function getSubsetGlyfs(ttf, subset) {

    var glyphs = [];

    var indexList = ttf.findGlyf({
        unicode: subset || []
    });

    if (indexList.length) {
        glyphs = ttf.getGlyf(indexList);
    }

    glyphs.unshift(ttf.get().glyf[0]);

    return glyphs;
}
getSubsetGlyfs

@param  {ttfObject} ttf ttfobj
@param  {Array} subset subset unicode
@return {Array}     glyfs array