Denominators

Tag: dnom

Function: Replaces selected figures which follow a slash with denominator figures. In the string 11/17 selected by the user, the application turns the 17 into denominators when the user applies the fraction feature.

Fractions

Tag: frac

Function: Replaces figures separated by a slash with 'common' (diagonal) fractions. The user enters 3/4 in a recipe and gets the threequarters fraction.

Standard Ligatures

Tag: liga

Function: Replaces a sequence of glyphs with a single glyph which is preferred for typographic purposes. This feature covers the ligatures which the designer/manufacturer judges should be used in normal conditions. The glyph for ffl replaces the sequence of glyphs f f l.

Lining Figures

Tag: lnum

Function: This feature changes selected figures from oldstyle to the default lining form. The user invokes this feature in order to get lining figures, which fit better with all-capital text. Various characters designed to be used with figures may also be covered by this feature. In cases where lining figures are the default form, this feature would undo previous substitutions.

Numerators

Tag: numr

Function: Replaces selected figures which precede a slash with numerator figures, and replaces the typographic slash with the fraction slash. In the string 11/17 selected by the user, the application turns the 11 into numerators, and the slash into a fraction slash when the user applies the fraction feature.

Old Style Figures

Tag: onum

Function: This feature changes selected figures from the default lining style to oldstyle form. The user invokes this feature to get oldstyle figures, which fit better into the flow of normal upper- and lowercase text. Various characters designed to be used with figures may also have oldstyle versions.

Ordinals

Tag: ordn

Function: Replaces default alphabetic glyphs with the corresponding ordinal forms for use after figures. One exception to the follows-a-figure rule is the numero character (U+2116), which is actually a ligature substitution, but is best accessed through this feature. The user applies this feature to turn 2.o into 2.o (abbreviation for secundo).

Proportional Figures

Tag: pnum

Function: Replaces figure glyphs set on uniform (tabular) widths with corresponding glyphs set on glyph-specific (proportional) widths. Tabular widths will generally be the default, but this cannot be safely assumed. Of course this feature would not be present in monospaced designs. The user may apply this feature to get even spacing for lining figures used as dates in an all-cap headline.

Scientific Inferiors

Tag: sinf

Function: Replaces lining or oldstyle figures with inferior figures (smaller glyphs which sit lower than the standard baseline, primarily for chemical or mathematical notation). May also replace lowercase characters with alphabetic inferiors. The application can use this feature to automatically access the inferior figures (more legible than scaled figures).

Superscript

Tag: sups

Function: Replaces lining or oldstyle figures with superior figures (primarily for footnote indication), and replaces lowercase letters with superior letters (primarily for abbreviated French titles). The application can use this feature to automatically access the superior figures (more legible than scaled figures) for footnotes, or the user can apply it to Mssr to get the classic form.

Tabular Figures

Tag: tnum

Function: Replaces figure glyphs set on proportional widths with corresponding glyphs set on uniform (tabular) widths. Tabular widths will generally be the default, but this cannot be safely assumed. Of course this feature would not be present in monospaced designs. The user may apply this feature to get oldstyle figures to align vertically in a column.

Contextual Alternates

Tag: calt

Function: In specified situations, replaces default glyphs with alternate forms which provide better joining behavior. Used in script typefaces which are designed to have some or all of their glyphs join. In Caflisch Script, o is replaced by o.alt2 when followed by an ascending letterform.

Swash

Tag: swsh

Function: This feature replaces default character glyphs with corresponding swash glyphs. Note that there may be more than one swash alternate for a given character. The user inputs the ampersand character when setting text with Poetica with this feature active, and is presented with a choice of the 63 ampersand forms in that face.

Small Capitals From Capitals

Tag: c2sc

Function: Small Capitals From Capitals

Small Capitals

Tag: smcp

Function: This feature turns lowercase characters into small capitals. This corresponds to the common SC font layout. It is generally used for display lines set in Large & small caps, such as titles. Forms related to small capitals, such as oldstyle figures, may be included. The user enters text as mixed capitals and lowercase, and gets Large & small cap text.

Subscript

Tag: subs

Function: The "subs" feature may replace a default glyph with a subscript glyph, or it may combine a glyph substitution with positioning adjustments for proper placement. Recommended implementation: First, a single or contextual substitution lookup implements the subscript glyph (GSUB lookup type 1). Then, if the glyph needs repositioning, an application may apply a single adjustment, pair adjustment, or contextual adjustment positioning lookup to modify its position.

Sylistic Set 1

Tag: ss01

Function: In addition to, or instead of, stylistic alternatives of individual glyphs (see 'salt' feature), some fonts may contain sets of stylistic variant glyphs corresponding to portions of the character set, e.g. multiple variants for lowercase letters in a Latin font. Glyphs in stylistic sets may be designed to harmonise visually, interract in particular ways, or otherwise work together. Examples of fonts including stylistic sets are Zapfino Linotype and Adobe's Poetica. Individual features numbered sequentially with the tag name convention 'ss01' 'ss02' 'ss03' . 'ss20' provide a mechanism for glyphs in these sets to be associated via GSUB lookup indexes to default forms and to each other, and for users to select from available stylistic sets.

Unicase

Tag: unic

Function: This feature maps upper- and lowercase letters to a mixed set of lowercase and small capital forms, resulting in a single case alphabet (for an example of unicase, see the Emigre type family Filosofia). The letters substituted may vary from font to font, as appropriate to the design. If aligning to the x-height, smallcap glyphs may be substituted, or specially designed unicase forms might be used. Substitutions might also include specially designed figures. The user enters text as uppercase, lowercase or mixed case, and gets unicase text.

Tag: lowercase

Function:

Tag: uppercase

Function: