实现类似红警的框选

在这里插入代码片
```using System;
using System.Collections.Generic;
using Cinemachine;
using DefaultNamespace.UI;
using DefaultNamespace.UserData;
using UnityEngine;

namespace DefaultNamespace
{
   
   
    //做父类分脚本
    //做接口分功能
    public class GameManage : MonoBehaviour
    {
   
   
        public CinemachineVirtualCamera _cvm;
        private Queue<GameObject> _objs = new Queue<GameObject>();
        private Camera _camera;
        private Dictionary<GameObject, Player> _dicselect = new Dictionary<GameObject, Player>();
        bool edgeScrolling = false;
        private bool isCreat = false;

        public float edgeSize; //会产生移动效果的边缘宽度
        public float moveAmount; //移动速度
        private Vector3 camFollowPos; //用于给摄像机赋值
        public CinemachineVirtualCamera _look;

        private void Awake()
        {
   
   
            DataManage._ins.Init();
            MessageManage._ins.AddListenData<GameObject>(MyData.selectObj, SelectObj);
            MessageManage._ins.AddListenData(MyData.CreatAr, CreatStart);
            MessageManage._ins.AddListenData(MyData.OverCreatAr, CreatOver);
            _camera = Camera.main;
            _cvm.gameObject.SetActive(false);
            camFollowPos = _look.transform.position;
        }
        
        ///选中物体
        private