--------------------------------------------------------------------------------
////////////////////////////////SERVER//////////////////////////////////////////
--------------------------------------------------------------------------------
///ServerGameLogic.h\\\
float       gameStartTime_;
__int64     gameStartUtcTime_;
__int64     GetUtcGameTime();

///ServerGameLogic.cpp\\\
void ServerGameLogic::Init(const GBGameInfo& ginfo, uint32_t creatorID) //při spuštění serveru
{
    //blablabla

    //zde server inicializuje čas (reálný?)
    // init game time
    gameStartTime_     = r3dGetTime(); // - nevim přesně co dělá r3dGetTime() - tuším, že měří čas od dané inicializace

    __int64 utcTime = GetUtcGameTime();
    struct tm* tm = _gmtime64(&utcTime); // - struct tm - struktura pro lepší práci s časem - převod na hodiny, minuty, atd.
    r3d_assert(tm);

    char buf[128];
    asctime_s(buf, sizeof(buf), tm);
    r3dOutToLog("Server time is %s", buf); // - vypíše tm ve formátu DEN MĚSÍC DEN (DATUM) HH:MM:SS ROK -> obsahuje převod času

    //blablabla inicializace serveru - nezajímavé věci

    return;
}
///////////////////////////////
část paketu PKT_C2S_JoinGameReq
PKT_S2C_JoinGameAns_s n;
//blablabla
n.gameTime     = GetUtcGameTime(); // - posíláme klientovi informaci o čase
//blablabla

///////////////////////////////
__int64 ServerGameLogic::GetUtcGameTime()
{
    // "world time start" offset, so gametime at 1st sep 2012 will be in 2018 range
    struct tm toff = {0};
    toff.tm_year   = 2011-1900;
    toff.tm_mon    = 6;
    toff.tm_mday   = 1;
    toff.tm_isdst  = -1; // A value less than zero to have the C run-time library code compute whether standard time or daylight saving time is in effect.
    __int64 secs0 = _mkgmtime64(&toff); // world start time
    __int64 secs1 = _time64(&secs1);    // current UTC time

    // reassemble time, with speedup factor
    return secs0 + (secs1 - secs0) * (__int64)GPP_Data.c_iGameTimeCompression;
}
--------------------------------------------------------------------------------
////////////////////////////////CLIENT//////////////////////////////////////////
--------------------------------------------------------------------------------
///ClientGameLogic.h\\\
__int64     gameStartUtcTime_;
float       gameStartTime_;
__int64     GetServerGameTime() const;
void        UpdateTimeOfDay();

///ClientGameLogic.cpp\\\
část paketu PKT_C2S_JoinGameAns
//blablabla
gameStartUtcTime_ = n.gameTime;
gameStartTime_    = r3dGetTime();
UpdateTimeOfDay();
//blablabla

__int64 ClientGameLogic::GetServerGameTime() const
{
    float secs = (r3dGetTime() - gameStartTime_) * (float)GPP->c_iGameTimeCompression;
    __int64 gameUtcTime = gameStartUtcTime_ + __int64(secs);
    return gameUtcTime;
}

void ClientGameLogic::UpdateTimeOfDay()
{
    //blablabla
    __int64 gameUtcTime = GetServerGameTime();
    struct tm* tm = _gmtime64(&gameUtcTime);
    r3d_assert(tm);

    r3dGameLevel::Environment.__CurTime  = (float)tm->tm_hour + (float)tm->tm_min / 59.0f;
    //do not add seconds, much shadow flicker
    //r3dGameLevel::Environment.__CurTime += (float)tm->tm_sec / (59.0f * 59.0f);

    // reset shadow cache if environment time is changed
    if(fabs(r3dGameLevel::Environment.__CurTime - lastShadowCacheReset_) > 0.01f)
    {
        //r3dOutToLog("Server time: %f %d %d %d %d:%d\n", r3dGameLevel::Environment.__CurTime, tm->tm_mon, tm->tm_mday, 1900 + tm->tm_year, tm->tm_hour, tm->tm_min);
        lastShadowCacheReset_ = r3dGameLevel::Environment.__CurTime;
        ResetShadowCache();
    }
}

čas je zobrazován v ESC menu
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
tj. uvedeno v HUDPause.cpp jako funkce SetTime(__int64 utcTime) - dosazujeme gameUtcTime tedy GetServerGameTime()