Bringing ᬅᬓᬱᬭᬩᬮ to ios. Norbert Lindenberg

Transcription

1 Bringing ᬅᬓᬱᬭᬩᬮ to ios Norbert Lindenberg Norbert Lindenberg 2015

2 Building blocks for the multilingual Web Internationalization at Wikipedia Alolita Sharma Director of Engineering Internationalization and Localization Wikimedia Foundation San Francisco Globalization Meetup, May 2, CC BY SA 3.0 2

3 Why? Wikipedia and many others need support for many/all writing systems Operating systems focus on most popular writing systems but increasingly enable third parties to add support Fonts and keyboards are core 3

4 Bringing ᬅᬓᬱᬭᬩᬮ to ios Norbert Lindenberg Norbert Lindenberg 2015

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6 Balinese script

7 Balinese Balinese language spoken in daily life by about one million people For writing, largely replaced by Indonesian, or written in Latin script Balinese script taught in schools, but rarely used in daily life 7

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10 Balinese script Used to write Balinese, Sanskrit, Sasak Derived from Old Kawi, Pallava, Brahmi Has structure and complexity similar to other Brahmic scripts 10

11 Abugida Consonants have default vowel /a/ ᬳ: ha ᬦ: na ᬘ: ca 11

12 Dependent vowels Dependent vowels override default vowel Can attach on all sides of consonant ᬳ + ᬳ : hi ᬳ + ᬳ : hu ᬳ + ᬳ: he ᬳ + ᬳ : ho 12

13 Pre-base vowels Dependent vowels override default vowel Can attach on all sides of consonant ᬳ + ᬳ : hi ᬳ + ᬳ : hu ᬳ + ᬳ: he ᬳ + ᬳ : ho 13

14 Conjuncts Default vowel can be suppressed by using conjunct form of following consonant Represented in Unicode by inserting ᬓ + + ᬱ ᬓᬱ: ksa ᬗ + + ᬓ ᬗᬓ: ngka 14

15 Independent vowels Initial vowel usually written with ᬳ, but independent vowels also available ᬅ: a ᬇ: i ᬉ: u 15

16 Contextual forms Conjuncts Mark groups ᬳ + + ᬳ Tedung ligatures ᬳ + ᬳ 16

17 Contextual forms Conjunct-conjunct ligatures: ᬲ + + ᬢ + + ᬭ ᬲᬢᬭ Conjunct-vowel ligatures: ᬦ + + ᬬ + ᬦᬬ 17

18 Mark positioning Above-base marks ᬳ + + ᬳ Below-base marks ᬳ + ᬳ ᬦ + + ᬤ + ᬦᬤ 18

19 Balinese in Unicode

20 Unicode Balinese added in Unicode 5.0 in 2006 Thanks to Michael Everson, I Made Suatjana, local experts, and the Script Encoding Initiative 20

21 Balinese font for ios

22 Terminology Character: smallest component of written language that has semantic value. Example: A Glyph: shape for displaying character, part of character, or combination of characters. Examples: A A A A A A A A A A A,, fi Unicode has characters; fonts have glyphs 22

23 Font technologies All known Balinese fonts packaged in TrueType containers Core tables: Glyphs: glyf (TrueType), CFF (PostScript) Character-to-glyph mapping: cmap Different ways to support complex features 23

24 Hacked fonts Large set of glyphs, often for complete grapheme clusters Hacked, font-proprietary encoding Custom keyboard to build up grapheme clusters Not compatible with any text processing other than rendering 24

25 Apple Advanced Typography Font can/must provide all necessary information for script handling morx tables to reorder glyphs or replace sequences of glyphs with others kerx + ankr tables to position glyphs 25

26 Apple Advanced Typography OS X and ios only Best supported solution for these platforms 26

27 OpenType Rendering engine provides information generic to script; font provides details Reordering pre-base vowels is generic ( ) GSUB tables to substitute glyphs GPOS tables to position glyphs 27

28 OpenType Supported to varying degrees on many platforms, including ios Balinese supported: in HarfBuzz (Firefox, Android, Java 9) in Windows 10 (Universal Shaping Engine) not in ios 28

29 Existing Balinese fonts Font Technology Contextual Forms License Bali Simbar Hacked Some? JG Aksara Bali Hacked Many? Aksara Bali OpenType Many? Noto Sans Balinese OpenType Few Apache 29

30 Adapting font for ios Font Technology Contextual Forms License Bali Simbar Hacked Some? JG Aksara Bali Hacked Many? Aksara Bali OpenType Many? Ubud OpenType + AAT Few Yes 30

31 Naming glyphs Glyph IDs are too hard to work with post table: glyph names Adobe Glyph List recommendation uni1b33 uni1b44_uni1b33 uni1b44_uni1b26.shallow 31

32 Defining glyph classes Glyph classes used in most AAT tables Could be partially based on USE definitions B uni1b13 uni1b14 uni1b15 uni1b16 GB uni00a0 uni25cc H uni1b44 VPre uni1b3e uni1b3f 32

33 Pre-base vowels Dependent vowels override default vowel Can attach on all sides of consonant ᬳ + ᬳ : hi ᬳ + ᬳ : hu ᬳ + ᬳ: he ᬳ + ᬳ : ho 33

34 Reordering pre-base vowels State-action table EOT OOB B VPre StartText SawBase Action table GoTo MarkFirst? MarkLast? Advance? DoThis 1 StartText no no yes none 2 SawBase yes no yes none 3 StartText no yes yes xd->dx 34

35 Forming conjuncts Simple ligature table List uni1b44_uni1b0b uni1b44 uni1b0b uni1b44_uni1b0c uni1b44 uni1b0c uni1b44_uni1b13 uni1b44 uni1b13 uni1b44_uni1b14 uni1b44 uni1b14 35

36 Positioning glyphs Uses two tables: ankr and kerx ankr defines anchor points for glyphs kerx defines which anchor points to use in which context ᬳ + + ᬳ 36

37 ᬳ ᬓ ᬅᬓᬱᬭ ᬦ ᭔᭗ ᬮᬯ ᬳ ᬧ ᬦ ᬅᬓᬱᬭᬲᬯᬭ ᭑᭔ ᬅᬓᬱᬭᬯᬬᬜᬚᬦ ᭓᭓ ᬅᬓᬱᬭᬲᬯᬭᬧ ᬦ ᬓᬢᬍ ᬤ ᬤ ᬲᬧᬗ ᬗᬕᬲᬯᬭ ᬢ ᬫᬤ ᬯᬲᬯᬭ ᬓᬓᬮ ᬓᬯ ᬱᬝᬦ ᬦ ᬲᬯᬭᬳ ᬲᬯᬫ ᬯ ᬤ ᬖ Source:

38 Installing fonts on ios Fonts can be part of configuration profile Other parts mostly enterprise stuff: network configuration, disabling web sites, etc. Safari and Mail recognize and install profiles App installs profile by running web server and sending URL to Safari 38

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40 Where does Ubud font work? All apps using standard ios text rendering Safari and Webkit-based apps, in ios 8.3 Not in Microsoft Word 40

41 Balinese keyboard for ios

42 Keyboards in ios ios 8 provides keyboard extension API Keyboard extension is packaged in containing app User enables keyboard in Settings User selects keyboard within host apps 42

43 Design considerations Nobody really has experience typing Balinese; QWERTY is irrelevant No popups above top row Practical limits: 4 10 iphone, 4 12 ipad 43

44 Design considerations 121 Balinese Unicode characters 28 musical symbols 7 specific to Sasak 11 redundant many others rarely used Also: Return, Space, Delete, Next Keyboard, Next Layer, Dismiss 44

45 ipad: 2 layers 45

46 iphone: 3 layers 46

47 Pre-base vowels Dependent vowels override default vowel Can attach on all sides of consonant ᬳ + ᬳ : hi ᬳ + ᬳ : hu ᬳ + ᬳ: he ᬳ + ᬳ : ho 47

48 Pre-base vowels Users want to type pre-base vowels before base Input Unicode Display U+200B U+1B3E ᬳ U+1B33 U+1B3E ᬳ 48

49 Installing keyboards

50 Balinese Font and Keyboard app

51 Further reading Bringing Balinese to ios norbertlindenberg.com/2015/05/bringing-balinese-to-ios/ 51