public boolean equals(Object obj) {
            if (obj == this) {
                return true;
            }
            if (!(obj instanceof ControlPoint)) {
                return false;
            }
            ControlPoint that = (ControlPoint) obj;
            if (this.x != that.x) {
                return false;
            }
            /*&& y == ((ControlPoint) obj).y*/;
            return true;