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


//上帝视角摄像机

public class GodCamera : MonoBehaviour
{
    
    //相机
    Camera godCamera;
    //初始位置
    public Vector3 startPosition = new Vector3(0f, 0f, 0f);
    //最大x
    public float maxPosX = 100f;
    //最小x
    public float minPosX = -100f;
    //最大y
    public float maxPosY = 50f;
    //最小y
    public float minPosY = 10f;
    //最大z
    public float maxPosZ = 100f;
    //最小z
    public float minPosZ = -100f;
    
   
    //速度
    public float speed = 20;




    //bool isGameStart = true;
    // Start is called before the first frame update
    void Start()
    {
        godCamera = transform.GetComponent<Camera>();
        transform.position = startPosition;
        godCamera.fieldOfView = 60;
    }

    // Update is called once per frame
    void Update()
    {
        
       //移动
        Move();
        //视野缩放
        ScaleView();       

    }
    private void Move()
    {
        //当鼠标左键按下的时候,0表示鼠标左键
        if (Input.GetMouseButton(0))
        {
            var x = Input.GetAxis("Mouse X");//鼠标在两帧之间的水平偏移量
            var y = Input.GetAxis("Mouse Y");//竖直的偏移量
            if (x != 0 || y != 0)
            {
                Vector3 target = this.transform.position + new Vector3(x, 0, y) * speed;
                if (target.x > maxPosX || target.x < minPosX || target.z > maxPosZ || target.z < minPosZ)
                {
                    // 如果超出范围，则不更新位置  
                    return;
                }
                this.transform.position = Vector3.Lerp(this.transform.position, target, speed * Time.deltaTime);

            }
        }
    }

    private void ScaleView()
    {
        //获取到鼠标滚轮的值
        float mouseScrollWheel = Input.GetAxis("Mouse ScrollWheel");
        if (mouseScrollWheel != 0)
        {
            godCamera.fieldOfView += mouseScrollWheel * speed;
            if (godCamera.fieldOfView <= 38)
            {
                godCamera.fieldOfView = 38;
            }
            else if (godCamera.fieldOfView >= 95)
            {
                godCamera.fieldOfView = 95;
            }

        }
    }
}