private byte[] buildHeadTable()
{
using (var bos = new MemoryStream())
using (var output = new BinaryWriter(bos))
{
HeaderTable h = ttf.Header;
WriteFixed(output, h.Version);
WriteFixed(output, h.FontRevision);
WriteUint32(output, 0); // h.CheckSumAdjustment()
WriteUint32(output, h.MagicNumber);
WriteUint16(output, h.Flags);
WriteUint16(output, h.UnitsPerEm);
WriteLongDateTime(output, h.Created);
WriteLongDateTime(output, h.Modified);
WriteSInt16(output, h.XMin);
WriteSInt16(output, h.YMin);
WriteSInt16(output, h.XMax);
WriteSInt16(output, h.YMax);
WriteUint16(output, h.MacStyle);
WriteUint16(output, h.LowestRecPPEM);
WriteSInt16(output, h.FontDirectionHint);
// force long format of 'loca' table
WriteSInt16(output, (short)1); // h.IndexToLocFormat()
WriteSInt16(output, h.GlyphDataFormat);
output.Flush();
return(bos.ToArray());
}
}
private TTFTable ReadTableDirectory(TrueTypeFont font, TTFDataStream raf)
{
TTFTable table;
string tag = raf.ReadString(4);
switch (tag)
{
case CmapTable.TAG:
table = new CmapTable(font);
break;
case GlyphTable.TAG:
table = new GlyphTable(font);
break;
case HeaderTable.TAG:
table = new HeaderTable(font);
break;
case HorizontalHeaderTable.TAG:
table = new HorizontalHeaderTable(font);
break;
case HorizontalMetricsTable.TAG:
table = new HorizontalMetricsTable(font);
break;
case IndexToLocationTable.TAG:
table = new IndexToLocationTable(font);
break;
case MaximumProfileTable.TAG:
table = new MaximumProfileTable(font);
break;
case NamingTable.TAG:
table = new NamingTable(font);
break;
case OS2WindowsMetricsTable.TAG:
table = new OS2WindowsMetricsTable(font);
break;
case PostScriptTable.TAG:
table = new PostScriptTable(font);
break;
case DigitalSignatureTable.TAG:
table = new DigitalSignatureTable(font);
break;
case KerningTable.TAG:
table = new KerningTable(font);
break;
case VerticalHeaderTable.TAG:
table = new VerticalHeaderTable(font);
break;
case VerticalMetricsTable.TAG:
table = new VerticalMetricsTable(font);
break;
case VerticalOriginTable.TAG:
table = new VerticalOriginTable(font);
break;
case GlyphSubstitutionTable.TAG:
table = new GlyphSubstitutionTable(font);
break;
default:
table = ReadTable(font, tag);
break;
}
table.Tag = tag;
table.CheckSum = raf.ReadUnsignedInt();
table.Offset = raf.ReadUnsignedInt();
table.Length = raf.ReadUnsignedInt();
// skip tables with zero length (except glyf)
if (table.Length == 0 && !tag.Equals(GlyphTable.TAG, StringComparison.Ordinal))
{
return(null);
}
return(table);
}
/**
* Parse all tables and check if all needed tables are present.
*
* @param font the TrueTypeFont instance holding the parsed data.
* @ If there is an error parsing the TrueType font.
*/
private void ParseTables(TrueTypeFont font)
{
foreach (TTFTable table in font.Tables)
{
if (!table.Initialized)
{
font.ReadTable(table);
}
}
bool isPostScript = AllowCFF && font.TableMap.ContainsKey(CFFTable.TAG);
HeaderTable head = font.Header;
if (head == null)
{
throw new IOException("head is mandatory");
}
HorizontalHeaderTable hh = font.HorizontalHeader;
if (hh == null)
{
throw new IOException("hhead is mandatory");
}
MaximumProfileTable maxp = font.MaximumProfile;
if (maxp == null)
{
throw new IOException("maxp is mandatory");
}
PostScriptTable post = font.PostScript;
if (post == null && !isEmbedded)
{
// in an embedded font this table is optional
throw new IOException("post is mandatory");
}
if (!isPostScript)
{
IndexToLocationTable loc = font.IndexToLocation;
if (loc == null)
{
throw new IOException("loca is mandatory");
}
if (font.Glyph == null)
{
throw new IOException("glyf is mandatory");
}
}
if (font.Naming == null && !isEmbedded)
{
throw new IOException("name is mandatory");
}
if (font.HorizontalMetrics == null)
{
throw new IOException("hmtx is mandatory");
}
if (!isEmbedded && font.Cmap == null)
{
throw new IOException("cmap is mandatory");
}
}