slider1:1<0.01,10,0.01>Gain
slider2:1<0,1,0.01>Mix
slider3:1<0,1,0.01>Output
slider4:25<20,250,5>Size (ms)

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

@init
function expdist(k,gain,mix) (
q0=k*gain;
z0=sign(q0)*(1-exp(-abs(q0)));
y0=mix*z0+(1-mix)*k;
);

function expdist2(x,gain,mix) (
q1=x*gain;
z1=sign(q1)*(1-exp(-abs(q1)));
y1=mix*z1+(1-mix)*x;
);

histbuf=1000000;
histpos=0;

@slider
gain=slider1;
mix=slider2;
output=slider3;

size=slider4;
histsize=size/1000*srate|0;

@sample
in0=spl0;
in1=spl1;

spl0=expdist(in0,gain,mix);
spl1=expdist(in1,gain,mix);

spl0*=output;
spl1*=output;

histbuf[histpos]=spl0;
histbuf[histpos+histsize]=spl1;

histpos+=1;
histpos >= histsize ? histpos=0;

@gfx 0 101
gfxSize=min(gfx_w,gfx_h);

gfx_r=gfx_g=gfx_b=0; gfx_a=1;
gfx_x=gfx_y=0;
gfx_rectto(gfx_w,gfx_h);

gfx_r=gfx_g=gfx_b=0.8; gfx_a=1;
gfx_x=gfxSize/2;
gfx_y=0;
gfx_lineto(gfxSize/2,gfxSize,0);
gfx_x=0;
gfx_y=gfxSize/2;
gfx_lineto(gfxSize,gfxSize/2,0);

gfx_r=0.5; gfx_g=1; gfx_b=0; gfx_a=1;
gfx_x=0;
gfx_y=gfxSize;
x = -1;
while(
y = -expdist2(x,gain,mix);
gfx_lineto(x*gfxSize/2+gfxSize/2,y*gfxSize/2+gfxSize/2,1);
(x+=0.001) <= 1;
);
gfx_lineto(gfxSize-1,0,1);

offs=histpos;
gscale=gfxSize/histsize;
gbuf=histbuf;
gscale2=gfxSize/2;

gfx_r=0; gfx_g=1; gfx_b=1; gfx_a=0.5;

ga=0;
loop(histsize,
gv=gbuf[offs];
offs+=1;
offs>=histsize?offs=0;
gx=ga*gscale;
gy=gfxSize/2 - gv*gscale2;
ga ? gfx_lineto(gx,gy,0) : ( gfx_x=gx; gfx_y=gy; );
ga+=1;
);

gbuf+=histsize;
