'use strict'; // See documentation here: http://www.microsoft.com/typography/otspec/loca.htm var _ = require('lodash'); var ByteBuffer = require('microbuffer'); function tableSize(font, isShortFormat) { var result = (font.glyphs.length + 1) * (isShortFormat ? 2 : 4); // by glyph count + tail return result; } function createLocaTable(font) { var isShortFormat = font.ttf_glyph_size < 0x20000; var buf = new ByteBuffer(tableSize(font, isShortFormat)); var location = 0; // Array of offsets in GLYF table for each glyph _.forEach(font.glyphs, function (glyph) { if (isShortFormat) { buf.writeUint16(location); location += glyph.ttf_size / 2; // actual location must be divided to 2 in short format } else { buf.writeUint32(location); location += glyph.ttf_size; //actual location is stored as is in long format } }); // The last glyph location is stored to get last glyph length if (isShortFormat) { buf.writeUint16(location); } else { buf.writeUint32(location); } return buf; } module.exports = createLocaTable;