Ruwudu is a TrueType font with smart font capabilities added using the OpenType font technology. The Ruwudu font includes a number of optional features that provide alternative rendering that might be preferable for use in some contexts. The sections below enumerates the details of these features. Whether these features are available to users will depend on both the application and the rendering technology being used. Features are available in OpenType. Some applications let the user control certain features such as Stylistic Sets to turn on the rendering of variant characters. However, at this point, many applications do not make use of those features so another solution is needed to show the variant characters. TypeTuner creates tuned fonts that use the variant glyph in place of the standard glyph.

See Using Font Features. Although that page is not targeted at Arabic script support, it does provide a comprehensive list of applications that make full use of the OpenType (and Graphite) font technologies.

See also Arabic Fonts — Application Support. It provides a fairly comprehensive list of applications that make full use of the OpenType font technology.

This page uses web fonts (WOFF) to demonstrate font features and should display correctly in all modern browsers. For a more concise example of how to use Ruwudu as a web font see Ruwudu-webfont-example.html in the font package web folder.

If this document is not displaying correctly a PDF version is also provided in the documentation/pdf folder of the release package.

Signs Spanning Numbers

These signs spanning numbers are intended to enclose or hold one or more digits. Specific technical details of how to use them are discussed in the Arabic fonts FAQ — Subtending marks.

Currently, this font only supports the Number Sign (U+0600) and End of Ayah (U+06DD). Additionally, Ruwudu includes two simplified alternates for U+06DD ARABIC END OF AYAH under the Stylistic Alternates (salt) feature, but at this time we know of no OpenType-based applications that can access these. The two alternates are also available through the Stylistic Sets feature discussed below.

Customizing with TypeTuner

For applications that do not make use of the OpenType Stylistic Sets, you can now download fonts customized with the variant glyphs you choose. Read below about Stylistic Sets, visit TypeTuner Web, choose your preferred variants, and then download your customized font.

Language

Affects: U+065C, U+0627 (with U+064E, U+064F, U+0650), U+063F, U+069F, U+0751, U+0763, U+08C3, U+08C4

Unfortunately, the UI needed to access the language-specific behavior is not yet present in many applications. Some Harfbuzz-based apps, e.g., XeTeX, can access language-specific behavior.

Stylistic Sets

There are some character shape differences in different languages which use the Arabic script. These can be accessed by using the OpenType Stylistic Sets, or through the language support mentioned above.

Imala e (ss04)

Affects: U+065C

Jeem/Hah (ss07)

Affects: U+062C, U+062D, U+062E, U+0683, U+0684, U+08A2

Alef diacritic placement (ss08)

Affects: U+0627, U+064E, U+064F, U+0650

Wagaf (ss09)

Affects: U+063F, U+069F, U+0751, U+0763, U+08C3, U+08C4

End of ayah

Affects: U+06DD

Firefox allows you to use U+06DD followed by the digits and proper rendering occurs. Some applications require the following:

• precede the entire sequence (subtending mark plus following digits) with 202D LEFT-TO-RIGHT OVERRIDE
• follow the entire sequence with U+202C POP DIRECTIONAL FORMATTING.

Surrounding the sequence with U+202D and U+202C seems to give the most reliable results in different browsers. However, we have not found a solution that works in Internet Explorer/Edge.

In the example below, the following codepoints are used: U+202D U+06DD U+0031 U+0032 U+0033 U+202C U+202D U+06DD U+0611 U+0622 U+0663 U+202C.

Proportional Figures

Ruwudu supports the OpenType Proportional Figures (pnum) for Latin digits. This feature is not supported in TypeTuner Web.

Affects: U+0030..U+0039

Contextual Alternates

Ruwudu has a few contextual rules applying subtle differences in the shape and position of certain of the characters depending on context (sometimes shortening, sometimes lengthening or lowering a “tail”). InDesign is able to utilize some of these cross word contextual alternates; however, most applications are not advanced enough to use this behavior in the font. Unfortunately, at this point in the development of the font, combining marks above or below may break these contextual alternates.

Substitutions to avoid collisions in strings with yeh barree character

يِےِ    سِےِ

بؿِےِ    بسِےِ

Note!

If you used previous versions of the Alkalami and Alkalami Light font, we made some decisions which were unfortunately not Unicode compliant. Since the initial release of that font, many of these non Unicode compliant characters have been added to Unicode. This font only supports the Unicode compliant characters. You will need to re-encode some characters to be fully Unicode compliant. The characters affected are listed below: