From dd1715aa15838493bef505df575d9943aabb84f1 Mon Sep 17 00:00:00 2001
From: James R <justsomejames2@gmail.com>
Date: Fri, 29 Nov 2019 17:23:40 -0800
Subject: [PATCH] Optionally only resync Invincibility and Grow music

---
 src/i_sound.h         |  1 +
 src/p_user.c          |  2 ++
 src/s_sound.c         | 22 ++++++++++++++++++++++
 src/s_sound.h         |  9 +++++++++
 src/sdl/mixer_sound.c | 13 ++++++++++++-
 5 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/src/i_sound.h b/src/i_sound.h
index 422cfb8ff..93e3f6dd0 100644
--- a/src/i_sound.h
+++ b/src/i_sound.h
@@ -159,6 +159,7 @@ boolean I_SetSongPosition(UINT32 position);
 UINT32 I_GetSongPosition(void);
 
 void I_UpdateSongLagThreshold (void);
+void I_UpdateSongLagConditions (void);
 
 /// ------------------------
 //  MUSIC PLAYBACK
diff --git a/src/p_user.c b/src/p_user.c
index 5fee0ac9b..6af902dc2 100644
--- a/src/p_user.c
+++ b/src/p_user.c
@@ -1248,12 +1248,14 @@ void P_RestoreMusic(player_t *player)
 		if (wantedmus == 2)
 		{
 			S_ChangeMusicInternal("kgrow", true);
+			S_SetMusicUsage(MUS_SPECIAL);
 			S_SetRestoreMusicFadeInCvar(&cv_growmusicfade);
 		}
 		// Item - Invincibility
 		else if (wantedmus == 1)
 		{
 			S_ChangeMusicInternal("kinvnc", true);
+			S_SetMusicUsage(MUS_SPECIAL);
 			S_SetRestoreMusicFadeInCvar(&cv_invincmusicfade);
 		}
 		else
diff --git a/src/s_sound.c b/src/s_sound.c
index 3cb5ef7fe..4e26a1d7b 100644
--- a/src/s_sound.c
+++ b/src/s_sound.c
@@ -130,6 +130,10 @@ consvar_t cv_music_resync_threshold = {
 	"music_resync_threshold", "100", CV_SAVE|CV_CALL,
 	music_resync_threshold_cons_t, I_UpdateSongLagThreshold
 };
+consvar_t cv_music_resync_powerups_only = {
+	"music_resync_powerups_only", "No", CV_SAVE|CV_CALL,
+	CV_YesNo, I_UpdateSongLagConditions
+};
 
 #define S_MAX_VOLUME 127
 
@@ -295,6 +299,7 @@ void S_RegisterSoundStuff(void)
 	CV_RegisterVar(&cv_playsoundifunfocused);
 
 	CV_RegisterVar(&cv_music_resync_threshold);
+	CV_RegisterVar(&cv_music_resync_powerups_only);
 
 	COM_AddCommand("tunes", Command_Tunes_f);
 	COM_AddCommand("restartaudio", Command_RestartAudio_f);
@@ -1564,6 +1569,7 @@ static void      *music_data;
 static UINT16    music_flags;
 static boolean   music_looping;
 static consvar_t *music_refade_cv;
+static int       music_usage;
 
 static char      queue_name[7];
 static UINT16    queue_flags;
@@ -1949,6 +1955,7 @@ static void S_UnloadMusic(void)
 	music_looping = false;
 
 	music_refade_cv = 0;
+	music_usage = 0;
 }
 
 static boolean S_PlayMusic(boolean looping, UINT32 fadeinms)
@@ -1956,6 +1963,8 @@ static boolean S_PlayMusic(boolean looping, UINT32 fadeinms)
 	if (S_MusicDisabled())
 		return false;
 
+	I_UpdateSongLagConditions();
+
 	if ((!fadeinms && !I_PlaySong(looping)) ||
 		(fadeinms && !I_FadeInPlaySong(fadeinms, looping)))
 	{
@@ -2188,6 +2197,19 @@ S_GetRestoreMusicFadeIn (void)
 		return 0;
 }
 
+void
+S_SetMusicUsage (int type)
+{
+	music_usage = type;
+	I_UpdateSongLagConditions();
+}
+
+int
+S_MusicUsage (void)
+{
+	return music_usage;
+}
+
 /// ------------------------
 /// Music Fading
 /// ------------------------
diff --git a/src/s_sound.h b/src/s_sound.h
index 8e94f8e16..5c173138e 100644
--- a/src/s_sound.h
+++ b/src/s_sound.h
@@ -37,6 +37,7 @@ extern consvar_t cv_playmusicifunfocused;
 extern consvar_t cv_playsoundifunfocused;
 
 extern consvar_t cv_music_resync_threshold;
+extern consvar_t cv_music_resync_powerups_only;
 
 #ifdef SNDSERV
 extern consvar_t sndserver_cmd, sndserver_arg;
@@ -178,6 +179,11 @@ UINT32 S_GetMusicPosition(void);
 // Music Playback
 //
 
+enum
+{
+	MUS_SPECIAL = 1,/* powerups--invincibility, grow */
+};
+
 // Start music track, arbitrary, given its name, and set whether looping
 // note: music flags 12 bits for tracknum (gme, other formats with more than one track)
 //       13-15 aren't used yet
@@ -191,6 +197,9 @@ void S_SetRestoreMusicFadeInCvar (consvar_t *cvar);
 	S_SetRestoreMusicFadeInCvar(0)
 int  S_GetRestoreMusicFadeIn (void);
 
+void S_SetMusicUsage (int type);
+int  S_MusicUsage (void);
+
 // Stops the music.
 void S_StopMusic(void);
 
diff --git a/src/sdl/mixer_sound.c b/src/sdl/mixer_sound.c
index 52610575e..77fcc0914 100644
--- a/src/sdl/mixer_sound.c
+++ b/src/sdl/mixer_sound.c
@@ -80,6 +80,7 @@ write netcode into the sound code, OKAY?
 
 UINT8 sound_started = false;
 
+static UINT32 stutter_threshold_user;
 static UINT32 stutter_threshold;
 
 static Mix_Music *music;
@@ -942,7 +943,17 @@ UINT32 I_GetSongPosition(void)
 void
 I_UpdateSongLagThreshold (void)
 {
-	stutter_threshold = cv_music_resync_threshold.value/1000.0*(4*44100);
+	stutter_threshold_user = cv_music_resync_threshold.value/1000.0*(4*44100);
+	I_UpdateSongLagConditions();
+}
+
+void
+I_UpdateSongLagConditions (void)
+{
+	if (! cv_music_resync_powerups_only.value || S_MusicUsage() == MUS_SPECIAL)
+		stutter_threshold = stutter_threshold_user;
+	else
+		stutter_threshold = 0;
 }
 
 /// ------------------------