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Refactors CMapFactory.create to make it async

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Manas 2016-02-28 21:50:29 +05:30
parent c6d2b7f9d9
commit f6d28ca323
8 changed files with 559 additions and 473 deletions
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134
src/core/fonts.js
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@ -501,7 +501,7 @@ var Font = (function FontClosure() {
this.fontMatrix = properties.fontMatrix;
this.bbox = properties.bbox;
this.toUnicode = properties.toUnicode = this.buildToUnicode(properties);
this.toUnicode = properties.toUnicode;
this.toFontChar = [];
@ -2665,138 +2665,6 @@ var Font = (function FontClosure() {
return builder.toArray();
},
/**
* Builds a char code to unicode map based on section 9.10 of the spec.
* @param {Object} properties Font properties object.
* @return {Object} A ToUnicodeMap object.
*/
buildToUnicode: function Font_buildToUnicode(properties) {
// Section 9.10.2 Mapping Character Codes to Unicode Values
if (properties.toUnicode && properties.toUnicode.length !== 0) {
return properties.toUnicode;
}
// According to the spec if the font is a simple font we should only map
// to unicode if the base encoding is MacRoman, MacExpert, or WinAnsi or
// the differences array only contains adobe standard or symbol set names,
// in pratice it seems better to always try to create a toUnicode
// map based of the default encoding.
var toUnicode, charcode;
if (!properties.composite /* is simple font */) {
toUnicode = [];
var encoding = properties.defaultEncoding.slice();
var baseEncodingName = properties.baseEncodingName;
// Merge in the differences array.
var differences = properties.differences;
for (charcode in differences) {
encoding[charcode] = differences[charcode];
}
var glyphsUnicodeMap = getGlyphsUnicode();
for (charcode in encoding) {
// a) Map the character code to a character name.
var glyphName = encoding[charcode];
// b) Look up the character name in the Adobe Glyph List (see the
// Bibliography) to obtain the corresponding Unicode value.
if (glyphName === '') {
continue;
} else if (glyphsUnicodeMap[glyphName] === undefined) {
// (undocumented) c) Few heuristics to recognize unknown glyphs
// NOTE: Adobe Reader does not do this step, but OSX Preview does
var code = 0;
switch (glyphName[0]) {
case 'G': // Gxx glyph
if (glyphName.length === 3) {
code = parseInt(glyphName.substr(1), 16);
}
break;
case 'g': // g00xx glyph
if (glyphName.length === 5) {
code = parseInt(glyphName.substr(1), 16);
}
break;
case 'C': // Cddd glyph
case 'c': // cddd glyph
if (glyphName.length >= 3) {
code = +glyphName.substr(1);
}
break;
default:
// 'uniXXXX'/'uXXXX{XX}' glyphs
var unicode = getUnicodeForGlyph(glyphName, glyphsUnicodeMap);
if (unicode !== -1) {
code = unicode;
}
}
if (code) {
// If |baseEncodingName| is one the predefined encodings,
// and |code| equals |charcode|, using the glyph defined in the
// baseEncoding seems to yield a better |toUnicode| mapping
// (fixes issue 5070).
if (baseEncodingName && code === +charcode) {
var baseEncoding = getEncoding(baseEncodingName);
if (baseEncoding && (glyphName = baseEncoding[charcode])) {
toUnicode[charcode] =
String.fromCharCode(glyphsUnicodeMap[glyphName]);
continue;
}
}
toUnicode[charcode] = String.fromCharCode(code);
}
continue;
}
toUnicode[charcode] =
String.fromCharCode(glyphsUnicodeMap[glyphName]);
}
return new ToUnicodeMap(toUnicode);
}
// If the font is a composite font that uses one of the predefined CMaps
// listed in Table 118 (except Identity–H and Identity–V) or whose
// descendant CIDFont uses the Adobe-GB1, Adobe-CNS1, Adobe-Japan1, or
// Adobe-Korea1 character collection:
if (properties.composite && (
(properties.cMap.builtInCMap &&
!(properties.cMap instanceof IdentityCMap)) ||
(properties.cidSystemInfo.registry === 'Adobe' &&
(properties.cidSystemInfo.ordering === 'GB1' ||
properties.cidSystemInfo.ordering === 'CNS1' ||
properties.cidSystemInfo.ordering === 'Japan1' ||
properties.cidSystemInfo.ordering === 'Korea1')))) {
// Then:
// a) Map the character code to a character identifier (CID) according
// to the font’s CMap.
// b) Obtain the registry and ordering of the character collection used
// by the font’s CMap (for example, Adobe and Japan1) from its
// CIDSystemInfo dictionary.
var registry = properties.cidSystemInfo.registry;
var ordering = properties.cidSystemInfo.ordering;
// c) Construct a second CMap name by concatenating the registry and
// ordering obtained in step (b) in the format registry–ordering–UCS2
// (for example, Adobe–Japan1–UCS2).
var ucs2CMapName = new Name(registry + '-' + ordering + '-UCS2');
// d) Obtain the CMap with the name constructed in step (c) (available
// from the ASN Web site; see the Bibliography).
var ucs2CMap = CMapFactory.create(ucs2CMapName,
{ url: PDFJS.cMapUrl, packed: PDFJS.cMapPacked }, null);
var cMap = properties.cMap;
toUnicode = [];
cMap.forEach(function(charcode, cid) {
assert(cid <= 0xffff, 'Max size of CID is 65,535');
// e) Map the CID obtained in step (a) according to the CMap obtained
// in step (d), producing a Unicode value.
var ucs2 = ucs2CMap.lookup(cid);
if (ucs2) {
toUnicode[charcode] =
String.fromCharCode((ucs2.charCodeAt(0) << 8) +
ucs2.charCodeAt(1));
}
});
return new ToUnicodeMap(toUnicode);
}
// The viewer's choice, just use an identity map.
return new IdentityToUnicodeMap(properties.firstChar,
properties.lastChar);
},
get spaceWidth() {
if ('_shadowWidth' in this) {
return this._shadowWidth;