Infrared, ray detection in Unity games

In games such as RPG games, when we click on the map, the character goes to the clicked location. This process can also be that we click on the screen, and a ray is emitted from the plane of the camera, pointing to the clicked location. 

For example: we click a certain place, the sphere will go to a certain place

Create a script to mount on the sphere 

Screenplay:

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

public class RayTest : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        //方式一
        //Ray ray = new Ray(Vector3.zero, Vector3.up);
        //方式二
        //通过摄像机获得射线，ScreenPointToRay 从屏幕点开始发射射线 Input.mousePosition 鼠标按到的点
        //Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
    }

    // Update is called once per frame
    void Update()
    {
        //按住鼠标左键发射射线
        if (Input.GetMouseButtonDown(0))
        {
            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            //声明一个碰撞信息类
            RaycastHit hit;
            //碰撞检测
            //Physics.Raycast物理类里面一个射线检测方法，out hit 注意out+空格是C#里面的语法，我们声明了信息类，而out会帮助我们填写内容
            bool res = Physics.Raycast(ray, out hit);
            //如果碰撞到的情况下，hit就有内容了，反之就没有内容了
            if (res)
            {
                Debug.Log(hit.point);
                transform.position = hit.point;
            }
            //多检测
            //100：检测距离， 1<<10：只检测第十个图层
            RaycastHit[] hit = Physics.RaycastAll(ray, 100, 1<<10);
        }
    }
}