code: function getSinglePath(points, smooth, isInCircle, cfg) {
    var path = void 0;
    if (!smooth) {
      path = PathUtil.getLinePath(points, false);
      if (isInCircle) {
        path.push(['Z']);
      }
    } else {
      // 直角坐标系下绘制曲线时限制最大值、最小值
      var constraint = cfg.constraint;
      if (isInCircle && points.length) {
        points.push({ x: points[0].x, y: points[0].y });
      }
      path = PathUtil.getSplinePath(points, false, constraint);
    }
  
    return path;
  }
docs: 单条 path