The y-coordinate of the end of the line is mapped 

    to the current amplitude each frame.

    The x-coordinate of the end of the line is randomly

    generated using Perlin Noise. 

*/

​

let mic, fft, spectrum, amp, vol;

let micOn = true;

let volHist = [];

let t = 0;

​

function setup() {

  createCanvas(400, 600);

​

  mic = new p5.AudioIn(print("mic detected"),

    function() {

      print("no mic detected")

    });

  mic.start(print("mic on"),

    function() {

      print("mic off")

    });

​

  amp = new p5.Amplitude();

  amp.setInput(mic);

​

  frameRate(5);

}

​

function draw() {

  background(220);

  vol = amp.getLevel();

  volHist.push(vol);

  print(vol);

  t += 0.1;

  x = width/2;

  x += (noise(t) - 0.5) * 20;

  seedling(x, height);

}

function seedling(x, y) {

  this.x = x;

  this.y = y;

​

  for (i = 0; i < volHist.length; i++) {

    this.y -= map(volHist[i], 0, 1, 0, 20);

    stroke("green");

    fill("green");

    line(width / 2, height, this.x, this.y);

  }

}

​

​

// click the mouse to turn the mic on and off

function mouseClicked() {

  if (micOn == true) {

    micOn = false

    mic.stop();

    print("mic off");

  } else {

    micOn = true;

    mic.start();

    print("mic on");

  }

}