[subset] Wire up subset() call down to subtables

src/hb-ot-layout-common.hh

@@ -702,6 +702,42 @@ struct Lookup
     return_trace (true);
   }
 
+  template <typename TSubTable>
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    struct Lookup *out = c->serializer->embed (*this);
+    if (unlikely (!out)) return_trace (false);
+
+    /* Subset the actual subtables. */
+    /* TODO Drop empty ones, either by calling intersects() beforehand,
+     * or just dropping null offsets after. */
+    const OffsetArrayOf<TSubTable>& subtables = get_subtables<TSubTable> ();
+    OffsetArrayOf<TSubTable>& out_subtables = out->get_subtables<TSubTable> ();
+    unsigned int count = subTable.len;
+    for (unsigned int i = 0; i < count; i++)
+    {
+      struct Wrapper
+      {
+        inline Wrapper (const TSubTable &subtable_,
+			unsigned int lookup_type_) :
+			  subtable (subtable_),
+			  lookup_type (lookup_type_) {}
+
+	inline bool subset (hb_subset_context_t *c) const
+	{ return subtable.dispatch (c, lookup_type); }
+
+	private:
+	const TSubTable &subtable;
+	unsigned int lookup_type;
+      } wrapper (this+subtables[i], get_type ());
+
+      out_subtables[i].serialize_subset (c, wrapper, out);
+    }
+
+    return_trace (true);
+  }
+
   template <typename TSubTable>
   inline bool sanitize (hb_sanitize_context_t *c) const
   {

src/hb-ot-layout-gpos-table.hh

@@ -484,6 +484,13 @@ struct SinglePosFormat1
     return_trace (true);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -537,6 +544,13 @@ struct SinglePosFormat2
     return_trace (true);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -742,6 +756,13 @@ struct PairPosFormat1
     return_trace ((this+pairSet[index]).apply (c, valueFormat, skippy_iter.idx));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -828,6 +849,13 @@ struct PairPosFormat2
     return_trace (true);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -1040,6 +1068,13 @@ struct CursivePosFormat1
     return_trace (true);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -1140,6 +1175,13 @@ struct MarkBasePosFormat1
     return_trace ((this+markArray).apply (c, mark_index, base_index, this+baseArray, classCount, skippy_iter.idx));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -1259,6 +1301,13 @@ struct MarkLigPosFormat1
     return_trace ((this+markArray).apply (c, mark_index, comp_index, lig_attach, classCount, j));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -1375,6 +1424,13 @@ struct MarkMarkPosFormat1
     return_trace ((this+mark1Array).apply (c, mark1_index, mark2_index, this+mark2Array, classCount, j));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -1543,6 +1599,9 @@ struct PosLookup : Lookup
   inline typename context_t::return_t dispatch (context_t *c) const
   { return Lookup::dispatch<SubTable> (c); }
 
+  inline bool subset (hb_subset_context_t *c) const
+  { return Lookup::subset<SubTable> (c); }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   { return Lookup::sanitize<SubTable> (c); }
 };
@@ -1563,11 +1622,11 @@ struct GPOS : GSUBGPOS
   static inline void position_finish_advances (hb_font_t *font, hb_buffer_t *buffer);
   static inline void position_finish_offsets (hb_font_t *font, hb_buffer_t *buffer);
 
+  inline bool subset (hb_subset_context_t *c) const
+  { return GSUBGPOS::subset<PosLookup> (c); }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
-  {
-    TRACE_SANITIZE (this);
-    return_trace (GSUBGPOS::sanitize<PosLookup> (c));
-  }
+  { return GSUBGPOS::sanitize<PosLookup> (c); }
 
   typedef GSUBGPOS::accelerator_t<GPOS> accelerator_t;
 };

src/hb-ot-layout-gsub-table.hh

@@ -102,6 +102,13 @@ struct SingleSubstFormat1
     return_trace (true);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -184,6 +191,13 @@ struct SingleSubstFormat2
     return_trace (true);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -387,6 +401,13 @@ struct MultipleSubstFormat1
     return_trace (true);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -570,6 +591,13 @@ struct AlternateSubstFormat1
     return_trace (true);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -911,6 +939,13 @@ struct LigatureSubstFormat1
     return_trace (true);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -1101,6 +1136,13 @@ struct ReverseChainSingleSubstFormat1
     return_trace (false);
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -1367,7 +1409,7 @@ struct SubstLookup : Lookup
   { return Lookup::dispatch<SubTable> (c); }
 
   inline bool subset (hb_subset_context_t *c) const
-  { return false; }//XXX Lookup::subset<SubTable> (c); }
+  { return Lookup::subset<SubTable> (c); }
 
   inline bool sanitize (hb_sanitize_context_t *c) const
   { return Lookup::sanitize<SubTable> (c); }
@@ -1386,16 +1428,10 @@ struct GSUB : GSUBGPOS
   { return CastR<SubstLookup> (GSUBGPOS::get_lookup (i)); }
 
   inline bool subset (hb_subset_context_t *c) const
-  {
-    TRACE_SUBSET (this);
-    return_trace (GSUBGPOS::subset<SubstLookup> (c));
-  }
+  { return GSUBGPOS::subset<SubstLookup> (c); }
 
   inline bool sanitize (hb_sanitize_context_t *c) const
-  {
-    TRACE_SANITIZE (this);
-    return_trace (GSUBGPOS::sanitize<SubstLookup> (c));
-  }
+  { return GSUBGPOS::sanitize<SubstLookup> (c); }
 
   typedef GSUBGPOS::accelerator_t<GSUB> accelerator_t;
 };

src/hb-ot-layout-gsubgpos.hh

@@ -1435,6 +1435,13 @@ struct ContextFormat1
     return_trace (rule_set.apply (c, lookup_context));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -1547,6 +1554,13 @@ struct ContextFormat2
     return_trace (rule_set.apply (c, lookup_context));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -1648,6 +1662,13 @@ struct ContextFormat3
     return_trace (context_apply_lookup (c, glyphCount, (const HBUINT16 *) (coverageZ + 1), lookupCount, lookupRecord, lookup_context));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -2076,6 +2097,13 @@ struct ChainContextFormat1
     return_trace (rule_set.apply (c, lookup_context));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -2209,6 +2237,13 @@ struct ChainContextFormat2
     return_trace (rule_set.apply (c, lookup_context));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -2352,6 +2387,13 @@ struct ChainContextFormat3
 					      lookup.len, lookup.arrayZ, lookup_context));
   }
 
+  inline bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    // TODO(subset)
+    return_trace (false);
+  }
+
   inline bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);