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

154 lines
4.1 KiB
Rust

use crate::audio::node_graph::{AudioNode, NodeCategory, NodePort, Parameter, ParameterUnit, SignalType};
use crate::audio::midi::MidiEvent;
const PARAM_GAIN_1: u32 = 0;
const PARAM_GAIN_2: u32 = 1;
const PARAM_GAIN_3: u32 = 2;
const PARAM_GAIN_4: u32 = 3;
/// Mixer node - combines multiple audio inputs with independent gain controls
pub struct MixerNode {
name: String,
gains: [f32; 4],
inputs: Vec<NodePort>,
outputs: Vec<NodePort>,
parameters: Vec<Parameter>,
}
impl MixerNode {
pub fn new(name: impl Into<String>) -> Self {
let name = name.into();
let inputs = vec![
NodePort::new("Input 1", SignalType::Audio, 0),
NodePort::new("Input 2", SignalType::Audio, 1),
NodePort::new("Input 3", SignalType::Audio, 2),
NodePort::new("Input 4", SignalType::Audio, 3),
];
let outputs = vec![
NodePort::new("Mixed Out", SignalType::Audio, 0),
];
let parameters = vec![
Parameter::new(PARAM_GAIN_1, "Gain 1", 0.0, 2.0, 1.0, ParameterUnit::Generic),
Parameter::new(PARAM_GAIN_2, "Gain 2", 0.0, 2.0, 1.0, ParameterUnit::Generic),
Parameter::new(PARAM_GAIN_3, "Gain 3", 0.0, 2.0, 1.0, ParameterUnit::Generic),
Parameter::new(PARAM_GAIN_4, "Gain 4", 0.0, 2.0, 1.0, ParameterUnit::Generic),
];
Self {
name,
gains: [1.0, 1.0, 1.0, 1.0],
inputs,
outputs,
parameters,
}
}
}
impl AudioNode for MixerNode {
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) {
match id {
PARAM_GAIN_1 => self.gains[0] = value.clamp(0.0, 2.0),
PARAM_GAIN_2 => self.gains[1] = value.clamp(0.0, 2.0),
PARAM_GAIN_3 => self.gains[2] = value.clamp(0.0, 2.0),
PARAM_GAIN_4 => self.gains[3] = value.clamp(0.0, 2.0),
_ => {}
}
}
fn get_parameter(&self, id: u32) -> f32 {
match id {
PARAM_GAIN_1 => self.gains[0],
PARAM_GAIN_2 => self.gains[1],
PARAM_GAIN_3 => self.gains[2],
PARAM_GAIN_4 => self.gains[3],
_ => 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];
// Audio signals are stereo (interleaved L/R)
let frames = output.len() / 2;
// Clear output buffer first
output.fill(0.0);
// Mix each input with its gain
for (input_idx, input) in inputs.iter().enumerate().take(4) {
if input_idx >= self.gains.len() {
break;
}
let gain = self.gains[input_idx];
let input_frames = input.len() / 2;
let process_frames = frames.min(input_frames);
for frame in 0..process_frames {
output[frame * 2] += input[frame * 2] * gain; // Left
output[frame * 2 + 1] += input[frame * 2 + 1] * gain; // Right
}
}
}
fn reset(&mut self) {
// No state to reset
}
fn node_type(&self) -> &str {
"Mixer"
}
fn name(&self) -> &str {
&self.name
}
fn clone_node(&self) -> Box<dyn AudioNode> {
Box::new(Self {
name: self.name.clone(),
gains: self.gains,
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
}
}