执行后，代码显示在屏幕上而不是循环播放

Question

打印带有坐标在屏幕上移动的十字准线 在它下面

function setup() {
  createCanvas(600, 480);
  background('grey');
}

function draw() {
  for (var x = 0; x < width; x++) {
    ellipse(x, mouseY, 5);
  }
  for (var y = 0; y < height; y++) {
    ellipse(mouseX, y, 5);
  }
  text("X: " + mouseX, mouseX, mouseY);
  text("Y: " + mouseY, mouseX, mouseY);
}