Merge branch 'upstream' of https://github.com/Edward850/zdoom

src/d_main.cpp

@@ -1993,7 +1993,19 @@ static void D_DoomInit()
 
 	SetLanguageIDs ();
 
+	const char *v = Args->CheckValue("-rngseed");
+	if (v)
+	{
+		rngseed = staticrngseed = atoi(v);
+		use_staticrng = true;
+		Printf("D_DoomInit: Static RNGseed %d set.\n", rngseed);
+	}
+	else
+	{
 		rngseed = I_MakeRNGSeed();
+		use_staticrng = false;
+	}
+		
 	FRandom::StaticClearRandom ();
 
 	Printf ("M_LoadDefaults: Load system defaults.\n");

src/g_level.cpp

@@ -408,9 +408,11 @@ void G_InitNew (const char *mapname, bool bTitleLevel)
 
 	if (!savegamerestore)
 	{
-		if (!netgame)
+		if (!netgame && !demorecording && !demoplayback)
-		{ // [RH] Change the random seed for each new single player game
+		{
-			rngseed = rngseed + 1;
+			// [RH] Change the random seed for each new single player game
+			// [ED850] The demo already sets the RNG.
+			rngseed = use_staticrng ? staticrngseed : (rngseed + 1);
 		}
 		FRandom::StaticClearRandom ();
 		P_ClearACSVars(true);

src/m_random.cpp

@@ -96,6 +96,42 @@ FRandom M_Random;
 // Global seed. This is modified predictably to initialize every RNG.
 DWORD rngseed;
 
+// Static RNG marker. This is only used when the RNG is set for each new game.
+DWORD staticrngseed;
+bool use_staticrng;
+
+// Allows checking or staticly setting the global seed.
+CCMD(rngseed)
+{
+	if (argv.argc() == 1)
+	{
+		Printf("Usage: rngseed get|set|clear\n");
+		return;
+	}
+	if (stricmp(argv[1], "get") == 0)
+	{
+		Printf("rngseed is %d\n", rngseed);
+	}
+	else if (stricmp(argv[1], "set") == 0)
+	{
+		if (argv.argc() == 2)
+		{
+			Printf("You need to specify a value to set\n");
+		}
+		else
+		{
+			staticrngseed = atoi(argv[2]);
+			use_staticrng = true;
+			Printf("Static rngseed %d will be set for next game\n", staticrngseed);
+		}
+	}
+	else if (stricmp(argv[1], "clear") == 0)
+	{
+		use_staticrng = false;
+		Printf("Static rngseed cleared\n");
+	}
+}
+
 // PRIVATE DATA DEFINITIONS ------------------------------------------------
 
 FRandom *FRandom::RNGList;

src/m_random.h

@@ -215,6 +215,10 @@ private:
 
 extern DWORD rngseed;			// The starting seed (not part of state)
 
+extern DWORD staticrngseed;		// Static rngseed that can be set by the user
+extern bool use_staticrng;
+
+
 // M_Random can be used for numbers that do not affect gameplay
 extern FRandom M_Random;