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Use built in CMaps and unify the glyph mapping.

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This commit is contained in:
Brendan Dahl 2014-02-11 10:27:09 -08:00
parent 7be2d6db58
commit b5b94a4af3
16 changed files with 891 additions and 1130 deletions
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118
src/core/evaluator.js
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@ -828,41 +828,21 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
}
// Based on 9.6.6 of the spec the encoding can come from multiple places
// but should be prioritized in the following order:
// 1. Encoding dictionary
// 2. Encoding within font file (Type1 or Type1C)
// 3. Default (depends on font type)
// Differences applied to the above.
// Note: we don't fill in the encoding from the font file(2) here but use
// the flag overridableEncoding to signal that the font can override the
// encoding if it has one built in.
var overridableEncoding = true;
var hasEncoding = false;
var flags = properties.flags;
// and depends on the font type. The base encoding and differences are
// read here, but the encoding that is actually used is chosen during
// glyph mapping in the font.
// TODO: Loading the built in encoding in the font would allow the
// differences to be merged in here not require us to hold on to it.
var differences = [];
var baseEncoding = properties.type === 'TrueType' ?
Encodings.WinAnsiEncoding :
Encodings.StandardEncoding;
// The Symbolic attribute can be misused for regular fonts
// Heuristic: we have to check if the font is a standard one and has
// Symbolic font name
if (!!(flags & FontFlags.Symbolic)) {
baseEncoding = !properties.file && /Symbol/i.test(properties.name) ?
Encodings.SymbolSetEncoding : Encodings.MacRomanEncoding;
}
var baseEncodingName = null;
if (dict.has('Encoding')) {
var encoding = dict.get('Encoding');
if (isDict(encoding)) {
var baseName = encoding.get('BaseEncoding');
if (baseName) {
overridableEncoding = false;
hasEncoding = true;
baseEncoding = Encodings[baseName.name];
}
baseEncodingName = encoding.get('BaseEncoding');
baseEncodingName = isName(baseEncodingName) ? baseEncodingName.name :
null;
// Load the differences between the base and original
if (encoding.has('Differences')) {
hasEncoding = true;
var diffEncoding = encoding.get('Differences');
var index = 0;
for (var j = 0, jj = diffEncoding.length; j < jj; j++) {
@ -874,38 +854,44 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
}
}
} else if (isName(encoding)) {
overridableEncoding = false;
hasEncoding = true;
var currentEncoding = Encodings[encoding.name];
// Some bad PDF files contain fonts whose encoding name is not among
// the predefined encodings, causing baseEncoding to be undefined.
// In this case, fallback to using the baseEncoding as defined above
// and let the font override the encoding if one is available.
if (currentEncoding) {
baseEncoding = currentEncoding;
} else {
overridableEncoding = true;
}
baseEncodingName = encoding.name;
} else {
error('Encoding is not a Name nor a Dict');
}
// According to table 114 if the encoding is a named encoding it must be
// one of these predefined encodings.
if ((baseEncodingName !== 'MacRomanEncoding' &&
baseEncodingName !== 'MacExpertEncoding' &&
baseEncodingName !== 'WinAnsiEncoding')) {
baseEncodingName = null;
}
}
if (baseEncodingName) {
properties.defaultEncoding = Encodings[baseEncodingName].slice();
} else {
var encoding = properties.type === 'TrueType' ?
Encodings.WinAnsiEncoding :
Encodings.StandardEncoding;
// The Symbolic attribute can be misused for regular fonts
// Heuristic: we have to check if the font is a standard one also
if (!!(properties.flags & FontFlags.Symbolic)) {
encoding = !properties.file && /Symbol/i.test(properties.name) ?
Encodings.SymbolSetEncoding : Encodings.MacRomanEncoding;
}
properties.defaultEncoding = encoding;
}
properties.differences = differences;
properties.baseEncoding = baseEncoding;
properties.hasEncoding = hasEncoding;
properties.overridableEncoding = overridableEncoding;
properties.baseEncodingName = baseEncodingName;
properties.dict = dict;
},
readToUnicode: function PartialEvaluator_readToUnicode(toUnicode, xref,
properties) {
readToUnicode: function PartialEvaluator_readToUnicode(toUnicode) {
var cmapObj = toUnicode;
var charToUnicode = [];
if (isName(cmapObj)) {
var isIdentityMap = cmapObj.name.substr(0, 9) == 'Identity-';
if (!isIdentityMap)
error('ToUnicode file cmap translation not implemented');
return CMapFactory.create(cmapObj).map;
} else if (isStream(cmapObj)) {
var cmap = CMapFactory.create(cmapObj).map;
// Convert UTF-16BE
@ -927,7 +913,7 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
});
return cmap;
}
return charToUnicode;
return null;
},
readCidToGidMap: function PartialEvaluator_readCidToGidMap(cidToGidStream) {
// Extract the encoding from the CIDToGIDMap
@ -1006,7 +992,8 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
if (isName(baseFontName)) {
var metrics = this.getBaseFontMetrics(baseFontName.name);
glyphsWidths = metrics.widths;
glyphsWidths = this.buildCharCodeToWidth(metrics.widths,
properties);
defaultWidth = metrics.defaultWidth;
}
}
@ -1074,6 +1061,25 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
};
},
buildCharCodeToWidth: function PartialEvaluator_bulildCharCodeToWidth(
widthsByGlyphName, properties) {
var widths = Object.create(null);
var differences = properties.differences;
var encoding = properties.defaultEncoding;
for (var charCode = 0; charCode < 256; charCode++) {
if (charCode in differences &&
widthsByGlyphName[differences[charCode]]) {
widths[charCode] = widthsByGlyphName[differences[charCode]];
continue;
}
if (charCode in encoding && widthsByGlyphName[encoding[charCode]]) {
widths[charCode] = widthsByGlyphName[encoding[charCode]];
continue;
}
}
return widths;
},
translateFont: function PartialEvaluator_translateFont(dict,
xref) {
var baseDict = dict;
@ -1135,6 +1141,8 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
lastChar: maxCharIndex
};
this.extractDataStructures(dict, dict, xref, properties);
properties.widths = this.buildCharCodeToWidth(metrics.widths,
properties);
return new Font(baseFontName, null, properties);
}
@ -1212,12 +1220,12 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
var cidEncoding = baseDict.get('Encoding');
if (isName(cidEncoding)) {
properties.cidEncoding = cidEncoding.name;
properties.vertical = /-V$/.test(cidEncoding.name);
}
properties.cmap = CMapFactory.create(cidEncoding);
properties.cMap = CMapFactory.create(cidEncoding, PDFJS.cMapUrl, null);
properties.vertical = properties.cMap.vertical;
}
this.extractWidths(dict, xref, descriptor, properties);
this.extractDataStructures(dict, baseDict, xref, properties);
this.extractWidths(dict, xref, descriptor, properties);
if (type.name === 'Type3') {
properties.coded = true;