Lightningbeam/daw-backend/src/audio/node_graph/nodes/vibrato.rs

271 lines
8.3 KiB
Rust

use crate::audio::node_graph::{AudioNode, NodeCategory, NodePort, Parameter, ParameterUnit, SignalType};
use crate::audio::midi::MidiEvent;
use std::f32::consts::PI;
const PARAM_RATE: u32 = 0;
const PARAM_DEPTH: u32 = 1;
const MAX_DELAY_MS: f32 = 7.0;
const BASE_DELAY_MS: f32 = 0.5;
/// Vibrato effect — periodic pitch modulation via a short modulated delay line.
///
/// 100% wet signal (no dry mix). Supports an external Mod CV input that, when
/// connected, replaces the internal sine LFO with the incoming CV signal.
pub struct VibratoNode {
name: String,
rate: f32,
depth: f32,
delay_buffer_left: Vec<f32>,
delay_buffer_right: Vec<f32>,
write_position: usize,
max_delay_samples: usize,
sample_rate: u32,
lfo_phase: f32,
inputs: Vec<NodePort>,
outputs: Vec<NodePort>,
parameters: Vec<Parameter>,
}
impl VibratoNode {
pub fn new(name: impl Into<String>) -> Self {
let name = name.into();
let inputs = vec![
NodePort::new("Audio In", SignalType::Audio, 0),
NodePort::new("Mod CV In", SignalType::CV, 1),
NodePort::new("Rate CV In", SignalType::CV, 2),
NodePort::new("Depth CV In", SignalType::CV, 3),
];
let outputs = vec![
NodePort::new("Audio Out", SignalType::Audio, 0),
];
let parameters = vec![
Parameter::new(PARAM_RATE, "Rate", 0.1, 14.0, 5.0, ParameterUnit::Frequency),
Parameter::new(PARAM_DEPTH, "Depth", 0.0, 1.0, 0.5, ParameterUnit::Generic),
];
let max_delay_samples = ((MAX_DELAY_MS / 1000.0) * 48000.0) as usize;
Self {
name,
rate: 5.0,
depth: 0.5,
delay_buffer_left: vec![0.0; max_delay_samples],
delay_buffer_right: vec![0.0; max_delay_samples],
write_position: 0,
max_delay_samples,
sample_rate: 48000,
lfo_phase: 0.0,
inputs,
outputs,
parameters,
}
}
fn read_interpolated_sample(&self, buffer: &[f32], delay_samples: f32) -> f32 {
let delay_samples = delay_samples.clamp(0.0, (self.max_delay_samples - 1) as f32);
let read_pos_float = self.write_position as f32 - delay_samples;
let read_pos_float = if read_pos_float < 0.0 {
read_pos_float + self.max_delay_samples as f32
} else {
read_pos_float
};
let read_pos_int = read_pos_float.floor() as usize;
let frac = read_pos_float - read_pos_int as f32;
let sample1 = buffer[read_pos_int % self.max_delay_samples];
let sample2 = buffer[(read_pos_int + 1) % self.max_delay_samples];
sample1 * (1.0 - frac) + sample2 * frac
}
}
impl AudioNode for VibratoNode {
fn category(&self) -> NodeCategory {
NodeCategory::Effect
}
fn inputs(&self) -> &[NodePort] {
&self.inputs
}
fn outputs(&self) -> &[NodePort] {
&self.outputs
}
fn parameters(&self) -> &[Parameter] {
&self.parameters
}
fn set_parameter(&mut self, id: u32, value: f32) {
match id {
PARAM_RATE => {
self.rate = value.clamp(0.1, 14.0);
}
PARAM_DEPTH => {
self.depth = value.clamp(0.0, 1.0);
}
_ => {}
}
}
fn get_parameter(&self, id: u32) -> f32 {
match id {
PARAM_RATE => self.rate,
PARAM_DEPTH => self.depth,
_ => 0.0,
}
}
fn process(
&mut self,
inputs: &[&[f32]],
outputs: &mut [&mut [f32]],
_midi_inputs: &[&[MidiEvent]],
_midi_outputs: &mut [&mut Vec<MidiEvent>],
sample_rate: u32,
) {
if inputs.is_empty() || outputs.is_empty() {
return;
}
if self.sample_rate != sample_rate {
self.sample_rate = sample_rate;
self.max_delay_samples = ((MAX_DELAY_MS / 1000.0) * sample_rate as f32) as usize;
self.delay_buffer_left.resize(self.max_delay_samples, 0.0);
self.delay_buffer_right.resize(self.max_delay_samples, 0.0);
self.write_position = 0;
}
let input = inputs[0];
let output = &mut outputs[0];
// CV inputs — unconnected ports are filled with NaN
let mod_cv = inputs.get(1);
let rate_cv = inputs.get(2);
let depth_cv = inputs.get(3);
let frames = input.len() / 2;
let output_frames = output.len() / 2;
let frames_to_process = frames.min(output_frames);
let base_delay_samples = (BASE_DELAY_MS / 1000.0) * self.sample_rate as f32;
let max_modulation_samples = (MAX_DELAY_MS - BASE_DELAY_MS) / 1000.0 * self.sample_rate as f32;
for frame in 0..frames_to_process {
let left_in = input[frame * 2];
let right_in = input[frame * 2 + 1];
// Resolve depth: CV overrides knob when connected
let depth = if let Some(cv) = depth_cv {
let cv_val = cv.get(frame).copied().unwrap_or(f32::NAN);
if cv_val.is_nan() {
self.depth
} else {
cv_val.clamp(0.0, 1.0)
}
} else {
self.depth
};
// Determine modulation value (0..1 range, pre-depth)
let mod_value = if let Some(cv) = mod_cv {
let cv_val = cv.get(frame).copied().unwrap_or(f32::NAN);
if cv_val.is_nan() {
// No external mod — use internal LFO
None
} else {
Some(cv_val.clamp(0.0, 1.0))
}
} else {
None
};
let modulation = if let Some(ext) = mod_value {
// External modulation: CV value scaled by depth
ext * depth
} else {
// Internal LFO: resolve rate with CV
let rate = if let Some(cv) = rate_cv {
let cv_val = cv.get(frame).copied().unwrap_or(f32::NAN);
if cv_val.is_nan() {
self.rate
} else {
(self.rate + cv_val * 14.0).clamp(0.1, 14.0)
}
} else {
self.rate
};
let lfo_value = (self.lfo_phase * 2.0 * PI).sin() * 0.5 + 0.5;
self.lfo_phase += rate / self.sample_rate as f32;
if self.lfo_phase >= 1.0 {
self.lfo_phase -= 1.0;
}
lfo_value * depth
};
let delay_samples = base_delay_samples + modulation * max_modulation_samples;
// 100% wet — output is only the delayed signal
output[frame * 2] = self.read_interpolated_sample(&self.delay_buffer_left, delay_samples);
output[frame * 2 + 1] = self.read_interpolated_sample(&self.delay_buffer_right, delay_samples);
self.delay_buffer_left[self.write_position] = left_in;
self.delay_buffer_right[self.write_position] = right_in;
self.write_position = (self.write_position + 1) % self.max_delay_samples;
}
}
fn reset(&mut self) {
self.delay_buffer_left.fill(0.0);
self.delay_buffer_right.fill(0.0);
self.write_position = 0;
self.lfo_phase = 0.0;
}
fn node_type(&self) -> &str {
"Vibrato"
}
fn name(&self) -> &str {
&self.name
}
fn clone_node(&self) -> Box<dyn AudioNode> {
Box::new(Self {
name: self.name.clone(),
rate: self.rate,
depth: self.depth,
delay_buffer_left: vec![0.0; self.max_delay_samples],
delay_buffer_right: vec![0.0; self.max_delay_samples],
write_position: 0,
max_delay_samples: self.max_delay_samples,
sample_rate: self.sample_rate,
lfo_phase: 0.0,
inputs: self.inputs.clone(),
outputs: self.outputs.clone(),
parameters: self.parameters.clone(),
})
}
fn as_any_mut(&mut self) -> &mut dyn std::any::Any {
self
}
fn as_any(&self) -> &dyn std::any::Any {
self
}
}