/**
* <summary>Loads general tables.</summary>
*/
private void LoadTables()
{
// Font Header ('head' table).
int tableOffset;
if (!tableOffsets.TryGetValue("head", out tableOffset))
{
throw new ParseException("'head' table does NOT exist.");
}
// Go to the font flags!
FontData.Seek(tableOffset + 16);
Metrics.Flags = FontData.ReadUnsignedShort();
Metrics.UnitsPerEm = FontData.ReadUnsignedShort();
Metrics.UnitNorm = 1000f / Metrics.UnitsPerEm;
// Go to the bounding box limits!
FontData.Skip(16);
Metrics.XMin = FontData.ReadShort();
Metrics.YMin = FontData.ReadShort();
Metrics.XMax = FontData.ReadShort();
Metrics.YMax = FontData.ReadShort();
Metrics.MacStyle = FontData.ReadUnsignedShort();
// Font Header ('OS/2' table).
if (tableOffsets.TryGetValue("OS/2", out tableOffset))
{
FontData.Seek(tableOffset);
int version = FontData.ReadUnsignedShort();
// Go to the ascender!
FontData.Skip(66);
Metrics.STypoAscender = FontData.ReadShort();
Metrics.STypoDescender = FontData.ReadShort();
Metrics.STypoLineGap = FontData.ReadShort();
if (version >= 2)
{
FontData.Skip(12);
Metrics.SxHeight = FontData.ReadShort();
Metrics.SCapHeight = FontData.ReadShort();
}
else
{
/*
* NOTE: These are just rule-of-thumb values,
* in case the xHeight and CapHeight fields aren't available.
*/
Metrics.SxHeight = (short)(.5 * Metrics.UnitsPerEm);
Metrics.SCapHeight = (short)(.7 * Metrics.UnitsPerEm);
}
}
// Horizontal Header ('hhea' table).
if (!tableOffsets.TryGetValue("hhea", out tableOffset))
{
throw new ParseException("'hhea' table does NOT exist.");
}
// Go to the ascender!
FontData.Seek(tableOffset + 4);
Metrics.Ascender = FontData.ReadShort();
Metrics.Descender = FontData.ReadShort();
Metrics.LineGap = FontData.ReadShort();
Metrics.AdvanceWidthMax = FontData.ReadUnsignedShort();
Metrics.MinLeftSideBearing = FontData.ReadShort();
Metrics.MinRightSideBearing = FontData.ReadShort();
Metrics.XMaxExtent = FontData.ReadShort();
Metrics.CaretSlopeRise = FontData.ReadShort();
Metrics.CaretSlopeRun = FontData.ReadShort();
// Go to the horizontal metrics count!
FontData.Skip(12);
Metrics.NumberOfHMetrics = FontData.ReadUnsignedShort();
// PostScript ('post' table).
if (!tableOffsets.TryGetValue("post", out tableOffset))
{
throw new ParseException("'post' table does NOT exist.");
}
// Go to the italic angle!
FontData.Seek(tableOffset + 4);
Metrics.ItalicAngle = FontData.ReadFixed32();
Metrics.UnderlinePosition = FontData.ReadShort();
Metrics.UnderlineThickness = FontData.ReadShort();
Metrics.IsFixedPitch = (FontData.ReadInt() != 0);
}