[XeTeX] XeTeX/xdvipdfmx: PDF text copying with double encoded fonts

[Akira Kakuto]

Dear Jiang,

> There has been a report
>
> https://github.com/CTeX-org/ctex-kit/issues/286

% XeTeX
\XeTeXgenerateactualtext=1
\font\1="Source Han Sans SC"
\font\2="Source Han Serif SC"
\font\3="Microsoft YaHei"

{\1 孤立子 ABC} \par
{\2 孤立子 ABC} \par
{\3 孤立子 ABC} \par

\bye

I tested the above example on Windows 7.
Used fonts are
(1) SourceHanSansSC-Regular.otf
(2) SourceHanSerifSC-Regular.otf
(3) msyh.ttf

I'm afraid that I don't understand the problem correctly.
My Results:

In the case of \XeTeXgenerateactualtext=0, copy&paste
is wrong for "立" in fonts (1) and (2), in Adobe Reader DC.
In the case of \XeTeXgenerateactualtext=1, copy&pase
is OK in Adobe Reader DC for all fonts (1), (2) and (3).

Best,
Akira