[aat/morx] Implement language-specific forms

Test on Mac with, eg. $ hb-view /Library/Fonts/BigCaslon.ttf -u 107 vs $ hb-view /Library/Fonts/BigCaslon.ttf -u 107 --language pl Fixes #1373
harfbuzz · Jul 18, 2022 · 2124ad8 · 2124ad8
1 parent d8574b4
commit 2124ad8
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Showing 2 changed files with 11 additions and 2 deletions.
diff --git a/src/hb-aat-layout-morx-table.hh b/src/hb-aat-layout-morx-table.hh
@@ -980,6 +980,13 @@ struct Chain
 	  setting = HB_AAT_LAYOUT_FEATURE_SELECTOR_LOWER_CASE_SMALL_CAPS;
 	  goto retry;
 	}
+	else if (type == HB_AAT_LAYOUT_FEATURE_TYPE_LANGUAGE_TAG_TYPE && setting &&
+		 /* TODO: Rudimentary language matching. */
+		 map->face->table.ltag->get_language (setting - 1) == map->props.language)
+	{
+	  flags &= feature.disableFlags;
+	  flags |= feature.enableFlags;
+	}
       }
     }
     return flags;

diff --git a/src/hb-aat-map.hh b/src/hb-aat-map.hh
@@ -52,8 +52,9 @@ struct hb_aat_map_builder_t
   public:
 
   HB_INTERNAL hb_aat_map_builder_t (hb_face_t *face_,
-				    const hb_segment_properties_t *props_ HB_UNUSED) :
-				      face (face_) {}
+				    const hb_segment_properties_t *props_) :
+				      face (face_),
+				      props (*props_) {}
 
   HB_INTERNAL void add_feature (hb_tag_t tag, unsigned int value=1);
 
@@ -87,6 +88,7 @@ struct hb_aat_map_builder_t
 
   public:
   hb_face_t *face;
+  hb_segment_properties_t props;
 
   public:
   hb_sorted_vector_t<feature_info_t> features;