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.h

146 lines
4.0 KiB

/*
* AudioSynthWaveform_F32
*
* Created: Patrick Radius, January 2017
* Purpose: Generate waveforms at a given frequency and amplitude. Allows for pitch-modulation and portamento.
*
* This processes a single stream fo audio data (ie, it is mono)
*
* MIT License. use at your own risk.
*/
#ifndef SYNTHWAVEFORMF32_H
#define SYNTHWAVEFORMF32_H
#include <arm_math.h>
#include <AudioStream_F32.h>
class AudioSynthWaveform_F32 : public AudioStream_F32
{
//GUI: inputs:0, outputs:1 //this line used for automatic generation of GUI node
public:
enum OscillatorMode {
OSCILLATOR_MODE_SINE = 0,
OSCILLATOR_MODE_SAW,
OSCILLATOR_MODE_SQUARE,
OSCILLATOR_MODE_TRIANGLE
};
AudioSynthWaveform_F32(const AudioSettings_F32 &settings) : AudioStream_F32(1, inputQueueArray_f32),
_PI(2*acos(0.0f)),
twoPI(2 * _PI),
sample_rate_Hz(AUDIO_SAMPLE_RATE_EXACT),
_OscillatorMode(OSCILLATOR_MODE_SINE),
_Frequency(440.0f),
_Phase(0.0f),
_PhaseIncrement(0.0f),
_PitchModAmt(0.0f),
_PortamentoIncrement(0.0f),
_PortamentoSamples(0),
_CurrentPortamentoSample(0),
_NotesPlaying(0)
{
setSampleRate(settings.sample_rate_Hz);
}
AudioSynthWaveform_F32(void) : AudioStream_F32(1, inputQueueArray_f32), //uses default AUDIO_SAMPLE_RATE from AudioStream.h
_PI(2*acos(0.0f)),
twoPI(2 * _PI),
sample_rate_Hz(AUDIO_SAMPLE_RATE_EXACT),
_OscillatorMode(OSCILLATOR_MODE_SINE),
_Frequency(440.0f),
_Phase(0.0f),
_PhaseIncrement(0.0f),
_PitchModAmt(0.0f),
_PortamentoIncrement(0.0f),
_PortamentoSamples(0),
_CurrentPortamentoSample(0),
_NotesPlaying(0) {};
void frequency(float32_t freq) {
float32_t nyquist = sample_rate_Hz/2.f;
if (freq < 0.0) freq = 0.0;
else if (freq > nyquist) freq = nyquist;
if (_PortamentoSamples > 0 && _NotesPlaying > 0) {
_PortamentoIncrement = (freq - _Frequency) / (float32_t)_PortamentoSamples;
_CurrentPortamentoSample = 0;
} else {
_Frequency = freq;
}
_PhaseIncrement = _Frequency * twoPI / sample_rate_Hz;
}
void amplitude(float32_t n) {
if (n < 0) n = 0;
_magnitude = n;
}
void begin(short t_type) {
_Phase = 0;
oscillatorMode(t_type);
}
void begin(float32_t t_amp, float32_t t_freq, short t_type) {
amplitude(t_amp);
frequency(t_freq);
begin(t_type);
}
void pitchModAmount(float32_t amount) {
_PitchModAmt = amount;
}
void oscillatorMode(int mode) {
_OscillatorMode = (OscillatorMode)mode;
}
void portamentoTime(float32_t slidetime) {
_PortamentoTime = slidetime;
_PortamentoSamples = floorf(slidetime * sample_rate_Hz);
}
void onNoteOn() {
_NotesPlaying++;
}
void onNoteOff() {
if (_NotesPlaying > 0) {
_NotesPlaying--;
}
}
void update(void);
void setSampleRate(const float32_t fs_Hz)
{
_PhaseIncrement = _PhaseIncrement*sample_rate_Hz / fs_Hz;
_PortamentoSamples = floorf( ((float)_PortamentoSamples) * fs_Hz / sample_rate_Hz );
sample_rate_Hz = fs_Hz;
}
private:
inline float32_t applyMod(uint32_t sample, audio_block_f32_t *lfo);
const float32_t _PI;
float32_t twoPI;
float32_t sample_rate_Hz;
OscillatorMode _OscillatorMode;
float32_t _Frequency;
float32_t _Phase;
float32_t _PhaseIncrement;
float32_t _magnitude;
float32_t _PitchModAmt;
float32_t _PortamentoTime;
float32_t _PortamentoIncrement;
uint64_t _PortamentoSamples;
uint64_t _CurrentPortamentoSample;
uint8_t _NotesPlaying;
audio_block_f32_t *inputQueueArray_f32[1];
};
#endif