HexoDSP/src/dsp/node_smap.rs

// Copyright (c) 2021 Weird Constructor <weirdconstructor@gmail.com>
// This is a part of HexoDSP. Released under (A)GPLv3 or any later.
// See README.md and COPYING for details.

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

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

#[macro_export]
macro_rules! fa_smap_mode { ($formatter: expr, $v: expr, $denorm_v: expr) => { {
    let s =
        match ($v.round() as usize) {
            0  => "Unipolar",
            1  => "Bipolar",
            2  => "UniInv",
            3  => "BiInv",
            _  => "",
        };
    write!($formatter, "{}", s)
} } }

/// A simple amplifier
#[derive(Debug, Clone)]
pub struct SMap {
}

impl SMap {
    pub fn new(_nid: &NodeId) -> Self {
        Self {
        }
    }
    pub const inp : &'static str =
        "SMap inp\nSignal input\nRange: (-1..1)\n";
    pub const min : &'static str =
        "SMap min\nMinimum of the output signal range.\nRange: (0..1)\n";
    pub const max : &'static str =
        "SMap max\nMaximum of the output signal range.\nRange: (0..1)\n";
    pub const clip : &'static str =
        "SMap clip\nThe 'clip' mode allows you to limit the output \
        exactly to the 'min'/'max' range. If this is off, the output \
        may be outside the output signal range.";
    pub const mode : &'static str =
        "SMap mode\nThis mode defines what kind of input signal is expected \
        and how it will be mapped to the output 'min'/'max' range. \
        These modes are available:\
        \nUnipolar (0..1) / Bipolar  (-1..1)\
        \nUniInv   (1..0) / BiInv    (1..-1)";
    pub const sig : &'static str =
        "SMap sig\nMapped signal output\nRange: (-1..1)\n";
    pub const DESC : &'static str =
r#"Simple Signal Range Mapper

This node allows to map an unipolar (0..1) or bipolar signal (-1..1) to a defined 'min'/'max' signal range.

See also the 'Map' node for a more sophisticated version of this.
"#;
    pub const HELP : &'static str =
r#"SMap - Simple Signal Range Mapper

This node allows to map an unipolar (0..1) or bipolar signal (-1..1)
to a defined 'min'/'max' signal range.

The 'clip' mode allows you to limit the output exactly to the 'min'/'max'
range. If this is off, the output may be outside the output signal
range if the input signal is outside the input signal range.

The 'input' mode allows you to choose between 4 options:

    * Unipolar (0..1)
    * Bipolar  (-1..1)
    * UniInv   (1..0)
    * BiInv    (1..-1)

The inverse settings will map 1 to 'min' and 0 to 'max' for 'UniInv'.
And 1 to 'min' and -1 to 'max' for 'BiInv'.

For a more sophisticated version of this node see also 'Map'.
"#;

}

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

    fn set_sample_rate(&mut self, _srate: f32) { }
    fn reset(&mut self) { }

    #[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::{out, inp, at};

        let inp  = inp::SMap::inp(inputs);
        let min  = inp::SMap::min(inputs);
        let max  = inp::SMap::max(inputs);
        let out  = out::SMap::sig(outputs);

        let clip = at::SMap::clip(atoms);
        let mode = at::SMap::mode(atoms);

        let mut last_val = 0.0;

        match (mode.i(), clip.i()) {
            (0, 0) => {
                for frame in 0..ctx.nframes() {
                    let s   = inp.read(frame);
                    let min = min.read(frame);
                    let max = max.read(frame);
                    last_val = s;
                    out.write(frame, min + (max - min) * s);
                }
            },
            (0, 1) => {
                for frame in 0..ctx.nframes() {
                    let s   = inp.read(frame);
                    let min = min.read(frame);
                    let max = max.read(frame);
                    let s = s.clamp(0.0, 1.0);
                    last_val = s;
                    out.write(frame, min + (max - min) * s);
                }
            },
            (1, 0) => {
                for frame in 0..ctx.nframes() {
                    let s   = inp.read(frame);
                    let min = min.read(frame);
                    let max = max.read(frame);
                    let s = (s + 1.0) * 0.5;
                    out.write(frame, min + (max - min) * s);
                }
            },
            (1, 1) => {
                for frame in 0..ctx.nframes() {
                    let s   = inp.read(frame);
                    let min = min.read(frame);
                    let max = max.read(frame);
                    let s = ((s + 1.0) * 0.5).clamp(0.0, 1.0);
                    out.write(frame, min + (max - min) * s);
                }
            },
            (2, 0) => {
                for frame in 0..ctx.nframes() {
                    let s   = inp.read(frame);
                    let min = min.read(frame);
                    let max = max.read(frame);
                    let s   = 1.0 - s;
                    last_val = s;
                    out.write(frame, min + (max - min) * s);
                }
            },
            (2, 1) => {
                for frame in 0..ctx.nframes() {
                    let s   = inp.read(frame);
                    let min = min.read(frame);
                    let max = max.read(frame);
                    let s   = 1.0 - s.clamp(0.0, 1.0);
                    last_val = s;
                    out.write(frame, min + (max - min) * s);
                }
            },
            (3, 0) => {
                for frame in 0..ctx.nframes() {
                    let s   = inp.read(frame);
                    let min = min.read(frame);
                    let max = max.read(frame);
                    let s = 1.0 - ((s + 1.0) * 0.5);
                    out.write(frame, min + (max - min) * s);
                }
            },
            (3, 1) => {
                for frame in 0..ctx.nframes() {
                    let s   = inp.read(frame);
                    let min = min.read(frame);
                    let max = max.read(frame);
                    let s = 1.0 - ((s + 1.0) * 0.5).clamp(0.0, 1.0);
                    out.write(frame, min + (max - min) * s);
                }
            },
            _ => {},
        }

        ctx_vals[0].set(last_val);
    }
}