Creating a Tirhuta Keyboard Layout

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Marcel
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Re: Creating a Tirhuta Keyboard Layout

Postby Marcel » Fri Oct 02, 2015 11:17 am

William wrote:When it comes to making the Unicode font, one could use Scanahand to get something to get started.

I'm afraid Scanahand does not allow to map SMP characters, does it? In any case, there are one hundred dollars off on Font Creator Professional until the day after tomorrow, fifty dollars on Standard edition:
http://www.high-logic.com/shop/new-licenses.html

William
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Re: Creating a Tirhuta Keyboard Layout

Postby William » Fri Oct 02, 2015 11:41 am

Marcel wrote:That's right. And as my mother tongue is German, I understand even better that by talking of a "demand," I actually could have meant what in German is a Forderung instead of an Anfrage.


My knowledge of French is only basic and my knowledge of German is less.

I have written song lyrics in French and song lyrics in Esperanto. I have not yet tried to write song lyrics in German.

Yet that is two more words to add to my knowledge.

I like German volksmusik. We used to get it on the Astra satellite system in the 1990s. I still get some of it on YouTube.

I tend to use Google translate to translate titles and lyrics when I can find lyrics. Thus gradually my knowledge increases.

Sometimes I understand parts of it, it is as if it is like magic, I am listening to the music and not understanding the words and then suddenly I do understand the words and then it goes again!

Marcel wrote:But please permit me to note that I did not use the verb, I did not write: "That resolves half of the support Roshan demanded," but only: "that resolves almost one half or even more of Roshan's demand." In English, as well as in French (and in German), a demand (or demande, Nachfrage is also the economical fact of a good being asked for:
1.2 [mass noun] The desire of consumers, clients, employers, etc. for a particular commodity, service, or other item:
a recent slump in demand
[count noun]: a demand for specialists
http://www.oxforddictionaries.com/definition/english/demand
And I hurry up thanking you for the many links you provided to dictionaries, among which the above, and to the Unicode Mailing List exchange which illustrates very well the difference between "requests or suggestions" and "demands".


Well, I understand what you mean, but in my own experience, which is not everything by a long way, the word demand used as a noun in the manner you mention is used in a generalized plural sense.

Marcel wrote:Font for Tirhuta script


I like the art with the lettering. I had not realized that that was possible in this forum.

Marcel wrote:Unfortunately there is even more than one word wrong in my last post, as the linked font is not Unicode conformant, it only maps ASCII to Tirhuta, like the legacy fonts that ship with WordPerfect for backwards compatibility, and despite of being maintained, it does not seem to have been updated since Tirhuta has been encoded in Unicode. The citations of the UCD and more lead me to the assumption that the font is up do date. We will have to make a request for a Unicode version of this font, which would be easy to perform as the glyph problem is actually resolved, at least to a certain extent (given the complexity of the script, which posts I'll answer next).


The link to the font is very useful as there is a link to contact the lady who contributed the font.

So maybe permission, or even help, will be forthcoming so that the converting of a copy of that font to a Unicode font might become possible.

William

The edit is to correct a spelling mistake.
Last edited by William on Fri Oct 02, 2015 1:10 pm, edited 1 time in total.

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Re: Creating a Tirhuta Keyboard Layout

Postby William » Fri Oct 02, 2015 12:05 pm

Marcel wrote:
William wrote:When it comes to making the Unicode font, one could use Scanahand to get something to get started.

I'm afraid Scanahand does not allow to map SMP characters, does it?


I have the Premium version and that does.

Marcel wrote:In any case, there are one hundred dollars off on Font Creator Professional until the day after tomorrow, fifty dollars on Standard edition:
http://www.high-logic.com/shop/new-licenses.html


Ah, I was thinking in terms of, if it is allowed in the licence, I could post a Scanahand template png and then if someone filled it in I could use Scanahand to get the artwork into a font, which could then be processed using FontCreator.

That could work well if the filling in of the template png were made within a computer, using, say, Microsoft Paint.

However, I am not sure what would happen if I posted a png, someone else printed it out onto paper, filled it in with a pen and then scanned it into his or her computer and then posted it here and I then tried to use it within my copy of Scanahand. The graphic produced by the scanner not being the exact same size in pixels as the template graphic.

Thinking about it I am not quite sure if the scan was not made direct into Scanahand whether there could be synchronization problems if the graphic file of the external scan were not exactly the right size. I do not know, or cannot now remember, how Scanahand locks onto a scan and synchronizes it. Maybe it would work, I am not sure. Anyway, I am not sure that posting a template png is allowed in the licensing rules, though I could check.

Yet the same result could be achieved, though perhaps a bit more laboriously, using FontCreator alone.

Yes, I accept that my meaning was ambiguous. I was thinking in terms of what I have got on this computer.

William

Marcel
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Re: Creating a Tirhuta Keyboard Layout

Postby Marcel » Fri Oct 02, 2015 12:14 pm

Richard W wrote:If anyone wants to help by creating a keyboard, I suggest the following approach:

1) Either use an Inscript (perhaps better, Inscript 5.1) keyboard layout, or convert a Windows Devanagari layout.
Thank you for the roadmap. Effectively I must stick with Devanagari as this is the current hardware for Maithili.
Richard W wrote:2) Squeeze in the unsupported characters - they're useful if you're expecting to use the keyboard for testing fonts, and might actually be necessary for normal text.
Are this the Tirhuta characters that don't have any Devanagari equivalent? Then the layout will be an experimental one and needs to be adjusted.
Richard W wrote:3) If not already included, add ZWJ and ZWNJ just in case they're actually needed. Typical bindings are:

ZWJ: ctrl-shift-1 or altGr-shift-space
ZWNJ: ctrl-shift-2 or altGr-space.
I will add them. No-break spaces as well, but as there are two of them, would it perhaps be interesting to have a dead key on the space bar, say on AltGr+Space? Then we have to map all format and space characters all over the keyboard, as a second keystroke after the dead key. However, as ligatures cannot be used in a dead key sequence—but they can! We've to add both surrogates in a dead key chain! I hadn't had that idea before, hence the exclamation marks.
Richard W wrote:4) Test keyboard on user.
I believe that this is a better way than starting with a specification. Keyboards are tools and cannot be invented in an abstract space. This is why I end up not to make any specification form. We should rather make a prototype, make it available, and wait for feedback.
Richard W wrote:As far as I can see, Tirhuta is mostly just another North Indian extreme font variant. If you need a font to test the keyboard, map Tirhuta to Bengali with some arbitrary mappings for characters that don't correspond.
How do you map one font to another? Is a special tool required? Do I need Font Creator? Perhaps should I make this investment. Until October 04, it is at 149$ or 199$, that is 50 or 100$ off:
http://www.high-logic.com/shop/new-licenses.html

You may download Tirhuta on this other page:
http://www.maithilifonts.in/
Last edited by Marcel on Fri Oct 02, 2015 3:27 pm, edited 1 time in total.

Marcel
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Re: Creating a Tirhuta Keyboard Layout

Postby Marcel » Fri Oct 02, 2015 1:07 pm

William wrote:The link to the font is very useful as there is a link to contact the lady who contributed the font.

So maybe permission, or even help, will be forthcoming so that the converting of a copy of that font to a Unicode font might become possible.
Alas, the e-mail address is not valid any longer. I've just sent an e-mail and got it back for lack of account. We're sadly left alone.

William wrote:I like the art with the leettering. I had not realized that that was possible in this forum.
This is a very performative forum engine, you don't find these features on all fora. Colours may be defined by hex code within the color open-tag, and font-size in percent equally in the size open tag. — When I started on this forum, I wasn't aware of the tags altogether, though I'd read about such tags out there.

I'm going to re-read the explanations that Richard and you posted about the script. Thanks.

Marcel

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Re: How to create Tirhuta (Maithili) Keyboard layout

Postby Marcel » Fri Oct 02, 2015 1:27 pm

William wrote:[...]The Indian languages are each not an alphabet they are each an abugida.
[...]Another issue is the virama.
[...]So we need to find out from Roshan what happens for each of the cases that can occur in the Tirhuta script.
Thank you for these explanations. I've looked up Winipedia on the keywords too, and that there is OpenType glyph substitution. Probably that means that the user has to produce the raw text file and formatting instructions, and the rest is done by the font and the rendering engine, like when we use fraction formatiing and typographic ligatures, that are generated within the word processing software and the font, and not input as characters, the ff, fi, fl,, ffi, ffl in Unicode being for legacy support only (for Word).

Marcel
Last edited by Marcel on Fri Oct 02, 2015 1:48 pm, edited 1 time in total.

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Re: Creating a Tirhuta Keyboard Layout

Postby William » Fri Oct 02, 2015 1:36 pm

Marcel wrote:How do you map one font to another?


With FontCreator it would be straightforward, yet, in this case, possibly laborious.

It is only allowed if you can obtain legal permission to do so.

In the original font each glyph will be mapped to a code point in a range, possibly from $00A0 to $00FF.

So, one would start a new project in FontCreator and insert characters corresponding to the code range for Tirhuta that is in the Unicode chart for Tirhuta. The cells would be empty.

One would then open the existing font and copy each glyph onto the clipboard and paste it into the appropriate cell in the new project. For this task, do not use Paste Special.

One would need to work out, or be informed by someone else, which glyph is which, bearing in mind that the designs may differ from the examples in the Unicode font.

Please note that I said to start a new project in FontCreator and open the old font separately. This is important. It would be unwise to simply open the old font, save as a project and then add the new characters to that project. It might be alright but it might not.

By doing it as I suggest, only the artwork for the glyphs would be copied from the old font, nothing of the internal structure of the old font.

Now it is possible that today, now that FontCreator uses project files, that the problem would not exist. I do not know. Better to be safe than risk it and not know.

The process would be straightforward in relation to using FontCreator. The laborious part is to find out or work out which glyph goes into which cell, though that might be, possibly, easy if, for example, the Unicode mappings are in the same order as the old encoding, then the glyphs could be copied in bulk: getting permission to use the artwork from the original font is important and that depends a lot on whether contact can be made.

The thing is, if someone drew some new glyphs, by drawing by hand and scanning or by designing in either FontCreator or in a graphics program, then the permission part could be easier. Once the designs are in the computer as images then putting them into a font in the right place is straightforward, provided one is told which image goes with which Unicode code point.

William

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Re: How to create Tirhuta (Maithili) Keyboard layout

Postby William » Fri Oct 02, 2015 1:42 pm

Marcel wrote:
William wrote:[...]The Indian languages are each not an alphabet they are each an abugida.
[...]Another issue is the virama.
[...]So we need to find out from Roshan what happens for each of the cases that can occur in the Tirhuta script.
Thank you for these explanations. I've looked up Winipedia on the keywords too, and that there is OpenType glyph substitution. Probably that means that the user has to produce the raw text file and formatting instructions, and the rest is done by the font and the rendering engine, like when we use fracton formatiing and typographic ligatures, that are generated within the word processing software and the font, and not input as characters, the ff, fi, fl,, ffi, ffl in Unicode being for legacy support only (for Word).

Marcel


The thing that concerns me is that whereas f, I and l are all in plane 0 of Unicode, the Tirhuta characters are not in plane 0.

So, for example, one could make a font to do the substitution for the ff, fi, fl,, ffi, ffl and test it in the Serif PagePlus desktop publishing program, as the Serif PagePlus program handles plane 0 Unicode.

How could one test the Tirhuta font?

I only have WordPad that could display the Tirhuta characters, yet it is not OpenType-aware.

William

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Re: How to create Tirhuta (Maithili) Keyboard layout

Postby Marcel » Fri Oct 02, 2015 1:43 pm

Richard W wrote:[...]It can be worse than that.
[...]For vowels like E, there's a form before the consonant (e-) and a form above - say (\e). In Devanagari, they're encoded separately, and the choice should really be a matter of font style. In the Newa script of Nepal, for example, whether 'e' appears before or above the 'pa' depends on the shape of the 'pa' - for some letters it goes before, some it goes above.
[...]Some people, and also fonts, like to think of (p/)(r) as being base letter 'r' with a superscript 'p' following it.

E goes before or on top. U typically goes below or after. O often splits into two pieces, one like E and one after the consonant, as in Tirhuta. I thought I'd keep things simple.
Now I've an idea of what a complex script is. Thank you for this explanation of what I'll be dealing with when trying to map all that to keys! Yes indeed, if the input should be other than what will be in the text file, then an IME would seem the appropriate solution.

However, OpenType fonts allow for scripting, to automatize glyph reordering and glyph substitution. This would be why the keyboard is considered part of a system, along with fonts and rendering engines. Didn't Roshan ask for both font and keyboard layout? How will I go to make one of them, and without knowing Maithili nor Indic on the whole? Well we're talking of a prototype.

Marcel

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Re: How to create Tirhuta (Maithili) Keyboard layout

Postby Marcel » Fri Oct 02, 2015 1:58 pm

Alfred wrote:There is a contact email address on this page.
Alas, the e-mail address is not valid any longer. I've just sent an e-mail and got it back for lack of account. We're sadly left alone.

Sorry I didn't see your post on this page, so I've quoted myself from http://forum.high-logic.com/viewtopic.php?f=16&t=5806&p=26541#p26540

Marcel
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Re: How to create Tirhuta (Maithili) Keyboard layout

Postby Marcel » Fri Oct 02, 2015 2:11 pm

Richard W wrote:
Marcel wrote:A TrueType Tirhuta font is already available for free download:
http://scriptsource.org/cms/scripts/page.php?item_id=entry_detail&uid=ytelv8889u

Unfortunately, changing the cmap table to use Unicode may be illegal.

Alfred in his post below, 15 hours later, pointed to a web page where we read:
http://www.tirhutalipi.4t.com/developersnote.htm wrote:Developers can upgrade the font, without altering the font information. We request them to upgrade adapting a common way, so that we can reach to a standard. Please, let us know about your upgrading through email.
Unfortunately, as already stated twice, the e-mail account does not exist any more.

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Re: Creating a Tirhuta Keyboard Layout

Postby Richard W » Sat Oct 03, 2015 1:44 am

Marcel wrote:How do you map one font to another? Is a special tool required? Do I need Font Creator?

In principle it should be straightforward. One just decompiles the font, edits the resulting source code to change or add the resulting codepoints and, commonly, changes the font name, and then recompiles. There are, however, numerous complications if one wants to preserve all the behaviour:

  1. One may lack a decompiler. I built my own, but it doesn't handle all font tables.
  2. One's compiler may not compile some of the tables.
  3. If one uses GSUB or GPOS tables, one will have to copy the lookups from the original script to the new script. There could be subtle differences in their interpretation between scripts.

I got round problems 1 and 2 by:
  1. decompiling,
  2. modifying the codepoint to glyph maps,
  3. modifying the name table,
  4. recompiling,
  5. replacing the glyf and name tables in the original font by those from the font I've just compiled,
  6. and recalculating the checksums, just in case.

It turned out that I could just have used TTX as the decompiler and compiler. It is a little unfriendly for format 12 cmap tables. You have to provide many unnecessary attributes, so one ends up with an opening tag looking like:

Code: Select all

<cmap_format_12 platformID="3" platEncID="10" format="12" reserved="0" length="1996" language="0" nGroups="165">

Fortunately, it seems that any positive values are acceptable for the length and nGroups attributes.

Marcel
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Re: Creating a Tirhuta Keyboard Layout

Postby Marcel » Sat Oct 03, 2015 1:52 pm

Thank you Richard for the font handling hints. I hope that you or somebody else will get the existing Tirhuta font to be Unicode conformant, ready for the keyboard layouts that will inevitably exist at some future stage of history (if relevant) for Maithili native speakers and scholars all around the world. Personally the font issue is far beyond of what I can do, given that I've never programmed the least standalone software, let alone a compiler. I'm just modifying keyboard driver C sources to some small extent. Here is an idea of what I've been able to do in the meantime:

Iʼve taken the Hindi Traditional Windows keyboard layout, and tried to get Excel match all Tirhuta characters thereupon, on the basis of the Unicode character names. As Richard W expected from the roadmap on, there are unsupported characters in Tirhuta, that do not match to any Devanagari character as present on the Hindi Traditional keyboard layout. As William suggested, Iʼll now post character lists, even if not complete ones, only the ones that are non-obvious to me.

The Tirhuta characters not matching Hindi Traditional Devanagari are the following twelve:

11480 TIRHUTA ANJI
11488 TIRHUTA LETTER VOCALIC RR
11489 TIRHUTA LETTER VOCALIC L
1148A TIRHUTA LETTER VOCALIC LL
114B6 TIRHUTA VOWEL SIGN VOCALIC RR
114B7 TIRHUTA VOWEL SIGN VOCALIC L
114B8 TIRHUTA VOWEL SIGN VOCALIC LL
114BA TIRHUTA VOWEL SIGN SHORT E
114BD TIRHUTA VOWEL SIGN SHORT O
114C4 TIRHUTA SIGN AVAGRAHA
114C5 TIRHUTA GVANG
114C6 TIRHUTA ABBREVIATION SIGN

On the other hand, there are Devanagari characters on the Hindi Traditional Windows keyboard layout that do not match any Tirhuta character. They are listed here:

0949 DEVANAGARI VOWEL SIGN CANDRA O
090D DEVANAGARI LETTER CANDRA E
0945 DEVANAGARI VOWEL SIGN CANDRA E
0911 DEVANAGARI LETTER CANDRA O
0931 DEVANAGARI LETTER RRA
0933 DEVANAGARI LETTER LLA
095F DEVANAGARI LETTER YYA

Now I guess that TIRHUTA LETTER VOCALIC LL and TIRHUTA LETTER VOCALIC RR might match DEVANAGARI LETTER LLA and DEVANAGARI LETTER RRA, which are in Shift of DEVANAGARI LETTER LA and DEVANAGARI LETTER RA on N and J keys, while AltGr places are left empty. So TIRHUTA VOWEL SIGN VOCALIC LL and TIRHUTA VOWEL SIGN VOCALIC RR in turn might take place in the AltGr shift state on these keys. After that, eight Tirhuta characters are left.

The problem with TIRHUTA LETTER VOCALIC L, that prevents it from being treated in the same manner, is that there is also a TIRHUTA LETTER LA, that matches DEVANAGARI LETTER LA, which is in the Base shift state where LLA is in Shift, that is on the N key. There is no other key with an L on Hindi Traditional. However, the key B to the left of LA and LLA is empty in Shift, so that we can put TIRHUTA LETTER VOCALIC L there and TIRHUTA VOWEL SIGN VOCALIC L above in AltGr, correspondingly to the above. After that, half of the unsupported Tirhuta characters are still left:

11480 TIRHUTA ANJI
114BA TIRHUTA VOWEL SIGN SHORT E
114BD TIRHUTA VOWEL SIGN SHORT O
114C4 TIRHUTA SIGN AVAGRAHA
114C5 TIRHUTA GVANG
114C6 TIRHUTA ABBREVIATION SIGN

TIRHUTA VOWEL SIGN SHORT E and TIRHUTA VOWEL SIGN SHORT O can be placed in AltGr on A and S keys above TIRHUTA VOWEL SIGN E and TIRHUTA VOWEL SIGN O which are in Base, and TIRHUTA LETTER E and TIRHUTA LETTER O which are in Shift, matching Devanagari counterparts there.

The TIRHUTA SIGN AVAGRAHA is not special of Tirhuta, as there is a DEVANAGARI SIGN AVAGRAHA too, encoded at U+093D, but not present on the Hindi Traditional keyboard layout as it ships with Windows. However, on the Windows Devanagari Inscript keyboard layout, it is in Shift+AltGr on the Period key, along with DEVANAGARI DOUBLE DANDA in AltGr, that is used in Tirhuta but not present on Hindi Traditional neither, which layout doubles the ASCII period and greater-than in these shift states.

The same applies to TIRHUTA ABBREVIATION SIGN, whose Devanagari version is U+0970 and is on AltGr+Comma on Devanagari Inscript. It can be mapped the same way on Tirhuta keyboard layout.

As for TIRHUTA ANJI by contrast, there is none in Devanagari, but well in Bengali, which script is mentioned as to be close to Tirhuta. But on none of the three Bengali layouts shipped with Windows, there is any U+0980 BENGALI ANJI.

And even more, the TIRHUTA GVANG is unique, as to date, there is no other gvang in any script encoded in Unicode.

Mapping these two characters needs some knowledge about their function and use, so that they may be placed on the appropriate key with respect to ASCII punctuation marks if applicable. There seems to be no ready information on the internet about them. Only based on their glyphic resemblance, I would place them on the same keys together with S (with respect to a stacked double long s) and W.

Then there is a list of characters borrowed from other scripts, additionally to danda and double danda, used in Tirhuta according to TUS §15.10:

09F4 BENGALI CURRENCY NUMERATOR ONE
09F5 BENGALI CURRENCY NUMERATOR TWO
09F6 BENGALI CURRENCY NUMERATOR THREE
09F7 BENGALI CURRENCY NUMERATOR FOUR
09F8 BENGALI CURRENCY NUMERATOR ONE LESS THAN THE DENOMINATOR
09F9 BENGALI CURRENCY DENOMINATOR SIXTEEN
1CF2 VEDIC SIGN ARDHAVISARGA
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

The first six are on the Bengali keyboard in AltGr and Shift+AltGr on A, S, and D keys. Thus there will be a collision with TIRHUTA VOWEL SIGN SHORT E and TIRHUTA VOWEL SIGN SHORT O on the first two keys. The AltGr shift state being mostly empty on letter keys, currency numerators and denominator might be either placed the same way as on Bengali but in the row above, on Q, W, and E keys, or shifted two keys to the right to end up on D, F, and G, or distributed over six keys in the row above, from Q through Y, all in AltGr (which would have been hard to achieve on the Bengali keyboard as there are already several AltGr key positions assigned).

VEDIC SIGN ARDHAVISARGA might be well mapped on the Minus key on which the visarga already is (in Shift), in AltGr because the minus sign there is already available in the Base shift state and has been doubled in AltGr to complete, by the principle of having in the two AltGr shift states the ASCII punctuations following the US-English layout.

To correctly map the North Indic number, quantity and currency signs, a Compose solution is generally the most appropriate. This does not require any dedicated Compose key, because Compose may technically be a simple dead key on whatever key position. This can be on AltGr+Space, because the ZWJ and ZWNJ are on the 1 and 2 keys on the Hindi layout, as Richard W already pointed, so that mapping them on the space bar is not required. This choice is an example of what should be subject to feedback in any case.

The problem with ligatures as a part of dead key sequences is resolved as soon as chained dead keys are available (like when .klc sources or C sources are edited and compiled by KbdUTool or directly by the compilers).

The Tirhuta digits, I suggest to place in the Base shift state, and ASCII digits in AltGr, not conversely as actually on the Hindi traditional layout. The clue is then to convert the unused CapsLock key to a KanaLock, which toggles the layout to a US-English one as currently used in India, following the method that I found yesterday on the KbdEdit web site, except that Tirhuta will be in Base, and English in Kana. If an English with CapsLock is desired (but improbably, given the amount of hate already accumulated on this toggle key by English users), English must be in Base, Tirhuta in Kana, and KanaLock on the uppermost leftmost key, that is not mapped in Hindi Traditional except for the ASCII grave and tilde characters, which will have to be remapped on AltGr+1 and AltGr+2, along with all AltGr key positions outside the letter keys, for some currency and technical characters, section and degree sign and so on.

The Numpad will be equally mapped on all eight shift states (which are ten in fact, if adding Ctrl and Shift+Ctrl, the latter of which is used in Hindi Traditional for ZWJ and ZWNJ). The choice there is between having Tirhuta in Base or in Shift, ASCII in Base or in Shift or in Kana only, and where to have super- and subscripts, hex letters lowercase and/or uppercase, and so on. Currency numerators and denominator may be on the numpad in AltGr shift states, or in Shift above Tirhuta digits, as an alternate solution avoiding dead keys (and the related Compose solution), which are said to be dreadful to many users who are not in the habits of using them. On the other hand, for a numpad without Tirhuta, I can apply the one I have available for French (and as far as the numpad is concerned, for universal Latin). That depends entirely on the expected usage.

But unlike what I supposed, I canʼt do it within one day, even when hoping not to spend one week, as I must finish the French keyboard layout within a useful delay too, and ethically as far as I am concerned---unlike most other people---this is prioritary in my work (however, ethics may turn out to show that I too should prioritize the Tirhuta keyboard layout, in which case I'll conform).

Best,

Marcel
Last edited by Marcel on Mon Oct 05, 2015 10:13 am, edited 1 time in total.

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Re: Creating a Tirhuta Keyboard Layout

Postby William » Sat Oct 03, 2015 4:35 pm

The Unicode code chart is available as follows.

http://www.unicode.org/charts/PDF/U11480.pdf

The Tirhuta characters are U+11480..U+114C7, U+114D0..U+114D9.

Would it be helpful in order to try to implement a keyboard layout to have a special test font as follows?

----

There are characters for U+11480..U+114C7, U+114D0..U+114D9 in the font, as well as a basic English alphabet.

The basic English alphabet is because in my experience fonts that do not have any characters within U+0021..U+007F can get into problems in use.

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.

Such a font could be produced by someone who does not understand Tirhuta script.

----

Would such a special test font help?

Or would it be a distraction from what is trying to be achieved to have such a font produced?

William Overington

3 October 2015

Richard W
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Re: Creating a Tirhuta Keyboard Layout

Postby Richard W » Sat Oct 03, 2015 7:08 pm

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.

DEVANAGARI LETTER RRA is a precomposed letter, so if the equivalent occurred, it would not need its own key.

The lack of a Tirhuti letter LLA is more curious, and might be an omission from the standard. On the other hand, it can be covered by language-specific rules for reading DDA and DDHA as LLA and LL.HA.

Richard.


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