code: function glyf2svg(glyf, ttf) {
  
      if (!glyf) {
          return '';
      }
  
      var pathArray = [];
  
      if (!glyf.compound) {
          if (glyf.contours && glyf.contours.length) {
              pathArray.push(contours2svg(glyf.contours));
          }
  
      }
      else {
          var glyfs = glyf.glyfs;
          glyfs.forEach(function (g) {
              var glyph = ttf.glyf[g.glyphIndex];
  
              if (!glyph || !glyph.contours || !glyph.contours.length) {
                  return;
              }
  
              var contours = lang.clone(glyph.contours); // 这里需要进行matrix变换，需要复制一份
              var transform = g.transform;
              for (var i = 0, l = contours.length; i < l; i++) {
                  pathTransform(
                      contours[i],
                      transform.a,
                      transform.b,
                      transform.c,
                      transform.d,
                      transform.e,
                      transform.f
                  );
                  pathArray.push(contour2svg(contours[i]));
              }
          });
      }
  
      return pathArray.join(' ');
  }
docs: glyf转换svg
  
  @param {Object} glyf 解析后的glyf结构
  @param {Object} ttf ttf对象
  @return {string} svg文本