var x, y;

​

function preload() {

  img = loadImage('tree.jpg');

}

​

function setup() {

  createCanvas(400, 400);

  background(0);

}

​

function draw() {

  background(0);

  x = mouseX;

  y = mouseY;

  image(img, 0, 0);

  var c = get(x, y);

  fill(c);

  ellipse(x, y, 100, 100);

}

​

​

​

​

​

​