[游戏开发]unity拖拽UI生成Cube并跟随鼠标移动，放置点可放下

代码：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Events;
using UnityEngine.EventSystems;
using UnityEngine.UI;

public class DragCreate : MonoBehaviour 
{
    public GameObject Cube;
    public GameObject Place;


    /// <summary>
    /// 按下响应
    /// </summary>
    public void PointerDown()
    {
        OnBeginDrag();
    }
    /// <summary>
    /// 开始拖拽
    /// </summary>
    public void OnBeginDrag()
    {
        GameObject game = Instantiate(Cube);
        game.SetActive(true);
        generateGame = game;

        float distance = Camera.main.transform.InverseTransformPoint(Place.transform.position).z;

        generateGame.transform.position = Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x,
            Input.mousePosition.y, distance));


        generateGame.transform.rotation = Place.transform.rotation;

        Place.SetActive(true);
    }

    private GameObject generateGame;
    /// <summary>
    /// 进行拖拽
    /// </summary>
    public void OnDrag()
    {
        float distance = Camera.main.transform.InverseTransformPoint(Place.transform.position).z;

        generateGame.transform.position = Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x,
            Input.mousePosition.y, distance));

    }

    /// <summary>
    /// 结束拖拽
    /// </summary>
    public void OnEndDrag()
    {
        if (generateGame.transform.position.x > Place.transform.position.x - 0.3f
            && generateGame.transform.position.x < Place.transform.position.x + 0.3f
            && generateGame.transform.position.y > Place.transform.position.y - 0.3f
            && generateGame.transform.position.y < Place.transform.position.y + 0.3f) 
        {
            Place.SetActive(false);
            generateGame.transform.position = Place.transform.position;
        }
        else
        {
            Place.SetActive(false);
            Destroy(generateGame);
        }
    }
}

脚本挂载和层级：

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