"Active by default" OT features

charles ellertson's picture

When making a font in FonLab SF5 (i.e., writing the features), is there some way to preset what features are on by default, or is this strictly a matter of the application program (such as InDesign)?

For example, I made up a set of fonts for a book designer, who complained that the ligatures didn't work. We never did trace this down, he just changed fonts. He does use InDesign on a Mac and I use Windows XP; they worked fine on my machine. For all I know, he simply forgot to check the features list in InDesign. But If I could cause certain features to be on when the typeface is selected, that might solve a few problems. I did look in the FL5 index, nothing under "default . . ."

The OT tag registry indicates certain features should be on or off,

>>UI suggestion: This feature serves a critical function in some contexts, and should be active by default.>>

. . . I always assumed that was up to a particular applications program.



Choz Cunningham's picture

AFAIK, these are only guidelines from the OT Specifiers. They are for both type Devs and app devs.

They help the developer of the OT feature set anticipate what an application may do, and application developers understand what might be best for them to choose. Whether or not an OT feature is available and how it is implemented (like defaulting to "on") is up to the application developer.

k.l.'s picture

This is up to the application.

However, in InDesign since version 2 (I think), liga and calt are on by default. Maybe the designer just switched off Ligatures in the paragraph style definition?


twardoch's picture


it is the applications that decide which features are on or off by default, not the fonts.

For standard scripts (Latin, Cyrillic, Greek etc.), the features that typically are on by default and cannot be switched off are: "ccmp", "kern", "mark", "mkmk", "rlig", as well as, for non-default languagesystems, "locl". The features that typically are on by default but can be turned off are: "calt", "clig", "liga".


Choz Cunningham's picture

Adam, that's what I meant, if I wasn't clear. The spec sheets just are there to help the font devs understand what the app devs might be doing.

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