private CompactFontFormatCidFont ReadCidFont(CompactFontFormatData data, CompactFontFormatTopLevelDictionary topLevelDictionary,
                                                     int numberOfGlyphs,
                                                     IReadOnlyList <string> stringIndex,
                                                     CompactFontFormatPrivateDictionary privateDictionary,
                                                     ICompactFontFormatCharset charset,
                                                     CompactFontFormatIndex globalSubroutines,
                                                     CompactFontFormatIndex localSubroutinesTop,
                                                     CompactFontFormatIndex charStringIndex)
        {
            var offset = topLevelDictionary.CidFontOperators.FontDictionaryArray;

            data.Seek(offset);

            var fontDict = CompactFontFormatIndexReader.ReadDictionaryData(data);

            var privateDictionaries  = new List <CompactFontFormatPrivateDictionary>();
            var fontDictionaries     = new List <CompactFontFormatTopLevelDictionary>();
            var fontLocalSubroutines = new List <CompactFontFormatIndex>();

            foreach (var index in fontDict)
            {
                var topLevelDictionaryCid = topLevelDictionaryReader.Read(new CompactFontFormatData(index), stringIndex);

                if (!topLevelDictionaryCid.PrivateDictionaryLocation.HasValue)
                {
                    throw new InvalidFontFormatException("The CID keyed Compact Font Format font did not contain a private dictionary for the font dictionary.");
                }

                var privateDictionaryBytes = data.SnapshotPortion(topLevelDictionaryCid.PrivateDictionaryLocation.Value.Offset,
                                                                  topLevelDictionaryCid.PrivateDictionaryLocation.Value.Size);

                var privateDictionaryCid = privateDictionaryReader.Read(privateDictionaryBytes, stringIndex);

                // CFFParser.java line 625 - read the local subroutines.
                if (privateDictionaryCid.LocalSubroutineOffset.HasValue && privateDictionaryCid.LocalSubroutineOffset.Value > 0)
                {
                    data.Seek(topLevelDictionaryCid.PrivateDictionaryLocation.Value.Offset + privateDictionaryCid.LocalSubroutineOffset.Value);
                    var localSubroutines = CompactFontFormatIndexReader.ReadDictionaryData(data);
                    fontLocalSubroutines.Add(localSubroutines);
                }
                else
                {
                    fontLocalSubroutines.Add(null);
                }

                fontDictionaries.Add(topLevelDictionaryCid);
                privateDictionaries.Add(privateDictionaryCid);
            }

            data.Seek(topLevelDictionary.CidFontOperators.FontDictionarySelect);

            var format = data.ReadCard8();

            ICompactFontFormatFdSelect fdSelect;

            switch (format)
            {
            case 0:
            {
                fdSelect = ReadFormat0FdSelect(data, numberOfGlyphs, topLevelDictionary.CidFontOperators.Ros);
                break;
            }

            case 3:
            {
                fdSelect = ReadFormat3FdSelect(data, topLevelDictionary.CidFontOperators.Ros);
                break;
            }

            default:
                throw new InvalidFontFormatException($"Invalid Font Dictionary Select format: {format}.");
            }

            var subroutineSelector = new CompactFontFormatSubroutinesSelector(globalSubroutines, localSubroutinesTop,
                                                                              fdSelect, fontLocalSubroutines);

            var charStrings = ReadCharStrings(data, topLevelDictionary, charStringIndex, subroutineSelector, charset);

            var union = Union <Type1CharStrings, Type2CharStrings> .Two(charStrings);

            return(new CompactFontFormatCidFont(topLevelDictionary, privateDictionary, charset, union,
                                                fontDictionaries, privateDictionaries, fdSelect));
        }
        public CompactFontFormatFont Parse(CompactFontFormatData data, string name, IReadOnlyList <byte> topDictionaryIndex, IReadOnlyList <string> stringIndex,
                                           CompactFontFormatIndex globalSubroutineIndex)
        {
            var individualData = new CompactFontFormatData(topDictionaryIndex.ToArray());

            var topDictionary = topLevelDictionaryReader.Read(individualData, stringIndex);

            var privateDictionary = CompactFontFormatPrivateDictionary.GetDefault();

            if (topDictionary.PrivateDictionaryLocation.HasValue && topDictionary.PrivateDictionaryLocation.Value.Size > 0)
            {
                var privateDictionaryBytes = data.SnapshotPortion(topDictionary.PrivateDictionaryLocation.Value.Offset,
                                                                  topDictionary.PrivateDictionaryLocation.Value.Size);

                privateDictionary = privateDictionaryReader.Read(privateDictionaryBytes, stringIndex);
            }

            if (topDictionary.CharStringsOffset < 0)
            {
                throw new InvalidOperationException("Expected CFF to contain a CharString offset.");
            }

            var localSubroutines = CompactFontFormatIndex.None;

            if (privateDictionary.LocalSubroutineOffset.HasValue && topDictionary.PrivateDictionaryLocation.HasValue)
            {
                data.Seek(privateDictionary.LocalSubroutineOffset.Value + topDictionary.PrivateDictionaryLocation.Value.Offset);

                localSubroutines = CompactFontFormatIndexReader.ReadDictionaryData(data);
            }

            data.Seek(topDictionary.CharStringsOffset);

            var charStringIndex = CompactFontFormatIndexReader.ReadDictionaryData(data);

            ICompactFontFormatCharset charset;

            if (topDictionary.CharSetOffset >= 0)
            {
                var charsetId = topDictionary.CharSetOffset;
                if (!topDictionary.IsCidFont && charsetId == 0)
                {
                    charset = CompactFontFormatIsoAdobeCharset.Value;
                }
                else if (!topDictionary.IsCidFont && charsetId == 1)
                {
                    charset = CompactFontFormatExpertCharset.Value;
                }
                else if (!topDictionary.IsCidFont && charsetId == 2)
                {
                    charset = CompactFontFormatExpertSubsetCharset.Value;
                }
                else
                {
                    charset = ReadCharset(data, topDictionary, charStringIndex, stringIndex);
                }
            }
            else
            {
                if (topDictionary.IsCidFont)
                {
                    // a CID font with no charset does not default to any predefined charset
                    charset = new CompactFontFormatEmptyCharset(charStringIndex.Count);
                }
                else
                {
                    charset = CompactFontFormatIsoAdobeCharset.Value;
                }
            }

            if (topDictionary.IsCidFont)
            {
                return(ReadCidFont(data, topDictionary, charStringIndex.Count, stringIndex, privateDictionary,
                                   charset,
                                   globalSubroutineIndex,
                                   localSubroutines,
                                   charStringIndex));
            }

            var encoding = topDictionary.EncodingOffset;

            Encoding fontEncoding = null;

            if (encoding != CompactFontFormatTopLevelDictionary.UnsetOffset)
            {
                if (encoding == 0)
                {
                    fontEncoding = CompactFontFormatStandardEncoding.Instance;
                }
                else if (encoding == 1)
                {
                    fontEncoding = CompactFontFormatExpertEncoding.Instance;
                }
                else
                {
                    data.Seek(encoding);
                    fontEncoding = CompactFontFormatEncodingReader.ReadEncoding(data, charset, stringIndex);
                }
            }

            var subroutineSelector = new CompactFontFormatSubroutinesSelector(globalSubroutineIndex, localSubroutines);

            var charStrings = ReadCharStrings(data, topDictionary, charStringIndex, subroutineSelector, charset);

            return(new CompactFontFormatFont(topDictionary, privateDictionary, charset, Union <Type1CharStrings, Type2CharStrings> .Two(charStrings), fontEncoding));
        }
Пример #3
0
        public CompactFontFormatFont Parse(CompactFontFormatData data, string name, IReadOnlyList <byte> topDictionaryIndex, IReadOnlyList <string> stringIndex,
                                           CompactFontFormatIndex globalSubroutineIndex)
        {
            var individualData = new CompactFontFormatData(topDictionaryIndex.ToArray());

            var topDictionary = topLevelDictionaryReader.Read(individualData, stringIndex);

            var privateDictionary = CompactFontFormatPrivateDictionary.GetDefault();

            if (topDictionary.PrivateDictionaryLocation.HasValue)
            {
                var privateDictionaryBytes = data.SnapshotPortion(topDictionary.PrivateDictionaryLocation.Value.Offset,
                                                                  topDictionary.PrivateDictionaryLocation.Value.Size);

                privateDictionary = privateDictionaryReader.Read(privateDictionaryBytes, stringIndex);
            }

            if (topDictionary.CharStringsOffset < 0)
            {
                throw new InvalidOperationException("Expected CFF to contain a CharString offset.");
            }

            var localSubroutines = CompactFontFormatIndex.None;

            if (privateDictionary.LocalSubroutineOffset.HasValue && topDictionary.PrivateDictionaryLocation.HasValue)
            {
                data.Seek(privateDictionary.LocalSubroutineOffset.Value + topDictionary.PrivateDictionaryLocation.Value.Offset);

                localSubroutines = indexReader.ReadDictionaryData(data);
            }

            data.Seek(topDictionary.CharStringsOffset);

            var charStringIndex = indexReader.ReadDictionaryData(data);

            ICompactFontFormatCharset charset = null;

            if (topDictionary.IsCidFont && topDictionary.CharSetOffset >= 0 && topDictionary.CharSetOffset <= 2)
            {
                switch (topDictionary.CharSetOffset)
                {
                case 0:
                    charset = CompactFontFormatIsoAdobeCharset.Value;
                    break;

                case 1:
                    charset = CompactFontFormatExpertCharset.Value;
                    break;

                case 2:
                    charset = CompactFontFormatExpertSubsetCharset.Value;
                    break;
                }
            }
            else
            {
                data.Seek(topDictionary.CharSetOffset);

                var format = data.ReadCard8();

                switch (format)
                {
                case 0:
                {
                    var glyphToNamesAndStringId = new List <(int glyphId, int stringId, string name)>();

                    for (var glyphId = 1; glyphId < charStringIndex.Count; glyphId++)
                    {
                        var stringId = data.ReadSid();
                        glyphToNamesAndStringId.Add((glyphId, stringId, ReadString(stringId, stringIndex)));
                    }

                    charset = new CompactFontFormatFormat0Charset(glyphToNamesAndStringId);

                    break;
                }

                case 1:
                case 2:
                {
                    var glyphToNamesAndStringId = new List <(int glyphId, int stringId, string name)>();

                    for (var glyphId = 1; glyphId < charStringIndex.Count; glyphId++)
                    {
                        var firstSid      = data.ReadSid();
                        var numberInRange = format == 1 ? data.ReadCard8() : data.ReadCard16();

                        glyphToNamesAndStringId.Add((glyphId, firstSid, ReadString(firstSid, stringIndex)));
                        for (var i = 0; i < numberInRange; i++)
                        {
                            glyphId++;
                            var sid = firstSid + i + 1;
                            glyphToNamesAndStringId.Add((glyphId, sid, ReadString(sid, stringIndex)));
                        }
                    }

                    if (format == 1)
                    {
                        charset = new CompactFontFormatFormat1Charset(glyphToNamesAndStringId);
                    }
                    else
                    {
                        charset = new CompactFontFormatFormat2Charset(glyphToNamesAndStringId);
                    }

                    break;
                }

                default:
                    throw new InvalidOperationException($"Unrecognized format for the Charset table in a CFF font. Got: {format}.");
                }
            }

            data.Seek(topDictionary.CharStringsOffset);

            Type2CharStrings charStrings;

            switch (topDictionary.CharStringType)
            {
            case CompactFontFormatCharStringType.Type1:
                throw new NotImplementedException();

            case CompactFontFormatCharStringType.Type2:
                charStrings = Type2CharStringParser.Parse(charStringIndex, localSubroutines, globalSubroutineIndex, charset);
                break;

            default:
                throw new ArgumentOutOfRangeException($"Unexpected CharString type in CFF font: {topDictionary.CharStringType}.");
            }

            return(new CompactFontFormatFont(topDictionary, privateDictionary, charset, Union <Type1CharStrings, Type2CharStrings> .Two(charStrings)));
        }