tek/crates/device/src/sampler/sampler_midi.rs

use crate::*;

pub type MidiSample = (Option<u7>, Arc<RwLock<crate::Sample>>);

impl Sampler {

    /// Create [Voice]s from [Sample]s in response to MIDI input.
    pub fn process_midi_in (&mut self, scope: &ProcessScope) {
        let Sampler { midi_in, mapped, voices, .. } = self;
        if let Some(ref midi_in) = midi_in {
            for RawMidi { time, bytes } in midi_in.port().iter(scope) {
                if let LiveEvent::Midi { message, .. } = LiveEvent::parse(bytes).unwrap() {
                    match message {
                        MidiMessage::NoteOn { ref key, ref vel } => {
                            if let Some(ref sample) = mapped[key.as_int() as usize] {
                                voices.write().unwrap().push(Sample::play(sample, time as usize, vel));
                            }
                        },
                        MidiMessage::Controller { controller: _, value: _ } => {
                            // TODO
                        }
                        _ => {}
                    }
                }
            }
        }
    }

}

impl Sample {
    pub fn handle_cc (&mut self, controller: u7, value: u7) {
        let percentage = value.as_int() as f64 / 127.;
        match controller.as_int() {
            20 => {
                self.start = (percentage * self.end as f64) as usize;
            },
            21 => {
                let length = self.channels[0].len();
                self.end = length.min(
                    self.start + (percentage * (length as f64 - self.start as f64)) as usize
                );
            },
            22 => { /*attack*/ },
            23 => { /*decay*/  },
            24 => {
                self.gain = percentage as f32 * 2.0;
            },
            26 => { /* pan */ }
            25 => { /* pitch */ }
            _ => {}
        }
    }
}