This is the feature selector indicating whether font features are on or off. Table D-9 lists the feature selectors for the kAllTypographicFeaturesType feature type; by specifying the selector kAllTypeFeaturesOnSelector or kAllTypeFeaturesOffSelector for that feature type, you can turn the entire set of features on or off. Note that if you turn all font features off this way, you turn off all
font features, including all the font-specified defaults. (That may result in linguistically incorrect display.) If you turn font features on, you turn on the font-specified defaults, modified by whatever feature settings you have specified in the run-features array.
Table D-9 Feature selectors for the kAllTypographicFeaturesType font feature type
Constant
Explanation
kAllTypeFeaturesOnSelector
Tells ATSUI to use the font features specified in this style run's run-features array and the defaults specified by the font.
kAllTypeFeaturesOffSelector
Tells ATSUI to ignore all font features specified either by the font or in this style run's run-features array.
