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 CmapFormat Read(FontStreamReader reader, ushort platformId, ushort platformSpecificId)
{
var length = reader.ReadUInt16();
var language = reader.ReadUInt16();
var glyphIndexArray = reader.ReadArray <byte>(256, r => r.ReadUInt8);
return(new CmapFormat0(language, glyphIndexArray));
}
private static Glyph ReadGlyph(FontStreamReader reader)
{
var numberOfContours = reader.ReadInt16();
var isCompound = numberOfContours < 0;
var xMin = reader.ReadFWord();
var yMin = reader.ReadFWord();
var xMax = reader.ReadFWord();
var yMax = reader.ReadFWord();
if (isCompound)
{
return(ReadCompoundGlyph(reader, xMin, yMin, xMax, yMax));
}
return(ReadSimpleGlyph(reader, numberOfContours, xMin, yMin, xMax, yMax));
}
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 CmapFormat Read(FontStreamReader reader, ushort platformId, ushort platformSpecificId)
{
uint length = reader.ReadUInt16();
var language = reader.ReadUInt16();
length -= 3 * sizeof(ushort);
var segCount = (ushort)(reader.ReadUInt16() / 2); // stored as 2 * segCount
var searchRange = reader.ReadUInt16();
var entrySelector = reader.ReadUInt16();
var rangeShift = reader.ReadUInt16();
length -= 4 * sizeof(ushort);
var endCode = reader.ReadArray <ushort>(segCount, r => r.ReadUInt16);
if (endCode[endCode.Length - 1] != 0xffff)
{
throw new FormatException($"Unexpected last endCode: 0x{endCode[endCode.Length - 1]:X}, expecting 0xffff");
}
var reservedPad = reader.ReadUInt16(); // 0
if (reservedPad != 0)
{
throw new FormatException($"Unexpected value for reservedPad: {reservedPad}, expecting 0");
}
length -= (ushort)(segCount * sizeof(ushort) + 1);
var startCode = reader.ReadArray <ushort>(segCount, r => r.ReadUInt16);
var idDelta = reader.ReadArray <ushort>(segCount, r => r.ReadUInt16);
var idRangeOffset = reader.ReadArray <ushort>(segCount, r => r.ReadUInt16);
length -= (ushort)(3 * segCount * sizeof(ushort));
var glyphIndexArray = reader.ReadArray <ushort>(length / sizeof(ushort), r => r.ReadUInt16);
return(new CmapFormat4(language, startCode, endCode, idDelta, idRangeOffset, glyphIndexArray));
}
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);
}
public static CmapFormat Read(FontStreamReader reader, ushort platformId, ushort platformSpecificId)
{
throw new NotImplementedException();
}
private static Glyph ReadCompoundGlyph(FontStreamReader reader, ushort xMin, ushort yMin, ushort xMax, ushort yMax)
{
var components = new List <CompoundGlyph.Component>();
var flags = GlyphComponentFlags.MoreComponents;
while (flags.HasFlag(GlyphComponentFlags.MoreComponents))
{
flags = (GlyphComponentFlags)reader.ReadUInt16();
var glyphIndex = reader.ReadInt16();
if (flags.HasFlag(GlyphComponentFlags.WeHaveInstructions) && flags.HasFlag(GlyphComponentFlags.MoreComponents))
{
throw new NotImplementedException();
}
var arg1 = flags.HasFlag(GlyphComponentFlags.Arg12AreWords) ? reader.ReadInt16() : reader.ReadUInt8();
var arg2 = flags.HasFlag(GlyphComponentFlags.Arg12AreWords) ? reader.ReadInt16() : reader.ReadUInt8();
var matrix = new decimal[] {
1, 0,
0, 1,
0, 0
};
short?destPointIndex = null;
short?srcPointIndex = null;
if (flags.HasFlag(GlyphComponentFlags.ArgsAreXYValues))
{
matrix[4] = arg1;
matrix[5] = arg2;
}
else
{
destPointIndex = arg1;
srcPointIndex = arg1;
}
if (flags.HasFlag(GlyphComponentFlags.WeHaveAScale))
{
matrix[0] = matrix[3] = reader.ReadF2Dot14();
}
else if (flags.HasFlag(GlyphComponentFlags.WeHaveAnXYScale))
{
matrix[0] = reader.ReadF2Dot14();
matrix[3] = reader.ReadF2Dot14();
}
else if (flags.HasFlag(GlyphComponentFlags.WeHave2By2))
{
matrix[0] = reader.ReadF2Dot14();
matrix[1] = reader.ReadF2Dot14();
matrix[2] = reader.ReadF2Dot14();
matrix[3] = reader.ReadF2Dot14();
}
components.Add(new CompoundGlyph.Component(glyphIndex, matrix, destPointIndex, srcPointIndex));
}
var instructions = new byte[0];
if (flags.HasFlag(GlyphComponentFlags.WeHaveInstructions))
{
var instructionLength = reader.ReadUInt16();
instructions = reader.ReadArray <byte>(instructionLength, r => r.ReadUInt8);
}
return(new CompoundGlyph(components, instructions));
}
private static Glyph ReadSimpleGlyph(FontStreamReader reader, short numberOfContours, ushort xMin, ushort yMin, ushort xMax, ushort yMax)
{
var endPoints = reader.ReadArray <ushort>((ushort)numberOfContours, r => r.ReadUInt16);
var instructionLength = reader.ReadUInt16();
var instructions = reader.ReadArray <byte>(instructionLength, r => r.ReadUInt8);
if (numberOfContours == 0)
{
return(new SimpleGlyph(xMin, yMin, xMax, yMax, endPoints, instructions, new Point[0]));
}
var numberOfPoints = endPoints.Max() + 1;
var flags = new SimpleGlyphFlags[numberOfPoints];
var points = new Point[numberOfPoints];
for (var i = 0; i < numberOfPoints; i++)
{
var flag = (SimpleGlyphFlags)reader.ReadUInt8();
flags[i] = flag;
points[i] = new Point {
OnCurve = flag.HasFlag(SimpleGlyphFlags.OnCurve)
};
if (flag.HasFlag(SimpleGlyphFlags.Repeat))
{
var count = reader.ReadUInt8();
while (count-- > 0)
{
flags[++i] = flag;
points[i] = new Point {
OnCurve = flag.HasFlag(SimpleGlyphFlags.OnCurve)
};
}
}
}
// read X
short value = 0;
for (var i = 0; i < numberOfPoints; i++)
{
var flag = flags[i];
if (flag.HasFlag(SimpleGlyphFlags.XShort))
{
if (flag.HasFlag(SimpleGlyphFlags.XSame))
{
value += reader.ReadUInt8();
}
else
{
value -= reader.ReadUInt8();
}
}
else if (!flag.HasFlag(SimpleGlyphFlags.XSame))
{
value += reader.ReadInt16();
}
points[i].X = value;
}
// read Y
value = 0;
for (var i = 0; i < numberOfPoints; i++)
{
var flag = flags[i];
if (flag.HasFlag(SimpleGlyphFlags.YShort))
{
if (flag.HasFlag(SimpleGlyphFlags.YSame))
{
value += reader.ReadUInt8();
}
else
{
value -= reader.ReadUInt8();
}
}
else if (!flag.HasFlag(SimpleGlyphFlags.YSame))
{
value += reader.ReadInt16();
}
points[i].Y = value;
}
return(new SimpleGlyph(xMin, yMin, xMax, yMax, endPoints, instructions, points));
}
