Introduce UseMultiplayerQuests

Source/diablo.cpp

@@ -2745,10 +2745,10 @@ void LoadGameLevel(bool firstflag, lvl_entry lvldir)
 				for (int y = 0; y < DMAXY; y++)
 					UpdateAutomapExplorer({ x, y }, MAP_EXP_SELF);
 		}
-		if (!gbIsMultiplayer)
-			ResyncQuests();
-		else
+		if (UseMultiplayerQuests())
 			ResyncMPQuests();
+		else
+			ResyncQuests();
 	} else {
 		LoadSetMap();
 		IncProgress();
@@ -2791,8 +2791,11 @@ void LoadGameLevel(bool firstflag, lvl_entry lvldir)
 		} else {
 			LoadLevel();
 		}
-		if (gbIsMultiplayer)
+		if (gbIsMultiplayer) {
 			DeltaLoadLevel();
+			if (!UseMultiplayerQuests())
+				ResyncQuests();
+		}
 
 		InitMissiles();
 		IncProgress();

Source/msg.cpp

@@ -423,14 +423,15 @@ byte *DeltaExportJunk(byte *dst)
 
 	int q = 0;
 	for (auto &quest : Quests) {
-		if (!QuestsData[quest._qidx].isSinglePlayerOnly) {
-			sgJunk.quests[q].qlog = quest._qlog ? 1 : 0;
-			sgJunk.quests[q].qstate = quest._qactive;
-			sgJunk.quests[q].qvar1 = quest._qvar1;
-			memcpy(dst, &sgJunk.quests[q], sizeof(MultiQuests));
-			dst += sizeof(MultiQuests);
-			q++;
+		if (QuestsData[quest._qidx].isSinglePlayerOnly && UseMultiplayerQuests()) {
+			continue;
 		}
+		sgJunk.quests[q].qlog = quest._qlog ? 1 : 0;
+		sgJunk.quests[q].qstate = quest._qactive;
+		sgJunk.quests[q].qvar1 = quest._qvar1;
+		memcpy(dst, &sgJunk.quests[q], sizeof(MultiQuests));
+		dst += sizeof(MultiQuests);
+		q++;
 	}
 
 	return dst;
@@ -450,11 +451,12 @@ void DeltaImportJunk(const byte *src)
 
 	int q = 0;
 	for (int qidx = 0; qidx < MAXQUESTS; qidx++) {
-		if (!QuestsData[qidx].isSinglePlayerOnly) {
-			memcpy(&sgJunk.quests[q], src, sizeof(MultiQuests));
-			src += sizeof(MultiQuests);
-			q++;
+		if (QuestsData[qidx].isSinglePlayerOnly && UseMultiplayerQuests()) {
+			continue;
 		}
+		memcpy(&sgJunk.quests[q], src, sizeof(MultiQuests));
+		src += sizeof(MultiQuests);
+		q++;
 	}
 }
 
@@ -2537,7 +2539,7 @@ void DeltaSyncJunk()
 
 	int q = 0;
 	for (auto &quest : Quests) {
-		if (QuestsData[quest._qidx].isSinglePlayerOnly) {
+		if (QuestsData[quest._qidx].isSinglePlayerOnly && UseMultiplayerQuests()) {
 			continue;
 		}
 		if (sgJunk.quests[q].qstate != QUEST_INVALID) {

Source/quests.cpp

@@ -249,7 +249,7 @@ void InitQuests()
 		quest._qlog = false;
 		quest._qmsg = questData._qdmsg;
 
-		if (!gbIsMultiplayer) {
+		if (!UseMultiplayerQuests()) {
 			quest._qlevel = questData._qdlvl;
 			quest._qactive = QUEST_INIT;
 		} else if (!questData.isSinglePlayerOnly) {
@@ -258,7 +258,7 @@ void InitQuests()
 		}
 	}
 
-	if (!gbIsMultiplayer && *sgOptions.Gameplay.randomizeQuests) {
+	if (!UseMultiplayerQuests() && *sgOptions.Gameplay.randomizeQuests) {
 		// Quests are set from the seed used to generate level 16.
 		InitialiseQuestPools(glSeedTbl[15], Quests);
 	}
@@ -274,7 +274,7 @@ void InitQuests()
 	if (Quests[Q_ROCK]._qactive == QUEST_NOTAVAIL)
 		Quests[Q_ROCK]._qvar2 = 2;
 	Quests[Q_LTBANNER]._qvar1 = 1;
-	if (gbIsMultiplayer)
+	if (UseMultiplayerQuests())
 		Quests[Q_BETRAYER]._qvar1 = 2;
 }
 
@@ -804,6 +804,11 @@ void SetMultiQuest(int q, quest_state s, bool log, int v1, int v2)
 	quest._qvar2 = v2;
 }
 
+bool UseMultiplayerQuests()
+{
+	return gbIsMultiplayer;
+}
+
 bool Quest::IsAvailable()
 {
 	if (setlevel)
@@ -812,7 +817,7 @@ bool Quest::IsAvailable()
 		return false;
 	if (_qactive == QUEST_NOTAVAIL)
 		return false;
-	if (gbIsMultiplayer && QuestsData[_qidx].isSinglePlayerOnly)
+	if (QuestsData[_qidx].isSinglePlayerOnly && UseMultiplayerQuests())
 		return false;
 
 	return true;

Source/quests.h

@@ -104,6 +104,7 @@ void QuestlogDown();
 void QuestlogEnter();
 void QuestlogESC();
 void SetMultiQuest(int q, quest_state s, bool log, int v1, int v2);
+bool UseMultiplayerQuests();
 
 /* rdata */
 extern QuestData QuestsData[];