Quaternion.LookRotation 注视旋转

Creates a rotation that looks along forward with the the head upwards along upwards

创建一个旋转，沿着forward（z轴）并且头部沿着upwards（y轴）的约束注视。也就是建立一个旋转，使z轴朝向view ?y轴朝向up。

Logs an error if the forward direction is zero.

如果forward方向是0，记录一个错误。

using UnityEngine;using System.Collections;public class example : MonoBehaviour {public Transform target;void Update() {Vector3 relativePos = target.position - transform.position;Quaternion rotation = Quaternion.LookRotation(relativePos);transform.rotation = rotation;}}