unity射线检测高速飞行的子弹是否打到敌人

利用射线检测，检测两帧子弹位置连线是否碰撞敌人，并改变敌人状态。

控制敌人射出的子弹的类如下：

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

public class SoliderAmmoController : MonoBehaviour
{
    public float velocity = 50f;
    public float dis;
    public Vector3 posRecord;
    public Ray ray;
    public RaycastHit hit;
    public int damage = 10;
    float flyTime = 0f;
    Vector3 gravity;

    // Start is called before the first frame update
    void Start()
    {
        Destroy(gameObject, 2.5f);
        gravity = new Vector3(0f, 4.9f, 0f);
    }

    // Update is called once per frame
    void Update()
    {
        ammoMovement();
    }
    void ammoMovement()
    {
        flyTime += Time.deltaTime;
        posRecord = transform.position;
        transform.position += (transform.forward * velocity * Time.deltaTime-0*gravity*flyTime*flyTime);
        dis = (posRecord - transform.position).magnitude;
        if (dis > 0)
        {
            if (Physics.Raycast(posRecord, transform.forward, out hit,dis))
            {
                if (hit.transform.tag == "Player")
                {
                    hit.transform.GetComponent().currentHealth -= 10;
                    hit.transform.GetComponent().clip = hit.transform.GetComponent().metalShooted;
                    hit.transform.GetComponent().Play();
                }
                Destroy(gameObject);
            }
        }
    }
}

代码说明：

首先要声明射线类Ray和射线击中返回信息类RaycastHit的实例

    public Ray ray;
    public RaycastHit hit;

之后调用射线检测的函数，其中Physics.Raycast的输入数据类型为Physics.Raycast(Vector3，Vector3,RaycastHit,float)，第一个是发射点，第二个是射线方向，第三个是碰撞物信息，第四个是射线长度，输出为bool型。

下面是检查玩家子弹是否打中敌人的程序逻辑，分为打中身体和爆头两种情况。

            if (Physics.Raycast(posRecord, transform.forward, out hit, dis))
            {
                if (hit.transform.tag == "SoliderBody")
                {
                    Transform solider = hit.transform.parent;
                    solider.GetComponent().currentBlood -= 10;
                    solider.GetComponent().nowState = 4;
                    solider.GetComponent().SetInteger("soliderState", 4);
                    solider.GetComponent().SetInteger("damageState", (int)Random.Range(1f, 3.99f));
                    solider.GetComponent().waitTime = 0.667f;
                    solider.GetComponent().nevrousTime = 10f;
                    solider.GetComponent().clip = solider.GetComponent().bodyShooted;
                    solider.GetComponent().Play();
                }
                if (hit.transform.tag == "SoliderHead")
                {
                    Transform solider = hit.transform.parent;
                    solider.GetComponent().clip = solider.GetComponent().headShooted;
                    solider.GetComponent().Play();
                    solider.GetComponent().currentBlood -= 110;
                }
                Destroy(gameObject);
            }