private static Type2CharStrings ReadCharStrings(CompactFontFormatData data, CompactFontFormatTopLevelDictionary topDictionary,
                                                        CompactFontFormatIndex charStringIndex,
                                                        CompactFontFormatSubroutinesSelector subroutinesSelector,
                                                        ICompactFontFormatCharset charset)
        {
            data.Seek(topDictionary.CharStringsOffset);

            switch (topDictionary.CharStringType)
            {
            case CompactFontFormatCharStringType.Type1:
                throw new NotImplementedException("Type 1 CharStrings are not currently supported in CFF font.");

            case CompactFontFormatCharStringType.Type2:
                return(Type2CharStringParser.Parse(charStringIndex, subroutinesSelector, charset));

            default:
                throw new ArgumentOutOfRangeException($"Unexpected CharString type in CFF font: {topDictionary.CharStringType}.");
            }
        }
Ejemplo n.º 2
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        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 = indexReader.ReadDictionaryData(data);
            }

            data.Seek(topDictionary.CharStringsOffset);

            var charStringIndex = indexReader.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;
                }
            }

            data.Seek(topDictionary.CharStringsOffset);

            Type2CharStrings charStrings;

            switch (topDictionary.CharStringType)
            {
            case CompactFontFormatCharStringType.Type1:
                throw new NotImplementedException("Type 1 CharStrings are not currently supported in CFF font.");

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

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

            if (topDictionary.IsCidFont)
            {
                return(ReadCidFont(data, topDictionary, charStringIndex.Count, stringIndex, privateDictionary, charset, Union <Type1CharStrings, Type2CharStrings> .Two(charStrings)));
            }

            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);
                }
            }

            return(new CompactFontFormatFont(topDictionary, privateDictionary, charset, Union <Type1CharStrings, Type2CharStrings> .Two(charStrings), fontEncoding));
        }
Ejemplo n.º 3
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        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)));
        }