Re: Request to add a new layout for Malayalam

[Mike FABIAN]

Ajith R <ajithramayyan@yahoo.co.in> さんはかきました:

> Dear Mike,
>
>> Great, thank you! I’ll try to make a new m17n-db release next week with
>> your new input method.
>
> That will be great! Thanks.
>
> QWERTY the common system layout, for example, has a set of characters you get 
> by pressing the keys by itself and another by pressing shift/caps.
>
> Malayalam has more than 100 unicode points. In the layout I submitted,
> uncommonly used characters are not included. I was not sure how to
> include them in my layout when the system layout has only the
> "unshifted" and "shifted" plains / layers. 
>
> If the system layout has more than two such sets - one set of
> 'unshifted' characters, another set of 'shifted' characters and an
> additional set of characters you get by pressing a third level
> modifier (say the window key), can ibus transform the characters you
> get when you press the third level modifier? Say, I have a modified
> system layout which returns, say Greek characters when I press the
> third level modifiers. Can I have ibus translate them to the malayalam
> archaic characters ( which are not included currently)? This was what
> I had in mind when I asked about support for more than two levels.
>
> Though I don't understand the
> example 
> https://git.savannah.nongnu.org/cgit/m17n/m17n-db.git/tree/MIM/bn-national-jatiya.mim
> completely, I think it implements most of the features I want in my
> pnC. A few doubts -
>
> 1) In expressions like ((G-i) "ঽ") ; U+09BD BENGALI SIGN AVAGRAHA, what does 
> G-i without the quotes represent?

The G- represents pressing the ISO_Level3_Shift key which is usually the
right Alt key (often also called the AltGr key). If you look at the
keyboard layout pictures in

https://en.wikipedia.org/wiki/List_of_QWERTY_keyboard_language_variants

you see that many of the QWERTY layouts have "Alt Gr" written on top of
the right Alt key. An exception is the US keyboard layout, which has a
second Alt key instead:

Wikipedia> The US keyboard layout has a second Alt key instead of the
Wikipedia> AltGr key and does not use any dead keys; this makes it
Wikipedia> inefficient for all but a handful of languages.

So don’t use the US keyboard layout if you want something like

((G-i) "ঽ")

to work, you can use the "English (India, with rupee)" keyboard layout
instead for example. It is basically a variant of the US layout changing
the right Alt key to ISO_Level3_Shift and adding a rupee sign on
AltGr+4:

$ grep -B2 -A 10 'xkb_symbols "eng"' /usr/share/X11/xkb/symbols/in

partial alphanumeric_keys
xkb_symbols "eng" {

    include "us(basic)"
    name[Group1]= "English (India, with rupee)";

    include "rupeesign(4)"
    include "level3(ralt_switch)"
};

$ grep -B4 -A3 'xkb_symbols "ralt_switch"' /usr/share/X11/xkb/symbols/level3 

// The default behaviour:
// the right Alt key (AltGr) chooses the third symbol engraved on a key.
default partial modifier_keys
xkb_symbols "ralt_switch" {
  key <RALT> {[  ISO_Level3_Shift  ], type[group1]="ONE_LEVEL" };
};

$ cat /usr/share/X11/xkb/symbols/rupeesign 
// keyboards having the RupeeSign on the 4 key
partial
xkb_symbols "4" {
    key <AE04>  { [  NoSymbol,   NoSymbol,   U20B9 ]    };
};

As long as you use a keyboard layout which has ISO_Level3_Shift
somewhere, you can use the "G-" in m17n-db.

In Gnome you can select it like this (similar in other desktops):

Screenshot-keyboard-with-iso-level3-shift.png
Description: PNG image

> 2) Can you please point me to the documentation of features ‌/commands like 
> variable, set, cond etc

Some documentation is here:

https://www.nongnu.org/m17n/documentation.html

especially this page:

https://www.nongnu.org/m17n/manual-en/m17nDBTutorial.html

and I also found it helpful to look at the other .mim files which
already exist in m17n-db as examples.


-- 
Mike FABIAN <mfabian@redhat.com>
睡眠不足はいい仕事の敵だ。