FontCollectionHeader ReadTTCHeader(ByteOrderSwappingBinaryReader input) { //https://docs.microsoft.com/en-us/typography/opentype/spec/otff#ttc-header //TTC Header Version 1.0: //Type Name Description //TAG ttcTag Font Collection ID string: 'ttcf' (used for fonts with CFF or CFF2 outlines as well as TrueType outlines) //uint16 majorVersion Major version of the TTC Header, = 1. //uint16 minorVersion Minor version of the TTC Header, = 0. //uint32 numFonts Number of fonts in TTC //Offset32 offsetTable[numFonts] Array of offsets to the OffsetTable for each font from the beginning of the file //TTC Header Version 2.0: //Type Name Description //TAG ttcTag Font Collection ID string: 'ttcf' //uint16 majorVersion Major version of the TTC Header, = 2. //uint16 minorVersion Minor version of the TTC Header, = 0. //uint32 numFonts Number of fonts in TTC //Offset32 offsetTable[numFonts] Array of offsets to the OffsetTable for each font from the beginning of the file //uint32 dsigTag Tag indicating that a DSIG table exists, 0x44534947 ('DSIG') (null if no signature) //uint32 dsigLength The length (in bytes) of the DSIG table (null if no signature) //uint32 dsigOffset The offset (in bytes) of the DSIG table from the beginning of the TTC file (null if no signature) var ttcHeader = new FontCollectionHeader(); ttcHeader.majorVersion = input.ReadUInt16(); ttcHeader.minorVersion = input.ReadUInt16(); uint numFonts = input.ReadUInt32(); int[] offsetTables = new int[numFonts]; for (uint i = 0; i < numFonts; ++i) { offsetTables[i] = input.ReadInt32(); } ttcHeader.numFonts = numFonts; ttcHeader.offsetTables = offsetTables; // if (ttcHeader.majorVersion == 2) { ttcHeader.dsigTag = input.ReadUInt32(); ttcHeader.dsigLength = input.ReadUInt32(); ttcHeader.dsigOffset = input.ReadUInt32(); if (ttcHeader.dsigTag == 0x44534947) { //Tag indicating that a DSIG table exists //TODO: goto DSIG add read signature } } return(ttcHeader); }
/// <summary> /// read only name entry /// </summary> /// <param name="stream"></param> /// <returns></returns> public PreviewFontInfo ReadPreview(Stream stream) { //var little = BitConverter.IsLittleEndian; using (var input = new ByteOrderSwappingBinaryReader(stream)) { ushort majorVersion = input.ReadUInt16(); ushort minorVersion = input.ReadUInt16(); if (KnownFontFiles.IsTtcf(majorVersion, minorVersion)) { //this font stream is 'The Font Collection' FontCollectionHeader ttcHeader = ReadTTCHeader(input); PreviewFontInfo[] members = new PreviewFontInfo[ttcHeader.numFonts]; for (uint i = 0; i < ttcHeader.numFonts; ++i) { input.BaseStream.Seek(ttcHeader.offsetTables[i], SeekOrigin.Begin); PreviewFontInfo member = members[i] = ReadActualFontPreview(input, false); member.ActualStreamOffset = ttcHeader.offsetTables[i]; } return(new PreviewFontInfo(BuildTtcfName(members), members)); } else if (KnownFontFiles.IsWoff(majorVersion, minorVersion)) { //check if we enable woff or not WebFont.WoffReader woffReader = new WebFont.WoffReader(); input.BaseStream.Position = 0; return(woffReader.ReadPreview(input)); } else if (KnownFontFiles.IsWoff2(majorVersion, minorVersion)) { //check if we enable woff2 or not WebFont.Woff2Reader woffReader = new WebFont.Woff2Reader(); input.BaseStream.Position = 0; return(woffReader.ReadPreview(input)); } else { return(ReadActualFontPreview(input, true));//skip version data (majorVersion, minorVersion) } } }