tek/crates/sampler/src/sampler_model.rs

use crate::*;

/// The sampler device plays sounds in response to MIDI notes.
#[derive(Debug)]
pub struct Sampler {
    pub name:        String,
    pub mapped:      [Option<Arc<RwLock<Sample>>>;128],
    pub recording:   Option<(usize, Arc<RwLock<Sample>>)>,
    pub unmapped:    Vec<Arc<RwLock<Sample>>>,
    pub voices:      Arc<RwLock<Vec<Voice>>>,
    pub midi_in:     Option<JackMidiIn>,
    pub audio_ins:   Vec<JackAudioIn>,
    pub input_meter: Vec<f32>,
    pub audio_outs:  Vec<JackAudioOut>,
    pub buffer:      Vec<Vec<f32>>,
    pub output_gain: f32,
    pub cursor:  (usize, usize),
    pub editing: Option<Arc<RwLock<Sample>>>,
    pub mode:    Option<SamplerMode>,
    /// Size of actual notes area
    pub size:    Measure<TuiOut>,
    /// Lowest note displayed
    pub note_lo: AtomicUsize,
    pub note_pt: AtomicUsize,
    pub color:   ItemPalette
}

impl Default for Sampler {
    fn default () -> Self {
        Self {
            midi_in:     None,
            audio_ins:   vec![],
            input_meter: vec![0.0;2],
            audio_outs:  vec![],
            name:        "tek_sampler".to_string(),
            mapped:      [const { None };128],
            unmapped:    vec![],
            voices:      Arc::new(RwLock::new(vec![])),
            buffer:      vec![vec![0.0;16384];2],
            output_gain: 1.,
            recording:   None,
            mode:        None,
            cursor:      (0, 0),
            editing:     None,
            size:        Default::default(),
            note_lo:     0.into(),
            note_pt:     0.into(),
            color:       Default::default(),
        }
    }
}

impl Sampler {
    pub fn new (
        jack:       &Jack,
        name:       impl AsRef<str>,
        midi_from:  &[PortConnect],
        audio_from: &[&[PortConnect];2],
        audio_to:   &[&[PortConnect];2],
    ) -> Usually<Self> {
        let name = name.as_ref();
        Ok(Self {
            midi_in: Some(JackMidiIn::new(jack, format!("M/{name}"), midi_from)?),
            audio_ins: vec![
                JackAudioIn::new(jack, &format!("L/{name}"), audio_from[0])?,
                JackAudioIn::new(jack, &format!("R/{name}"), audio_from[1])?,
            ],
            audio_outs: vec![
                JackAudioOut::new(jack, &format!("{name}/L"), audio_to[0])?,
                JackAudioOut::new(jack, &format!("{name}/R"), audio_to[1])?,
            ],
            ..Default::default()
        })
    }
    pub fn cancel_recording (&mut self) {
        self.recording = None;
    }
    pub fn begin_recording (&mut self, index: usize) {
        self.recording = Some((
            index,
            Arc::new(RwLock::new(Sample::new("Sample", 0, 0, vec![vec![];self.audio_ins.len()])))
        ));
    }
    pub fn finish_recording (&mut self) -> Option<Arc<RwLock<Sample>>> {
        let recording = self.recording.take();
        if let Some((index, sample)) = recording {
            let old = self.mapped[index].clone();
            self.mapped[index] = Some(sample);
            old
        } else {
            None
        }
    }
    /// Immutable reference to sample at cursor.
    pub fn sample (&self) -> Option<&Arc<RwLock<Sample>>> {
        for (i, sample) in self.mapped.iter().enumerate() {
            if i == self.cursor.0 {
                return sample.as_ref()
            }
        }
        for (i, sample) in self.unmapped.iter().enumerate() {
            if i + self.mapped.len() == self.cursor.0 {
                return Some(sample)
            }
        }
        None
    }
}

/// A sound sample.
#[derive(Default, Debug)]
pub struct Sample {
    pub name:     Arc<str>,
    pub start:    usize,
    pub end:      usize,
    pub channels: Vec<Vec<f32>>,
    pub rate:     Option<usize>,
    pub gain:     f32,
}

impl Sample {
    pub fn new (name: impl AsRef<str>, start: usize, end: usize, channels: Vec<Vec<f32>>) -> Self {
        Self { name: name.as_ref().into(), start, end, channels, rate: None, gain: 1.0 }
    }
    pub fn play (sample: &Arc<RwLock<Self>>, after: usize, velocity: &u7) -> Voice {
        Voice {
            sample: sample.clone(),
            after,
            position: sample.read().unwrap().start,
            velocity: velocity.as_int() as f32 / 127.0,
        }
    }
}

/// A currently playing instance of a sample.
#[derive(Default, Debug, Clone)]
pub struct Voice {
    pub sample:   Arc<RwLock<Sample>>,
    pub after:    usize,
    pub position: usize,
    pub velocity: f32,
}

#[derive(Debug)]
pub enum SamplerMode {
    // Load sample from path
    Import(usize, FileBrowser),
}