毒圈

评评① 0 到 1 的大世界玩法模块：安全区收缩圈（吃鸡式缩圈）。 设计核心是服务器只发「关键帧」，客户端逐帧插值出整个收缩过程—— 服务器不用每帧广播，客户端断线重连后也能凭一对时间戳立刻对齐当前圈。 三态（静态圈/动态圈/无圈）由服务器协议字段直接驱动。

1. 工作清单

2. 理论：服务器权威关键帧 vs 客户端逐帧插值

2.1 数据流：一对时间戳驱动整个收缩

2.2 三态状态机：协议字段即状态

2.3 时间戳防御：为什么三重检查都返回 1

3. 代码片段

3.1 时间戳三重防御

Src\Game\Module\PoisonZone\PoisonZoneModel.ts:140-185

public GetProgress(): number {
    const dynamicData = this.GetDynamicPoisonZone();
    if (!dynamicData || this.CachedBeginTimeMs === undefined || this.CachedEndTimeMs === undefined) {
        return 0;
    }

    const currentTimeMs = Date.now();
    const beginTimeMs = this.CachedBeginTimeMs;
    const endTimeMs = this.CachedEndTimeMs;

    if (Number.isNaN(beginTimeMs) || Number.isNaN(endTimeMs)) {
        Log.Error(ELogModule.Level, ELogAuthor.ZZB, '毒圈-时间戳无效: ',
            ['beginTimeMs', beginTimeMs], ['endTimeMs', endTimeMs]);
        return 1;
    }

    if (beginTimeMs === endTimeMs) {
        Log.Error(ELogModule.Level, ELogAuthor.ZZB, '毒圈-开始时间和结束时间相同，异常行为: ', ...);
        return 1;
    }

    if (beginTimeMs > endTimeMs) {
        Log.Error(ELogModule.Level, ELogAuthor.ZZB, '毒圈-开始时间大于结束时间，异常行为: ', ...);
        return 1;
    }

    const totalDuration = endTimeMs - beginTimeMs;
    return Math.min(Math.max((currentTimeMs - beginTimeMs) / totalDuration, 0), 1);
}

3.2 三段式状态计算：终点态 / 起点态 / 线性插值

Src\Game\Module\PoisonZone\PoisonZoneModel.ts:203-235

private CalculateDynamicState(): ICurrentPoisonZoneState {
    const dynamicData = this.GetDynamicPoisonZone();
    if (!dynamicData || this.CachedBeginTimeMs === undefined || this.CachedEndTimeMs === undefined) {
        return this.GetInvalidState();
    }

    const currentTimeMs = Date.now();

    if (currentTimeMs >= endTimeMs) {                       // 段1：已过结束时间 → 终点态
        return { Position: dynamicData.endPos, Radius: dynamicData.endRadius, IsValid: true, ... };
    }

    if (currentTimeMs <= beginTimeMs) {                       // 段2：未到开始时间 → 起点态
        return { Position: dynamicData.beginPos, Radius: dynamicData.beginRadius, IsValid: true, ... };
    }

    const progress = this.GetProgress();                     // 段3：进行中 → 插值
    return this.InterpolateState(dynamicData, progress);
}

3.3 每帧插值 + 写 MPC

Src\Game\Module\PoisonZone\PoisonZoneView.ts:30-69

public Update(): void {
    if (!this.PoisonZoneInstance) { return; }

    const poisonZoneType = ControllerHolder.PoisonZoneController.GetPoisonZoneType();
    if (poisonZoneType !== EPoisonZoneType.Dynamic) { return; }   // 静态圈不进每帧

    const progress = ControllerHolder.PoisonZoneController.GetProgress();
    if (Number.isNaN(progress)) {
        Log.Error(ELogModule.Level, ELogAuthor.ZZB, '毒圈-更新进度: 进度值无效');
        return;
    }

    if (progress >= 1) {
        if (!this.IsDynamicPoisonZoneCompleted) {
            this.IsDynamicPoisonZoneCompleted = true;           // 完成时打一次日志
        } else {
            return;                                        // 已定格，停止重算
        }
    }

    const state = ControllerHolder.PoisonZoneController.GetCurrentState();
    const position = state.Position;
    if (position) {
        const newLocation = new UE.Vector(position.x, position.y, position.z);
        this.PoisonZoneInstance.K2_SetActorLocation(newLocation, false, undefined, true);
    }

    const beginRadius = state.BeginRadius ?? state.Radius;
    const endRadius = state.EndRadius ?? state.Radius;
    const currentRadius = beginRadius + (endRadius - beginRadius) * progress;

    this.SetActorScale(this.PoisonZoneInstance, currentRadius);
    this.UpdatePoisonZoneMaterialParam(position, currentRadius);
}

3.4 三态分发 + default 显式报错

Src\Game\Module\PoisonZone\PoisonZoneController.ts:72-108

private readonly NetWorldPoisonZoneUpdateNotify = (notify: Game.Protocol.WorldPoisonZoneUpdateSCNotify): void => {
    if (!notify || !notify.poisonZoneInfo) {
        Log.Error(ELogModule.Level, ELogAuthor.ZZB, '毒圈-服务器同步数据无效');
        return;
    }
    this.Model?.SetInfo(notify.poisonZoneInfo);
    this.OnPoisonZoneStateChanged();
};

private OnPoisonZoneStateChanged(): void {
    switch (this.GetPoisonZoneType()) {
        case EPoisonZoneType.Static:
            this.View.Create(this.GetCurrentState().Position, this.GetCurrentState().Radius, true);
            break;
        case EPoisonZoneType.Dynamic:
            this.View.Create(this.GetCurrentState().Position, fn">GetCurrentState().Radius, false);   // false=不销毁重建
            break;
        case EPoisonZoneType.None:
            this.View.Destroy();
            this.RemoveScreenEffect();
            break;
        default:
            Log.Error(ELogModule.Level, ELogAuthor.ZZB, '毒圈-未知毒圈类型');
            break;
    }
}

3.5 Action 注册链：三个圈操作全是服务器实现

Src\UniverseEditor\Common\Operation\Action.ts:445-458

//#region ---------------- 毒圈相关 ----------------
[EAction.CreatePoisonZone]: {
    Context: ['levelPlay'],
    ImplementType: 'Server',
},
[EAction.ShrinkPoisonZone]: {
    Context: ['levelPlay'],
    ImplementType: 'Server',
},
[EAction.DestroyPoisonZone]: {
    Context: ['levelPlay'],
    ImplementType: 'Server',
},
//#endregion ---------------- 毒圈相关 ----------------

4. 面试怎么讲