[SpaceShooter] 오브젝트 풀링 연습

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

public class ParticlePoolManager : MonoBehaviour
{
    public static ParticlePoolManager instance;

    private List<GameObject> particlePool = new List<GameObject>();
    [SerializeField]
    private int maxParticles = 10;
    [SerializeField]
    private GameObject particlePrefab;

    private void Awake()
    {
        instance = this;
        DontDestroyOnLoad(this.gameObject);
    }

    void Start()
    {
        for (int i = 0; i < this.maxParticles; i++)
        {
            GameObject particleGo = Instantiate(this.particlePrefab);
            particleGo.SetActive(false);
            particleGo.transform.SetParent(this.transform);
            particlePool.Add(particleGo);
        }
    }

    public GameObject GetParticle()
    {
        foreach (GameObject particleGo in particlePool)
        {
            if (!particleGo.activeSelf)
            {
                particleGo.transform.SetParent(null);
                return particleGo;
            }
        }
        return null;
    }

    public void ReleaseParticle(GameObject particleGo, float delay)
    {
        StartCoroutine(ReleaseAfterDelay(particleGo, delay));
    }

    private IEnumerator ReleaseAfterDelay(GameObject particleGo, float delay)
    {
        yield return new WaitForSeconds(delay);
        particleGo.SetActive(false);
        particleGo.transform.SetParent(this.transform);
    }
}

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

public class TestBulletPoolManager : MonoBehaviour
{
    public static TestBulletPoolManager instance;

    private List<GameObject> pool = new List<GameObject>();
    [SerializeField]
    private int maxBullets = 10;
    [SerializeField]
    private GameObject testBulletPrefab;

    private void Awake()
    {
        instance = this;
        DontDestroyOnLoad(this.gameObject);
    }

    void Start()
    {
        for (int i = 0; i < this.maxBullets; i++)
        {
            GameObject bulletGo = Instantiate(this.testBulletPrefab);
            bulletGo.SetActive(false);
            bulletGo.transform.SetParent(this.transform);
            this.pool.Add(bulletGo);
        }
    }

    public GameObject GetBullet()
    {
        foreach (GameObject bulletGo in this.pool)
        {
            if (bulletGo.activeSelf == false)
            {
                bulletGo.transform.SetParent(null);
                return bulletGo;
            }
        }
        return null;
    }

    //풀에 반환 
    public void Release(GameObject bulletGo)
    {
        bulletGo.SetActive(false);
        bulletGo.transform.SetParent(this.transform);
    }


}

using UnityEngine;
using UnityEngine.UI;

public class TestObjectPoolingMain : MonoBehaviour
{
    [SerializeField]
    private Button btn;

    [SerializeField]
    private TestBulletPoolManager bulletPool;

    private Vector3 shootDirection = Vector3.forward;

    private void Start()
    {
        this.btn.onClick.AddListener(() => {

            GameObject bulletGo = bulletPool.GetBullet();

            if (bulletGo != null)
            {
                bulletGo.transform.position = Vector3.zero;
                bulletGo.transform.rotation = Quaternion.LookRotation(shootDirection);  // 총알의 회전을 발사 방향으로 설정

                TestBullet1 bulletScript = bulletGo.GetComponent<TestBullet1>();
                bulletScript.SetDirection(shootDirection);

                bulletGo.SetActive(true);
            }

            // Rotate the shoot direction by 90 degrees around the y axis.
            shootDirection = Quaternion.Euler(0, 90, 0) * shootDirection;
        });
    }
}

using UnityEngine;

public class TestBullet1 : MonoBehaviour
{
    [SerializeField]
    private float speed = 1f;
    private Vector3 direction;

    public void SetDirection(Vector3 dir)
    {
        direction = dir;
        

    }

    void Update()
    {
        this.transform.Translate(direction * this.speed * Time.deltaTime, Space.World);
    }


    private void OnCollisionEnter(Collision collision)
    {
        if (collision.collider.CompareTag("Wall"))
        {
            Debug.Log("Bullet Hit Wall");

            // 파티클 생성 및 활성화
            GameObject particleGo = ParticlePoolManager.instance.GetParticle();
            if (particleGo != null)
            {

                ContactPoint cp = collision.GetContact(0); //충돌 지점의 정보 추출
                Quaternion rot = Quaternion.LookRotation(-cp.normal); //충돌한 총알의 법선 벡터를 쿼터니언 타입으로 변환

                particleGo.transform.rotation = rot;
                particleGo.transform.position = cp.point;


                particleGo.transform.SetParent(ParticlePoolManager.instance.transform);

                particleGo.SetActive(true);
                ParticlePoolManager.instance.ReleaseParticle(particleGo, 1f);
                particleGo.transform.position = collision.contacts[0].point;
                particleGo.SetActive(true);
                ParticlePoolManager.instance.ReleaseParticle(particleGo, 3f);  // 3초 후에 파티클 반환

            }

            TestBulletPoolManager.instance.Release(this.gameObject);
        }
    }

}