private static TrueTypeFont ParseTables(decimal version, IReadOnlyDictionary <string, TrueTypeHeaderTable> tables, TrueTypeDataBytes data)
{
var isPostScript = tables.ContainsKey(TrueTypeHeaderTable.Cff);
var tableRegister = new TableRegister();
if (!tables.TryGetValue(TrueTypeHeaderTable.Head, out var table))
{
throw new InvalidOperationException($"The {TrueTypeHeaderTable.Head} table is required.");
}
// head
tableRegister.HeaderTable = HeaderTable.Load(data, table);
if (!tables.TryGetValue(TrueTypeHeaderTable.Hhea, out var hHead))
{
throw new InvalidOperationException("The horizontal header table is required.");
}
// hhea
tableRegister.HorizontalHeaderTable = HorizontalHeaderTable.Load(data, hHead);
if (!tables.TryGetValue(TrueTypeHeaderTable.Maxp, out var maxHeaderTable))
{
throw new InvalidOperationException("The maximum profile table is required.");
}
// maxp
tableRegister.MaximumProfileTable = BasicMaximumProfileTable.Load(data, maxHeaderTable);
// post
if (tables.TryGetValue(TrueTypeHeaderTable.Post, out var postscriptHeaderTable))
{
tableRegister.PostScriptTable = PostScriptTable.Load(data, table, tableRegister.MaximumProfileTable);
}
if (!isPostScript)
{
if (!tables.TryGetValue(TrueTypeHeaderTable.Loca, out var indexToLocationHeaderTable))
{
throw new InvalidOperationException("The location to index table is required for non-PostScript fonts.");
}
// loca
tableRegister.IndexToLocationTable =
IndexToLocationTable.Load(data, indexToLocationHeaderTable, tableRegister);
if (!tables.TryGetValue(TrueTypeHeaderTable.Glyf, out var glyphHeaderTable))
{
throw new InvalidOperationException("The glpyh table is required for non-PostScript fonts.");
}
// glyf
tableRegister.GlyphDataTable = GlyphDataTable.Load(data, glyphHeaderTable, tableRegister);
OptionallyParseTables(tables, data, tableRegister);
}
return(new TrueTypeFont(version, tables, tableRegister));
}
private static void OptionallyParseTables(IReadOnlyDictionary <string, TrueTypeHeaderTable> tables, TrueTypeDataBytes data, TableRegister tableRegister)
{
// cmap
if (tables.TryGetValue(TrueTypeHeaderTable.Cmap, out var cmap))
{
tableRegister.CMapTable = CMapTable.Load(data, cmap, tableRegister);
}
// hmtx
if (tables.TryGetValue(TrueTypeHeaderTable.Hmtx, out var hmtxHeaderTable))
{
tableRegister.HorizontalMetricsTable = HorizontalMetricsTable.Load(data, hmtxHeaderTable, tableRegister);
}
// name
if (tables.TryGetValue(TrueTypeHeaderTable.Name, out var nameHeaderTable))
{
// TODO: Not important
}
// os2
// kern
}