From 1ce4f2bd963578438849d45e3bdc0db38747a5c9 Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Sat, 11 May 2024 08:51:03 -0600
Subject: [PATCH] .

---
 src/hb-cff-interp-common.hh |  2 ++
 src/hb-subset-cff2.cc       | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/src/hb-cff-interp-common.hh b/src/hb-cff-interp-common.hh
index b0491385f..a3daef40e 100644
--- a/src/hb-cff-interp-common.hh
+++ b/src/hb-cff-interp-common.hh
@@ -589,6 +589,8 @@ struct interp_env_t
 		str_ref;
   arg_stack_t<ARG>
 		argStack;
+
+  using ELEM = ARG;
 };
 
 using num_interp_env_t =  interp_env_t<>;
diff --git a/src/hb-subset-cff2.cc b/src/hb-subset-cff2.cc
index eb5cb0c62..b040fb641 100644
--- a/src/hb-subset-cff2.cc
+++ b/src/hb-subset-cff2.cc
@@ -290,6 +290,19 @@ struct cff2_private_blend_encoder_param_t
 
 struct cff2_private_dict_blend_opset_t : dict_opset_t
 {
+  static void process_arg_blend (cff2_private_blend_encoder_param_t& param,
+				 number_t &arg,
+				 const hb_array_t<const number_t> blends,
+				 unsigned n, unsigned i)
+  {
+    if (env.have_coords ())
+      arg.set_int (round (arg.to_real () + env.blend_deltas (blends)));
+    else
+      arg.set_blends (n, i, blends);
+  }
+
+  template <typename T = ELEM,
+	    hb_enable_if (!hb_is_same (T, blend_arg_t))>
   static void process_arg_blend (cff2_private_blend_encoder_param_t& param,
 				 number_t &arg,
 				 const hb_array_t<const number_t> blends,
@@ -447,6 +460,12 @@ struct cff2_subset_plan
 
     if (desubroutinize)
     {
+      /* Partial instancing */
+      if (plan->normalized_coords && !plan->all_axes_pinned)
+      {
+        
+      }
+
       /* Flatten global & local subrs */
       subr_flattener_t<const OT::cff2::accelerator_subset_t, cff2_cs_interp_env_t<blend_arg_t>, cff2_cs_opset_flatten_t>
 		    flattener(acc, plan);