Creating a Tirhuta Keyboard Layout

Post general font related questions (e.g. how to install, convert and use fonts) and requests (looking for fonts, designers etc.) here.
Marcel
Posts: 23
Joined: Mon Sep 28, 2015 3:54 pm

Re: Creating a Tirhuta Keyboard Layout

Postby Marcel » Mon Oct 05, 2015 6:09 am

The unsupported Tirhuta characters are far less when Devanagari Inscript is used for a basis, first because key Z is missing on the Hindi Traditional layout (at least on Windows), as it does not appear in the C source, unlike on Devanagari Inscript. As key Z is not part of any of the three Bengali layouts shipped with Windows neither, this is obviously far from a bug. Hence one reason more to prefer Devanagari Inscript for a basis. It contains almost the same mapping as Hindi Traditional but includes several additional characters. Using Devanagari Inscript as shipped with Windows, only 2 Tirhuta characters are left unmapped and need special processing at layout creation:

11480 TIRHUTA ANJI
114C5 TIRHUTA GVANG

One sees that the major part of my previous post is completely useless, as the solution for mapping Tirhuta script on a keyboard layout for Windows consists in simply take the most complete Hindi layout shipped with Windows, and map Tirhuta correspondingly.

This raises however the question whether Bengali would be an even better choice, as it includes the currency numerators and denominator borrowed from Bengali for use in Tirhuta. But the Tirhuta match shows that Bengali unsupports nine Tirhuta characters instead of only the two as listed above. (The basis is obviously the Bengali layout, because Bengali Inscript and Bengali Inscript Legacy are inferior in keyboard level and character number.) The Bengali layout thus contributes the currency numerals, which Iʼve mapped in the Devanagari grid exactly like they are on Bengali, because the corresponding places were empty.

VEDIC SIGN ARDHAVISARGA has been mapped as projected, in AltGr on the Minus key on which the visarga already is (in Shift), because the minus sign there is already available in the Base shift state. On Hindi Traditional it is doubled in AltGr by the principle of having in the two AltGr shift states the ASCII punctuations following the US-English layout. This rule does not apply on Devanagari Inscript, where several Devanagari characters are mapped in the AltGr shift states, but no ASCII symbols nor punctuations. They are now available when Kana toggle (on CapsLock) is on.

For the mysterious ANJI and GVANG, there are even places left on S and W. But for the sake of Bengali currency numerals, the gvang could be mapped on J, as a stacked double turned dotless j, which from a Maithili point of view is complete nonsense of course. Nevertheless, and in lack of better knowledge, Iʼve mapped them as announced, TIRHUTA ANJI on AltGr + J, TIRHUTA GVANG on AltGr + W.

After that, the only characters left are the North Indic fractions and related symbols:

A830 NORTH INDIC FRACTION ONE QUARTER
A831 NORTH INDIC FRACTION ONE HALF
A832 NORTH INDIC FRACTION THREE QUARTERS
A833 NORTH INDIC FRACTION ONE SIXTEENTH
A834 NORTH INDIC FRACTION ONE EIGHTH
A835 NORTH INDIC FRACTION THREE SIXTEENTHS
A836 NORTH INDIC QUARTER MARK
A837 NORTH INDIC PLACEHOLDER MARK
A838 NORTH INDIC RUPEE MARK
A839 NORTH INDIC QUANTITY MARK

Their relatively little number and list structure allow a traditional mapping without Compose. The first six may be on the [1], [2], and [3] keys in a given shift state for quarters, and in another shift state for sixteenths. Next would come the QUARTER MARK, and the PLACEHOLDER and QUANTITY on the next two keys in the lower shift state. Which shift states exactly, depends on where digits are placed.

I believe that on a keyboard for a script that has digits, and where US-English is readily available as a whole (by pressing CapsLock as a Kana toggle), ASCII digits shouldnʼt be in the forefront. Further, like on Vietnamese keyboard on Windows, there is a strong habit of having digits in AltGr. So I suggest to swap Tirhuta and ASCII digits, so that the former end up in Base, and the latter in AltGr. But of course that can be cancelled after feedback.

That brings up the provisional mapping of North Indic numerals in the Shift and Shift + AltGr shift states on the digit keys, where Hindi Traditional and Devanagari Inscript have both the same six sequences, all of which have the Virama in second (5) or first (1) position, in the Shift shift state of keys [3] through [8]. These sequences cannot be shifted one key towards the right, because the parentheses are in Shift where they are on English layouts. Therefore, the one on key [3] has now been transferred to the uppermost rightmost key next to Backspace, to the right of Plus. The hardware used in India is often based on the Remington key layout, which as far as I understand, has this key removed from the middle row to the benefit of Enter, and placed in the digit row at the expense of Backspace. Hence the third view option in MSKLC.

These sequences (ligatures) are using the following characters:

114C2 TIRHUTA SIGN VIRAMA
1148F TIRHUTA LETTER KA
11496 TIRHUTA LETTER JA
11498 TIRHUTA LETTER NYA
1149E TIRHUTA LETTER TA
114A9 TIRHUTA LETTER RA
114AC TIRHUTA LETTER SHA
114AD TIRHUTA LETTER SSA

And they go as follows (‘\’ stands for the Virama):

Shift + [\] (was:
Shift + 3): \ RA
Shift + 4: RA \
Shift + 5: JA \ NYA
Shift + 6: TA \ RA
Shift + 7: KA \ SSA
Shift + 8: SHA \ RA

I understand that they are facilitating the input, allowing for parts like a mute R, TRA, KSSA, SHRA. Iʼm thankful to William for the introduction to the Virama, which favoured my approach of these ligatures. I must confess that first I overrode them, before correcting the layout the same day but a little later.

I now guess that the more ligatures there are, the faster the input. Much more can be added: In the relevant shift states, 47 key positions are still empty: 7 in Shift, 15 in AltGr, 25 in Shift + AltGr. Filling them up with ligatures brings however a memorization challenge. This is why they should be filled up by default, in case there are users interested in, and everybody may feel free to decide whether to learn where they are, or not. Thatʼs about the most a keyboard driver can do. Beyond is the domain of IMEs.

Beyond, on another plane, is the US-English keyboard layout that is included and is activated by pressing CapsLock, that is KanaLock.(Using SGCaps would have been sufficient for a US-English layout, and can be done if eight levels are needed for Tirhuta. Now some supplemental characters are available in AltGr on digit keys. But SGCaps would have the advantage of seeing the LED, which is not available for KanaLock on Occidental and likewise keyboards. Perhaps there is a way to program this in the driver. The extended numpad is included in turn.

It is essential to avoid switching between keyboard layouts for bilingual input such as HTML markup. Good web pages are best written directly in a text editor using the languages of the web (HTML, CSS, JavaScript, PHP and more), star web developer Rodolphe Rimelé writes in “HTML 5” (2013).

I was willing to implement a Compose tree, but unfortunately Iʼd no time to do this part of the job. I hope it will be done in the future. Iʼd no time left neither to run the tests, which would also have been a waste since no Unicode conformant font available. But I think it will work, as Iʼve checked all relevant parts of the sources, and similarly programmed drivers worked. Iʼm hopeful to recover this some day. Everybody may feel free to modify and recompile, sources are included, the workbook as well, but Iʼd no time to make the diagram, so Iʼve deleted the spreadsheets in this version. My aim is that everybody who does no evil, may come into the benefit of performative keyboard layouts. But I donʼt know the way to ensure this. Feedback is welcome, and I could link to this forum from http://charupdate.info. On this page one can find a fine licence agreement, that everybody is welcome to implement.

The Tirhuta_1 folder is for free download at:
http://bit.ly/1jJ9ais_Tirhuta_1

I hope it will be helpful.

Marcel

Marcel
Posts: 23
Joined: Mon Sep 28, 2015 3:54 pm

Re: Creating a Tirhuta Keyboard Layout

Postby Marcel » Mon Oct 05, 2015 6:12 am

Richard W wrote:
Marcel wrote:Now I guess that TIRHUTA LETTER VOCALIC LL and TIRHUTA LETTER VOCALIC RR might match DEVANAGARI LETTER LLA and DEVANAGARI LETTER RRA,...

No, they match DEVANAGARI LETTER VOCALIC LL and DEVANAGARI LETTER VOCALIC RR.
Effectively these are on Windows Devanagari Inscript, but not on Windows Hindi Traditional which I tried. The match is done, thank you.

Marcel

Marcel
Posts: 23
Joined: Mon Sep 28, 2015 3:54 pm

Re: Creating a Tirhuta Keyboard Layout

Postby Marcel » Mon Oct 05, 2015 6:28 am

William wrote:For each of the characters in the range U+11480..U+114C7, U+114D0..U+114D9 in the font, the glyph is not as in the charts but is simply the last two hexadecimal digits of the code point with a line beneath them so that the pairings are visually distinct.

This would mean that the code point of the intended character is clear when the character is displayed.
That is an excellent idea. This font will allow to test the keyboard layout I just placed on line. This can be achieved running Scanahand Premium on a customized template.

On the keyboard there are all Tirhuta characters extended, as listed in TUS §15.10, plus the ZWJ and ZWNJ, plus the ASCII punctuations that are common on Indic layouts, plus the lasting ASCII characters, plus a set of useful complements as § ° ² ³ ± µ £, plus —, –, and a few more. Plus the characters on the extended numpad, including operator symbols, superscripts, subscripts, arrows. But a good word processor is able to switch between fonts, so that it would be sufficient to have the subset used in Tirhuta extended.

This is not a distraction, as the aim is clearly experimental and helps developing keyboard drivers. It is effectively more useful to have such a font than a true font, because of the lacking knowledge on user side (related to myself).

I'm hopeful that this font is being created, and I look forward to testing and finishing the layout.

For this, layout specific feedback is expected, from everybody and namedly from the applicant.

Best regards,

Marcel

William
Top Typographer
Top Typographer
Posts: 1942
Joined: Tue Sep 14, 2004 6:41 pm
Location: Worcestershire, England
Contact:

Re: Creating a Tirhuta Keyboard Layout

Postby William » Mon Oct 05, 2015 8:43 am

Thank you for your kind comments.

Here is a font.

EX11480A.TTF
(21.71 KiB) Downloaded 30 times


Here is a picture, a Print Screen image made in FontCreator 8.0 and cropped in Microsoft Paint so as to show just the special glyphs.

glyphsEX11480A.png
glyphsEX11480A.png (36.49 KiB) Viewed 3252 times


The font has the special glyphs and also has some basic English characters.

The special glyphs are adapted from glyphs in my Pixel Polka font.

The basic English characters are copied directly from my Quest text font.

There is no copyright notice on the font, though I have put my name in it as follows in the Designer field of the font.

Produced by William Overington to try to help in developing a keyboard for the Tirhuta script.

The new font has the name EX11480A and is in a file EX11480A.TTF

The E is for Experimental, The X could be the second letter of Experimental or could mean Hexadecimal.

The 11480 is the hexadecimal start of the Tirhuta script in Unicode.

The A is because it is version A.

So if people using the font want anything added or altered I will try to do what I can and the next version will be B and so on until the adventure of making a keyboard for Tirhuta is solved.

Naming the file in this way means that the technique could be used for other scripts in the future while keeping file names distinct and meaningful.

William

William
Top Typographer
Top Typographer
Posts: 1942
Joined: Tue Sep 14, 2004 6:41 pm
Location: Worcestershire, England
Contact:

Re: Creating a Tirhuta Keyboard Layout

Postby William » Mon Oct 05, 2015 9:19 am

Here is EX11480B.TTF which adds printing glyphs for ZWNJ and ZWJ.

I had some problems testing this font, possibly because WordPad on this Windows 8.0 computer is presuming zero width rather than the width that I have set.

I had a job using Insert Symbol Other... with Serif PagePlus X7 for ZWNJ and ZWJ but I got the printing glyphs in the end.

Anyway, here is the font.

EX11480B.TTF
(21.91 KiB) Downloaded 31 times


William

Marcel
Posts: 23
Joined: Mon Sep 28, 2015 3:54 pm

Re: Creating a Tirhuta Keyboard Layout

Postby Marcel » Mon Oct 05, 2015 9:40 am

Thank you for this font, I've downloaded it and the image, and hope to find the time of running the tests, which is very time-consuming. As soon as I'd finished the drivers and part of documentation yesterday, I continued the interactive overview of the French layout I'm working on. This diagram needs full font support for display, as it is without images.

I'll post a link in the original thread, in case that Roshan does not follow up the split-off. That is wearisome and should not have been split off. As if what we posted was meant to be useless to him. I didn't mean to waste time on a project that finally is not recieved. However it has brought me a certain experience.
William wrote:The (-a) bit is the virama.

I'm very grateful to William and Richard W for having introduced me to the secrets of Indic languages. It was very helpful for me to know something about the virama when manually converting the ligatures table of Devanagari Inscript / Hindi Traditional, and I remember William's sentence quoted above.

All the best,

Marcel
Last edited by Marcel on Tue Oct 06, 2015 10:44 am, edited 2 times in total.

Marcel
Posts: 23
Joined: Mon Sep 28, 2015 3:54 pm

Re: Creating a Tirhuta Keyboard Layout

Postby Marcel » Mon Oct 05, 2015 10:11 am

William wrote:Here is EX11480B.TTF which adds printing glyphs for ZWNJ and ZWJ.

Thank you, this is very fine, so I can make sure that the keyboard layout inserts these characters. I've been really puzzled to find them in the Shift+Ctrl shift state, as this is normally avoided. However it is but one of the two stated positions Richard W mentioned. I'd set them rather in relation to the space bar, but as there is already a working tradition with keys 1 and 2, that's fine as well. I remember that MSKLC does not allow for other than spacing characters on the space bar, but I didn't test these two; as they are encoded next to the spaces, they might work. However I don't use MSKLC on high level any more except to view keyboard layouts shipped with Windows, and to generate the initial .klc source with the properties and the package.

I'm not quite sure to test today, as I must finish the layout diagram for French. I haven't yet installed the Tirhuta layout neither. It's always wearisome to test, but that's the same for everybody...

Marcel

vnlaodong
Posts: 2
Joined: Fri Dec 04, 2015 10:44 pm
Contact:

Re: Creating a Tirhuta Keyboard Layout

Postby vnlaodong » Sun Dec 06, 2015 12:34 pm

Here is EX11480B.TTF which adds printing glyphs for ZWNJ and ZWJ.

I had some problems testing this font, possibly because WordPad on this Windows 8.0 computer is presuming zero width rather than the width that I have set.

I had a job using Insert Symbol Other... with Serif PagePlus X7 for ZWNJ and ZWJ but I got the printing glyphs in the end. Yes. I think so.
Cung cap giup viec ngay tet uy tin giup viec nha ngay tet gia re giup viec nha chat luong son epoxy 2016


Return to “General Font Discussions”

Who is online

Users browsing this forum: No registered users and 2 guests