[XeTeX] CID-keyed font support?

[Jiang Jiang]

Hi,

On Sat, Jul 19, 2014 at 3:12 PM, Akira Kakuto <kakuto at fuk.kindai.ac.jp> wrote:
> Dear Jiang Jiang ,
>
>
>> I will take a look at the warnings for non-CJK fonts.
>
>
> Thanks.
> In addition, I think it is necessary to refine for dvipdfmx.
> The patched sources do not compile as "dvipdfmx".

Right, I can look into that.

> My friend says that the present dvipdfmx can handle
> Source Han Sans JP by translating the CMap
> UniSourceHanSansJP-UTF32-H  into UniSourceHanSansJP-UTF16-H.

Yes, if you look at the logic there, it was trying to resolve the
ToUnicode CMap by first attempting to load SourceHanSansJP-UTF16-H in
texmf tree (with kpathsea), if this couldn't be found it will try
SourceHanSansJP-UCS2-H instead, if that couldn't be found it will have
to bail out. What I changed there is adding yet another fallback to
use reverse SFNT CMap lookup (otf_create_ToUnicode_stream) to find the
matching Unicode code points for used glyphs.

It will certainly be better if SourceHanSansJP-UTF16-H can be found,
or UniSourceHanSansJP-UTF32-H can be loaded by dvipdfm-x directly (it
should support that anyway). But I just think this font should work
out of the box, without requiring external mapping files to be
present. I suppose we can't find such SourceHanSansJP-UTF16-H file
embedded in the font itself? Then fallback to the brute force method
(otf_create_ToUnicode_stream) is the only way I can think of. Of
course I'm not familiar with CID-keyed fonts at all so I can be wrong.

I'm always curious what would be the better way to gather such
information, do you think I should just ask Dr. Ken Lunde about it?

- Jiang