qmk-firmware/quantum/audio/voices.c
2016-04-21 00:37:45 -04:00

60 lines
1.5 KiB
C

#include "voices.h"
extern uint16_t envelope_index;
extern float note_timbre;
voice_type voice = default_voice;
void set_voice(voice_type v) {
voice = v;
}
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:
// nothing here on purpose
break;
case butts_fader:
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:
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;
}
return frequency;
}