Making necessary OpenType features on by default
Currently, when defining a font feature one has to enable all features by hand which is IMHO not very user friendly as it implies prior knowledge about OpenType font features and the meaning of each one, not every Arabic user, for example, knows what does 'init', 'medi, etc. ligatures mean yet to know that he must enable them to get proper font rendering. I think some font features should be on by default, so that \definefontfeature[script=arabic] should be enough to get an Arabic font rendered correctly with the default features as its designer intended (designers assume that certain will be on while other are off by default, like liga vs. dlig), and if some one wants to disable a certain default feature he can turn it off, not the reverse. Microsoft's OpenType features list page (http://www.microsoft.com/typography/otspec/features_ae.htm) gives a "UI suggestion" for each feature noting if it should be on by default, I think those are what most OpenType enable by default (at least the ones I tested). Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
Khaled Hosny wrote:
i've been thinking of a features=default option (as there is already features=yes|no) even then it can never be fully automatic as some usage of fonts (think of verbatim) demands devation from defaults now, if we implement a default list then we first need to make a detailed list of what the supposed defaults are (and i'm not sure if ms is the only resource for that; after all, not all machineries support all features) a related issue is that fonts can be used for different languages and scripts and therefore a more dynamic feature switching might be needed i.e. arabic might need init, but when the same font is used for latin it not handy to have it enabled, so there might be a matrix of features / scripts needed if it was trivial i'd already done it -) (implementing is trivial but i don't want to make the wrong decision here as it will influence compatibility) Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Fri, 20 Feb 2009 11:57:22 -0700, Hans Hagen
Hmm, not sure if this is a good idea, see below.
i've been thinking of a features=default option (as there is already features=yes|no)
Maybe we can have a features=ms_arabic instead of defaulting to MS' recommendation. So in the final high-end user interface we can have keys like featureset=ms_arabic But I agree with Hans that this is a matter that needs more thought. For example, Traditional Arabic mixes OpenType and older M$ specs in Uniscribe, so just plugging in the default features that M$ suggests is not sufficient for, eg, vowel function in Tr Ar. Also, what about Arabic fonts on the mac, so they follow the same specs as M$? We've still got lots to do before settling on a very high-end interface so there is time to think about this some more... Best wishes Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
On Fri, Feb 20, 2009 at 12:31:49PM -0700, Idris Samawi Hamid ادريس سماوي حامد wrote:
I think the 'ms' part is't really needed, we can just call it"arabic", or are we going to have more Arabic feature sets?
That is beyond OpenType support, since Traditional Arabic is essentially broken at many levels, even when Uniscribe is used (vowel marks break lam-alef ligatures for example), Ms Arabic fonts are special case since they were developed long ago before OpenType and aren't the best examples.
Also, what about Arabic fonts on the mac, so they follow the same specs as M$?
AFAIK, Microsoft's Uniscribe is the reference OpenType implementation, and I assume that Apple's OpenType implementation follows its recommendations (I can't test that).
We've still got lots to do before settling on a very high-end interface so there is time to think about this some more...
Of course, we aren't in hurry. Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
On Fri, 20 Feb 2009 14:02:58 -0700, Khaled Hosny
We are almost certainly going to have more :-)
OTOH there are a lot of arabic fonts like this around that we want to support as well if we can... We a font categorization scheme to fit the most used fonts in the this regard.
This is something we should investigate... uniscribe is quirky in a few areas -- it does extra spell-checking beyond what Arabic actually needs, for example. That's one reason I'm not comfortable with using it as a default standard. Khaled: Have you considered making an inventory of available Arabic fonts? Or does one already exist? We could put together a table of what's available, checking for available OT features, etc. سلام Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
Idris Samawi Hamid ادريس سماوي حامد wrote:
also, it would be nice to have some quality otf arabic fonts in tex live Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Fri, 20 Feb 2009 15:10:52 -0700, Hans Hagen
Why not just include the SIL arabic fonts? http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&item_id=OFL-FAQ_web =============== 1.3 Can I make the fonts available to others from my web site? Yes, as long as you meet the conditions of the license (do not sell by itself, include the necessary files, rename Modified Versions, do not abuse the Author(s)' name(s) and do not sublicense). 1.4 Can the fonts be included with Free/Libre and Open Source Software collections such as GNU/Linux and BSD distributions? Yes! Fonts licensed under the OFL can be freely aggregated with software under FLOSS (Free/Libre and Open Source Software) licenses. Since fonts are much more useful aggregated to than merged with existing software, possible incompatibility with existing software licenses is not a problem. You can also repackage the fonts and the accompanying components in a .rpm or .deb package and include them in distro CD/DVDs and online repositories. =============== Seems similar enough to Texie licences for inclusion. [cc'ing karl] Best wishes Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
Why not just include the SIL arabic fonts? The OFL is fine for a license. TL already has several other OFL'd fonts. If someone puts the fonts on CTAN, I don't mind incorporating them in TL. (As a practical matter, it is a lot of extra work for me to work with any package that is not on CTAN. And besides, we want CTAN to be "comprehensive".) It would also be nice to have supporting TeXish files, but if the bare otf's/ttf's/whatever SIL gives are useful with LuaTeX/ConTeXt, I don't insist.
On Fri, Feb 20, 2009 at 07:57:22PM +0100, Hans Hagen wrote:
I didn't find any other sources, and this seem to be the only published source of such information.
I think we can make default features per script (HarfBuzz seems to do that).
if it was trivial i'd already done it -)
I know :) just my two cents.
(implementing is trivial but i don't want to make the wrong decision here as it will influence compatibility)
I see. -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
Khaled Hosny wrote:
how about making a wiki page where we collect fontnames + assumed default features (+ test if possible); the problem is that fonts themselves don't have that info it's no problem to have a database in mkiv that uses this info so that at some point we can default to a feature set based on font name Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Fri, Feb 20, 2009 at 11:07:08PM +0100, Hans Hagen wrote:
I'll try to do that, though I'm pretty sure that the assumed default features will be what Microsoft recommends, but it is worth more investigation. Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
In fact there are some Persian/Arabic fonts in TL08 and there is no need to include them. They are a part of xepersian package. I think they should be at fonts/truetype/xepersian These fonts include SIL's font in addition to farsiweb fonts. Looking at CTAN, it seems that the author of xepersian is not going to include these fonts in his next release.
Ilda Khaki wrote:
so, arabic user on this list should join forces and make an arabic font package for ctan then (maybe even do a few more sil fonts, like for latin and hebrew and i think that there's also a greek one) Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
Hi Hans, Khaled, and Idris, If a humble opinion from an ordinary user may be issued, I agree with Khaled that it would be extremely useful to have some basic default settings for Arabic fonts, and even more generally for any particular fonts used for other languages. This would not prevent those specialist typesetters who want particular features to be turned on, to do so through appropriate mechanisms. As a basic user I am frustrated when using mkiv, that most declaration of features are completely cryptic, and not being a specialist of OTF or other font specifications, I don't know which features are essential for writing and typesetting an article in Persian or any language using Arabic alphabet. While the following is quite easy to understand and to use in XeConTeXt %%%%%%%%% %!TEX TS-program = xecontext \TeXXeTstate=1 % defining a font for Arabic, Persian \font\Faarsi="Scheherazade:script=arab" at 14pt \Faarsi % defining a font for Roman languages \font\romfont="Times Roman" at 12pt \def\rom#1{{\beginL\romfont #1\endL}} \everypar={\setbox0=\lastbox \beginR \box0 } \starttext \rom{goedemorgen Hans} سلام خالد، درود بر ادریس \stoptext %%%%%%%%%%% it is not so easy to figure out how to typeset the same thing in mkiv: for instance the non specialist has to try several fonts which are installed on his system before getting a result… %%%%%%%%%%% %!TEX TS-program = mkiv \setupdirections[bidi=global] % defining a font for Arabic, Persian \definefontfeature [CrypticFeatures] [analyze=yes, mode=node, language=dflt, script=arab, aalt=yes, init=yes, medi=yes, fina=yes, isol=yes, liga=yes, mset=yes] %\font\Faarsi=Scheherazade*CrypticFeatures at 14pt % this does not work % after trying a few other fonts one finds that the following works: \font\Faarsi=arabtype*CrypticFeatures at 14pt % defining a font for Roman languages \setupbodyfont[12pt] \def\rom#1{{\start \textdir TLT #1 \stop}} \pardir TRT \textdir TRT \starttext \rom{goedemorgen Hans} \start \Faarsi سلام خالد، درود بر ادریس \stop \stoptext %%%%%%%%%%%% The ideal situation would be: • in a document, when one sets a language then a certain font, with certain standard features is set by default; • when an adapted font for that language is defined by the user, then certain features are set by default; • possibly a command like \setupArabic[state=start] [...=...,features=...] (and the analogous settings for other languages such as \setupHanzi[state=start][...=...,features=...], and alike), could be imagined; • for instance, as we have now in ConTeXt, when one has a document written in English, then without even defining a font one can write \starttext goedmorgen Hans! This is some maths formula: $a^2+b^2 = c^2$. \stoptext Therefore, in the same spirit one should have some default allowing the user to write \setupArabic[state=start] \setupHanzi[state=start] \starttext goedmorgen Hans! This is some maths formula: $a^2+b^2 = c^2$. And this is some Arabic text written and typeset from right to left, in the midst of some English text: \startArabic سلام خالد، درود بر ادریس \stopArabic and analogously this is in Hanzi \startHanzi 大家你好 stopHanzi \stoptext I understand that this can be done by each user upon defining his own environment and installing fonts, etc. But for the non specialist it is not that easy to understand the intricacies. With my best regards: OK On 20 févr. 09, at 19:57, Hans Hagen wrote:
On Sat, Feb 21, 2009 at 02:05:01PM +0100, Otared Kavian wrote:
I totally agree with you, more ever I hop that at some point in the future, just selecting certain language will be enough to get proper display of it, some thing like: \mainlanguage[arabic] \startext أهلا بالعالم! \stoptext Should be all what I user need to get an Arabic page. I can even imaging a script analyzer in MkIV that classifies input text and applies fonts/font features per script (Pango kinda does this), with may be some high level commands like: \setupbodyfont[arabic=foo,latin=bar] Which specifies the default font per script. Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
On Sun, 22 Feb 2009 14:03:56 -0700, Khaled Hosny
Fonts will always be complicated... for what you are describing we need to start with a default Arabic-script font for TeX, like LM for Latin. My suggestion is to make Scheherazade that font, since it is free, distributable, and supports nearly all Arabic script languages. We could make two settings: one for Scheherazade as the LM fallback for the needed Ar-script ranges for unicode, another for Scheherazade as the main font, with Termes as Latin fallback. That will give us a benchmark from which to proceed with other fonts. If I get time I'll try to build typescripts etc for this scenario, or Khaled or someone else can take on this task, and I'll review it. Even Scheherazade has lots of options, and it will take some research to get the "ideal" default even here. Best wishes Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
On Sun, Feb 22, 2009 at 03:44:13PM -0700, Idris Samawi Hamid ادريس سماوي حامد wrote:
I'm not very fond if Scheherazade as it has many wrong glyphs (most of the Quranic glyphs are completely wrong) and it doesn't even have an الله ligature, which most Arabic users won't accept. I was experimenting with a modified version that fixes those issues, but I gave up since the font lacks any contextual forms but the basic four ones and extending the font the way it is designed proved to be cumbersome and very error prone. If it is needed, I can clean the font and provide it to be included in the minimal distribution temporarily, as I hope that we'll have a viable alternative by the end of this year. Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
Khaled Hosny wrote:
so, in addition to collecting 'default features per font' we also need to collect info about quality and missing or broken things Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Mon, 23 Feb 2009 05:02:39 -0700, Khaled Hosny
There is a hadith لا يسقط الميسور بالمعسور Scheherazade is certainly not perfect -- and I doubt I'll ever use it personally -- but it's the best freely available option we have. If I understand the license correctly, we can rename it and turn it into a project. You, Otared, and others are expressing the need for a standard, default interface, so let's start with this and build on it. If there is another pure opentype font that is better, let me know and I'll test it. The key point is that SIL has taken care to support nearly every Arabic-script language, not just Arabic, so this gives us a platform that all Arabic-script users can use by default until other free fonts -- or a fork of Scheherazade -- become available. BTW: There is an الله lig in Scheherazade -- rather unattractive, but it's there. Maybe you have an old version?
I'm not sure if the VOLT sources are available, although I used a font-to-volt script that seems to have captured nearly everything. I guess you use FF but no matter: Just make a list of problems and the minimal -- as opposed to ideal -- set of recommended changes and one or both of us can work on this over the next few months. I would also look at Lotus Light -- a simple/simplistic yet probably the most commonly used commercial traditional font in the Arabic and Farsi worlds -- as an ideal default font for general usage. Khaled, note that, although Lotus also has a few contextual forms, in practice it is generally used by publishers without them. BTW: The above is solely for the purposes that Khaled and Otared are pointing out, viz, a default Very High Level Interface for default Arabic script, for use by the average user for general documents, and with little-to-no tweaking. Otherwise, Scheherazade is virtually useless for my own projects.
See the above... make a list of errors in the font and we'll both work on it one way or other. Back to Lotus: I suggest to you and Otared the following project: develop Scheherazade into a free alternative to Lotus. Lotus is that is as close to a pure OpenType font as we are going to easily get. Although it supports less of Arabic-script unicode than Scheherazade, it is a standard in the Arabic-script publishing world. So if our default interface supports Lotus and Scheherazade out of the box, we will be well on our way to what you guys are looking for. سلام ادريس سماوي Idris Samawi -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
On Mon, Feb 23, 2009 at 08:34:54AM -0700, Idris Samawi Hamid ادريس سماوي حامد wrote:
I already have a fork, I just don't want to encourage people to use such aesthetically poor fonts, but as it seems to be the only solution at hand right now (especially the Unicode covering), I think I'll try to clean my font and publish it this week ISA.
BTW: There is an الله lig in Scheherazade -- rather unattractive, but it's there. Maybe you have an old version?
Sorry, yes it has one but is no better than not having one at all.
FF does a great job here, it does read all lookups that I don't need VOLT sources so much.
My initial idea was to extend Scheherazade in a similar way, but I gave up on this, there are so many similar glyphs in the Arabic Unicode block that a simple ligature like بي means 28 (Baa' forms) * 10 (Yaa' forms): 280 glyphs for one ligatures, I don't think this is a wise idea. Regards, Khaled -- Khaled Hosny Arabic localiser and member of Arabeyes.org team Free font developer
On Mon, 23 Feb 2009 10:15:02 -0700, Khaled Hosny
Ok, great!
It's ugly, no doubt, but we can easily replace it, and a couple of the other specials as well. <snip>
Sure, but again لا يسقط الميسور بالمعسور So just start with Arabic, then Farsi, and forget the rest for now. No need for perfection at the outset ;-) Actually, I suggest forgetting about ligatures etc. for now, and just get the basics done for Scheherazade. We can work on ligatures etc later. سلام Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
On Mon, Feb 23, 2009 at 10:56:07AM -0700, Idris Samawi Hamid wrote:
OK, here is an initial version. The glyphs are scaled up since Scheherazade is tiny, fixed الله ligature, added لله and فلله ligatures as well, fixed the swash kaf and the Sindi meem and a bunch of Quranic marks as well: http://www.khaledhosny.org/files/simplenaskhi.zip Regards, Khaled -- Khaled Hosny Arabic localiser and member of Arabeyes.org team Free font developer
On Mon, 23 Feb 2009 15:51:13 -0700, Khaled Hosny
Ok, thnx, Khaled. I looked at it: The الله is infinitely better, but does not quite match the rest -- the shaddah is way too big for it (or maybe the الله lig is too short). On closer inspection, I see that this is not the full الله lig, but a mix of the no-vowel version with the default shaddah. The actual FDF2 looks better. So there is still some OT work that needs to be done. I also have some poetry macros that might help, need to port them to the new system... Not too bad a font. Like Lotus, it works best at smaller text sizes, not greater than 12 point. The فلله lig should be off by default, there are other Arabic word combinations that use that combo that have nothing to do with الله. Next steps: 1. Can I add some fixes to this thing as well or would you like to keep 100% maintainance? 2. I can try to put in some time in the coming weeks to develop this into a default setup for ConTeXt-mkiv -- per recent discussions -- or I can leave that to you/Otared and just review the results. Just let me know how you would like to proceed. سلام Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
On Mon, Feb 23, 2009 at 04:19:13PM -0700, Idris Samawi Hamid ادريس سماوي حامد wrote:
That'd be great!
I can't think in any other word on top of my head, but I'm fine with making it a 'dlig' instead, it isn't very common any way.
Of course you are welcomed, actually I won't have much free time till the end of march, it'd be nice if you can work on it. Regards, Khaled -- Khaled Hosny Arabic localiser and member of Arabeyes.org team Free font developer
On Tue, 24 Feb 2009 13:41:39 -0700, Khaled Hosny
فَلَّلَهُ "he notched or broke it in many places"
but I'm fine with making it a 'dlig' instead, it isn't very common any way.
sure
Ok, let's say whoever gets to it first in the next few days and weeks :-) سلام Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
Khaled Hosny wrote:
to some extend that can already be done with dynamic features but it needs more research etc
\setupbodyfont[arabic=foo,latin=bar]
for that we have the fallbacks mechanism; of course one can mix any font but even then it always demands tuning, i.e. foo and bar can look completely weird when combined without relative scaling (which is what the fallbacks do: thereone chooses one main font and overlays other fonts properly scaled) Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Mon, Feb 23, 2009 at 11:53:30AM +0100, Hans Hagen wrote:
But I think fallbacks are very low level that users shouldn't worry about in general, may be such command can be a higher level interface for font fallbacks. For scaling, we can specify a size, some thing like: \setupbodyfont[arabic=foo,20pt,latin=bar,18pt] or so. Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
On Feb 23, 2009, at 1:09 PM, Khaled Hosny wrote:
I don't know Arabic, but I've done similar things for Greek, and that is not a good interface. You want a scaling factor, so users won't have to worry about scaling in footnotes, titles, etc., an absolute size is not a viable alternative. Thomas
Thomas A. Schmitz wrote:
indeed. btw, i have no problem with a bunch of predefined combinations (using the fallbacks mechanism) so that users can quickly initialize a typeface \usetypescript[fancyarabicwithgreekandtraditionallatin] \setupbodyfont[fancyarabicwithgreekandtraditionallatin,13pt] or so, collected in some type-* file, but that's as far as we can go; we need to guard at least some minimal quality a quick start but with bad output is not the way to go Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Mon, Feb 23, 2009 at 01:28:23PM +0100, Hans Hagen wrote:
I was about to forget why I didn't like font fallbacks in the first place, the current font fallback mechanism assigns fonts per Unicode characters, this is fine until we come to common characters like numbers or brackets: you can only assign it to one font, which isn't usually desirable. Think of this sentence: عربي 1234 عربي (English 1234 English (English) English) عربي. Here, the outer most parentheses and first numbers should use the same font of the Arabic text, while the inner ones should use the font of the English text, font fallback can't do this. Instead we need to segment the text per script and apply fonts on whole segments, the Unicode Script Property annex describes a way to handle this, see http://www.unicode.org/reports/tr24/#Script_Names_in_Rendering. Regards, Khaled -- Khaled Hosny Arabic localiser and member of Arabeyes.org team Free font developer
On Mon, Feb 23, 2009 at 06:01:35PM +0100, Taco Hoekwater wrote:
Sure I can do, but I was talking about some kind of automatism, for example I'm trying some books written in DocBook, and want ConTeXt to automate the typesetting process as possible. It is also cumbersome to markup every Arabic/English part of the text, especially for Arabic technical documentation where Arabic and non Arabic text are mixed very often. Regards, Khaled -- Khaled Hosny Arabic localiser and member of Arabeyes.org team Free font developer
Khaled Hosny wrote:
Sure but that can be done by using explicit switches to another 'environment' i.e. explicitly marking sections I'm not that sure if i want to add some fuzzy automatism which then needs to handle all kind of exceptions too proper markup is a good solution Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Mon, 23 Feb 2009 16:23:59 -0700, Hans Hagen
Not sure I understand you, but could we do something like the following: Along the lines of \quote, \quotation: Latin text\paren{here is some arabic text\paren[somefallback]{here is some latin} more arabic}. so the fallback will be used when explicitly called. Put another way, could we add a conditional parameter to the fallback macro so that those chars are used only in situations when they are specifically called? \paren[fallback=...] \bracket[fallback=...] \brace[fallback=...] \anglebracket[fallback=...] Best wishes Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
Idris Samawi Hamid wrote:
sure, it makes sense to add that kind of structure ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Mon, Feb 23, 2009 at 01:17:42PM +0100, Thomas A. Schmitz wrote:
I think ConText defines footnote and other font sizes relative to body font, no? I'm not defending my idea either, I'm OK with whatever being better. Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
Hi Otared,
On Sat, 21 Feb 2009 06:05:01 -0700, Otared Kavian
sure, but it needs some thought. As I mentioned in my latest reply to Khaled, we can start with Scheherazade as an initial benchmark and proceed from there.
The difference -- I think -- is that xetex uses the system libraries. Uniscribe is not configurable, so you're stuck with however uniscribe interprets the ot features. <snip>
%\font\Faarsi=Scheherazade*CrypticFeatures at 14pt % this does not work
Hmm, I wonder why...
sure, I suggest Scheherazade
• when an adapted font for that language is defined by the user, then certain features are set by default;
that needs some research, for reasons Hans has explained.
sure
For now the focus is getting OpenType and the mid-level interface solid, then we can focus on the high-level interface as you have described. OTOH, Getting Scheherazade (or some other mutually agreed-upon font) set up as default with a high-level interface should not be that hard. سلام Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
Hi,
On Sat, 21 Feb 2009 06:05:01 -0700, Otared Kavian
%\font\Faarsi=Scheherazade*CrypticFeatures at 14pt % this does not work
The following works here: % engine=luatex \definefontfeature [scheherazade-test] [analyze=yes,mode=node, language=dflt,script=arab, ccmp=yes, init=yes,medi=yes,fina=yes, rlig=yes, calt=yes, salt=yes, curs=yes, mark=yes, mkmk=yes] \font \Scheherazademk = ScheherazadeRegOT*scheherazade-test at 28pt \setcharactermirroring[1] \noheaderandfooterlines \Scheherazademk \starttext سلام خالد، درود بر ادریس \stoptext -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
Hi Hans, Khaled, and Idris, If a humble opinion from an ordinary user may be issued, I agree with Khaled that it would be extremely useful to have some basic default settings for Arabic fonts, and even more generally for any particular fonts used for other languages. This would not prevent those specialist typesetters who want particular features to be turned on, to do so through appropriate mechanisms. As a basic user I am frustrated when using mkiv, that most declaration of features are completely cryptic, and not being a specialist of OTF or other font specifications, I don't know which features are essential for writing and typesetting an article in Persian or any language using Arabic alphabet. While the following is quite easy to understand and to use in XeConTeXt %%%%%%%%% %!TEX TS-program = xecontext \TeXXeTstate=1 % defining a font for Arabic, Persian \font\Faarsi="Scheherazade:script=arab" at 14pt \Faarsi % defining a font for Roman languages \font\romfont="Times Roman" at 12pt \def\rom#1{{\beginL\romfont #1\endL}} \everypar={\setbox0=\lastbox \beginR \box0 } \starttext \rom{goedemorgen Hans} سلام خالد، درود بر ادریس \stoptext %%%%%%%%%%% it is not so easy to figure out how to typeset the same thing in mkiv: for instance the non specialist has to try several fonts which are installed on his system before getting a result… %%%%%%%%%%% %!TEX TS-program = mkiv \setupdirections[bidi=global] % defining a font for Arabic, Persian \definefontfeature [CrypticFeatures] [analyze=yes, mode=node, language=dflt, script=arab, aalt=yes, init=yes, medi=yes, fina=yes, isol=yes, liga=yes, mset=yes] %\font\Faarsi=Scheherazade*CrypticFeatures at 14pt % this does not work % after trying a few other fonts one finds that the following works: \font\Faarsi=arabtype*CrypticFeatures at 14pt % defining a font for Roman languages \setupbodyfont[12pt] \def\rom#1{{\start \textdir TLT #1 \stop}} \pardir TRT \textdir TRT \starttext \rom{goedemorgen Hans} \start \Faarsi سلام خالد، درود بر ادریس \stop \stoptext %%%%%%%%%%%% The ideal situation would be: • in a document, when one sets a language then a certain font, with certain standard features is set by default; • when an adapted font for that language is defined by the user, then certain features are set by default; • possibly a command like \setupArabic[state=start] [...=...,features=...] (and the analogous settings for other languages such as \setupHanzi[state=start][...=...,features=...], and alike), could be imagined; • for instance, as we have now in ConTeXt, when one has a document written in English, then without even defining a font one can write \starttext goedmorgen Hans! This is some maths formula: $a^2+b^2 = c^2$. \stoptext Therefore, in the same spirit one should have some default allowing the user to write \setupArabic[state=start] \setupHanzi[state=start] \starttext goedmorgen Hans! This is some maths formula: $a^2+b^2 = c^2$. And this is some Arabic text written and typeset from right to left, in the midst of some English text: \startArabic سلام خالد، درود بر ادریس \stopArabic and analogously this is in Hanzi \startHanzi 大家你好 stopHanzi \stoptext I understand that this can be done by each user upon defining his own environment and installing fonts, etc. But for the non specialist it is not that easy to understand the intricacies. With my best regards: OK On 20 févr. 09, at 19:57, Hans Hagen wrote:
Otared Kavian wrote:
well, it might be easy to understand given that default features are enabled but on the other hand,. when you want to disable a feature you need to know what is enabled so in practice you have the same problem i remember a talk at bachotex about apps dealing with open type where compatibility problems showed up when the machinery started to support more features, or started to make relationships between features and scripts since tex is supposed to behave in a predictable way, any automatism should be visible and basically be on user request so the only way to go is by predefined (and agreed upon) features sets, possible different defaults per script/language
\everypar={\setbox0=\lastbox \beginR \box0 }
not that user friendly, and it would break much other functionality in context -)
that's why we need an inventory, else it will always be a gamble and surprise what one will get ... (also feature creep is a problem ... i really dislike all those documents with funny ancient ligatures that just show up because they're enables, even if they make no sense any more)
that depends on what Scheherazade supports
mtxrun --script font --list --info --pattern=scheherazade
MtxRun | fontname: scheherazade MtxRun | fullname: Scheherazade MtxRun | filename: scheherazaderegot.ttf MtxRun | MtxRun | feature: calt, script: arab, language: kur snd urd dflt MtxRun | feature: ccmp, script: arab, language: kur snd urd dflt MtxRun | feature: curs, script: arab, language: kur snd urd dflt MtxRun | feature: fina, script: arab, language: kur snd urd dflt MtxRun | feature: init, script: arab, language: kur snd urd dflt MtxRun | feature: mark, script: arab, language: kur snd urd dflt MtxRun | feature: medi, script: arab, language: kur snd urd dflt MtxRun | feature: mkmk, script: arab, language: kur snd urd dflt MtxRun | feature: rlig, script: arab, language: kur snd urd dflt MtxRun | feature: salt, script: arab, language: kur snd urd dflt so, it seems to depend on calt but turning on calt by default is *not* what the ms spec recommends for arabtype you see the problem? we need a database and even then agree upon the defaults; when we have that we can default (per font/script/lang) to a featureset ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Mon, Feb 23, 2009 at 11:42:41AM +0100, Hans Hagen wrote:
Yes, but the majority if people want need that, if I want to play with OpenType features then I'm supposed to know what I'm doing, while most people will be happy with the default features (given it is a reasonable default of course.) [...]
I think is is arabtype's problem if they suggest turning calt off by default, if I've contextual alternatives in my font this means I think those alternatives are necessary to render text correctly, otherwise I would have used a stylistic set. Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
On Mon, Feb 23, 2009 at 02:25:15PM +0200, Khaled Hosny wrote:
I just checked arabtype font, and I don't see why one would suggest turning 'calt' off by default, it doesn't make any sense to me; many necessesary features (like rising the second tooth in words like بيت) are 'calt' features. Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
Khaled Hosny wrote:
it's not arabtype that suggests it, thats the problem; open type fonts *don't* have any information about what features should be on by default; it's the renderers that kind of decide it and there is no standard, so any renderer will follow its own rules also, some features (like frac) are often implemented only partial and as such can only be applied very selectively so, the only way out is something: defaults{'arabtype'] = { arab = { dflt = { calt=true, mkmk=true, ...}, }, } a kind of database Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
Khaled Hosny wrote:
I think some font features should be on by default, so that \definefontfeature[script=arabic] should be enough to get an Arabic font
btw, this is why we already have arabic as featureset defined ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Fri, Feb 20, 2009 at 07:58:11PM +0100, Hans Hagen wrote:
I wasn't aware of that, I think having a set of predefined features would be perfectly OK, just if one can reuse it: some thing like \definefontfeature[include=arabic], may be some thing like that is already implemented? Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
Khaled Hosny wrote:
indeed, for instance there is an arabic predefined (not sure if it's ok) which you can extend if needed: \definefontfeature[myarabic][arabic][rlig=yes] in typescripts and font definitions you can just use 'myarabic' \definedfont[arabtype*myarabic] \definetypeface.........[features=arabic] etc etc ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Fri, 20 Feb 2009 11:39:23 -0700, Khaled Hosny
Hmm, I think this page is more relevant for what you have in mine: http://www.microsoft.com/typography/otfntdev/arabicot/features.htm :-) سلام Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
Idris Samawi Hamid ادريس سماوي حامد wrote:
watch the "The standard order for applying Arabic features encoded in OpenType fonts" ... an earlier mkiv otf handler did this but then we found out that it violates the otf 'any order possible' rule so now we do just the order as we encounter it (and even then it took us a while to figure out where/how to avoid interferences); so ... it's up to the font designer (or technician) now, having init, medi, fina, isol, rlig enabled might be the default, but for instance arabtype output looks much better when instead of rlig we use calt/clig etc so, in that case the defaults would bot be the best choice; again an argument for a database approach there are even fonts out there that have the right gsub/gpos info but lack the feature being listed in the script/lang dictionary which is complicating live even more; maybe we should assume that the renderers of ms and adobe have some additional built in heuristics of using specific fonts Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
On Sat, Feb 21, 2009 at 12:41:48PM +0100, Hans Hagen wrote:
IIRC, the 'ccmp' should be applied before any other lookup, the rest are applied as they are ordered in the font, at least this makes sense more.
Arabic Typesetting is a quit a special case font, though I believe that 'calt' and 'clig' should be on by default for any font.
Any links to such fonts? Looks interesting. Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
On Sun, 22 Feb 2009 13:54:51 -0700, Khaled Hosny
It is not the order of the features, but the order of the lookups that really counts here. So, more precisely, the lookups in ccmp should be defined in the font before all other lookups. See also http://www.microsoft.com/typography/otfntdev/arabicot/shaping.htm http://www.microsoft.com/typography/otfntdev/arabicot/default.htm
That's just it, there are so many exceptional cases it's not trivial to define a rule. Again, Scheherazade seems appropriate as a place to start... I will try to find some time in the next month to work on this, or someone can start and Hans and I can complete the module.
Hans may be referring to hybrids like Traditional Arabic.... Best wishes Idris -- Professor Idris Samawi Hamid, Editor-in-Chief International Journal of Shi`i Studies Department of Philosophy Colorado State University Fort Collins, CO 80523
On Fri, Feb 20, 2009 at 03:46:50PM -0700, Idris Samawi Hamid ادريس سماوي حامد wrote:
Though it doesn't suggest what should be on/off by default, I think it is a good starting point. From the features listed there, I think only 'dlig' and 'cswh' don't make much sense to be on by default, so I think the predefined 'arabic' font features should be changed to disable 'dlig' and enable 'calt' and 'mset' instead, as I think both are needed for Arabic fonts (especially 'calt' which is heavily used in Nasta'liq fonts). So, I think it should be: \definefontfeature [arabic] [mode=node,language=dflt,script=arab, init=yes,medi=yes,fina=yes,isol=yes, liga=yes,rlig=yes,clig=yes,calt=yes, mark=yes,mkmk=yes,kern=yes,curs=yes, mset=yes] Regards, Khaled -- Khaled Hosny Arabic localizer and member of Arabeyes.org team
participants (9)
-
Hans Hagen -
Idris Samawi Hamid -
Idris Samawi Hamid ادريس سماوي ح امد
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Ilda Khaki -
karl＠freefriends.org -
Khaled Hosny -
Otared Kavian -
Taco Hoekwater -
Thomas A. Schmitz