harfbuzz/src/hb-coretext.cc

1158 lines
38 KiB
C++

/*
* 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
*/
#include "hb.hh"
#ifdef HAVE_CORETEXT
#include "hb-shaper-impl.hh"
#include "hb-coretext.h"
#include "hb-aat-layout.hh"
#include <math.h>
/**
* SECTION:hb-coretext
* @title: hb-coretext
* @short_description: CoreText integration
* @include: hb-coretext.h
*
* Functions for using HarfBuzz with the CoreText fonts.
**/
/* https://developer.apple.com/documentation/coretext/1508745-ctfontcreatewithgraphicsfont */
#define HB_CORETEXT_DEFAULT_FONT_SIZE 12.f
static void
release_table_data (void *user_data)
{
CFDataRef cf_data = reinterpret_cast<CFDataRef> (user_data);
CFRelease(cf_data);
}
static hb_blob_t *
_hb_cg_reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
{
CGFontRef cg_font = reinterpret_cast<CGFontRef> (user_data);
CFDataRef cf_data = CGFontCopyTableForTag (cg_font, tag);
if (unlikely (!cf_data))
return nullptr;
const char *data = reinterpret_cast<const char*> (CFDataGetBytePtr (cf_data));
const size_t length = CFDataGetLength (cf_data);
if (!data || !length)
{
CFRelease (cf_data);
return nullptr;
}
return hb_blob_create (data, length, HB_MEMORY_MODE_READONLY,
reinterpret_cast<void *> (const_cast<__CFData *> (cf_data)),
release_table_data);
}
static void
_hb_cg_font_release (void *data)
{
CGFontRelease ((CGFontRef) data);
}
static CTFontDescriptorRef
get_last_resort_font_desc ()
{
// TODO Handle allocation failures?
CTFontDescriptorRef last_resort = CTFontDescriptorCreateWithNameAndSize (CFSTR("LastResort"), 0);
CFArrayRef cascade_list = CFArrayCreate (kCFAllocatorDefault,
(const void **) &last_resort,
1,
&kCFTypeArrayCallBacks);
CFRelease (last_resort);
CFDictionaryRef attributes = CFDictionaryCreate (kCFAllocatorDefault,
(const void **) &kCTFontCascadeListAttribute,
(const void **) &cascade_list,
1,
&kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks);
CFRelease (cascade_list);
CTFontDescriptorRef font_desc = CTFontDescriptorCreateWithAttributes (attributes);
CFRelease (attributes);
return font_desc;
}
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, nullptr) == data);
hb_blob_destroy ((hb_blob_t *) info);
}
static CGFontRef
create_cg_font (hb_face_t *face)
{
CGFontRef cg_font = nullptr;
if (face->destroy == _hb_cg_font_release)
{
cg_font = CGFontRetain ((CGFontRef) face->user_data);
}
else
{
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);
if (likely (provider))
{
cg_font = CGFontCreateWithDataProvider (provider);
if (unlikely (!cg_font))
DEBUG_MSG (CORETEXT, face, "Face CGFontCreateWithDataProvider() failed");
CGDataProviderRelease (provider);
}
}
return cg_font;
}
static CTFontRef
create_ct_font (CGFontRef cg_font, CGFloat font_size)
{
CTFontRef ct_font = nullptr;
/* CoreText does not enable trak table usage / tracking when creating a CTFont
* using CTFontCreateWithGraphicsFont. The only way of enabling tracking seems
* to be through the CTFontCreateUIFontForLanguage call. */
CFStringRef cg_postscript_name = CGFontCopyPostScriptName (cg_font);
if (CFStringHasPrefix (cg_postscript_name, CFSTR (".SFNSText")) ||
CFStringHasPrefix (cg_postscript_name, CFSTR (".SFNSDisplay")))
{
#if !(defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) && MAC_OS_X_VERSION_MIN_REQUIRED < 1080
# define kCTFontUIFontSystem kCTFontSystemFontType
# define kCTFontUIFontEmphasizedSystem kCTFontEmphasizedSystemFontType
#endif
CTFontUIFontType font_type = kCTFontUIFontSystem;
if (CFStringHasSuffix (cg_postscript_name, CFSTR ("-Bold")))
font_type = kCTFontUIFontEmphasizedSystem;
ct_font = CTFontCreateUIFontForLanguage (font_type, font_size, nullptr);
CFStringRef ct_result_name = CTFontCopyPostScriptName(ct_font);
if (CFStringCompare (ct_result_name, cg_postscript_name, 0) != kCFCompareEqualTo)
{
CFRelease(ct_font);
ct_font = nullptr;
}
CFRelease (ct_result_name);
}
CFRelease (cg_postscript_name);
if (!ct_font)
ct_font = CTFontCreateWithGraphicsFont (cg_font, font_size, nullptr, nullptr);
if (unlikely (!ct_font)) {
DEBUG_MSG (CORETEXT, cg_font, "Font CTFontCreateWithGraphicsFont() failed");
return nullptr;
}
/* crbug.com/576941 and crbug.com/625902 and the investigation in the latter
* bug indicate that the cascade list reconfiguration occasionally causes
* crashes in CoreText on OS X 10.9, thus let's skip this step on older
* operating system versions. Except for the emoji font, where _not_
* reconfiguring the cascade list causes CoreText crashes. For details, see
* crbug.com/549610 */
// 0x00070000 stands for "kCTVersionNumber10_10", see CoreText.h
if (&CTGetCoreTextVersion != nullptr && CTGetCoreTextVersion() < 0x00070000) {
CFStringRef fontName = CTFontCopyPostScriptName (ct_font);
bool isEmojiFont = CFStringCompare (fontName, CFSTR("AppleColorEmoji"), 0) == kCFCompareEqualTo;
CFRelease (fontName);
if (!isEmojiFont)
return ct_font;
}
CFURLRef original_url = nullptr;
#if !(defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) && MAC_OS_X_VERSION_MIN_REQUIRED < 1060
ATSFontRef atsFont;
FSRef fsref;
OSStatus status;
atsFont = CTFontGetPlatformFont (ct_font, NULL);
status = ATSFontGetFileReference (atsFont, &fsref);
if (status == noErr)
original_url = CFURLCreateFromFSRef (NULL, &fsref);
#else
original_url = (CFURLRef) CTFontCopyAttribute (ct_font, kCTFontURLAttribute);
#endif
/* Create font copy with cascade list that has LastResort first; this speeds up CoreText
* font fallback which we don't need anyway. */
{
CTFontDescriptorRef last_resort_font_desc = get_last_resort_font_desc ();
CTFontRef new_ct_font = CTFontCreateCopyWithAttributes (ct_font, 0.0, nullptr, last_resort_font_desc);
CFRelease (last_resort_font_desc);
if (new_ct_font)
{
/* The CTFontCreateCopyWithAttributes call fails to stay on the same font
* when reconfiguring the cascade list and may switch to a different font
* when there are fonts that go by the same name, since the descriptor is
* just name and size.
*
* Avoid reconfiguring the cascade lists if the new font is outside the
* system locations that we cannot access from the sandboxed renderer
* process in Blink. This can be detected by the new file URL location
* that the newly found font points to. */
CFURLRef new_url = nullptr;
#if !(defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) && MAC_OS_X_VERSION_MIN_REQUIRED < 1060
atsFont = CTFontGetPlatformFont (new_ct_font, NULL);
status = ATSFontGetFileReference (atsFont, &fsref);
if (status == noErr)
new_url = CFURLCreateFromFSRef (NULL, &fsref);
#else
new_url = (CFURLRef) CTFontCopyAttribute (new_ct_font, kCTFontURLAttribute);
#endif
// Keep reconfigured font if URL cannot be retrieved (seems to be the case
// on Mac OS 10.12 Sierra), speculative fix for crbug.com/625606
if (!original_url || !new_url || CFEqual (original_url, new_url)) {
CFRelease (ct_font);
ct_font = new_ct_font;
} else {
CFRelease (new_ct_font);
DEBUG_MSG (CORETEXT, ct_font, "Discarding reconfigured CTFont, location changed.");
}
if (new_url)
CFRelease (new_url);
}
else
DEBUG_MSG (CORETEXT, ct_font, "Font copy with empty cascade list failed");
}
if (original_url)
CFRelease (original_url);
return ct_font;
}
hb_coretext_face_data_t *
_hb_coretext_shaper_face_data_create (hb_face_t *face)
{
CGFontRef cg_font = create_cg_font (face);
if (unlikely (!cg_font))
{
DEBUG_MSG (CORETEXT, face, "CGFont creation failed..");
return nullptr;
}
return (hb_coretext_face_data_t *) cg_font;
}
void
_hb_coretext_shaper_face_data_destroy (hb_coretext_face_data_t *data)
{
CFRelease ((CGFontRef) data);
}
hb_face_t *
hb_coretext_face_create (CGFontRef cg_font)
{
return hb_face_create_for_tables (_hb_cg_reference_table, CGFontRetain (cg_font), _hb_cg_font_release);
}
/*
* Since: 0.9.10
*/
CGFontRef
hb_coretext_face_get_cg_font (hb_face_t *face)
{
return (CGFontRef) (const void *) face->data.coretext;
}
hb_coretext_font_data_t *
_hb_coretext_shaper_font_data_create (hb_font_t *font)
{
hb_face_t *face = font->face;
const hb_coretext_face_data_t *face_data = face->data.coretext;
if (unlikely (!face_data)) return nullptr;
CGFontRef cg_font = (CGFontRef) (const void *) face->data.coretext;
CGFloat font_size = (CGFloat) (font->ptem <= 0.f ? HB_CORETEXT_DEFAULT_FONT_SIZE : font->ptem);
CTFontRef ct_font = create_ct_font (cg_font, font_size);
if (unlikely (!ct_font))
{
DEBUG_MSG (CORETEXT, font, "CGFont creation failed..");
return nullptr;
}
return (hb_coretext_font_data_t *) ct_font;
}
void
_hb_coretext_shaper_font_data_destroy (hb_coretext_font_data_t *data)
{
CFRelease ((CTFontRef) data);
}
static const hb_coretext_font_data_t *
hb_coretext_font_data_sync (hb_font_t *font)
{
retry:
const hb_coretext_font_data_t *data = font->data.coretext;
if (unlikely (!data)) return nullptr;
if (fabs (CTFontGetSize ((CTFontRef) data) - (CGFloat) font->ptem) > .5)
{
/* XXX-MT-bug
* Note that evaluating condition above can be dangerous if another thread
* got here first and destructed data. That's, as always, bad use pattern.
* If you modify the font (change font size), other threads must not be
* using it at the same time. However, since this check is delayed to
* when one actually tries to shape something, this is a XXX race condition
* (and the only one we have that I know of) right now. Ie. you modify the
* font size in one thread, then (supposedly safely) try to use it from two
* or more threads and BOOM! I'm not sure how to fix this. We want RCU.
*/
/* Drop and recreate. */
/* If someone dropped it in the mean time, throw it away and don't touch it.
* Otherwise, destruct it. */
if (likely (font->data.coretext.cmpexch (const_cast<hb_coretext_font_data_t *> (data), nullptr)))
_hb_coretext_shaper_font_data_destroy (const_cast<hb_coretext_font_data_t *> (data));
else
goto retry;
}
return font->data.coretext;
}
/*
* Since: 1.7.2
*/
hb_font_t *
hb_coretext_font_create (CTFontRef ct_font)
{
CGFontRef cg_font = CTFontCopyGraphicsFont (ct_font, nullptr);
hb_face_t *face = hb_coretext_face_create (cg_font);
CFRelease (cg_font);
hb_font_t *font = hb_font_create (face);
hb_face_destroy (face);
if (unlikely (hb_object_is_immutable (font)))
return font;
hb_font_set_ptem (font, CTFontGetSize (ct_font));
/* Let there be dragons here... */
font->data.coretext.cmpexch (nullptr, (hb_coretext_font_data_t *) CFRetain (ct_font));
return font;
}
CTFontRef
hb_coretext_font_get_ct_font (hb_font_t *font)
{
const hb_coretext_font_data_t *data = hb_coretext_font_data_sync (font);
return data ? (CTFontRef) data : nullptr;
}
/*
* shaper
*/
struct feature_record_t {
unsigned int feature;
unsigned int setting;
};
struct active_feature_t {
feature_record_t rec;
unsigned int order;
HB_INTERNAL static int cmp (const void *pa, const void *pb) {
const active_feature_t *a = (const active_feature_t *) pa;
const active_feature_t *b = (const active_feature_t *) pb;
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;
HB_INTERNAL static int cmp (const void *pa, const void *pb) {
const feature_event_t *a = (const feature_event_t *) pa;
const feature_event_t *b = (const feature_event_t *) pb;
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 */
};
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;
CGFontRef cg_font = (CGFontRef) (const void *) face->data.coretext;
CTFontRef ct_font = (CTFontRef) hb_coretext_font_data_sync (font);
CGFloat ct_font_size = CTFontGetSize (ct_font);
CGFloat x_mult = (CGFloat) font->x_scale / ct_font_size;
CGFloat y_mult = (CGFloat) font->y_scale / ct_font_size;
/* Attach marks to their bases, to match the 'ot' shaper.
* Adapted from a very old version of hb-ot-shape:hb_form_clusters().
* Note that this only makes us be closer to the 'ot' shaper,
* but by no means the same. For example, if there's
* B1 M1 B2 M2, and B1-B2 form a ligature, M2's cluster will
* continue pointing to B2 even though B2 was merged into B1's
* cluster... */
if (buffer->cluster_level == HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES)
{
hb_unicode_funcs_t *unicode = buffer->unicode;
unsigned int count = buffer->len;
hb_glyph_info_t *info = buffer->info;
for (unsigned int i = 1; i < count; i++)
if (HB_UNICODE_GENERAL_CATEGORY_IS_MARK (unicode->general_category (info[i].codepoint)))
buffer->merge_clusters (i - 1, i + 1);
}
hb_vector_t<feature_record_t> feature_records;
hb_vector_t<range_record_t> range_records;
/*
* Set up features.
* (copied + modified from code from hb-uniscribe.cc)
*/
if (num_features)
{
/* Sort features by start/end events. */
hb_vector_t<feature_event_t> feature_events;
for (unsigned int i = 0; i < num_features; i++)
{
active_feature_t feature;
#if MAC_OS_X_VERSION_MIN_REQUIRED < 1010
const hb_aat_feature_mapping_t * mapping = hb_aat_layout_find_feature_mapping (features[i].tag);
if (!mapping)
continue;
feature.rec.feature = mapping->aatFeatureType;
feature.rec.setting = features[i].value ? mapping->selectorToEnable : mapping->selectorToDisable;
#else
feature.rec.feature = features[i].tag;
feature.rec.setting = features[i].value;
#endif
feature.order = i;
feature_event_t *event;
event = feature_events.push ();
event->index = features[i].start;
event->start = true;
event->feature = feature;
event = feature_events.push ();
event->index = features[i].end;
event->start = false;
event->feature = feature;
}
feature_events.qsort ();
/* 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 ();
event->index = 0; /* This value does magic. */
event->start = false;
event->feature = feature;
}
/* Scan events and save features for each range. */
hb_vector_t<active_feature_t> active_features;
unsigned int last_index = 0;
for (unsigned int i = 0; i < feature_events.length; 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 (active_features.length)
{
CFMutableArrayRef features_array = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
/* TODO sort and resolve conflicting features? */
/* active_features.qsort (); */
for (unsigned int j = 0; j < active_features.length; j++)
{
#if MAC_OS_X_VERSION_MIN_REQUIRED < 1010
CFStringRef keys[] = {
kCTFontFeatureTypeIdentifierKey,
kCTFontFeatureSelectorIdentifierKey
};
CFNumberRef values[] = {
CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.feature),
CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.setting)
};
#else
char tag[5] = {HB_UNTAG (active_features[j].rec.feature)};
CFTypeRef keys[] = {
kCTFontOpenTypeFeatureTag,
kCTFontOpenTypeFeatureValue
};
CFTypeRef values[] = {
CFStringCreateWithCString (kCFAllocatorDefault, tag, kCFStringEncodingASCII),
CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &active_features[j].rec.setting)
};
#endif
static_assert ((ARRAY_LENGTH_CONST (keys) == ARRAY_LENGTH_CONST (values)), "");
CFDictionaryRef dict = CFDictionaryCreate (kCFAllocatorDefault,
(const void **) keys,
(const void **) values,
ARRAY_LENGTH (keys),
&kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks);
for (unsigned int i = 0; i < ARRAY_LENGTH (values); i++)
CFRelease (values[i]);
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 (ct_font, 0.0, nullptr, font_desc);
CFRelease (font_desc);
}
else
{
range->font = nullptr;
}
range->index_first = last_index;
range->index_last = event->index - 1;
last_index = event->index;
}
if (event->start)
{
active_features.push (event->feature);
} else {
active_feature_t *feature = active_features.find (&event->feature);
if (feature)
active_features.remove (feature - active_features.arrayZ);
}
}
}
unsigned int scratch_size;
hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
#define ALLOCATE_ARRAY(Type, name, len, on_no_room) \
Type *name = (Type *) scratch; \
do { \
unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
if (unlikely (_consumed > scratch_size)) \
{ \
on_no_room; \
assert (0); \
} \
scratch += _consumed; \
scratch_size -= _consumed; \
} while (0)
ALLOCATE_ARRAY (UniChar, pchars, buffer->len * 2, /*nothing*/);
unsigned int chars_len = 0;
for (unsigned int i = 0; i < buffer->len; i++) {
hb_codepoint_t c = buffer->info[i].codepoint;
if (likely (c <= 0xFFFFu))
pchars[chars_len++] = c;
else if (unlikely (c > 0x10FFFFu))
pchars[chars_len++] = 0xFFFDu;
else {
pchars[chars_len++] = 0xD800u + ((c - 0x10000u) >> 10);
pchars[chars_len++] = 0xDC00u + ((c - 0x10000u) & ((1u << 10) - 1));
}
}
ALLOCATE_ARRAY (unsigned int, log_clusters, chars_len, /*nothing*/);
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 (hb_in_range (c, 0x10000u, 0x10FFFFu))
log_clusters[chars_len++] = cluster; /* Surrogates. */
}
#define FAIL(...) \
HB_STMT_START { \
DEBUG_MSG (CORETEXT, nullptr, __VA_ARGS__); \
ret = false; \
goto fail; \
} HB_STMT_END
bool ret = true;
CFStringRef string_ref = nullptr;
CTLineRef line = nullptr;
if (false)
{
resize_and_retry:
DEBUG_MSG (CORETEXT, buffer, "Buffer resize");
/* string_ref uses the scratch-buffer for backing store, and line references
* string_ref (via attr_string). We must release those before resizing buffer. */
assert (string_ref);
assert (line);
CFRelease (string_ref);
CFRelease (line);
string_ref = nullptr;
line = nullptr;
/* Get previous start-of-scratch-area, that we use later for readjusting
* our existing scratch arrays. */
unsigned int old_scratch_used;
hb_buffer_t::scratch_buffer_t *old_scratch;
old_scratch = buffer->get_scratch_buffer (&old_scratch_used);
old_scratch_used = scratch - old_scratch;
if (unlikely (!buffer->ensure (buffer->allocated * 2)))
FAIL ("Buffer resize failed");
/* Adjust scratch, pchars, and log_cluster arrays. This is ugly, but really the
* cleanest way to do without completely restructuring the rest of this shaper. */
scratch = buffer->get_scratch_buffer (&scratch_size);
pchars = reinterpret_cast<UniChar *> (((char *) scratch + ((char *) pchars - (char *) old_scratch)));
log_clusters = reinterpret_cast<unsigned int *> (((char *) scratch + ((char *) log_clusters - (char *) old_scratch)));
scratch += old_scratch_used;
scratch_size -= old_scratch_used;
}
{
string_ref = CFStringCreateWithCharactersNoCopy (nullptr,
pchars, chars_len,
kCFAllocatorNull);
if (unlikely (!string_ref))
FAIL ("CFStringCreateWithCharactersNoCopy failed");
/* Create an attributed string, populate it, and create a line from it, then release attributed string. */
{
CFMutableAttributedStringRef attr_string = CFAttributedStringCreateMutable (kCFAllocatorDefault,
chars_len);
if (unlikely (!attr_string))
FAIL ("CFAttributedStringCreateMutable failed");
CFAttributedStringReplaceString (attr_string, CFRangeMake (0, 0), string_ref);
if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
{
CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
kCTVerticalFormsAttributeName, kCFBooleanTrue);
}
if (buffer->props.language)
{
/* What's the iOS equivalent of this check?
* The symbols was introduced in iOS 7.0.
* At any rate, our fallback is safe and works fine. */
#if !(defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) && MAC_OS_X_VERSION_MIN_REQUIRED < 1090
# define kCTLanguageAttributeName CFSTR ("NSLanguage")
#endif
CFStringRef lang = CFStringCreateWithCStringNoCopy (kCFAllocatorDefault,
hb_language_to_string (buffer->props.language),
kCFStringEncodingUTF8,
kCFAllocatorNull);
if (unlikely (!lang))
{
CFRelease (attr_string);
FAIL ("CFStringCreateWithCStringNoCopy failed");
}
CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
kCTLanguageAttributeName, lang);
CFRelease (lang);
}
CFAttributedStringSetAttribute (attr_string, CFRangeMake (0, chars_len),
kCTFontAttributeName, ct_font);
if (num_features && range_records.length)
{
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),
kCTFontAttributeName, last_range->font);
}
/* Enable/disable kern if requested.
*
* Note: once kern is disabled, reenabling it doesn't currently seem to work in CoreText.
*/
if (num_features)
{
unsigned int zeroint = 0;
CFNumberRef zero = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &zeroint);
for (unsigned int i = 0; i < num_features; i++)
{
const hb_feature_t &feature = features[i];
if (feature.tag == HB_TAG('k','e','r','n') &&
feature.start < chars_len && feature.start < feature.end)
{
CFRange feature_range = CFRangeMake (feature.start,
hb_min (feature.end, chars_len) - feature.start);
if (feature.value)
CFAttributedStringRemoveAttribute (attr_string, feature_range, kCTKernAttributeName);
else
CFAttributedStringSetAttribute (attr_string, feature_range, kCTKernAttributeName, zero);
}
}
CFRelease (zero);
}
int level = HB_DIRECTION_IS_FORWARD (buffer->props.direction) ? 0 : 1;
CFNumberRef level_number = CFNumberCreate (kCFAllocatorDefault, kCFNumberIntType, &level);
#if !(defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) && MAC_OS_X_VERSION_MIN_REQUIRED < 1060
extern const CFStringRef kCTTypesetterOptionForcedEmbeddingLevel;
#endif
CFDictionaryRef options = CFDictionaryCreate (kCFAllocatorDefault,
(const void **) &kCTTypesetterOptionForcedEmbeddingLevel,
(const void **) &level_number,
1,
&kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks);
CFRelease (level_number);
if (unlikely (!options))
{
CFRelease (attr_string);
FAIL ("CFDictionaryCreate failed");
}
CTTypesetterRef typesetter = CTTypesetterCreateWithAttributedStringAndOptions (attr_string, options);
CFRelease (options);
CFRelease (attr_string);
if (unlikely (!typesetter))
FAIL ("CTTypesetterCreateWithAttributedStringAndOptions failed");
line = CTTypesetterCreateLine (typesetter, CFRangeMake(0, 0));
CFRelease (typesetter);
if (unlikely (!line))
FAIL ("CTTypesetterCreateLine failed");
}
CFArrayRef glyph_runs = CTLineGetGlyphRuns (line);
unsigned int num_runs = CFArrayGetCount (glyph_runs);
DEBUG_MSG (CORETEXT, nullptr, "Num runs: %d", num_runs);
buffer->len = 0;
uint32_t status_and = ~0, status_or = 0;
double advances_so_far = 0;
/* For right-to-left runs, CoreText returns the glyphs positioned such that
* any trailing whitespace is to the left of (0,0). Adjust coordinate system
* to fix for that. Test with any RTL string with trailing spaces.
* https://crbug.com/469028
*/
if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
{
advances_so_far -= CTLineGetTrailingWhitespaceWidth (line);
if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
advances_so_far = -advances_so_far;
}
const CFRange range_all = CFRangeMake (0, 0);
for (unsigned int i = 0; i < num_runs; i++)
{
CTRunRef run = static_cast<CTRunRef>(CFArrayGetValueAtIndex (glyph_runs, i));
CTRunStatus run_status = CTRunGetStatus (run);
status_or |= run_status;
status_and &= run_status;
DEBUG_MSG (CORETEXT, run, "CTRunStatus: %x", run_status);
double run_advance = CTRunGetTypographicBounds (run, range_all, nullptr, nullptr, nullptr);
if (HB_DIRECTION_IS_VERTICAL (buffer->props.direction))
run_advance = -run_advance;
DEBUG_MSG (CORETEXT, run, "Run advance: %g", run_advance);
/* 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 must 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));
if (!CFEqual (run_ct_font, ct_font))
{
/* The run doesn't use our main font instance. We have to figure out
* whether font fallback happened, or this is just CoreText giving us
* another CTFont using the same underlying CGFont. CoreText seems
* to do that in a variety of situations, one of which being vertical
* text, but also perhaps for caching reasons.
*
* First, see if it uses any of our subfonts created to set font features...
*
* Next, compare the CGFont to the one we used to create our fonts.
* Even this doesn't work all the time.
*
* Finally, we compare PS names, which I don't think are unique...
*
* Looks like if we really want to be sure here we have to modify the
* font to change the name table, similar to what we do in the uniscribe
* backend.
*
* However, even that wouldn't work if we were passed in the CGFont to
* construct a hb_face to begin with.
*
* See: https://github.com/harfbuzz/harfbuzz/pull/36
*
* Also see: https://bugs.chromium.org/p/chromium/issues/detail?id=597098
*/
bool matched = false;
for (unsigned int i = 0; i < range_records.length; i++)
if (range_records[i].font && CFEqual (run_ct_font, range_records[i].font))
{
matched = true;
break;
}
if (!matched)
{
CGFontRef run_cg_font = CTFontCopyGraphicsFont (run_ct_font, nullptr);
if (run_cg_font)
{
matched = CFEqual (run_cg_font, cg_font);
CFRelease (run_cg_font);
}
}
if (!matched)
{
CFStringRef font_ps_name = CTFontCopyName (ct_font, kCTFontPostScriptNameKey);
CFStringRef run_ps_name = CTFontCopyName (run_ct_font, kCTFontPostScriptNameKey);
CFComparisonResult result = CFStringCompare (run_ps_name, font_ps_name, 0);
CFRelease (run_ps_name);
CFRelease (font_ps_name);
if (result == kCFCompareEqualTo)
matched = true;
}
if (!matched)
{
CFRange range = CTRunGetStringRange (run);
DEBUG_MSG (CORETEXT, run, "Run used fallback font: %ld..%ld",
range.location, range.location + range.length);
if (!buffer->ensure_inplace (buffer->len + range.length))
goto resize_and_retry;
hb_glyph_info_t *info = buffer->info + buffer->len;
hb_codepoint_t notdef = 0;
hb_direction_t dir = buffer->props.direction;
hb_position_t x_advance, y_advance, x_offset, y_offset;
hb_font_get_glyph_advance_for_direction (font, notdef, dir, &x_advance, &y_advance);
hb_font_get_glyph_origin_for_direction (font, notdef, dir, &x_offset, &y_offset);
hb_position_t advance = x_advance + y_advance;
x_offset = -x_offset;
y_offset = -y_offset;
unsigned int old_len = buffer->len;
for (CFIndex j = range.location; j < range.location + range.length; j++)
{
UniChar ch = CFStringGetCharacterAtIndex (string_ref, j);
if (hb_in_range<UniChar> (ch, 0xDC00u, 0xDFFFu) && range.location < j)
{
ch = CFStringGetCharacterAtIndex (string_ref, j - 1);
if (hb_in_range<UniChar> (ch, 0xD800u, 0xDBFFu))
/* This is the second of a surrogate pair. Don't need .notdef
* for this one. */
continue;
}
if (buffer->unicode->is_default_ignorable (ch))
continue;
info->codepoint = notdef;
info->cluster = log_clusters[j];
info->mask = advance;
info->var1.i32 = x_offset;
info->var2.i32 = y_offset;
info++;
buffer->len++;
}
if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
buffer->reverse_range (old_len, buffer->len);
advances_so_far += run_advance;
continue;
}
}
unsigned int num_glyphs = CTRunGetGlyphCount (run);
if (num_glyphs == 0)
continue;
if (!buffer->ensure_inplace (buffer->len + num_glyphs))
goto resize_and_retry;
hb_glyph_info_t *run_info = buffer->info + buffer->len;
/* Testing used to indicate that CTRunGetGlyphsPtr, etc (almost?) always
* succeed, and so copying data to our own buffer will be rare. Reports
* have it that this changed in OS X 10.10 Yosemite, and nullptr is returned
* frequently. At any rate, we can test that codepath by setting USE_PTR
* to false. */
#define USE_PTR true
#define SCRATCH_SAVE() \
unsigned int scratch_size_saved = scratch_size; \
hb_buffer_t::scratch_buffer_t *scratch_saved = scratch
#define SCRATCH_RESTORE() \
scratch_size = scratch_size_saved; \
scratch = scratch_saved
{ /* Setup glyphs */
SCRATCH_SAVE();
const CGGlyph* glyphs = USE_PTR ? CTRunGetGlyphsPtr (run) : nullptr;
if (!glyphs) {
ALLOCATE_ARRAY (CGGlyph, glyph_buf, num_glyphs, goto resize_and_retry);
CTRunGetGlyphs (run, range_all, glyph_buf);
glyphs = glyph_buf;
}
const CFIndex* string_indices = USE_PTR ? CTRunGetStringIndicesPtr (run) : nullptr;
if (!string_indices) {
ALLOCATE_ARRAY (CFIndex, index_buf, num_glyphs, goto resize_and_retry);
CTRunGetStringIndices (run, range_all, index_buf);
string_indices = index_buf;
}
hb_glyph_info_t *info = run_info;
for (unsigned int j = 0; j < num_glyphs; j++)
{
info->codepoint = glyphs[j];
info->cluster = log_clusters[string_indices[j]];
info++;
}
SCRATCH_RESTORE();
}
{
/* Setup positions.
* Note that CoreText does not return advances for glyphs. As such,
* for all but last glyph, we use the delta position to next glyph as
* advance (in the advance direction only), and for last glyph we set
* whatever is needed to make the whole run's advance add up. */
SCRATCH_SAVE();
const CGPoint* positions = USE_PTR ? CTRunGetPositionsPtr (run) : nullptr;
if (!positions) {
ALLOCATE_ARRAY (CGPoint, position_buf, num_glyphs, goto resize_and_retry);
CTRunGetPositions (run, range_all, position_buf);
positions = position_buf;
}
hb_glyph_info_t *info = run_info;
if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
{
hb_position_t x_offset = (positions[0].x - advances_so_far) * x_mult;
for (unsigned int j = 0; j < num_glyphs; j++)
{
double advance;
if (likely (j + 1 < num_glyphs))
advance = positions[j + 1].x - positions[j].x;
else /* last glyph */
advance = run_advance - (positions[j].x - positions[0].x);
info->mask = advance * x_mult;
info->var1.i32 = x_offset;
info->var2.i32 = positions[j].y * y_mult;
info++;
}
}
else
{
hb_position_t y_offset = (positions[0].y - advances_so_far) * y_mult;
for (unsigned int j = 0; j < num_glyphs; j++)
{
double advance;
if (likely (j + 1 < num_glyphs))
advance = positions[j + 1].y - positions[j].y;
else /* last glyph */
advance = run_advance - (positions[j].y - positions[0].y);
info->mask = advance * y_mult;
info->var1.i32 = positions[j].x * x_mult;
info->var2.i32 = y_offset;
info++;
}
}
SCRATCH_RESTORE();
advances_so_far += run_advance;
}
#undef SCRATCH_RESTORE
#undef SCRATCH_SAVE
#undef USE_PTR
#undef ALLOCATE_ARRAY
buffer->len += num_glyphs;
}
/* Mac OS 10.6 doesn't have kCTTypesetterOptionForcedEmbeddingLevel,
* or if it does, it doesn't respect it. So we get runs with wrong
* directions. As such, disable the assert... It wouldn't crash, but
* cursoring will be off...
*
* https://crbug.com/419769
*/
if (false)
{
/* Make sure all runs had the expected direction. */
HB_UNUSED bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
assert (bool (status_and & kCTRunStatusRightToLeft) == backward);
assert (bool (status_or & kCTRunStatusRightToLeft) == backward);
}
buffer->clear_positions ();
unsigned int count = buffer->len;
hb_glyph_info_t *info = buffer->info;
hb_glyph_position_t *pos = buffer->pos;
if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
for (unsigned int i = 0; i < count; i++)
{
pos->x_advance = info->mask;
pos->x_offset = info->var1.i32;
pos->y_offset = info->var2.i32;
info++, pos++;
}
else
for (unsigned int i = 0; i < count; i++)
{
pos->y_advance = info->mask;
pos->x_offset = info->var1.i32;
pos->y_offset = info->var2.i32;
info++, pos++;
}
/* 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. CoreText is nice enough
* to tell us whenever it has produced nonmonotonic results...
* Note that we assume the input clusters were nonmonotonic to
* begin with.
*
* 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 (count > 1 && (status_or & kCTRunStatusNonMonotonic))
{
hb_glyph_info_t *info = buffer->info;
if (HB_DIRECTION_IS_FORWARD (buffer->props.direction))
{
unsigned int cluster = info[count - 1].cluster;
for (unsigned int i = count - 1; i > 0; i--)
{
cluster = hb_min (cluster, info[i - 1].cluster);
info[i - 1].cluster = cluster;
}
}
else
{
unsigned int cluster = info[0].cluster;
for (unsigned int i = 1; i < count; i++)
{
cluster = hb_min (cluster, info[i].cluster);
info[i].cluster = cluster;
}
}
}
}
buffer->unsafe_to_break_all ();
#undef FAIL
fail:
if (string_ref)
CFRelease (string_ref);
if (line)
CFRelease (line);
for (unsigned int i = 0; i < range_records.length; i++)
if (range_records[i].font)
CFRelease (range_records[i].font);
return ret;
}
#endif