自学教程：C++ GetChanceAgainst函数代码示例

void ArenaTeam::MemberLost(Player * plr, uint32 againstRating){    // called for each participant of a match after losing    for(MemberList::iterator itr = m_members.begin(); itr !=  m_members.end(); ++itr)    {        if (itr->guid == plr->GetObjectGuid())        {            // update personal rating            float chance = GetChanceAgainst(itr->personal_rating, againstRating);            float K = (itr->personal_rating < 1000) ? 48.0f : 32.0f;            // calculate the rating modification (ELO system with k=32 or k=48 if rating<1000)            int32 mod = (int32)ceil(K * (0.0f - chance));                        if(againstRating <= sWorld.getConfig(CONFIG_UINT32_LOSERNOCHANGE) || itr->personal_rating <= sWorld.getConfig(CONFIG_UINT32_LOSERNOCHANGE))                mod = 0;            else if (itr->personal_rating <= sWorld.getConfig(CONFIG_UINT32_LOSERHALFCHANGE))                mod /= 2;            itr->ModifyPersonalRating(plr, mod, GetSlot());            // update matchmaker rating             chance = GetChanceAgainst(itr->matchmaker_rating, againstRating);            K = (itr->matchmaker_rating < 1000) ? 48.0f : 32.0f;            // calculate the rating modification (ELO system with k=32 or k=48 if rating<1000)            mod = (int32)ceil(K * (0.0f - chance));            itr->ModifyMatchmakerRating(plr,mod,GetType());            // update personal played stats            itr->games_week += 1;            itr->games_season += 1;            // update the unit fields            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_WEEK,  itr->games_week);            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_SEASON,  itr->games_season);            return;        }    }}

int32 ArenaTeam::WonAgainst(uint32 againstRating){    // called when the team has won    // 'chance' calculation - to beat the opponent    float chance = GetChanceAgainst(m_stats.rating, againstRating);    // calculate the rating modification (ELO system with k=32)    int32 mod = (int32)floor(32.0f * (1.0f - chance));    // modify the team stats accordingly    FinishGame(mod);    m_stats.wins_week += 1;    m_stats.wins_season += 1;    // return the rating change, used to display it on the results screen    return mod;}

void ArenaTeam::MemberWon(Player * plr, uint32 againstRating){    // called for each participant after winning a match    for(MemberList::iterator itr = m_members.begin(); itr !=  m_members.end(); ++itr)    {        if (itr->guid == plr->GetObjectGuid())        {            // FG: attempt to prevent "win trading" - dont give reward to winner if player with same IP is in opposite team            Map::PlayerList const& plist = plr->GetMap()->GetPlayers();            for(Map::PlayerList::const_iterator pit = plist.begin(); pit != plist.end(); ++pit)            {                Player *pp = pit->getSource();                if( !(pp && pp->IsSessionValid() && plr->IsSessionValid()) )                    return; // something wrong                if(pp->GetSession()->GetIP() == plr->GetSession()->GetIP() && pp->IsHostileTo(plr))                {                    ChatHandler(plr).PSendSysMessage(11110, pp->GetName());                    return;                }            }            // FG: -end-            // update personal rating            float chance = GetChanceAgainst(itr->personal_rating, againstRating);            float K = (itr->personal_rating < 1000) ? 48.0f : 32.0f;            // calculate the rating modification (ELO system with k=32 or k=48 if rating<1000)            int32 mod = (int32)floor(K* (1.0f - chance));            itr->ModifyPersonalRating(plr, mod, GetSlot());            // update personal stats            itr->games_week += 1;            itr->games_season += 1;            itr->wins_season += 1;            itr->wins_week += 1;            // update unit fields            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_WEEK, itr->games_week);            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_SEASON, itr->games_season);            return;        }    }}

void ArenaTeam::MemberWon(Player * plr, uint32 againstRating){    // We handle personal rating for Solo Queue in Arena Team win or lost function    if (GetType() == ARENA_TEAM_5v5)        return;    // called for each participant after winning a match    for (MemberList::iterator itr = m_members.begin(); itr != m_members.end(); ++itr)    {        if (itr->guid == plr->GetGUID())        {            // update personal rating            float chance = GetChanceAgainst(itr->personal_rating, againstRating);            int32 mod = (int32)floor(32.0f * (1.0f - chance));            if (GetType() == ARENA_TEAM_2v2)            {                if (m_stats.rating < 1850)                    mod += 2;                if (mod == 30)                    mod++;                if (mod < 3)                    mod = 3;            }            itr->ModifyPersonalRating(plr, mod, GetSlot());            // update personal stats            itr->games_week +=1;            itr->games_season +=1;            itr->wins_season += 1;            itr->wins_week += 1;            // update unit fields            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_WEEK, itr->games_week);            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_SEASON, itr->games_season);            return;        }    }}

int32 ArenaTeam::OfflineMemberLost(uint64 guid, uint32 againstRating){    // called for offline player after ending rated arena match!    for(MemberList::iterator itr = m_members.begin(); itr !=  m_members.end(); ++itr)    {        if (itr->guid == guid)        {            // update personal rating            float chance = GetChanceAgainst(itr->personal_rating, againstRating);            float K = (itr->personal_rating < 1000) ? 48.0f : 32.0f;            // calculate the rating modification (ELO system with k=32 or k=48 if rating<1000)            int32 mod = (int32)ceil(K * (0.0f - chance));            if (int32(itr->personal_rating) + mod < 0)                itr->personal_rating = 0;            else                itr->personal_rating += mod;            // update personal played stats            itr->games_week += 1;            itr->games_season += 1;            return mod;        }    }return 0;}

void ArenaTeam::MemberWon(Player* plr, uint32 againstRating){    // called for each participant after winning a match    for (MemberList::iterator itr = m_members.begin(); itr !=  m_members.end(); ++itr)    {        if (itr->guid == plr->GetObjectGuid())        {            // update personal rating            float chance = GetChanceAgainst(itr->personal_rating, againstRating);            int32 mod = (int32)floor(32.0f * (1.0f - chance));            itr->ModifyPersonalRating(plr, mod, GetSlot());            // update personal stats            itr->games_week += 1;            itr->games_season += 1;            itr->wins_season += 1;            itr->wins_week += 1;            // update unit fields            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_WEEK, itr->games_week);            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_SEASON, itr->games_season);            return;        }    }}

void ArenaTeam::MemberLost(Player * plr, uint32 againstRating){    // called for each participant of a match after losing    for(MemberList::iterator itr = m_members.begin(); itr !=  m_members.end(); ++itr)    {        if(itr->guid == plr->GetGUID())        {            // update personal rating            float chance = GetChanceAgainst(itr->personal_rating, againstRating);            float K = (itr->personal_rating < 1000) ? 48.0f : 32.0f;            // calculate the rating modification (ELO system with k=32 or k=48 if rating<1000)            int32 mod = (int32)ceil(K * (0.0f - chance));            itr->ModifyPersonalRating(plr, mod, GetSlot());            // update personal played stats            itr->games_week += 1;            itr->games_season += 1;            // update the unit fields            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_WEEK,  itr->games_week);            plr->SetArenaTeamInfoField(GetSlot(), ARENA_TEAM_GAMES_SEASON,  itr->games_season);            return;        }    }}

void ArenaTeam::MemberWon(Player * plr, uint32 againstRating){    // called for each participant after winning a match    for(MemberList::iterator itr = members.begin(); itr !=  members.end(); ++itr)    {        if(itr->guid == plr->GetGUID())        {            // update personal rating            float chance = GetChanceAgainst(itr->personal_rating, againstRating);            int32 mod = (int32)floor(32.0f * (1.0f - chance));            itr->ModifyPersonalRating(plr, mod, GetSlot());            // update personal stats            itr->games_week +=1;            itr->games_season +=1;            itr->wins_season += 1;            itr->wins_week += 1;            // update unit fields            plr->SetUInt32Value(PLAYER_FIELD_ARENA_TEAM_INFO_1_1 + 6 * GetSlot() + 2, itr->games_week);            plr->SetUInt32Value(PLAYER_FIELD_ARENA_TEAM_INFO_1_1 + 6 * GetSlot() + 3, itr->games_season);            return;        }    }}

int32 ArenaTeam::GetRatingMod(uint32 ownRating, uint32 opponentRating, bool won /*, float confidence_factor*/){    // 'Chance' calculation - to beat the opponent    // This is a simulation. Not much info on how it really works    float chance = GetChanceAgainst(ownRating, opponentRating);    float won_mod = (won) ? 1.0f : 0.0f;    // Calculate the rating modification    float mod;    // TODO: Replace this hack with using the confidence factor (limiting the factor to 2.0f)    if (won && ownRating < 1300)    {        if (ownRating < 1000)            mod = 48.0f * (won_mod - chance);        else            mod = (24.0f + (24.0f * (1300.0f - float(ownRating)) / 300.0f)) * (won_mod - chance);    }    else        mod = 24.0f * (won_mod - chance);    return (int32)ceil(mod);}

int32 ArenaTeam::GetRatingMod(uint32 own_rating, uint32 enemy_rating, bool won, bool calculating_mmr){    // 'chance' calculation - to beat the opponent    float chance = GetChanceAgainst(own_rating, enemy_rating);    float won_mod = (won) ? 1.0f : 0.0f;    // calculate the rating modification    // simulation on how it works. Not much info on how it really works    float mod;    if (won && !calculating_mmr)    {        if (own_rating < 1000)            mod = 48.0f * (won_mod - chance);        else if (own_rating < 1300)            mod = (24.0f + (24.0f * (1300.0f - int32(own_rating)) / 300.0f)) * (won_mod - chance);        else            mod = 24.0f * (won_mod - chance);    }    else        mod = 24.0f * (won_mod - chance);    return (int32)ceil(mod);}

int32 ArenaTeam::LostAgainst(uint32 againstRating){    // called when the team has lost    //'chance' calculation - to loose to the opponent    float chance = GetChanceAgainst(stats.rating,againstRating);    // calculate the rating modification (ELO system with k=32)    int32 mod = (int32)ceil(32.0f * (0.0f - chance));    // modify the team stats accordingly    stats.rating += mod;    stats.games_week += 1;    stats.games_season += 1;    //update team's rank    stats.rank = 1;    ObjectMgr::ArenaTeamMap::iterator i = objmgr.GetArenaTeamMapBegin();    for ( ; i != objmgr.GetArenaTeamMapEnd(); ++i)    {        if (i->second->GetType() == this->Type && i->second->GetStats().rating > stats.rating)            ++stats.rank;    }    // return the rating change, used to display it on the results screen    return mod;}

int32 ArenaTeam::GetPersonalRatingMod(int32 base_rating, uint32 own_rating, uint32 enemy_rating){    float chance = GetChanceAgainst(own_rating, enemy_rating);    chance *= 2.0f;    return (int32)ceil(float(base_rating) * chance);}