使用Coroutines

Question

我正在尝试用棒球格式创建一个击球游戏。我创造了一个球作为预制件。我想在一段时间内把球推到主场面。

例如;当第一个球在场景中时，第二个球将在5-6秒后产生，然后是第三个，第四个等等。我是Unity的初级水平，我不擅长C＃。我不确定我是否正在使用Instantiate等真正的函数。这是我的剧本：

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

public class Ball : MonoBehaviour {
    public float RotateSpeed = 45; //The ball rotates around its own axis
    public float BallSpeed = 0.2f; 

    public GameObject[] prefab;

    public Rigidbody2D rb2D;

    void Start() {
        rb2D = GetComponent<Rigidbody2D>(); //Get component attached to gameobject
        Spawn ();
    }

    void FixedUpdate() {
        rb2D.MoveRotation(rb2D.rotation + RotateSpeed * Time.fixedDeltaTime); //The ball rotates around its own axis
        rb2D.AddForce(Vector2.left * BallSpeed);
        InvokeRepeating("Spawn", 2.0f, 2.0f);

    }

    public void Spawn () 
    {
        int prefab_num = Random.Range(0,3);
        Instantiate(prefab[prefab_num]);
    }

}

应用此脚本后，结果不是我想要的。

Answer 1

将InvokeRepeating("Spawn", 2.0f, 2.0f);添加到Start而不是FixedUpdate。 InvokeRepeating在时间秒内调用方法methodName，然后每隔repeatRate秒重复一次。您可以查看文档here。

Answer 2

使用Coroutines

private IEnumerator SpawnBall() {
    while(true) {
        Instantiate(baseball);
        yield return new WaitForSeconds(5);
    }
}

然后可以使用StartCoroutine()开始，然后以三种方式之一终止：

在内部打开break的while循环（该函数将不再有行执行和退出）
内部由yield break
在外部通过对协程

StopCoroutine()

Answer 3

替代其他答案：只需使用倒计时。这有时会给你更多的控制权

// Set your offset here (in seconds)
float timeoutDuration = 2;

float timeout = 2;

void Update()
{
    if(timeout > 0)
    {
        // Reduces the timeout by the time passed since the last frame
        timeout -= Time.deltaTime;

        // return to not execute any code after that
        return;
    }

    // this is reached when timeout gets <= 0

    // Spawn object once
    Spawn();

    // Reset timer
    timeout = timeoutDuration;
}

Answer 4

我通过考虑您的反馈来更新我的脚本，它就像一个魅力。谢谢大家！

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using System.Threading;

public class Ball : MonoBehaviour {
    public float RotateSpeed = 45; //The ball rotates around its own axis
    public float BallSpeed = 0.2f; 

    public GameObject BaseBall;
    public Transform BallLocation;

    public Rigidbody2D Ball2D;

    void Start() {
        Ball2D = GetComponent<Rigidbody2D>(); //Get component attached to gameobject
        InvokeRepeating("Spawn", 5.0f, 150f);
    }       

    void FixedUpdate() {
        Ball2D.MoveRotation(Ball2D.rotation + RotateSpeed * Time.fixedDeltaTime); //The ball rotates around its own axis
        Ball2D.AddForce(Vector2.left * BallSpeed);
    }

    public void Spawn () 
    {
        Instantiate (BaseBall, BallLocation.position, BallLocation.rotation);
    }
}

如何在Unity中的某段时间内生成预制件？

4 个答案:

使用Coroutines