Bug 39418 - libgdiplus does not respect fontconfig fallback
Summary: libgdiplus does not respect fontconfig fallback
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: libgdiplus ()
Version: unspecified
Hardware: All Linux
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2016-03-07 17:01 UTC by Mingye Wang
Modified: 2016-05-06 04:03 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description Mingye Wang 2016-03-07 17:01:57 UTC
In src/font.c:812, GdipCreateFont, fontconfig is used to match the 'best' family from config.

> 812	r = FcPatternGetString (family->pattern, FC_FAMILY, 0, &str);

However, this doesn't seem to be friendly to fallbacks, especially with system-generic names like "Sans". This makes using `new Font ("Sans, size);` in mono give tofus for CJK chars, while directly supplying the CJK font name gives some normal result (well, now the first font).

The output of `fc-match -s "Sans"` is available at https://cfp.vim-cn.com/ccw6. In this case, DejaVuSans was matched first, and then wqy-zenhei, the CJK font.

Cairo seems to provide something like cairo_ft_font_face_create_for_pattern(). Perhaps you can delay the fc interpretation and just store the pattern in `result`...
Comment 1 Mingye Wang 2016-03-07 17:02:34 UTC
This also breaks SystemFonts.DefaultFont in Mono.
Comment 2 Mingye Wang 2016-03-09 17:12:50 UTC
I think I got the point of that cairo thing wrong, and it seems that you need to do that yourselves. Hmm… Should I try the experimental Pango target…
Comment 3 Mingye Wang 2016-05-06 04:03:04 UTC
Woah, it seems that building with pango does solve the problem: https://github.com/AOSC-Dev/aosc-os-abbs/issues/224.

So now preferring basic usability over official support...