src/hb-aat-layout.cc

/*
 * Copyright © 2017  Google, Inc.
 * Copyright © 2018  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.
 *
 * Google Author(s): Behdad Esfahbod
 */

#include "hb-open-type.hh"

#include "hb-ot-face.hh"
#include "hb-aat.h"
#include "hb-aat-layout.hh"
#include "hb-aat-layout-ankr-table.hh"
#include "hb-aat-layout-bsln-table.hh" // Just so we compile it; unused otherwise.
#include "hb-aat-layout-feat-table.hh"
#include "hb-aat-layout-just-table.hh" // Just so we compile it; unused otherwise.
#include "hb-aat-layout-kerx-table.hh"
#include "hb-aat-layout-morx-table.hh"
#include "hb-aat-layout-trak-table.hh"
#include "hb-aat-ltag-table.hh"


/* Table data courtesy of Apple.  Converted from mnemonics to integers
 * when moving to this file. */
static const hb_aat_feature_mapping_t feature_mappings[] =
{
  {HB_TAG ('a','f','r','c'), HB_AAT_LAYOUT_FEATURE_TYPE_FRACTIONS,               HB_AAT_LAYOUT_SELECTOR_VERTICAL_FRACTIONS,             HB_AAT_LAYOUT_SELECTOR_NO_FRACTIONS},
  {HB_TAG ('c','2','p','c'), HB_AAT_LAYOUT_FEATURE_TYPE_UPPER_CASE,              HB_AAT_LAYOUT_SELECTOR_UPPER_CASE_PETITE_CAPS,         HB_AAT_LAYOUT_SELECTOR_DEFAULT_UPPER_CASE},
  {HB_TAG ('c','2','s','c'), HB_AAT_LAYOUT_FEATURE_TYPE_UPPER_CASE,              HB_AAT_LAYOUT_SELECTOR_UPPER_CASE_SMALL_CAPS,          HB_AAT_LAYOUT_SELECTOR_DEFAULT_UPPER_CASE},
  {HB_TAG ('c','a','l','t'), HB_AAT_LAYOUT_FEATURE_TYPE_CONTEXTUAL_ALTERNATIVES, HB_AAT_LAYOUT_SELECTOR_CONTEXTUAL_ALTERNATES_ON,       HB_AAT_LAYOUT_SELECTOR_CONTEXTUAL_ALTERNATES_OFF},
  {HB_TAG ('c','a','s','e'), HB_AAT_LAYOUT_FEATURE_TYPE_CASE_SENSITIVE_LAYOUT,   HB_AAT_LAYOUT_SELECTOR_CASE_SENSITIVE_LAYOUT_ON,       HB_AAT_LAYOUT_SELECTOR_CASE_SENSITIVE_LAYOUT_OFF},
  {HB_TAG ('c','l','i','g'), HB_AAT_LAYOUT_FEATURE_TYPE_LIGATURES,               HB_AAT_LAYOUT_SELECTOR_CONTEXTUAL_LIGATURES_ON,        HB_AAT_LAYOUT_SELECTOR_CONTEXTUAL_LIGATURES_OFF},
  {HB_TAG ('c','p','s','p'), HB_AAT_LAYOUT_FEATURE_TYPE_CASE_SENSITIVE_LAYOUT,   HB_AAT_LAYOUT_SELECTOR_CASE_SENSITIVE_SPACING_ON,      HB_AAT_LAYOUT_SELECTOR_CASE_SENSITIVE_SPACING_OFF},
  {HB_TAG ('c','s','w','h'), HB_AAT_LAYOUT_FEATURE_TYPE_CONTEXTUAL_ALTERNATIVES, HB_AAT_LAYOUT_SELECTOR_CONTEXTUAL_SWASH_ALTERNATES_ON, HB_AAT_LAYOUT_SELECTOR_CONTEXTUAL_SWASH_ALTERNATES_OFF},
  {HB_TAG ('d','l','i','g'), HB_AAT_LAYOUT_FEATURE_TYPE_LIGATURES,               HB_AAT_LAYOUT_SELECTOR_RARE_LIGATURES_ON,              HB_AAT_LAYOUT_SELECTOR_RARE_LIGATURES_OFF},
  {HB_TAG ('e','x','p','t'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_EXPERT_CHARACTERS,              (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('f','r','a','c'), HB_AAT_LAYOUT_FEATURE_TYPE_FRACTIONS,               HB_AAT_LAYOUT_SELECTOR_DIAGONAL_FRACTIONS,             HB_AAT_LAYOUT_SELECTOR_NO_FRACTIONS},
  {HB_TAG ('f','w','i','d'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_MONOSPACED_TEXT,                (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('h','a','l','t'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_ALT_HALF_WIDTH_TEXT,            (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('h','i','s','t'), HB_AAT_LAYOUT_FEATURE_TYPE_LIGATURES,               HB_AAT_LAYOUT_SELECTOR_HISTORICAL_LIGATURES_ON,        HB_AAT_LAYOUT_SELECTOR_HISTORICAL_LIGATURES_OFF},
  {HB_TAG ('h','k','n','a'), HB_AAT_LAYOUT_FEATURE_TYPE_ALTERNATE_KANA,          HB_AAT_LAYOUT_SELECTOR_ALTERNATE_HORIZ_KANA_ON,        HB_AAT_LAYOUT_SELECTOR_ALTERNATE_HORIZ_KANA_OFF},
  {HB_TAG ('h','l','i','g'), HB_AAT_LAYOUT_FEATURE_TYPE_LIGATURES,               HB_AAT_LAYOUT_SELECTOR_HISTORICAL_LIGATURES_ON,        HB_AAT_LAYOUT_SELECTOR_HISTORICAL_LIGATURES_OFF},
  {HB_TAG ('h','n','g','l'), HB_AAT_LAYOUT_FEATURE_TYPE_TRANSLITERATION,         HB_AAT_LAYOUT_SELECTOR_HANJA_TO_HANGUL,                HB_AAT_LAYOUT_SELECTOR_NO_TRANSLITERATION},
  {HB_TAG ('h','o','j','o'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_HOJO_CHARACTERS,                (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('h','w','i','d'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_HALF_WIDTH_TEXT,                (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('i','t','a','l'), HB_AAT_LAYOUT_FEATURE_TYPE_ITALIC_CJK_ROMAN,        HB_AAT_LAYOUT_SELECTOR_CJK_ITALIC_ROMAN_ON,            HB_AAT_LAYOUT_SELECTOR_CJK_ITALIC_ROMAN_OFF},
  {HB_TAG ('j','p','0','4'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_JIS2004_CHARACTERS,             (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('j','p','7','8'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_JIS1978_CHARACTERS,             (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('j','p','8','3'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_JIS1983_CHARACTERS,             (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('j','p','9','0'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_JIS1990_CHARACTERS,             (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('l','i','g','a'), HB_AAT_LAYOUT_FEATURE_TYPE_LIGATURES,               HB_AAT_LAYOUT_SELECTOR_COMMON_LIGATURES_ON,            HB_AAT_LAYOUT_SELECTOR_COMMON_LIGATURES_OFF},
  {HB_TAG ('l','n','u','m'), HB_AAT_LAYOUT_FEATURE_TYPE_NUMBER_CASE,             HB_AAT_LAYOUT_SELECTOR_UPPER_CASE_NUMBERS,             (hb_aat_layout_feature_setting_t) 2},
  {HB_TAG ('m','g','r','k'), HB_AAT_LAYOUT_FEATURE_TYPE_MATHEMATICAL_EXTRAS,     HB_AAT_LAYOUT_SELECTOR_MATHEMATICAL_GREEK_ON,          HB_AAT_LAYOUT_SELECTOR_MATHEMATICAL_GREEK_OFF},
  {HB_TAG ('n','l','c','k'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_NLCCHARACTERS,                  (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('o','n','u','m'), HB_AAT_LAYOUT_FEATURE_TYPE_NUMBER_CASE,             HB_AAT_LAYOUT_SELECTOR_LOWER_CASE_NUMBERS,             (hb_aat_layout_feature_setting_t) 2},
  {HB_TAG ('o','r','d','n'), HB_AAT_LAYOUT_FEATURE_TYPE_VERTICAL_POSITION,       HB_AAT_LAYOUT_SELECTOR_ORDINALS,                       HB_AAT_LAYOUT_SELECTOR_NORMAL_POSITION},
  {HB_TAG ('p','a','l','t'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_ALT_PROPORTIONAL_TEXT,          (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('p','c','a','p'), HB_AAT_LAYOUT_FEATURE_TYPE_LOWER_CASE,              HB_AAT_LAYOUT_SELECTOR_LOWER_CASE_PETITE_CAPS,         HB_AAT_LAYOUT_SELECTOR_DEFAULT_LOWER_CASE},
  {HB_TAG ('p','k','n','a'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_PROPORTIONAL_TEXT,              (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('p','n','u','m'), HB_AAT_LAYOUT_FEATURE_TYPE_NUMBER_SPACING,          HB_AAT_LAYOUT_SELECTOR_PROPORTIONAL_NUMBERS,           (hb_aat_layout_feature_setting_t) 4},
  {HB_TAG ('p','w','i','d'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_PROPORTIONAL_TEXT,              (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('q','w','i','d'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_QUARTER_WIDTH_TEXT,             (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('r','u','b','y'), HB_AAT_LAYOUT_FEATURE_TYPE_RUBY_KANA,               HB_AAT_LAYOUT_SELECTOR_RUBY_KANA_ON,                   HB_AAT_LAYOUT_SELECTOR_RUBY_KANA_OFF},
  {HB_TAG ('s','i','n','f'), HB_AAT_LAYOUT_FEATURE_TYPE_VERTICAL_POSITION,       HB_AAT_LAYOUT_SELECTOR_SCIENTIFIC_INFERIORS,           HB_AAT_LAYOUT_SELECTOR_NORMAL_POSITION},
  {HB_TAG ('s','m','c','p'), HB_AAT_LAYOUT_FEATURE_TYPE_LOWER_CASE,              HB_AAT_LAYOUT_SELECTOR_LOWER_CASE_SMALL_CAPS,          HB_AAT_LAYOUT_SELECTOR_DEFAULT_LOWER_CASE},
  {HB_TAG ('s','m','p','l'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_SIMPLIFIED_CHARACTERS,          (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('s','s','0','1'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_ONE_ON,           HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_ONE_OFF},
  {HB_TAG ('s','s','0','2'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_TWO_ON,           HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_TWO_OFF},
  {HB_TAG ('s','s','0','3'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_THREE_ON,         HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_THREE_OFF},
  {HB_TAG ('s','s','0','4'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_FOUR_ON,          HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_FOUR_OFF},
  {HB_TAG ('s','s','0','5'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_FIVE_ON,          HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_FIVE_OFF},
  {HB_TAG ('s','s','0','6'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_SIX_ON,           HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_SIX_OFF},
  {HB_TAG ('s','s','0','7'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_SEVEN_ON,         HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_SEVEN_OFF},
  {HB_TAG ('s','s','0','8'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_EIGHT_ON,         HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_EIGHT_OFF},
  {HB_TAG ('s','s','0','9'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_NINE_ON,          HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_NINE_OFF},
  {HB_TAG ('s','s','1','0'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_TEN_ON,           HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_TEN_OFF},
  {HB_TAG ('s','s','1','1'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_ELEVEN_ON,        HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_ELEVEN_OFF},
  {HB_TAG ('s','s','1','2'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_TWELVE_ON,        HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_TWELVE_OFF},
  {HB_TAG ('s','s','1','3'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_THIRTEEN_ON,      HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_THIRTEEN_OFF},
  {HB_TAG ('s','s','1','4'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_FOURTEEN_ON,      HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_FOURTEEN_OFF},
  {HB_TAG ('s','s','1','5'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_FIFTEEN_ON,       HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_FIFTEEN_OFF},
  {HB_TAG ('s','s','1','6'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_SIXTEEN_ON,       HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_SIXTEEN_OFF},
  {HB_TAG ('s','s','1','7'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_SEVENTEEN_ON,     HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_SEVENTEEN_OFF},
  {HB_TAG ('s','s','1','8'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_EIGHTEEN_ON,      HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_EIGHTEEN_OFF},
  {HB_TAG ('s','s','1','9'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_NINETEEN_ON,      HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_NINETEEN_OFF},
  {HB_TAG ('s','s','2','0'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLISTIC_ALTERNATIVES,  HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_TWENTY_ON,        HB_AAT_LAYOUT_SELECTOR_STYLISTIC_ALT_TWENTY_OFF},
  {HB_TAG ('s','u','b','s'), HB_AAT_LAYOUT_FEATURE_TYPE_VERTICAL_POSITION,       HB_AAT_LAYOUT_SELECTOR_INFERIORS,                      HB_AAT_LAYOUT_SELECTOR_NORMAL_POSITION},
  {HB_TAG ('s','u','p','s'), HB_AAT_LAYOUT_FEATURE_TYPE_VERTICAL_POSITION,       HB_AAT_LAYOUT_SELECTOR_SUPERIORS,                      HB_AAT_LAYOUT_SELECTOR_NORMAL_POSITION},
  {HB_TAG ('s','w','s','h'), HB_AAT_LAYOUT_FEATURE_TYPE_CONTEXTUAL_ALTERNATIVES, HB_AAT_LAYOUT_SELECTOR_SWASH_ALTERNATES_ON,            HB_AAT_LAYOUT_SELECTOR_SWASH_ALTERNATES_OFF},
  {HB_TAG ('t','i','t','l'), HB_AAT_LAYOUT_FEATURE_TYPE_STYLE_OPTIONS,           HB_AAT_LAYOUT_SELECTOR_TITLING_CAPS,                   HB_AAT_LAYOUT_SELECTOR_NO_STYLE_OPTIONS},
  {HB_TAG ('t','n','a','m'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_TRADITIONAL_NAMES_CHARACTERS,   (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('t','n','u','m'), HB_AAT_LAYOUT_FEATURE_TYPE_NUMBER_SPACING,          HB_AAT_LAYOUT_SELECTOR_MONOSPACED_NUMBERS,             (hb_aat_layout_feature_setting_t) 4},
  {HB_TAG ('t','r','a','d'), HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_SHAPE,         HB_AAT_LAYOUT_SELECTOR_TRADITIONAL_CHARACTERS,         (hb_aat_layout_feature_setting_t) 16},
  {HB_TAG ('t','w','i','d'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_THIRD_WIDTH_TEXT,               (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('u','n','i','c'), HB_AAT_LAYOUT_FEATURE_TYPE_LETTER_CASE,             (hb_aat_layout_feature_setting_t) 14,                  (hb_aat_layout_feature_setting_t) 15},
  {HB_TAG ('v','a','l','t'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_ALT_PROPORTIONAL_TEXT,          (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('v','e','r','t'), HB_AAT_LAYOUT_FEATURE_TYPE_VERTICAL_SUBSTITUTION,   HB_AAT_LAYOUT_SELECTOR_SUBSTITUTE_VERTICAL_FORMS_ON,   HB_AAT_LAYOUT_SELECTOR_SUBSTITUTE_VERTICAL_FORMS_OFF},
  {HB_TAG ('v','h','a','l'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_ALT_HALF_WIDTH_TEXT,            (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('v','k','n','a'), HB_AAT_LAYOUT_FEATURE_TYPE_ALTERNATE_KANA,          HB_AAT_LAYOUT_SELECTOR_ALTERNATE_VERT_KANA_ON,         HB_AAT_LAYOUT_SELECTOR_ALTERNATE_VERT_KANA_OFF},
  {HB_TAG ('v','p','a','l'), HB_AAT_LAYOUT_FEATURE_TYPE_TEXT_SPACING,            HB_AAT_LAYOUT_SELECTOR_ALT_PROPORTIONAL_TEXT,          (hb_aat_layout_feature_setting_t) 7},
  {HB_TAG ('v','r','t','2'), HB_AAT_LAYOUT_FEATURE_TYPE_VERTICAL_SUBSTITUTION,   HB_AAT_LAYOUT_SELECTOR_SUBSTITUTE_VERTICAL_FORMS_ON,   HB_AAT_LAYOUT_SELECTOR_SUBSTITUTE_VERTICAL_FORMS_OFF},
  {HB_TAG ('z','e','r','o'), HB_AAT_LAYOUT_FEATURE_TYPE_TYPOGRAPHIC_EXTRAS,      HB_AAT_LAYOUT_SELECTOR_SLASHED_ZERO_ON,                HB_AAT_LAYOUT_SELECTOR_SLASHED_ZERO_OFF},
};

const hb_aat_feature_mapping_t *
hb_aat_layout_find_feature_mapping (hb_tag_t tag)
{
  return (const hb_aat_feature_mapping_t *) bsearch (&tag,
						     feature_mappings,
						     ARRAY_LENGTH (feature_mappings),
						     sizeof (feature_mappings[0]),
						     hb_aat_feature_mapping_t::cmp);
}


/*
 * hb_aat_apply_context_t
 */

AAT::hb_aat_apply_context_t::hb_aat_apply_context_t (const hb_ot_shape_plan_t *plan_,
						     hb_font_t *font_,
						     hb_buffer_t *buffer_,
						     hb_blob_t *blob) :
						       plan (plan_),
						       font (font_),
						       face (font->face),
						       buffer (buffer_),
						       sanitizer (),
						       ankr_table (&Null(AAT::ankr)),
						       ankr_end (nullptr),
						       lookup_index (0),
						       debug_depth (0)
{
  sanitizer.init (blob);
  sanitizer.set_num_glyphs (face->get_num_glyphs ());
  sanitizer.start_processing ();
  sanitizer.set_max_ops (HB_SANITIZE_MAX_OPS_MAX);
}

AAT::hb_aat_apply_context_t::~hb_aat_apply_context_t (void)
{
  sanitizer.end_processing ();
}

void
AAT::hb_aat_apply_context_t::set_ankr_table (const AAT::ankr *ankr_table_,
					     const char      *ankr_end_)
{
  ankr_table = ankr_table_;
  ankr_end = ankr_end_;
}


/*
 * mort/morx/kerx/trak
 */


void
hb_aat_layout_compile_map (const hb_aat_map_builder_t *mapper,
			   hb_aat_map_t *map)
{
  const AAT::morx& morx = *mapper->face->table.morx;
  if (morx.has_data ())
  {
    morx.compile_flags (mapper, map);
    return;
  }

  const AAT::mort& mort = *mapper->face->table.mort;
  if (mort.has_data ())
  {
    mort.compile_flags (mapper, map);
    return;
  }
}


bool
hb_aat_layout_has_substitution (hb_face_t *face)
{
  return face->table.morx->has_data () ||
	 face->table.mort->has_data ();
}

void
hb_aat_layout_substitute (const hb_ot_shape_plan_t *plan,
			  hb_font_t *font,
			  hb_buffer_t *buffer)
{
  hb_blob_t *morx_blob = font->face->table.morx.get_blob ();
  const AAT::morx& morx = *morx_blob->as<AAT::morx> ();
  if (morx.has_data ())
  {
    AAT::hb_aat_apply_context_t c (plan, font, buffer, morx_blob);
    morx.apply (&c);
    return;
  }

  hb_blob_t *mort_blob = font->face->table.mort.get_blob ();
  const AAT::mort& mort = *mort_blob->as<AAT::mort> ();
  if (mort.has_data ())
  {
    AAT::hb_aat_apply_context_t c (plan, font, buffer, mort_blob);
    mort.apply (&c);
    return;
  }
}

void
hb_aat_layout_zero_width_deleted_glyphs (hb_buffer_t *buffer)
{
  unsigned int count = buffer->len;
  hb_glyph_info_t *info = buffer->info;
  hb_glyph_position_t *pos = buffer->pos;
  for (unsigned int i = 0; i < count; i++)
    if (unlikely (info[i].codepoint == AAT::DELETED_GLYPH))
      pos[i].x_advance = pos[i].y_advance = pos[i].x_offset = pos[i].y_offset = 0;
}

static bool
is_deleted_glyph (const hb_glyph_info_t *info)
{
  return info->codepoint == AAT::DELETED_GLYPH;
}

void
hb_aat_layout_remove_deleted_glyphs (hb_buffer_t *buffer)
{
  hb_ot_layout_delete_glyphs_inplace (buffer, is_deleted_glyph);
}



bool
hb_aat_layout_has_positioning (hb_face_t *face)
{
  return face->table.kerx->has_data ();
}

void
hb_aat_layout_position (const hb_ot_shape_plan_t *plan,
			hb_font_t *font,
			hb_buffer_t *buffer)
{
  hb_blob_t *kerx_blob = font->face->table.kerx.get_blob ();
  const AAT::kerx& kerx = *kerx_blob->as<AAT::kerx> ();

  hb_blob_t *ankr_blob = font->face->table.ankr.get_blob ();;
  const AAT::ankr& ankr = *font->face->table.ankr;

  AAT::hb_aat_apply_context_t c (plan, font, buffer, kerx_blob);
  c.set_ankr_table (&ankr, ankr_blob->data + ankr_blob->length);
  kerx.apply (&c);
}


bool
hb_aat_layout_has_tracking (hb_face_t *face)
{
  return face->table.trak->has_data ();
}

void
hb_aat_layout_track (const hb_ot_shape_plan_t *plan,
		     hb_font_t *font,
		     hb_buffer_t *buffer)
{
  const AAT::trak& trak = *font->face->table.trak;

  AAT::hb_aat_apply_context_t c (plan, font, buffer);
  trak.apply (&c);
}


hb_language_t
_hb_aat_language_get (hb_face_t *face,
		      unsigned int i)
{
  return face->table.ltag->get_language (i);
}

/**
 * hb_aat_layout_get_features:
 *
 * Since: REPLACEME
 */
unsigned int
hb_aat_layout_get_features (hb_face_t                    *face,
			    unsigned int                  start_offset,
			    unsigned int                 *count,   /* IN/OUT.  May be NULL. */
			    hb_aat_layout_feature_type_t *features /* OUT.     May be NULL. */)
{
  return face->table.feat->get_features (start_offset, count, features);
}

/**
 * hb_aat_layout_get_feature_name_id:
 *
 * Since: REPLACEME
 */
hb_ot_name_id_t
hb_aat_layout_get_feature_name_id (hb_face_t                    *face,
				   hb_aat_layout_feature_type_t  feature)
{ return face->table.feat->get_feature_name_id (feature); }

/**
 * hb_aat_layout_get_feature_settings:
 *
 * Since: REPLACEME
 */
unsigned int
hb_aat_layout_get_feature_settings (hb_face_t                       *face,
				    hb_aat_layout_feature_type_t     feature,
				    hb_aat_layout_feature_setting_t *default_setting, /* OUT.     May be NULL. */
				    unsigned int                     start_offset,
				    unsigned int                    *count,           /* IN/OUT.  May be NULL. */
				    hb_aat_layout_feature_setting_t *settings         /* OUT.     May be NULL. */)
{
  return face->table.feat->get_settings (feature, default_setting,
					 start_offset, count, settings);
}

/**
 * hb_aat_layout_get_feature_setting_name_id:
 *
 * Since: REPLACEME
 */
hb_ot_name_id_t
hb_aat_layout_get_feature_setting_name_id (hb_face_t                       *face,
					   hb_aat_layout_feature_type_t     feature,
					   hb_aat_layout_feature_setting_t  setting)
{ return face->table.feat->get_feature_setting_name_id (feature, setting); }