PATH Mac OS 8 and 9 Developer Documentation > Text and Other International Services > Apple Type Services for Unicode Imaging (ATSUI) > Apple Type Services for Unicode Imaging Reference

Diacritical Mark Font Feature Selector Constants

A glyph with a diacritical mark is a form of ligature. For fonts whose glyphs can take diacritical marks, ATSUI allows you several display options. If the font supports the diacritical marks feature type, you can specify that ATSUI should show, hide, or decompose diacritical marks, as shown in Table D-7.

Table D-7 Feature selectors for the kDiacriticsType feature type

Constant	Explanation
`kShowDiacriticsSelector`	Specifies that ATSUI is to form accent ligatures on the glyphs they apply to.
`kHideDiacriticsSelector`	Specifies that ATSUI is not to form any accent ligatures.
`kDecomposeDiacriticsSelector`	Specifies that ATSUI is to display marked glyphs as unmarked, followed by the accent ligatures as stand-alone glyphs.

For Roman fonts the default setting is to show diacritical marks. In text for scripts in which vowel marks are not normally shown, you can specify that marks be visible in certain instances, such as for children's text, or for pronunciation guides on rare words. Figure D-3 shows an example of Hebrew text drawn with and without its diacritical marks.

Figure D-3 Hebrew text with diacritical marks shown (upper) and hidden (lower)

Figure D-4 shows an example of text drawn with and without its accents.

Figure D-4 Accented forms