You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
OpenAudio_ArduinoLibrary/synth_waveform_F32.cpp

92 lines
2.3 KiB

#include <arm_math.h>
#include "synth_waveform_F32.h"
void AudioSynthWaveform_F32::update(void) {
audio_block_f32_t *block, *lfo;
if (_magnitude == 0.0f) return;
block = allocate_f32();
if (!block) return;
lfo = receiveReadOnly_f32(0);
switch (_OscillatorMode) {
case OSCILLATOR_MODE_SINE:
for (int i = 0; i < AUDIO_BLOCK_SAMPLES; i++) {
applyMod(i, lfo);
block->data[i] = arm_sin_f32(_Phase);
_Phase += _PhaseIncrement;
while (_Phase >= twoPI) {
_Phase -= twoPI;
}
}
break;
case OSCILLATOR_MODE_SAW:
for (int i = 0; i < AUDIO_BLOCK_SAMPLES; i++) {
applyMod(i, lfo);
block->data[i] = 1.0f - (2.0f * _Phase / twoPI);
_Phase += _PhaseIncrement;
while (_Phase >= twoPI) {
_Phase -= twoPI;
}
}
break;
case OSCILLATOR_MODE_SQUARE:
for (int i = 0; i < AUDIO_BLOCK_SAMPLES; i++) {
applyMod(i, lfo);
if (_Phase <= _PI) {
block->data[i] = 1.0f;
} else {
block->data[i] = -1.0f;
}
_Phase += _PhaseIncrement;
while (_Phase >= twoPI) {
_Phase -= twoPI;
}
}
break;
case OSCILLATOR_MODE_TRIANGLE:
for (int i = 0; i < AUDIO_BLOCK_SAMPLES; i++) {
applyMod(i, lfo);
float32_t value = -1.0f + (2.0f * _Phase / twoPI);
block->data[i] = 2.0f * (fabs(value) - 0.5f);
_Phase += _PhaseIncrement;
while (_Phase >= twoPI) {
_Phase -= twoPI;
}
}
break;
}
if (_magnitude != 1.0f) {
arm_scale_f32(block->data, _magnitude, block->data, AUDIO_BLOCK_SAMPLES);
}
if (lfo) {
release(lfo);
}
AudioStream_F32::transmit(block);
AudioStream_F32::release(block);
}
inline float32_t AudioSynthWaveform_F32::applyMod(uint32_t sample, audio_block_f32_t *lfo) {
if (_PortamentoSamples > 0 && _CurrentPortamentoSample++ < _PortamentoSamples) {
_Frequency+=_PortamentoIncrement;
}
float32_t osc_frequency = _Frequency;
if (lfo && _PitchModAmt > 0.0f) {
osc_frequency = _Frequency * powf(2.0f, 0.0f / 1200.0f + lfo->data[sample] * _PitchModAmt);
}
_PhaseIncrement = osc_frequency * twoPI / AUDIO_SAMPLE_RATE_EXACT;
return osc_frequency;
}