About pangowin32...

[Tor Lillqvist <tml iki fi>]

Hi,

Recently somebody complained that Chinese characters don't render in
GTK+ 2.0 (i.e. pangowin32). I had a look at it, and I think the
problem is that pangowin32 only uses a single Win32 font for each
PangoWin32Font. For "sans" it seems to use Arial, and nothing else. My
memory is rather hazy, but I think that it originally (over a year
ago, back when the pangowin32.aliases file was still used) was
supposed to use a list of Win32 fonts for each Pango font, in order to
be able to pick characters from different scripts from different Win32
fonts. (For instance Latin and Hebrew characters from Arial, Chinese
characters from MingLiU, Thai characters from Angsana, etc.)

I think this ability was lost at some time, probably with alexl's
changes over a year ago (2001-08-09: "Also drops the subfont thing,
thereby simplifying the code immensely")

Does anybody have any clearer memory of this, or any idea what would
be the best way to get the multiple-Win32-fonts-per-Pango-font feature
back? I think it is rather essential that CJK character output should
work on Windows in GTK+ 2.0, as it has done for a long time in GTK+
1.3.0 (the gtk-1-3-win32-production branch).

I must admit what little understanding of Pango's internal workings I
had has rusted considerably during the last year or so...  Rather than
hacking on pangowin32 (without really understanding what's going on),
I am tempted to start using the FreeType2 backend on Windows. (Perhaps
as an alternative to pangowin32, selectable at run time with an
environment variable or command-line switch.) This would at least mean
that the work other people have done on pangoft2 would benefit Win32,
too. (For instance there are Arabic and Hebrew shapers for pangoft2)

--tml