/// <summary>
/// Reads indexed string data.
/// </summary>
private static string[] ReadStringIndex(CompactFontFormatData data)
{
var index = CompactFontFormatIndexReader.ReadIndex(data);
if (index.Length == 0)
{
return(EmptyArray <string> .Instance);
}
var count = index.Length - 1;
var result = new string[count];
for (var i = 0; i < count; i++)
{
var length = index[i + 1] - index[i];
if (length < 0)
{
throw new InvalidOperationException($"Negative object length {length} at {i}. Current position: {data.Position}.");
}
result[i] = data.ReadString(length, OtherEncodings.Iso88591);
}
return(result);
}
public CompactFontFormatIndividualFontParser(CompactFontFormatIndexReader indexReader,
CompactFontFormatTopLevelDictionaryReader topLevelDictionaryReader,
CompactFontFormatPrivateDictionaryReader privateDictionaryReader)
{
this.indexReader = indexReader;
this.topLevelDictionaryReader = topLevelDictionaryReader;
this.privateDictionaryReader = privateDictionaryReader;
}
/// <summary>
/// Read the Compact Font Format font from the input data.
/// </summary>
public static CompactFontFormatFontCollection Parse(CompactFontFormatData data)
{
var tag = ReadTag(data);
switch (tag)
{
// An OpenType font containing CFF data.
case TagOtto:
throw new NotSupportedException("Currently tagged CFF data is not supported.");
case TagTtcf:
throw new NotSupportedException("True Type Collection fonts are not currently supported.");
case TagTtfonly:
throw new NotSupportedException("OpenType fonts containing a true type font are not currently supported.");
default:
data.Seek(0);
break;
}
var header = ReadHeader(data);
var fontNames = ReadStringIndex(data);
var topLevelDictionaryIndex = CompactFontFormatIndexReader.ReadDictionaryData(data);
var stringIndex = ReadStringIndex(data);
var globalSubroutineIndex = CompactFontFormatIndexReader.ReadDictionaryData(data);
var fonts = new Dictionary <string, CompactFontFormatFont>();
var individualFontParser = new CompactFontFormatIndividualFontParser(new CompactFontFormatTopLevelDictionaryReader(), new CompactFontFormatPrivateDictionaryReader());
for (var i = 0; i < fontNames.Length; i++)
{
var fontName = fontNames[i];
fonts[fontName] = individualFontParser.Parse(data, fontName, topLevelDictionaryIndex[i], stringIndex, globalSubroutineIndex);
}
return(new CompactFontFormatFontCollection(header, fonts));
}
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));
}
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 CompactFontFormatParser(CompactFontFormatIndividualFontParser individualFontParser, CompactFontFormatIndexReader indexReader)
{
this.individualFontParser = individualFontParser;
this.indexReader = indexReader;
}