Decouple Golems from Players and use SpawnMonster for Golem

Author: obligaron

Source/missiles.cpp

@@ -2343,8 +2343,7 @@ void AddGolem(Missile &missile, AddMissileParameter &parameter)
 
 	// Is Golem alive?
 	if (golem != nullptr) {
-		if (&player == MyPlayer)
-			KillGolem(*golem);
+		KillGolem(*golem);
 		return;
 	}
 
@@ -2357,7 +2356,7 @@ void AddGolem(Missile &missile, AddMissileParameter &parameter)
 	if (!spawnPosition)
 		return;
 
-	SpawnGolem(player, *golem, *spawnPosition, missile);
+	SpawnGolem(player, *spawnPosition, missile);
 }
 
 void AddApocalypseBoom(Missile &missile, AddMissileParameter &parameter)

Source/monster.cpp

@@ -176,6 +176,7 @@ void InitMonster(Monster &monster, Direction rd, size_t typeIndex, Point positio
 	monster.goalVar2 = 0;
 	monster.goalVar3 = 0;
 	monster.pathCount = 0;
+	monster.enemy = 0;
 	monster.isInvalid = false;
 	monster.uniqueType = UniqueMonsterType::None;
 	monster.activeForTicks = 0;
@@ -3132,6 +3133,20 @@ void EnsureMonsterIndexIsActive(size_t monsterId)
 	}
 }
 
+void InitGolem(devilution::Monster &monster, uint8_t golemOwnerPlayerId, int16_t golemSpellLevel)
+{
+	monster.flags |= MFLAG_GOLEM;
+	monster.goalVar3 = static_cast<int8_t>(golemOwnerPlayerId);
+	const Player &player = Players[golemOwnerPlayerId];
+	monster.maxHitPoints = 2 * (320 * golemSpellLevel + player._pMaxMana / 3);
+	monster.hitPoints = monster.maxHitPoints;
+	monster.armorClass = 25;
+	monster.golemToHit = 5 * (golemSpellLevel + 8) + 2 * player.getCharacterLevel();
+	monster.minDamage = 2 * (golemSpellLevel + 4);
+	monster.maxDamage = 2 * (golemSpellLevel + 8);
+	UpdateEnemy(monster);
+}
+
 } // namespace
 
 tl::expected<size_t, std::string> AddMonsterType(_monster_id type, placeflag placeflag)
@@ -3640,21 +3655,24 @@ void SpawnMonster(Point position, Direction dir, size_t typeIndex, bool startSpe
 	ActiveMonsterCount += 1;
 	uint32_t seed = GetLCGEngineState();
 	// Update local state immediately to increase ActiveMonsterCount instantly (this allows multiple monsters to be spawned in one game tick)
-	InitializeSpawnedMonster(position, dir, typeIndex, monsterIndex, seed);
-	NetSendCmdSpawnMonster(position, dir, static_cast<uint16_t>(typeIndex), static_cast<uint16_t>(monsterIndex), seed);
+	InitializeSpawnedMonster(position, dir, typeIndex, monsterIndex, seed, 0, 0);
+	NetSendCmdSpawnMonster(position, dir, static_cast<uint16_t>(typeIndex), static_cast<uint16_t>(monsterIndex), seed, 0, 0);
 }
 
-void LoadDeltaSpawnedMonster(size_t typeIndex, size_t monsterId, uint32_t seed)
+void LoadDeltaSpawnedMonster(size_t typeIndex, size_t monsterId, uint32_t seed, uint8_t golemOwnerPlayerId, int16_t golemSpellLevel)
 {
 	SetRndSeed(seed);
 	EnsureMonsterIndexIsActive(monsterId);
 	WorldTilePosition position = GolemHoldingCell;
 	Monster &monster = Monsters[monsterId];
 	M_ClearSquares(monster);
 	InitMonster(monster, Direction::South, typeIndex, position);
+	if (monster.type().type == MT_GOLEM) {
+		InitGolem(monster, golemOwnerPlayerId, golemSpellLevel);
+	}
 }
 
-void InitializeSpawnedMonster(Point position, Direction dir, size_t typeIndex, size_t monsterId, uint32_t seed)
+void InitializeSpawnedMonster(Point position, Direction dir, size_t typeIndex, size_t monsterId, uint32_t seed, uint8_t golemOwnerPlayerId, int16_t golemSpellLevel)
 {
 	SetRndSeed(seed);
 	EnsureMonsterIndexIsActive(monsterId);
@@ -3677,10 +3695,14 @@ void InitializeSpawnedMonster(Point position, Direction dir, size_t typeIndex, s
 	monster.occupyTile(position, false);
 	InitMonster(monster, dir, typeIndex, position);
 
-	if (IsSkel(monster.type().type))
+	if (monster.type().type == MT_GOLEM) {
+		InitGolem(monster, golemOwnerPlayerId, golemSpellLevel);
 		StartSpecialStand(monster, dir);
-	else
+	} else if (IsSkel(monster.type().type)) {
+		StartSpecialStand(monster, dir);
+	} else {
 		M_StartStand(monster, dir);
+	}
 }
 
 void AddDoppelganger(Monster &monster)
@@ -4656,32 +4678,48 @@ void TalktoMonster(Player &player, Monster &monster)
 	}
 }
 
-void SpawnGolem(Player &player, Monster &golem, Point position, Missile &missile)
+void SpawnGolem(Player &player, Point position, Missile &missile)
 {
-	golem.occupyTile(position, false);
-	golem.position.tile = position;
-	golem.position.future = position;
-	golem.position.old = position;
-	golem.pathCount = 0;
-	golem.maxHitPoints = 2 * (320 * missile._mispllvl + player._pMaxMana / 3);
-	golem.hitPoints = golem.maxHitPoints;
-	golem.armorClass = 25;
-	golem.golemToHit = 5 * (missile._mispllvl + 8) + 2 * player.getCharacterLevel();
-	golem.minDamage = 2 * (missile._mispllvl + 4);
-	golem.maxDamage = 2 * (missile._mispllvl + 8);
-	golem.flags |= MFLAG_GOLEM;
-	golem.goalVar3 = player.getId();
-	StartSpecialStand(golem, Direction::South);
-	UpdateEnemy(golem);
-	if (&player == MyPlayer) {
-		NetSendCmdGolem(
-		    golem.position.tile.x,
-		    golem.position.tile.y,
-		    golem.direction,
-		    golem.enemy,
-		    golem.hitPoints,
-		    GetLevelForMultiplayer(player));
+	// The command is only executed for the level owner, to prevent desyncs in multiplayer.
+	if (!MyPlayer->isLevelOwnedByLocalClient())
+		return;
+
+	// Search monster index to use for the new golem
+	Monster *golem = nullptr;
+	// 1. Prefer MonsterIndex = PlayerIndex for vanilla compatibility
+	if (player.getId() < ReservedMonsterSlotsForGolems) {
+		Monster &reservedGolem = Monsters[player.getId()];
+		if (reservedGolem.position.tile == GolemHoldingCell || reservedGolem.hitPoints == 0)
+			golem = &reservedGolem;
+	}
+	// 2. Use reserved slots, so additional Monsters can spawn
+	if (golem == nullptr) {
+		for (int i = 0; i < ReservedMonsterSlotsForGolems; i++) {
+			Monster &reservedGolem = Monsters[player.getId()];
+			if (reservedGolem.position.tile == GolemHoldingCell || reservedGolem.hitPoints == 0) {
+				golem = &reservedGolem;
+				break;
+			}
+		}
+	}
+	// 3. Use normal monster slot
+	if (golem == nullptr) {
+		if (ActiveMonsterCount >= MaxMonsters)
+			return;
+		size_t monsterIndex = ActiveMonsters[ActiveMonsterCount];
+		ActiveMonsterCount += 1;
+		golem = &Monsters[monsterIndex];
 	}
+
+	if (golem == nullptr)
+		return;
+
+	size_t monsterIndex = golem->getId();
+	uint32_t seed = GetLCGEngineState();
+
+	// Update local state immediately to increase ActiveMonsterCount instantly (this allows multiple monsters to be spawned in one game tick)
+	InitializeSpawnedMonster(position, Direction::South, 0, monsterIndex, seed, player.getId(), missile._mispllvl);
+	NetSendCmdSpawnMonster(position, Direction::South, 0, static_cast<uint16_t>(monsterIndex), seed, player.getId(), static_cast<uint8_t>(missile._mispllvl));
 }
 
 bool CanTalkToMonst(const Monster &monster)

Source/monster.h

@@ -514,11 +514,11 @@ void SpawnMonster(Point position, Direction dir, size_t typeIndex, bool startSpe
 /**
  * @brief Loads data for a dynamically spawned monster when entering a level in multiplayer.
  */
-void LoadDeltaSpawnedMonster(size_t typeIndex, size_t monsterId, uint32_t seed);
+void LoadDeltaSpawnedMonster(size_t typeIndex, size_t monsterId, uint32_t seed, uint8_t golemOwnerPlayerId, int16_t golemSpellLevel);
 /**
  * @brief Initialize a spanwed monster (from a network message or from SpawnMonster-function).
  */
-void InitializeSpawnedMonster(Point position, Direction dir, size_t typeIndex, size_t monsterId, uint32_t seed);
+void InitializeSpawnedMonster(Point position, Direction dir, size_t typeIndex, size_t monsterId, uint32_t seed, uint8_t golemOwnerPlayerId, int16_t golemSpellLevel);
 void AddDoppelganger(Monster &monster);
 void ApplyMonsterDamage(DamageType damageType, Monster &monster, int damage);
 bool M_Talker(const Monster &monster);
@@ -569,7 +569,7 @@ bool IsGoat(_monster_id mt);
 void ActivateSkeleton(Monster &monster, Point position);
 Monster *PreSpawnSkeleton();
 void TalktoMonster(Player &player, Monster &monster);
-void SpawnGolem(Player &player, Monster &golem, Point position, Missile &missile);
+void SpawnGolem(Player &player, Point position, Missile &missile);
 bool CanTalkToMonst(const Monster &monster);
 uint8_t encode_enemy(Monster &monster);
 void decode_enemy(Monster &monster, uint8_t enemyId);

Source/msg.cpp

@@ -215,6 +215,8 @@ struct DObjectStr {
 struct DSpawnedMonster {
 	size_t typeIndex;
 	uint32_t seed;
+	uint8_t golemOwnerPlayerId;
+	int16_t golemSpellLevel;
 };
 
 struct DLevel {
@@ -733,19 +735,6 @@ size_t OnLevelData(uint8_t pnum, const TCmd *pCmd)
 	return wBytes + sizeof(message);
 }
 
-void DeltaSyncGolem(const TCmdGolem &message, const Player &player, uint8_t level)
-{
-	if (!gbIsMultiplayer)
-		return;
-
-	DMonsterStr &monster = GetDeltaLevel(level).monster[player.getId()];
-	monster.position.x = message._mx;
-	monster.position.y = message._my;
-	monster._mactive = UINT8_MAX;
-	monster._menemy = message._menemy;
-	monster.hitPoints = SDL_SwapLE32(message._mhitpoints);
-}
-
 void DeltaLeaveSync(uint8_t bLevel)
 {
 	if (!gbIsMultiplayer)
@@ -1770,31 +1759,6 @@ size_t OnMonstDeath(const TCmd *pCmd, Player &player)
 	return sizeof(message);
 }
 
-size_t OnAwakeGolem(const TCmd *pCmd, Player &player)
-{
-	const auto &message = *reinterpret_cast<const TCmdGolem *>(pCmd);
-	const Point position { message._mx, message._my };
-
-	if (gbBufferMsgs == 1) {
-		SendPacket(player, &message, sizeof(message));
-	} else if (InDungeonBounds(position)) {
-		if (!player.isOnActiveLevel()) {
-			DeltaSyncGolem(message, player, message._currlevel);
-		} else if (&player != MyPlayer) {
-			// Check if this player already has an active golem
-			for (auto &missile : Missiles) {
-				if (missile._mitype == MissileID::Golem && &Players[missile._misource] == &player) {
-					return sizeof(message);
-				}
-			}
-
-			AddMissile(player.position.tile, position, message._mdir, MissileID::Golem, TARGET_MONSTERS, player, 0, 1);
-		}
-	}
-
-	return sizeof(message);
-}
-
 size_t OnMonstDamage(const TCmd *pCmd, Player &player)
 {
 	const auto &message = *reinterpret_cast<const TCmdMonDamage *>(pCmd);
@@ -2370,10 +2334,15 @@ size_t OnSpawnMonster(const TCmd *pCmd, const Player &player)
 
 	size_t typeIndex = static_cast<size_t>(SDL_SwapLE16(message.typeIndex));
 	size_t monsterId = static_cast<size_t>(SDL_SwapLE16(message.monsterId));
+	uint8_t golemOwnerPlayerId = message.golemOwnerPlayerId;
+	if (golemOwnerPlayerId >= Players.size()) {
+		return sizeof(message);
+	}
+	uint8_t golemSpellLevel = std::min(message.golemSpellLevel, static_cast<uint8_t>(MaxSpellLevel + Players[golemOwnerPlayerId]._pISplLvlAdd));
 
 	DLevel &deltaLevel = GetDeltaLevel(player);
 
-	deltaLevel.spawnedMonsters[monsterId] = { typeIndex, message.seed };
+	deltaLevel.spawnedMonsters[monsterId] = { typeIndex, message.seed, golemOwnerPlayerId, golemSpellLevel };
 	// Override old monster delta information
 	auto &deltaMonster = deltaLevel.monster[monsterId];
 	deltaMonster.position = position;
@@ -2382,7 +2351,7 @@ size_t OnSpawnMonster(const TCmd *pCmd, const Player &player)
 	deltaMonster._mactive = 0;
 
 	if (player.isOnActiveLevel() && &player != MyPlayer)
-		InitializeSpawnedMonster(position, message.dir, typeIndex, monsterId, message.seed);
+		InitializeSpawnedMonster(position, message.dir, typeIndex, monsterId, message.seed, golemOwnerPlayerId, golemSpellLevel);
 	return sizeof(message);
 }
 
@@ -2678,7 +2647,8 @@ void DeltaLoadLevel()
 	DLevel &deltaLevel = GetDeltaLevel(localLevel);
 	if (leveltype != DTYPE_TOWN) {
 		for (auto &deltaSpawnedMonster : deltaLevel.spawnedMonsters) {
-			LoadDeltaSpawnedMonster(deltaSpawnedMonster.second.typeIndex, deltaSpawnedMonster.first, deltaSpawnedMonster.second.seed);
+			auto &monsterData = deltaSpawnedMonster.second;
+			LoadDeltaSpawnedMonster(deltaSpawnedMonster.second.typeIndex, deltaSpawnedMonster.first, monsterData.seed, monsterData.golemOwnerPlayerId, monsterData.golemSpellLevel);
 			assert(deltaLevel.monster[deltaSpawnedMonster.first].position.x != 0xFF);
 		}
 		for (size_t i = 0; i < MaxMonsters; i++) {
@@ -2807,21 +2777,7 @@ void NetSendCmd(bool bHiPri, _cmd_id bCmd)
 		NetSendLoPri(MyPlayerId, (std::byte *)&cmd, sizeof(cmd));
 }
 
-void NetSendCmdGolem(uint8_t mx, uint8_t my, Direction dir, uint8_t menemy, int hp, uint8_t cl)
-{
-	TCmdGolem cmd;
-
-	cmd.bCmd = CMD_AWAKEGOLEM;
-	cmd._mx = mx;
-	cmd._my = my;
-	cmd._mdir = dir;
-	cmd._menemy = menemy;
-	cmd._mhitpoints = hp;
-	cmd._currlevel = cl;
-	NetSendLoPri(MyPlayerId, (std::byte *)&cmd, sizeof(cmd));
-}
-
-void NetSendCmdSpawnMonster(Point position, Direction dir, uint16_t typeIndex, uint16_t monsterId, uint32_t seed)
+void NetSendCmdSpawnMonster(Point position, Direction dir, uint16_t typeIndex, uint16_t monsterId, uint32_t seed, uint8_t golemOwnerPlayerId, uint8_t golemSpellLevel)
 {
 	TCmdSpawnMonster cmd;
 
@@ -2832,6 +2788,8 @@ void NetSendCmdSpawnMonster(Point position, Direction dir, uint16_t typeIndex, u
 	cmd.typeIndex = SDL_SwapLE16(typeIndex);
 	cmd.monsterId = SDL_SwapLE16(monsterId);
 	cmd.seed = SDL_SwapLE32(seed);
+	cmd.golemOwnerPlayerId = golemOwnerPlayerId;
+	cmd.golemSpellLevel = golemSpellLevel;
 	NetSendHiPri(MyPlayerId, (std::byte *)&cmd, sizeof(cmd));
 }
 
@@ -3246,8 +3204,6 @@ size_t ParseCmd(uint8_t pnum, const TCmd *pCmd)
 		return OnWarp(pCmd, player);
 	case CMD_MONSTDEATH:
 		return OnMonstDeath(pCmd, player);
-	case CMD_AWAKEGOLEM:
-		return OnAwakeGolem(pCmd, player);
 	case CMD_MONSTDAMAGE:
 		return OnMonstDamage(pCmd, player);
 	case CMD_PLRDEAD:

Source/msg.h

@@ -393,10 +393,6 @@ enum _cmd_id : uint8_t {
 	//
 	// body (TCmdQuest)
 	CMD_SYNCQUEST,
-	// Spawn golem at target location.
-	//
-	// body (TCmdGolem)
-	CMD_AWAKEGOLEM,
 	// Enable mana shield of player (render).
 	//
 	// body (TCmd)
@@ -500,16 +496,6 @@ struct TCmdParam4 {
 	uint16_t wParam4;
 };
 
-struct TCmdGolem {
-	_cmd_id bCmd;
-	uint8_t _mx;
-	uint8_t _my;
-	Direction _mdir;
-	int8_t _menemy;
-	int32_t _mhitpoints;
-	uint8_t _currlevel;
-};
-
 struct TCmdSpawnMonster {
 	_cmd_id bCmd;
 	uint8_t x;
@@ -518,6 +504,8 @@ struct TCmdSpawnMonster {
 	uint16_t typeIndex;
 	uint16_t monsterId;
 	uint32_t seed;
+	uint8_t golemOwnerPlayerId;
+	uint8_t golemSpellLevel;
 };
 
 struct TCmdQuest {
@@ -743,8 +731,7 @@ void DeltaLoadLevel();
 /** @brief Clears last sent player command for the local player. This is used when a game tick changes. */
 void ClearLastSentPlayerCmd();
 void NetSendCmd(bool bHiPri, _cmd_id bCmd);
-void NetSendCmdGolem(uint8_t mx, uint8_t my, Direction dir, uint8_t menemy, int hp, uint8_t cl);
-void NetSendCmdSpawnMonster(Point position, Direction dir, uint16_t typeIndex, uint16_t monsterId, uint32_t seed);
+void NetSendCmdSpawnMonster(Point position, Direction dir, uint16_t typeIndex, uint16_t monsterId, uint32_t seed, uint8_t golemOwnerPlayerId, uint8_t golemSpellLevel);
 void NetSendCmdLoc(uint8_t playerId, bool bHiPri, _cmd_id bCmd, Point position);
 void NetSendCmdLocParam1(bool bHiPri, _cmd_id bCmd, Point position, uint16_t wParam1);
 void NetSendCmdLocParam2(bool bHiPri, _cmd_id bCmd, Point position, uint16_t wParam1, uint16_t wParam2);

Source/player.cpp

@@ -2809,16 +2809,10 @@ void SyncPlrKill(Player &player, DeathReason deathReason)
 
 void RemovePlrMissiles(const Player &player)
 {
-	if (leveltype != DTYPE_TOWN && &player == MyPlayer) {
-		Monster *golem = FindGolemForPlayer(player);
-		if (golem != nullptr) {
+	if (leveltype != DTYPE_TOWN) {
+		Monster *golem;
+		while ((golem = FindGolemForPlayer(player)) != nullptr) {
 			KillGolem(*golem);
-			AddCorpse(golem->position.tile, golem->type().corpseId, golem->direction);
-			int mx = golem->position.tile.x;
-			int my = golem->position.tile.y;
-			dMonster[mx][my] = 0;
-			golem->isInvalid = true;
-			DeleteMonsterList();
 		}
 	}