Unity3D 进阶教程 - 17 多人游戏架构实战

概述

上一篇掌握了 Netcode for GameObjects 的核心 API。这一篇从 系统架构 的角度出发，讨论一个完整的多人游戏项目应该怎么组织——房间管理、状态同步策略、网络性能优化、以及常见的坑。

1. 多人游戏架构分层

Presentation（表现层）  <- Prefabs、动画、特效（客户端本地执行）
Network（网络层）       <- RPC、NetworkVariable、消息序列化
Game Logic（逻辑层）    <- 状态机、游戏规则（服务器权威）
Data（数据层）          <- 玩家数据、房间状态、排行榜

---

2. 房间管理系统

2.1 房间数据结构

[System.Serializable]
public struct RoomData : INetworkSerializable
{
    public FixedString64Bytes RoomName;
    public FixedString64Bytes HostName;
    public int MaxPlayers;
    public int CurrentPlayers;
    public RoomState State;

    public void NetworkSerialize<T>(BufferSerializer<T> serializer) where T : IReaderWriter
    {
        serializer.SerializeValue(ref RoomName);
        serializer.SerializeValue(ref HostName);
        serializer.SerializeValue(ref MaxPlayers);
        serializer.SerializeValue(ref CurrentPlayers);
        serializer.SerializeValue(ref State);
    }
}

public enum RoomState : byte
{
    Waiting,
    Starting,
    Playing,
    Finished
}

2.2 房间管理器

public class RoomManager : NetworkBehaviour
{
    public static RoomManager Instance { get; private set; }
    private readonly Dictionary<ulong, RoomData> _rooms = new();
    public NetworkList<RoomData> RoomList => _roomList;
    private NetworkList<RoomData> _roomList;

    private void Awake()
    {
        Instance = this;
        _roomList = new NetworkList<RoomData>();
    }

    [ServerRpc(RequireOwnership = false)]
    public void CreateRoomServerRpc(FixedString64Bytes roomName,
        FixedString64Bytes playerName, ServerRpcParams rpcParams = default)
    {
        var senderId = rpcParams.Receive.SenderClientId;
        var room = new RoomData
        {
            RoomName = roomName,
            HostName = playerName,
            MaxPlayers = 4,
            CurrentPlayers = 1,
            State = RoomState.Waiting
        };
        _rooms[senderId] = room;
        _roomList.Add(room);
    }
}

---

3. 同步策略

3.1 完全同步（服务器权威）

public class FullySyncedPlayer : NetworkBehaviour
{
    private NetworkVariable<Vector3> Position = new();
    private NetworkVariable<float> Health = new();

    [ServerRpc]
    public void SubmitInputServerRpc(Vector2 moveInput, bool fire)
    {
        Move(moveInput);
        if (fire) Fire();
    }
}

优点：防止作弊。缺点：延迟感明显。

3.2 客户端预测

public class PredictedPlayer : NetworkBehaviour
{
    private Vector3 _localPosition;

    private void Update()
    {
        if (!IsOwner) return;

        var move = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
        _localPosition += move * Time.deltaTime * _speed;
        transform.position = _localPosition;

        SubmitMoveServerRpc(move);
    }

    [ServerRpc]
    public void SubmitMoveServerRpc(Vector3 move)
    {
        transform.position += move * Time.deltaTime * _speed;
        ConfirmPositionClientRpc(transform.position);
    }

    [ClientRpc]
    public void ConfirmPositionClientRpc(Vector3 serverPosition)
    {
        if (!IsOwner) return;
        var error = Vector3.Distance(_localPosition, serverPosition);
        if (error > 0.1f)
            _localPosition = Vector3.Lerp(_localPosition, serverPosition, 0.5f);
    }
}

优点：操作零延迟。缺点：需要实现纠错逻辑。

---

4. 网络性能优化

4.1 减少带宽

private float _lastSendTime;
private const float SendInterval = 0.05f;

private void FixedUpdate()
{
    if (Time.time - _lastSendTime < SendInterval) return;
    _lastSendTime = Time.time;
    SendPositionServerRpc(transform.position);
}

4.2 增量更新

private Vector3 _lastSentPosition;
private const float DeltaThreshold = 0.01f;

private void Update()
{
    if (!IsOwner) return;
    var currentPos = transform.position;
    if (Vector3.Distance(currentPos, _lastSentPosition) > DeltaThreshold)
    {
        _lastSentPosition = currentPos;
        SyncPositionServerRpc(currentPos);
    }
}

---

总结

• 三层架构：数据层 + 逻辑层 + 网络层 + 表现层，职责分离
• 房间系统：用 NetworkList 维护房间列表
• 三种同步：完全同步（防作弊）、客户端预测（低延迟）、插值同步（平滑）
• 优化手段：位置增量同步、可变速率、带宽压缩

下一篇将讲解 新版 Input System 深入，从 Input Manager 迁移到现代化的输入处理方案。