HexoDSP/src/dsp/node_cqnt.rs

// Copyright (c) 2021 Weird Constructor <weirdconstructor@gmail.com>
// This file is a part of HexoDSP. Released under GPL-3.0-or-later.
// See README.md and COPYING for details.

use crate::nodes::{NodeAudioContext, NodeExecContext};
use crate::dsp::{NodeId, SAtom, ProcBuf, DspNode, LedPhaseVals, NodeContext};
use crate::dsp::helpers::{CtrlPitchQuantizer, ChangeTrig};

#[macro_export]
macro_rules! fa_cqnt { ($formatter: expr, $v: expr, $denorm_v: expr) => { {
    write!($formatter, "?")
} } }

#[macro_export]
macro_rules! fa_cqnt_omin { ($formatter: expr, $v: expr, $denorm_v: expr) => { {
    let s =
        match ($v.round() as usize) {
            0  => "-0",
            1  => "-1",
            2  => "-2",
            3  => "-3",
            4  => "-4",
            _  => "?",
        };
    write!($formatter, "{}", s)
} } }

#[macro_export]
macro_rules! fa_cqnt_omax { ($formatter: expr, $v: expr, $denorm_v: expr) => { {
    let s =
        match ($v.round() as usize) {
            0  => "+0",
            1  => "+1",
            2  => "+2",
            3  => "+3",
            4  => "+4",
            _  => "?",
        };
    write!($formatter, "{}", s)
} } }

/// A control signal to pitch quantizer/converter
#[derive(Debug, Clone)]
pub struct CQnt {
    quant:       Box<CtrlPitchQuantizer>,
    change_trig: ChangeTrig,
}

impl CQnt {
    pub fn new(_nid: &NodeId) -> Self {
        Self {
            quant:       Box::new(CtrlPitchQuantizer::new()),
            change_trig: ChangeTrig::new(),
        }
    }
    pub const inp : &'static str =
        "CQnt inp\nThe unipolar input signal that is to be mapped to the \
        selected pitch range.\nRange: (0..1)";
    pub const oct : &'static str =
        "CQnt oct\nThe octave offset from A4.\nRange: (-1..1)";
    pub const omin : &'static str =
        "CQnt omin\nThe minimum octave of the range. If 0 it will be 'oct'.\nRange: (-1..1)";
    pub const omax : &'static str =
        "CQnt omax\nThe maximum octave of the range. If 0 it will be 'oct'.\nRange: (-1..1)";
    pub const sig : &'static str =
        "CQnt sig\nThe output pitch signal.\nRange: (-1..1)";
    pub const t : &'static str =
        "CQnt t\nEverytime the quantizer snaps to a new pitch, it will \
        emit a short trigger on this signal output. This is useful \
        to trigger for example an envelope.";
    pub const keys : &'static str =
        "CQnt keys\nHere you can select the individual notes of the range. \
        If no note is selected, it's the same as if all notes were selected.";
    pub const DESC : &'static str =
r#"Ctrl Pitch Quantizer

This special quantizer maps the unipolar 0..1 control signal input range on 'inp' evenly to the selected keys and octaves.
"#;
    pub const HELP : &'static str =
r#"CQnt - A control signal to pitch quantizer

This is a specialized control signal quantizer to generate a pitch/frequency
from a signal within the 0..1 range. It does not quantize a typical -1..1
frequency signal like the 'Quant' node.

In contrast to 'Quant', this quantizer maps the incoming signal evenly
to the available note range. It will result in more evenly played notes
if you sweep accross the input signal range.
"#;
}

impl DspNode for CQnt {
    fn outputs() -> usize { 1 }

    fn set_sample_rate(&mut self, srate: f32) {
        self.change_trig.set_sample_rate(srate);
    }

    fn reset(&mut self) {
        self.change_trig.reset();
    }


    #[inline]
    fn process<T: NodeAudioContext>(
        &mut self, ctx: &mut T, _ectx: &mut NodeExecContext,
        _nctx: &NodeContext,
        atoms: &[SAtom], inputs: &[ProcBuf],
        outputs: &mut [ProcBuf], ctx_vals: LedPhaseVals)
    {
        use crate::dsp::{at, out_buf, inp, denorm};

        let inp = inp::CQnt::inp(inputs);
        let oct = inp::CQnt::oct(inputs);
        let mut out = out_buf::CQnt::sig(outputs);
        let mut t   = out_buf::CQnt::t(outputs);
        let keys = at::CQnt::keys(atoms);
        let omin = at::CQnt::omin(atoms);
        let omax = at::CQnt::omax(atoms);

        self.quant.update_keys(keys.i(), omin.i(), omax.i());

        for frame in 0..ctx.nframes() {
            let pitch =
                self.quant.signal_to_pitch(
                    denorm::CQnt::inp(inp, frame));

            t.write(frame, self.change_trig.next(pitch));
            out.write(frame, pitch + denorm::CQnt::oct(oct, frame));
        }

        let last_pitch = self.quant.last_key_pitch();
        ctx_vals[1].set(last_pitch * 10.0 + 0.0001);
        ctx_vals[0].set((last_pitch * 10.0 - 0.5) * 2.0);
    }
}