[BRLTTY] What is the best way to deal with Unicode characters?

[Aura Kelloniemi]

Hello,

Shérab <Sebastien.Hinderer at ens-lyon.org> writes:
 > Several researchers I work with tend to use Unicode characters to
 > include mathematical symbols in their texts. For instance, they use greek
 > letters and logical symbols such as arrows, quantifiers, conjunctions and
 > disjunctions, etc. This tendency is encouraged by the fact that
 > some proof assistants such as Agda themselves support these characters
 > and encourage their use.
[--]
 > I am wondering whether you guys have opinions or suggestions about how
 > to best deal with this problem.

In my opinion the best that can be done now is to use a custom contraction
table to get multi-cell characters. It is complicated to set up, but should
work. (It is so complicated, that I haven't had time to do it, so I'm just
suffering and using the DESCCHAR function).

I wish that BRLTTY would more easily support multi-cell characters. Many
scripts supported by Unicode contain glyphs that are wider than just one
regular terminal cell, so multi-cell is coming nevertheless. Unfortunately
glyphs that are both visually and braillewise wide will probably not be the
basic case, but rather an exception. This leads to the problems associated
with multi-cell characters which you pointed to.

One solution that would help with this issue would be to allow blinking dots.
Even now brltty has the 'Blinking Capitals' option. This feature could be
extended to allow the user to define specific dots that will be blinking in a
character.

For example the arrow right could be defined like the letter O (dots 1, 3 and
5) with the dot 7 blinking.

 > Should we ask people to refrain from
 > using such characters,

No, in my opinion, because Unicode is the best solution introduced so far to
extend the facilities of ASCII. If people don't use Unicode, they use
something much less portable e.g. custom fonts or even images.

-- 
Aura