如何让预制体Trash保持递增速度？重复生成时速度不重置

在Unity中重复生成名为“Trash”的对象时，期望它的速度能够持续递增，但每次生成新的Trash时，其速度都会回到初始值。如何实现让所有Trash对象始终使用持续递增的速度？

原Trash脚本代码 #

public class TrashScript : MonoBehaviour
{   
    float trashAcceleration = 2;
    float trashDespawn = -15;
    float trashInitialSpeed = 5;
    float trashProgressiveSpeed = 0;

    // Start is called before the first frame update
    void Start()
    {

    }

    // Update is called once per frame
    void Update()
    {
        trashInitialSpeed += trashAcceleration * Time.deltaTime;
        trashProgressiveSpeed = trashInitialSpeed * Time.deltaTime;

        transform.position += (Vector3.left * trashProgressiveSpeed);

        if (transform.position.x < trashDespawn)
        {
            Destroy(gameObject);
        }
    }
}

原生成Trash的Spawner代码 #

public class TrashSpawner : MonoBehaviour
{
    public GameObject trash;

    public float heightOffset;
    public float spawnRate;

    private float timer = 0;

    // Update is called once per frame
    void Update()
    {
        if(timer < spawnRate)
        {
            timer += Time.deltaTime;
        }
        else
        {
            SpawnTrash();
            timer = 0;
        }
    }

    void SpawnTrash()
    {
        float lowestPoint = transform.position.y - heightOffset;
        float highestPoint = transform.position.y + heightOffset;
        Instantiate(trash, new Vector3(transform.position.x, Random.Range(lowestPoint, highestPoint), 0), transform.rotation);
    }
}

问题原因 #

每个Trash实例都拥有独立的trashInitialSpeed变量，每次生成新Trash时，该变量会被重新初始化为5，导致新对象速度回到初始值，无法继承全局递增后的速度。

解决方案 #

将速度的全局状态统一放到TrashSpawner中管理，让所有Trash实例共享这个递增的速度值。以下提供两种实现逻辑：

逻辑1：所有Trash速度完全同步（全局统一递增） #

让Trash直接读取Spawner中的全局速度，确保所有对象速度完全一致。

修改后的TrashSpawner脚本

public class TrashSpawner : MonoBehaviour
{
    public static TrashSpawner Instance;
    public GameObject trash;

    public float heightOffset;
    public float spawnRate;
    public float globalTrashSpeed = 5f;
    public float trashAcceleration = 2f;

    private float timer = 0;

    void Awake()
    {
        Instance = this;
    }

    void Update()
    {
        // 持续递增全局速度
        globalTrashSpeed += trashAcceleration * Time.deltaTime;
        
        if(timer < spawnRate)
        {
            timer += Time.deltaTime;
        }
        else
        {
            SpawnTrash();
            timer = 0;
        }
    }

    void SpawnTrash()
    {
        float lowestPoint = transform.position.y - heightOffset;
        float highestPoint = transform.position.y + heightOffset;
        Instantiate(trash, new Vector3(transform.position.x, Random.Range(lowestPoint, highestPoint), 0), transform.rotation);
    }
}

修改后的TrashScript脚本

public class TrashScript : MonoBehaviour
{   
    float trashDespawn = -15;

    void Update()
    {
        // 直接使用Spawner中的全局速度
        float trashProgressiveSpeed = TrashSpawner.Instance.globalTrashSpeed * Time.deltaTime;
        transform.position += (Vector3.left * trashProgressiveSpeed);

        if (transform.position.x < trashDespawn)
        {
            Destroy(gameObject);
        }
    }
}

逻辑2：Trash继承当前全局速度后自行加速 #

每个Trash生成时继承当前全局速度，之后保持自身的加速度递增。

修改后的TrashSpawner脚本

public class TrashSpawner : MonoBehaviour
{
    public GameObject trash;

    public float heightOffset;
    public float spawnRate;
    public float globalTrashSpeed = 5f;
    public float trashAcceleration = 2f;

    private float timer = 0;

    void Update()
    {
        // 持续递增全局速度
        globalTrashSpeed += trashAcceleration * Time.deltaTime;
        
        if(timer < spawnRate)
        {
            timer += Time.deltaTime;
        }
        else
        {
            SpawnTrash();
            timer = 0;
        }
    }

    void SpawnTrash()
    {
        float lowestPoint = transform.position.y - heightOffset;
        float highestPoint = transform.position.y + heightOffset;
        GameObject newTrash = Instantiate(trash, new Vector3(transform.position.x, Random.Range(lowestPoint, highestPoint), 0), transform.rotation);
        
        // 将当前全局速度和加速度传递给新Trash
        TrashScript trashScript = newTrash.GetComponent<TrashScript>();
        if(trashScript != null)
        {
            trashScript.Initialize(globalTrashSpeed, trashAcceleration);
        }
    }
}

修改后的TrashScript脚本

public class TrashScript : MonoBehaviour
{   
    float trashDespawn = -15;
    float currentSpeed;
    float trashAcceleration;

    public void Initialize(float initialSpeed, float acceleration)
    {
        currentSpeed = initialSpeed;
        trashAcceleration = acceleration;
    }

    void Update()
    {
        // 自身继续加速
        currentSpeed += trashAcceleration * Time.deltaTime;
        float trashProgressiveSpeed = currentSpeed * Time.deltaTime;

        transform.position += (Vector3.left * trashProgressiveSpeed);

        if (transform.position.x < trashDespawn)
        {
            Destroy(gameObject);
        }
    }
}

内容的提问来源于stack exchange，提问作者Gonko