Add CoreText HB-NG shaper backend on Mac

Change-Id: Ida705b9fc59d41a04cb754faae58774bfc2e656c
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>

2 files changed, 858 insertions, 0 deletions

diff --git a/src/3rdparty/harfbuzz-ng/src/hb-coretext.cc b/src/3rdparty/harfbuzz-ng/src/hb-coretext.cc
new file mode 100644
index 0000000000..87dd779751
--- /dev/null
+++ b/src/3rdparty/harfbuzz-ng/src/hb-coretext.cc
@@ -0,0 +1,812 @@
+/*
+ * Copyright © 2012,2013  Mozilla Foundation.
+ * Copyright © 2012,2013  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.
+ *
+ * Mozilla Author(s): Jonathan Kew
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#define HB_SHAPER coretext
+#include "hb-shaper-impl-private.hh"
+
+#include "hb-coretext.h"
+
+
+#ifndef HB_DEBUG_CORETEXT
+#define HB_DEBUG_CORETEXT (HB_DEBUG+0)
+#endif
+
+
+HB_SHAPER_DATA_ENSURE_DECLARE(coretext, face)
+HB_SHAPER_DATA_ENSURE_DECLARE(coretext, font)
+
+
+/*
+ * shaper face data
+ */
+
+struct hb_coretext_shaper_face_data_t {
+  CGFontRef cg_font;
+};
+
+static void
+release_data (void *info, const void *data, size_t size)
+{
+  assert (hb_blob_get_length ((hb_blob_t *) info) == size &&
+          hb_blob_get_data ((hb_blob_t *) info, NULL) == data);
+
+  hb_blob_destroy ((hb_blob_t *) info);
+}
+
+hb_coretext_shaper_face_data_t *
+_hb_coretext_shaper_face_data_create (hb_face_t *face)
+{
+  hb_coretext_shaper_face_data_t *data = (hb_coretext_shaper_face_data_t *) calloc (1, sizeof (hb_coretext_shaper_face_data_t));
+  if (unlikely (!data))
+    return NULL;
+
+  hb_blob_t *blob = hb_face_reference_blob (face);
+  unsigned int blob_length;
+  const char *blob_data = hb_blob_get_data (blob, &blob_length);
+  if (unlikely (!blob_length))
+    DEBUG_MSG (CORETEXT, face, "Face has empty blob");
+
+  CGDataProviderRef provider = CGDataProviderCreateWithData (blob, blob_data, blob_length, &release_data);
+  data->cg_font = CGFontCreateWithDataProvider (provider);
+  CGDataProviderRelease (provider);
+
+  if (unlikely (!data->cg_font)) {
+    DEBUG_MSG (CORETEXT, face, "Face CGFontCreateWithDataProvider() failed");
+    free (data);
+    return NULL;
+  }
+
+  return data;
+}
+
+void
+_hb_coretext_shaper_face_data_destroy (hb_coretext_shaper_face_data_t *data)
+{
+  CFRelease (data->cg_font);
+  free (data);
+}
+
+CGFontRef
+hb_coretext_face_get_cg_font (hb_face_t *face)
+{
+  if (unlikely (!hb_coretext_shaper_face_data_ensure (face))) return NULL;
+  hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
+  return face_data->cg_font;
+}
+
+
+/*
+ * shaper font data
+ */
+
+struct hb_coretext_shaper_font_data_t {
+  CTFontRef ct_font;
+};
+
+hb_coretext_shaper_font_data_t *
+_hb_coretext_shaper_font_data_create (hb_font_t *font)
+{
+  if (unlikely (!hb_coretext_shaper_face_data_ensure (font->face))) return NULL;
+
+  hb_coretext_shaper_font_data_t *data = (hb_coretext_shaper_font_data_t *) calloc (1, sizeof (hb_coretext_shaper_font_data_t));
+  if (unlikely (!data))
+    return NULL;
+
+  hb_face_t *face = font->face;
+  hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
+
+  data->ct_font = CTFontCreateWithGraphicsFont (face_data->cg_font, font->y_scale, NULL, NULL);
+  if (unlikely (!data->ct_font)) {
+    DEBUG_MSG (CORETEXT, font, "Font CTFontCreateWithGraphicsFont() failed");
+    free (data);
+    return NULL;
+  }
+
+  return data;
+}
+
+void
+_hb_coretext_shaper_font_data_destroy (hb_coretext_shaper_font_data_t *data)
+{
+  CFRelease (data->ct_font);
+  free (data);
+}
+
+
+/*
+ * shaper shape_plan data
+ */
+
+struct hb_coretext_shaper_shape_plan_data_t {};
+
+hb_coretext_shaper_shape_plan_data_t *
+_hb_coretext_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
+					     const hb_feature_t *user_features HB_UNUSED,
+					     unsigned int        num_user_features HB_UNUSED)
+{
+  return (hb_coretext_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
+}
+
+void
+_hb_coretext_shaper_shape_plan_data_destroy (hb_coretext_shaper_shape_plan_data_t *data HB_UNUSED)
+{
+}
+
+CTFontRef
+hb_coretext_font_get_ct_font (hb_font_t *font)
+{
+  if (unlikely (!hb_coretext_shaper_font_data_ensure (font))) return NULL;
+  hb_coretext_shaper_font_data_t *font_data = HB_SHAPER_DATA_GET (font);
+  return font_data->ct_font;
+}
+
+
+/*
+ * shaper
+ */
+
+struct feature_record_t {
+  unsigned int feature;
+  unsigned int setting;
+};
+
+struct active_feature_t {
+  feature_record_t rec;
+  unsigned int order;
+
+  static int cmp (const active_feature_t *a, const active_feature_t *b) {
+    return a->rec.feature < b->rec.feature ? -1 : a->rec.feature > b->rec.feature ? 1 :
+	   a->order < b->order ? -1 : a->order > b->order ? 1 :
+	   a->rec.setting < b->rec.setting ? -1 : a->rec.setting > b->rec.setting ? 1 :
+	   0;
+  }
+  bool operator== (const active_feature_t *f) {
+    return cmp (this, f) == 0;
+  }
+};
+
+struct feature_event_t {
+  unsigned int index;
+  bool start;
+  active_feature_t feature;
+
+  static int cmp (const feature_event_t *a, const feature_event_t *b) {
+    return a->index < b->index ? -1 : a->index > b->index ? 1 :
+	   a->start < b->start ? -1 : a->start > b->start ? 1 :
+	   active_feature_t::cmp (&a->feature, &b->feature);
+  }
+};
+
+struct range_record_t {
+  CTFontRef font;
+  unsigned int index_first; /* == start */
+  unsigned int index_last;  /* == end - 1 */
+};
+
+
+/* The following enum members are added in OS X 10.8. */
+#define kAltHalfWidthTextSelector		6
+#define kAltProportionalTextSelector		5
+#define kAlternateHorizKanaOffSelector		1
+#define kAlternateHorizKanaOnSelector		0
+#define kAlternateKanaType			34
+#define kAlternateVertKanaOffSelector		3
+#define kAlternateVertKanaOnSelector		2
+#define kCaseSensitiveLayoutOffSelector		1
+#define kCaseSensitiveLayoutOnSelector		0
+#define kCaseSensitiveLayoutType		33
+#define kCaseSensitiveSpacingOffSelector	3
+#define kCaseSensitiveSpacingOnSelector		2
+#define kContextualAlternatesOffSelector	1
+#define kContextualAlternatesOnSelector		0
+#define kContextualAlternatesType		36
+#define kContextualLigaturesOffSelector		19
+#define kContextualLigaturesOnSelector		18
+#define kContextualSwashAlternatesOffSelector	5
+#define kContextualSwashAlternatesOnSelector	4
+#define kDefaultLowerCaseSelector		0
+#define kDefaultUpperCaseSelector		0
+#define kHistoricalLigaturesOffSelector		21
+#define kHistoricalLigaturesOnSelector		20
+#define kHojoCharactersSelector			12
+#define kJIS2004CharactersSelector		11
+#define kLowerCasePetiteCapsSelector		2
+#define kLowerCaseSmallCapsSelector		1
+#define kLowerCaseType				37
+#define kMathematicalGreekOffSelector		11
+#define kMathematicalGreekOnSelector		10
+#define kNLCCharactersSelector			13
+#define kQuarterWidthTextSelector		4
+#define kScientificInferiorsSelector		4
+#define kStylisticAltEightOffSelector		17
+#define kStylisticAltEightOnSelector		16
+#define kStylisticAltEighteenOffSelector	37
+#define kStylisticAltEighteenOnSelector		36
+#define kStylisticAltElevenOffSelector		23
+#define kStylisticAltElevenOnSelector		22
+#define kStylisticAltFifteenOffSelector		31
+#define kStylisticAltFifteenOnSelector		30
+#define kStylisticAltFiveOffSelector		11
+#define kStylisticAltFiveOnSelector		10
+#define kStylisticAltFourOffSelector		9
+#define kStylisticAltFourOnSelector		8
+#define kStylisticAltFourteenOffSelector	29
+#define kStylisticAltFourteenOnSelector		28
+#define kStylisticAltNineOffSelector		19
+#define kStylisticAltNineOnSelector		18
+#define kStylisticAltNineteenOffSelector	39
+#define kStylisticAltNineteenOnSelector		38
+#define kStylisticAltOneOffSelector		3
+#define kStylisticAltOneOnSelector		2
+#define kStylisticAltSevenOffSelector		15
+#define kStylisticAltSevenOnSelector		14
+#define kStylisticAltSeventeenOffSelector	35
+#define kStylisticAltSeventeenOnSelector	34
+#define kStylisticAltSixOffSelector		13
+#define kStylisticAltSixOnSelector		12
+#define kStylisticAltSixteenOffSelector		33
+#define kStylisticAltSixteenOnSelector		32
+#define kStylisticAltTenOffSelector		21
+#define kStylisticAltTenOnSelector		20
+#define kStylisticAltThirteenOffSelector	27
+#define kStylisticAltThirteenOnSelector		26
+#define kStylisticAltThreeOffSelector		7
+#define kStylisticAltThreeOnSelector		6
+#define kStylisticAltTwelveOffSelector		25
+#define kStylisticAltTwelveOnSelector		24
+#define kStylisticAltTwentyOffSelector		41
+#define kStylisticAltTwentyOnSelector		40
+#define kStylisticAltTwoOffSelector		5
+#define kStylisticAltTwoOnSelector		4
+#define kStylisticAlternativesType		35
+#define kSwashAlternatesOffSelector		3
+#define kSwashAlternatesOnSelector		2
+#define kThirdWidthTextSelector			3
+#define kTraditionalNamesCharactersSelector	14
+#define kUpperCasePetiteCapsSelector		2
+#define kUpperCaseSmallCapsSelector		1
+#define kUpperCaseType				38
+
+/* Table data courtesy of Apple. */
+struct feature_mapping_t {
+    FourCharCode otFeatureTag;
+    uint16_t aatFeatureType;
+    uint16_t selectorToEnable;
+    uint16_t selectorToDisable;
+} feature_mappings[] = {
+    { 'c2pc',   kUpperCaseType,             kUpperCasePetiteCapsSelector,           kDefaultUpperCaseSelector },
+    { 'c2sc',   kUpperCaseType,             kUpperCaseSmallCapsSelector,            kDefaultUpperCaseSelector },
+    { 'calt',   kContextualAlternatesType,  kContextualAlternatesOnSelector,        kContextualAlternatesOffSelector },
+    { 'case',   kCaseSensitiveLayoutType,   kCaseSensitiveLayoutOnSelector,         kCaseSensitiveLayoutOffSelector },
+    { 'clig',   kLigaturesType,             kContextualLigaturesOnSelector,         kContextualLigaturesOffSelector },
+    { 'cpsp',   kCaseSensitiveLayoutType,   kCaseSensitiveSpacingOnSelector,        kCaseSensitiveSpacingOffSelector },
+    { 'cswh',   kContextualAlternatesType,  kContextualSwashAlternatesOnSelector,   kContextualSwashAlternatesOffSelector },
+    { 'dlig',   kLigaturesType,             kRareLigaturesOnSelector,               kRareLigaturesOffSelector },
+    { 'expt',   kCharacterShapeType,        kExpertCharactersSelector,              16 },
+    { 'frac',   kFractionsType,             kDiagonalFractionsSelector,             kNoFractionsSelector },
+    { 'fwid',   kTextSpacingType,           kMonospacedTextSelector,                7 },
+    { 'halt',   kTextSpacingType,           kAltHalfWidthTextSelector,              7 },
+    { 'hist',   kLigaturesType,             kHistoricalLigaturesOnSelector,         kHistoricalLigaturesOffSelector },
+    { 'hkna',   kAlternateKanaType,         kAlternateHorizKanaOnSelector,          kAlternateHorizKanaOffSelector, },
+    { 'hlig',   kLigaturesType,             kHistoricalLigaturesOnSelector,         kHistoricalLigaturesOffSelector },
+    { 'hngl',   kTransliterationType,       kHanjaToHangulSelector,                 kNoTransliterationSelector },
+    { 'hojo',   kCharacterShapeType,        kHojoCharactersSelector,                16 },
+    { 'hwid',   kTextSpacingType,           kHalfWidthTextSelector,                 7 },
+    { 'ital',   kItalicCJKRomanType,        kCJKItalicRomanOnSelector,              kCJKItalicRomanOffSelector },
+    { 'jp04',   kCharacterShapeType,        kJIS2004CharactersSelector,             16 },
+    { 'jp78',   kCharacterShapeType,        kJIS1978CharactersSelector,             16 },
+    { 'jp83',   kCharacterShapeType,        kJIS1983CharactersSelector,             16 },
+    { 'jp90',   kCharacterShapeType,        kJIS1990CharactersSelector,             16 },
+    { 'liga',   kLigaturesType,             kCommonLigaturesOnSelector,             kCommonLigaturesOffSelector },
+    { 'lnum',   kNumberCaseType,            kUpperCaseNumbersSelector,              2 },
+    { 'mgrk',   kMathematicalExtrasType,    kMathematicalGreekOnSelector,           kMathematicalGreekOffSelector },
+    { 'nlck',   kCharacterShapeType,        kNLCCharactersSelector,                 16 },
+    { 'onum',   kNumberCaseType,            kLowerCaseNumbersSelector,              2 },
+    { 'ordn',   kVerticalPositionType,      kOrdinalsSelector,                      kNormalPositionSelector },
+    { 'palt',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
+    { 'pcap',   kLowerCaseType,             kLowerCasePetiteCapsSelector,           kDefaultLowerCaseSelector },
+    { 'pkna',   kTextSpacingType,           kProportionalTextSelector,              7 },
+    { 'pnum',   kNumberSpacingType,         kProportionalNumbersSelector,           4 },
+    { 'pwid',   kTextSpacingType,           kProportionalTextSelector,              7 },
+    { 'qwid',   kTextSpacingType,           kQuarterWidthTextSelector,              7 },
+    { 'ruby',   kRubyKanaType,              kRubyKanaOnSelector,                    kRubyKanaOffSelector },
+    { 'sinf',   kVerticalPositionType,      kScientificInferiorsSelector,           kNormalPositionSelector },
+    { 'smcp',   kLowerCaseType,             kLowerCaseSmallCapsSelector,            kDefaultLowerCaseSelector },
+    { 'smpl',   kCharacterShapeType,        kSimplifiedCharactersSelector,          16 },
+    { 'ss01',   kStylisticAlternativesType, kStylisticAltOneOnSelector,             kStylisticAltOneOffSelector },
+    { 'ss02',   kStylisticAlternativesType, kStylisticAltTwoOnSelector,             kStylisticAltTwoOffSelector },
+    { 'ss03',   kStylisticAlternativesType, kStylisticAltThreeOnSelector,           kStylisticAltThreeOffSelector },
+    { 'ss04',   kStylisticAlternativesType, kStylisticAltFourOnSelector,            kStylisticAltFourOffSelector },
+    { 'ss05',   kStylisticAlternativesType, kStylisticAltFiveOnSelector,            kStylisticAltFiveOffSelector },
+    { 'ss06',   kStylisticAlternativesType, kStylisticAltSixOnSelector,             kStylisticAltSixOffSelector },
+    { 'ss07',   kStylisticAlternativesType, kStylisticAltSevenOnSelector,           kStylisticAltSevenOffSelector },
+    { 'ss08',   kStylisticAlternativesType, kStylisticAltEightOnSelector,           kStylisticAltEightOffSelector },
+    { 'ss09',   kStylisticAlternativesType, kStylisticAltNineOnSelector,            kStylisticAltNineOffSelector },
+    { 'ss10',   kStylisticAlternativesType, kStylisticAltTenOnSelector,             kStylisticAltTenOffSelector },
+    { 'ss11',   kStylisticAlternativesType, kStylisticAltElevenOnSelector,          kStylisticAltElevenOffSelector },
+    { 'ss12',   kStylisticAlternativesType, kStylisticAltTwelveOnSelector,          kStylisticAltTwelveOffSelector },
+    { 'ss13',   kStylisticAlternativesType, kStylisticAltThirteenOnSelector,        kStylisticAltThirteenOffSelector },
+    { 'ss14',   kStylisticAlternativesType, kStylisticAltFourteenOnSelector,        kStylisticAltFourteenOffSelector },
+    { 'ss15',   kStylisticAlternativesType, kStylisticAltFifteenOnSelector,         kStylisticAltFifteenOffSelector },
+    { 'ss16',   kStylisticAlternativesType, kStylisticAltSixteenOnSelector,         kStylisticAltSixteenOffSelector },
+    { 'ss17',   kStylisticAlternativesType, kStylisticAltSeventeenOnSelector,       kStylisticAltSeventeenOffSelector },
+    { 'ss18',   kStylisticAlternativesType, kStylisticAltEighteenOnSelector,        kStylisticAltEighteenOffSelector },
+    { 'ss19',   kStylisticAlternativesType, kStylisticAltNineteenOnSelector,        kStylisticAltNineteenOffSelector },
+    { 'ss20',   kStylisticAlternativesType, kStylisticAltTwentyOnSelector,          kStylisticAltTwentyOffSelector },
+    { 'subs',   kVerticalPositionType,      kInferiorsSelector,                     kNormalPositionSelector },
+    { 'sups',   kVerticalPositionType,      kSuperiorsSelector,                     kNormalPositionSelector },
+    { 'swsh',   kContextualAlternatesType,  kSwashAlternatesOnSelector,             kSwashAlternatesOffSelector },
+    { 'titl',   kStyleOptionsType,          kTitlingCapsSelector,                   kNoStyleOptionsSelector },
+    { 'tnam',   kCharacterShapeType,        kTraditionalNamesCharactersSelector,    16 },
+    { 'tnum',   kNumberSpacingType,         kMonospacedNumbersSelector,             4 },
+    { 'trad',   kCharacterShapeType,        kTraditionalCharactersSelector,         16 },
+    { 'twid',   kTextSpacingType,           kThirdWidthTextSelector,                7 },
+    { 'unic',   kLetterCaseType,            14,                                     15 },
+    { 'valt',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
+    { 'vert',   kVerticalSubstitutionType,  kSubstituteVerticalFormsOnSelector,     kSubstituteVerticalFormsOffSelector },
+    { 'vhal',   kTextSpacingType,           kAltHalfWidthTextSelector,              7 },
+    { 'vkna',   kAlternateKanaType,         kAlternateVertKanaOnSelector,           kAlternateVertKanaOffSelector },
+    { 'vpal',   kTextSpacingType,           kAltProportionalTextSelector,           7 },
+    { 'vrt2',   kVerticalSubstitutionType,  kSubstituteVerticalFormsOnSelector,     kSubstituteVerticalFormsOffSelector },
+    { 'zero',   kTypographicExtrasType,     kSlashedZeroOnSelector,                 kSlashedZeroOffSelector },
+};
+
+static int
+_hb_feature_mapping_cmp (const void *key_, const void *entry_)
+{
+  unsigned int key = * (unsigned int *) key_;
+  const feature_mapping_t * entry = (const feature_mapping_t *) entry_;
+  return key < entry->otFeatureTag ? -1 :
+	 key > entry->otFeatureTag ? 1 :
+	 0;
+}
+
+hb_bool_t
+_hb_coretext_shape (hb_shape_plan_t    *shape_plan,
+		    hb_font_t          *font,
+                    hb_buffer_t        *buffer,
+                    const hb_feature_t *features,
+                    unsigned int        num_features)
+{
+  hb_face_t *face = font->face;
+  hb_coretext_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
+  hb_coretext_shaper_font_data_t *font_data = HB_SHAPER_DATA_GET (font);
+
+  /*
+   * Set up features.
+   * (copied + modified from code from hb-uniscribe.cc)
+   */
+  hb_auto_array_t<feature_record_t> feature_records;
+  hb_auto_array_t<range_record_t> range_records;
+  if (num_features)
+  {
+    /* Sort features by start/end events. */
+    hb_auto_array_t<feature_event_t> feature_events;
+    for (unsigned int i = 0; i < num_features; i++)
+    {
+      const feature_mapping_t * mapping = (const feature_mapping_t *) bsearch (&features[i].tag,
+									       feature_mappings,
+									       ARRAY_LENGTH (feature_mappings),
+									       sizeof (feature_mappings[0]),
+									       _hb_feature_mapping_cmp);
+      if (!mapping)
+        continue;
+
+      active_feature_t feature;
+      feature.rec.feature = mapping->aatFeatureType;
+      feature.rec.setting = features[i].value ? mapping->selectorToEnable : mapping->selectorToDisable;
+      feature.order = i;
+
+      feature_event_t *event;
+
+      event = feature_events.push ();
+      if (unlikely (!event))
+	goto fail_features;
+      event->index = features[i].start;
+      event->start = true;
+      event->feature = feature;
+
+      event = feature_events.push ();
+      if (unlikely (!event))
+	goto fail_features;
+      event->index = features[i].end;
+      event->start = false;
+      event->feature = feature;
+    }
+    feature_events.sort ();
+    /* Add a strategic final event. */
+    {
+      active_feature_t feature;
+      feature.rec.feature = HB_TAG_NONE;
+      feature.rec.setting = 0;
+      feature.order = num_features + 1;
+
+      feature_event_t *event = feature_events.push ();
+      if (unlikely (!event))
+	goto fail_features;
+      event->index = 0; /* This value does magic. */
+      event->start = false;
+      event->feature = feature;
+    }
+
+    /* Scan events and save features for each range. */
+    hb_auto_array_t<active_feature_t> active_features;
+    unsigned int last_index = 0;
+    for (unsigned int i = 0; i < feature_events.len; i++)
+    {
+      feature_event_t *event = &feature_events[i];
+
+      if (event->index != last_index)
+      {
+        /* Save a snapshot of active features and the range. */
+	range_record_t *range = range_records.push ();
+	if (unlikely (!range))
+	  goto fail_features;
+
+	unsigned int offset = feature_records.len;
+
+	if (active_features.len)
+	{
+	  CFMutableArrayRef features_array = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
+
+	  /* TODO sort and resolve conflicting features? */
+	  /* active_features.sort (); */
+	  for (unsigned int j = 0; j < active_features.len; j++)
+	  {
+	    CFStringRef keys[2] = {
+	      kCTFontFeatureTypeIdentifierKey,
+	      kCTFontFeatureSelectorIdentifierKey
+	    };
+	    CFNumberRef values[2] = {
+	      CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.feature),
+	      CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.setting)
+	    };
+	    CFDictionaryRef dict = CFDictionaryCreate (kCFAllocatorDefault,
+						       (const void **) keys,
+						       (const void **) values,
+						       2,
+						       &kCFTypeDictionaryKeyCallBacks,
+						       &kCFTypeDictionaryValueCallBacks);
+	    CFRelease (values[0]);
+	    CFRelease (values[1]);
+
+	    CFArrayAppendValue (features_array, dict);
+	    CFRelease (dict);
+
+	  }
+
+	  CFDictionaryRef attributes = CFDictionaryCreate (kCFAllocatorDefault,
+							   (const void **) &kCTFontFeatureSettingsAttribute,
+							   (const void **) &features_array,
+							   1,
+							   &kCFTypeDictionaryKeyCallBacks,
+							   &kCFTypeDictionaryValueCallBacks);
+	  CFRelease (features_array);
+
+	  CTFontDescriptorRef font_desc = CTFontDescriptorCreateWithAttributes (attributes);
+	  CFRelease (attributes);
+
+	  range->font = CTFontCreateCopyWithAttributes (font_data->ct_font, 0.0, NULL, font_desc);
+
+	  CFRelease (font_desc);
+	}
+	else
+	{
+	  range->font = NULL;
+	}
+
+	range->index_first = last_index;
+	range->index_last  = event->index - 1;
+
+	last_index = event->index;
+      }
+
+      if (event->start) {
+        active_feature_t *feature = active_features.push ();
+	if (unlikely (!feature))
+	  goto fail_features;
+	*feature = event->feature;
+      } else {
+        active_feature_t *feature = active_features.find (&event->feature);
+	if (feature)
+	  active_features.remove (feature - active_features.array);
+      }
+    }
+
+    if (!range_records.len) /* No active feature found. */
+      goto fail_features;
+  }
+  else
+  {
+  fail_features:
+    num_features = 0;
+  }
+
+#define FAIL(...) \
+  HB_STMT_START { \
+    DEBUG_MSG (CORETEXT, NULL, __VA_ARGS__); \
+    return false; \
+  } HB_STMT_END;
+
+  unsigned int scratch_size;
+  hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
+
+#define ALLOCATE_ARRAY(Type, name, len) \
+  Type *name = (Type *) scratch; \
+  { \
+    unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
+    assert (_consumed <= scratch_size); \
+    scratch += _consumed; \
+    scratch_size -= _consumed; \
+  }
+
+#define utf16_index() var1.u32
+
+  ALLOCATE_ARRAY (UniChar, pchars, buffer->len * 2);
+
+  unsigned int chars_len = 0;
+  for (unsigned int i = 0; i < buffer->len; i++) {
+    hb_codepoint_t c = buffer->info[i].codepoint;
+    buffer->info[i].utf16_index() = chars_len;
+    if (likely (c < 0x10000))
+      pchars[chars_len++] = c;
+    else if (unlikely (c >= 0x110000))
+      pchars[chars_len++] = 0xFFFD;
+    else {
+      pchars[chars_len++] = 0xD800 + ((c - 0x10000) >> 10);
+      pchars[chars_len++] = 0xDC00 + ((c - 0x10000) & ((1 << 10) - 1));
+    }
+  }
+
+#undef utf16_index
+
+  CFStringRef string_ref = CFStringCreateWithCharactersNoCopy (NULL,
+                                                               pchars, chars_len,
+                                                               kCFAllocatorNull);
+
+  CFMutableAttributedStringRef attr_string = CFAttributedStringCreateMutable (NULL, chars_len);
+  CFAttributedStringReplaceString (attr_string, CFRangeMake (0, 0), string_ref);
+  CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
+				  kCTFontAttributeName, font_data->ct_font);
+
+  if (num_features)
+  {
+    ALLOCATE_ARRAY (unsigned int, log_clusters, chars_len);
+
+    /* Need log_clusters to assign features. */
+    chars_len = 0;
+    for (unsigned int i = 0; i < buffer->len; i++)
+    {
+      hb_codepoint_t c = buffer->info[i].codepoint;
+      unsigned int cluster = buffer->info[i].cluster;
+      log_clusters[chars_len++] = cluster;
+      if (c >= 0x10000 && c < 0x110000)
+	log_clusters[chars_len++] = cluster; /* Surrogates. */
+    }
+
+    unsigned int start = 0;
+    range_record_t *last_range = &range_records[0];
+    for (unsigned int k = 0; k < chars_len; k++)
+    {
+      range_record_t *range = last_range;
+      while (log_clusters[k] < range->index_first)
+	range--;
+      while (log_clusters[k] > range->index_last)
+	range++;
+      if (range != last_range)
+      {
+        if (last_range->font)
+	  CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, k - start),
+					  kCTFontAttributeName, last_range->font);
+
+	start = k;
+      }
+
+      last_range = range;
+    }
+    if (start != chars_len && last_range->font)
+      CFAttributedStringSetAttribute (attr_string, CFRangeMake (start, chars_len - start - 1),
+				      kCTFontAttributeName, last_range->font);
+
+    for (unsigned int i = 0; i < range_records.len; i++)
+      if (range_records[i].font)
+	CFRelease (range_records[i].font);
+  }
+
+  CTLineRef line = CTLineCreateWithAttributedString (attr_string);
+  CFRelease (attr_string);
+
+  CFArrayRef glyph_runs = CTLineGetGlyphRuns (line);
+  unsigned int num_runs = CFArrayGetCount (glyph_runs);
+
+  buffer->len = 0;
+
+  const CFRange range_all = CFRangeMake (0, 0);
+
+  for (unsigned int i = 0; i < num_runs; i++)
+  {
+    CTRunRef run = (CTRunRef) CFArrayGetValueAtIndex (glyph_runs, i);
+
+    /* CoreText does automatic font fallback (AKA "cascading") for  characters
+     * not supported by the requested font, and provides no way to turn it off,
+     * so we detect if the returned run uses a font other than the requested
+     * one and fill in the buffer with .notdef glyphs instead of random glyph
+     * indices from a different font.
+     */
+    CFDictionaryRef attributes = CTRunGetAttributes (run);
+    CTFontRef run_ct_font = static_cast<CTFontRef>(CFDictionaryGetValue (attributes, kCTFontAttributeName));
+    CGFontRef run_cg_font = CTFontCopyGraphicsFont (run_ct_font, 0);
+    if (!CFEqual (run_cg_font, face_data->cg_font))
+    {
+        CFRelease (run_cg_font);
+
+	CFRange range = CTRunGetStringRange (run);
+	buffer->ensure (buffer->len + range.length);
+	if (buffer->in_error)
+	  FAIL ("Buffer resize failed");
+	hb_glyph_info_t *info = buffer->info + buffer->len;
+
+	CGGlyph notdef = 0;
+	double advance = CTFontGetAdvancesForGlyphs (font_data->ct_font, kCTFontHorizontalOrientation, &notdef, NULL, 1);
+
+        for (CFIndex j = range.location; j < range.location + range.length; j++)
+	{
+	    UniChar ch = CFStringGetCharacterAtIndex (string_ref, j);
+	    if (hb_in_range<UniChar> (ch, 0xDC00, 0xDFFF) && range.location < j)
+	    {
+	      ch = CFStringGetCharacterAtIndex (string_ref, j - 1);
+	      if (hb_in_range<UniChar> (ch, 0xD800, 0xDBFF))
+	        /* This is the second of a surrogate pair.  Don't need .notdef
+		 * for this one. */
+	        continue;
+	    }
+
+            info->codepoint = notdef;
+	    /* TODO We have to fixup clusters later.  See vis_clusters in
+	     * hb-uniscribe.cc for example. */
+            info->cluster = j;
+
+            info->mask = advance;
+            info->var1.u32 = 0;
+            info->var2.u32 = 0;
+
+	    info++;
+	    buffer->len++;
+        }
+        continue;
+    }
+    CFRelease (run_cg_font);
+
+    unsigned int num_glyphs = CTRunGetGlyphCount (run);
+    if (num_glyphs == 0)
+      continue;
+
+    buffer->ensure (buffer->len + num_glyphs);
+
+    scratch = buffer->get_scratch_buffer (&scratch_size);
+
+    /* Testing indicates that CTRunGetGlyphsPtr, etc (almost?) always
+     * succeed, and so copying data to our own buffer will be rare. */
+
+    const CGGlyph* glyphs = CTRunGetGlyphsPtr (run);
+    if (!glyphs) {
+      ALLOCATE_ARRAY (CGGlyph, glyph_buf, num_glyphs);
+      CTRunGetGlyphs (run, range_all, glyph_buf);
+      glyphs = glyph_buf;
+    }
+
+    const CGPoint* positions = CTRunGetPositionsPtr (run);
+    if (!positions) {
+      ALLOCATE_ARRAY (CGPoint, position_buf, num_glyphs);
+      CTRunGetPositions (run, range_all, position_buf);
+      positions = position_buf;
+    }
+
+    const CFIndex* string_indices = CTRunGetStringIndicesPtr (run);
+    if (!string_indices) {
+      ALLOCATE_ARRAY (CFIndex, index_buf, num_glyphs);
+      CTRunGetStringIndices (run, range_all, index_buf);
+      string_indices = index_buf;
+    }
+
+#undef ALLOCATE_ARRAY
+
+    double run_width = CTRunGetTypographicBounds (run, range_all, NULL, NULL, NULL);
+
+    for (unsigned int j = 0; j < num_glyphs; j++) {
+      double advance = (j + 1 < num_glyphs ? positions[j + 1].x : positions[0].x + run_width) - positions[j].x;
+
+      hb_glyph_info_t *info = &buffer->info[buffer->len];
+
+      info->codepoint = glyphs[j];
+      info->cluster = string_indices[j];
+
+      /* Currently, we do all x-positioning by setting the advance, we never use x-offset. */
+      info->mask = advance;
+      info->var1.u32 = 0;
+      info->var2.u32 = positions[j].y;
+
+      buffer->len++;
+    }
+  }
+
+  buffer->clear_positions ();
+
+  unsigned int count = buffer->len;
+  for (unsigned int i = 0; i < count; ++i) {
+    hb_glyph_info_t *info = &buffer->info[i];
+    hb_glyph_position_t *pos = &buffer->pos[i];
+
+    /* TODO vertical */
+    pos->x_advance = info->mask;
+    pos->x_offset = info->var1.u32;
+    pos->y_offset = info->var2.u32;
+  }
+
+  /* Fix up clusters so that we never return out-of-order indices;
+   * if core text has reordered glyphs, we'll merge them to the
+   * beginning of the reordered cluster.
+   *
+   * This does *not* mean we'll form the same clusters as Uniscribe
+   * or the native OT backend, only that the cluster indices will be
+   * monotonic in the output buffer. */
+  if (HB_DIRECTION_IS_FORWARD (buffer->props.direction)) {
+    unsigned int prev_cluster = 0;
+    for (unsigned int i = 0; i < count; i++) {
+      unsigned int curr_cluster = buffer->info[i].cluster;
+      if (curr_cluster < prev_cluster) {
+        for (unsigned int j = i; j > 0; j--) {
+          if (buffer->info[j - 1].cluster > curr_cluster)
+            buffer->info[j - 1].cluster = curr_cluster;
+          else
+            break;
+        }
+      }
+      prev_cluster = curr_cluster;
+    }
+  } else {
+    unsigned int prev_cluster = (unsigned int)-1;
+    for (unsigned int i = 0; i < count; i++) {
+      unsigned int curr_cluster = buffer->info[i].cluster;
+      if (curr_cluster > prev_cluster) {
+        for (unsigned int j = i; j > 0; j--) {
+          if (buffer->info[j - 1].cluster < curr_cluster)
+            buffer->info[j - 1].cluster = curr_cluster;
+          else
+            break;
+        }
+      }
+      prev_cluster = curr_cluster;
+    }
+  }
+
+  CFRelease (string_ref);
+  CFRelease (line);
+
+  return true;
+}
diff --git a/src/3rdparty/harfbuzz-ng/src/hb-coretext.h b/src/3rdparty/harfbuzz-ng/src/hb-coretext.h
new file mode 100644
index 0000000000..c4954fa1b2
--- /dev/null
+++ b/src/3rdparty/harfbuzz-ng/src/hb-coretext.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright © 2012  Mozilla Foundation.
+ *
+ *  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.
+ *
+ * Mozilla Author(s): Jonathan Kew
+ */
+
+#ifndef HB_CORETEXT_H
+#define HB_CORETEXT_H
+
+#include "hb.h"
+
+#include <ApplicationServices/ApplicationServices.h>
+
+HB_BEGIN_DECLS
+
+
+CGFontRef
+hb_coretext_face_get_cg_font (hb_face_t *face);
+
+CTFontRef
+hb_coretext_font_get_ct_font (hb_font_t *font);
+
+
+HB_END_DECLS
+
+#endif /* HB_CORETEXT_H */