Sound

var osc, envelope, fft;

​

var scaleArray = [68, 76, 82, 54, 48, 77, 67,58];

var note = 0;

​

function setup() {

  createCanvas(710, 200);

  osc = new p5.SinOsc();

​

  // Instantiate the envelope

  envelope = new p5.Env();

​

  // set attackTime, decayTime, sustainRatio, releaseTime

  envelope.setADSR(0.001, 0.5, 0.1, 0.5);

​

  // set attackLevel, releaseLevel

  envelope.setRange(10, 0);

​

  osc.start();

​

  fft = new p5.FFT();

  noStroke();

}

​

function draw() {

  background(20);

​

  if (frameCount % 8 == 0 || frameCount == 1) {

    var midiValue = scaleArray[note];

    var freqValue = midiToFreq(midiValue);

    osc.freq(freqValue);

​

    envelope.play(osc, 0, 0.1);

    note = (note + 1) % scaleArray.length;

  }

​

  // plot FFT.analyze() frequency analysis on the canvas

  var spectrum = fft.analyze();

  for (var i = 0; i < spectrum.length/20; i++) {

    fill(spectrum[i], spectrum[i]/100, 200);

    var x = map(i, 0, spectrum.length/100, 0, width);

    var h = map(spectrum[i], 0, 200,0, height);

    ellipse(x, height, spectrum.length/20, -h);

  }

}x