sclass OnePathWithOrigin > OnePath {
  settable Pt origin = pt(0, 0);
  
  *() {}
  *(S path) { super(path); }
  *(Pt *origin, S path) { super(path); }
  *(Iterable<Pt> points, bool close) {
    l = asList(points);
    origin = first(l);
    fromPoints(l, close);
    var it = iterator(points);
    if (empty(it)) ret;
    Pt firstPoint = it.next(), p = firstPoint;
    while (it.hasNext()) {
      Pt p2 = it.next();
      steps.add(ptToDigit(ptMinus(p2, p)));
      p = p2;
    }
    
    if (close)
      steps.add(ptToDigit(ptMinus(firstPoint, p)));
  }
  
  toString {
    ret origin + " " + super.toString();
  }
}