music: add ability to mute music in main menu

Closes #119

cfg/Tomb1Main.json5

@@ -146,6 +146,9 @@
     // Disables ingame cinematics.
     "disable_cine": false,
 
+    // Disables music in the main menu.
+    "disable_music_in_menu": false,
+
     // Overrides game resolution. Leave at 0 or negative values to
     // automatically guess from the screen size. Note: these values
     // only override the last position in the game resolutions menu that

src/config.c

@@ -149,6 +149,7 @@ int8_t T1MReadConfigFromJson(const char *cfg_data)
     READ_BOOL(disable_demo, 0);
     READ_BOOL(disable_fmv, 0);
     READ_BOOL(disable_cine, 0);
+    READ_BOOL(disable_music_in_menu, 0);
 
     READ_BAR_SHOWING_MODE(healthbar_showing_mode, T1M_BSM_FLASHING_OR_DEFAULT);
     READ_BAR_SHOWING_MODE(airbar_showing_mode, T1M_BSM_DEFAULT);

src/config.h

@@ -64,6 +64,7 @@ typedef struct {
     int8_t disable_demo;
     int8_t disable_fmv;
     int8_t disable_cine;
+    int8_t disable_music_in_menu;
     int32_t resolution_width;
     int32_t resolution_height;
 } T1MConfigStruct;

src/specific/sndpc.c

@@ -358,6 +358,10 @@ void S_MusicUnpause()
 // original name: CDPlay
 int32_t MusicPlay(int16_t track)
 {
+    if (CurrentLevel == GF.title_level_num && T1MConfig.disable_music_in_menu) {
+        return 0;
+    }
+
     if (track < 2) {
         return 0;
     }