Developing OpenType Fonts
Features are encoded according to both a designated script and language system. There are different language systems defined for the Hindi, Sanskrit, and Marathi languages, although they all use the Devanagari script.
Currently most shaping engine implementations only support the "default" language system for each script. However, font developers may want to build language specific features which are supported in other applications and will be supported in future Microsoft OpenType implementations.
NOTE: It is strongly recommended to include the "dflt" language tag in all OpenType fonts because it defines the basic script handling for a font. The "dflt" language system is used as the default if no other language specific features are defined, or if the application does not support that particular language. If the "dflt" tag is not present for the script being used, the font may not work in some applications.
The following table lists the registered tag names for script and language systems. Note for new Indic shaping implementation “dev2” is used (old-behavior implementations used “deva”).
The MANGAL OpenType font is available to licensed users of VOLT, Microsoft's Visual OpenType Layout Tool. It is provided for illustration only, and may not be altered or redistributed.
MANGAL supports the characters and features in the Unicode Standard, which is a superset of the ISCII-1988 standard. The same Unicode character code layout is followed for nine Indian scripts: Bengali, Devanagari, Gurumukhi (Punjabi), Gujarati, Kannada, Oriya, Malayalam, Tamil and Telugu.
MANGAL is a Windows 2000 system font. MANGAL contains layout information and glyphs to support all of the required features for the scripts and languages supported.
Many shaped glyph forms (such as ligatures) have no Unicode encoding. These glyphs have id's in the font, and applications can access these glyphs by "running" the layout features which depend on these glyphs. An application can also identify non-Unicode glyphs contained in the font by traversing the OpenType layout tables, or using the layout services for purely informational purposes.
MANGAL contains three OpenType Layout tables: GSUB (glyph substitution), GPOS (glyph positioning), and GDEF (glyph definition, distinguishing base glyphs, ligatures, classes of mark glyphs, etc.).
The font is available as part of the VOLT supplemental files. Once you install VOLT you need to run a separate installer to get the supplemental files. Both installers are part of the VOLT download package.
Last updated: September 28, 2009
| shaping engine