diff options
Diffstat (limited to 'addons/web/static/lib/pdfjs/src/display/font_loader.js')
| -rw-r--r-- | addons/web/static/lib/pdfjs/src/display/font_loader.js | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/addons/web/static/lib/pdfjs/src/display/font_loader.js b/addons/web/static/lib/pdfjs/src/display/font_loader.js new file mode 100644 index 00000000000..76b4f2486f7 --- /dev/null +++ b/addons/web/static/lib/pdfjs/src/display/font_loader.js @@ -0,0 +1,376 @@ +/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */ +/* Copyright 2012 Mozilla Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +/* globals PDFJS, shadow, isWorker, assert, warn, bytesToString, string32, + globalScope, FontFace, Promise */ + +'use strict'; + +PDFJS.disableFontFace = false; + +var FontLoader = { + insertRule: function fontLoaderInsertRule(rule) { + var styleElement = document.getElementById('PDFJS_FONT_STYLE_TAG'); + if (!styleElement) { + styleElement = document.createElement('style'); + styleElement.id = 'PDFJS_FONT_STYLE_TAG'; + document.documentElement.getElementsByTagName('head')[0].appendChild( + styleElement); + } + + var styleSheet = styleElement.sheet; + styleSheet.insertRule(rule, styleSheet.cssRules.length); + }, + + clear: function fontLoaderClear() { + var styleElement = document.getElementById('PDFJS_FONT_STYLE_TAG'); + if (styleElement) { + styleElement.parentNode.removeChild(styleElement); + } +//#if !(MOZCENTRAL) + this.nativeFontFaces.forEach(function(nativeFontFace) { + document.fonts.delete(nativeFontFace); + }); + this.nativeFontFaces.length = 0; +//#endif + }, +//#if !(MOZCENTRAL) + get loadTestFont() { + // This is a CFF font with 1 glyph for '.' that fills its entire width and + // height. + return shadow(this, 'loadTestFont', atob( + 'T1RUTwALAIAAAwAwQ0ZGIDHtZg4AAAOYAAAAgUZGVE1lkzZwAAAEHAAAABxHREVGABQAFQ' + + 'AABDgAAAAeT1MvMlYNYwkAAAEgAAAAYGNtYXABDQLUAAACNAAAAUJoZWFk/xVFDQAAALwA' + + 'AAA2aGhlYQdkA+oAAAD0AAAAJGhtdHgD6AAAAAAEWAAAAAZtYXhwAAJQAAAAARgAAAAGbm' + + 'FtZVjmdH4AAAGAAAAAsXBvc3T/hgAzAAADeAAAACAAAQAAAAEAALZRFsRfDzz1AAsD6AAA' + + 'AADOBOTLAAAAAM4KHDwAAAAAA+gDIQAAAAgAAgAAAAAAAAABAAADIQAAAFoD6AAAAAAD6A' + + 'ABAAAAAAAAAAAAAAAAAAAAAQAAUAAAAgAAAAQD6AH0AAUAAAKKArwAAACMAooCvAAAAeAA' + + 'MQECAAACAAYJAAAAAAAAAAAAAQAAAAAAAAAAAAAAAFBmRWQAwAAuAC4DIP84AFoDIQAAAA' + + 'AAAQAAAAAAAAAAACAAIAABAAAADgCuAAEAAAAAAAAAAQAAAAEAAAAAAAEAAQAAAAEAAAAA' + + 'AAIAAQAAAAEAAAAAAAMAAQAAAAEAAAAAAAQAAQAAAAEAAAAAAAUAAQAAAAEAAAAAAAYAAQ' + + 'AAAAMAAQQJAAAAAgABAAMAAQQJAAEAAgABAAMAAQQJAAIAAgABAAMAAQQJAAMAAgABAAMA' + + 'AQQJAAQAAgABAAMAAQQJAAUAAgABAAMAAQQJAAYAAgABWABYAAAAAAAAAwAAAAMAAAAcAA' + + 'EAAAAAADwAAwABAAAAHAAEACAAAAAEAAQAAQAAAC7//wAAAC7////TAAEAAAAAAAABBgAA' + + 'AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAEAAAAAAA' + + 'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA' + + 'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA' + + 'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA' + + 'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAMAAA' + + 'AAAAD/gwAyAAAAAQAAAAAAAAAAAAAAAAAAAAABAAQEAAEBAQJYAAEBASH4DwD4GwHEAvgc' + + 'A/gXBIwMAYuL+nz5tQXkD5j3CBLnEQACAQEBIVhYWFhYWFhYWFhYWFhYWFhYWFhYWFhYWF' + + 'hYWFhYWFhYAAABAQAADwACAQEEE/t3Dov6fAH6fAT+fPp8+nwHDosMCvm1Cvm1DAz6fBQA' + + 'AAAAAAABAAAAAMmJbzEAAAAAzgTjFQAAAADOBOQpAAEAAAAAAAAADAAUAAQAAAABAAAAAg' + + 'ABAAAAAAAAAAAD6AAAAAAAAA==' + )); + }, + + loadTestFontId: 0, + + loadingContext: { + requests: [], + nextRequestId: 0 + }, + + isSyncFontLoadingSupported: (function detectSyncFontLoadingSupport() { + if (isWorker) { + return false; + } + + // User agent string sniffing is bad, but there is no reliable way to tell + // if font is fully loaded and ready to be used with canvas. + var userAgent = window.navigator.userAgent; + var m = /Mozilla\/5.0.*?rv:(\d+).*? Gecko/.exec(userAgent); + if (m && m[1] >= 14) { + return true; + } + // TODO other browsers + if (userAgent === 'node') { + return true; + } + return false; + })(), + + nativeFontFaces: [], + + isFontLoadingAPISupported: (!isWorker && typeof document !== 'undefined' && + !!document.fonts), + + addNativeFontFace: function fontLoader_addNativeFontFace(nativeFontFace) { + this.nativeFontFaces.push(nativeFontFace); + document.fonts.add(nativeFontFace); + }, + + bind: function fontLoaderBind(fonts, callback) { + assert(!isWorker, 'bind() shall be called from main thread'); + + var rules = []; + var fontsToLoad = []; + var fontLoadPromises = []; + for (var i = 0, ii = fonts.length; i < ii; i++) { + var font = fonts[i]; + + // Add the font to the DOM only once or skip if the font + // is already loaded. + if (font.attached || font.loading === false) { + continue; + } + font.attached = true; + + if (this.isFontLoadingAPISupported) { + var nativeFontFace = font.createNativeFontFace(); + if (nativeFontFace) { + fontLoadPromises.push(nativeFontFace.loaded); + } + } else { + var rule = font.bindDOM(); + if (rule) { + rules.push(rule); + fontsToLoad.push(font); + } + } + } + + var request = FontLoader.queueLoadingCallback(callback); + if (this.isFontLoadingAPISupported) { + Promise.all(fontsToLoad).then(function() { + request.complete(); + }); + } else if (rules.length > 0 && !this.isSyncFontLoadingSupported) { + FontLoader.prepareFontLoadEvent(rules, fontsToLoad, request); + } else { + request.complete(); + } + }, + + queueLoadingCallback: function FontLoader_queueLoadingCallback(callback) { + function LoadLoader_completeRequest() { + assert(!request.end, 'completeRequest() cannot be called twice'); + request.end = Date.now(); + + // sending all completed requests in order how they were queued + while (context.requests.length > 0 && context.requests[0].end) { + var otherRequest = context.requests.shift(); + setTimeout(otherRequest.callback, 0); + } + } + + var context = FontLoader.loadingContext; + var requestId = 'pdfjs-font-loading-' + (context.nextRequestId++); + var request = { + id: requestId, + complete: LoadLoader_completeRequest, + callback: callback, + started: Date.now() + }; + context.requests.push(request); + return request; + }, + + prepareFontLoadEvent: function fontLoaderPrepareFontLoadEvent(rules, + fonts, + request) { + /** Hack begin */ + // There's currently no event when a font has finished downloading so the + // following code is a dirty hack to 'guess' when a font is + // ready. It's assumed fonts are loaded in order, so add a known test + // font after the desired fonts and then test for the loading of that + // test font. + + function int32(data, offset) { + return (data.charCodeAt(offset) << 24) | + (data.charCodeAt(offset + 1) << 16) | + (data.charCodeAt(offset + 2) << 8) | + (data.charCodeAt(offset + 3) & 0xff); + } + + function spliceString(s, offset, remove, insert) { + var chunk1 = s.substr(0, offset); + var chunk2 = s.substr(offset + remove); + return chunk1 + insert + chunk2; + } + + var i, ii; + + var canvas = document.createElement('canvas'); + canvas.width = 1; + canvas.height = 1; + var ctx = canvas.getContext('2d'); + + var called = 0; + function isFontReady(name, callback) { + called++; + // With setTimeout clamping this gives the font ~100ms to load. + if(called > 30) { + warn('Load test font never loaded.'); + callback(); + return; + } + ctx.font = '30px ' + name; + ctx.fillText('.', 0, 20); + var imageData = ctx.getImageData(0, 0, 1, 1); + if (imageData.data[3] > 0) { + callback(); + return; + } + setTimeout(isFontReady.bind(null, name, callback)); + } + + var loadTestFontId = 'lt' + Date.now() + this.loadTestFontId++; + // Chromium seems to cache fonts based on a hash of the actual font data, + // so the font must be modified for each load test else it will appear to + // be loaded already. + // TODO: This could maybe be made faster by avoiding the btoa of the full + // font by splitting it in chunks before hand and padding the font id. + var data = this.loadTestFont; + var COMMENT_OFFSET = 976; // has to be on 4 byte boundary (for checksum) + data = spliceString(data, COMMENT_OFFSET, loadTestFontId.length, + loadTestFontId); + // CFF checksum is important for IE, adjusting it + var CFF_CHECKSUM_OFFSET = 16; + var XXXX_VALUE = 0x58585858; // the "comment" filled with 'X' + var checksum = int32(data, CFF_CHECKSUM_OFFSET); + for (i = 0, ii = loadTestFontId.length - 3; i < ii; i += 4) { + checksum = (checksum - XXXX_VALUE + int32(loadTestFontId, i)) | 0; + } + if (i < loadTestFontId.length) { // align to 4 bytes boundary + checksum = (checksum - XXXX_VALUE + + int32(loadTestFontId + 'XXX', i)) | 0; + } + data = spliceString(data, CFF_CHECKSUM_OFFSET, 4, string32(checksum)); + + var url = 'url(data:font/opentype;base64,' + btoa(data) + ');'; + var rule = '@font-face { font-family:"' + loadTestFontId + '";src:' + + url + '}'; + FontLoader.insertRule(rule); + + var names = []; + for (i = 0, ii = fonts.length; i < ii; i++) { + names.push(fonts[i].loadedName); + } + names.push(loadTestFontId); + + var div = document.createElement('div'); + div.setAttribute('style', + 'visibility: hidden;' + + 'width: 10px; height: 10px;' + + 'position: absolute; top: 0px; left: 0px;'); + for (i = 0, ii = names.length; i < ii; ++i) { + var span = document.createElement('span'); + span.textContent = 'Hi'; + span.style.fontFamily = names[i]; + div.appendChild(span); + } + document.body.appendChild(div); + + isFontReady(loadTestFontId, function() { + document.body.removeChild(div); + request.complete(); + }); + /** Hack end */ + } +//#else +//bind: function fontLoaderBind(fonts, callback) { +// assert(!isWorker, 'bind() shall be called from main thread'); +// +// for (var i = 0, ii = fonts.length; i < ii; i++) { +// var font = fonts[i]; +// if (font.attached) { +// continue; +// } +// +// font.attached = true; +// font.bindDOM() +// } +// +// setTimeout(callback); +//} +//#endif +}; + +var FontFaceObject = (function FontFaceObjectClosure() { + function FontFaceObject(name, file, properties) { + this.compiledGlyphs = {}; + if (arguments.length === 1) { + // importing translated data + var data = arguments[0]; + for (var i in data) { + this[i] = data[i]; + } + return; + } + } + FontFaceObject.prototype = { +//#if !(MOZCENTRAL) + createNativeFontFace: function FontFaceObject_createNativeFontFace() { + if (!this.data) { + return null; + } + + if (PDFJS.disableFontFace) { + this.disableFontFace = true; + return null; + } + + var nativeFontFace = new FontFace(this.loadedName, this.data, {}); + + FontLoader.addNativeFontFace(nativeFontFace); + + if (PDFJS.pdfBug && 'FontInspector' in globalScope && + globalScope['FontInspector'].enabled) { + globalScope['FontInspector'].fontAdded(this); + } + return nativeFontFace; + }, +//#endif + + bindDOM: function FontFaceObject_bindDOM() { + if (!this.data) { + return null; + } + + if (PDFJS.disableFontFace) { + this.disableFontFace = true; + return null; + } + + var data = bytesToString(new Uint8Array(this.data)); + var fontName = this.loadedName; + + // Add the font-face rule to the document + var url = ('url(data:' + this.mimetype + ';base64,' + + window.btoa(data) + ');'); + var rule = '@font-face { font-family:"' + fontName + '";src:' + url + '}'; + FontLoader.insertRule(rule); + + if (PDFJS.pdfBug && 'FontInspector' in globalScope && + globalScope['FontInspector'].enabled) { + globalScope['FontInspector'].fontAdded(this, url); + } + + return rule; + }, + + getPathGenerator: function FontLoader_getPathGenerator(objs, character) { + if (!(character in this.compiledGlyphs)) { + var js = objs.get(this.loadedName + '_path_' + character); + /*jshint -W054 */ + this.compiledGlyphs[character] = new Function('c', 'size', js); + } + return this.compiledGlyphs[character]; + } + }; + return FontFaceObject; +})(); |