Features
- Try to read `SOURCE_DATE_EPOCH` variable from the environment if the
`openTypeHeadCreated` is not set in fontinfo.plist (199).
- Added optional `FlattenComponentsFilter` to un-nest composite glyphs (214).
- Added optional `PropagateAnchorsFilter` to recursively copy all anchors from
the components' base glyphs to the composite glyph that reference them (223).
NOTE: the anchor propagation for composite ligature glyphs is problematic and
may change in future versions.
- Optimize CFF table's size by choosing optimal default/nominalWidthX (227,
216).
- No longer write a fallback value for the CFF `Weight` operator in TopDict if
`postscriptWeightName` is not set in fontinfo.plist. The value is not
required in the CFF spec (239).
- Changed feature writers API to update a pre-parsed `feaLib.ast.FeatureFile`
Abstract Syntax Tree (AST) object, instead of generating strings. See this
https://github.com/googlei18n/ufo2ft/pull/255#issuecomment-391457046, as
well as the inline docstrings for the BaseFeatureWriter class for more
information (255).
- The old `FeatureCompiler` class has been split into an `MTIFeatureCompiler`
for MTI features, and a `FeatureCompiler` for Adobe FDK features only; the
previous name was kept for backward compatibility.
- The `FeatureCompiler` now loads custom feature writers as specified in the
UFO lib under a special key "com.github.googlei18n.ufo2ft.featureWriters".
This is a plist array of dictionary elements; each dict has a required
"class" name, an optional "module" and "options" (dictionary) that are
passed as keyword arguments to the class constructor. These can be used
to override the default feature writers' configuration or load custom
feature writer modules. An empty array disables auto-features generation.
- Removed deprecated `kernWriterClass` and `markWriterClass` arguments in
top-level compile functions. Replaced by an equivalent `featureWriters`
argument: an optional list of feature writer classes or pre-initialized
instances that overrides both the default writer classes and the ones
specified in the UFO lib.
- `KernFeatureWriter` was rewritten to support the new AST-based approach, and
to implement some new features, including: support for Indic-specific `dist`
feature; improved the algorithm for splitting RTL and LTR kerning lookups,
using the fonttools subsetter's to perform a closure over the GSUB table
and resolve LTR/RTL glyph alternates; Arabic numerals are now correctly kerned
from left to right following their BiDi type, while added only to the RTL
lookup (255, 176, 198).
- `MarkFeatureWriter` was rewritten from scratch, and now supports
Indic-specific `abvm` and `blwm` features (257, 179).
- Use the UFO's path to resolve the relative `include` statements in features,
not the embedded features.fea file itself (unified-font-object/ufo-spec55,
googlei18n/fontmake157).
- Added `compileFeatures` function that takes a UFO and compile the OTL
features into either an existing TTFont object, or creates a new TTFont only
containing the newly built OTL tables.
- The `OS/2.usMaxContext` calculation was moved from the `FeatureCompiler` to
the `PostProcessor` class, so that compiler can build OTL tables even for
an empty `TTFont` object containing no "OS/2" table.
- If `openTypeOS2UnicodeRanges` and `openTypeOS2CodePageRanges` are not set in
the fontinfo.plist, fallback values are calculated based on the font's Unicode
cmap coverage following the same algorithm as FontForge (254).
- PreProcessor now stores the cu2qu "quadratic" curve type (when running inplace),
and check its presence to avoid re-running the cubic to quadratic conversion on
a font that already has the required curve type.
- The `PostProcessor` class now also supports the Glyphs.app-specific UFO lib key
"Don't use Production Names" as an alternative method to disable renaming
glyphs to production names. The recommended method is to set the ufo2ft's own
lib key: "com.github.googlei18n.ufo2ft.useProductionNames" (True by default).
Bugfixes
- Make builds reproducible by using `calendar.timegm` to convert UTC time tuple
to Unix timestamp, and `time.gmtime` to get seconds since epoch in UTC.
Datetimes in UFO must be interpreted as UTC, not local time
(unified-font-object/ufo-spec54, 219, 221).
- Don't fail with negative advances that will be rounded to 0 (222,
googlei18n/fontmake400).
- Don't set CID-only `FontName` operator in CFF TopDict (234).
- Don't fail if all glyphs have zero advance width (249).
- Disallow multiple glyphs mapping to the same unicode codepoint. We now take
the first glyph found in the glyph order, and print a warning if duplicates
are found with the same unicode value (213).
- Use `hhea.ascender` instead of the glyph's height as fallback for the
`verticalOrigin` (233, 231).
Updated minimum requirements
- fonttools >= 3.27.1
- defcon >= 0.4.0
- cu2qu >= 1.5.0
- booleanOperations >= 0.8.0