Pass "extra" substitutions from designspace rules to classifyGlyphs (#…

…731) * Pick up "extra" substitutions from designspace rules and route them to classifyGlyphs
googlefonts · Mar 20, 2023 · fca66fe · fca66fe
1 parent 0f123a7
commit fca66fe
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Showing 24 changed files with 721 additions and 14 deletions.
diff --git a/Lib/ufo2ft/__init__.py b/Lib/ufo2ft/__init__.py
@@ -1,5 +1,6 @@
 import logging
 import os
+from collections import defaultdict
 from enum import IntEnum
 
 from fontTools import varLib
@@ -121,6 +122,7 @@ def call_postprocessor(otf, ufo, glyphSet, *, postProcessorClass, **kwargs):
         cffVersion=1,
         subroutinizer=None,
         _tables=None,
+        extraSubstitutions=None,
     ),
 }
 
@@ -271,6 +273,7 @@ def compileTTF(ufo, **kwargs):
         layerNames=None,
         colrLayerReuse=False,
         colrAutoClipBoxes=False,
+        extraSubstitutions=None,
     ),
 }
 
@@ -386,6 +389,11 @@ def compileInterpolatableTTFsFromDS(designSpaceDoc, **kwargs):
     if kwargs["notdefGlyph"] is None:
         kwargs["notdefGlyph"] = _getDefaultNotdefGlyph(designSpaceDoc)
 
+    kwargs["extraSubstitutions"] = defaultdict(set)
+    for rule in designSpaceDoc.rules:
+        for left, right in rule.subs:
+            kwargs["extraSubstitutions"][left].add(right)
+
     ttfs = compileInterpolatableTTFs(ufos, **kwargs)
 
     if kwargs["inplace"]:
@@ -407,6 +415,7 @@ def compileInterpolatableTTFsFromDS(designSpaceDoc, **kwargs):
         optimizeCFF=CFFOptimization.NONE,
         colrLayerReuse=False,
         colrAutoClipBoxes=False,
+        extraSubstitutions=None,
     ),
 }
 
@@ -451,6 +460,11 @@ def compileInterpolatableOTFsFromDS(designSpaceDoc, **kwargs):
     if kwargs["notdefGlyph"] is None:
         kwargs["notdefGlyph"] = _getDefaultNotdefGlyph(designSpaceDoc)
 
+    kwargs["extraSubstitutions"] = defaultdict(set)
+    for rule in designSpaceDoc.rules:
+        for left, right in rule.subs:
+            kwargs["extraSubstitutions"][left].add(right)
+
     otfs = []
     for source in designSpaceDoc.sources:
         otfs.append(

diff --git a/Lib/ufo2ft/featureCompiler.py b/Lib/ufo2ft/featureCompiler.py
@@ -74,7 +74,7 @@ class BaseFeatureCompiler:
     layout tables from these.
     """
 
-    def __init__(self, ufo, ttFont=None, glyphSet=None, **kwargs):
+    def __init__(self, ufo, ttFont=None, glyphSet=None, extraSubstitutions=None):
         """
         Args:
           ufo: an object representing a UFO (defcon.Font or equivalent)
@@ -84,6 +84,10 @@ def __init__(self, ufo, ttFont=None, glyphSet=None, **kwargs):
             the same glyph order as the ufo object.
           glyphSet: a (optional) dict containing pre-processed copies of
             the UFO glyphs.
+          extraSubstitutions: an optional dictionary mapping glyph names
+            to a set of other glyphs which should be considered reachable
+            from them (for example when using designspace rules to effect
+            substitutions).
         """
         self.ufo = ufo
 
@@ -103,6 +107,8 @@ def __init__(self, ufo, ttFont=None, glyphSet=None, **kwargs):
             glyphSet = ufo
         self.glyphSet = OrderedDict((gn, glyphSet[gn]) for gn in glyphOrder)
 
+        self.extraSubstitutions = extraSubstitutions
+
     def setupFeatures(self):
         """Make the features source.
 
@@ -174,6 +180,7 @@ def __init__(
         glyphSet=None,
         featureWriters=None,
         feaIncludeDir=None,
+        extraSubstitutions=None,
         **kwargs,
     ):
         """
@@ -199,8 +206,9 @@ def __init__(
             the feature file. If None, the include directory is set to the
             parent directory of the UFO, provided the UFO has a path.
         """
-        BaseFeatureCompiler.__init__(self, ufo, ttFont, glyphSet)
-
+        BaseFeatureCompiler.__init__(
+            self, ufo, ttFont, glyphSet, extraSubstitutions=extraSubstitutions
+        )
         self.feaIncludeDir = feaIncludeDir
 
         self.initFeatureWriters(featureWriters)

diff --git a/Lib/ufo2ft/featureWriters/baseFeatureWriter.py b/Lib/ufo2ft/featureWriters/baseFeatureWriter.py
@@ -330,6 +330,11 @@ def compileGSUB(self):
             compiler._gsub = gsub
         return gsub
 
+    def extraSubstitutions(self):
+        compiler = self.context.compiler
+        if compiler is not None:
+            return compiler.extraSubstitutions
+
     def getOpenTypeCategories(self):
         """Return 'public.openTypeCategories' values as a tuple of sets of
         unassigned, bases, ligatures, marks, components."""

diff --git a/Lib/ufo2ft/featureWriters/cursFeatureWriter.py b/Lib/ufo2ft/featureWriters/cursFeatureWriter.py
@@ -24,7 +24,8 @@ def _makeCursiveFeature(self):
         cmap = self.makeUnicodeToGlyphNameMapping()
         if any(unicodeScriptDirection(uv) == "LTR" for uv in cmap):
             gsub = self.compileGSUB()
-            dirGlyphs = classifyGlyphs(unicodeScriptDirection, cmap, gsub)
+            extras = self.extraSubstitutions()
+            dirGlyphs = classifyGlyphs(unicodeScriptDirection, cmap, gsub, extras)
             shouldSplit = "LTR" in dirGlyphs
         else:
             shouldSplit = False

diff --git a/Lib/ufo2ft/featureWriters/kernFeatureWriter.py b/Lib/ufo2ft/featureWriters/kernFeatureWriter.py
@@ -237,9 +237,10 @@ def setContext(self, font, feaFile, compiler=None):
         # `glyphUnicodeMapping: dict[str, int] | None` to `BaseFeatureCompiler`?
         cmap = self.makeUnicodeToGlyphNameMapping()
         gsub = self.compileGSUB()
+        extras = self.extraSubstitutions()
         ctx.knownScripts = self.guessFontScripts()
-        scriptGlyphs = classifyGlyphs(self.knownScriptsPerCodepoint, cmap, gsub)
-        bidiGlyphs = classifyGlyphs(unicodeBidiType, cmap, gsub)
+        scriptGlyphs = classifyGlyphs(self.knownScriptsPerCodepoint, cmap, gsub, extras)
+        bidiGlyphs = classifyGlyphs(unicodeBidiType, cmap, gsub, extras)
         ctx.bidiGlyphs = bidiGlyphs
 
         glyphScripts = {}

diff --git a/Lib/ufo2ft/featureWriters/kernFeatureWriter2.py b/Lib/ufo2ft/featureWriters/kernFeatureWriter2.py
@@ -321,11 +321,12 @@ def _makeKerningLookups(self):
             # type. We then mark each kerning pair with these properties when
             # any of the glyphs involved in a pair intersects these groups.
             gsub = self.compileGSUB()
-            dirGlyphs = classifyGlyphs(unicodeScriptDirection, cmap, gsub)
+            extras = self.extraSubstitutions()
+            dirGlyphs = classifyGlyphs(unicodeScriptDirection, cmap, gsub, extras)
             directions = self._intersectPairs("directions", dirGlyphs)
             shouldSplit = "RTL" in directions
             if shouldSplit:
-                bidiGlyphs = classifyGlyphs(unicodeBidiType, cmap, gsub)
+                bidiGlyphs = classifyGlyphs(unicodeBidiType, cmap, gsub, extras)
                 self._intersectPairs("bidiTypes", bidiGlyphs)
         else:
             shouldSplit = False

diff --git a/Lib/ufo2ft/featureWriters/markFeatureWriter.py b/Lib/ufo2ft/featureWriters/markFeatureWriter.py
@@ -876,7 +876,8 @@ def unicodeIsNotAbvm(uv):
                 # substitutions and get the set of all the relevant glyphs,
                 # including alternate glyphs.
                 gsub = self.compileGSUB()
-                glyphGroups = classifyGlyphs(unicodeIsAbvm, cmap, gsub)
+                extras = self.extraSubstitutions()
+                glyphGroups = classifyGlyphs(unicodeIsAbvm, cmap, gsub, extras)
                 # the 'glyphGroups' dict is keyed by the return value of the
                 # classifying include, so here 'True' means all the
                 # Indic/USE/Khmer glyphs
@@ -885,7 +886,7 @@ def unicodeIsNotAbvm(uv):
                 # If a character can be used in Indic/USE/Khmer scripts as well
                 # as other scripts, we want to return it in both 'abvmGlyphs'
                 # (done above) and 'notAbvmGlyphs' (done below) sets.
-                glyphGroups = classifyGlyphs(unicodeIsNotAbvm, cmap, gsub)
+                glyphGroups = classifyGlyphs(unicodeIsNotAbvm, cmap, gsub, extras)
                 notAbvmGlyphs = glyphGroups.get(True, set())
                 # Since cmap might not cover all glyphs, we union with the
                 # glyph set.

diff --git a/Lib/ufo2ft/util.py b/Lib/ufo2ft/util.py
@@ -284,14 +284,17 @@ def closeGlyphsOverGSUB(gsub, glyphs):
     gsub.closure_glyphs(subsetter)
 
 
-def classifyGlyphs(unicodeFunc, cmap, gsub=None):
+def classifyGlyphs(unicodeFunc, cmap, gsub=None, extra_substitutions=None):
     """'unicodeFunc' is a callable that takes a Unicode codepoint and
     returns a string, or collection of strings, denoting some Unicode
     property associated with the given character (or None if a character
     is considered 'neutral'). 'cmap' is a dictionary mapping Unicode
     codepoints to glyph names. 'gsub' is an (optional) fonttools GSUB
     table object, used to find all the glyphs that are "reachable" via
     substitutions from the initial sets of glyphs defined in the cmap.
+    'extra_substitutions' is an optional dictionary mapping glyph names
+    to a set of other glyphs which should be considered reachable from them
+    (for example when using designspace rules to effect substitutions).
 
     Returns a dictionary of glyph sets associated with the given Unicode
     properties.
@@ -317,6 +320,13 @@ def classifyGlyphs(unicodeFunc, cmap, gsub=None):
             closeGlyphsOverGSUB(gsub, s)
             glyphs.update(s - neutralGlyphs)
 
+    if extra_substitutions:
+        for glyphs in glyphSets.values():
+            to_append = set()
+            for glyph in glyphs:
+                to_append |= extra_substitutions.get(glyph, set())
+            glyphs.update(to_append)
+
     return glyphSets
 
 

diff --git a/tests/data/Alternates-Regular.ufo/features.fea b/tests/data/Alternates-Regular.ufo/features.fea
@@ -0,0 +1,6 @@
+# Prefix: Languagesystems
+languagesystem DFLT dflt;
+
+languagesystem ory2 dflt;
+languagesystem latn dflt; # This is needed in our full builds because we use feature variations
+
diff --git a/tests/data/Alternates-Regular.ufo/fontinfo.plist b/tests/data/Alternates-Regular.ufo/fontinfo.plist
@@ -0,0 +1,14 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+  <dict>
+    <key>ascender</key>
+    <integer>1069</integer>
+    <key>capHeight</key>
+    <integer>714</integer>
+    <key>descender</key>
+    <integer>-293</integer>
+    <key>familyName</key>
+    <string>Alternates</string>
+  </dict>
+</plist>
diff --git a/tests/data/Alternates-Regular.ufo/glyphs/contents.plist b/tests/data/Alternates-Regular.ufo/glyphs/contents.plist
@@ -0,0 +1,20 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+  <dict>
+    <key>ka-oriya</key>
+    <string>ka-oriya.glif</string>
+    <key>ka-oriya.BRACKET.varAlt01</key>
+    <string>ka-oriya.B_R_A_C_K_E_T_.varA_lt01.glif</string>
+    <key>ka-oriya.below</key>
+    <string>ka-oriya.below.glif</string>
+    <key>lVocalicMatra-oriya</key>
+    <string>lV_ocalicM_atra-oriya.glif</string>
+    <key>lVocalicMatra-oriya.BRACKET.varAlt01</key>
+    <string>lV_ocalicM_atra-oriya.B_R_A_C_K_E_T_.varA_lt01.glif</string>
+    <key>uuMatra-oriya</key>
+    <string>uuM_atra-oriya.glif</string>
+    <key>uuMatra-oriya.BRACKET.varAlt01</key>
+    <string>uuM_atra-oriya.B_R_A_C_K_E_T_.varA_lt01.glif</string>
+  </dict>
+</plist>
diff --git a/tests/data/Alternates-Regular.ufo/glyphs/ka-oriya.B_R_A_C_K_E_T_.varA_lt01.glif b/tests/data/Alternates-Regular.ufo/glyphs/ka-oriya.B_R_A_C_K_E_T_.varA_lt01.glif
@@ -0,0 +1,100 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<glyph name="ka-oriya.BRACKET.varAlt01" format="2">
+  <advance width="752.38889"/>
+  <note>
+kaorya
+</note>
+  <anchor x="496" y="0" name="bottom"/>
+  <anchor x="574" y="0" name="bottom_ra"/>
+  <anchor x="574" y="10" name="bottom_ta"/>
+  <anchor x="367" y="658" name="top"/>
+  <anchor x="624" y="658" name="topright"/>
+  <outline>
+    <contour>
+      <point x="152" y="201" type="curve"/>
+      <point x="152" y="201" type="line"/>
+      <point x="178" y="258" type="line"/>
+      <point x="132" y="300"/>
+      <point x="108" y="350"/>
+      <point x="108" y="403" type="curve"/>
+      <point x="108" y="520"/>
+      <point x="221" y="593"/>
+      <point x="367" y="593" type="curve"/>
+      <point x="504" y="593"/>
+      <point x="640" y="527"/>
+      <point x="640" y="395" type="curve"/>
+      <point x="640" y="351"/>
+      <point x="625" y="312"/>
+      <point x="600" y="281" type="curve"/>
+      <point x="671" y="250" type="line"/>
+      <point x="702" y="290"/>
+      <point x="720" y="339"/>
+      <point x="720" y="395" type="curve"/>
+      <point x="720" y="575"/>
+      <point x="545" y="666"/>
+      <point x="367" y="666" type="curve"/>
+      <point x="181" y="666"/>
+      <point x="32" y="566"/>
+      <point x="32" y="411" type="curve"/>
+      <point x="32" y="332"/>
+      <point x="70" y="262"/>
+    </contour>
+    <contour>
+      <point x="244" y="74" type="curve"/>
+      <point x="244" y="74" type="line"/>
+      <point x="323" y="74"/>
+      <point x="373" y="132"/>
+      <point x="373" y="215" type="curve"/>
+      <point x="373" y="297"/>
+      <point x="324" y="355"/>
+      <point x="245" y="355" type="curve"/>
+      <point x="165" y="355"/>
+      <point x="114" y="297"/>
+      <point x="114" y="213" type="curve"/>
+      <point x="114" y="131"/>
+      <point x="164" y="74"/>
+    </contour>
+    <contour>
+      <point x="245" y="135" type="curve"/>
+      <point x="245" y="135" type="line"/>
+      <point x="204" y="135"/>
+      <point x="178" y="170"/>
+      <point x="178" y="214" type="curve"/>
+      <point x="178" y="258"/>
+      <point x="204" y="293"/>
+      <point x="245" y="293" type="curve"/>
+      <point x="285" y="293"/>
+      <point x="312" y="258"/>
+      <point x="312" y="215" type="curve"/>
+      <point x="312" y="170"/>
+      <point x="286" y="135"/>
+    </contour>
+    <contour>
+      <point x="312" y="148" type="line"/>
+      <point x="304" y="0" type="line"/>
+      <point x="382" y="0" type="line"/>
+      <point x="382" y="216" type="line" smooth="yes"/>
+      <point x="382" y="265"/>
+      <point x="403" y="294"/>
+      <point x="440" y="294" type="curve"/>
+      <point x="475" y="294"/>
+      <point x="496" y="265"/>
+      <point x="496" y="216" type="curve"/>
+      <point x="496" y="0" type="line"/>
+      <point x="574" y="0" type="line"/>
+      <point x="574" y="222" type="line" smooth="yes"/>
+      <point x="574" y="305"/>
+      <point x="535" y="355"/>
+      <point x="452" y="355" type="curve"/>
+      <point x="377" y="355"/>
+      <point x="335" y="305"/>
+      <point x="335" y="222" type="curve"/>
+    </contour>
+  </outline>
+  <lib>
+    <dict>
+      <key>com.schriftgestaltung.Glyphs._originalLayerName</key>
+      <string></string>
+    </dict>
+  </lib>
+</glyph>