// line noise with interpolation - http://emoc.org/hackpact/ - sep 2009

0 => int deviceNum;
Hid hi;
HidMsg msg;
if( !hi.openMouse( deviceNum ) ) me.exit();
 
Step s => dac;
.5 => s.gain;
50 => int length; // length of a segment
0 => int i;
Std.rand2f(-1,1) => float n;
Std.rand2f(-1,1) => float n1;
1::samp => dur d;
0 => int interpolation;


fun void sound() {
  while (1::samp => now) {
    if (i < length) {
      if (interpolation == 0) {
        cosine_interpolation(n, n1, i$float/length) => s.next;
      } else {
        linear_interpolation(n, n1, i$float/length) => s.next;
      }
      i++;
    } else {
      0 => i;
      n1 => n;
      Std.rand2f(-1,1) => n1;
    }
  }
}

fun float cosine_interpolation(float a, float b, float x) {
  (1 - Math.cos(x * 3.1415927)) * .5 => float f;
  return a*(1-f) + b*f;
}

fun float linear_interpolation(float a, float b, float x) {
  return a*(1-x) + b*x;
}

fun void switch_interpolation() {
  if (interpolation == 0) {
    1 => interpolation;
    <<<"linear interpolation">>>;
  } else {
    0 => interpolation;
    <<<"cosine interpolation">>>;
  }
}


spork ~ sound();

 
while(true) {
  hi => now;
  while( hi.recv( msg ) ) {
    if( msg.isMouseMotion() ) {
      if( msg.deltaX ) {
        // move the mouse fast from left to right to modify segment length
        length + Math.sgn(msg.deltaX/3)$int => length; 
        if (length < 5) 5 => length;
        if (length > 100) 100 => length;
        <<<length, msg.deltaX>>>;
      }
    } else if( msg.isButtonDown() ) {
      // left button resets segment size
      // right button switch between linear & cosine interpolation
      if (msg.which == 0) 50 => length;
      if (msg.which == 1) switch_interpolation();
    }
  }
}