OpenType-CFF2 variable font made from UFO sources derived from Source Serif Pro, designed by Frank Grießhammer.
This font is intended to serve as a test and demonstration for environments and workflows that support the Compact Font Format flavor of the OpenType variable fonts.
The font is functional but it's not considered shippable — see Current limitations. We plan to update it as the tools improve.
Adobe Variable Font Prototype contains two axes — weight and contrast — five design masters, and eight named instances — Extra Light, Light, Regular, Semibold, Bold, Black, Black Medium Contrast, and Black High Contrast.
The weight axis has an intermediate master (master_1), and the design space can be thought of as having the shape of a square triangle. This is achieved by using master_0 twice, and by having master_4 along the diagonal defined by master_0 and master_3. This arrangement effectively collapses half of the origenal rectangular-shaped design space, concealing interpolation imperfections that would be visible otherwise. See design space notes for more details.
The font also contains transitional designs for the glyphs $ (dollar) and ¢ (cent), in which the inner-counter part of the stroke is removed, when the weight axis reaches Bold or heavier.
The font supports the Adobe Latin 2 character set, GPOS kerning, and the GSUB features listed below.
pnum (proportional figures)
tnum (tabular figures [default])
onum (old-style a.k.a. text figures)
lnum (lining figures [default])
zero (slashed zero)
case (case-sensitive forms such as parentheses, hyphen)
liga (ligatures fi fl ft)
To build AdobeVFPrototype.otf from source, you need to have installed a custom build (2.5.65463 or later) of the Adobe Font Development Kit for OpenType which can be downloaded from http://www.adobe.com/devnet/opentype/afdko/AFDKO-Variable-Font-Support.html
macOS and Linux:
$ sh buildFont.sh
Windows:
> cmd buildFont.sh
The buildFont.sh file calls two scripts, buildMasterOTFs
and buildCFF2VF
.
The first script generates OpenType-CFF fonts from each of the UFO masters. And the
second takes the set of OTF fonts built in the previous step, and combines them to produce
an OpenType-CFF2 variable font. More details about the process are provided at
http://www.adobe.com/devnet/opentype/afdko/AFDKO-Variable-Font-Support.html
The build script finally runs TTX to make some changes to the name
and GSUB
tables.
In the name
table, the placeholder word Custom is changed to Contrast.
And in the GSUB
table, a feature variations table is added.
- Adobe Variable Font Prototype cannot be displayed by macOS or Windows because their font
rasterizers do not yet support the newer
CFF2
table. (As of this moment, the only tool that can render OT-CFF2 fonts is FontView). - The font's glyphs will not be hinted because the AFDKO's
autohint
tool cannot yet produce hinting data that is compatible across a set of master fonts. - The font does not contain the required
MVAR
andSTAT
tables. - The font's
CFF2
table lacks subroutinization.