unity 对象池，会自动扩容

Unity对象池

对象池，每次都会调用第一个没有被隐藏的对象。

using System.Collections.Generic;
using UnityEngine;

public class ObjectPool<T> where T : Component
{
    private Queue<T> objectQueue;//没有被使用的对象的队列
    private HashSet<T> activeObjects;//已经激活对象的队列
    private T prefab;//对象的预制体
    private int poolSize;//对象池的大小
    private int initialPoolSize;//对象池初始大小

//创建对象池，对象的预制体，对象池的初始大小
    public ObjectPool(T prefab, int poolSize)
    {
        this.prefab = prefab;
        this.poolSize = poolSize;
        this.initialPoolSize = poolSize;
        objectQueue = new Queue<T>();
        activeObjects = new HashSet<T>();

        for (int i = 0; i < poolSize; i++)
        {
            T obj = GameObject.Instantiate(prefab);
            obj.gameObject.SetActive(false);
            objectQueue.Enqueue(obj);
        }
    }

//获取对象池中的物体，默认是会获取第一个物体，
    public T GetObject()
    {
        if (objectQueue.Count == 0)
        {
            ExpandPool();
        }

        T obj = objectQueue.Dequeue();
        obj.gameObject.SetActive(true);
        activeObjects.Add(obj);
        return obj;
    }
//拓展池，当池内的物体不够用的时候会自行拓展
    private void ExpandPool()
    {
        int newSize = poolSize * 2;
        for (int i = poolSize; i < newSize; i++)
        {
            T obj = GameObject.Instantiate(prefab);
            obj.gameObject.SetActive(false);
            objectQueue.Enqueue(obj);
        }
        poolSize = newSize;
        Debug.Log($"Pool expanded to size: {poolSize}");
    }
//使用完毕后将对象返回到对象池中去
    public void ReturnObject(T obj)
    {
        obj.gameObject.SetActive(false);
        objectQueue.Enqueue(obj);
        activeObjects.Remove(obj);
    }

    /// <summary>
    /// 获取池中的全部active对象
    /// </summary>
    /// <returns></returns>
    public List<T> GetActiveObjects()
    {
        return new List<T>(activeObjects);
    }
}

用法：

using UnityEngine;

public class Bullet : MonoBehaviour
{
    // Bullet 类的具体实现
 publick BulletSpawner  bullpool;
 
private void Start(){
Invoke(nameof(SS),1.0f);
}

private void SS(){
bullpool. ReturnBullet(this);
}
}

public class BulletSpawner : MonoBehaviour
{
    public Bullet bulletPrefab;
    private ObjectPool<Bullet> bulletPool;

    void Start()
    {
    //设置对象池的大小
        bulletPool = new ObjectPool<Bullet>(bulletPrefab, 10);
    }

    void Update()
    {
        if (Input.GetKeyDown(KeyCode.Space))
        {
            Bullet bullet = bulletPool.GetObject();
            bullet.transform.position = transform.position;
            // 其他初始化逻辑
        }
    }

    public void ReturnBullet(Bullet bullet)
    {
        bulletPool.ReturnObject(bullet);
    }
}