static Rect scaleRect(Rect r, double factorX, double factorY) {
  ret new Rect(iround(r.x*factorX), iround(r.y*factorY), iround(r.w*factorX), iround(r.h*factorY));
}

static Rect scaleRect(Rect r, double factor) {
  ret scaleRect(r, factor, factor);
}

static Rect scaleRect(double factor, Rect r) {
  ret scaleRect(r, factor);
}