text: /*
   * Copyright © 2009  Red Hat, Inc.
   * Copyright © 2009  Keith Stribley
   * Copyright © 2015  Google, Inc.
   *
   *  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.
   *
   * Red Hat Author(s): Behdad Esfahbod
   * Google Author(s): Behdad Esfahbod
   */
  
  #include "hb.hh"
  
  #ifdef HAVE_FREETYPE
  
  #include "hb-ft.h"
  
  #include "hb-font.hh"
  #include "hb-machinery.hh"
  #include "hb-cache.hh"
  
  #include FT_ADVANCES_H
  #include FT_MULTIPLE_MASTERS_H
  #include FT_TRUETYPE_TABLES_H
  
  
  /**
   * SECTION:hb-ft
   * @title: hb-ft
   * @short_description: FreeType integration
   * @include: hb-ft.h
   *
   * Functions for using HarfBuzz with the FreeType library to provide face and
   * font data.
   **/
  
  
  /* TODO:
   *
   * In general, this file does a fine job of what it's supposed to do.
   * There are, however, things that need more work:
   *
   *   - FreeType works in 26.6 mode.  Clients can decide to use that mode, and everything
   *     would work fine.  However, we also abuse this API for performing in font-space,
   *     but don't pass the correct flags to FreeType.  We just abuse the no-hinting mode
   *     for that, such that no rounding etc happens.  As such, we don't set ppem, and
   *     pass NO_HINTING as load_flags.  Would be much better to use NO_SCALE, and scale
   *     ourselves.
   *
   *   - We don't handle / allow for emboldening / obliqueing.
   *
   *   - In the future, we should add constructors to create fonts in font space?
   */
  
  
  struct hb_ft_font_t
  {
    mutable hb_mutex_t lock;
    FT_Face ft_face;
    int load_flags;
    bool symbol; /* Whether selected cmap is symbol cmap. */
    bool unref; /* Whether to destroy ft_face when done. */
  
    mutable hb_atomic_int_t cached_x_scale;
    mutable hb_advance_cache_t advance_cache;
  };
  
  static hb_ft_font_t *
  _hb_ft_font_create (FT_Face ft_face, bool symbol, bool unref)
  {
    hb_ft_font_t *ft_font = (hb_ft_font_t *) calloc (1, sizeof (hb_ft_font_t));
  
    if (unlikely (!ft_font))
      return nullptr;
  
    ft_font->lock.init ();
    ft_font->ft_face = ft_face;
    ft_font->symbol = symbol;
    ft_font->unref = unref;
  
    ft_font->load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING;
  
    ft_font->cached_x_scale.set_relaxed (0);
    ft_font->advance_cache.init ();
  
    return ft_font;
  }
  
  static void
  _hb_ft_face_destroy (void *data)
  {
    FT_Done_Face ((FT_Face) data);
  }
  
  static void
  _hb_ft_font_destroy (void *data)
  {
    hb_ft_font_t *ft_font = (hb_ft_font_t *) data;
  
    ft_font->advance_cache.fini ();
  
    if (ft_font->unref)
      _hb_ft_face_destroy (ft_font->ft_face);
  
    ft_font->lock.fini ();
  
    free (ft_font);
  }
  
  /**
   * hb_ft_font_set_load_flags:
   * @font:
   * @load_flags:
   *
   *
   *
   * Since: 1.0.5
   **/
  void
  hb_ft_font_set_load_flags (hb_font_t *font, int load_flags)
  {
    if (hb_object_is_immutable (font))
      return;
  
    if (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)
      return;
  
    hb_ft_font_t *ft_font = (hb_ft_font_t *) font->user_data;
  
    ft_font->load_flags = load_flags;
  }
  
  /**
   * hb_ft_font_get_load_flags:
   * @font:
   *
   *
   *
   * Return value:
   * Since: 1.0.5
   **/
  int
  hb_ft_font_get_load_flags (hb_font_t *font)
  {
    if (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)
      return 0;
  
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data;
  
    return ft_font->load_flags;
  }
  
  FT_Face
  hb_ft_font_get_face (hb_font_t *font)
  {
    if (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)
      return nullptr;
  
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data;
  
    return ft_font->ft_face;
  }
  
  
  
  static hb_bool_t
  hb_ft_get_nominal_glyph (hb_font_t *font HB_UNUSED,
  			 void *font_data,
  			 hb_codepoint_t unicode,
  			 hb_codepoint_t *glyph,
  			 void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    unsigned int g = FT_Get_Char_Index (ft_font->ft_face, unicode);
  
    if (unlikely (!g))
    {
      if (unlikely (ft_font->symbol) && unicode <= 0x00FFu)
      {
        /* For symbol-encoded OpenType fonts, we duplicate the
         * U+F000..F0FF range at U+0000..U+00FF.  That's what
         * Windows seems to do, and that's hinted about at:
         * https://docs.microsoft.com/en-us/typography/opentype/spec/recom
         * under "Non-Standard (Symbol) Fonts". */
        g = FT_Get_Char_Index (ft_font->ft_face, 0xF000u + unicode);
        if (!g)
  	return false;
      }
      else
        return false;
    }
  
    *glyph = g;
    return true;
  }
  
  static unsigned int
  hb_ft_get_nominal_glyphs (hb_font_t *font HB_UNUSED,
  			  void *font_data,
  			  unsigned int count,
  			  const hb_codepoint_t *first_unicode,
  			  unsigned int unicode_stride,
  			  hb_codepoint_t *first_glyph,
  			  unsigned int glyph_stride,
  			  void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    unsigned int done;
    for (done = 0;
         done < count && (*first_glyph = FT_Get_Char_Index (ft_font->ft_face, *first_unicode));
         done++)
    {
      first_unicode = &StructAtOffsetUnaligned<hb_codepoint_t> (first_unicode, unicode_stride);
      first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);
    }
    /* We don't need to do ft_font->symbol dance here, since HB calls the singular
     * nominal_glyph() for what we don't handle here. */
    return done;
  }
  
  
  static hb_bool_t
  hb_ft_get_variation_glyph (hb_font_t *font HB_UNUSED,
  			   void *font_data,
  			   hb_codepoint_t unicode,
  			   hb_codepoint_t variation_selector,
  			   hb_codepoint_t *glyph,
  			   void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    unsigned int g = FT_Face_GetCharVariantIndex (ft_font->ft_face, unicode, variation_selector);
  
    if (unlikely (!g))
      return false;
  
    *glyph = g;
    return true;
  }
  
  static void
  hb_ft_get_glyph_h_advances (hb_font_t* font, void* font_data,
  			    unsigned count,
  			    const hb_codepoint_t *first_glyph,
  			    unsigned glyph_stride,
  			    hb_position_t *first_advance,
  			    unsigned advance_stride,
  			    void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    FT_Face ft_face = ft_font->ft_face;
    int load_flags = ft_font->load_flags;
    int mult = font->x_scale < 0 ? -1 : +1;
  
    if (font->x_scale != ft_font->cached_x_scale.get ())
    {
      ft_font->advance_cache.clear ();
      ft_font->cached_x_scale.set (font->x_scale);
    }
  
    for (unsigned int i = 0; i < count; i++)
    {
      FT_Fixed v = 0;
      hb_codepoint_t glyph = *first_glyph;
  
      unsigned int cv;
      if (ft_font->advance_cache.get (glyph, &cv))
        v = cv;
      else
      {
        FT_Get_Advance (ft_face, glyph, load_flags, &v);
        ft_font->advance_cache.set (glyph, v);
      }
  
      *first_advance = (v * mult + (1<<9)) >> 10;
      first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);
      first_advance = &StructAtOffsetUnaligned<hb_position_t> (first_advance, advance_stride);
    }
  }
  
  static hb_position_t
  hb_ft_get_glyph_v_advance (hb_font_t *font,
  			   void *font_data,
  			   hb_codepoint_t glyph,
  			   void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    FT_Fixed v;
  
    if (unlikely (FT_Get_Advance (ft_font->ft_face, glyph, ft_font->load_flags | FT_LOAD_VERTICAL_LAYOUT, &v)))
      return 0;
  
    if (font->y_scale < 0)
      v = -v;
  
    /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
     * have a Y growing upward.  Hence the extra negation. */
    return (-v + (1<<9)) >> 10;
  }
  
  static hb_bool_t
  hb_ft_get_glyph_v_origin (hb_font_t *font,
  			  void *font_data,
  			  hb_codepoint_t glyph,
  			  hb_position_t *x,
  			  hb_position_t *y,
  			  void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    FT_Face ft_face = ft_font->ft_face;
  
    if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags)))
      return false;
  
    /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
     * have a Y growing upward.  Hence the extra negation. */
    *x = ft_face->glyph->metrics.horiBearingX -   ft_face->glyph->metrics.vertBearingX;
    *y = ft_face->glyph->metrics.horiBearingY - (-ft_face->glyph->metrics.vertBearingY);
  
    if (font->x_scale < 0)
      *x = -*x;
    if (font->y_scale < 0)
      *y = -*y;
  
    return true;
  }
  
  #ifndef HB_NO_OT_SHAPE_FALLBACK
  static hb_position_t
  hb_ft_get_glyph_h_kerning (hb_font_t *font,
  			   void *font_data,
  			   hb_codepoint_t left_glyph,
  			   hb_codepoint_t right_glyph,
  			   void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    FT_Vector kerningv;
  
    FT_Kerning_Mode mode = font->x_ppem ? FT_KERNING_DEFAULT : FT_KERNING_UNFITTED;
    if (FT_Get_Kerning (ft_font->ft_face, left_glyph, right_glyph, mode, &kerningv))
      return 0;
  
    return kerningv.x;
  }
  #endif
  
  static hb_bool_t
  hb_ft_get_glyph_extents (hb_font_t *font,
  			 void *font_data,
  			 hb_codepoint_t glyph,
  			 hb_glyph_extents_t *extents,
  			 void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    FT_Face ft_face = ft_font->ft_face;
  
    if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags)))
      return false;
  
    extents->x_bearing = ft_face->glyph->metrics.horiBearingX;
    extents->y_bearing = ft_face->glyph->metrics.horiBearingY;
    extents->width = ft_face->glyph->metrics.width;
    extents->height = -ft_face->glyph->metrics.height;
    if (font->x_scale < 0)
    {
      extents->x_bearing = -extents->x_bearing;
      extents->width = -extents->width;
    }
    if (font->y_scale < 0)
    {
      extents->y_bearing = -extents->y_bearing;
      extents->height = -extents->height;
    }
    return true;
  }
  
  static hb_bool_t
  hb_ft_get_glyph_contour_point (hb_font_t *font HB_UNUSED,
  			       void *font_data,
  			       hb_codepoint_t glyph,
  			       unsigned int point_index,
  			       hb_position_t *x,
  			       hb_position_t *y,
  			       void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    FT_Face ft_face = ft_font->ft_face;
  
    if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags)))
        return false;
  
    if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE))
        return false;
  
    if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points))
        return false;
  
    *x = ft_face->glyph->outline.points[point_index].x;
    *y = ft_face->glyph->outline.points[point_index].y;
  
    return true;
  }
  
  static hb_bool_t
  hb_ft_get_glyph_name (hb_font_t *font HB_UNUSED,
  		      void *font_data,
  		      hb_codepoint_t glyph,
  		      char *name, unsigned int size,
  		      void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    FT_Face ft_face = ft_font->ft_face;
  
    hb_bool_t ret = !FT_Get_Glyph_Name (ft_face, glyph, name, size);
    if (ret && (size && !*name))
      ret = false;
  
    return ret;
  }
  
  static hb_bool_t
  hb_ft_get_glyph_from_name (hb_font_t *font HB_UNUSED,
  			   void *font_data,
  			   const char *name, int len, /* -1 means nul-terminated */
  			   hb_codepoint_t *glyph,
  			   void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    FT_Face ft_face = ft_font->ft_face;
  
    if (len < 0)
      *glyph = FT_Get_Name_Index (ft_face, (FT_String *) name);
    else {
      /* Make a nul-terminated version. */
      char buf[128];
      len = hb_min (len, (int) sizeof (buf) - 1);
      strncpy (buf, name, len);
      buf[len] = '\0';
      *glyph = FT_Get_Name_Index (ft_face, buf);
    }
  
    if (*glyph == 0)
    {
      /* Check whether the given name was actually the name of glyph 0. */
      char buf[128];
      if (!FT_Get_Glyph_Name(ft_face, 0, buf, sizeof (buf)) &&
          len < 0 ? !strcmp (buf, name) : !strncmp (buf, name, len))
        return true;
    }
  
    return *glyph != 0;
  }
  
  static hb_bool_t
  hb_ft_get_font_h_extents (hb_font_t *font HB_UNUSED,
  			  void *font_data,
  			  hb_font_extents_t *metrics,
  			  void *user_data HB_UNUSED)
  {
    const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
    hb_lock_t lock (ft_font->lock);
    FT_Face ft_face = ft_font->ft_face;
    metrics->ascender = FT_MulFix(ft_face->ascender, ft_face->size->metrics.y_scale);
    metrics->descender = FT_MulFix(ft_face->descender, ft_face->size->metrics.y_scale);
    metrics->line_gap = FT_MulFix( ft_face->height, ft_face->size->metrics.y_scale ) - (metrics->ascender - metrics->descender);
    if (font->y_scale < 0)
    {
      metrics->ascender = -metrics->ascender;
      metrics->descender = -metrics->descender;
      metrics->line_gap = -metrics->line_gap;
    }
    return true;
  }
  
  #if HB_USE_ATEXIT
  static void free_static_ft_funcs ();
  #endif
  
  static struct hb_ft_font_funcs_lazy_loader_t : hb_font_funcs_lazy_loader_t<hb_ft_font_funcs_lazy_loader_t>
  {
    static hb_font_funcs_t *create ()
    {
      hb_font_funcs_t *funcs = hb_font_funcs_create ();
  
      hb_font_funcs_set_font_h_extents_func (funcs, hb_ft_get_font_h_extents, nullptr, nullptr);
      //hb_font_funcs_set_font_v_extents_func (funcs, hb_ft_get_font_v_extents, nullptr, nullptr);
      hb_font_funcs_set_nominal_glyph_func (funcs, hb_ft_get_nominal_glyph, nullptr, nullptr);
      hb_font_funcs_set_nominal_glyphs_func (funcs, hb_ft_get_nominal_glyphs, nullptr, nullptr);
      hb_font_funcs_set_variation_glyph_func (funcs, hb_ft_get_variation_glyph, nullptr, nullptr);
      hb_font_funcs_set_glyph_h_advances_func (funcs, hb_ft_get_glyph_h_advances, nullptr, nullptr);
      hb_font_funcs_set_glyph_v_advance_func (funcs, hb_ft_get_glyph_v_advance, nullptr, nullptr);
      //hb_font_funcs_set_glyph_h_origin_func (funcs, hb_ft_get_glyph_h_origin, nullptr, nullptr);
      hb_font_funcs_set_glyph_v_origin_func (funcs, hb_ft_get_glyph_v_origin, nullptr, nullptr);
  #ifndef HB_NO_OT_SHAPE_FALLBACK
      hb_font_funcs_set_glyph_h_kerning_func (funcs, hb_ft_get_glyph_h_kerning, nullptr, nullptr);
  #endif
      //hb_font_funcs_set_glyph_v_kerning_func (funcs, hb_ft_get_glyph_v_kerning, nullptr, nullptr);
      hb_font_funcs_set_glyph_extents_func (funcs, hb_ft_get_glyph_extents, nullptr, nullptr);
      hb_font_funcs_set_glyph_contour_point_func (funcs, hb_ft_get_glyph_contour_point, nullptr, nullptr);
      hb_font_funcs_set_glyph_name_func (funcs, hb_ft_get_glyph_name, nullptr, nullptr);
      hb_font_funcs_set_glyph_from_name_func (funcs, hb_ft_get_glyph_from_name, nullptr, nullptr);
  
      hb_font_funcs_make_immutable (funcs);
  
  #if HB_USE_ATEXIT
      atexit (free_static_ft_funcs);
  #endif
  
      return funcs;
    }
  } static_ft_funcs;
  
  #if HB_USE_ATEXIT
  static
  void free_static_ft_funcs ()
  {
    static_ft_funcs.free_instance ();
  }
  #endif
  
  static hb_font_funcs_t *
  _hb_ft_get_font_funcs ()
  {
    return static_ft_funcs.get_unconst ();
  }
  
  static void
  _hb_ft_font_set_funcs (hb_font_t *font, FT_Face ft_face, bool unref)
  {
    bool symbol = ft_face->charmap && ft_face->charmap->encoding == FT_ENCODING_MS_SYMBOL;
  
    hb_font_set_funcs (font,
  		     _hb_ft_get_font_funcs (),
  		     _hb_ft_font_create (ft_face, symbol, unref),
  		     _hb_ft_font_destroy);
  }
  
  
  static hb_blob_t *
  _hb_ft_reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
  {
    FT_Face ft_face = (FT_Face) user_data;
    FT_Byte *buffer;
    FT_ULong  length = 0;
    FT_Error error;
  
    /* Note: FreeType like HarfBuzz uses the NONE tag for fetching the entire blob */
  
    error = FT_Load_Sfnt_Table (ft_face, tag, 0, nullptr, &length);
    if (error)
      return nullptr;
  
    buffer = (FT_Byte *) malloc (length);
    if (!buffer)
      return nullptr;
  
    error = FT_Load_Sfnt_Table (ft_face, tag, 0, buffer, &length);
    if (error)
    {
      free (buffer);
      return nullptr;
    }
  
    return hb_blob_create ((const char *) buffer, length,
  			 HB_MEMORY_MODE_WRITABLE,
  			 buffer, free);
  }
  
  /**
   * hb_ft_face_create:
   * @ft_face: (destroy destroy) (scope notified):
   * @destroy:
   *
   *
   *
   * Return value: (transfer full):
   * Since: 0.9.2
   **/
  hb_face_t *
  hb_ft_face_create (FT_Face           ft_face,
  		   hb_destroy_func_t destroy)
  {
    hb_face_t *face;
  
    if (!ft_face->stream->read) {
      hb_blob_t *blob;
  
      blob = hb_blob_create ((const char *) ft_face->stream->base,
  			   (unsigned int) ft_face->stream->size,
  			   HB_MEMORY_MODE_READONLY,
  			   ft_face, destroy);
      face = hb_face_create (blob, ft_face->face_index);
      hb_blob_destroy (blob);
    } else {
      face = hb_face_create_for_tables (_hb_ft_reference_table, ft_face, destroy);
    }
  
    hb_face_set_index (face, ft_face->face_index);
    hb_face_set_upem (face, ft_face->units_per_EM);
  
    return face;
  }
  
  /**
   * hb_ft_face_create_referenced:
   * @ft_face:
   *
   *
   *
   * Return value: (transfer full):
   * Since: 0.9.38
   **/
  hb_face_t *
  hb_ft_face_create_referenced (FT_Face ft_face)
  {
    FT_Reference_Face (ft_face);
    return hb_ft_face_create (ft_face, _hb_ft_face_destroy);
  }
  
  static void
  hb_ft_face_finalize (FT_Face ft_face)
  {
    hb_face_destroy ((hb_face_t *) ft_face->generic.data);
  }
  
  /**
   * hb_ft_face_create_cached:
   * @ft_face:
   *
   *
   *
   * Return value: (transfer full):
   * Since: 0.9.2
   **/
  hb_face_t *
  hb_ft_face_create_cached (FT_Face ft_face)
  {
    if (unlikely (!ft_face->generic.data || ft_face->generic.finalizer != (FT_Generic_Finalizer) hb_ft_face_finalize))
    {
      if (ft_face->generic.finalizer)
        ft_face->generic.finalizer (ft_face);
  
      ft_face->generic.data = hb_ft_face_create (ft_face, nullptr);
      ft_face->generic.finalizer = (FT_Generic_Finalizer) hb_ft_face_finalize;
    }
  
    return hb_face_reference ((hb_face_t *) ft_face->generic.data);
  }
  
  
  /**
   * hb_ft_font_create:
   * @ft_face: (destroy destroy) (scope notified):
   * @destroy:
   *
   *
   *
   * Return value: (transfer full):
   * Since: 0.9.2
   **/
  hb_font_t *
  hb_ft_font_create (FT_Face           ft_face,
  		   hb_destroy_func_t destroy)
  {
    hb_font_t *font;
    hb_face_t *face;
  
    face = hb_ft_face_create (ft_face, destroy);
    font = hb_font_create (face);
    hb_face_destroy (face);
    _hb_ft_font_set_funcs (font, ft_face, false);
    hb_ft_font_changed (font);
    return font;
  }
  
  void
  hb_ft_font_changed (hb_font_t *font)
  {
    if (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)
      return;
  
    hb_ft_font_t *ft_font = (hb_ft_font_t *) font->user_data;
    FT_Face ft_face = ft_font->ft_face;
  
    hb_font_set_scale (font,
  		     (int) (((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM + (1u<<15)) >> 16),
  		     (int) (((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM + (1u<<15)) >> 16));
  #if 0 /* hb-ft works in no-hinting model */
    hb_font_set_ppem (font,
  		    ft_face->size->metrics.x_ppem,
  		    ft_face->size->metrics.y_ppem);
  #endif
  
  #ifdef HAVE_FT_GET_VAR_BLEND_COORDINATES
    FT_MM_Var *mm_var = nullptr;
    if (!FT_Get_MM_Var (ft_face, &mm_var))
    {
      FT_Fixed *ft_coords = (FT_Fixed *) calloc (mm_var->num_axis, sizeof (FT_Fixed));
      int *coords = (int *) calloc (mm_var->num_axis, sizeof (int));
      if (coords && ft_coords)
      {
        if (!FT_Get_Var_Blend_Coordinates (ft_face, mm_var->num_axis, ft_coords))
        {
  	bool nonzero = false;
  
  	for (unsigned int i = 0; i < mm_var->num_axis; ++i)
  	 {
  	  coords[i] = ft_coords[i] >>= 2;
  	  nonzero = nonzero || coords[i];
  	 }
  
  	if (nonzero)
  	  hb_font_set_var_coords_normalized (font, coords, mm_var->num_axis);
  	else
  	  hb_font_set_var_coords_normalized (font, nullptr, 0);
        }
      }
      free (coords);
      free (ft_coords);
  #ifdef HAVE_FT_DONE_MM_VAR
      FT_Done_MM_Var (ft_face->glyph->library, mm_var);
  #else
      free (mm_var);
  #endif
    }
  #endif
  }
  
  /**
   * hb_ft_font_create_referenced:
   * @ft_face:
   *
   *
   *
   * Return value: (transfer full):
   * Since: 0.9.38
   **/
  hb_font_t *
  hb_ft_font_create_referenced (FT_Face ft_face)
  {
    FT_Reference_Face (ft_face);
    return hb_ft_font_create (ft_face, _hb_ft_face_destroy);
  }
  
  #if HB_USE_ATEXIT
  static void free_static_ft_library ();
  #endif
  
  static struct hb_ft_library_lazy_loader_t : hb_lazy_loader_t<hb_remove_pointer<FT_Library>,
  							     hb_ft_library_lazy_loader_t>
  {
    static FT_Library create ()
    {
      FT_Library l;
      if (FT_Init_FreeType (&l))
        return nullptr;
  
  #if HB_USE_ATEXIT
      atexit (free_static_ft_library);
  #endif
  
      return l;
    }
    static void destroy (FT_Library l)
    {
      FT_Done_FreeType (l);
    }
    static FT_Library get_null ()
    {
      return nullptr;
    }
  } static_ft_library;
  
  #if HB_USE_ATEXIT
  static
  void free_static_ft_library ()
  {
    static_ft_library.free_instance ();
  }
  #endif
  
  static FT_Library
  get_ft_library ()
  {
    return static_ft_library.get_unconst ();
  }
  
  static void
  _release_blob (FT_Face ft_face)
  {
    hb_blob_destroy ((hb_blob_t *) ft_face->generic.data);
  }
  
  void
  hb_ft_font_set_funcs (hb_font_t *font)
  {
    hb_blob_t *blob = hb_face_reference_blob (font->face);
    unsigned int blob_length;
    const char *blob_data = hb_blob_get_data (blob, &blob_length);
    if (unlikely (!blob_length))
      DEBUG_MSG (FT, font, "Font face has empty blob");
  
    FT_Face ft_face = nullptr;
    FT_Error err = FT_New_Memory_Face (get_ft_library (),
  				     (const FT_Byte *) blob_data,
  				     blob_length,
  				     hb_face_get_index (font->face),
  				     &ft_face);
  
    if (unlikely (err)) {
      hb_blob_destroy (blob);
      DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed");
      return;
    }
  
    if (FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE))
      FT_Select_Charmap (ft_face, FT_ENCODING_MS_SYMBOL);
  
    FT_Set_Char_Size (ft_face,
  		    abs (font->x_scale), abs (font->y_scale),
  		    0, 0);
  #if 0
  		    font->x_ppem * 72 * 64 / font->x_scale,
  		    font->y_ppem * 72 * 64 / font->y_scale);
  #endif
    if (font->x_scale < 0 || font->y_scale < 0)
    {
      FT_Matrix matrix = { font->x_scale < 0 ? -1 : +1, 0,
  			  0, font->y_scale < 0 ? -1 : +1};
      FT_Set_Transform (ft_face, &matrix, nullptr);
    }
  
  #ifdef HAVE_FT_SET_VAR_BLEND_COORDINATES
    unsigned int num_coords;
    const int *coords = hb_font_get_var_coords_normalized (font, &num_coords);
    if (num_coords)
    {
      FT_Fixed *ft_coords = (FT_Fixed *) calloc (num_coords, sizeof (FT_Fixed));
      if (ft_coords)
      {
        for (unsigned int i = 0; i < num_coords; i++)
  	ft_coords[i] = coords[i] << 2;
        FT_Set_Var_Blend_Coordinates (ft_face, num_coords, ft_coords);
        free (ft_coords);
      }
    }
  #endif
  
    ft_face->generic.data = blob;
    ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob;
  
    _hb_ft_font_set_funcs (font, ft_face, true);
    hb_ft_font_set_load_flags (font, FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING);
  }
  
  
  #endif
  