code: public SVGPath cubicTo(double c1x, double c1y, double c2x, double c2y, double x, double y) {
      return append(PATH_CUBIC_TO).append(c1x).append(c1y).append(c2x).append(c2y).append(x).append(y);
    }
docs: Cubic Bezier line to the given coordinates.
  
  @param c1x first control point x
  @param c1y first control point y
  @param c2x second control point x
  @param c2y second control point y
  @param x new coordinates
  @param y new coordinates
  @return path object, for compact syntax.