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- #include "voices.h"
- #include "audio.h"
- #include "stdlib.h"
-
- // these are imported from audio.c
- extern uint16_t envelope_index;
- extern float note_timbre;
- extern float polyphony_rate;
-
- voice_type voice = default_voice;
-
- void set_voice(voice_type v) {
- voice = v;
- }
-
- void voice_iterate() {
- voice = (voice + 1) % number_of_voices;
- }
-
- void voice_deiterate() {
- voice = (voice - 1) % number_of_voices;
- }
-
- float voice_envelope(float frequency) {
- // envelope_index ranges from 0 to 0xFFFF, which is preserved at 880.0 Hz
- uint16_t compensated_index = (uint16_t)((float)envelope_index * (880.0 / frequency));
-
- switch (voice) {
- case default_voice:
- note_timbre = TIMBRE_50;
- polyphony_rate = 0;
- break;
-
- case butts_fader:
- polyphony_rate = 0;
- 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 = .125 - pow(((float)compensated_index - 20) / (200 - 20), 2)*.125;
- break;
-
- default:
- note_timbre = 0;
- break;
- }
- break;
-
- // case octave_crunch:
- // polyphony_rate = 0;
- // 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
- polyphony_rate = 0;
- 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 = (float)abs((compensated_index*OCS_SPEED % 3000) - 1500) * ( OCS_AMP / 1500 ) + (1 - OCS_AMP) / 2;
- break;
- }
- break;
-
- case duty_octave_down:
- polyphony_rate = 0;
- note_timbre = (envelope_index % 2) * .125 + .375 * 2;
- if ((envelope_index % 4) == 0)
- note_timbre = 0.5;
- if ((envelope_index % 8) == 0)
- note_timbre = 0;
- break;
- case delayed_vibrato:
- polyphony_rate = 0;
- note_timbre = TIMBRE_50;
- #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 delayed_vibrato_octave:
- // polyphony_rate = 0;
- // if ((envelope_index % 2) == 1) {
- // note_timbre = 0.55;
- // } else {
- // note_timbre = 0.45;
- // }
- // #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 = 0.5;
- // if ((envelope_index % 3) == 0)
- // note_timbre = 0.75;
- // break;
- // case duty_fourth_down:
- // note_timbre = 0.0;
- // if ((envelope_index % 12) == 0)
- // note_timbre = 0.75;
- // if (((envelope_index % 12) % 4) != 1)
- // note_timbre = 0.75;
- // break;
- // case duty_third_down:
- // note_timbre = 0.5;
- // if ((envelope_index % 5) == 0)
- // note_timbre = 0.75;
- // break;
- // case duty_fifth_third_down:
- // note_timbre = 0.5;
- // if ((envelope_index % 5) == 0)
- // note_timbre = 0.75;
- // if ((envelope_index % 3) == 0)
- // note_timbre = 0.25;
- // break;
-
- default:
- break;
- }
-
- return frequency;
- }
-
-
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