#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; }