Files
metabalus/src/synth/Voice.cpp
2026-01-17 15:56:39 -06:00

108 lines
3.7 KiB
C++

#include "Voice.h"
#include <cmath>
#include <iostream>
Voice::Voice(SmoothedParam* params, WavetableController* wavetable) : params_(params), wavetable_(wavetable) {
oscillators_.fill(Oscillator(wavetable_));
}
// cascade sample rate to all descendant objects
void Voice::setSampleRate(float sampleRate) {
sampleRate_ = sampleRate;
// foreach envelope...
gainEnvelope_.setSampleRate(sampleRate);
cutoffEnvelope_.setSampleRate(sampleRate);
resonanceEnvelope_.setSampleRate(sampleRate);
// foreach filter...
filter1_.setSampleRate(sampleRate);
filter2_.setSampleRate(sampleRate);
// then foreach oscillator
for(Oscillator& o : oscillators_) {
o.setSampleRate(sampleRate);
}
}
inline float Voice::getParam(ParamId id) {
return params_[static_cast<size_t>(id)].current;
}
void Voice::noteOn(int midiNote, float velocity) {
note_ = midiNote;
velocity_ = velocity;
active_ = true;
// TODO: for each envelope ...
gainEnvelope_.noteOn();
cutoffEnvelope_.noteOn();
resonanceEnvelope_.noteOn();
}
void Voice::noteOff() {
// again, foreach
gainEnvelope_.noteOff();
cutoffEnvelope_.noteOff();
resonanceEnvelope_.noteOff();
active_ = false;
}
bool Voice::isActive() {
return active_;
}
// generates a single sample, called from synth.process()
float Voice::process(float* params, bool& scopeTrigger) {
// process all envelopes
// should be easy enough if all the envelopes are in an array to loop over them
gainEnvelope_.set(getParam(ParamId::Osc1VolumeEnvA), getParam(ParamId::Osc1VolumeEnvD), getParam(ParamId::Osc1VolumeEnvS), getParam(ParamId::Osc1VolumeEnvR));
cutoffEnvelope_.set(getParam(ParamId::FilterCutoffEnvA), getParam(ParamId::FilterCutoffEnvD), getParam(ParamId::FilterCutoffEnvS), getParam(ParamId::FilterCutoffEnvR));
resonanceEnvelope_.set(getParam(ParamId::FilterResonanceEnvA), getParam(ParamId::FilterResonanceEnvD), getParam(ParamId::FilterResonanceEnvS), getParam(ParamId::FilterResonanceEnvR));
// skip if no active notes
if(!gainEnvelope_.isActive()) {
return 0.0f;
}
// process all envelopes
float gainEnv = gainEnvelope_.process();
float cutoffEnv = cutoffEnvelope_.process();
float resonanceEnv = resonanceEnvelope_.process();
// calculate the change that the velocity will make
// TODO: make velocity parameters configurable, probably also for filterCutoff and filterResonance
float velocityGain = std::lerp(velocityCenter, velocity_, velocitySensitivity);
float gain = gainEnv * getParam(ParamId::Osc1VolumeDepth) * velocityGain;
// sample generation
uint8_t osc1Wave = (static_cast<uint8_t>(std::round(getParam(ParamId::Osc1WaveSelector1))));
for(Oscillator& o : oscillators_) {
o.setWavetable(osc1Wave);
}
// TODO: oscillator pitch offset
bool temp = false;
float osc1 = oscillators_[0].process(note_, scopeTrigger);
float osc2 = oscillators_[1].process(static_cast<uint8_t>(note_+12), temp);
float osc3 = oscillators_[2].process(static_cast<uint8_t>(note_+19), temp);
float sampleOut = (osc1 + osc2*0.5f + osc3*0.25f) * gain;
// filter sample
float baseFreq = oscillators_[0].frequency();
float cutoffFreq = cutoffEnv * pow(2.0f, getParam(ParamId::FilterCutoffDepth)) * baseFreq * velocityGain;
float resonance = resonanceEnv * getParam(ParamId::FilterResonanceDepth) * velocityGain;
filter1_.setParams(Filter::Type::BiquadLowpass, cutoffFreq, resonance);
filter2_.setParams(Filter::Type::BiquadLowpass, cutoffFreq, resonance);
sampleOut = filter1_.biquadProcess(sampleOut);
sampleOut = filter2_.biquadProcess(sampleOut);
return sampleOut;
}