GNU bug report logs - #19993
25.0.50; Unicode fonts defective on Windows

Previous Next

Full log

Message #59 received at 19993 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: Ilya Zakharevich <ilya <at> math.berkeley.edu>
Cc: 19993 <at> debbugs.gnu.org
Subject: Re: bug#19993: 25.0.50; Unicode fonts defective on Windows
Date: Sun, 08 Mar 2015 17:51:16 +0200

> Date: Sat, 7 Mar 2015 23:41:58 -0800
> From: Ilya Zakharevich <ilya <at> math.berkeley.edu>
> Cc: 19993 <at> debbugs.gnu.org
> 
> The following subrange is “identified”:
> 
>   9       0400 - 04FF          Cyrillic
>           0500 - 052F          Cyrillic Supplement
>           2DE0 - 2DFF          Cyrillic Extended-A
>           A640 - A69F          Cyrillic Extended-B
> 
> What is actually supported:
> 
>   0400 - 04FF    Everything but 04d8,04d9 (Schwa, used in Cyrillic Azeri — but 
> contemporary Azeri is written in Latin) 
>   0500 - 052F    Only 0500 - 0513, 051a - 051d supported
>   2DE0 - 2DFF    None supported (5.1)
>   A640 - A69F    None supported (5.1 and later)

FWIW, on one system I use frequently (a pretty standard Windows 7
machine), the last two blocks are not supported by any font.  Likewise
on another system, an XP with a lot of additional fonts installed.
But if I install GNU Unifont, then Emacs does use it for these blocks.
So somehow we do TRT in some situations.  Maybe these subranges are
just a filter?

> Does it look like a good indication of anything?  I would say no… Do
> you know any other tool looking at this bitmap for choosing which font
> to pick up for a particular character?

I guess by "tool" you mean a technique or algorithm that uses the font
data for selecting the appropriate font?  If so, no, I know very
little in this area, on Windows or elsewhere.  Enumerating all the
glyphs would work, but is probably prohibitively expensive.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.