Re: [Devel] Enumerating font encoding

[George Williams]

> I don't quite understand the format 2 TrueType charmap -- the code
> seems to index subHeaderKeys using both high and low bytes of the
> character.  Can this really be right?  It seems to restrict the mapping
> pretty severely; 16-bit fonts don't seem able to support any glyphs in
> page 0.
Remember that format 2 is for CJK encodings like SJIS & Wansung where you 
have latin (and katakana) characters encoded in a single byte and Kanji or 
Hangul encoded with double bytes.

As such page 0 is never accessed.

If you have a stream of characters map the first character with the 
subHeaderKey array
        => If the result is 0 then this is a one byte character and you 
use this
                same character to map into the subHeader[0] struct to 
figure out
                the glyph index.
        => If the result is not-0 then this is a two-byte character and 
you use
                the next character to map into subHeader[ch1].

So yes, it does not support a two byte character with a 0 byte in the first 
character. But that case doesn't arise in the CJK maps.