public static CmapTable Read(FontStreamReader reader, OffsetTable.Entry entry)
{
reader.Seek(entry);
var version = reader.ReadUInt16();
if (version != 0)
{
throw new FormatException($"Unexpected version number in cmap table: {version}, expecting 0");
}
var numberOfSubtables = reader.ReadUInt16();
var subtables = new Dictionary <Tuple <ushort, ushort>, CmapFormat>();
for (var i = 0; i < numberOfSubtables; i++)
{
var platformId = reader.ReadUInt16();
var platformSpecificId = reader.ReadUInt16();
var relOffset = reader.ReadUInt32();
var offset = entry.Offset + relOffset;
var subtable = ReadSubtable(reader, platformId, platformSpecificId, offset);
subtables.Add(Tuple.Create(platformId, platformSpecificId), subtable);
}
return(new CmapTable(version, subtables));
}
public static FpgmTable Read(FontStreamReader reader, OffsetTable.Entry entry)
{
reader.Seek(entry);
var instructions = reader.ReadArray <byte>(entry.Length, r => r.ReadUInt8);
return(new FpgmTable(instructions));
}
public static LocaTable Read(Font font, FontStreamReader reader, OffsetTable.Entry entry)
{
reader.Seek(entry);
var length = entry.Length;
var format = font.HeadTable.IndexToLocFormat;
switch (format)
{
case IndexToLocFormat.Short:
return(new LocaTable(reader.ReadArray <uint>(length / sizeof(ushort), r => (() => r.ReadUInt16()))));
case IndexToLocFormat.Long:
return(new LocaTable(reader.ReadArray <uint>(length / sizeof(uint), r => r.ReadUInt32)));
default: throw new FormatException($"Invalid IndexToLocFormat: {format}");
}
}
public static HeadTable Read(FontStreamReader reader, OffsetTable.Entry entry)
{
reader.Seek(entry);
var version = reader.ReadFixed();
var fontRevision = reader.ReadFixed();
//TODO
var checkSumAdjustment = reader.ReadUInt32();
var magicNumber = reader.ReadUInt32(); // 0x5F0F3CF5
if (magicNumber != 0x5F0F3CF5)
{
throw new FormatException($"Invalid magic number in header: 0x{magicNumber:X}, expecting 0x5F0F3CF5");
}
var flags = reader.ReadUInt16(); // bitflags
var unitsPerEm = reader.ReadUInt16(); // 64-16384
if (unitsPerEm < 64 || unitsPerEm > 16384)
{
throw new FormatException($"Invalid units per em in header: {unitsPerEm:X}, expecting a value between 64 and 16384");
}
var created = reader.ReadLongDateTime();
var modified = reader.ReadLongDateTime();
var xMin = reader.ReadFWord();
var yMin = reader.ReadFWord();
var xMax = reader.ReadFWord();
var yMax = reader.ReadFWord();
var macStyle = (MacStyle)reader.ReadUInt16(); // bitflags
var lowestRecPPEM = reader.ReadUInt16();
var fontDirectionHint = reader.ReadUInt16();
var indexToLocFormat = (IndexToLocFormat)reader.ReadUInt16(); // 0 = short, 1 = long
var glyphDataFormat = (GlyphDataFormat)reader.ReadUInt16(); // 0 = current
return(new HeadTable(version, fontRevision, flags, unitsPerEm, created, modified, xMin, yMin, xMax, yMax, macStyle, lowestRecPPEM, fontDirectionHint, indexToLocFormat, glyphDataFormat));
}
public static GlyfTable Read(FontStreamReader reader, OffsetTable.Entry entry)
{
reader.Seek(entry);
var glyphs = new List <Glyph>();
while (reader.Position < entry.Offset + entry.Length)
{
glyphs.Add(ReadGlyph(reader));
while ((reader.Position & 1) != 0)
{
reader.ReadUInt8();
}
}
if (reader.Position > entry.Offset + entry.Length)
{
throw new Exception("Overflow?");
}
return(new GlyfTable(glyphs));
}
private static CmapFormat ReadSubtable(FontStreamReader reader, ushort platformId, ushort platformSpecificId, uint offset)
{
reader.Push();
reader.Seek(offset, SeekOrigin.Begin);
var format = reader.ReadUInt16();
CmapFormat result;
switch (format)
{
case 0: result = CmapFormat0.Read(reader, platformId, platformSpecificId); break;
case 2: result = CmapFormat2.Read(reader, platformId, platformSpecificId); break;
case 4: result = CmapFormat4.Read(reader, platformId, platformSpecificId); break;
case 6: result = CmapFormat6.Read(reader, platformId, platformSpecificId); break;
case 8: result = CmapFormat8.Read(reader, platformId, platformSpecificId); break;
case 10: result = CmapFormat10.Read(reader, platformId, platformSpecificId); break;
case 12: result = CmapFormat12.Read(reader, platformId, platformSpecificId); break;
case 13: result = CmapFormat13.Read(reader, platformId, platformSpecificId); break;
case 14: result = CmapFormat14.Read(reader, platformId, platformSpecificId); break;
default: throw new FormatException($"Unexpected cmap subtable format: {format}");
}
reader.Pop();
return(result);
}