void setup() {
  size(200,200);
  background(255);
  person(50, 150, 30);
  person(100, 180, 20);
  person(150, 150, 30);
}

/*
  Draw a person centered above (x,y) having width w.
  The rest of the size is proportional to the width.
*/
void person(int x, int y, int w) {
  line(x-w/2, y, x, y-w);          // left leg
  line(x+w/2, y, x, y-w);          // right leg
  line(x, y-w, x, y-2*w);          // trunk
  line(x, y-1.5*w, x-w/2, y-2*w);  // left arm
  line(x, y-1.5*w, x+w/2, y-2*w);  // right arm
  ellipse(x, y-2.5*w, w, w);       // head
}