public static void ReadMaxp(DataReader reader, TableRecord[] tables, ref FaceHeader header)
{
SeekToTable(reader, tables, FourCC.Maxp, required: true);
if (reader.ReadInt32BE() != 0x00010000)
{
throw new InvalidFontException("Font contains an old style maxp table.");
}
header.GlyphCount = reader.ReadUInt16BE();
if (header.GlyphCount > MaxGlyphs)
{
throw new InvalidFontException("Font contains too many glyphs.");
}
// skip maxPoints, maxContours, maxCompositePoints, maxCompositeContours, maxZones
reader.Skip(sizeof(short) * 5);
header.MaxTwilightPoints = reader.ReadUInt16BE();
header.MaxStorageLocations = reader.ReadUInt16BE();
header.MaxFunctionDefs = reader.ReadUInt16BE();
header.MaxInstructionDefs = reader.ReadUInt16BE();
header.MaxStackSize = reader.ReadUInt16BE();
// sanity checking
if (header.MaxTwilightPoints > MaxTwilightPoints || header.MaxStorageLocations > MaxStorageLocations ||
header.MaxFunctionDefs > MaxFunctionDefs || header.MaxInstructionDefs > MaxFunctionDefs ||
header.MaxStackSize > MaxStackSize)
{
throw new InvalidFontException("Font programs have limits that are larger than built-in sanity checks.");
}
}
public unsafe static SbitTable Read(DataReader reader, TableRecord[] tables)
{
if (!SfntTables.SeekToTable(reader, tables, FourCC.Eblc))
return null;
// skip version
var baseOffset = reader.Position;
reader.Skip(sizeof(int));
// load each strike table
var count = reader.ReadInt32BE();
if (count > MaxBitmapStrikes)
throw new InvalidFontException("Too many bitmap strikes in font.");
var sizeTableHeaders = stackalloc BitmapSizeTable[count];
for (int i = 0; i < count; i++)
{
sizeTableHeaders[i].SubTableOffset = reader.ReadUInt32BE();
sizeTableHeaders[i].SubTableSize = reader.ReadUInt32BE();
sizeTableHeaders[i].SubTableCount = reader.ReadUInt32BE();
// skip colorRef, metrics entries, start and end glyph indices
reader.Skip(sizeof(uint) + sizeof(ushort) * 2 + 12 * 2);
sizeTableHeaders[i].PpemX = reader.ReadByte();
sizeTableHeaders[i].PpemY = reader.ReadByte();
sizeTableHeaders[i].BitDepth = reader.ReadByte();
sizeTableHeaders[i].Flags = (BitmapSizeFlags)reader.ReadByte();
}
// read index subtables
var indexSubTables = stackalloc IndexSubTable[count];
for (int i = 0; i < count; i++)
{
reader.Seek(baseOffset + sizeTableHeaders[i].SubTableOffset);
indexSubTables[i] = new IndexSubTable
{
FirstGlyph = reader.ReadUInt16BE(),
LastGlyph = reader.ReadUInt16BE(),
Offset = reader.ReadUInt32BE()
};
}
// read the actual data for each strike table
for (int i = 0; i < count; i++)
{
// read the subtable header
reader.Seek(baseOffset + sizeTableHeaders[i].SubTableOffset + indexSubTables[i].Offset);
var indexFormat = reader.ReadUInt16BE();
var imageFormat = reader.ReadUInt16BE();
var imageDataOffset = reader.ReadUInt32BE();
}
return null;
}
public unsafe static SbitTable Read(DataReader reader, TableRecord[] tables)
{
if (!SfntTables.SeekToTable(reader, tables, FourCC.Eblc))
{
return(null);
}
// skip version
var baseOffset = reader.Position;
reader.Skip(sizeof(int));
// load each strike table
var count = reader.ReadInt32BE();
if (count > MaxBitmapStrikes)
{
throw new Exception("Too many bitmap strikes in font.");
}
var sizeTableHeaders = stackalloc BitmapSizeTable[count];
for (int i = 0; i < count; i++)
{
sizeTableHeaders[i].SubTableOffset = reader.ReadUInt32BE();
sizeTableHeaders[i].SubTableSize = reader.ReadUInt32BE();
sizeTableHeaders[i].SubTableCount = reader.ReadUInt32BE();
// skip colorRef, metrics entries, start and end glyph indices
reader.Skip(sizeof(uint) + sizeof(ushort) * 2 + 12 * 2);
sizeTableHeaders[i].PpemX = reader.ReadByte();
sizeTableHeaders[i].PpemY = reader.ReadByte();
sizeTableHeaders[i].BitDepth = reader.ReadByte();
sizeTableHeaders[i].Flags = (BitmapSizeFlags)reader.ReadByte();
}
// read index subtables
var indexSubTables = stackalloc IndexSubTable[count];
for (int i = 0; i < count; i++)
{
reader.Seek(baseOffset + sizeTableHeaders[i].SubTableOffset);
indexSubTables[i] = new IndexSubTable
{
FirstGlyph = reader.ReadUInt16BE(),
LastGlyph = reader.ReadUInt16BE(),
Offset = reader.ReadUInt32BE()
};
}
// read the actual data for each strike table
for (int i = 0; i < count; i++)
{
// read the subtable header
reader.Seek(baseOffset + sizeTableHeaders[i].SubTableOffset + indexSubTables[i].Offset);
var indexFormat = reader.ReadUInt16BE();
var imageFormat = reader.ReadUInt16BE();
var imageDataOffset = reader.ReadUInt32BE();
}
return(null);
}
public static void ReadMaxp(DataReader reader, TableRecord[] tables, ref FaceHeader header)
{
SeekToTable(reader, tables, FourCC.Maxp, required: true);
if (reader.ReadInt32BE() != 0x00010000)
throw new InvalidFontException("Font contains an old style maxp table.");
header.GlyphCount = reader.ReadUInt16BE();
if (header.GlyphCount > MaxGlyphs)
throw new InvalidFontException("Font contains too many glyphs.");
// skip maxPoints, maxContours, maxCompositePoints, maxCompositeContours, maxZones
reader.Skip(sizeof(short) * 5);
header.MaxTwilightPoints = reader.ReadUInt16BE();
header.MaxStorageLocations = reader.ReadUInt16BE();
header.MaxFunctionDefs = reader.ReadUInt16BE();
header.MaxInstructionDefs = reader.ReadUInt16BE();
header.MaxStackSize = reader.ReadUInt16BE();
// sanity checking
if (header.MaxTwilightPoints > MaxTwilightPoints || header.MaxStorageLocations > MaxStorageLocations ||
header.MaxFunctionDefs > MaxFunctionDefs || header.MaxInstructionDefs > MaxFunctionDefs ||
header.MaxStackSize > MaxStackSize)
throw new InvalidFontException("Font programs have limits that are larger than built-in sanity checks.");
}
