Tracking mouse coordinates

function setup() {

  createCanvas(400, 400);

  background(220);

}

​

function draw() {

  // creates the grey rectangle in the upper left corner

  fill('grey');

  stroke('grey');

  rect(0, 0, 100, 20);

​

  // sets the color of the text

  fill('black')

  stroke('black');

  strokeWeight(1);

​

  // writes the text of the current coordinates in the corner

  text("x: " + mouseX + " y: " + mouseY, 10, 15);

}