initial organya implementation

Cargo.toml

@@ -16,6 +16,7 @@ approx = "0.3"
 bitflags = "1"
 bitvec = "0.17.4"
 byteorder = "1.3"
+cpal = "0.12.1"
 directories = "2"
 gfx = "0.18"
 gfx_core = "0.9"

src/builtin_fs.rs

@@ -110,6 +110,7 @@ impl BuiltinFS {
                     FSNode::File("builtin_font.fnt", include_bytes!("builtin/builtin_font.fnt")),
                     FSNode::File("builtin_font_0.png", include_bytes!("builtin/builtin_font_0.png")),
                     FSNode::File("builtin_font_1.png", include_bytes!("builtin/builtin_font_1.png")),
+                    FSNode::File("pixtone.pcm", include_bytes!("builtin/pixtone.pcm")),
                 ])
             ],
         }

src/ggez/error.rs

@@ -4,7 +4,7 @@
 use std::error::Error;
 use std::fmt;
 use std::string::FromUtf8Error;
-use std::sync::Arc;
+use std::sync::{Arc, PoisonError};
 
 /// An enum containing all kinds of game framework errors.
 #[derive(Debug, Clone)]
@@ -232,3 +232,31 @@ impl From<strum::ParseError> for GameError {
         GameError::ParseError(errstr)
     }
 }
+
+impl From<cpal::DefaultStreamConfigError> for GameError {
+    fn from(s: cpal::DefaultStreamConfigError) -> GameError {
+        let errstr = format!("Default stream config error: {}", s);
+        GameError::AudioError(errstr)
+    }
+}
+
+impl From<cpal::PlayStreamError> for GameError {
+    fn from(s: cpal::PlayStreamError) -> GameError {
+        let errstr = format!("Play stream error: {}", s);
+        GameError::AudioError(errstr)
+    }
+}
+
+impl From<cpal::BuildStreamError> for GameError {
+    fn from(s: cpal::BuildStreamError) -> GameError {
+        let errstr = format!("Build stream error: {}", s);
+        GameError::AudioError(errstr)
+    }
+}
+
+impl<T> From<PoisonError<T>> for GameError {
+    fn from(s: PoisonError<T>) -> GameError {
+        let errstr = format!("Poison error: {}", s);
+        GameError::EventLoopError(errstr)
+    }
+}

src/main.rs

@@ -187,7 +187,7 @@ impl Game {
                 texture_set: TextureSet::new(base_path),
                 base_path: str!(base_path),
                 stages: Vec::with_capacity(96),
-                sound_manager: SoundManager::new(ctx),
+                sound_manager: SoundManager::new(ctx)?,
                 constants,
                 scale,
                 screen_size,

src/sound/mod.rs

@@ -1,33 +1,204 @@
-use crate::ggez::{Context, GameResult};
+use std::sync::{mpsc, RwLock};
+use std::sync::mpsc::{Receiver, Sender};
+
+use bitflags::_core::time::Duration;
+use cpal::Sample;
+use cpal::traits::{DeviceTrait, HostTrait, StreamTrait};
+
+use crate::engine_constants::EngineConstants;
+use crate::ggez::{Context, filesystem, GameResult};
+use crate::ggez::GameError::AudioError;
+use crate::sound::organya::Song;
+use crate::sound::playback::PlaybackEngine;
+use crate::sound::wave_bank::SoundBank;
+use crate::str;
 
 pub mod pixtone;
+mod wave_bank;
+mod organya;
+mod playback;
+mod stuff;
+mod wav;
 
 pub struct SoundManager {
-    intro: Vec<u8>,
-    sloop: Vec<u8>,
+    tx: Sender<PlaybackMessage>,
+    current_song_id: usize,
 }
 
-//unsafe impl Send for SoundManager {}
+static SONGS: [&'static str; 42] = [
+    "XXXX",
+    "WANPAKU",
+    "ANZEN",
+    "GAMEOVER",
+    "GRAVITY",
+    "WEED",
+    "MDOWN2",
+    "FIREEYE",
+    "VIVI",
+    "MURA",
+    "FANFALE1",
+    "GINSUKE",
+    "CEMETERY",
+    "PLANT",
+    "KODOU",
+    "FANFALE3",
+    "FANFALE2",
+    "DR",
+    "ESCAPE",
+    "JENKA",
+    "MAZE",
+    "ACCESS",
+    "IRONH",
+    "GRAND",
+    "Curly",
+    "OSIDE",
+    "REQUIEM",
+    "WANPAK2",
+    "QUIET",
+    "LASTCAVE",
+    "BALCONY",
+    "LASTBTL",
+    "LASTBT3",
+    "ENDING",
+    "ZONBIE",
+    "BDOWN",
+    "HELL",
+    "JENKA2",
+    "MARINE",
+    "BALLOS",
+    "TOROKO",
+    "WHITE"
+];
 
 impl SoundManager {
-    pub fn new(ctx: &mut Context) -> SoundManager {
-        SoundManager {
-            intro: Vec::new(),
-            sloop: Vec::new(),
-        }
+    pub fn new(ctx: &mut Context) -> GameResult<SoundManager> {
+        let (tx, rx): (Sender<PlaybackMessage>, Receiver<PlaybackMessage>) = mpsc::channel();
+
+        let host = cpal::default_host();
+        let device = host.default_output_device().ok_or_else(|| AudioError(str!("Error initializing audio device.")))?;
+        let config = device.default_output_config()?;
+
+        let bnk = wave_bank::SoundBank::load_from(filesystem::open(ctx, "/builtin/pixtone.pcm")?)?;
+
+        std::thread::spawn(move || {
+            if let Err(err) = match config.sample_format() {
+                cpal::SampleFormat::F32 => run::<f32>(rx, bnk, &device, &config.into()),
+                cpal::SampleFormat::I16 => run::<i16>(rx, bnk, &device, &config.into()),
+                cpal::SampleFormat::U16 => run::<u16>(rx, bnk, &device, &config.into()),
+            } {
+                log::error!("Something went wrong in audio thread: {}", err);
+            }
+        });
+
+        Ok(SoundManager {
+            tx: tx.clone(),
+            current_song_id: 0,
+        })
     }
 
-    pub fn play_song(&mut self, ctx: &mut Context) -> GameResult {
-        /*self.intro.clear();
-        self.sloop.clear();
-        ggez::filesystem::open(ctx, "/base/Ogg11/curly_intro.ogg")?.read_to_end(&mut self.intro)?;
-        ggez::filesystem::open(ctx, "/base/Ogg11/curly_loop.ogg")?.read_to_end(&mut self.sloop)?;
+    pub fn play_song(&mut self, song_id: usize, constants: &EngineConstants, ctx: &mut Context) -> GameResult {
+        if self.current_song_id == song_id {
+            return Ok(());
+        }
 
-        let sink = Sink::new(ctx.audio_context.device());
-        sink.append(rodio::Decoder::new(Cursor::new(self.intro.clone()))?);
-        sink.append(rodio::Decoder::new(Cursor::new(self.sloop.clone()))?);
-        sink.detach();*/
+        if let Some(song_name) = SONGS.get(song_id) {
+            let org = organya::Song::load_from(filesystem::open(ctx, ["/base/Org/", &song_name.to_lowercase(), ".org"].join(""))?)?;
+            log::info!("Playing song: {}", song_name);
 
+            self.current_song_id = song_id;
+            self.tx.send(PlaybackMessage::PlaySong(org));
+        }
         Ok(())
     }
 }
+
+enum PlaybackMessage {
+    Stop,
+    PlaySong(Song),
+}
+
+#[derive(PartialEq, Eq)]
+enum PlaybackState {
+    Stopped,
+    Playing,
+}
+
+fn run<T>(rx: Receiver<PlaybackMessage>, bank: SoundBank,
+          device: &cpal::Device, config: &cpal::StreamConfig) -> GameResult where
+    T: cpal::Sample,
+{
+    let sample_rate = config.sample_rate.0 as f32;
+    let channels = config.channels as usize;
+    let mut state = PlaybackState::Stopped;
+    let mut new_song: Option<Song> = None;
+    let mut engine = PlaybackEngine::new(Song::empty(), &bank);
+
+    log::info!("Audio format: {} {}", sample_rate, channels);
+    engine.set_sample_rate(sample_rate as usize);
+    engine.loops = usize::MAX;
+
+    let mut buf = vec![0x8080; 441];
+    let mut index = 0;
+    let mut frames = engine.render_to(&mut buf);
+
+    let err_fn = |err| eprintln!("an error occurred on stream: {}", err);
+
+    let stream = device.build_output_stream(
+        config,
+        move |data: &mut [T], _: &cpal::OutputCallbackInfo| {
+            match rx.try_recv() {
+                Ok(PlaybackMessage::PlaySong(song)) => {
+                    engine.start_song(song, &bank);
+
+                    for i in &mut buf[0..frames] { *i = 0x8080 };
+                    frames = engine.render_to(&mut buf);
+                    index = 0;
+
+                    state = PlaybackState::Playing;
+                }
+                _ => {}
+            }
+
+            for frame in data.chunks_mut(channels) {
+                let sample: u16 = {
+                    if state == PlaybackState::Stopped {
+                        0x8000
+                    } else if index < frames {
+                        let sample = buf[index];
+                        index += 1;
+                        if index & 1 == 0 { (sample & 0xff) << 8 } else { sample & 0xff00 }
+                    } else {
+                        for i in &mut buf[0..frames] { *i = 0x8080 };
+                        frames = engine.render_to(&mut buf);
+                        index = 0;
+                        let sample = buf[0];
+                        (sample & 0xff) << 8
+                    }
+                };
+
+                let value: T = cpal::Sample::from::<u16>(&sample);
+                for sample in frame.iter_mut() {
+                    *sample = value;
+                }
+            }
+        },
+        err_fn,
+    )?;
+    stream.play()?;
+
+    loop {
+        std::thread::sleep(Duration::from_millis(10));
+    }
+}
+
+fn write_data<T>(output: &mut [T], channels: usize, next_sample: &mut dyn FnMut() -> u16)
+    where
+        T: cpal::Sample,
+{
+    for frame in output.chunks_mut(channels) {
+        let value: T = cpal::Sample::from::<u16>(&next_sample());
+        for sample in frame.iter_mut() {
+            *sample = value;
+        }
+    }
+}

src/sound/organya.rs

@@ -0,0 +1,225 @@
+#[repr(u8)]
+#[derive(Debug, Copy, Clone)]
+pub enum Version {
+    // Can't find any files with this signature,
+    // But apparently these files had no Pi flag.
+    Beta = b'1',
+    Main = b'2',
+    // OrgMaker 2.05 Extended Drums
+    Extended = b'3'
+}
+
+#[derive(Debug, Copy, Clone)]
+pub struct LoopRange {
+    // inclusive
+    pub start: i32,
+    // exclusive
+    pub end: i32
+}
+
+#[derive(Debug, Copy, Clone)]
+pub struct Display {
+    pub beats: u8,
+    pub steps: u8
+}
+
+#[derive(Debug, Copy, Clone)]
+pub struct Timing {
+    pub wait: u16,
+    pub loop_range: LoopRange
+}
+
+#[derive(Copy, Clone)]
+#[derive(Debug)]
+pub struct Instrument {
+    pub freq: u16,
+    pub inst: u8,
+    pub pipi: u8,
+    pub notes: u16
+}
+
+pub struct Track {
+    pub inst: Instrument,
+    pub notes: Vec<Note>
+}
+
+impl Clone for Track {
+    fn clone(&self) -> Track {
+        Track {
+            inst: self.inst,
+            notes: self.notes.clone(),
+        }
+    }
+}
+
+impl std::fmt::Debug for Track {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        self.inst.fmt(f)
+    }
+}
+
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct Note {
+    pub pos: i32,
+    pub key: u8,
+    pub len: u8,
+    pub vol: u8,
+    pub pan: u8
+}
+
+#[derive(Debug)]
+pub struct Song {
+    pub version: Version,
+    pub time: Timing,
+    pub tracks: [Track; 16]
+}
+
+impl Clone for Song {
+    fn clone(&self) -> Song {
+        Song {
+            version: self.version,
+            time: self.time,
+            tracks: self.tracks.clone(),
+        }
+    }
+}
+
+use byteorder::{LE, ReadBytesExt};
+use std::io;
+
+impl Song {
+    pub fn empty() -> Song {
+        Song {
+            version: Version::Main,
+            time: Timing { wait: 8, loop_range: LoopRange { start: 0, end: 1 } },
+            tracks: [
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+                Track { inst: Instrument {freq: 1000, inst: 0, pipi: 0, notes: 0}, notes: vec![] },
+            ]
+        }
+    }
+
+    pub fn load_from<R: io::Read>(mut f: R) -> io::Result<Song> {
+        let mut magic = [0; 6];
+        
+        f.read_exact(&mut magic)?;
+        
+        let version = 
+            match &magic {
+                b"Org-01" => Version::Beta,
+                b"Org-02" => Version::Main,
+                b"Org-03" => Version::Extended,
+                _         => return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid magic number"))
+            };
+        
+        let wait  = f.read_u16::<LE>()?;
+        let _bpm  = f.read_u8()?;
+        let _spb  = f.read_u8()?;
+        let start = f.read_i32::<LE>()?;
+        let end   = f.read_i32::<LE>()?;
+        
+        use std::mem::MaybeUninit as Mu;
+        
+        let mut insts: [Mu<Instrument>; 16] = unsafe {
+            Mu::uninit().assume_init()
+        };
+        
+        for i in insts.iter_mut() {
+            let freq  = f.read_u16::<LE>()?;
+            let inst  = f.read_u8()?;
+            let pipi  = f.read_u8()?;
+            let notes = f.read_u16::<LE>()?;
+            
+            *i = Mu::new(Instrument {
+                freq,
+                inst,
+                pipi,
+                notes
+            });
+        }
+        
+        let insts: [Instrument; 16] = unsafe {
+            std::mem::transmute(insts)
+        };
+        
+        let mut tracks: [Mu<Track>; 16] = unsafe {
+            Mu::uninit().assume_init()
+        };
+        
+        for (i, t) in tracks.iter_mut().enumerate() {
+            let count = insts[i].notes as usize;
+            
+            #[repr(C)]
+            #[derive(Copy, Clone)]
+            struct UninitNote {
+                pos: Mu<i32>,
+                key: Mu<u8>,
+                len: Mu<u8>,
+                vol: Mu<u8>,
+                pan: Mu<u8>
+            }
+            
+            let mut notes: Vec<UninitNote> = unsafe {
+                vec![Mu::uninit().assume_init(); count]
+            };
+                
+            for note in notes.iter_mut() {
+                note.pos = Mu::new(f.read_i32::<LE>()?);
+            }
+            
+            for note in notes.iter_mut() {
+                note.key = Mu::new(f.read_u8()?);
+            }
+            
+            for note in notes.iter_mut() {
+                note.len = Mu::new(f.read_u8()?);
+            }
+            
+            for note in notes.iter_mut() {
+                note.vol = Mu::new(f.read_u8()?);
+            }
+            
+            for note in notes.iter_mut() {
+                note.pan = Mu::new(f.read_u8()?);
+            }
+            
+            *t = Mu::new(Track {
+                inst: insts[i],
+                notes: unsafe { std::mem::transmute(notes) }
+            });
+        }
+        
+        let tracks = unsafe {
+            std::mem::transmute(tracks)
+        };
+        
+        let song = Song {
+            version,
+            time: Timing {
+                wait,
+                loop_range: LoopRange {
+                    start,
+                    end
+                }
+            },
+            tracks
+        };
+        
+        Ok(song)
+    }
+}

src/sound/playback.rs

@@ -0,0 +1,512 @@
+use std::mem::MaybeUninit;
+
+use crate::sound::organya::Song as Organya;
+use crate::sound::stuff::*;
+use crate::sound::wav::*;
+use crate::sound::wave_bank::SoundBank;
+
+pub struct PlaybackEngine {
+    song: Organya,
+    lengths: [u8; 8],
+    swaps: [usize; 8],
+    keys: [u8; 8],
+    track_buffers: [RenderBuffer; 136],
+    output_format: WavFormat,
+    play_pos: i32,
+    frames_this_tick: usize,
+    frames_per_tick: usize,
+    pub loops: usize,
+}
+
+pub struct PlaybackState {
+    song: Organya,
+    play_pos: i32,
+}
+
+impl PlaybackEngine {
+    pub fn new(song: Organya, samples: &SoundBank) -> Self {
+
+        // Octave 0 Track 0 Swap 0
+        // Octave 0 Track 1 Swap 0
+        // ...
+        // Octave 1 Track 0 Swap 0
+        // ...
+        // Octave 0 Track 0 Swap 1
+        // octave * 8 + track + swap
+        // 128..136: Drum Tracks
+        let mut buffers: [MaybeUninit<RenderBuffer>; 136] = unsafe {
+            MaybeUninit::uninit().assume_init()
+        };
+
+        // track
+        for i in 0..8 {
+            let sound_index = song.tracks[i].inst.inst as usize;
+
+            // WAVE100 uses 8-bit signed audio, but wav audio wants 8-bit unsigned.
+            // On 2s complement system, we can simply flip the top bit
+            // No need to cast to u8 here because the sound bank data is one big &[u8].
+            let sound = samples.get_wave(sound_index)
+                .iter()
+                .map(|&x| x ^ 128)
+                .collect();
+
+            let format = WavFormat { channels: 1, sample_rate: 22050, bit_depth: 8 };
+
+            let rbuf = RenderBuffer::new_organya(WavSample { format, data: sound });
+
+            // octave
+            for j in 0..8 {
+                // swap
+                for &k in &[0, 64] {
+                    buffers[i + (j * 8) + k] = MaybeUninit::new(rbuf.clone());
+                }
+            }
+        }
+
+        for (inst, buf) in song.tracks[8..].iter().zip(buffers[128..].iter_mut()) {
+            *buf =
+                MaybeUninit::new(
+                    RenderBuffer::new(
+                        // FIXME: *frustrated screaming*
+                        samples.samples[inst.inst.inst as usize].clone()
+                    )
+                );
+        }
+
+        let frames_per_tick = (44100 / 1000) * song.time.wait as usize;
+
+        PlaybackEngine {
+            song,
+            lengths: [0; 8],
+            swaps: [0; 8],
+            keys: [255; 8],
+            track_buffers: unsafe { std::mem::transmute(buffers) },
+            play_pos: 0,
+            output_format: WavFormat {
+                channels: 2,
+                sample_rate: 44100,
+                bit_depth: 16,
+            },
+            frames_this_tick: 0,
+            frames_per_tick,
+            loops: 1,
+        }
+    }
+
+    pub fn set_sample_rate(&mut self, sample_rate: usize) {
+        self.output_format.sample_rate = sample_rate as u32;
+        self.frames_per_tick = (sample_rate / 1000) * self.song.time.wait as usize;
+    }
+
+    pub fn get_state(&self) -> PlaybackState {
+        PlaybackState {
+            song: self.song.clone(),
+            play_pos: self.play_pos,
+        }
+    }
+
+    pub fn set_state(&mut self, state: PlaybackState, samples: &SoundBank) {
+        self.start_song(state.song, samples);
+        self.play_pos = state.play_pos;
+    }
+
+    pub fn start_song(&mut self, song: Organya, samples: &SoundBank) {
+        for i in 0..8 {
+            let sound_index = song.tracks[i].inst.inst as usize;
+            let sound = samples.get_wave(sound_index)
+                .iter()
+                .map(|&x| x ^ 128)
+                .collect();
+
+            let format = WavFormat { channels: 1, sample_rate: 22050, bit_depth: 8 };
+
+            let rbuf = RenderBuffer::new_organya(WavSample { format, data: sound });
+
+            for j in 0..8 {
+                for &k in &[0, 64] {
+                    self.track_buffers[i + (j * 8) + k] = rbuf.clone();
+                }
+            }
+        }
+
+        for (inst, buf) in song.tracks[8..].iter().zip(self.track_buffers[128..].iter_mut()) {
+            *buf = RenderBuffer::new(samples.samples[inst.inst.inst as usize].clone());
+        }
+
+        self.song = song;
+        self.play_pos = 0;
+        self.frames_per_tick = (self.output_format.sample_rate as usize / 1000) * self.song.time.wait as usize;
+        self.frames_this_tick = 0;
+        for i in self.lengths.iter_mut() { *i = 0 };
+        for i in self.swaps.iter_mut() { *i = 0 };
+        for i in self.keys.iter_mut() { *i = 255 };
+    }
+
+    #[allow(unused)]
+    pub fn set_position(&mut self, position: i32) {
+        self.play_pos = position;
+    }
+
+    pub fn get_total_samples(&self) -> u32 {
+        let ticks_intro = self.song.time.loop_range.start;
+        let ticks_loop = self.song.time.loop_range.end - self.song.time.loop_range.start;
+        let ticks_total = ticks_intro + ticks_loop + (ticks_loop * self.loops as i32);
+
+        self.frames_per_tick as u32 * ticks_total as u32
+    }
+
+    fn update_play_state(&mut self) {
+        for track in 0..8 {
+            if let Some(note) =
+            self.song.tracks[track].notes.iter().find(|x| x.pos == self.play_pos) {
+                // New note
+                //eprintln!("{:?}", &self.keys);
+                if note.key != 255 {
+                    if self.keys[track] == 255 { // New
+                        let octave = (note.key / 12) * 8;
+                        let j = octave as usize + track + self.swaps[track];
+                        for k in 0..16 {
+                            let swap = if k >= 8 { 64 } else { 0 };
+                            let key = note.key % 12;
+                            let p_oct = k % 8;
+
+                            let freq = org_key_to_freq(key + p_oct * 12, self.song.tracks[track].inst.freq as i16);
+
+                            let l = p_oct as usize * 8 + track + swap;
+                            self.track_buffers[l].set_frequency(freq as u32);
+                            self.track_buffers[l].organya_select_octave(p_oct as usize, self.song.tracks[track].inst.pipi != 0);
+                        }
+                        self.track_buffers[j].looping = true;
+                        self.track_buffers[j].playing = true;
+                        // last playing key
+                        self.keys[track] = note.key;
+                    } else if self.keys[track] == note.key { // Same
+                        //assert!(self.lengths[track] == 0);
+                        let octave = (self.keys[track] / 12) * 8;
+                        let j = octave as usize + track + self.swaps[track];
+                        if self.song.tracks[track].inst.pipi == 0 {
+                            self.track_buffers[j].looping = false;
+                        }
+                        self.swaps[track] += 64;
+                        self.swaps[track] %= 128;
+                        let j = octave as usize + track + self.swaps[track];
+                        self.track_buffers[j].organya_select_octave(note.key as usize / 12, self.song.tracks[track].inst.pipi != 0);
+                        self.track_buffers[j].looping = true;
+                        self.track_buffers[j].playing = true;
+                    } else { // change
+                        let octave = (self.keys[track] / 12) * 8;
+                        let j = octave as usize + track + self.swaps[track];
+                        if self.song.tracks[track].inst.pipi == 0 {
+                            self.track_buffers[j].looping = false;
+                        }
+                        self.swaps[track] += 64;
+                        self.swaps[track] %= 128;
+                        let octave = (note.key / 12) * 8;
+                        let j = octave as usize + track + self.swaps[track];
+                        for k in 0..16 {
+                            let swap = if k >= 8 { 64 } else { 0 };
+                            let key = note.key % 12;
+                            let p_oct = k % 8;
+
+                            let freq = org_key_to_freq(key + p_oct * 12, self.song.tracks[track].inst.freq as i16);
+                            let l = p_oct as usize * 8 + track + swap;
+                            self.track_buffers[l].set_frequency(freq as u32);
+                            self.track_buffers[l].organya_select_octave(p_oct as usize, self.song.tracks[track].inst.pipi != 0);
+                        }
+                        self.track_buffers[j].looping = true;
+                        self.track_buffers[j].playing = true;
+                        self.keys[track] = note.key;
+                    }
+
+                    self.lengths[track] = note.len;
+                }
+
+                if self.keys[track] != 255 {
+                    let octave = (self.keys[track] / 12) * 8;
+                    let j = octave as usize + track + self.swaps[track];
+
+                    if note.vol != 255 {
+                        let vol = org_vol_to_vol(note.vol);
+                        self.track_buffers[j].set_volume(vol);
+                    }
+
+                    if note.pan != 255 {
+                        let pan = org_pan_to_pan(note.pan);
+                        self.track_buffers[j].set_pan(pan);
+                    }
+                }
+            }
+
+            if self.lengths[track] == 0 {
+                if self.keys[track] != 255 {
+                    let octave = (self.keys[track] / 12) * 8;
+                    let j = octave as usize + track + self.swaps[track];
+                    if self.song.tracks[track].inst.pipi == 0 {
+                        self.track_buffers[j].looping = false;
+                    }
+                    self.keys[track] = 255;
+                }
+            }
+
+            self.lengths[track] = self.lengths[track].saturating_sub(1);
+        }
+
+        for i in 8..16 {
+            let j = i + 120;
+
+            let notes = &self.song.tracks[i].notes;
+
+            // start a new note
+            // note (hah) that drums are unaffected by length and pi values. This is the only case we have to handle.
+            if let Some(note) =
+            notes.iter().find(|x| x.pos == self.play_pos) {
+
+                // FIXME: Add constants for dummy values
+                if note.key != 255 {
+                    let freq = org_key_to_drum_freq(note.key);
+                    self.track_buffers[j].set_frequency(freq as u32);
+                    self.track_buffers[j].set_position(0);
+                    self.track_buffers[j].playing = true;
+                }
+
+                if note.vol != 255 {
+                    let vol = org_vol_to_vol(note.vol);
+                    self.track_buffers[j].set_volume(vol);
+                }
+
+                if note.pan != 255 {
+                    let pan = org_pan_to_pan(note.pan);
+                    self.track_buffers[j].set_pan(pan);
+                }
+            }
+        }
+    }
+
+    pub fn render_to(&mut self, buf: &mut [u16]) -> usize {
+        for (i, frame) in buf.iter_mut().enumerate() {
+            if self.frames_this_tick == 0 {
+                self.update_play_state()
+            }
+
+            mix(std::slice::from_mut(frame), self.output_format, &mut self.track_buffers);
+
+            self.frames_this_tick += 1;
+
+            if self.frames_this_tick == self.frames_per_tick {
+                self.play_pos += 1;
+
+                if self.play_pos == self.song.time.loop_range.end {
+                    self.play_pos = self.song.time.loop_range.start;
+
+                    if self.loops == 0 {
+                        return i + 1;
+                    }
+
+                    self.loops -= 1;
+                }
+
+                self.frames_this_tick = 0;
+            }
+        }
+
+        buf.len()
+    }
+}
+
+// TODO: Create a MixingBuffer or something...
+fn mix(dst: &mut [u16], dst_fmt: WavFormat, srcs: &mut [RenderBuffer]) {
+    let freq = dst_fmt.sample_rate as f64;
+
+    for buf in srcs {
+        if buf.playing {
+            // index into sound samples
+            let advance = buf.frequency as f64 / freq;
+
+            let vol = centibel_to_scale(buf.volume);
+
+            let (pan_l, pan_r) =
+                match buf.pan.signum() {
+                    0 => (1.0, 1.0),
+                    1 => (centibel_to_scale(-buf.pan), 1.0),
+                    -1 => (1.0, centibel_to_scale(buf.pan)),
+                    _ => unsafe { std::hint::unreachable_unchecked() }
+                };
+
+            fn clamp<T: Ord>(v: T, limit: T) -> T {
+                if v > limit {
+                    limit
+                } else {
+                    v
+                }
+            }
+
+            // s1: sample 1
+            // s2: sample 2
+            // sp: previous sample (before s1)
+            // sn: next sample (after s2)
+            // mu: position to interpolate for
+            fn cubic_interp(s1: f32, s2: f32, sp: f32, sn: f32, mu: f32) -> f32 {
+                let mu2 = mu * mu;
+                let a0 = sn - s2 - sp + s1;
+                let a1 = sp - s1 - a0;
+                let a2 = s2 - sp;
+                let a3 = s1;
+
+                a0 * mu * mu2 + a1 * mu2 + a2 * mu + a3
+            }
+
+            #[allow(unused_variables)]
+
+            for frame in dst.iter_mut() {
+                let pos = buf.position as usize + buf.base_pos;
+                // -1..1
+                let s1 = (buf.sample.data[pos] as f32 - 128.0) / 128.0;
+                let s2 = (buf.sample.data[clamp(pos + 1, buf.base_pos + buf.len - 1)] as f32 - 128.0) / 128.0;
+                let s3 = (buf.sample.data[clamp(pos + 2, buf.base_pos + buf.len - 1)] as f32 - 128.0) / 128.0;
+                let s4 = (buf.sample.data[pos.saturating_sub(1)] as f32 - 128.0) / 128.0;
+
+                use std::f32::consts::PI;
+
+                let r1 = buf.position.fract() as f32;
+                let r2 = (1.0 - f32::cos(r1 * PI)) / 2.0;
+
+                //let s = s1; // No interp
+                //let s = s1 + (s2 - s1) * r1; // Linear interp
+                //let s = s1 * (1.0 - r2) + s2 * r2; // Cosine interp
+                let s = cubic_interp(s1, s2, s4, s3, r1); // Cubic interp
+                // Ideally we want sinc/lanczos interpolation, since that's what DirectSound appears to use.
+
+                // -128..128
+                let sl = s * pan_l * vol * 128.0;
+                let sr = s * pan_r * vol * 128.0;
+
+                buf.position += advance;
+
+                if buf.position as usize >= buf.len {
+                    if buf.looping && buf.nloops != 1 {
+                        buf.position %= buf.len as f64;
+                        if buf.nloops != -1 {
+                            buf.nloops -= 1;
+                        }
+                    } else {
+                        buf.position = 0.0;
+                        buf.playing = false;
+                        break;
+                    }
+                }
+
+                let [mut l, mut r] = frame.to_le_bytes();
+                // -128..127
+                let xl = (l ^ 128) as i8;
+                let xr = (r ^ 128) as i8;
+
+                // 0..255
+                l = xl.saturating_add(sl as i8) as u8 ^ 128;
+                r = xr.saturating_add(sr as i8) as u8 ^ 128;
+
+                *frame = u16::from_le_bytes([l, r]);
+            }
+        }
+    }
+}
+
+pub fn centibel_to_scale(a: i32) -> f32 {
+    f32::powf(10.0, a as f32 / 2000.0)
+}
+
+#[derive(Clone)]
+pub struct RenderBuffer {
+    pub position: f64,
+    pub frequency: u32,
+    pub volume: i32,
+    pub pan: i32,
+    pub sample: WavSample,
+    pub playing: bool,
+    pub looping: bool,
+    pub base_pos: usize,
+    pub len: usize,
+    // -1 = infinite
+    pub nloops: i32,
+}
+
+impl RenderBuffer {
+    pub fn new(sample: WavSample) -> RenderBuffer {
+        RenderBuffer {
+            position: 0.0,
+            frequency: sample.format.sample_rate,
+            volume: 0,
+            pan: 0,
+            len: sample.data.len(),
+            sample,
+            playing: false,
+            looping: false,
+            base_pos: 0,
+            nloops: -1,
+        }
+    }
+
+    pub fn new_organya(mut sample: WavSample) -> RenderBuffer {
+        let wave = sample.data.clone();
+        sample.data.clear();
+
+        for size in &[256_usize, 256, 128, 128, 64, 32, 16, 8] {
+            let step = 256 / size;
+            let mut acc = 0;
+
+            for _ in 0..*size {
+                sample.data.push(wave[acc]);
+                acc += step;
+
+                if acc >= 256 {
+                    acc = 0;
+                }
+            }
+        }
+
+        RenderBuffer::new(sample)
+    }
+
+    #[inline]
+    pub fn organya_select_octave(&mut self, octave: usize, pipi: bool) {
+        const OFFS: &[usize] = &[0x000, 0x100,
+            0x200, 0x280,
+            0x300, 0x340,
+            0x360, 0x370];
+        const LENS: &[usize] = &[256_usize, 256, 128, 128, 64, 32, 16, 8];
+        self.base_pos = OFFS[octave];
+        self.len = LENS[octave];
+        self.position %= self.len as f64;
+        if pipi && !self.playing {
+            self.nloops = ((octave + 1) * 4) as i32;
+        }
+    }
+
+    #[inline]
+    pub fn set_frequency(&mut self, frequency: u32) {
+        //assert!(frequency >= 100 && frequency <= 100000);
+        //dbg!(frequency);
+        self.frequency = frequency;
+    }
+
+    #[inline]
+    pub fn set_volume(&mut self, volume: i32) {
+        assert!(volume >= -10000 && volume <= 0);
+
+        self.volume = volume;
+    }
+
+    #[inline]
+    pub fn set_pan(&mut self, pan: i32) {
+        assert!(pan >= -10000 && pan <= 10000);
+
+        self.pan = pan;
+    }
+
+    #[inline]
+    #[allow(unused)]
+    pub fn set_position(&mut self, position: u32) {
+        assert!(position < self.sample.data.len() as u32 / self.sample.format.bit_depth as u32);
+
+        self.position = position as f64;
+    }
+}

src/sound/stuff.rs

@@ -0,0 +1,36 @@
+pub const FRQ_TBL: [i16; 12] = [
+    261,278,294,311,329,349,371,391,414,440,466,494
+];
+
+pub const PAN_TBL: [i16; 13] = [
+    0,43,86,129,172,215,256,297,340,383,426,469,512
+];
+
+pub const OCT_TBL: [i16; 8] = [
+    32,64,64,128,128,128,128,128
+];
+
+pub fn org_key_to_freq(key: u8, a: i16) -> i32 {
+    let (oct, pitch) = org_key_to_oct_pitch(key);
+
+    let freq = FRQ_TBL[pitch as usize] as f32;
+    let oct  = OCT_TBL[oct as usize] as f32;
+
+    (freq * oct) as i32 + (a as i32 - 1000)
+}
+
+pub fn org_key_to_drum_freq(key: u8) -> i32  {
+    key as i32 * 800 + 100
+}
+
+pub fn org_pan_to_pan(pan: u8) -> i32 {
+    (PAN_TBL[pan as usize] as i32 - 256) * 10
+}
+
+pub fn org_vol_to_vol(vol: u8) -> i32 {
+    (vol as i32 - 255) * 8
+}
+
+pub fn org_key_to_oct_pitch(key: u8) -> (u8, u8) {
+    (key/12, key%12)
+}

src/sound/wav.rs

@@ -0,0 +1,120 @@
+#[derive(Copy, Clone, Eq, PartialEq, Debug)]
+pub struct RiffChunk {
+    id: [u8; 4],
+    length: u32
+}
+
+use std::fmt;
+
+impl fmt::Display for RiffChunk {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        use std::ascii::escape_default as esc;
+        
+        write!(f, "chunk \"{}{}{}{}\", length: {}",
+            esc(self.id[0]),
+            esc(self.id[1]),
+            esc(self.id[2]),
+            esc(self.id[3]),
+            self.length
+        )
+    }
+}
+
+#[derive(Copy, Clone, Eq, PartialEq, Debug)]
+pub struct WavFormat {
+    pub channels: u16,
+    pub sample_rate: u32,
+    pub bit_depth: u16
+}
+
+impl fmt::Display for WavFormat {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{} channels, {} Hz, {}-bit",
+            self.channels,
+            self.sample_rate,
+            self.bit_depth
+        )
+    }
+}
+
+#[derive(Clone)]
+pub struct WavSample {
+    pub format: WavFormat,
+    pub data: Vec<u8>
+}
+
+impl fmt::Display for WavSample {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}, {} samples",
+            self.format,
+            // num_bytes / bytes_per_sample
+            self.data.len() / ((self.format.bit_depth / 8) * self.format.channels) as usize
+        )
+    }
+}
+
+use byteorder::{LE, ReadBytesExt};
+use std::io;
+
+impl RiffChunk {
+    pub fn read_from<R: io::Read>(mut f: R) -> io::Result<RiffChunk> {
+        let mut id = [0; 4];
+        
+        f.read_exact(&mut id)?;
+        let length = f.read_u32::<LE>()?;
+        
+        Ok(RiffChunk { id, length })
+    }
+}
+
+impl WavSample {
+    pub fn read_from<R: io::Read>(mut f: R) -> io::Result<WavSample> {
+        let riff = RiffChunk::read_from(&mut f)?;
+        
+        match &riff.id {
+            b"RIFF" => {},
+            b"RIFX" => panic!("Cannot handle RIFX data!"),
+            _       => panic!("Expected RIFF signature, found {}", riff)
+        }
+        
+        let mut rfmt = [0; 4];
+        
+        f.read_exact(&mut rfmt)?;
+        
+        assert_eq!(rfmt, *b"WAVE");
+        
+        let fmt = RiffChunk::read_from(&mut f)?;
+        
+        assert_eq!(fmt.id, *b"fmt ");
+        //assert_eq!(fmt.length, 16);
+        
+        let afmt = f.read_u16::<LE>()?;
+        
+        debug_assert!(afmt == 1);
+        
+        let channels = f.read_u16::<LE>()?;
+        let samples  = f.read_u32::<LE>()?;
+        let _brate = f.read_u32::<LE>()?;
+        let _balgn = f.read_u16::<LE>()?;
+        let bits     = f.read_u16::<LE>()?;
+        
+        let data = RiffChunk::read_from(&mut f)?;
+        
+        assert_eq!(data.id, *b"data");
+        
+        let mut buf = vec![0; data.length as usize];
+        
+        f.read_exact(&mut buf)?;
+        
+        Ok(
+            WavSample {
+                format: WavFormat {
+                    channels,
+                    sample_rate: samples,
+                    bit_depth: bits
+                },
+                data: buf
+            }
+        )
+    }
+}

src/sound/wave_bank.rs

@@ -0,0 +1,45 @@
+use crate::sound::wav;
+
+use std::io;
+use std::fmt;
+
+pub struct SoundBank {
+    // FIXME: would prefer Box<[u8; 25600]>
+    pub wave100: Box<[u8]>,
+    
+    pub samples: Vec<wav::WavSample>
+}
+
+impl fmt::Display for SoundBank {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        writeln!(f, "WAVE100: {:2X?}...", &self.wave100[..8])?;
+        
+        for sample in self.samples.iter() {
+            writeln!(f, "{}", sample)?;
+        }
+        
+        Ok(())
+    }
+}
+
+impl SoundBank {
+    pub fn load_from<R: io::Read>(mut f: R) -> io::Result<SoundBank> {
+        // no box [0; 25600] yet
+        let mut wave100 = vec![0; 25600].into_boxed_slice();
+        
+        f.read_exact(&mut *wave100)?;
+        
+        let mut samples = Vec::with_capacity(16);
+        
+        loop {
+            match wav::WavSample::read_from(&mut f) {
+                Ok(sample) => samples.push(sample),
+                Err(_)     => return Ok(SoundBank { wave100, samples })
+            }
+        }
+    }
+    
+    pub fn get_wave(&self, index: usize) -> &[u8] {
+        &self.wave100[index*256..(index+1)*256]
+    }
+}