[subset/cff] Support instancing

src/hb-cff1-interp-cs.hh

@@ -38,7 +38,8 @@ typedef biased_subrs_t<CFF1Subrs>   cff1_biased_subrs_t;
 struct cff1_cs_interp_env_t : cs_interp_env_t<number_t, CFF1Subrs>
 {
   template <typename ACC>
-  cff1_cs_interp_env_t (const hb_ubytes_t &str, ACC &acc, unsigned int fd)
+  cff1_cs_interp_env_t (const hb_ubytes_t &str, ACC &acc, unsigned int fd,
+			const int *coords_=nullptr, unsigned int num_coords_=0)
     : SUPER (str, acc.globalSubrs, acc.privateDicts[fd].localSubrs)
   {
     processed_width = false;

src/hb-cff2-interp-cs.hh

@@ -169,7 +169,9 @@ struct cff2_cs_interp_env_t : cs_interp_env_t<ELEM, CFF2Subrs>
   const	 CFF2VariationStore *varStore;
   unsigned int  region_count;
   unsigned int  ivs;
+  public:
   hb_vector_t<float>  scalars;
+  protected:
   bool	  do_blend;
   bool	  seen_vsindex_;
   bool	  seen_blend;

src/hb-subset-cff-common.hh

@@ -223,6 +223,7 @@ struct flatten_param_t
 {
   str_buff_t     &flatStr;
   bool	drop_hints;
+  const hb_subset_plan_t *plan;
 };
 
 template <typename ACC, typename ENV, typename OPSET, op_code_t endchar_op=OpCode_Invalid>
@@ -250,11 +251,15 @@ struct subr_flattener_t
       unsigned int fd = acc.fdSelect->get_fd (glyph);
       if (unlikely (fd >= acc.fdCount))
 	return false;
-      ENV env (str, acc, fd);
+
+
+      ENV env (str, acc, fd,
+	       plan->normalized_coords.arrayZ, plan->normalized_coords.length);
       cs_interpreter_t<ENV, OPSET, flatten_param_t> interp (env);
       flatten_param_t  param = {
         flat_charstrings.arrayZ[i],
-        (bool) (plan->flags & HB_SUBSET_FLAGS_NO_HINTING)
+        (bool) (plan->flags & HB_SUBSET_FLAGS_NO_HINTING),
+	plan
       };
       if (unlikely (!interp.interpret (param)))
 	return false;

src/hb-subset-cff2.cc

@@ -122,8 +122,43 @@ struct cff2_cs_opset_flatten_t : cff2_cs_opset_t<cff2_cs_opset_flatten_t, flatte
     SUPER::flush_args (env, param);
   }
 
+  static double instantiate_blends (const blend_arg_t &arg, cff2_cs_interp_env_t<blend_arg_t> &env, flatten_param_t& param)
+  {
+    double v = arg.to_real ();
+
+    auto &scalars = env.scalars;
+    auto &deltas = arg.deltas;
+
+    if (scalars.length != deltas.length)
+      return v;
+
+    unsigned count = scalars.length;
+    for (unsigned i = 0; i < count; i++)
+      v += (double) scalars.arrayZ[i] * deltas.arrayZ[i].to_real ();
+
+    return v;
+  }
+
   static void flatten_blends (const blend_arg_t &arg, unsigned int i, cff2_cs_interp_env_t<blend_arg_t> &env, flatten_param_t& param)
   {
+    if (!param.plan->pinned_at_default)
+    {
+      str_encoder_t  encoder (param.flatStr);
+      for (unsigned int j = 0; j < arg.numValues; j++)
+      {
+	blend_arg_t arg1 = env.argStack[i + j];
+	if (unlikely (!((arg1.blending () && (arg.numValues == arg1.numValues) && (arg1.valueIndex == j) &&
+		(arg1.deltas.length == env.get_region_count ())))))
+	{
+	  env.set_error ();
+	  return;
+	}
+	arg1.set_real (instantiate_blends (arg1, env, param));
+	encoder.encode_num (arg1);
+      }
+      return;
+    }
+
     /* flatten the default values */
     str_encoder_t  encoder (param.flatStr);
     for (unsigned int j = 0; j < arg.numValues; j++)
@@ -240,7 +275,8 @@ struct cff2_subset_plan {
     orig_fdcount = acc.fdArray->count;
 
     drop_hints = plan->flags & HB_SUBSET_FLAGS_NO_HINTING;
-    desubroutinize = plan->flags & HB_SUBSET_FLAGS_DESUBROUTINIZE;
+    desubroutinize = plan->flags & HB_SUBSET_FLAGS_DESUBROUTINIZE ||
+		     !plan->pinned_at_default;
 
     if (desubroutinize)
     {

src/hb-subset-plan.cc

@@ -769,6 +769,7 @@ _normalize_axes_location (hb_face_t *face, hb_subset_plan_t *plan)
     return;
 
   hb_array_t<const OT::AxisRecord> axes = face->table.fvar->get_axes ();
+  plan->normalized_coords.resize (axes.length);
 
   bool has_avar = face->table.avar->has_data ();
   const OT::SegmentMaps *seg_maps = nullptr;
@@ -777,6 +778,7 @@ _normalize_axes_location (hb_face_t *face, hb_subset_plan_t *plan)
 
   bool axis_not_pinned = false;
   unsigned old_axis_idx = 0, new_axis_idx = 0;
+  unsigned int i;
   for (const auto& axis : axes)
   {
     hb_tag_t axis_tag = axis.get_axis_tag ();
@@ -798,11 +800,15 @@ _normalize_axes_location (hb_face_t *face, hb_subset_plan_t *plan)
       plan->axes_location->set (axis_tag, normalized_v);
       if (normalized_v != 0)
         plan->pinned_at_default = false;
+
+      plan->normalized_coords[i] = normalized_v;
     }
     if (has_avar)
       seg_maps = &StructAfter<OT::SegmentMaps> (*seg_maps);
 
     old_axis_idx++;
+
+    i++;
   }
   plan->all_axes_pinned = !axis_not_pinned;
 }

src/hb-subset-plan.hh

@@ -190,6 +190,7 @@ struct hb_subset_plan_t
   hb_hashmap_t<hb_tag_t, hb::unique_ptr<hb_blob_t>>* sanitized_table_cache;
   //normalized axes location map
   hb_hashmap_t<hb_tag_t, int> *axes_location;
+  hb_vector_t<int> normalized_coords;
   //user specified axes location map
   hb_hashmap_t<hb_tag_t, float> *user_axes_location;
   //retained old axis index -> new axis index mapping in fvar axis array