1 files changed, 212 insertions, 81 deletions

diff --git a/src/3rdparty/harfbuzz-ng/src/hb-ot-hmtx-table.hh b/src/3rdparty/harfbuzz-ng/src/hb-ot-hmtx-table.hh
index e710aee42e..e20b372622 100644
--- a/src/3rdparty/harfbuzz-ng/src/hb-ot-hmtx-table.hh
+++ b/src/3rdparty/harfbuzz-ng/src/hb-ot-hmtx-table.hh
@@ -21,42 +21,50 @@
  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  *
- * Google Author(s): Behdad Esfahbod
+ * Google Author(s): Behdad Esfahbod, Roderick Sheeter
  */
 
 #ifndef HB_OT_HMTX_TABLE_HH
 #define HB_OT_HMTX_TABLE_HH
 
-#include "hb-open-type-private.hh"
+#include "hb-open-type.hh"
 #include "hb-ot-hhea-table.hh"
-#include "hb-ot-os2-table.hh"
 #include "hb-ot-var-hvar-table.hh"
-
-
-namespace OT {
-
+#include "hb-ot-metrics.hh"
 
 /*
- * hmtx -- The Horizontal Metrics Table
- * vmtx -- The Vertical Metrics Table
+ * hmtx -- Horizontal Metrics
+ * https://docs.microsoft.com/en-us/typography/opentype/spec/hmtx
+ * vmtx -- Vertical Metrics
+ * https://docs.microsoft.com/en-us/typography/opentype/spec/vmtx
  */
-
 #define HB_OT_TAG_hmtx HB_TAG('h','m','t','x')
 #define HB_OT_TAG_vmtx HB_TAG('v','m','t','x')
 
 
+HB_INTERNAL int
+_glyf_get_side_bearing_var (hb_font_t *font, hb_codepoint_t glyph, bool is_vertical);
+
+HB_INTERNAL unsigned
+_glyf_get_advance_var (hb_font_t *font, hb_codepoint_t glyph, bool is_vertical);
+
+
+namespace OT {
+
+
 struct LongMetric
 {
   UFWORD	advance; /* Advance width/height. */
-  FWORD		lsb; /* Leading (left/top) side bearing. */
+  FWORD		sb; /* Leading (left/top) side bearing. */
   public:
   DEFINE_SIZE_STATIC (4);
 };
 
-template <typename T>
+
+template <typename T, typename H>
 struct hmtxvmtx
 {
-  inline bool sanitize (hb_sanitize_context_t *c) const
+  bool sanitize (hb_sanitize_context_t *c HB_UNUSED) const
   {
     TRACE_SANITIZE (this);
     /* We don't check for anything specific here.  The users of the
@@ -64,47 +72,107 @@ struct hmtxvmtx
     return_trace (true);
   }
 
-  struct accelerator_t
+
+  bool subset_update_header (hb_subset_plan_t *plan,
+			     unsigned int num_hmetrics) const
   {
-    inline void init (hb_face_t *face,
-		      unsigned int default_advance_ = 0)
-    {
-      default_advance = default_advance_ ? default_advance_ : face->get_upem ();
+    hb_blob_t *src_blob = hb_sanitize_context_t ().reference_table<H> (plan->source, H::tableTag);
+    hb_blob_t *dest_blob = hb_blob_copy_writable_or_fail (src_blob);
+    hb_blob_destroy (src_blob);
 
-      bool got_font_extents = false;
-      if (T::os2Tag)
-      {
-	hb_blob_t *os2_blob = Sanitizer<os2>::sanitize (face->reference_table (T::os2Tag));
-	const os2 *os2_table = Sanitizer<os2>::lock_instance (os2_blob);
-#define USE_TYPO_METRICS (1u<<7)
-	if (0 != (os2_table->fsSelection & USE_TYPO_METRICS))
-	{
-	  ascender = os2_table->sTypoAscender;
-	  descender = os2_table->sTypoDescender;
-	  line_gap = os2_table->sTypoLineGap;
-	  got_font_extents = (ascender | descender) != 0;
-	}
-	hb_blob_destroy (os2_blob);
-      }
+    if (unlikely (!dest_blob)) {
+      return false;
+    }
 
-      hb_blob_t *_hea_blob = Sanitizer<_hea>::sanitize (face->reference_table (T::headerTag));
-      const _hea *_hea_table = Sanitizer<_hea>::lock_instance (_hea_blob);
-      num_advances = _hea_table->numberOfLongMetrics;
-      if (!got_font_extents)
-      {
-	ascender = _hea_table->ascender;
-	descender = _hea_table->descender;
-	line_gap = _hea_table->lineGap;
-	got_font_extents = (ascender | descender) != 0;
-      }
-      hb_blob_destroy (_hea_blob);
+    unsigned int length;
+    H *table = (H *) hb_blob_get_data (dest_blob, &length);
+    table->numberOfLongMetrics = num_hmetrics;
+
+    bool result = plan->add_table (H::tableTag, dest_blob);
+    hb_blob_destroy (dest_blob);
+
+    return result;
+  }
+
+  template<typename Iterator,
+	   hb_requires (hb_is_iterator (Iterator))>
+  void serialize (hb_serialize_context_t *c,
+		  Iterator it,
+		  unsigned num_advances)
+  {
+    unsigned idx = 0;
+    + it
+    | hb_apply ([c, &idx, num_advances] (const hb_item_type<Iterator>& _)
+		{
+		  if (idx < num_advances)
+		  {
+		    LongMetric lm;
+		    lm.advance = _.first;
+		    lm.sb = _.second;
+		    if (unlikely (!c->embed<LongMetric> (&lm))) return;
+		  }
+		  else
+		  {
+		    FWORD *sb = c->allocate_size<FWORD> (FWORD::static_size);
+		    if (unlikely (!sb)) return;
+		    *sb = _.second;
+		  }
+		  idx++;
+		})
+    ;
+  }
+
+  bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+
+    T *table_prime = c->serializer->start_embed <T> ();
+    if (unlikely (!table_prime)) return_trace (false);
+
+    accelerator_t _mtx;
+    _mtx.init (c->plan->source);
+    unsigned num_advances = _mtx.num_advances_for_subset (c->plan);
+
+    auto it =
+    + hb_range (c->plan->num_output_glyphs ())
+    | hb_map ([c, &_mtx] (unsigned _)
+	      {
+		hb_codepoint_t old_gid;
+		if (!c->plan->old_gid_for_new_gid (_, &old_gid))
+		  return hb_pair (0u, 0);
+		return hb_pair (_mtx.get_advance (old_gid), _mtx.get_side_bearing (old_gid));
+	      })
+    ;
+
+    table_prime->serialize (c->serializer, it, num_advances);
+
+    _mtx.fini ();
+
+    if (unlikely (c->serializer->ran_out_of_room || c->serializer->in_error ()))
+      return_trace (false);
+
+    // Amend header num hmetrics
+    if (unlikely (!subset_update_header (c->plan, num_advances)))
+      return_trace (false);
+
+    return_trace (true);
+  }
 
-      has_font_extents = got_font_extents;
+  struct accelerator_t
+  {
+    friend struct hmtxvmtx;
 
-      blob = Sanitizer<hmtxvmtx>::sanitize (face->reference_table (T::tableTag));
+    void init (hb_face_t *face,
+	       unsigned int default_advance_ = 0)
+    {
+      default_advance = default_advance_ ? default_advance_ : hb_face_get_upem (face);
+
+      num_advances = T::is_horizontal ? face->table.hhea->numberOfLongMetrics : face->table.vhea->numberOfLongMetrics;
+
+      table = hb_sanitize_context_t().reference_table<hmtxvmtx> (face, T::tableTag);
 
       /* Cap num_metrics() and num_advances() based on table length. */
-      unsigned int len = hb_blob_get_length (blob);
+      unsigned int len = table.get_length ();
       if (unlikely (num_advances * 4 > len))
 	num_advances = len / 4;
       num_metrics = num_advances + (len - 4 * num_advances) / 2;
@@ -114,23 +182,49 @@ struct hmtxvmtx
       if (unlikely (!num_advances))
       {
 	num_metrics = num_advances = 0;
-	hb_blob_destroy (blob);
-	blob = hb_blob_get_empty ();
+	table.destroy ();
+	table = hb_blob_get_empty ();
       }
-      table = Sanitizer<hmtxvmtx>::lock_instance (blob);
 
-      var_blob = Sanitizer<HVARVVAR>::sanitize (face->reference_table (T::variationsTag));
-      var_table = Sanitizer<HVARVVAR>::lock_instance (var_blob);
+      var_table = hb_sanitize_context_t().reference_table<HVARVVAR> (face, T::variationsTag);
+    }
+
+    void fini ()
+    {
+      table.destroy ();
+      var_table.destroy ();
     }
 
-    inline void fini (void)
+    int get_side_bearing (hb_codepoint_t glyph) const
     {
-      hb_blob_destroy (blob);
-      hb_blob_destroy (var_blob);
+      if (glyph < num_advances)
+	return table->longMetricZ[glyph].sb;
+
+      if (unlikely (glyph >= num_metrics))
+	return 0;
+
+      const FWORD *bearings = (const FWORD *) &table->longMetricZ[num_advances];
+      return bearings[glyph - num_advances];
+    }
+
+    int get_side_bearing (hb_font_t *font, hb_codepoint_t glyph) const
+    {
+      int side_bearing = get_side_bearing (glyph);
+
+#ifndef HB_NO_VAR
+      if (unlikely (glyph >= num_metrics) || !font->num_coords)
+	return side_bearing;
+
+      if (var_table.get_length ())
+        return side_bearing + var_table->get_side_bearing_var (glyph, font->coords, font->num_coords); // TODO Optimize?!
+
+      return _glyf_get_side_bearing_var (font, glyph, T::tableTag == HB_OT_TAG_vmtx);
+#else
+      return side_bearing;
+#endif
     }
 
-    inline unsigned int get_advance (hb_codepoint_t  glyph,
-				     hb_font_t      *font) const
+    unsigned int get_advance (hb_codepoint_t glyph) const
     {
       if (unlikely (glyph >= num_metrics))
       {
@@ -143,29 +237,65 @@ struct hmtxvmtx
 	  return default_advance;
       }
 
-      return table->longMetric[MIN (glyph, (uint32_t) num_advances - 1)].advance
-	   + var_table->get_advance_var (glyph, font->coords, font->num_coords); // TODO Optimize?!
+      return table->longMetricZ[hb_min (glyph, (uint32_t) num_advances - 1)].advance;
     }
 
-    public:
-    bool has_font_extents;
-    unsigned short ascender;
-    unsigned short descender;
-    unsigned short line_gap;
+    unsigned int get_advance (hb_codepoint_t  glyph,
+			      hb_font_t      *font) const
+    {
+      unsigned int advance = get_advance (glyph);
+
+#ifndef HB_NO_VAR
+      if (unlikely (glyph >= num_metrics) || !font->num_coords)
+	return advance;
+
+      if (var_table.get_length ())
+	return advance + roundf (var_table->get_advance_var (font, glyph)); // TODO Optimize?!
+
+      return _glyf_get_advance_var (font, glyph, T::tableTag == HB_OT_TAG_vmtx);
+#else
+      return advance;
+#endif
+    }
+
+    unsigned int num_advances_for_subset (const hb_subset_plan_t *plan) const
+    {
+      unsigned int num_advances = plan->num_output_glyphs ();
+      unsigned int last_advance = _advance_for_new_gid (plan,
+							num_advances - 1);
+      while (num_advances > 1 &&
+	     last_advance == _advance_for_new_gid (plan,
+						   num_advances - 2))
+      {
+	num_advances--;
+      }
+
+      return num_advances;
+    }
 
     private:
+    unsigned int _advance_for_new_gid (const hb_subset_plan_t *plan,
+				       hb_codepoint_t new_gid) const
+    {
+      hb_codepoint_t old_gid;
+      if (!plan->old_gid_for_new_gid (new_gid, &old_gid))
+	return 0;
+
+      return get_advance (old_gid);
+    }
+
+    protected:
     unsigned int num_metrics;
     unsigned int num_advances;
     unsigned int default_advance;
 
-    const hmtxvmtx *table;
-    hb_blob_t *blob;
-    const HVARVVAR *var_table;
-    hb_blob_t *var_blob;
+    private:
+    hb_blob_ptr_t<hmtxvmtx> table;
+    hb_blob_ptr_t<HVARVVAR> var_table;
   };
 
   protected:
-  LongMetric	longMetric[VAR];	/* Paired advance width and leading
+  UnsizedArrayOf<LongMetric>longMetricZ;/* Paired advance width and leading
 					 * bearing values for each glyph. The
 					 * value numOfHMetrics comes from
 					 * the 'hhea' table. If the font is
@@ -173,7 +303,7 @@ struct hmtxvmtx
 					 * be in the array, but that entry is
 					 * required. The last entry applies to
 					 * all subsequent glyphs. */
-  FWORD		leadingBearingX[VAR];	/* Here the advance is assumed
+/*UnsizedArrayOf<FWORD>	leadingBearingX;*//* Here the advance is assumed
 					 * to be the same as the advance
 					 * for the last entry above. The
 					 * number of entries in this array is
@@ -187,22 +317,23 @@ struct hmtxvmtx
 					 * font to vary the side bearing
 					 * values for each glyph. */
   public:
-  DEFINE_SIZE_ARRAY2 (0, longMetric, leadingBearingX);
+  DEFINE_SIZE_ARRAY (0, longMetricZ);
 };
 
-struct hmtx : hmtxvmtx<hmtx> {
-  static const hb_tag_t tableTag	= HB_OT_TAG_hmtx;
-  static const hb_tag_t headerTag	= HB_OT_TAG_hhea;
-  static const hb_tag_t variationsTag	= HB_OT_TAG_HVAR;
-  static const hb_tag_t os2Tag		= HB_OT_TAG_os2;
+struct hmtx : hmtxvmtx<hmtx, hhea> {
+  static constexpr hb_tag_t tableTag = HB_OT_TAG_hmtx;
+  static constexpr hb_tag_t variationsTag = HB_OT_TAG_HVAR;
+  static constexpr bool is_horizontal = true;
 };
-struct vmtx : hmtxvmtx<vmtx> {
-  static const hb_tag_t tableTag	= HB_OT_TAG_vmtx;
-  static const hb_tag_t headerTag	= HB_OT_TAG_vhea;
-  static const hb_tag_t variationsTag	= HB_OT_TAG_VVAR;
-  static const hb_tag_t os2Tag		= HB_TAG_NONE;
+struct vmtx : hmtxvmtx<vmtx, vhea> {
+  static constexpr hb_tag_t tableTag = HB_OT_TAG_vmtx;
+  static constexpr hb_tag_t variationsTag = HB_OT_TAG_VVAR;
+  static constexpr bool is_horizontal = false;
 };
 
+struct hmtx_accelerator_t : hmtx::accelerator_t {};
+struct vmtx_accelerator_t : vmtx::accelerator_t {};
+
 } /* namespace OT */