unity3d让三维物体跟随鼠标

效果图：

1.创建一个三维物体Cylinder圆柱体 Target

2.创建词汇表Yellow材质球

3.将材质球挂载到Target物体上

4.创建脚本MouseMove.cs

MouseMove.cs代码

using UnityEngine;
/*
 让物体完全跟随鼠标
     */
public class MouseMove : MonoBehaviour
{
    [Header("主相机")]
    [Tooltip("主相机")]
    /// 

    /// 主相机
    /// 
    public Camera m_mainCamera;
    [Header("目标物体")]
    [Tooltip("目标物体")]
    /// 

    /// 目标物体
    /// 
    public Transform m_target;

    void Start()
    {
        isDown = false;
        targetWTSP = m_mainCamera.WorldToScreenPoint(m_target.position);
    }
    /// 

    /// 是否按下
    /// 
    private bool isDown;
    /// 

    /// 记录初始化时候target世界坐标转屏幕坐标时候的位置 WTSP==WorldToScreenPoint
    /// 
    private Vector3 targetWTSP;
    void Update()
    {
        if (Input.GetMouseButtonDown(0)) {
            isDown = true;
        }
        if (Input.GetMouseButtonUp(0))
        {
            isDown = false;
        }
    }
    private void LateUpdate()
    {
        if (isDown)
        {
            Vector3 mouseVec3 = m_mainCamera.ScreenToWorldPoint(
                new Vector3(Input.mousePosition.x, Input.mousePosition.y, targetWTSP.z)
            );
            m_target.position = mouseVec3;
        }
    }
}

5.新建一个空物体Script，并将MouseMove.cs脚本挂载上去，再将相机和Target物体拖拽到脚本上

完毕！