Rick McGowan (firstname.lastname@example.org) wrote:
>I think the "Unicode CMAP" is convenient for some things to some people.
>Rendering of Unicode text for display is a complex problem. To do it, you
>need one or more ordered sets of glyphs, and a means of translating from
>stream of character codes into a corresponding stream of glyph codes. Just
>having a "Unicode CMAP" doesn't get you the second piece. It will get you
>long way in the Latin script and in CJK, but it won't get you much past
>into the more complex scripts.
In Apple's model, the cmap is not the only piece of the
character-to-glyph mapping. Character-to-glyph mapping is done through
the combination of the 'cmap' table and the 'mort' table. There are two
tables rather than one for historical reasons; the 'sfnt' font format was
originally defined without thought being given to complex scripts. But
Rick is correct in that a 'cmap' table alone is insufficient to correctly
map all Unicode characters to glyphs.
International and Text Department Architect
Apple Computer, Inc.
This archive was generated by hypermail 2.1.2 : Tue Jul 10 2001 - 17:20:40 EDT