[subset] retian nameids from STAT and fvar tables

src/hb-ot-stat-table.hh

@@ -65,6 +65,8 @@ struct AxisValueFormat1
     return_trace (likely (c->check_struct (this)));
   }
 
+  hb_ot_name_id_t get_value_name_id () const { return valueNameID; }
+
   protected:
   HBUINT16	format;		/* Format identifier — set to 1. */
   HBUINT16	axisIndex;	/* Zero-base index into the axis record array
@@ -88,6 +90,8 @@ struct AxisValueFormat2
     return_trace (likely (c->check_struct (this)));
   }
 
+  hb_ot_name_id_t get_value_name_id () const { return valueNameID; }
+
   protected:
   HBUINT16	format;		/* Format identifier — set to 2. */
   HBUINT16	axisIndex;	/* Zero-base index into the axis record array
@@ -115,6 +119,8 @@ struct AxisValueFormat3
     return_trace (likely (c->check_struct (this)));
   }
 
+  hb_ot_name_id_t get_value_name_id () const { return valueNameID; }
+
   protected:
   HBUINT16	format;		/* Format identifier — set to 3. */
   HBUINT16	axisIndex;	/* Zero-base index into the axis record array
@@ -157,6 +163,8 @@ struct AxisValueFormat4
     return_trace (likely (c->check_struct (this)));
   }
 
+  hb_ot_name_id_t get_value_name_id () const { return valueNameID; }
+
   protected:
   HBUINT16	format;		/* Format identifier — set to 4. */
   HBUINT16	axisCount;	/* The total number of axes contributing to
@@ -191,6 +199,18 @@ struct AxisValue
     }
   }
 
+  hb_ot_name_id_t get_value_name_id () const
+  {
+    switch (u.format)
+    {
+      case 1: return u.format1.get_value_name_id ();
+      case 2: return u.format2.get_value_name_id ();
+      case 3: return u.format3.get_value_name_id ();
+      case 4: return u.format4.get_value_name_id ();
+      default: return HB_OT_NAME_ID_INVALID;
+    }
+  }
+
   protected:
   union
   {
@@ -212,6 +232,8 @@ struct StatAxisRecord
     return_trace (likely (c->check_struct (this)));
   }
 
+  hb_ot_name_id_t get_name_id () const { return nameID; }
+
   protected:
   Tag		tag;		/* A tag identifying the axis of design variation. */
   NameID	nameID;		/* The name ID for entries in the 'name' table that
@@ -231,17 +253,59 @@ struct STAT
   {
     TRACE_SANITIZE (this);
     return_trace (likely (c->check_struct (this) &&
-			  majorVersion == 1 &&
-			  minorVersion > 0 &&
+			  version.major == 1 &&
+                          version.minor > 0 &&
 			  designAxesOffset.sanitize (c, this, designAxisCount) &&
 			  offsetToAxisValueOffsets.sanitize (c, this, axisValueCount, &(this+offsetToAxisValueOffsets))));
   }
+  
+  bool has_data () const { return version.to_int (); }
+
+  unsigned get_design_axis_count () const { return designAxisCount; }
+
+  hb_ot_name_id_t get_axis_record_name_id (unsigned axis_record_index) const
+  {
+    if (unlikely (axis_record_index >= designAxisCount)) return HB_OT_NAME_ID_INVALID;
+    const StatAxisRecord &axis_record = get_design_axes ()[axis_record_index];
+    return axis_record.get_name_id ();
+  }
+
+  unsigned get_axis_value_count () const { return axisValueCount; }
+
+  hb_ot_name_id_t get_axis_value_name_id (unsigned axis_value_index) const
+  {
+    if (unlikely (axis_value_index >= axisValueCount)) return HB_OT_NAME_ID_INVALID;
+    const AxisValue &axis_value = (this + get_axis_value_offsets ()[axis_value_index]);
+    return axis_value.get_value_name_id ();
+  }
+
+  void collect_name_ids (hb_set_t *nameids_to_retain) const
+  {
+    if (!has_data ()) return;
+
+    + get_design_axes ()
+    | hb_map (&StatAxisRecord::get_name_id)
+    | hb_sink (nameids_to_retain)
+    ;
+
+    + get_axis_value_offsets ()
+    | hb_map ([&] (const OffsetTo<AxisValue>& _) -> const AxisValue* { return hb_addressof (this + _); })
+    | hb_map (&AxisValue::get_value_name_id)
+    | hb_sink (nameids_to_retain)
+    ;
+  }
 
   protected:
-  HBUINT16	majorVersion;	/* Major version number of the style attributes
-				 * table — set to 1. */
-  HBUINT16	minorVersion;	/* Minor version number of the style attributes
-				 * table — set to 2. */
+  hb_array_t<const StatAxisRecord> const get_design_axes () const
+  { return (this+designAxesOffset).as_array (designAxisCount); }
+
+  hb_array_t<const OffsetTo<AxisValue>> const get_axis_value_offsets () const
+  { return (this+offsetToAxisValueOffsets).as_array (axisValueCount); }
+
+
+  protected:
+  FixedVersion<>version;        /* Version of the stat table
+                                 * initially set to 0x00010002u */
   HBUINT16	designAxisSize;	/* The size in bytes of each axis record. */
   HBUINT16	designAxisCount;/* The number of design axis records. In a
 				 * font with an 'fvar' table, this value must be

src/hb-ot-var-fvar-table.hh

@@ -280,6 +280,27 @@ struct fvar
     return axisCount;
   }
 
+  void collect_name_ids (hb_set_t *nameids) const
+  {
+    if (!has_data ()) return;
+
+    + get_axes ()
+    | hb_map (&AxisRecord::axisNameID)
+    | hb_sink (nameids)
+    ;
+
+    + hb_range ((unsigned) instanceCount)
+    | hb_map ([&] (const unsigned _) -> unsigned { return get_instance_subfamily_name_id (_); })
+    | hb_sink (nameids)
+    ;
+
+    + hb_range ((unsigned) instanceCount)
+    | hb_map ([&] (const unsigned _) -> unsigned { return get_instance_postscript_name_id (_); })
+    | hb_sink (nameids)
+    ;
+  }
+
+
   protected:
   hb_array_t<const AxisRecord> get_axes () const
   { return hb_array (&(this+firstAxis), axisCount); }

src/hb-subset-plan.cc

@@ -31,6 +31,8 @@
 #include "hb-ot-cmap-table.hh"
 #include "hb-ot-glyf-table.hh"
 #include "hb-ot-cff1-table.hh"
+#include "hb-ot-var-fvar-table.hh"
+#include "hb-ot-stat-table.hh"
 
 static inline void
 _add_gid_and_children (const OT::glyf::accelerator_t &glyf,
@@ -192,6 +194,29 @@ _create_old_gid_to_new_gid_map (const hb_face_t *face,
   ;
 }
 
+static void
+_nameid_closure (hb_face_t           *face,
+                 hb_set_t            *nameids)
+{
+  hb_tag_t table_tags[32];
+  unsigned count = ARRAY_LENGTH (table_tags);
+  hb_face_get_table_tags (face, 0, &count, table_tags);
+  for (unsigned int i = 0; i < count; i++)
+  {
+    hb_tag_t tag = table_tags[i];
+    switch (tag) {
+      case HB_OT_TAG_STAT:
+        face->table.STAT->collect_name_ids (nameids);
+        break;
+      case HB_OT_TAG_fvar:
+        face->table.fvar->collect_name_ids (nameids);
+        break;
+      default:
+        break;
+    }
+  }
+}
+
 /**
  * hb_subset_plan_create:
  * Computes a plan for subsetting the supplied face according
@@ -217,6 +242,7 @@ hb_subset_plan_create (hb_face_t           *face,
   /* TODO Clean this up... */
   if (hb_set_is_empty (plan->name_ids))
     hb_set_add_range (plan->name_ids, 0, 0x7FFF);
+  _nameid_closure (face, plan->name_ids);
   plan->source = hb_face_reference (face);
   plan->dest = hb_face_builder_create ();
   plan->codepoint_to_glyph = hb_map_create ();