filther
a custom designed filthy lowpass filter with resonance-brightness "cut" controls the filtering of the increase/decrease for the linear filter, causing a frequency-controlled linear smoothing of the signal, but also inducing a raw resonance. "max" sets a maximum to the linear changing rate, causing an extra linear lowpass filtering of the input signal and resonance. "darkness" feeds back the output to the input of the filter. notice though, that due to the design of the filter, there's always resonance and the resonance knob just fades between bright and dark resonance.
Inlets
frac32buffer lp
frac32buffer hp
frac32 cut
Outlets
frac32buffer out
Parameters
frac32.s.map sets modulation width of the cut-input
frac32.s.map controls character of resonance
frac32.u.map sets maximum changerate: linear filter
frac32.s.map.pitch sets cutoff frequency
int32_t prev;
int32_t get;
int32_t cnt;
int32_t val1;
int32_t val2;
int32_t filter;
int32_t increase;
int32_t Increase;
int32_t max;int32_t f;
MTOF(param_cut + ___SMMUL(param_extCut << 4, inlet_cut << 2), f)
max = (param_max >> 4) + (1 << 17);int32_t in = inlet_lp + inlet_hp +
___SMMUL(param_darkness << 2, (filter - inlet_hp) << 2);
cnt += 1;
if (!(prev == in)) {
val2 = val1;
val1 = in;
get = cnt;
cnt = 0;
}
increase = (val1 - val2) / get;
increase = increase > 0 ? increase : -increase;
increase = increase > max ? max : increase;
int32_t Filter = in > filter ? increase : -increase;
Increase = ___SMMLA((Filter - Increase) << 1, f, Increase);
filter = filter + Increase;
outlet_out = filter - inlet_hp;
prev = in;