365 lines
12 KiB
C
365 lines
12 KiB
C
/* Copyright 2016 Jack Humbert
|
|
* Copyright 2020 JohSchneider
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
#include "voices.h"
|
|
#include "audio.h"
|
|
#include "timer.h"
|
|
#include <stdlib.h>
|
|
#include <math.h>
|
|
|
|
uint8_t note_timbre = TIMBRE_DEFAULT;
|
|
bool glissando = false;
|
|
bool vibrato = false;
|
|
float vibrato_strength = 0.5;
|
|
float vibrato_rate = 0.125;
|
|
|
|
uint16_t voices_timer = 0;
|
|
|
|
#ifdef AUDIO_VOICE_DEFAULT
|
|
voice_type voice = AUDIO_VOICE_DEFAULT;
|
|
#else
|
|
voice_type voice = default_voice;
|
|
#endif
|
|
|
|
void set_voice(voice_type v) {
|
|
voice = v;
|
|
}
|
|
|
|
void voice_iterate(void) {
|
|
voice = (voice + 1) % number_of_voices;
|
|
}
|
|
|
|
void voice_deiterate(void) {
|
|
voice = (voice - 1 + number_of_voices) % number_of_voices;
|
|
}
|
|
|
|
#ifdef AUDIO_VOICES
|
|
float mod(float a, int b) {
|
|
float r = fmod(a, b);
|
|
return r < 0 ? r + b : r;
|
|
}
|
|
|
|
// Effect: 'vibrate' a given target frequency slightly above/below its initial value
|
|
float voice_add_vibrato(float average_freq) {
|
|
float vibrato_counter = mod(timer_read() / (100 * vibrato_rate), VIBRATO_LUT_LENGTH);
|
|
|
|
return average_freq * pow(vibrato_lut[(int)vibrato_counter], vibrato_strength);
|
|
}
|
|
|
|
// Effect: 'slides' the 'frequency' from the starting-point, to the target frequency
|
|
float voice_add_glissando(float from_freq, float to_freq) {
|
|
if (to_freq != 0 && from_freq < to_freq && from_freq < to_freq * pow(2, -440 / to_freq / 12 / 2)) {
|
|
return from_freq * pow(2, 440 / from_freq / 12 / 2);
|
|
} else if (to_freq != 0 && from_freq > to_freq && from_freq > to_freq * pow(2, 440 / to_freq / 12 / 2)) {
|
|
return from_freq * pow(2, -440 / from_freq / 12 / 2);
|
|
} else {
|
|
return to_freq;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
float voice_envelope(float frequency) {
|
|
// envelope_index ranges from 0 to 0xFFFF, which is preserved at 880.0 Hz
|
|
// __attribute__((unused)) uint16_t compensated_index = (uint16_t)((float)envelope_index * (880.0 / frequency));
|
|
#ifdef AUDIO_VOICES
|
|
uint16_t envelope_index = timer_elapsed(voices_timer); // TODO: multiply in some factor?
|
|
uint16_t compensated_index = envelope_index / 100; // TODO: correct factor would be?
|
|
#endif
|
|
|
|
switch (voice) {
|
|
case default_voice:
|
|
glissando = false;
|
|
// note_timbre = TIMBRE_50; //Note: leave the user the possibility to adjust the timbre with 'audio_set_timbre'
|
|
break;
|
|
|
|
#ifdef AUDIO_VOICES
|
|
|
|
case vibrating:
|
|
glissando = false;
|
|
vibrato = true;
|
|
break;
|
|
|
|
case something:
|
|
glissando = false;
|
|
switch (compensated_index) {
|
|
case 0 ... 9:
|
|
note_timbre = TIMBRE_12;
|
|
break;
|
|
|
|
case 10 ... 19:
|
|
note_timbre = TIMBRE_25;
|
|
break;
|
|
|
|
case 20 ... 200:
|
|
note_timbre = 12 + 12;
|
|
break;
|
|
|
|
default:
|
|
note_timbre = 12;
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case drums:
|
|
glissando = false;
|
|
// switch (compensated_index) {
|
|
// case 0 ... 10:
|
|
// note_timbre = 50;
|
|
// break;
|
|
// case 11 ... 20:
|
|
// note_timbre = 50 * (21 - compensated_index) / 10;
|
|
// break;
|
|
// default:
|
|
// note_timbre = 0;
|
|
// break;
|
|
// }
|
|
// frequency = (rand() % (int)(frequency * 1.2 - frequency)) + (frequency * 0.8);
|
|
|
|
if (frequency < 80.0) {
|
|
} else if (frequency < 160.0) {
|
|
// Bass drum: 60 - 100 Hz
|
|
frequency = (rand() % (int)(40)) + 60;
|
|
switch (envelope_index) {
|
|
case 0 ... 10:
|
|
note_timbre = 50;
|
|
break;
|
|
case 11 ... 20:
|
|
note_timbre = 50 * (21 - envelope_index) / 10;
|
|
break;
|
|
default:
|
|
note_timbre = 0;
|
|
break;
|
|
}
|
|
|
|
} else if (frequency < 320.0) {
|
|
// Snare drum: 1 - 2 KHz
|
|
frequency = (rand() % (int)(1000)) + 1000;
|
|
switch (envelope_index) {
|
|
case 0 ... 5:
|
|
note_timbre = 50;
|
|
break;
|
|
case 6 ... 20:
|
|
note_timbre = 50 * (21 - envelope_index) / 15;
|
|
break;
|
|
default:
|
|
note_timbre = 0;
|
|
break;
|
|
}
|
|
|
|
} else if (frequency < 640.0) {
|
|
// Closed Hi-hat: 3 - 5 KHz
|
|
frequency = (rand() % (int)(2000)) + 3000;
|
|
switch (envelope_index) {
|
|
case 0 ... 15:
|
|
note_timbre = 50;
|
|
break;
|
|
case 16 ... 20:
|
|
note_timbre = 50 * (21 - envelope_index) / 5;
|
|
break;
|
|
default:
|
|
note_timbre = 0;
|
|
break;
|
|
}
|
|
|
|
} else if (frequency < 1280.0) {
|
|
// Open Hi-hat: 3 - 5 KHz
|
|
frequency = (rand() % (int)(2000)) + 3000;
|
|
switch (envelope_index) {
|
|
case 0 ... 35:
|
|
note_timbre = 50;
|
|
break;
|
|
case 36 ... 50:
|
|
note_timbre = 50 * (51 - envelope_index) / 15;
|
|
break;
|
|
default:
|
|
note_timbre = 0;
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
case butts_fader:
|
|
glissando = true;
|
|
switch (compensated_index) {
|
|
case 0 ... 9:
|
|
frequency = frequency / 4;
|
|
note_timbre = TIMBRE_12;
|
|
break;
|
|
|
|
case 10 ... 19:
|
|
frequency = frequency / 2;
|
|
note_timbre = TIMBRE_12;
|
|
break;
|
|
|
|
case 20 ... 200:
|
|
note_timbre = 12 - (uint8_t)(pow(((float)compensated_index - 20) / (200 - 20), 2) * 12.5);
|
|
break;
|
|
|
|
default:
|
|
note_timbre = 0;
|
|
break;
|
|
}
|
|
break;
|
|
|
|
// case octave_crunch:
|
|
// switch (compensated_index) {
|
|
// case 0 ... 9:
|
|
// case 20 ... 24:
|
|
// case 30 ... 32:
|
|
// frequency = frequency / 2;
|
|
// note_timbre = TIMBRE_12;
|
|
// break;
|
|
|
|
// case 10 ... 19:
|
|
// case 25 ... 29:
|
|
// case 33 ... 35:
|
|
// frequency = frequency * 2;
|
|
// note_timbre = TIMBRE_12;
|
|
// break;
|
|
|
|
// default:
|
|
// note_timbre = TIMBRE_12;
|
|
// break;
|
|
// }
|
|
// break;
|
|
|
|
case duty_osc:
|
|
// This slows the loop down a substantial amount, so higher notes may freeze
|
|
glissando = true;
|
|
switch (compensated_index) {
|
|
default:
|
|
# define OCS_SPEED 10
|
|
# define OCS_AMP .25
|
|
// sine wave is slow
|
|
// note_timbre = (sin((float)compensated_index/10000*OCS_SPEED) * OCS_AMP / 2) + .5;
|
|
// triangle wave is a bit faster
|
|
note_timbre = (uint8_t)abs((compensated_index * OCS_SPEED % 3000) - 1500) * (OCS_AMP / 1500) + (1 - OCS_AMP) / 2;
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case duty_octave_down:
|
|
glissando = true;
|
|
note_timbre = (uint8_t)(100 * (envelope_index % 2) * .125 + .375 * 2);
|
|
if ((envelope_index % 4) == 0) note_timbre = 50;
|
|
if ((envelope_index % 8) == 0) note_timbre = 0;
|
|
break;
|
|
case delayed_vibrato:
|
|
glissando = true;
|
|
note_timbre = TIMBRE_50;
|
|
# define VOICE_VIBRATO_DELAY 150
|
|
# define VOICE_VIBRATO_SPEED 50
|
|
switch (compensated_index) {
|
|
case 0 ... VOICE_VIBRATO_DELAY:
|
|
break;
|
|
default:
|
|
// TODO: merge/replace with voice_add_vibrato above
|
|
frequency = frequency * vibrato_lut[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1)) / 1000 * VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
|
|
break;
|
|
}
|
|
break;
|
|
// case delayed_vibrato_octave:
|
|
// if ((envelope_index % 2) == 1) {
|
|
// note_timbre = 55;
|
|
// } else {
|
|
// note_timbre = 45;
|
|
// }
|
|
// #define VOICE_VIBRATO_DELAY 150
|
|
// #define VOICE_VIBRATO_SPEED 50
|
|
// switch (compensated_index) {
|
|
// case 0 ... VOICE_VIBRATO_DELAY:
|
|
// break;
|
|
// default:
|
|
// frequency = frequency * VIBRATO_LUT[(int)fmod((((float)compensated_index - (VOICE_VIBRATO_DELAY + 1))/1000*VOICE_VIBRATO_SPEED), VIBRATO_LUT_LENGTH)];
|
|
// break;
|
|
// }
|
|
// break;
|
|
// case duty_fifth_down:
|
|
// note_timbre = TIMBRE_50;
|
|
// if ((envelope_index % 3) == 0)
|
|
// note_timbre = TIMBRE_75;
|
|
// break;
|
|
// case duty_fourth_down:
|
|
// note_timbre = 0;
|
|
// if ((envelope_index % 12) == 0)
|
|
// note_timbre = TIMBRE_75;
|
|
// if (((envelope_index % 12) % 4) != 1)
|
|
// note_timbre = TIMBRE_75;
|
|
// break;
|
|
// case duty_third_down:
|
|
// note_timbre = TIMBRE_50;
|
|
// if ((envelope_index % 5) == 0)
|
|
// note_timbre = TIMBRE_75;
|
|
// break;
|
|
// case duty_fifth_third_down:
|
|
// note_timbre = TIMBRE_50;
|
|
// if ((envelope_index % 5) == 0)
|
|
// note_timbre = TIMBRE_75;
|
|
// if ((envelope_index % 3) == 0)
|
|
// note_timbre = TIMBRE_25;
|
|
// break;
|
|
|
|
#endif // AUDIO_VOICES
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
#ifdef AUDIO_VOICES
|
|
if (vibrato && (vibrato_strength > 0)) {
|
|
frequency = voice_add_vibrato(frequency);
|
|
}
|
|
|
|
if (glissando) {
|
|
// TODO: where to keep track of the start-frequency?
|
|
// frequency = voice_add_glissando(??, frequency);
|
|
}
|
|
#endif // AUDIO_VOICES
|
|
|
|
return frequency;
|
|
}
|
|
|
|
// Vibrato functions
|
|
|
|
void voice_set_vibrato_rate(float rate) {
|
|
vibrato_rate = rate;
|
|
}
|
|
void voice_increase_vibrato_rate(float change) {
|
|
vibrato_rate *= change;
|
|
}
|
|
void voice_decrease_vibrato_rate(float change) {
|
|
vibrato_rate /= change;
|
|
}
|
|
void voice_set_vibrato_strength(float strength) {
|
|
vibrato_strength = strength;
|
|
}
|
|
void voice_increase_vibrato_strength(float change) {
|
|
vibrato_strength *= change;
|
|
}
|
|
void voice_decrease_vibrato_strength(float change) {
|
|
vibrato_strength /= change;
|
|
}
|
|
|
|
// Timbre functions
|
|
|
|
void voice_set_timbre(uint8_t timbre) {
|
|
if ((timbre > 0) && (timbre < 100)) {
|
|
note_timbre = timbre;
|
|
}
|
|
}
|
|
uint8_t voice_get_timbre(void) {
|
|
return note_timbre;
|
|
}
|