GSOC New idea - Braille extension for XKB

[Samuel Thibault]

Hello,

Nalin.x.Linux, le Sun 02 Mar 2014 23:01:27 +0530, a écrit :
> I would like to make braille extension for XKB(X keyboard extension).

Interesting!

> Let me know if any work in this regard has been undertaken by xorg and if so
> let me know the existing position thanking you.

There is already some basic implementation available, see the "brai"
keyboard layout and its variants.  What it does is the PC keyboard
driver part. For instance, I use xkb layout "fr,brai", and variant
"oss,", and the grp:shift_caps_toggle xkb option.  By pressing
shift+capslock, I can switch between my usual french layout and the
braille layout.  When in braille layout, the sdfjkl keys act as a
braille keyboard, and produce Unicode braille patterns (U+28XY). Some
variants are provided for left-handed/right-handed, keypad, etc. but the
base variant should be already fine for most users.

After that, not much is implemented, and a GSOC project would be welcome
indeed.  For the moment, all I did was to add to brltty-ttb the ability
to create a .XCompose file, which typically contains

<braille_dots_1> : "a"
<braille_dots_12> : "b"
<braille_dots_14> : "c"

etc., thus automatically turning the Unicode braille patterns to text
according to brltty TTB table used to create the .XCompose file.  This
just works as expected for grade-1. For grade-2, one could use the same
principle, but I don't think the trickyness of braille contraction can
be expressed with compose.

As a consequence, what I believe would be useful to implement in your
project would be an input method module, which would take the unicode
braille patterns as input, and use liblouis to turn that into text.  I
don't know which kind of module is most preferred nowadays (SCIM? UIM?)
but I guess Xorg people can answer that :)

You'll probably want to look for documentation for what an input module
is, but basically it is a piece of code which gets in the way of typing
text in Xorg, e.g. to type kanjis and things like that which are not
mere XKB 1-to-1 translations.

At any rate, I'd happily mentor such a project!

Samuel