Smart Font Features
Nastaliq style Arabic is one of the most complex forms of writing in the world, and standard font technologies are not quite up to the challenge of handling its sloping, calligraphic form. For this reason, SIL’s smart-font technology, Graphite, has been extended with some special capabilities to address the particular challenges of this beautiful but complicated form of writing.
The sloping nature of Nastaliq creates a great challenge: glyph collisions. A straightforward, naive layout of base glyphs, nuqtas, and diacritics will inevitably result in a rendering where the glyphs collide, forming ugly and even unreadable text. Fixing these collisions is exacerbated by the large number of glyphs and the complex positioning created by the sloping baseline.
Workarounds to current font technologies have been used to create Urdu-specific fonts, but these approaches do not scale well when multiple languages and a variety of diacritics are needed. For this reason, SIL International has developed Awami Nastaliq, specifically intended to support lesser-known languages of Southwest Asia (using an extended version of Graphite). While there are several fonts that support Urdu, this is the first Nastaliq-style font that supports a wide variety of lesser-known languages.
To solve the problem of collisions, we have enhanced Graphite with an automatic collision-fixing capability. The Graphite engine makes use of a simplified form of the rendered glyphs to detect collisions, shift nuqtas and diacritics, and add kerning to create nicely laid-out text. Besides fixing collisions, the shape-based kerning mechanism can also create diagonal overlaps in the sloping text, as Nastaliq is traditionally written.
We have added a number of user-selectable variations in Awami Nastaliq. These include:
- Hook on medial heh‐goal: some Nastaliq writers omit the hook on the medial heh-goal forms, while others include it
- Initial heh doachashmee: heart-shape (default) vs. round/tear-drop shape
- Lam with V: V over stem vs. V over bowl
- Full stop: Dash vs. Dot
- Punctuation: Arabic vs. Latin
- Sukun/jazm: inverted V vs. comma shape
- Hamza: Urdu style hamza vs. Arabic style
- Word spacing: extra tight, tight, medium (default), wide, extra wide
- Short forms: none, kafs and gafs, finals, all
- Collision avoidance: off, on, kern-only
- Small nuqtas: off vs. on
- Show invisible characters: invisible vs. visible
Awami Nastaliq supports these styles by means of user-selectable features.
The User-selectable font features are demonstrated using .woff support on this page: Awami Nastaliq Features Demo.
Vowel diacritical marks
Few Nastaliq style fonts handle vowel marks well. This is acceptable for Urdu, but not for other languages, such as Saraiki and Marwari, that make more extensive use of vowel marks. Awami Nastaliq provides good support for the vowel marks often used by other languages.