Question

统一的新事物。

所以我创建了一个简单的枪口闪光粒子动画，该动画应该在玩家靠近他时显示在敌人的枪上，模拟没有实际子弹的射击。但是我在这部分muzzleFlash.Play();中得到了一个空引用异常，我相信这是因为我实际上并没有使用我拥有的代码在start函数中获得枪口Flash组件，实际上我知道这是在调试之后的结果我发现的模式。我很难弄清楚如何访问该组件。下面是我的代码，我还发布了我的层次结构图。预先感谢。

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

public class StaticShootingEnemy : MonoBehaviour
{

    [SerializeField] private float _range = 12f;
    private Transform _player;

    private bool _alive;
    private float _distance;
    private ParticleSystem muzzleFlash;

    // Use this for initialization
    void Start()
    {
        _player = GameObject.Find("Player").transform;
        _alive = true;
        muzzleFlash = (ParticleSystem)this.gameObject.GetComponent("muzzleFLash");

    }

    // Update is called once per frame
    void Update()
    {
        _distance = Vector3.Distance(this.transform.position, _player.transform.position);
        if (_alive && _distance < _range)
            AttackPlayer();
    }


    private void AttackPlayer()
    {
        //Turning enemy to look at player
        transform.LookAt(_player);
        Ray ray = new Ray(transform.position, transform.forward);
        RaycastHit hit;
        if (Physics.SphereCast(ray, 0.75f, out hit))
        {
            //TODO: Fix enemy shooting fast when gettting close to him.
            GameObject hitObject = hit.transform.gameObject;
            if (hitObject.GetComponent<PlayerController>())
            {
                muzzleFlash.Play();
                Debug.Log("Player Hit!");
            }
            else
                muzzleFlash.Stop();
        }
    }

    public void SetAlive(bool alive)
    {
        _alive = alive;
    }

}

Answer 1

您可能将对象“ muzzleFlash”作为子对象来附加脚本。因此，在这种情况下，最好有一个对您的ParticleSystem对象的引用，称为muzzleFlash。

[SerializeField] private ParticleSystem muzzleFlash; // drag and drop your ParticleSystem muzzleFlash in inspector

或者至少您可以找到像这样的muzzleFlash

GameObject muzzleFlashObj = GameObject.Find("muzzleFlash"); ParticleSystem muzzleFlash = muzzleFlashObj.GetComponent<ParticleSystem>();

在您的情况下，它为null，因为该对象上可能没有称为MuzzleFlash的组件。您要获取的组件是ParticleSystem。

Answer 2

staticshootingenemy脚本位于哪个组件上？如果它与粒子系统不在同一个组件上，则找不到它，因为this.gameObject.GetComponent（“ muzzleFLash”）在该组件上不存在。您可以使用GameObject.Find（“ muzzleFLash”）搜索粒子系统。

Answer 3

因此，回到您的评论中，您可以为枪口闪烁实现类似池的功能。

public class MuzzleFlashEffect : MonoBehaviour
{
    [SerializeField] private ParticleSystem particleEffect;
    private Queue<MuzzleFlashEffect> poolQueue;

    public void SetPoolQueue(Queue<MuzzleFlashEffect> queue)
    {
        poolQueue = queue;
    }

    public void Play()
    {
        StartCoroutine(Playing());
    }

    private IEnumerator Playing()
    {
        particleEffect.Play();

        while (particleEffect.isPlaying)
        {
            yield return null; // wait until particle animation is done, then recycle effect
        }

        particleEffect.Stop();
        poolQueue.Enqueue(this);  // recycle this effect
    }

    // you can do the same thing for Animation as well, or even write some abstract PoolableVFX class that would be usefull for Animation , ParticleSystems etc.. 
}

//assume you have some game controller that manage what is going on in the scene
public class GameController : MonoBehaviour
{
    [SerializeField] private MuzzleFlashEffect muzzleFlashPrefab;
    private Queue<MuzzleFlashEffect> poolQueue = new Queue<MuzzleFlashEffect>(10); // 10 is enough i guess and it's good to set it at instantiation to avoid memory fragmentation

    private MuzzleFlashEffect GetMuzzleFlash(Vector3 pos, Quaternion rot)
    {
        MuzzleFlashEffect muzzleFlash;

        // if we already have some effects, then play them, otherwise make a new one and recycle it then
        if (poolQueue.Count > 0)
        {
            muzzleFlash = poolQueue.Dequeue();
        }
        else
        {
            muzzleFlash = Instantiate(muzzleFlashPrefab);
            muzzleFlash.SetPoolQueue(poolQueue);
        }

        muzzleFlash.transform.position = pos;
        muzzleFlash.transform.rotation = rot;

        return muzzleFlash;
    }

    void Update()
    {
        // your fancy logic ...


        GameObject mutantGunEnd = new GameObject("mutant");
        //assume that here you want your muzzle flash effect, so you do:

        var muzzleFlash = GetMuzzleFlash(mutantGunEnd.transform.position, mutantGunEnd.transform.rotation); // or you might want to pass mutantGunEnd.transform.forward instead, it depends... 
        muzzleFlash.Play();


        // your fancy logic ...
    }
}

因此，在这种情况下，您仅具有所需数量的ParticleEffect实例，并节省了一些资源。您也可以为要回收的任何类型的对象创建通用通用池。（您想回收而不是实例化，因为cuz实例化是cpu昂贵的）。 M.b，这在这里有点矫but过正，但我只是想分享一下我对此的看法

了解Unity的GameObject.Find（），GetComponent（）和对象回收

3 个答案: