[BRLTTY] Footsteps towards better accessibility in Linux

[Aura Kelloniemi]

Hi again,

On 2025-04-09 at 22:11 -0400, Nicolas Pitre <nico at fluxnic.net> wrote:
 > On Fri, 4 Apr 2025, Aura Kelloniemi wrote:
 > > All new double-width and zero-width Unicode code points which have been
 > > introduced since Unicode 5.0. That is where the console driver is at the
 > > moment. I don't know where I could get the list of these code points.
 > > 
 > > Also, Linux console does not support combining characters (which I need), nor
 > > BiDi text (which I don't need, but many do). Proper Unicode rendering (without
 > > alignment issues/terminal garbling) requires supporting tehm.
 > > 
 > > In Unicode a code point and a grapheme cluster are a very different thing, and
 > > there would be a lot to do in order to get proper Unicode support to the
 > > console.
 > > 
 > > If you try to edit files containing a lot of emojis, you will see the
 > > rendering issues. When there are a lot of zero-width characters (like
 > > "variation selectors"), long lines get wrapped, but any Unicode-aware editor
 > > thinks that the content was rendered properly and its rendering logic starts
 > > to work in very bad ways. Combine this with tmux or screen, and there is a
 > > huge mess going on in the terminal.
 > > 
 > > Also, text which uses combining diacritics has the same effect as text with
 > > zero-width characters as programs expect the characters to take less columns
 > > than what they actually do.

 > OK. I think I've fixed all those issues. I stole your description above 
 > for my cover letter and submitted a patch series here:

 >   https://lkml.org/lkml/2025/4/9/1952

This is absolutely great! Thank you!

What does the new implementation do with combining characters? Is it able to
turn a sequence of "combining diaeresis" + "latin small letter a" into ä, or
does it simply discard the combining character?

-- 
Aura