ss01–ss20 — Stylistic Sets
ss01–ss20 (Stylistic Set 1–20) each replace a meaningfully labeled set of glyphs with another, coordinated set.
They switch a set of glyphs, spanning several characters, designed to harmonize with each other — for example, giving the entire lowercase alphabet of a Latin font a different, visually unified design. Zapfino Linotype and Adobe Poetica are examples of typefaces with stylistic sets like these.
Example
Section titled “Example”.fea source
Choosing among the alternate-glyph features
Section titled “Choosing among the alternate-glyph features”Three features give access to alternate glyphs, ss01–ss20 among them.
| Feature | Purpose |
|---|---|
aalt |
Gathers all the alternates of a selected glyph and lets the user choose among them |
salt |
Replaces the default glyph with an alternate chosen for the typeface’s stylistic design |
ss01–ss20 |
Replaces a meaningfully labeled set of glyphs with another, coordinated set |
Aesthetic alternates for an individual glyph are salt’s territory. ss01–ss20 target a set of glyphs instead.
Each set can carry a human-readable description in a featureNames block. The font stores that string in the name table, and an application can show it as a menu label (Adobe OpenType Feature File Specification, §8.c). This is the mechanism that gives ss01–ss20 alternates their meaning.
Writing it in a feature file
Section titled “Writing it in a feature file”The rules are written with Lookup Type 1.