desc: One pole LP and HP

slider1:200<20,22000,1>Frequency (Hz)
slider2:0<0,1,1{lowpass,highpass}>Mode
slider3:0<-24,24,0.1>Output (dB)

in_pin:L in
in_pin:R in
out_pin:L out
out_pin:R out

@slider
x = 2*$pi*slider1/srate;
p = (2-cos(x)) - sqrt((2-cos(x))^2 - 1);
//p = (1 - 2*slider1/srate)^2;

gain=10^(slider3/20);

@sample
inA=spl0;
inB=spl1;

slider2==1?
(
tmpA = (1-p)*inA + p*tmpA;
tmpB = (1-p)*inB + p*tmpB;
spl0=(inA-tmpA)*gain;
spl1=(inB-tmpB)*gain;
):(
tmpA = (1-p)*inA + p*tmpA;
tmpB = (1-p)*inB + p*tmpB;
spl0=tmpA*gain;
spl1=tmpB*gain;
);
