public ushort LookupIndex(int codepoint, int nextCodepoint = 0)
{
// https://www.microsoft.com/typography/OTSPEC/cmap.htm
// "character codes that do not correspond to any glyph in the font should be mapped to glyph index 0."
ushort ret = 0;
if (!_codepointToGlyphs.TryGetValue(codepoint, out ret))
{
foreach (CharacterMap cmap in _charMaps)
{
ushort gid = cmap.CharacterToGlyphIndex(codepoint);
//https://www.microsoft.com/typography/OTSPEC/cmap.htm
//...When building a Unicode font for Windows, the platform ID should be 3 and the encoding ID should be 1
if (ret == 0 || (gid != 0 && cmap.PlatformId == 3 && cmap.EncodingId == 1))
{
ret = gid;
}
}
_codepointToGlyphs[codepoint] = ret;
}
// If there is a second codepoint, we are asked whether this is an UVS sequence
// -> if true, return a glyph ID
// -> otherwise, return 0
if (nextCodepoint > 0)
{
foreach (CharacterMap cmap in _charMaps)
{
if (cmap is CharMapFormat14)
{
CharMapFormat14 cmap14 = cmap as CharMapFormat14;
ushort gid = cmap14.CharacterPairToGlyphIndex(codepoint, ret, nextCodepoint);
if (gid > 0)
{
return(gid);
}
}
}
return(0);
}
return(ret);
}
private static CharacterMap ReadCharacterMap(BinaryReader input)
{
ushort format = input.ReadUInt16();
switch (format)
{
default:
Utils.WarnUnimplemented("cmap subtable format {0}", format);
return(new NullCharMap());
case 0: return(ReadFormat_0(input));
case 2: return(ReadFormat_2(input));
case 4: return(ReadFormat_4(input));
case 6: return(ReadFormat_6(input));
case 12: return(ReadFormat_12(input));
case 14: return(CharMapFormat14.Create(input));
}
}
