mapheader_t: PositionMusic property

A little off-piste, but a trivial addition since I'm changing this part of the code.
- Plays in Position outside of Encore
- Shows up first in the Sound Test sequence for that map

src/deh_soc.c

@@ -1211,6 +1211,18 @@ void readlevelheader(MYFILE *f, char * name)
 					mapheaderinfo[num]->associatedmus_size = j;
 				}
 			}
+			else if (fastcmp(word, "POSITIONMUSIC"))
+			{
+				if (fastcmp(word2, "NONE"))
+				{
+					mapheaderinfo[num]->positionmus[0] = 0; // becomes empty string
+				}
+				else
+				{
+					deh_strlcpy(mapheaderinfo[num]->positionmus, word2,
+						sizeof(mapheaderinfo[num]->positionmus), va("Level header %d: POSITION!! music", num));
+				}
+			}
 			else if (fastcmp(word, "MUSICTRACK"))
 				mapheaderinfo[num]->mustrack = ((UINT16)i - 1);
 			else if (fastcmp(word, "MUSICPOS"))

src/doomstat.h

@@ -445,8 +445,9 @@ struct mapheader_t
 
 	// Music information
 	char musname[MAXMUSNAMES][7];		///< Music tracks to play. First dimension is the track number, second is the music string. "" for no music.
-	UINT8 musname_size;					///< Number of music tracks defined
 	char associatedmus[MAXMUSNAMES][7];	///< Associated music tracks for sound test unlock.
+	char positionmus[7];				///< Custom Position track. Doesn't play in Encore or other fun game-controlled contexts
+	UINT8 musname_size;					///< Number of music tracks defined
 	UINT8 associatedmus_size;			///< Number of associated music tracks defined
 	UINT16 mustrack;					///< Subsong to play. Only really relevant for music modules and specific formats supported by GME. 0 to ignore.
 	UINT32 muspos;						///< Music position to jump to.

src/p_tick.c

@@ -801,7 +801,11 @@ void P_Ticker(boolean run)
 			{
 				// Plays the POSITION music after the camera spin
 				if (leveltime == introtime)
-					S_ChangeMusicInternal("postn", true);
+					S_ChangeMusicInternal(
+						(mapheaderinfo[gamemap-1]->positionmus[0]
+							? mapheaderinfo[gamemap-1]->positionmus
+							: "postn"
+						), true);
 			}
 		}
 

src/s_sound.c

@@ -1391,6 +1391,11 @@ static void S_InsertMapIntoSoundTestSequence(UINT16 map, musicdef_t ***tail)
 {
 	UINT8 i;
 
+	if (mapheaderinfo[map]->positionmus[0])
+	{
+		S_InsertMusicAtSoundTestSequenceTail(mapheaderinfo[map]->positionmus, map, tail);
+	}
+
 	for (i = 0; i < mapheaderinfo[map]->musname_size; i++)
 	{
 		S_InsertMusicAtSoundTestSequenceTail(mapheaderinfo[map]->musname[i], map, tail);