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

146 lines
3.4 KiB
Rust

use crate::audio::node_graph::{AudioNode, NodeCategory, NodePort, Parameter, SignalType};
use crate::audio::midi::MidiEvent;
/// Sample & Hold - samples input CV when triggered by a gate signal
/// Classic modular synth utility for creating stepped sequences
pub struct SampleHoldNode {
name: String,
held_value: f32,
last_gate: f32,
inputs: Vec<NodePort>,
outputs: Vec<NodePort>,
parameters: Vec<Parameter>,
}
impl SampleHoldNode {
pub fn new(name: impl Into<String>) -> Self {
let name = name.into();
let inputs = vec![
NodePort::new("CV In", SignalType::CV, 0),
NodePort::new("Gate In", SignalType::CV, 1),
];
let outputs = vec![
NodePort::new("CV Out", SignalType::CV, 0),
];
let parameters = vec![];
Self {
name,
held_value: 0.0,
last_gate: 0.0,
inputs,
outputs,
parameters,
}
}
}
impl AudioNode for SampleHoldNode {
fn category(&self) -> NodeCategory {
NodeCategory::Utility
}
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) {
// No parameters
}
fn get_parameter(&self, _id: u32) -> f32 {
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 outputs.is_empty() {
return;
}
let output = &mut outputs[0];
let length = output.len();
// Get CV input
let cv_input = if !inputs.is_empty() && !inputs[0].is_empty() {
inputs[0]
} else {
&[]
};
// Get Gate input
let gate_input = if inputs.len() > 1 && !inputs[1].is_empty() {
inputs[1]
} else {
&[]
};
// Process each sample
for i in 0..length {
let cv = if i < cv_input.len() { cv_input[i] } else { 0.0 };
let gate = if i < gate_input.len() { gate_input[i] } else { 0.0 };
// Detect rising edge (trigger)
let gate_active = gate > 0.5;
let last_gate_active = self.last_gate > 0.5;
if gate_active && !last_gate_active {
// Rising edge detected - sample the input
self.held_value = cv;
}
self.last_gate = gate;
output[i] = self.held_value;
}
}
fn reset(&mut self) {
self.held_value = 0.0;
self.last_gate = 0.0;
}
fn node_type(&self) -> &str {
"SampleHold"
}
fn name(&self) -> &str {
&self.name
}
fn clone_node(&self) -> Box<dyn AudioNode> {
Box::new(Self {
name: self.name.clone(),
held_value: self.held_value,
last_gate: self.last_gate,
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
}
}