Tracks can be mapped to multiple channels.

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+(Breaking Change) Track mappings now support mapping to multiple channels.
+
 ## [0.1.3] - MIDI tuning, accuracy.
 
 MIDI playback is now more accurate and has been tuned to be more in time with audio

src/audio.rs

@@ -27,7 +27,7 @@ pub trait Device: fmt::Display + std::marker::Send + std::marker::Sync {
     fn play(
         &self,
         song: Arc<Song>,
-        mappings: &HashMap<String, u16>,
+        mappings: &HashMap<String, Vec<u16>>,
         cancel_handle: CancelHandle,
         play_barrier: Arc<Barrier>,
     ) -> Result<(), Box<dyn Error>>;

src/audio/cpal.rs

@@ -117,7 +117,7 @@
     fn play(
         &self,
         song: Arc<Song>,
-        mappings: &HashMap<String, u16>,
+        mappings: &HashMap<String, Vec<u16>>,
         cancel_handle: CancelHandle,
         play_barrier: Arc<Barrier>,
     ) -> Result<(), Box<dyn Error>> {
@@ -137,7 +137,7 @@
     fn play_format<S>(
         &self,
         song: Arc<Song>,
-        mappings: &HashMap<String, u16>,
+        mappings: &HashMap<String, Vec<u16>>,
         cancel_handle: CancelHandle,
         play_barrier: Arc<Barrier>,
     ) -> Result<(), Box<dyn Error>>
@@ -167,6 +167,7 @@
         let num_channels = *mappings
             .iter()
             .map(|entry| entry.1)
+            .flatten()
             .max()
             .ok_or("no max channel found")?;
 
@@ -282,9 +283,9 @@
         let track2 = Track::new("test 2".into(), tempwav2_path, Some(1))?;
 
         let song = Song::new("song name".into(), None, None, vec![track1, track2])?;
-        let mut mappings: HashMap<String, u16> = HashMap::new();
-        mappings.insert("test 1".into(), 1);
-        mappings.insert("test 2".into(), 4);
+        let mut mappings: HashMap<String, Vec<u16>> = HashMap::new();
+        mappings.insert("test 1".into(), vec![1]);
+        mappings.insert("test 2".into(), vec![4]);
 
         let source = song.source::<i32>(&mappings)?;
         let (tx, rx) = channel();
@@ -324,9 +325,9 @@
         let track2 = Track::new("test 2".into(), tempwav2_path, Some(1))?;
 
         let song = Song::new("song name".into(), None, None, vec![track1, track2])?;
-        let mut mappings: HashMap<String, u16> = HashMap::new();
-        mappings.insert("test 1".into(), 1);
-        mappings.insert("test 2".into(), 4);
+        let mut mappings: HashMap<String, Vec<u16>> = HashMap::new();
+        mappings.insert("test 1".into(), vec![1]);
+        mappings.insert("test 2".into(), vec![4]);
 
         let source = song.source::<i32>(&mappings)?;
         let (tx, rx) = channel();
@@ -359,9 +360,9 @@
         let track2 = Track::new("test 2".into(), tempwav2_path, Some(1))?;
 
         let song = Song::new("song name".into(), None, None, vec![track1, track2])?;
-        let mut mappings: HashMap<String, u16> = HashMap::new();
-        mappings.insert("test 1".into(), 1);
-        mappings.insert("test 2".into(), 4);
+        let mut mappings: HashMap<String, Vec<u16>> = HashMap::new();
+        mappings.insert("test 1".into(), vec![1]);
+        mappings.insert("test 2".into(), vec![4]);
 
         let source = song.source::<i32>(&mappings)?;
         let (tx, rx) = channel();

src/audio/mock.rs

@@ -53,7 +53,7 @@ impl super::Device for Device {
     fn play(
         &self,
         song: Arc<Song>,
-        _: &HashMap<String, u16>,
+        _: &HashMap<String, Vec<u16>>,
         cancel_handle: CancelHandle,
         play_barrier: Arc<Barrier>,
     ) -> Result<(), Box<dyn Error>> {

src/config/trackmappings.rs

@@ -20,5 +20,5 @@ use serde::Deserialize;
 pub(super) struct TrackMappings {
     // The individual track mappings.
     #[serde(flatten)]
-    pub track_mappings: HashMap<String, u16>,
+    pub track_mappings: HashMap<String, Vec<u16>>,
 }

src/controller.rs

@@ -221,7 +221,7 @@ mod test {
     #[tokio::test(flavor = "multi_thread")]
     async fn test_controller() -> Result<(), Box<dyn Error>> {
         let driver = Arc::new(TestDriver::new(TestEvent::Unset));
-        let mappings: HashMap<String, u16> = HashMap::new();
+        let mappings: HashMap<String, Vec<u16>> = HashMap::new();
         let device = Arc::new(audio::test::Device::get("mock-device"));
         let songs = config::get_all_songs(&PathBuf::from("assets/songs"))?;
         let playlist =

src/controller/midi.rs

@@ -208,7 +208,7 @@ mod test {
         playlist_event.write(&mut playlist_buf)?;
 
         let device = Arc::new(audio::test::Device::get("mock-device"));
-        let mappings: HashMap<String, u16> = HashMap::new();
+        let mappings: HashMap<String, Vec<u16>> = HashMap::new();
         let songs = config::get_all_songs(&PathBuf::from("assets/songs"))?;
         let playlist =
             config::parse_playlist(&PathBuf::from("assets/playlist.yaml"), songs.clone())?;

src/main.rs

@@ -173,15 +173,21 @@
             repository_path,
             song_name,
         } => {
-            let mut converted_mappings: HashMap<String, u16> = HashMap::new();
+            let mut converted_mappings: HashMap<String, Vec<u16>> = HashMap::new();
             for mapping in mappings.split(',') {
                 let track_and_channel: Vec<&str> = mapping.split('=').collect();
                 if track_and_channel.len() != 2 {
                     return Err("malformed track to channel mapping".into());
                 };
                 let track = track_and_channel[0];
                 let channel = track_and_channel[1].parse::<u16>()?;
-                converted_mappings.insert(track.into(), channel);
+                if !converted_mappings.contains_key(track.into()) {
+                    converted_mappings.insert(track.into(), vec![]);
+                }
+                converted_mappings
+                    .get_mut(track.into())
+                    .expect("expected mapping")
+                    .push(channel);
             }
 
             let device = audio::get_device(&device_name)?;

src/player.rs

@@ -39,7 +39,7 @@ pub struct Player {
     /// The device to play audio through.
     device: Arc<dyn audio::Device>,
     /// Mappings of tracks to output channels.
-    mappings: Arc<HashMap<String, u16>>,
+    mappings: Arc<HashMap<String, Vec<u16>>>,
     /// The MIDI device to play MIDI back through.
     midi_device: Option<Arc<dyn midi::Device>>,
     /// The playlist to use.
@@ -61,7 +61,7 @@ impl Player {
     /// Creates a new player.
     pub fn new(
         device: Arc<dyn audio::Device>,
-        mappings: HashMap<String, u16>,
+        mappings: HashMap<String, Vec<u16>>,
         midi_device: Option<Arc<dyn midi::Device>>,
         playlist: Arc<Playlist>,
         all_songs_playlist: Arc<Playlist>,
@@ -154,7 +154,7 @@ impl Player {
 
     fn play_files(
         device: Arc<dyn audio::Device>,
-        mappings: Arc<HashMap<String, u16>>,
+        mappings: Arc<HashMap<String, Vec<u16>>>,
         midi_device: Option<Arc<dyn midi::Device>>,
         song: Arc<Song>,
         cancel_handle: CancelHandle,
@@ -390,7 +390,7 @@ mod test {
     #[tokio::test(flavor = "multi_thread")]
     async fn test_player() -> Result<(), Box<dyn Error>> {
         let device = Arc::new(audio::test::Device::get("mock-device"));
-        let mappings: HashMap<String, u16> = HashMap::new();
+        let mappings: HashMap<String, Vec<u16>> = HashMap::new();
         let midi_device = Arc::new(midi::test::Device::get("mock-midi-device"));
         let songs = config::get_all_songs(&PathBuf::from("assets/songs"))?;
         let playlist =

src/songs.rs

@@ -171,7 +171,7 @@
     /// Returns a rodio source for the song.
     pub fn source<S>(
         &self,
-        track_mappings: &HashMap<String, u16>,
+        track_mappings: &HashMap<String, Vec<u16>>,
     ) -> Result<SongSource<S>, Box<dyn Error>>
     where
         S: Sample,
@@ -298,7 +298,7 @@
 {
     fn new(
         song: &Song,
-        track_mapping: &HashMap<String, u16>,
+        track_mapping: &HashMap<String, Vec<u16>>,
     ) -> Result<SongSource<S>, Box<dyn Error>> {
         let mut files_to_tracks = HashMap::<PathBuf, Vec<&Track>>::new();
 
@@ -317,6 +317,7 @@
         let num_channels = *track_mapping
             .iter()
             .map(|entry| entry.1)
+            .flatten()
             .max()
             .ok_or("no max channel found")?;
 
@@ -334,12 +335,14 @@
             let mut file_channel_to_output_channels: HashMap<u16, Vec<usize>> = HashMap::new();
             tracks.into_iter().for_each(|track| {
                 let file_channel = track.file_channel - 1;
-                if let Some(channel_mapping) = track_mapping.get(&track.name.to_string()) {
-                    let output_channel = channel_mapping - 1;
-                    file_channel_to_output_channels
-                        .entry(file_channel)
-                        .or_default()
-                        .push(output_channel.into());
+                if let Some(channel_mappings) = track_mapping.get(&track.name.to_string()) {
+                    channel_mappings.into_iter().for_each(|channel_mapping| {
+                        let output_channel = channel_mapping - 1;
+                        file_channel_to_output_channels
+                            .entry(file_channel)
+                            .or_default()
+                            .push(output_channel.into());
+                    })
                 }
             });
 
@@ -676,10 +679,10 @@
         let track3 = super::Track::new("test 3".into(), tempwav3_path, Some(1))?;
 
         let song = super::Song::new("song name".into(), None, None, vec![track1, track2, track3])?;
-        let mut mapping: HashMap<String, u16> = HashMap::new();
-        mapping.insert("test 1".into(), 1);
-        mapping.insert("test 2".into(), 4);
-        mapping.insert("test 3".into(), 4);
+        let mut mapping: HashMap<String, Vec<u16>> = HashMap::new();
+        mapping.insert("test 1".into(), vec![1]);
+        mapping.insert("test 2".into(), vec![4]);
+        mapping.insert("test 3".into(), vec![4]);
 
         song.source(&mapping)
     }