fonteditor-core/lib/ttf/otfreader.js

fonts (ttf, woff, woff2, eot, svg, otf) parse, write, transform, glyph adjust.

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports["default"] = void 0;

var _directory = _interopRequireDefault(require("./table/directory"));

var _supportOtf = _interopRequireDefault(require("./table/support-otf"));

var _reader = _interopRequireDefault(require("./reader"));

var _error = _interopRequireDefault(require("./error"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { "default": obj }; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }

function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }

var OTFReader = /*#__PURE__*/function () {
  /**
   * OTF读取函数
   *
   * @param {Object} options 写入参数
   * @constructor
   */
  function OTFReader() {
    var options = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {};

    _classCallCheck(this, OTFReader);

    options.subset = options.subset || [];
    this.options = options;
  }
  /**
   * 初始化
   *
   * @param {ArrayBuffer} buffer buffer对象
   * @return {Object} ttf对象
   */


  _createClass(OTFReader, [{
    key: "readBuffer",
    value: function readBuffer(buffer) {
      var reader = new _reader["default"](buffer, 0, buffer.byteLength, false);
      var font = {}; // version

      font.version = reader.readString(0, 4);

      if (font.version !== 'OTTO') {
        _error["default"].raise(10301);
      } // num tables


      font.numTables = reader.readUint16();

      if (font.numTables <= 0 || font.numTables > 100) {
        _error["default"].raise(10302);
      } // searchRange


      font.searchRange = reader.readUint16(); // entrySelector

      font.entrySelector = reader.readUint16(); // rangeShift

      font.rangeShift = reader.readUint16();
      font.tables = new _directory["default"](reader.offset).read(reader, font);

      if (!font.tables.head || !font.tables.cmap || !font.tables.CFF) {
        _error["default"].raise(10302);
      }

      font.readOptions = this.options; // 读取支持的表数据

      Object.keys(_supportOtf["default"]).forEach(function (tableName) {
        if (font.tables[tableName]) {
          var offset = font.tables[tableName].offset;
          font[tableName] = new _supportOtf["default"][tableName](offset).read(reader, font);
        }
      });

      if (!font.CFF.glyf) {
        _error["default"].raise(10303);
      }

      reader.dispose();
      return font;
    }
    /**
     * 关联glyf相关的信息
     *
     * @param {Object} font font对象
     */

  }, {
    key: "resolveGlyf",
    value: function resolveGlyf(font) {
      var codes = font.cmap;
      var glyf = font.CFF.glyf;
      var subsetMap = font.readOptions.subset ? font.subsetMap : null; // 当前ttf的子集列表
      // unicode

      Object.keys(codes).forEach(function (c) {
        var i = codes[c];

        if (subsetMap && !subsetMap[i]) {
          return;
        }

        if (!glyf[i].unicode) {
          glyf[i].unicode = [];
        }

        glyf[i].unicode.push(+c);
      }); // leftSideBearing

      font.hmtx.forEach(function (item, i) {
        if (subsetMap && !subsetMap[i]) {
          return;
        }

        glyf[i].advanceWidth = glyf[i].advanceWidth || item.advanceWidth || 0;
        glyf[i].leftSideBearing = item.leftSideBearing;
      }); // 设置了subsetMap之后需要选取subset中的字形

      if (subsetMap) {
        var subGlyf = [];
        Object.keys(subsetMap).forEach(function (i) {
          subGlyf.push(glyf[+i]);
        });
        glyf = subGlyf;
      }

      font.glyf = glyf;
    }
    /**
     * 清除非必须的表
     *
     * @param {Object} font font对象
     */

  }, {
    key: "cleanTables",
    value: function cleanTables(font) {
      delete font.readOptions;
      delete font.tables;
      delete font.hmtx;
      delete font.post.glyphNameIndex;
      delete font.post.names;
      delete font.subsetMap; // 删除无用的表

      var cff = font.CFF;
      delete cff.glyf;
      delete cff.charset;
      delete cff.encoding;
      delete cff.gsubrs;
      delete cff.gsubrsBias;
      delete cff.subrs;
      delete cff.subrsBias;
    }
    /**
     * 获取解析后的ttf文档
     *
     * @param {ArrayBuffer} buffer buffer对象
     *
     * @return {Object} ttf文档
     */

  }, {
    key: "read",
    value: function read(buffer) {
      this.font = this.readBuffer(buffer);
      this.resolveGlyf(this.font);
      this.cleanTables(this.font);
      return this.font;
    }
    /**
     * 注销
     */

  }, {
    key: "dispose",
    value: function dispose() {
      delete this.font;
      delete this.options;
    }
  }]);

  return OTFReader;
}();

exports["default"] = OTFReader;