[游戏开发]Unity + Mirror NetworkTransform 从客户端到服务器

开发多人同步项目时，物体Transform信息同步分为两种：

1. Player（客户端自主控制，服务器广播，其他客户端刷新）
2. NPC（自身带有AI逻辑，服务器广播其Transform、Animator属性，所有客户端刷新）
3. 可接力操作物体（如Aclient 将一个物体交给BClient）

前两种情况，网上教程很多，不再赘述。

第三种情况，没有找到相关介绍，而且官网介绍也有一个坑。

Network Transform - Mirrorhttps://mirror-networking.gitbook.io/docs/components/network-transform这里说到

By default, Network Transform is server-authoritative unless you check the box for Client Authority. Client Authority applies to player objects as well as non-player objects that have been specifically assigned to a client, but only for this component. With this enabled, position changes are send from the client to the server.

实践中：场景创建Cube添加NetworkTransform（自动添加NetworkIdentity）勾选ClientAuthority

?打包测试后发现，客户端和服务器都自能各自移动，却不同步位置。

解决方案：仍然勾选该选项，并且在当前操作client请求权限

注意Command请求只能在player上，所以该脚本应该放挂在player上

using Mirror;
using UnityEngine;

public class AuthorityAndOwnerShip : NetworkBehaviour
{
    private GameObject prefab;



    void Update() 
    {
        bool isplayerDead = false;

        if (isplayerDead && base.hasAuthority)
        {
            CmdRequestRespawn();
        }

        RequestOwnerShipOnClick();
    }

    [Command]
    private void CmdRequestRespawn() 
    {
        NetworkServer.Spawn(prefab,GetComponent<NetworkIdentity>().connectionToClient);
    }



    private void RequestOwnerShipOnClick() 
    {
        if (!base.hasAuthority)
        {
            return;
        }

        if (!Input.GetMouseButton(2))
        {
            return;
        }

        RaycastHit hit;
        if (Physics.Raycast(Camera.main.ScreenPointToRay(Input.mousePosition),out hit,100))
        {
            NetworkIdentity id = hit.collider.GetComponent<NetworkIdentity>();

            if (id != null && !id.hasAuthority)
            {
                CmdRequestAuthority(id);
            }
        }
    }


    [Command]
    private void CmdRequestAuthority(NetworkIdentity id)
    {
        id.RemoveClientAuthority();
        id.AssignClientAuthority(base.connectionToClient);
    }
}

为了验证该效果，在Cube 上挂载一个验证脚本

using Mirror;
using UnityEngine;

public class ChangeColorOnAuthority : NetworkBehaviour
{

    public override void OnStartAuthority()
    {
        base.OnStartAuthority();

        GetComponent<MeshRenderer>().material.color = Color.blue;
    }

    public override void OnStopAuthority()
    {
        base.OnStopAuthority();

        GetComponent<MeshRenderer>().material.color = Color.white;

    }

    void Update() 
    {
        if (Input.GetMouseButton(1))
        {
            transform.Rotate(Vector3.down, Input.GetAxis("Mouse X"));
            transform.Rotate(Vector3.left, -Input.GetAxis("Mouse Y"));
        }
    }
}

链接后，在client上用鼠标中键点击cube、接收到权限后会变成蓝色。此时点击鼠标右键并滑动。旋转角度就会同步回服务器了。

效果视频：