code: function mirrorPaths(paths, xScale, yScale) {
  
              var bound = computeBoundingBox.computePath.apply(null, paths);
              var x = bound.x;
              var y = bound.y;
              var w = bound.width;
              var h = bound.height;
  
              if (xScale === -1) {
                  paths.forEach(function (p) {
                      pathAdjust(p, -1, 1, -x, 0);
                      pathAdjust(p, 1, 1, x + w, 0);
                      p.reverse();
                  });
  
              }
  
              if (yScale === -1) {
                  paths.forEach(function (p) {
                      pathAdjust(p, 1, -1, 0, -y);
                      pathAdjust(p, 1, 1, 0, y + h);
                      p.reverse();
                  });
              }
  
              return paths;
          }
docs: 翻转路径
  
  @param {Array} paths 路径数组
  @param {number} xScale x翻转
  @param {number} yScale y翻转
  @return {Array} 变换后的路径