[Cjk] CJKutf8 in TeXLive2011 cannot generate copy-and-paste PDF with other CJK fonts

[Nien-Po Chen]

Dear CJK Listers,

A reply from Werner.

Thank you, Werner.

Begin forwarded message:

> From: Werner LEMBERG <wl at gnu.org>
> Date: July 22, 2012 10:42:17 PM GMT+08:00
> To: npchen at saturn.yzu.edu.tw
> Cc: cjk at ffii.org
> Subject: Re: [Cjk] Fwd: CJKutf8 in TeXLive2011 cannot generate copy-and-paste PDF with other CJK fonts
> 
> 
> [Please forward this also to the CJK list.]
> 
>>>> If I attempt to use Type 1 fonts of cw family (available at
>>>> <ftp://cle.linux.org.tw/tex/cjk/fonts/cwt1/>), say 'cwkb', in the
>>>> example above, the resultant PDF looks fine but its copy-and-paste
>>>> text has garbled Chinese text. This is obviously a sympton that
>>>> ToUnicode map is not set properly for this font.
>>> 
>>> Yes.
> 
> After downloading cwk-1.1.tar.gz, I have to correct myself.  It is a
> limitation of pdftex that it doesn't support ToUnicode cmaps for
> virtual fonts.  The CJK package *does* create them, but they aren't
> correctly associated with the base fonts.  In other words, ToUnicode
> cmaps via pdftex work with `cwkc' but not with `cwkb'.
> 
> Note, however, that the cw fonts as distributed are set up perfectly,
> contrary to what I've believed earlier (without actually looking into
> the package).  In particular, correct glyph names from the Adobe Glyph
> List (AGL) are used.  Modern PDF readers like evince don't need
> ToUnicode maps for correct cut-and-paste support!  I've tested your
> example code with `cwkb', and it works just fine in evince.  It's a
> pity that Adobe's Acroread doesn't use its own AGL for Type 1 fonts.
> 
> On the other hand, the recommended way for documents with CJK subfonts
> is latex+dvipdfmx.  Going this route has two advantages:
> 
>  1. The output PDF becomes *much* smaller.  Even for your tiny
>     example, the size shrinks from 45kByte to 14kByte because the
>     Type 1 fonts get converted to CFFs.
> 
>  2. dvipdfmx adds ToUnicode cmaps automatically (this is, not using
>     the special code in my CJK package), even for virtual fonts,
>     making it work with acroread.
> 
> 
>    Werner
>