Sync timing all players in room without PhotonView. (PUN2 with Unity)

_License

zLib/libpng License

Copyright (c) 2019 Hassaku

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   1. The origin of this software must not be misrepresented; you must not
   claim that you wrote the original software. If you use this software
   in a product, an acknowledgment in the product documentation would be
   appreciated but is not required.

   2. Altered source versions must be plainly marked as such, and must not be
   misrepresented as being the original software.

   3. This notice may not be removed or altered from any source
   distribution.

TimingSync.cs

using ExitGames.Client.Photon;
using Photon.Pun;
using Photon.Realtime;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

/// <summary>
/// PUN2 ルーム内タイミング合わせ
/// </summary>
/// <usage>
/// コールバックの登録は入室時、解除は退室時
/// public void OnCreateRoom(){
///     sync = new TimingSync();
///     PhotonNetwork.AddCallbackTarget(sync);
///     ...
/// }
/// 
/// public void OnLeftRoom(){
///     PhotonNetwork.RemoveCallbackTarget(sync);
/// }
/// 
/// //  タイミング合わせ
/// yield return sync.WaitForSync("Hoge", 30f);
/// </usage>
public class TimingSync : IOnEventCallback {

    //  環境によって変える
    private const byte SyncRequestCode = 102;

    private Dictionary<string, int> counters = new Dictionary<string, int>();

    public bool IsTimeout { get; set; }
    public bool IsDisconnected { get; set; }

    /// <summary>
    /// ルーム内プレイヤーのタイミング合わせを待つ
    /// </summary>
    /// <param name="identifier">タイミング識別子</param>
    /// <param name="timeout">タイムアウト時間</param>
    /// <returns></returns>
    public IEnumerator WaitForSync(string identifier, float timeout)
    {
        if (!counters.ContainsKey(identifier)) counters.Add(identifier, 0);
        if (!(PhotonNetwork.IsConnectedAndReady && PhotonNetwork.InRoom))
        {
            IsDisconnected = true;
            yield break;
        }

        PhotonNetwork.RaiseEvent(SyncRequestCode, identifier,
            new RaiseEventOptions
            {
                Receivers = ReceiverGroup.All,
            },
            new SendOptions
            {
                DeliveryMode = DeliveryMode.Reliable,
                Reliability = true,
            });
                
        float timer = 0f;

        while (true)
        {
            if (timer > timeout)
            {
                IsTimeout = true;
                break;
            }
            if (!(PhotonNetwork.IsConnectedAndReady && PhotonNetwork.InRoom))
            {
                IsDisconnected = true;
                break;
            }
            if(counters[identifier] == PhotonNetwork.CurrentRoom.PlayerCount)
            {
                break;
            }

            timer += Time.deltaTime;
            yield return null;
        }
        counters[identifier] = 0;
    }

    public void OnEvent(EventData photonEvent)
    {
        if(photonEvent.Code == SyncRequestCode)
        {
            string key = (string)photonEvent.CustomData;
            if (!counters.ContainsKey(key)) counters.Add(key, 0);
            counters[key]++;
        }
    }
}