diff options
Diffstat (limited to 'quantum/audio/voices.c')
| -rw-r--r-- | quantum/audio/voices.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/quantum/audio/voices.c b/quantum/audio/voices.c new file mode 100644 index 000000000..6d4172a06 --- /dev/null +++ b/quantum/audio/voices.c @@ -0,0 +1,165 @@ +#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; +} + + |