void draw() {
  drawClock();
}
void drawClock() {
  background(192);
  translate(width/2, height/2);
  float s = second() * TWO_PI / 60.0;
  float m = minute() * TWO_PI / 60.0;
  float h = hour() * TWO_PI / 12.0;
  rotate(s);
  strokeWeight(1);
  line(0, 0, 0, -width*0.5);
  rotate(-s+m);
  strokeWeight(2);
  line(0, 0, 0, -width*0.4);
  rotate(-m+h);
  strokeWeight(4);
  line(0, 0, 0, -width*0.2);
}