unity中实现3d物体随着鼠标移动（xy平面上移动）

将MoveWithMouse代码挂载到脚本上，就可以实现物体的移动

using System.Collections;
using QFramework;
using UnityEngine;

public class MoveWithMouse : MonoBehaviour
{
    public bool beSleceted = false;
    private Vector3 dragOffset; // 拖拽偏移量
    public float dragSpeed = 2f;
    public float zOffset = 10f; // 物体与相机的深度偏移
    // Start is called once before the first execution of Update after the MonoBehaviour is created
    void Start()
    {
    }

    // Update is called once per frame
    void Update()
    {
        //text();
        HandleObjectInteraction();
    }
    

    /// <summary>
    /// 处理鼠标点中
    /// </summary>
    private void HandleObjectInteraction()
    {
        // 鼠标按下瞬间
        if (Input.GetMouseButtonDown(0))
        {
            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            RaycastHit hit;

            if (Physics.Raycast(ray, out hit))
            {
                Debug.Log($"被点的物体为:{hit.collider.gameObject.name}");
                if (hit.collider.transform.parent)
                {
                    Debug.Log($"被点物体的父物体为:{hit.collider.transform.parent.name}");
                }
                // 如果点中的是自己
                if (hit.collider.transform == this.transform)
                {
                    Debug.Log("武器被选中了");
                    // 选中并准备拖拽
                    beSleceted = true;
                    UpdateDragOffset();
                }
            }
        }else if(Input.GetMouseButtonUp(0)&&beSleceted == true)
        {
            beSleceted = false;
        }

        // 持续拖拽状态
        if (beSleceted == true && Input.GetMouseButton(0))
        {
            // 动态更新偏移量（处理物体移动中的位置变化）
            UpdateDragOffset();

            // 执行拖拽移动
            DragSelectedObject();

        }
    }

    // 动态计算偏移量（每次拖拽都更新）
    private void UpdateDragOffset()
    {
        if (!beSleceted) return;

        // 获取当前鼠标位置（深度使用物体当前位置的Z）
        Vector3 mouseWorldPos = GetMouseWorldPositionForObject(this.gameObject);

        // 计算当前偏移量
        dragOffset = mouseWorldPos-this.gameObject.transform.position;
    }

    // 带深度校正的鼠标位置获取
    private Vector3 GetMouseWorldPositionForObject(GameObject obj)
    {
        Vector3 screenPos = Camera.main.WorldToScreenPoint(obj.transform.position);
        Vector3 mousePos = Input.mousePosition;
        mousePos.z = screenPos.z; // 保持相同的Z深度

        return Camera.main.ScreenToWorldPoint(mousePos);
    }

    // 拖拽移动逻辑
    private void DragSelectedObject()
    {
        if (beSleceted)
        {
            Vector3 targetPosition = this.transform.position + dragOffset;

            // 直接移动
            this.gameObject.transform.position = Vector3.Lerp(
                this.gameObject.transform.position,
                targetPosition,
                Time.deltaTime * dragSpeed
            );
        }
        
    }
}