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diff --git a/gfx/harfbuzz/src/hb-style.cc b/gfx/harfbuzz/src/hb-style.cc
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+++ b/gfx/harfbuzz/src/hb-style.cc
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+/*
+ * Copyright © 2019  Ebrahim Byagowi
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ */
+
+#include "hb.hh"
+
+#ifndef HB_NO_STYLE
+
+#include "hb-ot-var-avar-table.hh"
+#include "hb-ot-var-fvar-table.hh"
+#include "hb-ot-stat-table.hh"
+#include "hb-ot-os2-table.hh"
+#include "hb-ot-head-table.hh"
+#include "hb-ot-post-table.hh"
+#include "hb-ot-face.hh"
+
+/**
+ * SECTION:hb-style
+ * @title: hb-style
+ * @short_description: Font Styles
+ * @include: hb.h
+ *
+ * Functions for fetching style information from fonts.
+ **/
+
+static inline float
+_hb_angle_to_ratio (float a)
+{
+  return tanf (a * float (-M_PI / 180.));
+}
+
+static inline float
+_hb_ratio_to_angle (float r)
+{
+  return atanf (r) * float (-180. / M_PI);
+}
+
+/**
+ * hb_style_get_value:
+ * @font: a #hb_font_t object.
+ * @style_tag: a style tag.
+ *
+ * Searches variation axes of a #hb_font_t object for a specific axis first,
+ * if not set, then tries to get default style values from different
+ * tables of the font.
+ *
+ * Returns: Corresponding axis or default value to a style tag.
+ *
+ * Since: 3.0.0
+ **/
+float
+hb_style_get_value (hb_font_t *font, hb_style_tag_t style_tag)
+{
+  if (unlikely (style_tag == HB_STYLE_TAG_SLANT_RATIO))
+    return _hb_angle_to_ratio (hb_style_get_value (font, HB_STYLE_TAG_SLANT_ANGLE));
+
+  hb_face_t *face = font->face;
+
+#ifndef HB_NO_VAR
+  hb_ot_var_axis_info_t axis;
+  if (hb_ot_var_find_axis_info (face, style_tag, &axis))
+  {
+    if (axis.axis_index < font->num_coords) return font->design_coords[axis.axis_index];
+    /* If a face is variable, fvar's default_value is better than STAT records */
+    return axis.default_value;
+  }
+#endif
+
+  if (style_tag == HB_STYLE_TAG_OPTICAL_SIZE && font->ptem)
+    return font->ptem;
+
+  /* STAT */
+  float value;
+  if (face->table.STAT->get_value (style_tag, &value))
+    return value;
+
+  switch ((unsigned) style_tag)
+  {
+  case HB_STYLE_TAG_ITALIC:
+    return face->table.OS2->is_italic () || face->table.head->is_italic () ? 1 : 0;
+  case HB_STYLE_TAG_OPTICAL_SIZE:
+  {
+    unsigned int lower, design, upper;
+    return face->table.OS2->v5 ().get_optical_size (&lower, &upper)
+	   ? (float) (lower + upper) / 2.f
+	   : hb_ot_layout_get_size_params (face, &design, nullptr, nullptr, nullptr, nullptr)
+	   ? design / 10.f
+	   : 12.f;
+  }
+  case HB_STYLE_TAG_SLANT_ANGLE:
+  {
+    float angle = face->table.post->table->italicAngle.to_float ();
+
+    if (font->slant)
+      angle = _hb_ratio_to_angle (font->slant + _hb_angle_to_ratio (angle));
+
+    return angle;
+  }
+  case HB_STYLE_TAG_WIDTH:
+    return face->table.OS2->has_data ()
+	   ? face->table.OS2->get_width ()
+	   : (face->table.head->is_condensed () ? 75 :
+	      face->table.head->is_expanded () ? 125 :
+	      100);
+  case HB_STYLE_TAG_WEIGHT:
+    return face->table.OS2->has_data ()
+	   ? face->table.OS2->usWeightClass
+	   : (face->table.head->is_bold () ? 700 : 400);
+  default:
+    return 0;
+  }
+}
+
+#endif