From 2fcf1af21b5b263e0fe6885ff7d85b06926d65b8 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@zdoom.fake>
Date: Mon, 8 Nov 2010 17:24:27 +0000
Subject: [PATCH] - added a $musicalias command to SNDINFO that allows
 remapping of music tracks. Mapping to 'none' means that starting the remapped
 song will have no effect at all. There's one limitation though: If you load a
 WAD with the same music name after the one with the SNDINFO lump the mapping
 will be ignored. This is so that music resources can use this command without
 interfering with WADs that replace the music with their own.

SVN r3002 (trunk)
---
 src/s_advsound.cpp | 30 ++++++++++++++++++++++++++++++
 src/s_sound.cpp    | 10 +++++++++-
 src/s_sound.h      |  2 ++
 3 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/src/s_advsound.cpp b/src/s_advsound.cpp
index 240498f0c9..c194d74482 100644
--- a/src/s_advsound.cpp
+++ b/src/s_advsound.cpp
@@ -149,6 +149,7 @@ enum SICommands
 	SI_IfStrife,
 	SI_Rolloff,
 	SI_Volume,
+	SI_MusicAlias,
 };
 
 // Blood was a cool game. If Monolith ever releases the source for it,
@@ -183,6 +184,7 @@ struct FSavedPlayerSoundInfo
 };
 
 // This specifies whether Timidity or Windows playback is preferred for a certain song (only useful for Windows.)
+MusicAliasMap MusicAliases;
 MidiDeviceMap MidiDevices;
 
 // EXTERNAL FUNCTION PROTOTYPES --------------------------------------------
@@ -241,6 +243,7 @@ static const char *SICommandStrings[] =
 	"$ifstrife",
 	"$rolloff",
 	"$volume",
+	"$musicalias",
 	NULL
 };
 
@@ -254,6 +257,7 @@ static bool PlayerClassesIsSorted;
 static TArray<FPlayerClassLookup> PlayerClassLookups;
 static TArray<FPlayerSoundHashTable> PlayerSounds;
 
+
 static FString DefPlayerClassName;
 static int DefPlayerClass;
 
@@ -1285,6 +1289,32 @@ static void S_AddSNDINFO (int lump)
 				}
 				break;
 
+			case SI_MusicAlias: {
+				sc.MustGetString();
+				int lump = Wads.CheckNumForName(sc.String, ns_music);
+				if (lump >= 0)
+				{
+					// do not set the alias if a later WAD defines its own music of this name
+					int file = Wads.GetLumpFile(lump);
+					int sndifile = Wads.GetLumpFile(sc.LumpNum);
+					if (file > sndifile)
+					{
+						sc.MustGetString();
+						continue;
+					}
+				}
+				FName alias = sc.String;
+				sc.MustGetString();
+				FName mapped = sc.String;
+
+				// only set the alias if the lump it maps to exists.
+				if (mapped == NAME_None || Wads.CheckNumForName(sc.String, ns_music) >= 0)
+				{
+					MusicAliases[alias] = mapped;
+				}
+				}
+				break;
+
 			case SI_MidiDevice: {
 				sc.MustGetString();
 				FName nm = sc.String;
diff --git a/src/s_sound.cpp b/src/s_sound.cpp
index 95130d3090..bb85541c49 100644
--- a/src/s_sound.cpp
+++ b/src/s_sound.cpp
@@ -2386,8 +2386,16 @@ bool S_ChangeMusic (const char *musicname, int order, bool looping, bool force)
 		int offset = 0, length = 0;
 		int device = MDEV_DEFAULT;
 		MusInfo *handle = NULL;
+		FName musicasname = musicname;
 
-		int *devp = MidiDevices.CheckKey(FName(musicname));
+		FName *aliasp = MusicAliases.CheckKey(musicasname);
+		if (aliasp != NULL) 
+		{
+			musicname = (musicasname = *aliasp).GetChars();
+			if (musicasname == NAME_None) return true;
+		}
+
+		int *devp = MidiDevices.CheckKey(musicasname);
 		if (devp != NULL) device = *devp;
 
 		// Strip off any leading file:// component.
diff --git a/src/s_sound.h b/src/s_sound.h
index 5c2796d5b3..ee831bddfa 100644
--- a/src/s_sound.h
+++ b/src/s_sound.h
@@ -382,8 +382,10 @@ enum EMidiDevice
 	MDEV_GUS = 5,
 };
 
+typedef TMap<FName, FName> MusicAliasMap;
 typedef TMap<FName, int> MidiDeviceMap;
 
+extern MusicAliasMap MusicAliases;
 extern MidiDeviceMap MidiDevices;
 
 #endif