let rectY = 150;

let rectW = 100;

let rectH = 100;

​

function setup() {

  createCanvas(400, 400);

}

​

function draw() {

  background(50);

​

  let result = checkMousePosition(rectX, rectY, rectW, rectH);

  if (result == true) {

    fill(255, 255, 0);

  } else {

    noFill();

  }

  stroke(255);

  rect(rectX, rectY, rectW, rectH);

}

​

function checkMousePosition(x, y, w, h) {

  let value;

  if (mouseX >= x && mouseX <= x + w &&

    mouseY >= y && mouseY <= y + h) {

    value = true;

  } else {

    value = false;

  }

  return value;

}