Raycast仅会返回false，即使预期为true

Question

我有以下FollowingNPC游戏对象，如果有直接视野，应该遵循Player对象：

这里Player对象：

BlockingLayer和Player层之间启用了物理碰撞：

FollowingNPC附带有以下脚本，该脚本始终返回“未命中”结果：Raycast始终为false。这不是预期的输出，因为两个对象之间似乎都具有清晰的视图，并且可以毫无问题地绘制调试射线。

public class FollowingNPC : MonoBehaviour
{
    private Vector3 heading, direction;
    private float distance;

    void Update()
    {
        heading = GameObject.FindGameObjectWithTag("Player").transform.position - transform.position;
        distance = heading.magnitude;
        direction = heading / distance;

        RaycastHit hit;
        if (Physics.Raycast(transform.position, direction, out hit))
        {
            if (hit.transform== GameObject.FindGameObjectWithTag("Player").transform)
            {
                Debug.DrawRay(transform.position, direction * distance, Color.red);
                Debug.Log("Hit Player");
            }
            else
            {
                Debug.DrawRay(transform.position, direction * distance, Color.yellow);
                Debug.Log("Hit Wall");
            }

        }
        else
        {
            Debug.DrawRay(transform.position, direction * distance, Color.white);
            Debug.Log("Not Hit");
        }
    }
}

Answer 1

请注意，在Unity中Physics和Physics2D是完全独立且分离的Physics引擎！

您有Rigidbody2D和Collider2D，所以您宁愿使用Physics2D.Raycast！

您还应强烈避免在Physics2D.Raycast中使用FindGameObjectWithTag，甚至多次使用，因为它非常昂贵！宁愿once并存储结果。

Update

稍后您也应该删除所有这些

// If possible and best would be to already reference it via the Inspector
[SerilaizeField] private Transform player;

// As fallback get it ONCE on runtime
private void Awake()
{
    if(!player) player = GameObject.FindGameObjectWithTag("Player").transform;
}

void Update()
{
    // actually those wouldn't really need to be fields
    heading = player.position - transform.position;
    distance = heading.magnitude;
    // This line isn't really necessary
    // If something I would use 
    //direction = heading.normalized
    direction = heading / distance;

    if (Physics2D.Raycast(transform.position, direction, out var hit))
    {
        if (hit.transform == player)
        {
            Debug.DrawRay(transform.position, direction * distance, Color.red);
            Debug.Log("Hit Player");
        }
        else
        {
            Debug.DrawRay(transform.position, direction * distance, Color.yellow);
            Debug.Log("Hit Wall");
        }
    }
    else
    {
        Debug.DrawRay(transform.position, direction * distance, Color.white);
        Debug.Log("Not Hit");
    }
}

，因为在Debug.Log中完成时它们也很昂贵！