createCanvas(400, 400);

  noStroke();

}

​

function draw() {

  drawShapes();

}

​

function drawShapes() {

  if (mouseX < width/2) {

    fill(random(255));

    rect(random(0, width/2), random(height), random(10, 30), random(10, 30));

  }

  else {

    fill(random(255), random(255), random(255));

    circle(random(width/2, width), random(height), random(10, 30));

  }

}