let drawRect = false;

​

function setup() {

  createCanvas(400, 400);

  rectMode(CENTER);

}

​

function draw() {

  background(220);

​

  // Get the current time

  let currentTime = millis();

​

  // Check if 500 milliseconds (half a second) have passed

  if (currentTime - lastTime > 500) {

    drawRect = !drawRect; // Toggle the visibility of the rectangle

    lastTime = currentTime; // Reset the timer

  }

​

  if (drawRect) {

    rect(200, 200, 200, 200);

  }

}