Capture the level seed and use it to skip failed dungeon layouts

Source/control.cpp

@@ -536,7 +536,7 @@ std::string TextCmdLevelSeed(const std::string_view parameter)
 
 	return StrCat(
 	    "Seedinfo for ", levelType, " ", currlevel, "\n",
-	    "seed: ", glSeedTbl[currlevel], "\n",
+	    "seed: ", DungeonSeeds[currlevel], "\n",
 #ifdef _DEBUG
 	    "Mid1: ", glMid1Seed[currlevel], "\n",
 	    "Mid2: ", glMid2Seed[currlevel], "\n",
@@ -546,7 +546,7 @@ std::string TextCmdLevelSeed(const std::string_view parameter)
 	    "\n",
 	    gameId, " ", mode, "\n",
 	    questPool, " quests: ", questFlags, "\n",
-	    "Storybook: ", glSeedTbl[16]);
+	    "Storybook: ", DungeonSeeds[16]);
 }
 
 std::vector<TextCmdItem> TextCmdList = {

Source/diablo.cpp

@@ -106,7 +106,8 @@
 
 namespace devilution {
 
-uint32_t glSeedTbl[NUMLEVELS];
+uint32_t DungeonSeeds[NUMLEVELS];
+std::optional<uint32_t> LevelSeeds[NUMLEVELS];
 Point MousePosition;
 bool gbRunGame;
 bool gbRunGameResult;
@@ -1339,7 +1340,7 @@ void LoadAllGFX()
  */
 void CreateLevel(lvl_entry entry)
 {
-	CreateDungeon(glSeedTbl[currlevel], entry);
+	CreateDungeon(DungeonSeeds[currlevel], entry);
 
 	switch (leveltype) {
 	case DTYPE_TOWN:
@@ -2837,7 +2838,7 @@ void LoadGameLevel(bool firstflag, lvl_entry lvldir)
 	if (pcurs > CURSOR_HAND && pcurs < CURSOR_FIRSTITEM) {
 		NewCursor(CURSOR_HAND);
 	}
-	SetRndSeed(glSeedTbl[currlevel]);
+	SetRndSeed(DungeonSeeds[currlevel]);
 	IncProgress();
 	MakeLightTable();
 	SetDungeonMicros();
@@ -2857,12 +2858,12 @@ void LoadGameLevel(bool firstflag, lvl_entry lvldir)
 		InitAutomapOnce();
 	}
 	if (!setlevel) {
-		SetRndSeed(glSeedTbl[currlevel]);
+		SetRndSeed(DungeonSeeds[currlevel]);
 	} else {
 		// Maps are not randomly generated, but the monsters max hitpoints are.
 		// So we need to ensure that we have a stable seed when generating quest/set-maps.
 		// For this purpose we reuse the normal dungeon seeds.
-		SetRndSeed(glSeedTbl[static_cast<size_t>(setlvlnum)]);
+		SetRndSeed(DungeonSeeds[static_cast<size_t>(setlvlnum)]);
 	}
 
 	if (leveltype == DTYPE_TOWN) {
@@ -2894,7 +2895,7 @@ void LoadGameLevel(bool firstflag, lvl_entry lvldir)
 		CreateLevel(lvldir);
 		IncProgress();
 		LoadLevelSOLData();
-		SetRndSeed(glSeedTbl[currlevel]);
+		SetRndSeed(DungeonSeeds[currlevel]);
 
 		if (leveltype != DTYPE_TOWN) {
 			GetLevelMTypes();
@@ -2942,7 +2943,7 @@ void LoadGameLevel(bool firstflag, lvl_entry lvldir)
 				visited = visited || player._pLvlVisited[currlevel];
 		}
 
-		SetRndSeed(glSeedTbl[currlevel]);
+		SetRndSeed(DungeonSeeds[currlevel]);
 
 		if (leveltype != DTYPE_TOWN) {
 			if (firstflag || lvldir == ENTRY_LOAD || !myPlayer._pLvlVisited[currlevel] || gbIsMultiplayer) {

Source/diablo.h

@@ -58,7 +58,8 @@ enum class MouseActionType : uint8_t {
 	OperateObject,
 };
 
-extern uint32_t glSeedTbl[NUMLEVELS];
+extern uint32_t DungeonSeeds[NUMLEVELS];
+extern std::optional<uint32_t> LevelSeeds[NUMLEVELS];
 extern Point MousePosition;
 extern DVL_API_FOR_TEST bool gbRunGame;
 extern bool gbRunGameResult;

Source/levels/drlg_l1.cpp

@@ -1165,6 +1165,9 @@ bool PlaceStairs(lvl_entry entry)
 
 void GenerateLevel(lvl_entry entry)
 {
+	if (LevelSeeds[currlevel])
+		SetRndSeed(*LevelSeeds[currlevel]);
+
 	size_t minarea = 761;
 	switch (currlevel) {
 	case 1:
@@ -1181,6 +1184,7 @@ void GenerateLevel(lvl_entry entry)
 		DRLG_InitTrans();
 
 		do {
+			LevelSeeds[currlevel] = GetLCGEngineState();
 			FirstRoom();
 		} while (FindArea() < minarea);
 

Source/levels/drlg_l2.cpp

@@ -2669,7 +2669,11 @@ bool PlaceStairs(lvl_entry entry)
 
 void GenerateLevel(lvl_entry entry)
 {
+	if (LevelSeeds[currlevel])
+		SetRndSeed(*LevelSeeds[currlevel]);
+
 	while (true) {
+		LevelSeeds[currlevel] = GetLCGEngineState();
 		nRoomCnt = 0;
 		InitDungeonFlags();
 		DRLG_InitTrans();

Source/levels/drlg_l3.cpp

@@ -12,6 +12,7 @@
 #include "monster.h"
 #include "objdat.h"
 #include "objects.h"
+#include "player.h"
 #include "quests.h"
 
 namespace devilution {
@@ -1988,7 +1989,11 @@ bool PlaceStairs(lvl_entry entry)
 
 void GenerateLevel(lvl_entry entry)
 {
+	if (LevelSeeds[currlevel])
+		SetRndSeed(*LevelSeeds[currlevel]);
+
 	while (true) {
+		LevelSeeds[currlevel] = GetLCGEngineState();
 		InitDungeonFlags();
 		int x1 = GenerateRnd(20) + 10;
 		int y1 = GenerateRnd(20) + 10;

Source/levels/drlg_l4.cpp

@@ -13,6 +13,7 @@
 #include "monster.h"
 #include "multi.h"
 #include "objdat.h"
+#include "player.h"
 
 namespace devilution {
 
@@ -1138,11 +1139,15 @@ bool PlaceStairs(lvl_entry entry)
 
 void GenerateLevel(lvl_entry entry)
 {
+	if (LevelSeeds[currlevel])
+		SetRndSeed(*LevelSeeds[currlevel]);
+
 	while (true) {
 		DRLG_InitTrans();
 
 		constexpr size_t Minarea = 692;
 		do {
+			LevelSeeds[currlevel] = GetLCGEngineState();
 			InitDungeonFlags();
 			FirstRoom();
 			CloseOuterBorders();

Source/loadsave.cpp

@@ -2027,6 +2027,21 @@ void SaveHotkeys(SaveWriter &saveWriter, const Player &player)
 	file.WriteLE<uint8_t>(static_cast<uint8_t>(player._pRSplType));
 }
 
+void LoadLevelSeeds()
+{
+	LoadHelper file(OpenSaveArchive(gSaveNumber), "levelseeds");
+	if (!file.IsValid())
+		return;
+
+	for (int i = 0; i < giNumberOfLevels; i++) {
+		if (file.NextLE<uint8_t>() != 0) {
+			LevelSeeds[i] = file.NextLE<uint32_t>();
+		} else {
+			LevelSeeds[i] = std::nullopt;
+		}
+	}
+}
+
 void LoadHeroItems(Player &player)
 {
 	LoadHelper file(OpenSaveArchive(gSaveNumber), "heroitems");
@@ -2136,7 +2151,8 @@ void LoadGame(bool firstflag)
 		app_fatal(_("Player is on a Hellfire only level"));
 
 	for (uint8_t i = 0; i < giNumberOfLevels; i++) {
-		glSeedTbl[i] = file.NextBE<uint32_t>();
+		DungeonSeeds[i] = file.NextBE<uint32_t>();
+		LevelSeeds[i] = std::nullopt;
 		file.Skip(4); // Skip loading gnLevelTypeTbl
 	}
 
@@ -2304,6 +2320,18 @@ void LoadGame(bool firstflag)
 	gbIsHellfireSaveGame = gbIsHellfire;
 }
 
+void SaveLevelSeeds(SaveWriter &saveWriter)
+{
+	SaveHelper file(saveWriter, "levelseeds", giNumberOfLevels * (sizeof(uint8_t) + sizeof(uint32_t)));
+
+	for (int i = 0; i < giNumberOfLevels; i++) {
+		file.WriteLE<uint8_t>(LevelSeeds[i] ? 1 : 0);
+		if (LevelSeeds[i]) {
+			file.WriteLE<uint32_t>(*LevelSeeds[i]);
+		}
+	}
+}
+
 void SaveHeroItems(SaveWriter &saveWriter, Player &player)
 {
 	size_t itemCount = static_cast<size_t>(NUM_INVLOC) + InventoryGridCells + MaxBeltItems;
@@ -2418,7 +2446,7 @@ void SaveGameData(SaveWriter &saveWriter)
 	file.WriteBE<int32_t>(ActiveObjectCount);
 
 	for (uint8_t i = 0; i < giNumberOfLevels; i++) {
-		file.WriteBE<uint32_t>(glSeedTbl[i]);
+		file.WriteBE<uint32_t>(DungeonSeeds[i]);
 		file.WriteBE<int32_t>(getHellfireLevelType(GetLevelType(i)));
 	}
 
@@ -2554,7 +2582,7 @@ void SaveLevel(SaveWriter &saveWriter)
 	DoUnVision(myPlayer.position.tile, myPlayer._pLightRad); // fix for vision staying on the level
 
 	if (leveltype == DTYPE_TOWN)
-		glSeedTbl[0] = AdvanceRndSeed();
+		DungeonSeeds[0] = AdvanceRndSeed();
 
 	char szName[MaxMpqPathSize];
 	GetTempLevelNames(szName);

Source/lua/modules/dev/level.cpp

@@ -25,7 +25,7 @@ namespace {
 
 std::string ExportDun()
 {
-	const std::string levelName = StrCat(currlevel, "-", glSeedTbl[currlevel], ".dun");
+	const std::string levelName = StrCat(currlevel, "-", DungeonSeeds[currlevel], ".dun");
 	FILE *dunFile = OpenFile(levelName.c_str(), "ab");
 
 	WriteLE16(dunFile, DMAXX);
@@ -101,19 +101,20 @@ std::string DebugCmdResetLevel(uint8_t level, std::optional<int> seed)
 	DeltaClearLevel(level);
 
 	if (seed.has_value()) {
-		glSeedTbl[level] = *seed;
+		DungeonSeeds[level] = *seed;
+		LevelSeeds[level] = std::nullopt;
 		return StrCat("Successfully reset level ", level, " with seed ", *seed, ".");
 	}
 	return StrCat("Successfully reset level ", level, ".");
 }
 
 std::string DebugCmdLevelSeed(std::optional<uint8_t> level)
 {
-	constexpr size_t NumLevels = sizeof(glSeedTbl) / sizeof(glSeedTbl[0]);
+	constexpr size_t NumLevels = sizeof(DungeonSeeds) / sizeof(DungeonSeeds[0]);
 	if (level.has_value() && *level >= NumLevels) {
 		return StrCat("level out of range, max: ", NumLevels - 1);
 	}
-	return StrCat(glSeedTbl[level.value_or(currlevel)]);
+	return StrCat(DungeonSeeds[level.value_or(currlevel)]);
 }
 
 } // namespace

Source/msg.cpp

@@ -750,7 +750,7 @@ void DeltaLeaveSync(uint8_t bLevel)
 	if (!gbIsMultiplayer)
 		return;
 	if (leveltype == DTYPE_TOWN) {
-		glSeedTbl[0] = AdvanceRndSeed();
+		DungeonSeeds[0] = AdvanceRndSeed();
 		return;
 	}
 

Source/multi.cpp

@@ -791,7 +791,8 @@ bool NetInit(bool bSinglePlayer)
 	gnTickDelay = 1000 / sgGameInitInfo.nTickRate;
 
 	for (int i = 0; i < NUMLEVELS; i++) {
-		glSeedTbl[i] = AdvanceRndSeed();
+		DungeonSeeds[i] = AdvanceRndSeed();
+		LevelSeeds[i] = std::nullopt;
 	}
 	PublicGame = DvlNet_IsPublicGame();
 

Source/objects.cpp

@@ -1375,7 +1375,7 @@ void AddPedestalOfBlood(Object &pedestalOfBlood)
 
 void AddStoryBook(Object &storyBook)
 {
-	storyBook._oVar1 = (glSeedTbl[16] >> 16) % 3;
+	storyBook._oVar1 = (DungeonSeeds[16] >> 16) % 3;
 	if (currlevel == 4)
 		storyBook._oVar2 = StoryText[storyBook._oVar1][0];
 	else if (currlevel == 8)

Source/quests.cpp

@@ -275,7 +275,7 @@ void InitQuests()
 
 	if (!UseMultiplayerQuests() && *sgOptions.Gameplay.randomizeQuests) {
 		// Quests are set from the seed used to generate level 16.
-		InitialiseQuestPools(glSeedTbl[15], Quests);
+		InitialiseQuestPools(DungeonSeeds[15], Quests);
 	}
 
 	if (gbIsSpawn) {

Source/stores.cpp

@@ -2135,7 +2135,7 @@ void SetupTownStores()
 				l = i;
 		}
 	} else {
-		SetRndSeed(glSeedTbl[currlevel] * SDL_GetTicks());
+		SetRndSeed(DungeonSeeds[currlevel] * SDL_GetTicks());
 	}
 
 	l = std::clamp(l + 2, 6, 16);

test/fixtures/memory_map/levelSeed.txt

@@ -1,2 +1,2 @@
-R 32 glSeedTbl
+R 32 DungeonSeeds
 R 32 gnLevelTypeTbl