​

let synth, soundLoop;

let notePattern = [60, 62, 64, 67, 69, 72, 76];

let noteIndex = 0;

​

 function setup() {

   let cnv = createCanvas(400, 400);

   cnv.mousePressed(canvasPressed);

   colorMode(HSB);

   background(0, 0, 86);

   text('tap to start/stop', 10, 20);

​

   //the looper's callback is passed the timeFromNow

   //this value should be used as a reference point from

   //which to schedule sounds

   let intervalInSeconds = 1;

   soundLoop = new p5.SoundLoop(onSoundLoop, intervalInSeconds);

​

   synth = new p5.MonoSynth();

}

​

function canvasPressed() {

  // ensure audio is enabled

  userStartAudio();

​

  if (soundLoop.isPlaying) {

    soundLoop.stop();

  } else {

    // start the loop

    soundLoop.start();

  }

}

​

function onSoundLoop(timeFromNow) {

  noteIndex++;

    if (noteIndex>=notePattern.length){

      noteIndex=0;

    }

  let note = midiToFreq(notePattern[noteIndex]);

  synth.play(note, 0.5, timeFromNow);

  background(noteIndex * 360 / notePattern.length, 50, 100);

}