Fix ambient sound not updating in game on setting options change

src/options.cpp

@@ -3331,7 +3331,7 @@ bool options_manager::save()
 {
     const auto savefile = PATH_INFO::options();
     cache_to_globals();
-    update_music_volume();
+    update_volumes();
 
     return write_to_file( savefile, [&]( std::ostream & fout ) {
         JsonOut jout( fout, true );

src/sdlsound.cpp

@@ -77,6 +77,18 @@ static bool sound_init_success = false;
 static std::map<std::string, music_playlist> playlists;
 static std::string current_soundpack_path;
 
+/** The ambient sound we're currently playing **/
+struct ambient_parameters {
+    std::string id;
+    std::string variant;
+    int volume;
+    sfx::channel channel;
+    int fade_in_duration;
+    double pitch;
+    int loops;
+};
+static ambient_parameters current_ambient;
+
 static std::unordered_map<std::string, int> unique_paths;
 static sfx_resources_t sfx_resources;
 static std::vector<id_and_variant> sfx_preload;
@@ -270,7 +282,7 @@ void stop_music()
     absolute_playlist_at = 0;
 }
 
-void update_music_volume()
+void update_volumes()
 {
     if( test_mode ) {
         return;
@@ -281,14 +293,33 @@ void update_music_volume()
         return;
     }
 
+    // Change volume of current music
     Mix_VolumeMusic( current_music_track_volume * get_option<int>( "MUSIC_VOLUME" ) / 100 );
+
+
     // Start playing music, if we aren't already doing so (if
     // SOUND_ENABLED was toggled.)
 
     // needs to be changed to something other than a static string when
     // #28018 is resolved, as this function may be called from places
     // other than the main menu.
     play_music( "title" );
+
+
+    // Stop channels playing (different ambient sounds)
+    // Then start back the last saved ambient sound with the new volume (fetched in the function)
+    if( !current_ambient.id.empty() ) {
+        // Stop currently playing channels
+        for( int i = 0; i < static_cast<int>( sfx::channel::MAX_CHANNEL ); i++ ) {
+            if( sfx::is_channel_playing( static_cast<sfx::channel>( i ) ) ) {
+                Mix_HaltChannel( i );
+            }
+        }
+        // Start the last playing channel with updated volume
+        sfx::play_ambient_variant_sound( current_ambient.id, current_ambient.variant,
+                                         current_ambient.volume, current_ambient.channel, current_ambient.fade_in_duration,
+                                         current_ambient.pitch, current_ambient.loops );
+    }
 }
 
 // Allocate new Mix_Chunk as a null-chunk. Results in a valid, but empty chunk
@@ -605,6 +636,13 @@ void sfx::play_ambient_variant_sound( const std::string &id, const std::string &
             cleanup_when_channel_finished( ch, effect_to_play );
         }
     }
+    current_ambient.id = id;
+    current_ambient.variant = variant;
+    current_ambient.volume = volume;
+    current_ambient.channel = channel;
+    current_ambient.fade_in_duration = fade_in_duration;
+    current_ambient.pitch = pitch;
+    current_ambient.loops = loops;
 }
 
 void load_soundset()

src/sdlsound.h

@@ -12,7 +12,7 @@ bool init_sound();
 void shutdown_sound();
 void play_music( const std::string &playlist );
 void stop_music();
-void update_music_volume();
+void update_volumes();
 void load_soundset();
 
 #else
@@ -25,7 +25,7 @@ inline void shutdown_sound() { }
 inline void play_music( const std::string &/*playlist*/ )
 {
 }
-inline void update_music_volume() { }
+inline void update_volumes() { }
 inline void load_soundset() { }
 
 #endif