Merge pull request #1010 from googlefonts/optimize-contextual-anchors

markFeatureWriter: Optimize contextual anchor lookups
googlefonts · Jul 31, 2024 · 280c208 · 280c208
2 parents cedaacd + 10257be
commit 280c208
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Showing 3 changed files with 302 additions and 15 deletions.
diff --git a/Lib/glyphsLib/featureWriters/markFeatureWriter.py b/Lib/glyphsLib/featureWriters/markFeatureWriter.py
@@ -230,18 +230,27 @@ def _makeFeatures(self):
                 lookup.statements.append(MarkToBasePos(glyph, [anchor]).asAST())
             lookups.append(lookup)
 
+            # Insert mark glyph names after base glyph names if not specified otherwise.
+            if "&" not in after:
+                after = after.replace("*", "* &")
+
+            # Group base glyphs by anchor
+            glyphs = {}
             for glyph, anchor in glyph_anchor_pair:
+                glyphs.setdefault(anchor.key, [anchor, []])[1].append(glyph)
+
+            for anchor, bases in glyphs.values():
+                bases = " ".join(bases)
                 marks = ast.GlyphClass(
                     self.context.markClasses[anchor.key].glyphs.keys()
                 ).asFea()
-                if "&" not in after:
-                    after = after.replace("*", "* &")
-                # Replace & with mark name if present
-                contextual = after.replace("*", f"{glyph}")
+
+                # Replace * with base glyph names
+                contextual = after.replace("*", f"[{bases}]")
+
+                # Replace & with mark glyph names
                 contextual = contextual.replace("&", f"{marks}' lookup {lookupname}")
-                lkp.statements.append(
-                    ast.Comment(f"pos {contextual}; # {glyph}/{anchor.name}")
-                )
+                lkp.statements.append(ast.Comment(f"pos {contextual}; # {anchor.name}"))
 
         lookups.extend(dispatch_lookups.values())
 

diff --git a/tests/data/ContextualAnchors.glyphs b/tests/data/ContextualAnchors.glyphs
@@ -1,5 +1,5 @@
 {
-.appVersion = "3208";
+.appVersion = "3311";
 .formatVersion = 3;
 axes = (
 {
@@ -584,6 +584,13 @@ GPOS_Context = "lookupflag UseMarrkFilteringSet [twodotshorizontalbelow]; reh-ar
 };
 },
 {
+name = "*bottom.vtwodots";
+pos = (25,-159);
+userData = {
+GPOS_Context = "lookupflag UseMarrkFilteringSet [twodotsverticalbelow]; reh-ar *";
+};
+},
+{
 name = bottom;
 pos = (25,-85);
 }
@@ -622,6 +629,13 @@ GPOS_Context = "lookupflag UseMarrkFilteringSet [twodotshorizontalbelow]; reh-ar
 };
 },
 {
+name = "*bottom.vtwodots";
+pos = (55,-259);
+userData = {
+GPOS_Context = "lookupflag UseMarrkFilteringSet [twodotsverticalbelow]; reh-ar *";
+};
+},
+{
 name = bottom;
 pos = (55,-100);
 }
@@ -660,6 +674,112 @@ GPOS_Context = "lookupflag UseMarrkFilteringSet [twodotshorizontalbelow]; reh-ar
 };
 },
 {
+name = "*bottom.vtwodots";
+pos = (105,-309);
+userData = {
+GPOS_Context = "lookupflag UseMarrkFilteringSet [twodotsverticalbelow]; reh-ar *";
+};
+},
+{
+name = bottom;
+pos = (105,-100);
+}
+);
+layerId = "BFFFD157-90D3-4B85-B99D-9A2F366F03CA";
+metricRight = "=100";
+shapes = (
+{
+closed = 1;
+nodes = (
+(200,0,l),
+(200,521,l),
+(0,321,l),
+(0,200,l),
+(-40,200,l),
+(-40,0,l)
+);
+}
+);
+width = 300;
+}
+);
+metricRight = "=0";
+},
+{
+glyphname = "behDotless-ar.init.alt";
+layers = (
+{
+anchors = (
+{
+name = "*bottom.vtwodots";
+pos = (25,-159);
+userData = {
+GPOS_Context = "lookupflag UseMarrkFilteringSet [twodotsverticalbelow]; reh-ar *";
+};
+},
+{
+name = bottom;
+pos = (25,-85);
+}
+);
+layerId = "C4872ECA-A3A9-40AB-960A-1DB2202F16DE";
+metricRight = "=20";
+shapes = (
+{
+closed = 1;
+nodes = (
+(42,0,l),
+(42,148,l),
+(2,108,l),
+(2,40,l),
+(-30,40,l),
+(-30,0,l)
+);
+}
+);
+width = 62;
+},
+{
+anchors = (
+{
+name = "*bottom.vtwodots";
+pos = (55,-259);
+userData = {
+GPOS_Context = "lookupflag UseMarrkFilteringSet [twodotsverticalbelow]; reh-ar *";
+};
+},
+{
+name = bottom;
+pos = (55,-100);
+}
+);
+layerId = "3E7589AA-8194-470F-8E2F-13C1C581BE24";
+metricRight = "=50";
+shapes = (
+{
+closed = 1;
+nodes = (
+(100,0,l),
+(100,300,l),
+(0,200,l),
+(0,100,l),
+(-90,100,l),
+(-90,0,l)
+);
+}
+);
+width = 150;
+},
+{
+anchors = (
+{
+name = "*bottom.vtwodots";
+pos = (105,-309);
+userData = {
+GPOS_Context = "lookupflag UseMarrkFilteringSet [twodotsverticalbelow]; reh-ar *";
+};
+},
+{
 name = bottom;
 pos = (105,-100);
 }
@@ -1004,6 +1124,151 @@ width = 400;
 );
 },
 {
+glyphname = "twodotsverticalbelow-ar";
+layers = (
+{
+anchors = (
+{
+name = _bottom;
+pos = (115,15);
+}
+);
+layerId = "C4872ECA-A3A9-40AB-960A-1DB2202F16DE";
+shapes = (
+{
+closed = 1;
+nodes = (
+(123,-15,o),
+(130,-8,o),
+(130,0,cs),
+(130,8,o),
+(123,15,o),
+(115,15,cs),
+(107,15,o),
+(100,8,o),
+(100,0,cs),
+(100,-8,o),
+(107,-15,o),
+(115,-15,cs)
+);
+},
+{
+closed = 1;
+nodes = (
+(123,-55,o),
+(130,-48,o),
+(130,-40,cs),
+(130,-32,o),
+(123,-25,o),
+(115,-25,cs),
+(107,-25,o),
+(100,-32,o),
+(100,-40,cs),
+(100,-48,o),
+(107,-55,o),
+(115,-55,cs)
+);
+}
+);
+width = 230;
+},
+{
+anchors = (
+{
+name = _bottom;
+pos = (150,50);
+}
+);
+layerId = "3E7589AA-8194-470F-8E2F-13C1C581BE24";
+shapes = (
+{
+closed = 1;
+nodes = (
+(178,-50,o),
+(200,-28,o),
+(200,0,cs),
+(200,28,o),
+(178,50,o),
+(150,50,cs),
+(122,50,o),
+(100,28,o),
+(100,0,cs),
+(100,-28,o),
+(122,-50,o),
+(150,-50,cs)
+);
+},
+{
+closed = 1;
+nodes = (
+(178,-170,o),
+(200,-148,o),
+(200,-120,cs),
+(200,-92,o),
+(178,-70,o),
+(150,-70,cs),
+(122,-70,o),
+(100,-92,o),
+(100,-120,cs),
+(100,-148,o),
+(122,-170,o),
+(150,-170,cs)
+);
+}
+);
+width = 300;
+},
+{
+anchors = (
+{
+name = _bottom;
+pos = (200,100);
+}
+);
+layerId = "BFFFD157-90D3-4B85-B99D-9A2F366F03CA";
+shapes = (
+{
+closed = 1;
+nodes = (
+(255,-100,o),
+(300,-55,o),
+(300,0,cs),
+(300,55,o),
+(255,100,o),
+(200,100,cs),
+(145,100,o),
+(100,55,o),
+(100,0,cs),
+(100,-55,o),
+(145,-100,o),
+(200,-100,cs)
+);
+},
+{
+closed = 1;
+nodes = (
+(255,-310,o),
+(300,-265,o),
+(300,-210,cs),
+(300,-155,o),
+(255,-110,o),
+(200,-110,cs),
+(145,-110,o),
+(100,-155,o),
+(100,-210,cs),
+(100,-265,o),
+(145,-310,o),
+(200,-310,cs)
+);
+}
+);
+width = 400;
+}
+);
+metricLeft = "=dotbelow-ar";
+metricRight = "=dotbelow-ar";
+},
+{
 glyphname = "twodotshorizontalbelow-ar";
 layers = (
 {

diff --git a/tests/feature_writers_test.py b/tests/feature_writers_test.py
@@ -27,30 +27,43 @@ def test_contextual_anchors(datadir):
                 lookup mark2base_1;
                 lookup ContextualMarkDispatch_0;
                 lookup ContextualMarkDispatch_1;
+                lookup ContextualMarkDispatch_2;
             } mark;
             """
         )
 
-        lookup = feature.statements[-2].lookup
+        lookup = feature.statements[-3].lookup
         assert str(lookup) == (
             "lookup ContextualMarkDispatch_0 {\n"
             "    lookupflag UseMarrkFilteringSet [twodotshorizontalbelow];\n"
             "    # reh-ar * behDotess-ar.medi &\n"
-            "    pos reh-ar behDotless-ar.init behDotess-ar.medi"
-            " [dotbelow-ar twodotshorizontalbelow-ar]'"
-            " lookup ContextualMark_0; # behDotless-ar.init/*bottom.twodots\n"
+            "    pos reh-ar [behDotless-ar.init] behDotess-ar.medi"
+            " [dotbelow-ar twodotsverticalbelow-ar twodotshorizontalbelow-ar]'"
+            " lookup ContextualMark_0; # *bottom.twodots\n"
             "} ContextualMarkDispatch_0;\n"
         )
 
-        lookup = feature.statements[-1].lookup
+        lookup = feature.statements[-2].lookup
         assert str(lookup) == (
             "lookup ContextualMarkDispatch_1 {\n"
+            "    lookupflag UseMarrkFilteringSet [twodotsverticalbelow];\n"
             "    # reh-ar *\n"
-            "    pos reh-ar behDotless-ar.init [dotbelow-ar twodotshorizontalbelow-ar]'"
-            " lookup ContextualMark_1; # behDotless-ar.init/*bottom\n"
+            "    pos reh-ar [behDotless-ar.init behDotless-ar.init.alt]"
+            " [dotbelow-ar twodotsverticalbelow-ar twodotshorizontalbelow-ar]'"
+            " lookup ContextualMark_1; # *bottom.vtwodots\n"
             "} ContextualMarkDispatch_1;\n"
         )
 
+        lookup = feature.statements[-1].lookup
+        assert str(lookup) == (
+            "lookup ContextualMarkDispatch_2 {\n"
+            "    # reh-ar *\n"
+            "    pos reh-ar [behDotless-ar.init] "
+            "[dotbelow-ar twodotsverticalbelow-ar twodotshorizontalbelow-ar]'"
+            " lookup ContextualMark_2; # *bottom\n"
+            "} ContextualMarkDispatch_2;\n"
+        )
+
 
 def test_ignorable_anchors(datadir):
     ufos = load_to_ufos(datadir.join("IgnorableAnchors.glyphs"))