From eed5d5efdd37bfbf06f52b67a5dd9d170576d2ee Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Wed, 18 Jan 2023 14:13:12 -0700
Subject: [PATCH] [VarComposite] Implement RESET_UNSPECIFIED_AXES

Fixes https://github.com/harfbuzz/boring-expansion-spec/issues/79
---
 src/OT/glyf/Glyph.hh             | 6 +++++-
 src/OT/glyf/VarCompositeGlyph.hh | 2 ++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/OT/glyf/Glyph.hh b/src/OT/glyf/Glyph.hh
index 9834acefc..39a5f1e6e 100644
--- a/src/OT/glyf/Glyph.hh
+++ b/src/OT/glyf/Glyph.hh
@@ -365,7 +365,11 @@ struct Glyph
 
         comp_points.reset ();
 
-	coord_setter_t coord_setter (hb_array (font->coords, font->num_coords));
+	auto component_coords = coords;
+	if (item.is_reset_unspecified_axes ())
+	  component_coords = hb_array (font->coords, font->num_coords);
+
+	coord_setter_t coord_setter (component_coords);
 	item.set_variations (coord_setter, record_points);
 
 	if (unlikely (!glyf_accelerator.glyph_for_gid (item.get_gid ())
diff --git a/src/OT/glyf/VarCompositeGlyph.hh b/src/OT/glyf/VarCompositeGlyph.hh
index adb5c1e41..3685da791 100644
--- a/src/OT/glyf/VarCompositeGlyph.hh
+++ b/src/OT/glyf/VarCompositeGlyph.hh
@@ -29,6 +29,7 @@ struct VarCompositeGlyphRecord
     HAVE_TCENTER_Y		= 0x0800,
     GID_IS_24			= 0x1000,
     AXES_HAVE_VARIATION		= 0x2000,
+    RESET_UNSPECIFIED_AXES	= 0x4000,
   };
 
   public:
@@ -60,6 +61,7 @@ struct VarCompositeGlyphRecord
   bool has_more () const { return true; }
 
   bool is_use_my_metrics () const { return flags & USE_MY_METRICS; }
+  bool is_reset_unspecified_axes () const { return flags & RESET_UNSPECIFIED_AXES; }
 
   hb_codepoint_t get_gid () const
   {