/// <summary>
/// Creates and reads a TableDirectoryEntry from the font image.
/// </summary>
public static TableDirectoryEntry ReadFrom(OpenTypeFontface fontData)
{
TableDirectoryEntry entry = new TableDirectoryEntry();
entry.Tag = fontData.ReadTag();
entry.CheckSum = fontData.ReadULong();
entry.Offset = fontData.ReadLong();
entry.Length = (int)fontData.ReadULong();
return(entry);
}
public OpenTypeFontTable(OpenTypeFontface fontData, string tag)
{
_fontData = fontData;
if (fontData != null && fontData.TableDictionary.ContainsKey(tag))
{
DirectoryEntry = fontData.TableDictionary[tag];
}
else
{
DirectoryEntry = new TableDirectoryEntry(tag);
}
DirectoryEntry.FontTable = this;
}
/// <summary>
/// Compiles the font to its binary representation.
/// </summary>
void Compile()
{
MemoryStream stream = new MemoryStream();
OpenTypeFontWriter writer = new OpenTypeFontWriter(stream);
int tableCount = TableDictionary.Count;
int selector = _entrySelectors[tableCount];
_offsetTable.Version = 0x00010000;
_offsetTable.TableCount = tableCount;
_offsetTable.SearchRange = (ushort)((1 << selector) * 16);
_offsetTable.EntrySelector = (ushort)selector;
_offsetTable.RangeShift = (ushort)((tableCount - (1 << selector)) * 16);
_offsetTable.Write(writer);
// Sort tables by tag name
string[] tags = new string[tableCount];
TableDictionary.Keys.CopyTo(tags, 0);
Array.Sort(tags, StringComparer.Ordinal);
// Write tables in alphabetical order
int tablePosition = 12 + 16 * tableCount;
for (int idx = 0; idx < tableCount; idx++)
{
TableDirectoryEntry entry = TableDictionary[tags[idx]];
#if DEBUG
if (entry.Tag == "glyf" || entry.Tag == "loca")
{
GetType();
}
#endif
entry.FontTable.PrepareForCompilation();
entry.Offset = tablePosition;
writer.Position = tablePosition;
entry.FontTable.Write(writer);
int endPosition = writer.Position;
tablePosition = endPosition;
writer.Position = 12 + 16 * idx;
entry.Write(writer);
}
writer.Stream.Flush();
int l = (int)writer.Stream.Length;
FontSource = XFontSource.CreateCompiledFont(stream.ToArray());
}
/// <summary>
/// Reads all required tables from the font data.
/// </summary>
internal void Read()
{
// Determine font technology
// ReSharper disable InconsistentNaming
const uint OTTO = 0x4f54544f; // Adobe OpenType CFF data, tag: 'OTTO'
const uint TTCF = 0x74746366; // TrueType Collection tag: 'ttcf'
// ReSharper restore InconsistentNaming
try
{
// Check if data is a TrueType collection font.
uint startTag = ReadULong();
if (startTag == TTCF)
{
_fontTechnology = FontTechnology.TrueTypeCollection;
throw new InvalidOperationException("TrueType collection fonts are not yet supported by PDFsharp.");
}
// Read offset table
_offsetTable.Version = startTag;
_offsetTable.TableCount = ReadUShort();
_offsetTable.SearchRange = ReadUShort();
_offsetTable.EntrySelector = ReadUShort();
_offsetTable.RangeShift = ReadUShort();
// Move to table dictionary at position 12
Debug.Assert(_pos == 12);
//tableDictionary = (offsetTable.TableCount);
if (_offsetTable.Version == OTTO)
{
_fontTechnology = FontTechnology.PostscriptOutlines;
}
else
{
_fontTechnology = FontTechnology.TrueTypeOutlines;
}
for (int idx = 0; idx < _offsetTable.TableCount; idx++)
{
TableDirectoryEntry entry = TableDirectoryEntry.ReadFrom(this);
TableDictionary.Add(entry.Tag, entry);
}
// PDFlib checks this, but it is not part of the OpenType spec anymore
if (TableDictionary.ContainsKey("bhed"))
{
throw new NotSupportedException("Bitmap fonts are not supported by PDFsharp.");
}
// Read required tables
if (Seek(CMapTable.Tag) != -1)
{
cmap = new CMapTable(this);
}
if (Seek(ControlValueTable.Tag) != -1)
{
cvt = new ControlValueTable(this);
}
if (Seek(FontProgram.Tag) != -1)
{
fpgm = new FontProgram(this);
}
if (Seek(MaximumProfileTable.Tag) != -1)
{
maxp = new MaximumProfileTable(this);
}
if (Seek(NameTable.Tag) != -1)
{
name = new NameTable(this);
}
if (Seek(FontHeaderTable.Tag) != -1)
{
head = new FontHeaderTable(this);
}
if (Seek(HorizontalHeaderTable.Tag) != -1)
{
hhea = new HorizontalHeaderTable(this);
}
if (Seek(HorizontalMetricsTable.Tag) != -1)
{
hmtx = new HorizontalMetricsTable(this);
}
if (Seek(OS2Table.Tag) != -1)
{
os2 = new OS2Table(this);
}
if (Seek(PostScriptTable.Tag) != -1)
{
post = new PostScriptTable(this);
}
if (Seek(GlyphDataTable.Tag) != -1)
{
glyf = new GlyphDataTable(this);
}
if (Seek(IndexToLocationTable.Tag) != -1)
{
loca = new IndexToLocationTable(this);
}
if (Seek(GlyphSubstitutionTable.Tag) != -1)
{
gsub = new GlyphSubstitutionTable(this);
}
if (Seek(ControlValueProgram.Tag) != -1)
{
prep = new ControlValueProgram(this);
}
}
catch (Exception)
{
GetType();
throw;
}
}
