private TrueTypeFontTable ReadHorizontalMetrics(uint length, TrueTypeTableEntryList list, BigEndianReader reader)
{
var pos = reader.Position;
//Get the number of entries for the hMetrics list from the horizontal header table.
TrueTypeTableEntry hhead = list["hhea"];
if (hhead == null)
{
throw new ArgumentNullException("No horizontal header (hhea) has been specified in the font file, this is needed to load the hroizontal metrics");
}
if (hhead.Table == null)
{
TrueTypeFontTable tbl = this.ReadTable(hhead, list, reader);
if (tbl == null)
{
throw new ArgumentNullException("No horizontal header (hhea) has been specified in the font file, this is needed to load the hroizontal metrics");
}
hhead.SetTable(tbl);
}
TrueTypeTableEntry os2 = list["OS/2"];
if (os2 == null)
{
throw new ArgumentNullException("No OS2 table has been specified in the font file, this is a required table and needed to load the horizontal metrics");
}
if (os2.Table == null)
{
TrueTypeFontTable tbl = this.ReadTable(os2, list, reader);
if (tbl == null)
{
throw new ArgumentNullException("No OS/2 has been specified in the font file, this is needed to load the hroizontal metrics");
}
os2.SetTable(tbl);
}
if (reader.Position != pos)
{
reader.Position = pos;
}
int firstcharindex = (os2.Table as OS2Table).FirstCharIndex;
HorizontalMetrics hm = new HorizontalMetrics(reader.Position);
ushort count = (hhead.Table as SubTables.HorizontalHeader).NumberOfHMetrics;
List <HMetric> metrics = new List <HMetric>();
for (int i = 0; i < count; i++)
{
SubTables.HMetric metric = new HMetric(reader.ReadUInt16(), reader.ReadInt16(), (char)(i + firstcharindex));
metrics.Add(metric);
}
hm.HMetrics = metrics;
return(hm);
}
protected void Read(BigEndianReader reader)
{
TrueTypeHeader header;
if (TrueTypeHeader.TryReadHeader(reader, out header) == false)
{
throw new NotSupportedException("The current stream is not a supported OpenType or TrueType font file");
}
List <TrueTypeTableEntry> dirs;
try
{
dirs = new List <TrueTypeTableEntry>();
for (int i = 0; i < header.NumberOfTables; i++)
{
TrueTypeTableEntry dir = new TrueTypeTableEntry();
dir.Read(reader);
dirs.Add(dir);
}
dirs.Sort(delegate(TrueTypeTableEntry one, TrueTypeTableEntry two) { return(one.Offset.CompareTo(two.Offset)); });
this._dirs = new TrueTypeTableEntryList(dirs);
this._head = header;
TrueTypeTableFactory factory = this.GetFactory(header);
foreach (TrueTypeTableEntry dir in dirs)
{
TrueTypeFontTable tbl = factory.ReadTable(dir, this, reader);
if (tbl != null)
{
dir.SetTable(tbl);
}
}
}
catch (Exception ex) { throw new TypefaceReadException("Could not read the TTF File", ex); }
}