code: public SVGPath smoothCubicTo(double[] c2xy, double[] xy) {
      return append(PATH_SMOOTH_CUBIC_TO).append(c2xy[0]).append(c2xy[1]).append(xy[0]).append(xy[1]);
    }
docs: Smooth Cubic Bezier line to the given coordinates.
  
  @param c2xy second control point
  @param xy new coordinates
  @return path object, for compact syntax.