    {
        if(Vector3.Distance(player.transform.position,lastEndingBlock) < distance_to_spawn)
        {
            SpawnLevelPart();
        }
    }
    
    // choose randomly out of the prefabs(level parts)
    private void SpawnLevelPart()
    {
        Transform chosenLevelPart = LevelPartList[Random.Range(0,LevelPartList.Count)];
        lastLevelPartTransform= SpawnLevelPart(chosenLevelPart,lastEndingBlock - distance);
        lastEndingBlock = lastLevelPartTransform.Find("ending_block").position;
    }

    // the function used to spawn new level parts
    private Transform SpawnLevelPart(Transform LevelPart,Vector3 spawnPosition)
    {
        Transform levelPartTransform = Instantiate(LevelPart,spawnPosition,Quaternion.identity);
        return levelPartTransform;
    }
}

CodePudding user response：

Intead of keeping the spare private Transform lastLevelPartTransform; I would keep the, in a Queue like so:

private Queue<Transform> transformsToDestroy = new Queue<Transform>();

// choose randomly out of the prefabs(level parts)
private void SpawnLevelPart()
{
    Transform chosenLevelPart = LevelPartList[Random.Range(0,LevelPartList.Count)];
    gosToDestroy.Enqueue(SpawnLevelPart(chosenLevelPart,lastEndingBlock - distance));
    lastEndingBlock = lastLevelPartTransform.Find("ending_block").position;
}

So that wherever you need, you can Destroy(transformsToDestroy.Dequeue().gameObject)

CodePudding user response：

Hello Gergő Starosta! If you want to delete objects that you instantiating before, you can basically collect all instantiated objects under one parent object.

private Transform SpawnLevelPart(Transform LevelPart,Vector3 spawnPosition)
    {
        Transform levelPartTransform = Instantiate(LevelPart,spawnPosition,Quaternion.identity);
        levelPartTransform.parent = parentObject.transform;
        return levelPartTransform;
    }

After that, you can use this:

Destroy(parentObject.GetChild[ChildNumber])