/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- / /* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */ /** * Maximum file size of the font. */ var kMaxFontFileSize = 40000; /** * Maximum number of glyphs per font. */ var kMaxGlyphsCount = 65526; /** * Maximum time to wait for a font to be loaded by @font-face */ var kMaxWaitForFontFace = 1000; /** * Useful for debugging when you want to certains operations depending on how * many fonts are loaded. */ var fontCount = 0; /** * Hold a map of decoded fonts and of the standard fourteen Type1 fonts and * their acronyms. * TODO Add the standard fourteen Type1 fonts list by default * http://cgit.freedesktop.org/poppler/poppler/tree/poppler/GfxFont.cc#n65 */ var Fonts = { _active: null, get active() { return this._active || { encoding: [] }; }, set active(aName) { this._active = this[aName]; }, unicodeFromCode: function fonts_unicodeFromCode(aCode) { var unicode = GlyphsUnicode[this.active.encoding[aCode]]; return unicode ? "0x" + unicode : aCode; } }; /** * 'Font' is the class the outside world should use, it encapsulate all the font * decoding logics whatever type it is (assuming the font type is supported). * * For example to read a Type1 font and to attach it to the document: * var type1Font = new Font("MyFontName", binaryData, aFontEncoding, "Type1"); * type1Font.bind(); * * As an improvment the last parameter can be replaced by an automatic guess * of the font type based on the first byte of the file. * * FIXME There is now too many parameters, this should be turned into an * object containing all the required informations about the font */ var Font = function(aName, aFile, aEncoding, aCharset, aBBox, aType) { this.name = aName; // If the font has already been decoded simply return if (Fonts[aName]) { this.font = Fonts[aName].data; return; } fontCount++; var start = Date.now(); switch (aType) { case "Type1": var cff = new CFF(aName, aBBox, aFile); this.mimetype = "font/otf"; // Wrap the CFF data inside an OTF font file this.font = this.cover(cff); break; case "TrueType": return Fonts[aName] = { data: null, encoding: {}, charset: null, loading: false }; // TrueType is disabled for the moment since the sanitizer prevent it // from loading this.mimetype = "font/ttf"; var ttf = new TrueType(aFile); this.font = ttf.data; break; default: warn("Font " + aType + " is not supported"); break; } var end = Date.now(); Fonts[aName] = { data: this.font, encoding: aEncoding, charset: aCharset ? aCharset.slice() : null, loading: true } // Attach the font to the document this.bind(); }; /** * A bunch of the OpenType code is duplicate between this class and the * TrueType code, this is intentional and will merge in a future version * where all the code relative to OpenType will probably have its own * class and will take decision without the Fonts consent. * But at the moment it allows to develop around the TrueType rewriting * on the fly without messing up with the 'regular' Type1 to OTF conversion. */ Font.prototype = { name: null, font: null, mimetype: null, bind: function font_bind() { var data = this.font; // Compute the binary data to base 64 var str = []; var count = data.length; for (var i = 0; i < count; i++) str.push(data.getChar ? data.getChar() : String.fromCharCode(data[i])); var dataBase64 = window.btoa(str.join("")); var fontName = this.name; /** Hack begin */ // Actually there is not event when a font has finished downloading so // the following tons of code are a dirty hack to 'guess' when a font is // ready var debug = false; if (debug) { var name = document.createElement("font"); name.setAttribute("style", "position: absolute; left: 20px; top: " + (100 * fontCount + 60) + "px"); name.innerHTML = fontName; document.body.appendChild(name); } var canvas = document.createElement("canvas"); var style = "border: 1px solid black; position:absolute; top: " + (debug ? (100 * fontCount) : "-200") + "px; left: 2px; width: 340px; height: 100px"; canvas.setAttribute("style", style); canvas.setAttribute("width", 340); canvas.setAttribute("heigth", 100); document.body.appendChild(canvas); // Retrieve font charset var charset = Fonts[fontName].charset || []; // if the charset is too small make it repeat a few times var count = 30; while (count-- && charset.length <= 30) charset = charset.concat(charset.slice()); // Get the font size canvas think it will be for 'spaces' var ctx = canvas.getContext("2d"); var testString = " "; // When debugging use the characters provided by the charsets to visually // see what's happening if (debug) { for (var i = 0; i < charset.length; i++) { var unicode = new Number("0x" + GlyphsUnicode[charset[i]]); if (!unicode) error("Unicode for " + charset[i] + " is has not been found in the glyphs list"); testString += String.fromCharCode(unicode); } } ctx.font = "bold italic 20px " + fontName + ", Symbol, Arial"; var textWidth = ctx.mozMeasureText(testString); if (debug) ctx.fillText(testString, 20, 20); var start = Date.now(); var interval = window.setInterval(function canvasInterval(self) { ctx.font = "bold italic 20px " + fontName + ", Symbol, Arial"; // For some reasons the font has not loaded, so mark it loaded for the // page to proceed but cry if ((Date.now() - start) >= kMaxWaitForFontFace) { window.clearInterval(interval); Fonts[fontName].loading = false; warn("Is " + fontName + " for charset: " + charset + " loaded?"); } else if (textWidth != ctx.mozMeasureText(testString)) { window.clearInterval(interval); Fonts[fontName].loading = false; } if (debug) ctx.fillText(testString, 20, 50); }, 20, this); /** Hack end */ // Add the @font-face rule to the document var url = "url(data:" + this.mimetype + ";base64," + dataBase64 + ");"; var rule = "@font-face { font-family:'" + fontName + "';src:" + url + "}"; var styleSheet = document.styleSheets[0]; styleSheet.insertRule(rule, styleSheet.length); }, _createOpenTypeHeader: function font_createOpenTypeHeader(aFile, aOffsets, aNumTables) { // sfnt version (4 bytes) var version = [0x4F, 0x54, 0x54, 0X4F]; // numTables (2 bytes) var numTables = aNumTables; // searchRange (2 bytes) var tablesMaxPower2 = FontsUtils.getMaxPower2(numTables); var searchRange = tablesMaxPower2 * 16; // entrySelector (2 bytes) var entrySelector = Math.log(tablesMaxPower2) / Math.log(2); // rangeShift (2 bytes) var rangeShift = numTables * 16 - searchRange; var header = [].concat(version, FontsUtils.integerToBytes(numTables, 2), FontsUtils.integerToBytes(searchRange, 2), FontsUtils.integerToBytes(entrySelector, 2), FontsUtils.integerToBytes(rangeShift, 2)); aFile.set(header, aOffsets.currentOffset); aOffsets.currentOffset += header.length; aOffsets.virtualOffset += header.length; }, _createTableEntry: function font_createTableEntry(aFile, aOffsets, aTag, aData) { // tag var tag = [ aTag.charCodeAt(0), aTag.charCodeAt(1), aTag.charCodeAt(2), aTag.charCodeAt(3) ]; // offset var offset = aOffsets.virtualOffset; // Per spec tables must be 4-bytes align so add some 0x00 if needed while (aData.length & 3) aData.push(0x00); // length var length = aData.length; // checksum var checksum = FontsUtils.bytesToInteger(tag) + offset + length; var tableEntry = [].concat(tag, FontsUtils.integerToBytes(checksum, 4), FontsUtils.integerToBytes(offset, 4), FontsUtils.integerToBytes(length, 4)); aFile.set(tableEntry, aOffsets.currentOffset); aOffsets.currentOffset += tableEntry.length; aOffsets.virtualOffset += aData.length; }, _createCMAPTable: function font_createCMAPTable(aGlyphs) { var characters = new Uint16Array(kMaxGlyphsCount); for (var i = 0; i < aGlyphs.length; i++) characters[aGlyphs[i].unicode] = i + 1; // Separate the glyphs into continuous range of codes, aka segment. var ranges = []; var range = []; var count = characters.length; for (var i = 0; i < count; i++) { if (characters[i]) { range.push(i); } else if (range.length) { ranges.push(range.slice()); range = []; } } // The size in bytes of the header is equal to the size of the // different fields * length of a short + (size of the 4 parallels arrays // describing segments * length of a short). var headerSize = (12 * 2 + (ranges.length * 4 * 2)); var segCount = ranges.length + 1; var segCount2 = segCount * 2; var searchRange = FontsUtils.getMaxPower2(segCount) * 2; var searchEntry = Math.log(segCount) / Math.log(2); var rangeShift = 2 * segCount - searchRange; var cmap = [].concat( [ 0x00, 0x00, // version 0x00, 0x01, // numTables 0x00, 0x03, // platformID 0x00, 0x01, // encodingID 0x00, 0x00, 0x00, 0x0C, // start of the table record 0x00, 0x04 // format ], FontsUtils.integerToBytes(headerSize, 2), // length [0x00, 0x00], // language FontsUtils.integerToBytes(segCount2, 2), FontsUtils.integerToBytes(searchRange, 2), FontsUtils.integerToBytes(searchEntry, 2), FontsUtils.integerToBytes(rangeShift, 2) ); // Fill up the 4 parallel arrays describing the segments. var startCount = []; var endCount = []; var idDeltas = []; var idRangeOffsets = []; var glyphsIdsArray = []; var bias = 0; for (var i = 0; i < segCount - 1; i++) { var range = ranges[i]; var start = FontsUtils.integerToBytes(range[0], 2); var end = FontsUtils.integerToBytes(range[range.length - 1], 2); var delta = FontsUtils.integerToBytes(((range[0] - 1) - bias) % 65536, 2); bias += range.length; // deltas are signed shorts delta[0] ^= 0xFF; delta[1] ^= 0xFF; delta[1] += 1; startCount.push(start[0], start[1]); endCount.push(end[0], end[1]); idDeltas.push(delta[0], delta[1]); idRangeOffsets.push(0x00, 0x00); for (var j = 0; j < range.length; j++) glyphsIdsArray.push(range[j]); } startCount.push(0xFF, 0xFF); endCount.push(0xFF, 0xFF); idDeltas.push(0x00, 0x01); idRangeOffsets.push(0x00, 0x00); return cmap.concat(endCount, [0x00, 0x00], startCount, idDeltas, idRangeOffsets, glyphsIdsArray); }, cover: function font_cover(aFont) { var otf = new Uint8Array(kMaxFontFileSize); // Required Tables var CFF = aFont.data, // PostScript Font Program OS2 = [], // OS/2 and Windows Specific metrics cmap = [], // Character to glyphs mapping head = [], // Font eader hhea = [], // Horizontal header hmtx = [], // Horizontal metrics maxp = [], // Maximum profile name = [], // Naming tables post = []; // PostScript informations var tables = [CFF, OS2, cmap, head, hhea, hmtx, maxp, name, post]; // The offsets object holds at the same time a representation of where // to write the table entry information about a table and another offset // representing the offset where to draw the actual data of a particular // table var offsets = { currentOffset: 0, virtualOffset: tables.length * (4 * 4) }; // For files with only one font the offset table is the first thing of the // file this._createOpenTypeHeader(otf, offsets, tables.length); // XXX It is probable that in a future we want to get rid of this glue // between the CFF and the OTF format in order to be able to embed TrueType // data. this._createTableEntry(otf, offsets, "CFF ", CFF); /** OS/2 */ OS2 = [ 0x00, 0x03, // version 0x02, 0x24, // xAvgCharWidth 0x01, 0xF4, // usWeightClass 0x00, 0x05, // usWidthClass 0x00, 0x00, // fstype 0x02, 0x8A, // ySubscriptXSize 0x02, 0xBB, // ySubscriptYSize 0x00, 0x00, // ySubscriptXOffset 0x00, 0x8C, // ySubscriptYOffset 0x02, 0x8A, // ySuperScriptXSize 0x02, 0xBB, // ySuperScriptYSize 0x00, 0x00, // ySuperScriptXOffset 0x01, 0xDF, // ySuperScriptYOffset 0x00, 0x31, // yStrikeOutSize 0x01, 0x02, // yStrikeOutPosition 0x00, 0x00, // sFamilyClass 0x02, 0x00, 0x06, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Panose 0xFF, 0xFF, 0xFF, 0xFF, // ulUnicodeRange1 (Bits 0-31) 0xFF, 0xFF, 0xFF, 0xFF, // ulUnicodeRange1 (Bits 32-63) 0xFF, 0xFF, 0xFF, 0xFF, // ulUnicodeRange1 (Bits 64-95) 0xFF, 0xFF, 0xFF, 0xFF, // ulUnicodeRange1 (Bits 96-127) 0x2A, 0x32, 0x31, 0x2A, // achVendID 0x00, 0x20, // fsSelection 0x00, 0x2D, // usFirstCharIndex 0x00, 0x7A, // usLastCharIndex 0x00, 0x03, // sTypoAscender 0x00, 0x20, // sTypeDescender 0x00, 0x38, // sTypoLineGap 0x00, 0x5A, // usWinAscent 0x02, 0xB4, // usWinDescent 0x00, 0xCE, 0x00, 0x00, // ulCodePageRange1 (Bits 0-31) 0x00, 0x01, 0x00, 0x00, // ulCodePageRange2 (Bits 32-63) 0x00, 0x00, // sxHeight 0x00, 0x00, // sCapHeight 0x00, 0x01, // usDefaultChar 0x00, 0xCD, // usBreakChar 0x00, 0x02 // usMaxContext ]; this._createTableEntry(otf, offsets, "OS/2", OS2); //XXX Getting charstrings here seems wrong since this is another CFF glue var charstrings = aFont.getOrderedCharStrings(aFont.glyphs); /** CMAP */ cmap = this._createCMAPTable(charstrings); this._createTableEntry(otf, offsets, "cmap", cmap); /** HEAD */ head = [ 0x00, 0x01, 0x00, 0x00, // Version number 0x00, 0x00, 0x50, 0x00, // fontRevision 0x00, 0x00, 0x00, 0x00, // checksumAdjustement 0x5F, 0x0F, 0x3C, 0xF5, // magicNumber 0x00, 0x00, // Flags 0x03, 0xE8, // unitsPerEM (defaulting to 1000) 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // creation date 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // modifification date 0x00, 0x00, // xMin 0x00, 0x00, // yMin 0x00, 0x00, // xMax 0x00, 0x00, // yMax 0x00, 0x00, // macStyle 0x00, 0x00, // lowestRecPPEM 0x00, 0x00, // fontDirectionHint 0x00, 0x00, // indexToLocFormat 0x00, 0x00 // glyphDataFormat ]; this._createTableEntry(otf, offsets, "head", head); /** HHEA */ hhea = [].concat( [ 0x00, 0x01, 0x00, 0x00, // Version number 0x00, 0x00, // Typographic Ascent 0x00, 0x00, // Typographic Descent 0x00, 0x00, // Line Gap 0xFF, 0xFF, // advanceWidthMax 0x00, 0x00, // minLeftSidebearing 0x00, 0x00, // minRightSidebearing 0x00, 0x00, // xMaxExtent 0x00, 0x00, // caretSlopeRise 0x00, 0x00, // caretSlopeRun 0x00, 0x00, // caretOffset 0x00, 0x00, // -reserved- 0x00, 0x00, // -reserved- 0x00, 0x00, // -reserved- 0x00, 0x00, // -reserved- 0x00, 0x00 // metricDataFormat ], FontsUtils.integerToBytes(charstrings.length, 2) // numberOfHMetrics ); this._createTableEntry(otf, offsets, "hhea", hhea); /** HMTX */ hmtx = [0x01, 0xF4, 0x00, 0x00]; for (var i = 0; i < charstrings.length; i++) { var charstring = charstrings[i].charstring; var width = FontsUtils.integerToBytes(charstring[1], 2); var lsb = FontsUtils.integerToBytes(charstring[0], 2); hmtx = hmtx.concat(width, lsb); } this._createTableEntry(otf, offsets, "hmtx", hmtx); /** MAXP */ maxp = [].concat( [ 0x00, 0x00, 0x50, 0x00, // Version number ], FontsUtils.integerToBytes(charstrings.length + 1, 2) // Num of glyphs (+1 to pass the sanitizer...) ); this._createTableEntry(otf, offsets, "maxp", maxp); /** NAME */ name = [ 0x00, 0x00, // format 0x00, 0x00, // Number of names Record 0x00, 0x00 // Storage ]; this._createTableEntry(otf, offsets, "name", name); /** POST */ // FIXME Get those informations from the FontInfo structure post = [ 0x00, 0x03, 0x00, 0x00, // Version number 0x00, 0x00, 0x01, 0x00, // italicAngle 0x00, 0x00, // underlinePosition 0x00, 0x00, // underlineThickness 0x00, 0x00, 0x00, 0x00, // isFixedPitch 0x00, 0x00, 0x00, 0x00, // minMemType42 0x00, 0x00, 0x00, 0x00, // maxMemType42 0x00, 0x00, 0x00, 0x00, // minMemType1 0x00, 0x00, 0x00, 0x00 // maxMemType1 ]; this._createTableEntry(otf, offsets, "post", post); // Once all the table entries header are written, dump the data! var tables = [CFF, OS2, cmap, head, hhea, hmtx, maxp, name, post]; for (var i = 0; i < tables.length; i++) { var table = tables[i]; otf.set(table, offsets.currentOffset); offsets.currentOffset += table.length; } var fontData = []; for (var i = 0; i < offsets.currentOffset; i++) fontData.push(otf[i]); return fontData; } }; /** * FontsUtils is a static class dedicated to hold codes that are not related * to fonts in particular and needs to be share between them. */ var FontsUtils = { _bytesArray: new Uint8Array(4), integerToBytes: function fu_integerToBytes(aValue, aBytesCount) { var bytes = this._bytesArray; if (aBytesCount == 1) { bytes.set([aValue]); return bytes[0]; } else if (aBytesCount == 2) { bytes.set([aValue >> 8, aValue]); return [bytes[0], bytes[1]]; } else if (aBytesCount == 4) { bytes.set([aValue >> 24, aValue >> 16, aValue >> 8, aValue]); return [bytes[0], bytes[1], bytes[2], bytes[3]]; } }, bytesToInteger: function fu_bytesToInteger(aBytesArray) { var value = 0; for (var i = 0; i < aBytesArray.length; i++) value = (value << 8) + aBytesArray[i]; return value; }, getMaxPower2: function fu_getMaxPower2(aNumber) { var maxPower = 0; var value = aNumber; while (value >= 2) { value /= 2; maxPower++; } value = 2; for (var i = 1; i < maxPower; i++) value *= 2; return value; } }; /** * The TrueType class verify that the ttf embedded inside the PDF is correct in * the point of view of the OTS sanitizer and rewrite it on the fly otherwise. * * At the moment the rewiting only support rewriting missing 'OS/2' table. * This class is unused at the moment since the 'cmap' table of the test * document is not missing but use and old version of the 'cmap' table that * is deprecated and not supported by the sanitizer... * */ var TrueType = function(aFile) { var header = this._readOpenTypeHeader(aFile); var numTables = header.numTables; // Check that required tables are present var requiredTables = [ "OS/2", "cmap", "head", "hhea", "hmtx", "maxp", "name", "post" ]; var tables = []; for (var i = 0; i < numTables; i++) { var table = this._readTableEntry(aFile); var index = requiredTables.indexOf(table.tag); if (index != -1) requiredTables.splice(index, 1); tables.push(table); } // Tables needs to be written by ascendant alphabetic order tables.sort(function(a, b) { return a.tag > b.tag; }); // If any tables are still in the array this means some required tables are // missing, which means that we need to rebuild the font in order to pass // the sanitizer. if (requiredTables.length && requiredTables[0] == "OS/2") { OS2 = [ 0x00, 0x03, // version 0x02, 0x24, // xAvgCharWidth 0x01, 0xF4, // usWeightClass 0x00, 0x05, // usWidthClass 0x00, 0x00, // fstype 0x02, 0x8A, // ySubscriptXSize 0x02, 0xBB, // ySubscriptYSize 0x00, 0x00, // ySubscriptXOffset 0x00, 0x8C, // ySubscriptYOffset 0x02, 0x8A, // ySuperScriptXSize 0x02, 0xBB, // ySuperScriptYSize 0x00, 0x00, // ySuperScriptXOffset 0x01, 0xDF, // ySuperScriptYOffset 0x00, 0x31, // yStrikeOutSize 0x01, 0x02, // yStrikeOutPosition 0x00, 0x00, // sFamilyClass 0x02, 0x00, 0x06, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Panose 0xFF, 0xFF, 0xFF, 0xFF, // ulUnicodeRange1 (Bits 0-31) 0xFF, 0xFF, 0xFF, 0xFF, // ulUnicodeRange1 (Bits 32-63) 0xFF, 0xFF, 0xFF, 0xFF, // ulUnicodeRange1 (Bits 64-95) 0xFF, 0xFF, 0xFF, 0xFF, // ulUnicodeRange1 (Bits 96-127) 0x2A, 0x32, 0x31, 0x2A, // achVendID 0x00, 0x20, // fsSelection 0x00, 0x2D, // usFirstCharIndex 0x00, 0x7A, // usLastCharIndex 0x00, 0x03, // sTypoAscender 0x00, 0x20, // sTypeDescender 0x00, 0x38, // sTypoLineGap 0x00, 0x5A, // usWinAscent 0x02, 0xB4, // usWinDescent 0x00, 0xCE, 0x00, 0x00, // ulCodePageRange1 (Bits 0-31) 0x00, 0x01, 0x00, 0x00, // ulCodePageRange2 (Bits 32-63) 0x00, 0x00, // sxHeight 0x00, 0x00, // sCapHeight 0x00, 0x01, // usDefaultChar 0x00, 0xCD, // usBreakChar 0x00, 0x02 // usMaxContext ]; // Create a new file to hold the new version of our truetype with a new // header and new offsets var stream = aFile.stream || aFile; var ttf = new Uint8Array(stream.length + 16 + OS2.length); // The new numbers of tables will be the last one plus the num of missing // tables var numTables = header.numTables + 1; // The offsets object holds at the same time a representation of where // to write the table entry information about a table and another offset // representing the offset where to draw the actual data of a particular // table var offsets = { currentOffset: 0, virtualOffset: numTables * (4 * 4) }; // Write the sfnt header with one more table this._createOpenTypeHeader(ttf, offsets, numTables); // Insert the missing table tables.unshift({ tag: "OS/2", data: OS2 }); // rewrite the tables but tweak offsets for (var i = 0; i < tables.length; i++) { var table = tables[i]; var data = []; var tableData = table.data; for (var j = 0; j < tableData.length; j++) data.push(tableData[j]); this._createTableEntry(ttf, offsets, table.tag, data); } // Add the table datas for (var i = 0; i < tables.length; i++) { var table = tables[i]; var tableData = table.data; ttf.set(tableData, offsets.currentOffset); offsets.currentOffset += tableData.length; if (0) { var data = []; for (var j = 0; j < tableData.length; j++) d.push(tableData[j]); log("data for table: " + table.tag + ": " + data); } // 4-byte aligned data while (offsets.currentOffset & 3) offsets.currentOffset++; } var fontData = []; for (var i = 0; i < ttf.length; i++) fontData.push(ttf[i]); this.data = ttf; return; } else if (requiredTables.lenght) { error("Table " + requiredTables[0] + " is missing from the TruType font"); } else { this.data = aFile; } }; TrueType.prototype = { _createOpenTypeHeader: function tt_createOpenTypeHeader(aFile, aOffsets, aNumTables) { // sfnt version (4 bytes) // XXX if we want to merge this function and the one from the Font class // XXX this need to be adapted var version = [0x00, 0x01, 0x00, 0X00]; // numTables (2 bytes) var numTables = aNumTables; // searchRange (2 bytes) var tablesMaxPower2 = FontsUtils.getMaxPower2(numTables); var searchRange = tablesMaxPower2 * 16; // entrySelector (2 bytes) var entrySelector = Math.log(tablesMaxPower2) / Math.log(2); // rangeShift (2 bytes) var rangeShift = numTables * 16 - searchRange; var header = [].concat(version, FontsUtils.integerToBytes(numTables, 2), FontsUtils.integerToBytes(searchRange, 2), FontsUtils.integerToBytes(entrySelector, 2), FontsUtils.integerToBytes(rangeShift, 2)); aFile.set(header, aOffsets.currentOffset); aOffsets.currentOffset += header.length; aOffsets.virtualOffset += header.length; }, _createTableEntry: function font_createTableEntry(aFile, aOffsets, aTag, aData) { // tag var tag = [ aTag.charCodeAt(0), aTag.charCodeAt(1), aTag.charCodeAt(2), aTag.charCodeAt(3) ]; // Per spec tables must be 4-bytes align so add some 0x00 if needed while (aData.length & 3) aData.push(0x00); while (aOffsets.virtualOffset & 3) aOffsets.virtualOffset++; // offset var offset = aOffsets.virtualOffset; // length var length = aData.length; // checksum var checksum = FontsUtils.bytesToInteger(tag) + offset + length; var tableEntry = [].concat(tag, FontsUtils.integerToBytes(checksum, 4), FontsUtils.integerToBytes(offset, 4), FontsUtils.integerToBytes(length, 4)); aFile.set(tableEntry, aOffsets.currentOffset); aOffsets.currentOffset += tableEntry.length; aOffsets.virtualOffset += aData.length; }, _readOpenTypeHeader: function tt_readOpenTypeHeader(aFile) { return { version: aFile.getBytes(4), numTables: FontsUtils.bytesToInteger(aFile.getBytes(2)), searchRange: FontsUtils.bytesToInteger(aFile.getBytes(2)), entrySelector: FontsUtils.bytesToInteger(aFile.getBytes(2)), rangeShift: FontsUtils.bytesToInteger(aFile.getBytes(2)) } }, _readTableEntry: function tt_readTableEntry(aFile) { // tag var tag = aFile.getBytes(4); tag = String.fromCharCode(tag[0]) + String.fromCharCode(tag[1]) + String.fromCharCode(tag[2]) + String.fromCharCode(tag[3]); var checksum = FontsUtils.bytesToInteger(aFile.getBytes(4)); var offset = FontsUtils.bytesToInteger(aFile.getBytes(4)); var length = FontsUtils.bytesToInteger(aFile.getBytes(4)); // Read the table associated data var currentPosition = aFile.pos; aFile.pos = aFile.start + offset; var data = aFile.getBytes(length); aFile.pos = currentPosition; return { tag: tag, checksum: checksum, length: offset, offset: length, data: data } } }; /** * This dictionary holds decoded fonts data. */ var Type1Parser = function() { // Turn on this flag for additional debugging logs var debug = false; var dump = function(aData) { if (debug) log(aData); }; /* * Decrypt a Sequence of Ciphertext Bytes to Produce the Original Sequence * of Plaintext Bytes. The function took a key as a parameter which can be * for decrypting the eexec block of for decoding charStrings. */ var kEexecEncryptionKey = 55665; var kCharStringsEncryptionKey = 4330; function decrypt(aStream, aKey, aDiscardNumber, aByteArray) { var start = Date.now(); var r = aKey, c1 = 52845, c2 = 22719; var decryptedString = []; var value = ""; var count = aStream.length; for (var i = 0; i < count; i++) { value = aStream[i]; if (aByteArray) decryptedString[i] = value ^ (r >> 8); else decryptedString[i] = String.fromCharCode(value ^ (r >> 8)); r = ((value + r) * c1 + c2) & ((1 << 16) - 1); } var end = Date.now(); dump("Time to decrypt string of length " + count + " is " + (end - start)); return decryptedString.slice(aDiscardNumber); }; /* * CharStrings are encoded following the the CharString Encoding sequence * describe in Chapter 6 of the "Adobe Type1 Font Format" specification. * The value in a byte indicates a command, a number, or subsequent bytes * that are to be interpreted in a special way. * * CharString Number Encoding: * A CharString byte containing the values from 32 through 255 inclusive * indicate an integer. These values are decoded in four ranges. * * 1. A CharString byte containing a value, v, between 32 and 246 inclusive, * indicate the integer v - 139. Thus, the integer values from -107 through * 107 inclusive may be encoded in single byte. * * 2. A CharString byte containing a value, v, between 247 and 250 inclusive, * indicates an integer involving the next byte, w, according to the formula: * [(v - 247) x 256] + w + 108 * * 3. A CharString byte containing a value, v, between 251 and 254 inclusive, * indicates an integer involving the next byte, w, according to the formula: * -[(v - 251) * 256] - w - 108 * * 4. A CharString containing the value 255 indicates that the next 4 bytes * are a two complement signed integer. The first of these bytes contains the * highest order bits, the second byte contains the next higher order bits * and the fourth byte contain the lowest order bits. * * * CharString Command Encoding: * CharStrings commands are encoded in 1 or 2 bytes. * * Single byte commands are encoded in 1 byte that contains a value between * 0 and 31 inclusive. * If a command byte contains the value 12, then the value in the next byte * indicates a command. This "escape" mechanism allows many extra commands * to be encoded and this encoding technique helps to minimize the length of * the charStrings. */ var charStringDictionary = { "1": "hstem", "3": "vstem", "4": "vmoveto", "5": "rlineto", "6": "hlineto", "7": "vlineto", "8": "rrcurveto", // closepath is a Type1 command that do not take argument and is useless // in Type2 and it can simply be ignored. "9": null, // closepath "10": "callsubr", // return is normally used inside sub-routines to tells to the execution // flow that it can be back to normal. // During the translation process Type1 charstrings will be flattened and // sub-routines will be embedded directly into the charstring directly, so // this can be ignored safely. "11": "return", "12": { // dotsection is a Type1 command to specify some hinting feature for dots // that do not take a parameter and it can safely be ignored for Type2. "0": null, // dotsection // [vh]stem3 are Type1 only and Type2 supports [vh]stem with multiple // parameters, so instead of returning [vh]stem3 take a shortcut and // return [vhstem] instead. "1": "vstem", "2": "hstem", // Type1 only command with command not (yet) built-in ,throw an error "6": -1, // seac "7": -1, //sbw "12": "div", // callothersubr is a mechanism to make calls on the postscript // interpreter. // TODO When decodeCharstring encounter such a command it should // directly do: // - pop the previous charstring[] command into 'index' // - pop the previous charstring[] command and ignore it, it is // normally the number of element to push on the stack before // the command but since everything will be pushed on the stack // by the PS interpreter when it will read them that is safe to // ignore this command // - push the content of the OtherSubrs[index] inside charstring[] "16": "callothersubr", "17": "pop", // setcurrentpoint sets the current point to x, y without performing a // moveto (this is a one shot positionning command). This is used only // with the return of an OtherSubrs call. // TODO Implement the OtherSubrs charstring embedding and replace this // call by a no-op, like 2 'pop' commands for example. "33": null, //setcurrentpoint }, "13": "hsbw", "14": "endchar", "21": "rmoveto", "22": "hmoveto", "30": "vhcurveto", "31": "hvcurveto" }; function decodeCharString(aArray) { var charString = []; var value = ""; var count = aArray.length; for (var i = 0; i < count; i++) { value = parseInt(aArray[i]); if (value < 32) { var command = null; if (value == 12) { var escape = aArray[++i]; command = charStringDictionary["12"][escape]; } else { command = charStringDictionary[value]; } // Some charstring commands are meaningless in Type2 and will return // a null, let's just ignored them if (!command && i < count) { continue; } else if (!command) { break; } else if (command == -1) { log("decodeCharstring: " + charString); error("Support for Type1 command " + value + " (" + escape + ") is not implemented"); } value = command; } else if (value <= 246) { value = parseInt(value) - 139; } else if (value <= 250) { value = ((value - 247) * 256) + parseInt(aArray[++i]) + 108; } else if (value <= 254) { value = -((value - 251) * 256) - parseInt(aArray[++i]) - 108; } else { var byte = aArray[++i]; var high = (byte >> 1); value = (byte - high) << 24 | aArray[++i] << 16 | aArray[++i] << 8 | aArray[++i]; } charString.push(value); } return charString; }; /** * Returns an object containing a Subrs array and a CharStrings array * extracted from and eexec encrypted block of data */ this.extractFontInfo = function(aStream) { var eexecString = decrypt(aStream, kEexecEncryptionKey, 4, true); var subrs = [], glyphs = []; var inSubrs = inGlyphs = false; var glyph = ""; var token = ""; var index = 0; var length = 0; var count = eexecString.length; var c = ""; for (var i = 0; i < count; i++) { var c = eexecString[i]; if (inSubrs && c == 0x52) { length = parseInt(length); var data = eexecString.slice(i + 3, i + 3 + length); var encodedSubr = decrypt(data, kCharStringsEncryptionKey, 4, true); var subr = decodeCharString(encodedSubr); subrs.push(subr); i += 3 + length; } else if (inGlyphs && c == 0x52) { length = parseInt(length); var data = eexecString.slice(i + 3, i + 3 + length); var encodedCharstring = decrypt(data, kCharStringsEncryptionKey, 4, true); var subr = decodeCharString(encodedCharstring); glyphs.push({ glyph: glyph, data: subr }); i += 3 + length; } else if (inGlyphs && c == 0x2F) { token = ""; glyph = ""; while ((c = eexecString[++i]) != 0x20) glyph += String.fromCharCode(c); } else if (!inSubrs && !inGlyphs && c == 0x2F && eexecString[i+1] == 0x53) { while ((c = eexecString[++i]) != 0x20) {}; inSubrs = true; } else if (c == 0x20) { index = length; length = token; token = ""; } else if (c == 0x2F && eexecString[i+1] == 0x43 && eexecString[i+2] == 0x68) { while ((c = eexecString[++i]) != 0x20) {}; inSubrs = false; inGlyphs = true; } else { token += String.fromCharCode(c); } } return { subrs: subrs, charstrings: glyphs } } }; var CFF = function(aFontName, aFontBBox, aFontFile) { // Get the data block containing glyphs and subrs informations var length1 = aFontFile.dict.get("Length1"); var length2 = aFontFile.dict.get("Length2"); aFontFile.skip(length1); var eexecBlock = aFontFile.getBytes(length2); // Extract informations from it var start = Date.now(); var parser = new Type1Parser(); var fontInfo = parser.extractFontInfo(eexecBlock); fontInfo.name = aFontName; fontInfo.bbox = aFontBBox; // XXX This hold the glyph data as if, this should be improved this.glyphs = fontInfo.charstrings; this.data = this.convertToCFF(fontInfo); var end = Date.now(); }; CFF.prototype = { createCFFIndexHeader: function(aObjects, aIsByte) { var data = []; // First 2 bytes contains the number of objects contained into this index var count = aObjects.length; if (count ==0) return [0x00, 0x00, 0x00]; var bytes = FontsUtils.integerToBytes(count, 2); for (var i = 0; i < bytes.length; i++) data.push(bytes[i]); // Next byte contains the offset size use to reference object in the file // Actually we're using 0x04 to be sure to be able to store everything // without thinking of it while coding. data.push(0x04); // Add another offset after this one because we need a new offset var relativeOffset = 1; for (var i = 0; i < count + 1; i++) { var bytes = FontsUtils.integerToBytes(relativeOffset, 4); for (var j = 0; j < bytes.length; j++) data.push(bytes[j]); if (aObjects[i]) relativeOffset += aObjects[i].length; } for (var i =0; i < count; i++) { for (var j = 0; j < aObjects[i].length; j++) data.push(aIsByte ? aObjects[i][j] : aObjects[i].charCodeAt(j)); } return data; }, encodeNumber: function(aValue) { var x = 0; if (aValue >= -32768 && aValue <= 32767) { return [ 28, aValue >> 8, aValue ]; } else if (aValue >= (-2147483647-1) && aValue <= 2147483647) { return [ 0xFF, aValue >> 24, Value >> 16, aValue >> 8, aValue ]; } else { error("Value: " + aValue + " is not allowed"); } }, getOrderedCharStrings: function(aGlyphs) { var charstrings = []; for (var i = 0; i < aGlyphs.length; i++) { var glyph = aGlyphs[i].glyph; var unicode = GlyphsUnicode[glyph]; if (!unicode) { if (glyph != ".notdef") warn(glyph + " does not have an entry in the glyphs unicode dictionary"); } else { var b1 = parseInt("0x" + unicode[0] + unicode[1]); var b2 = parseInt("0x" + unicode[2] + unicode[3]); unicode = FontsUtils.bytesToInteger([b1, b2]); charstrings.push({ glyph: glyph, unicode: unicode, charstring: aGlyphs[i].data.slice() }); } }; charstrings.sort(function(a, b) { return a.unicode > b.unicode; }); return charstrings; }, /* * Flatten the commands by interpreting the postscript code and replacing * every 'callsubr', 'callothersubr' by the real commands. * * TODO This function also do a string to command number transformation * that can probably be avoided if the Type1 decodeCharstring code is smarter */ commandsMap: { "hstem": 1, "vstem": 3, "vmoveto": 4, "rlineto": 5, "hlineto": 6, "vlineto": 7, "rrcurveto": 8, "endchar": 14, "rmoveto": 21, "hmoveto": 22, "vhcurveto": 30, "hvcurveto": 31, }, flattenCharstring: function(aCharstring, aSubrs) { var original = aCharstring.slice(); var i = 0; while (true) { var obj = aCharstring[i]; if (obj.charAt) { switch (obj) { case "callsubr": if (aCharstring[i - 1] == 351) { log(original); log(aCharstring); error("..."); aCharstring.splice(i - 1, 2); continue; } var subr = aSubrs[aCharstring[i - 1]].slice(); if (subr.length > 1) { subr = this.flattenCharstring(subr, aSubrs); subr.pop(); aCharstring.splice(i - 1, 2, subr); } else aCharstring.splice(i - 1, 2); i -= 1; break; case "callothersubr": var index = aCharstring[i - 1]; var count = aCharstring[i - 2]; var data = aCharstring[i - 3]; // XXX The callothersubr needs to support at least the 3 defaults // otherSubrs of the spec if (index != 3) error("callothersubr for index: " + index + " (" + aCharstring + ")"); if (!data) { aCharstring.splice(i - 2, 3, "pop", 3); i -= 2; } else { // 5 to remove the arguments, the callothersubr call and the pop command aCharstring.splice(i - 3, 5, 3); i -= 3; } break; case "div": var num2 = aCharstring[i - 1]; var num1 = aCharstring[i - 2]; aCharstring.splice(i - 2, 3, num2 / num1); i -= 2; break; case "pop": aCharstring.splice(i - 2, 2); i -= 1; break; case "hsbw": var charWidthVector = aCharstring[i - 1]; var leftSidebearing = aCharstring[i - 2]; aCharstring.splice(i - 2, 3, charWidthVector, leftSidebearing, "hmoveto"); break; case "endchar": case "return": // CharString is ready to be re-encode to commands number at this point for (var j = 0; j < aCharstring.length; j++) { var command = aCharstring[j]; if (parseFloat(command) == command) { aCharstring.splice(j, 1, 28, command >> 8, command); j+= 2; } else if (command.charAt) { var command = this.commandsMap[command]; if (IsArray(command)) { aCharstring.splice(j - 1, 1, command[0], command[1]); j += 1; } else { aCharstring[j] = command; } } else { aCharstring.splice(j, 1); // command has already been translated, just add them to the // charstring directly for (var k = 0; k < command.length; k++) aCharstring.splice(j + k, 0, command[k]); j+= command.length - 1; } } return aCharstring; default: break; } } i++; } error("failing with i = " + i + " in charstring:" + aCharstring + "(" + aCharstring.length + ")"); }, convertToCFF: function(aFontInfo) { var debug = false; function dump(aMsg) { if (debug) log(aMsg); }; var charstrings = this.getOrderedCharStrings(aFontInfo.charstrings); // Starts the conversion of the Type1 charstrings to Type2 var start = Date.now(); var charstringsCount = 0; var charstringsDataLength = 0; var glyphs = []; for (var i = 0; i < charstrings.length; i++) { var charstring = charstrings[i].charstring.slice(); var glyph = charstrings[i].glyph; var flattened = this.flattenCharstring(charstring, aFontInfo.subrs); glyphs.push(flattened); charstringsCount++; charstringsDataLength += flattened.length; } var end = Date.now(); dump("There is " + charstringsCount + " glyphs (size: " + charstringsDataLength + ")"); dump("Time to flatten the strings is : " + (end -start)); // Create a CFF font data var cff = new Uint8Array(kMaxFontFileSize); var currentOffset = 0; // Font header (major version, minor version, header size, offset size) var header = [0x01, 0x00, 0x04, 0x04]; currentOffset += header.length; cff.set(header); // Names Index var nameIndex = this.createCFFIndexHeader([aFontInfo.name]); cff.set(nameIndex, currentOffset); currentOffset += nameIndex.length; // Calculate strings before writing the TopDICT index in order // to calculate correct relative offsets for storing 'charset' // and 'charstrings' data var version = ""; var notice = ""; var fullName = ""; var familyName = ""; var weight = ""; var strings = [version, notice, fullName, familyName, weight]; var stringsIndex = this.createCFFIndexHeader(strings); var stringsDataLength = stringsIndex.length; // Create the global subroutines index var globalSubrsIndex = this.createCFFIndexHeader([]); // Fill the charset header (first byte is the encoding) var charset = [0x00]; for (var i = 0; i < glyphs.length; i++) { var index = CFFStrings.indexOf(charstrings[i].glyph); if (index == -1) index = CFFStrings.length + strings.indexOf(glyph); var bytes = FontsUtils.integerToBytes(index, 2); charset.push(bytes[0]); charset.push(bytes[1]); } var charstringsIndex = this.createCFFIndexHeader([[0x40, 0x0E]].concat(glyphs), true); charstringsIndex = charstringsIndex.join(" ").split(" "); // XXX why? //Top Dict Index var topDictIndex = [ 0x00, 0x01, 0x01, 0x01, 0x30, 248, 27, 0, // version 248, 28, 1, // Notice 248, 29, 2, // FullName 248, 30, 3, // FamilyName 248, 31, 4 // Weight ]; var fontBBox = aFontInfo.bbox; for (var i = 0; i < fontBBox.length; i++) topDictIndex = topDictIndex.concat(this.encodeNumber(fontBBox[i])); topDictIndex.push(5) // FontBBox; var charsetOffset = currentOffset + (topDictIndex.length + (4 + 4 + 4 + 7)) + stringsIndex.length + globalSubrsIndex.length; topDictIndex = topDictIndex.concat(this.encodeNumber(charsetOffset)); topDictIndex.push(15); // charset topDictIndex = topDictIndex.concat([28, 0, 0, 16]) // Encoding var charstringsOffset = charsetOffset + (charstringsCount * 2) + 1; topDictIndex = topDictIndex.concat(this.encodeNumber(charstringsOffset)); topDictIndex.push(17); // charstrings topDictIndex = topDictIndex.concat([28, 0, 55]) var privateOffset = charstringsOffset + charstringsIndex.length; topDictIndex = topDictIndex.concat(this.encodeNumber(privateOffset)); topDictIndex.push(18); // Private topDictIndex = topDictIndex.join(" ").split(" "); var indexes = [ topDictIndex, stringsIndex, globalSubrsIndex, charset, charstringsIndex ]; for (var i = 0; i < indexes.length; i++) { var index = indexes[i]; cff.set(index, currentOffset); currentOffset += index.length; } // Private Data var defaultWidth = this.encodeNumber(0); var privateData = [].concat( defaultWidth, [20], [139, 21], // nominalWidth [ 119, 159, 248, 97, 159, 247, 87, 159, 6, 30, 10, 3, 150, 37, 255, 12, 9, 139, 12, 10, 172, 10, 172, 150, 143, 146, 150, 146, 12, 12, 247, 32, 11, 247, 10, 161, 147, 154, 150, 143, 12, 13, 139, 12, 14, 28, 0, 55, 19 ]); privateData = privateData.join(" ").split(" "); cff.set(privateData, currentOffset); currentOffset += privateData.length; // Dump shit at the end of the file var shit = [ 0x00, 0x01, 0x01, 0x01, 0x13, 0x5D, 0x65, 0x64, 0x5E, 0x5B, 0xAF, 0x66, 0xBA, 0xBB, 0xB1, 0xB0, 0xB9, 0xBA, 0x65, 0xB2, 0x5C, 0x1F, 0x0B ]; cff.set(shit, currentOffset); currentOffset += shit.length; var fontData = []; for (var i = 0; i < currentOffset; i++) fontData.push(cff[i]); return fontData; } };