Unity 相机平移、旋转、缩放

内容不多，一个脚本，直接上代码

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

public class Move : MonoBehaviour
{

    float speed = 20;
    public float distance_v;
    public float distance_h;
    public float rotation_H_speed = 1;
    public float rotation_V_speed = 1;
    public float max_up_angle = 80;              //越大，头抬得越高
    public float max_down_angle = -60;           //越小，头抬得越低


    private float current_rotation_H;  //水平旋转结果
    private float current_rotation_V;  //垂直旋转结果
    void LateUpdate()
    {
        // 旋转
        if (Input.GetMouseButton(1))
        {
            //控制旋转
            current_rotation_H += Input.GetAxis("Mouse X") * rotation_H_speed;
            current_rotation_V += Input.GetAxis("Mouse Y") * rotation_V_speed;
            //current_rotation_V = Mathf.Clamp(current_rotation_V, max_down_angle, max_up_angle);       //限制垂直旋转角度
            transform.localEulerAngles = new Vector3(-current_rotation_V, current_rotation_H, 0f);
            transform.Translate(Vector3.back * distance_h, Space.Self);
            transform.Translate(Vector3.up * distance_v, Space.World);          //相对于世界坐标y轴向上
        }

        // 平移
        if (Input.GetMouseButton(2))
        {
            this.transform.Translate(new Vector3(-Input.GetAxis("Mouse X") * rotation_H_speed, -Input.GetAxis("Mouse Y") * rotation_V_speed, 0f));
        }
    }
    // Use this for initialization
    void Start()
    {

    }

    // Update is called once per frame
    void Update()
    {
        // 移动
        if (Input.GetKey(KeyCode.A)) //左移
        {
            transform.Translate(Vector3.left * speed * Time.deltaTime);
        }
        if (Input.GetKey(KeyCode.D)) //右移
        {
            transform.Translate(Vector3.right * speed * Time.deltaTime);

        }
        if (Input.GetKey(KeyCode.W)) //前移
        {
            transform.Translate(Vector3.forward * speed * Time.deltaTime);

        }
        if (Input.GetKey(KeyCode.S)) //后移
        {
            transform.Translate(Vector3.back * speed * Time.deltaTime);

        }

        // 缩放
        if (Input.GetAxis("Mouse ScrollWheel") != 0)
        {
            //获取鼠标滚轮的滑动量
            float wheel = Input.GetAxis("Mouse ScrollWheel") * Time.deltaTime * 5000;

            //改变相机的位置
            this.transform.Translate(Vector3.forward * wheel);
        }
    }
}