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synthio: remove more dead code

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Jeff Epler 2023-05-16 10:07:22 -05:00
parent b2c6f9b1a4
commit e6c5e83a45
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1 changed files with 0 additions and 50 deletions
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shared-module/synthio/__init__.c
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@ -40,9 +40,6 @@ STATIC const int16_t square_wave[] = {-32768, 32767};
STATIC const uint16_t notes[] = {8372, 8870, 9397, 9956, 10548, 11175, 11840,
12544, 13290, 14080, 14917, 15804}; // 9th octave
STATIC int32_t round_float_to_int(mp_float_t f) {
return (int32_t)(f + MICROPY_FLOAT_CONST(0.5));
}
STATIC int64_t round_float_to_int64(mp_float_t f) {
return (int64_t)(f + MICROPY_FLOAT_CONST(0.5));
@ -546,53 +543,6 @@ uint32_t synthio_frequency_convert_scaled_to_dds(uint64_t frequency_scaled, int3
return (sample_rate / 2 + frequency_scaled) / sample_rate;
}
void synthio_lfo_set(synthio_lfo_state_t *state, const synthio_lfo_descr_t *descr, uint32_t sample_rate) {
state->amplitude_scaled = round_float_to_int(descr->amplitude * 32768);
state->dds = synthio_frequency_convert_float_to_dds(descr->frequency * 65536, sample_rate);
}
STATIC int synthio_lfo_step_common(synthio_lfo_state_t *state, uint16_t dur) {
uint32_t phase = state->phase;
uint16_t whole_phase = phase >> 16;
// advance the phase accumulator
state->phase = phase + state->dds * dur;
return whole_phase;
}
STATIC int synthio_lfo_sweep_common(synthio_lfo_state_t *state, uint16_t dur) {
uint32_t old_phase = state->phase;
uint16_t whole_phase = synthio_lfo_step_common(state, dur);
if (state->phase < old_phase) {
state->phase = 0xffffffff;
}
return whole_phase;
}
int synthio_sweep_step(synthio_lfo_state_t *state, uint16_t dur) {
uint16_t whole_phase = synthio_lfo_sweep_common(state, dur);
return (state->amplitude_scaled * whole_phase) / 65536 + state->offset_scaled;
}
int synthio_sweep_in_step(synthio_lfo_state_t *state, uint16_t dur) {
uint16_t whole_phase = 65535 - synthio_lfo_sweep_common(state, dur);
return (state->amplitude_scaled * whole_phase) / 65536 + state->offset_scaled;
}
int synthio_lfo_step(synthio_lfo_state_t *state, uint16_t dur) {
uint16_t whole_phase = synthio_lfo_step_common(state, dur);
// create a triangle wave, it's quick and easy
int v;
if (whole_phase < 16384) { // ramp from 0 to amplitude
v = (state->amplitude_scaled * whole_phase);
} else if (whole_phase < 49152) { // ramp from +amplitude to -amplitude
v = (state->amplitude_scaled * (32768 - whole_phase));
} else { // from -amplitude to 0
v = (state->amplitude_scaled * (whole_phase - 65536));
}
return v / 16384 + state->offset_scaled;
}
void shared_bindings_synthio_lfo_tick(uint32_t sample_rate) {
synthio_global_rate_scale = (mp_float_t)SYNTHIO_MAX_DUR / sample_rate;
synthio_global_tick++;