/// <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;
}
}
/// <summary>
/// Adds the specified table to this font image.
/// </summary>
public void AddTable(OpenTypeFontTable fontTable)
{
if (!CanWrite)
{
throw new InvalidOperationException("Font image cannot be modified.");
}
if (fontTable == null)
{
throw new ArgumentNullException("fontTable");
}
if (fontTable._fontData == null)
{
fontTable._fontData = this;
}
else
{
Debug.Assert(fontTable._fontData.CanRead);
// Create a reference to this font table
fontTable = new IRefFontTable(this, fontTable);
}
//Debug.Assert(fontTable.FontData == null);
//fontTable.fontData = this;
TableDictionary[fontTable.DirectoryEntry.Tag] = fontTable.DirectoryEntry;
switch (fontTable.DirectoryEntry.Tag)
{
case TableTagNames.CMap:
cmap = fontTable as CMapTable;
break;
case TableTagNames.Cvt:
cvt = fontTable as ControlValueTable;
break;
case TableTagNames.Fpgm:
fpgm = fontTable as FontProgram;
break;
case TableTagNames.MaxP:
maxp = fontTable as MaximumProfileTable;
break;
case TableTagNames.Name:
name = fontTable as NameTable;
break;
case TableTagNames.Head:
head = fontTable as FontHeaderTable;
break;
case TableTagNames.HHea:
hhea = fontTable as HorizontalHeaderTable;
break;
case TableTagNames.HMtx:
hmtx = fontTable as HorizontalMetricsTable;
break;
case TableTagNames.OS2:
os2 = fontTable as OS2Table;
break;
case TableTagNames.Post:
post = fontTable as PostScriptTable;
break;
case TableTagNames.Glyf:
glyf = fontTable as GlyphDataTable;
break;
case TableTagNames.Loca:
loca = fontTable as IndexToLocationTable;
break;
case TableTagNames.GSUB:
gsub = fontTable as GlyphSubstitutionTable;
break;
case TableTagNames.Prep:
prep = fontTable as ControlValueProgram;
break;
}
}