Csharp OverlapBox 几乎每次都返回 null

在回答之前，我想说，这样的产卵算法是非常危险的，因为你可以进入一个无限循环，当没有新的正方形的地方.至少，要使此代码更安全，您可以添加一个重试计数，以查找要生成的位置.但我会把它留给你的良知.

要使此算法工作，您应该了解，在单位的所有物理更新固定更新.所以，你对Phisycs或Phisics2D所做的所有操作，都是在处理对象的状态，这是在上一次物理更新中执行的.当你改变物体的位置时，物理核心不会立即捕捉到这种变化.作为一种解决办法，您可以在修复的更新中分别生成每个对象.就像这样:

public class Spawner : MonoBehaviour
{

    [SerializeField] private GameObject[] _squaresToSpawn;
    [SerializeField] private GameObject _quad;
    
    // Start is called before the first frame update
    void Start()
    {
        StartCoroutine(Spawn());
    }

    private IEnumerator Spawn()
    {
        var quadBoundaries = _quad.GetComponent<MeshCollider>().bounds;
        var squareRadius = new Vector2(1, 1);
        Vector2 spawnPoint;
        
        foreach (var square in _squaresToSpawn)
        {
            yield return new WaitForFixedUpdate();
            var isOverlapping = true;
            var retriesCount = 10;
            while (isOverlapping && retriesCount > 0)
            {
                
                spawnPoint = new Vector2(Random.Range(quadBoundaries.min.x + 1.5f, quadBoundaries.max.x - 1.5f), 
                    Random.Range(quadBoundaries.min.y + 1.5f, quadBoundaries.max.y - 1.5f));

                var hit = Physics2D.OverlapBox(spawnPoint, squareRadius,
                    0, LayerMask.GetMask("Square"));
                
                if (hit is null)
                {
                    square.transform.position = spawnPoint;
                    isOverlapping = false;
                }
                else
                {
                    retriesCount--;
                    if (retriesCount == 0)
                    {
                        Debug.LogError("Can't find place to spawn the object!!");
                    }
                }
            }
        }  
    }
}

But such code will have effect of continious spawning:

使对象在一个帧内正常繁殖.您应该手动将所有繁殖的对象边界框存储在代码中，并手动判断新的繁殖边界框是否与先前繁殖的对象发生冲突.