harfbuzz/src/hb-ot-layout-gsubgpos.hh

4373 lines
137 KiB
C++

/*
* Copyright © 2007,2008,2009,2010 Red Hat, Inc.
* Copyright © 2010,2012 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
*/
#ifndef HB_OT_LAYOUT_GSUBGPOS_HH
#define HB_OT_LAYOUT_GSUBGPOS_HH
#include "hb.hh"
#include "hb-buffer.hh"
#include "hb-map.hh"
#include "hb-set.hh"
#include "hb-ot-map.hh"
#include "hb-ot-layout-common.hh"
#include "hb-ot-layout-gdef-table.hh"
namespace OT {
struct hb_intersects_context_t :
hb_dispatch_context_t<hb_intersects_context_t, bool>
{
template <typename T>
return_t dispatch (const T &obj) { return obj.intersects (this->glyphs); }
static return_t default_return_value () { return false; }
bool stop_sublookup_iteration (return_t r) const { return r; }
const hb_set_t *glyphs;
hb_intersects_context_t (const hb_set_t *glyphs_) :
glyphs (glyphs_) {}
};
struct hb_have_non_1to1_context_t :
hb_dispatch_context_t<hb_have_non_1to1_context_t, bool>
{
template <typename T>
return_t dispatch (const T &obj) { return obj.may_have_non_1to1 (); }
static return_t default_return_value () { return false; }
bool stop_sublookup_iteration (return_t r) const { return r; }
};
struct hb_closure_context_t :
hb_dispatch_context_t<hb_closure_context_t>
{
typedef return_t (*recurse_func_t) (hb_closure_context_t *c, unsigned lookup_index, hb_set_t *covered_seq_indicies, unsigned seq_index, unsigned end_index);
template <typename T>
return_t dispatch (const T &obj) { obj.closure (this); return hb_empty_t (); }
static return_t default_return_value () { return hb_empty_t (); }
void recurse (unsigned lookup_index, hb_set_t *covered_seq_indicies, unsigned seq_index, unsigned end_index)
{
if (unlikely (nesting_level_left == 0 || !recurse_func))
return;
nesting_level_left--;
recurse_func (this, lookup_index, covered_seq_indicies, seq_index, end_index);
nesting_level_left++;
}
void reset_lookup_visit_count ()
{ lookup_count = 0; }
bool lookup_limit_exceeded ()
{ return lookup_count > HB_MAX_LOOKUP_VISIT_COUNT; }
bool should_visit_lookup (unsigned int lookup_index)
{
if (lookup_count++ > HB_MAX_LOOKUP_VISIT_COUNT)
return false;
if (is_lookup_done (lookup_index))
return false;
return true;
}
bool is_lookup_done (unsigned int lookup_index)
{
if (done_lookups_glyph_count->in_error () ||
done_lookups_glyph_set->in_error ())
return true;
/* Have we visited this lookup with the current set of glyphs? */
if (done_lookups_glyph_count->get (lookup_index) != glyphs->get_population ())
{
done_lookups_glyph_count->set (lookup_index, glyphs->get_population ());
if (!done_lookups_glyph_set->has (lookup_index))
{
if (unlikely (!done_lookups_glyph_set->set (lookup_index, hb::unique_ptr<hb_set_t> {hb_set_create ()})))
return true;
}
hb_set_clear (done_lookups_glyph_set->get (lookup_index));
}
hb_set_t *covered_glyph_set = done_lookups_glyph_set->get (lookup_index);
if (unlikely (covered_glyph_set->in_error ()))
return true;
if (parent_active_glyphs ().is_subset (*covered_glyph_set))
return true;
covered_glyph_set->union_ (parent_active_glyphs ());
return false;
}
const hb_set_t& previous_parent_active_glyphs () {
if (active_glyphs_stack.length <= 1)
return *glyphs;
return active_glyphs_stack[active_glyphs_stack.length - 2];
}
const hb_set_t& parent_active_glyphs ()
{
if (!active_glyphs_stack)
return *glyphs;
return active_glyphs_stack.tail ();
}
hb_set_t& push_cur_active_glyphs ()
{
return *active_glyphs_stack.push ();
}
bool pop_cur_done_glyphs ()
{
if (!active_glyphs_stack)
return false;
active_glyphs_stack.pop ();
return true;
}
hb_face_t *face;
hb_set_t *glyphs;
hb_set_t output[1];
hb_vector_t<hb_set_t> active_glyphs_stack;
recurse_func_t recurse_func = nullptr;
unsigned int nesting_level_left;
hb_closure_context_t (hb_face_t *face_,
hb_set_t *glyphs_,
hb_map_t *done_lookups_glyph_count_,
hb_hashmap_t<unsigned, hb::unique_ptr<hb_set_t>> *done_lookups_glyph_set_,
unsigned int nesting_level_left_ = HB_MAX_NESTING_LEVEL) :
face (face_),
glyphs (glyphs_),
nesting_level_left (nesting_level_left_),
done_lookups_glyph_count (done_lookups_glyph_count_),
done_lookups_glyph_set (done_lookups_glyph_set_)
{}
~hb_closure_context_t () { flush (); }
void set_recurse_func (recurse_func_t func) { recurse_func = func; }
void flush ()
{
output->del_range (face->get_num_glyphs (), HB_SET_VALUE_INVALID); /* Remove invalid glyphs. */
glyphs->union_ (*output);
output->clear ();
active_glyphs_stack.pop ();
active_glyphs_stack.reset ();
}
private:
hb_map_t *done_lookups_glyph_count;
hb_hashmap_t<unsigned, hb::unique_ptr<hb_set_t>> *done_lookups_glyph_set;
unsigned int lookup_count = 0;
};
struct hb_closure_lookups_context_t :
hb_dispatch_context_t<hb_closure_lookups_context_t>
{
typedef return_t (*recurse_func_t) (hb_closure_lookups_context_t *c, unsigned lookup_index);
template <typename T>
return_t dispatch (const T &obj) { obj.closure_lookups (this); return hb_empty_t (); }
static return_t default_return_value () { return hb_empty_t (); }
void recurse (unsigned lookup_index)
{
if (unlikely (nesting_level_left == 0 || !recurse_func))
return;
/* Return if new lookup was recursed to before. */
if (lookup_limit_exceeded ()
|| visited_lookups->in_error ()
|| visited_lookups->has (lookup_index))
// Don't increment lookup count here, that will be done in the call to closure_lookups()
// made by recurse_func.
return;
nesting_level_left--;
recurse_func (this, lookup_index);
nesting_level_left++;
}
void set_lookup_visited (unsigned lookup_index)
{ visited_lookups->add (lookup_index); }
void set_lookup_inactive (unsigned lookup_index)
{ inactive_lookups->add (lookup_index); }
bool lookup_limit_exceeded ()
{
bool ret = lookup_count > HB_MAX_LOOKUP_VISIT_COUNT;
if (ret)
DEBUG_MSG (SUBSET, nullptr, "lookup visit count limit exceeded in lookup closure!");
return ret; }
bool is_lookup_visited (unsigned lookup_index)
{
if (unlikely (lookup_count++ > HB_MAX_LOOKUP_VISIT_COUNT))
{
DEBUG_MSG (SUBSET, nullptr, "total visited lookup count %u exceeds max limit, lookup %u is dropped.",
lookup_count, lookup_index);
return true;
}
if (unlikely (visited_lookups->in_error ()))
return true;
return visited_lookups->has (lookup_index);
}
hb_face_t *face;
const hb_set_t *glyphs;
recurse_func_t recurse_func;
unsigned int nesting_level_left;
hb_closure_lookups_context_t (hb_face_t *face_,
const hb_set_t *glyphs_,
hb_set_t *visited_lookups_,
hb_set_t *inactive_lookups_,
unsigned nesting_level_left_ = HB_MAX_NESTING_LEVEL) :
face (face_),
glyphs (glyphs_),
recurse_func (nullptr),
nesting_level_left (nesting_level_left_),
visited_lookups (visited_lookups_),
inactive_lookups (inactive_lookups_),
lookup_count (0) {}
void set_recurse_func (recurse_func_t func) { recurse_func = func; }
private:
hb_set_t *visited_lookups;
hb_set_t *inactive_lookups;
unsigned int lookup_count;
};
struct hb_would_apply_context_t :
hb_dispatch_context_t<hb_would_apply_context_t, bool>
{
template <typename T>
return_t dispatch (const T &obj) { return obj.would_apply (this); }
static return_t default_return_value () { return false; }
bool stop_sublookup_iteration (return_t r) const { return r; }
hb_face_t *face;
const hb_codepoint_t *glyphs;
unsigned int len;
bool zero_context;
hb_would_apply_context_t (hb_face_t *face_,
const hb_codepoint_t *glyphs_,
unsigned int len_,
bool zero_context_) :
face (face_),
glyphs (glyphs_),
len (len_),
zero_context (zero_context_) {}
};
struct hb_collect_glyphs_context_t :
hb_dispatch_context_t<hb_collect_glyphs_context_t>
{
typedef return_t (*recurse_func_t) (hb_collect_glyphs_context_t *c, unsigned int lookup_index);
template <typename T>
return_t dispatch (const T &obj) { obj.collect_glyphs (this); return hb_empty_t (); }
static return_t default_return_value () { return hb_empty_t (); }
void recurse (unsigned int lookup_index)
{
if (unlikely (nesting_level_left == 0 || !recurse_func))
return;
/* Note that GPOS sets recurse_func to nullptr already, so it doesn't get
* past the previous check. For GSUB, we only want to collect the output
* glyphs in the recursion. If output is not requested, we can go home now.
*
* Note further, that the above is not exactly correct. A recursed lookup
* is allowed to match input that is not matched in the context, but that's
* not how most fonts are built. It's possible to relax that and recurse
* with all sets here if it proves to be an issue.
*/
if (output == hb_set_get_empty ())
return;
/* Return if new lookup was recursed to before. */
if (recursed_lookups->has (lookup_index))
return;
hb_set_t *old_before = before;
hb_set_t *old_input = input;
hb_set_t *old_after = after;
before = input = after = hb_set_get_empty ();
nesting_level_left--;
recurse_func (this, lookup_index);
nesting_level_left++;
before = old_before;
input = old_input;
after = old_after;
recursed_lookups->add (lookup_index);
}
hb_face_t *face;
hb_set_t *before;
hb_set_t *input;
hb_set_t *after;
hb_set_t *output;
recurse_func_t recurse_func;
hb_set_t *recursed_lookups;
unsigned int nesting_level_left;
hb_collect_glyphs_context_t (hb_face_t *face_,
hb_set_t *glyphs_before, /* OUT. May be NULL */
hb_set_t *glyphs_input, /* OUT. May be NULL */
hb_set_t *glyphs_after, /* OUT. May be NULL */
hb_set_t *glyphs_output, /* OUT. May be NULL */
unsigned int nesting_level_left_ = HB_MAX_NESTING_LEVEL) :
face (face_),
before (glyphs_before ? glyphs_before : hb_set_get_empty ()),
input (glyphs_input ? glyphs_input : hb_set_get_empty ()),
after (glyphs_after ? glyphs_after : hb_set_get_empty ()),
output (glyphs_output ? glyphs_output : hb_set_get_empty ()),
recurse_func (nullptr),
recursed_lookups (hb_set_create ()),
nesting_level_left (nesting_level_left_) {}
~hb_collect_glyphs_context_t () { hb_set_destroy (recursed_lookups); }
void set_recurse_func (recurse_func_t func) { recurse_func = func; }
};
template <typename set_t>
struct hb_collect_coverage_context_t :
hb_dispatch_context_t<hb_collect_coverage_context_t<set_t>, const Coverage &>
{
typedef const Coverage &return_t; // Stoopid that we have to dupe this here.
template <typename T>
return_t dispatch (const T &obj) { return obj.get_coverage (); }
static return_t default_return_value () { return Null (Coverage); }
bool stop_sublookup_iteration (return_t r) const
{
r.collect_coverage (set);
return false;
}
hb_collect_coverage_context_t (set_t *set_) :
set (set_) {}
set_t *set;
};
struct hb_ot_apply_context_t :
hb_dispatch_context_t<hb_ot_apply_context_t, bool, HB_DEBUG_APPLY>
{
struct matcher_t
{
matcher_t () :
lookup_props (0),
mask (-1),
ignore_zwnj (false),
ignore_zwj (false),
per_syllable (false),
syllable {0},
match_func (nullptr),
match_data (nullptr) {}
typedef bool (*match_func_t) (hb_glyph_info_t &info, unsigned value, const void *data);
void set_ignore_zwnj (bool ignore_zwnj_) { ignore_zwnj = ignore_zwnj_; }
void set_ignore_zwj (bool ignore_zwj_) { ignore_zwj = ignore_zwj_; }
void set_lookup_props (unsigned int lookup_props_) { lookup_props = lookup_props_; }
void set_mask (hb_mask_t mask_) { mask = mask_; }
void set_per_syllable (bool per_syllable_) { per_syllable = per_syllable_; }
void set_syllable (uint8_t syllable_) { syllable = per_syllable ? syllable_ : 0; }
void set_match_func (match_func_t match_func_,
const void *match_data_)
{ match_func = match_func_; match_data = match_data_; }
enum may_match_t {
MATCH_NO,
MATCH_YES,
MATCH_MAYBE
};
may_match_t may_match (hb_glyph_info_t &info,
hb_codepoint_t glyph_data) const
{
if (!(info.mask & mask) ||
(syllable && syllable != info.syllable ()))
return MATCH_NO;
if (match_func)
return match_func (info, glyph_data, match_data) ? MATCH_YES : MATCH_NO;
return MATCH_MAYBE;
}
enum may_skip_t {
SKIP_NO,
SKIP_YES,
SKIP_MAYBE
};
may_skip_t may_skip (const hb_ot_apply_context_t *c,
const hb_glyph_info_t &info) const
{
if (!c->check_glyph_property (&info, lookup_props))
return SKIP_YES;
if (unlikely (_hb_glyph_info_is_default_ignorable_and_not_hidden (&info) &&
(ignore_zwnj || !_hb_glyph_info_is_zwnj (&info)) &&
(ignore_zwj || !_hb_glyph_info_is_zwj (&info))))
return SKIP_MAYBE;
return SKIP_NO;
}
protected:
unsigned int lookup_props;
hb_mask_t mask;
bool ignore_zwnj;
bool ignore_zwj;
bool per_syllable;
uint8_t syllable;
match_func_t match_func;
const void *match_data;
};
struct skipping_iterator_t
{
void init (hb_ot_apply_context_t *c_, bool context_match = false)
{
c = c_;
match_glyph_data16 = nullptr;
#ifndef HB_NO_BEYOND_64K
match_glyph_data24 = nullptr;
#endif
matcher.set_match_func (nullptr, nullptr);
matcher.set_lookup_props (c->lookup_props);
/* Ignore ZWNJ if we are matching GPOS, or matching GSUB context and asked to. */
matcher.set_ignore_zwnj (c->table_index == 1 || (context_match && c->auto_zwnj));
/* Ignore ZWJ if we are matching context, or asked to. */
matcher.set_ignore_zwj (context_match || c->auto_zwj);
matcher.set_mask (context_match ? -1 : c->lookup_mask);
matcher.set_per_syllable (c->per_syllable);
}
void set_lookup_props (unsigned int lookup_props)
{
matcher.set_lookup_props (lookup_props);
}
void set_match_func (matcher_t::match_func_t match_func_,
const void *match_data_)
{
matcher.set_match_func (match_func_, match_data_);
}
void set_glyph_data (const HBUINT16 glyph_data[])
{
match_glyph_data16 = glyph_data;
#ifndef HB_NO_BEYOND_64K
match_glyph_data24 = nullptr;
#endif
}
#ifndef HB_NO_BEYOND_64K
void set_glyph_data (const HBUINT24 glyph_data[])
{
match_glyph_data16 = nullptr;
match_glyph_data24 = glyph_data;
}
#endif
void reset (unsigned int start_index_,
unsigned int num_items_)
{
idx = start_index_;
num_items = num_items_;
end = c->buffer->len;
matcher.set_syllable (start_index_ == c->buffer->idx ? c->buffer->cur().syllable () : 0);
}
void reject ()
{
num_items++;
backup_glyph_data ();
}
matcher_t::may_skip_t
may_skip (const hb_glyph_info_t &info) const
{ return matcher.may_skip (c, info); }
bool next (unsigned *unsafe_to = nullptr)
{
assert (num_items > 0);
while (idx + num_items < end)
{
idx++;
hb_glyph_info_t &info = c->buffer->info[idx];
matcher_t::may_skip_t skip = matcher.may_skip (c, info);
if (unlikely (skip == matcher_t::SKIP_YES))
continue;
matcher_t::may_match_t match = matcher.may_match (info, get_glyph_data ());
if (match == matcher_t::MATCH_YES ||
(match == matcher_t::MATCH_MAYBE &&
skip == matcher_t::SKIP_NO))
{
num_items--;
advance_glyph_data ();
return true;
}
if (skip == matcher_t::SKIP_NO)
{
if (unsafe_to)
*unsafe_to = idx + 1;
return false;
}
}
if (unsafe_to)
*unsafe_to = end;
return false;
}
bool prev (unsigned *unsafe_from = nullptr)
{
assert (num_items > 0);
while (idx > num_items - 1)
{
idx--;
hb_glyph_info_t &info = c->buffer->out_info[idx];
matcher_t::may_skip_t skip = matcher.may_skip (c, info);
if (unlikely (skip == matcher_t::SKIP_YES))
continue;
matcher_t::may_match_t match = matcher.may_match (info, get_glyph_data ());
if (match == matcher_t::MATCH_YES ||
(match == matcher_t::MATCH_MAYBE &&
skip == matcher_t::SKIP_NO))
{
num_items--;
advance_glyph_data ();
return true;
}
if (skip == matcher_t::SKIP_NO)
{
if (unsafe_from)
*unsafe_from = hb_max (1u, idx) - 1u;
return false;
}
}
if (unsafe_from)
*unsafe_from = 0;
return false;
}
hb_codepoint_t
get_glyph_data ()
{
if (match_glyph_data16) return *match_glyph_data16;
#ifndef HB_NO_BEYOND_64K
else
if (match_glyph_data24) return *match_glyph_data24;
#endif
return 0;
}
void
advance_glyph_data ()
{
if (match_glyph_data16) match_glyph_data16++;
#ifndef HB_NO_BEYOND_64K
else
if (match_glyph_data24) match_glyph_data24++;
#endif
}
void
backup_glyph_data ()
{
if (match_glyph_data16) match_glyph_data16--;
#ifndef HB_NO_BEYOND_64K
else
if (match_glyph_data24) match_glyph_data24--;
#endif
}
unsigned int idx;
protected:
hb_ot_apply_context_t *c;
matcher_t matcher;
const HBUINT16 *match_glyph_data16;
#ifndef HB_NO_BEYOND_64K
const HBUINT24 *match_glyph_data24;
#endif
unsigned int num_items;
unsigned int end;
};
const char *get_name () { return "APPLY"; }
typedef return_t (*recurse_func_t) (hb_ot_apply_context_t *c, unsigned int lookup_index);
template <typename T>
return_t dispatch (const T &obj) { return obj.apply (this); }
static return_t default_return_value () { return false; }
bool stop_sublookup_iteration (return_t r) const { return r; }
return_t recurse (unsigned int sub_lookup_index)
{
if (unlikely (nesting_level_left == 0 || !recurse_func || buffer->max_ops-- <= 0))
{
buffer->shaping_failed = true;
return default_return_value ();
}
nesting_level_left--;
bool ret = recurse_func (this, sub_lookup_index);
nesting_level_left++;
return ret;
}
skipping_iterator_t iter_input, iter_context;
unsigned int table_index; /* GSUB/GPOS */
hb_font_t *font;
hb_face_t *face;
hb_buffer_t *buffer;
recurse_func_t recurse_func = nullptr;
const GDEF &gdef;
const VariationStore &var_store;
VariationStore::cache_t *var_store_cache;
hb_direction_t direction;
hb_mask_t lookup_mask = 1;
unsigned int lookup_index = (unsigned) -1;
unsigned int lookup_props = 0;
unsigned int nesting_level_left = HB_MAX_NESTING_LEVEL;
bool has_glyph_classes;
bool auto_zwnj = true;
bool auto_zwj = true;
bool per_syllable = false;
bool random = false;
uint32_t random_state = 1;
unsigned new_syllables = (unsigned) -1;
hb_ot_apply_context_t (unsigned int table_index_,
hb_font_t *font_,
hb_buffer_t *buffer_) :
table_index (table_index_),
font (font_), face (font->face), buffer (buffer_),
gdef (
#ifndef HB_NO_OT_LAYOUT
*face->table.GDEF->table
#else
Null (GDEF)
#endif
),
var_store (gdef.get_var_store ()),
var_store_cache (
#ifndef HB_NO_VAR
table_index == 1 && font->num_coords ? var_store.create_cache () : nullptr
#else
nullptr
#endif
),
direction (buffer_->props.direction),
has_glyph_classes (gdef.has_glyph_classes ())
{ init_iters (); }
~hb_ot_apply_context_t ()
{
#ifndef HB_NO_VAR
VariationStore::destroy_cache (var_store_cache);
#endif
}
void init_iters ()
{
iter_input.init (this, false);
iter_context.init (this, true);
}
void set_lookup_mask (hb_mask_t mask) { lookup_mask = mask; init_iters (); }
void set_auto_zwj (bool auto_zwj_) { auto_zwj = auto_zwj_; init_iters (); }
void set_auto_zwnj (bool auto_zwnj_) { auto_zwnj = auto_zwnj_; init_iters (); }
void set_per_syllable (bool per_syllable_) { per_syllable = per_syllable_; init_iters (); }
void set_random (bool random_) { random = random_; }
void set_recurse_func (recurse_func_t func) { recurse_func = func; }
void set_lookup_index (unsigned int lookup_index_) { lookup_index = lookup_index_; }
void set_lookup_props (unsigned int lookup_props_) { lookup_props = lookup_props_; init_iters (); }
uint32_t random_number ()
{
/* http://www.cplusplus.com/reference/random/minstd_rand/ */
random_state = random_state * 48271 % 2147483647;
return random_state;
}
bool match_properties_mark (hb_codepoint_t glyph,
unsigned int glyph_props,
unsigned int match_props) const
{
/* If using mark filtering sets, the high short of
* match_props has the set index.
*/
if (match_props & LookupFlag::UseMarkFilteringSet)
return gdef.mark_set_covers (match_props >> 16, glyph);
/* The second byte of match_props has the meaning
* "ignore marks of attachment type different than
* the attachment type specified."
*/
if (match_props & LookupFlag::MarkAttachmentType)
return (match_props & LookupFlag::MarkAttachmentType) == (glyph_props & LookupFlag::MarkAttachmentType);
return true;
}
bool check_glyph_property (const hb_glyph_info_t *info,
unsigned int match_props) const
{
hb_codepoint_t glyph = info->codepoint;
unsigned int glyph_props = _hb_glyph_info_get_glyph_props (info);
/* Not covered, if, for example, glyph class is ligature and
* match_props includes LookupFlags::IgnoreLigatures
*/
if (glyph_props & match_props & LookupFlag::IgnoreFlags)
return false;
if (unlikely (glyph_props & HB_OT_LAYOUT_GLYPH_PROPS_MARK))
return match_properties_mark (glyph, glyph_props, match_props);
return true;
}
void _set_glyph_class (hb_codepoint_t glyph_index,
unsigned int class_guess = 0,
bool ligature = false,
bool component = false) const
{
if (new_syllables != (unsigned) -1)
buffer->cur().syllable() = new_syllables;
unsigned int props = _hb_glyph_info_get_glyph_props (&buffer->cur());
props |= HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED;
if (ligature)
{
props |= HB_OT_LAYOUT_GLYPH_PROPS_LIGATED;
/* In the only place that the MULTIPLIED bit is used, Uniscribe
* seems to only care about the "last" transformation between
* Ligature and Multiple substitutions. Ie. if you ligate, expand,
* and ligate again, it forgives the multiplication and acts as
* if only ligation happened. As such, clear MULTIPLIED bit.
*/
props &= ~HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED;
}
if (component)
props |= HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED;
if (likely (has_glyph_classes))
{
props &= HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE;
_hb_glyph_info_set_glyph_props (&buffer->cur(), props | gdef.get_glyph_props (glyph_index));
}
else if (class_guess)
{
props &= HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE;
_hb_glyph_info_set_glyph_props (&buffer->cur(), props | class_guess);
}
else
_hb_glyph_info_set_glyph_props (&buffer->cur(), props);
}
void replace_glyph (hb_codepoint_t glyph_index) const
{
_set_glyph_class (glyph_index);
(void) buffer->replace_glyph (glyph_index);
}
void replace_glyph_inplace (hb_codepoint_t glyph_index) const
{
_set_glyph_class (glyph_index);
buffer->cur().codepoint = glyph_index;
}
void replace_glyph_with_ligature (hb_codepoint_t glyph_index,
unsigned int class_guess) const
{
_set_glyph_class (glyph_index, class_guess, true);
(void) buffer->replace_glyph (glyph_index);
}
void output_glyph_for_component (hb_codepoint_t glyph_index,
unsigned int class_guess) const
{
_set_glyph_class (glyph_index, class_guess, false, true);
(void) buffer->output_glyph (glyph_index);
}
};
struct hb_accelerate_subtables_context_t :
hb_dispatch_context_t<hb_accelerate_subtables_context_t>
{
template <typename Type>
static inline bool apply_to (const void *obj, OT::hb_ot_apply_context_t *c)
{
const Type *typed_obj = (const Type *) obj;
return typed_obj->apply (c);
}
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
template <typename T>
static inline auto apply_cached_ (const T *obj, OT::hb_ot_apply_context_t *c, hb_priority<1>) HB_RETURN (bool, obj->apply (c, true) )
template <typename T>
static inline auto apply_cached_ (const T *obj, OT::hb_ot_apply_context_t *c, hb_priority<0>) HB_RETURN (bool, obj->apply (c) )
template <typename Type>
static inline bool apply_cached_to (const void *obj, OT::hb_ot_apply_context_t *c)
{
const Type *typed_obj = (const Type *) obj;
return apply_cached_ (typed_obj, c, hb_prioritize);
}
template <typename T>
static inline auto cache_func_ (const T *obj, OT::hb_ot_apply_context_t *c, bool enter, hb_priority<1>) HB_RETURN (bool, obj->cache_func (c, enter) )
template <typename T>
static inline bool cache_func_ (const T *obj, OT::hb_ot_apply_context_t *c, bool enter, hb_priority<0>) { return false; }
template <typename Type>
static inline bool cache_func_to (const void *obj, OT::hb_ot_apply_context_t *c, bool enter)
{
const Type *typed_obj = (const Type *) obj;
return cache_func_ (typed_obj, c, enter, hb_prioritize);
}
#endif
typedef bool (*hb_apply_func_t) (const void *obj, OT::hb_ot_apply_context_t *c);
typedef bool (*hb_cache_func_t) (const void *obj, OT::hb_ot_apply_context_t *c, bool enter);
struct hb_applicable_t
{
friend struct hb_accelerate_subtables_context_t;
friend struct hb_ot_layout_lookup_accelerator_t;
template <typename T>
void init (const T &obj_,
hb_apply_func_t apply_func_
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
, hb_apply_func_t apply_cached_func_
, hb_cache_func_t cache_func_
#endif
)
{
obj = &obj_;
apply_func = apply_func_;
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
apply_cached_func = apply_cached_func_;
cache_func = cache_func_;
#endif
digest.init ();
obj_.get_coverage ().collect_coverage (&digest);
}
bool apply (OT::hb_ot_apply_context_t *c) const
{
return digest.may_have (c->buffer->cur().codepoint) && apply_func (obj, c);
}
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
bool apply_cached (OT::hb_ot_apply_context_t *c) const
{
return digest.may_have (c->buffer->cur().codepoint) && apply_cached_func (obj, c);
}
bool cache_enter (OT::hb_ot_apply_context_t *c) const
{
return cache_func (obj, c, true);
}
void cache_leave (OT::hb_ot_apply_context_t *c) const
{
cache_func (obj, c, false);
}
#endif
private:
const void *obj;
hb_apply_func_t apply_func;
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
hb_apply_func_t apply_cached_func;
hb_cache_func_t cache_func;
#endif
hb_set_digest_t digest;
};
typedef hb_vector_t<hb_applicable_t> array_t;
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
template <typename T>
auto cache_cost (const T &obj, hb_priority<1>) HB_AUTO_RETURN ( obj.cache_cost () )
template <typename T>
auto cache_cost (const T &obj, hb_priority<0>) HB_AUTO_RETURN ( 0u )
#endif
/* Dispatch interface. */
template <typename T>
return_t dispatch (const T &obj)
{
hb_applicable_t entry;
entry.init (obj,
apply_to<T>
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
, apply_cached_to<T>
, cache_func_to<T>
#endif
);
array.push (entry);
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
/* Cache handling
*
* We allow one subtable from each lookup to use a cache. The assumption
* being that multiple subtables of the same lookup cannot use a cache
* because the resources they would use will collide. As such, we ask
* each subtable to tell us how much it costs (which a cache would avoid),
* and we allocate the cache opportunity to the costliest subtable.
*/
unsigned cost = cache_cost (obj, hb_prioritize);
if (cost > cache_user_cost && !array.in_error ())
{
cache_user_idx = array.length - 1;
cache_user_cost = cost;
}
#endif
return hb_empty_t ();
}
static return_t default_return_value () { return hb_empty_t (); }
hb_accelerate_subtables_context_t (array_t &array_) :
array (array_) {}
array_t &array;
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
unsigned cache_user_idx = (unsigned) -1;
unsigned cache_user_cost = 0;
#endif
};
typedef bool (*intersects_func_t) (const hb_set_t *glyphs, unsigned value, const void *data);
typedef void (*intersected_glyphs_func_t) (const hb_set_t *glyphs, const void *data, unsigned value, hb_set_t *intersected_glyphs);
typedef void (*collect_glyphs_func_t) (hb_set_t *glyphs, unsigned value, const void *data);
typedef bool (*match_func_t) (hb_glyph_info_t &info, unsigned value, const void *data);
struct ContextClosureFuncs
{
intersects_func_t intersects;
intersected_glyphs_func_t intersected_glyphs;
};
struct ContextCollectGlyphsFuncs
{
collect_glyphs_func_t collect;
};
struct ContextApplyFuncs
{
match_func_t match;
};
struct ChainContextApplyFuncs
{
match_func_t match[3];
};
static inline bool intersects_glyph (const hb_set_t *glyphs, unsigned value, const void *data HB_UNUSED)
{
return glyphs->has (value);
}
static inline bool intersects_class (const hb_set_t *glyphs, unsigned value, const void *data)
{
const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data);
return class_def.intersects_class (glyphs, value);
}
static inline bool intersects_coverage (const hb_set_t *glyphs, unsigned value, const void *data)
{
Offset16To<Coverage> coverage;
coverage = value;
return (data+coverage).intersects (glyphs);
}
static inline void intersected_glyph (const hb_set_t *glyphs HB_UNUSED, const void *data, unsigned value, hb_set_t *intersected_glyphs)
{
unsigned g = reinterpret_cast<const HBUINT16 *>(data)[value];
intersected_glyphs->add (g);
}
static inline void intersected_class_glyphs (const hb_set_t *glyphs, const void *data, unsigned value, hb_set_t *intersected_glyphs)
{
const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data);
class_def.intersected_class_glyphs (glyphs, value, intersected_glyphs);
}
static inline void intersected_coverage_glyphs (const hb_set_t *glyphs, const void *data, unsigned value, hb_set_t *intersected_glyphs)
{
Offset16To<Coverage> coverage;
coverage = value;
(data+coverage).intersect_set (*glyphs, *intersected_glyphs);
}
template <typename HBUINT>
static inline bool array_is_subset_of (const hb_set_t *glyphs,
unsigned int count,
const HBUINT values[],
intersects_func_t intersects_func,
const void *intersects_data)
{
for (const auto &_ : + hb_iter (values, count))
if (!intersects_func (glyphs, _, intersects_data)) return false;
return true;
}
static inline void collect_glyph (hb_set_t *glyphs, unsigned value, const void *data HB_UNUSED)
{
glyphs->add (value);
}
static inline void collect_class (hb_set_t *glyphs, unsigned value, const void *data)
{
const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data);
class_def.collect_class (glyphs, value);
}
static inline void collect_coverage (hb_set_t *glyphs, unsigned value, const void *data)
{
Offset16To<Coverage> coverage;
coverage = value;
(data+coverage).collect_coverage (glyphs);
}
template <typename HBUINT>
static inline void collect_array (hb_collect_glyphs_context_t *c HB_UNUSED,
hb_set_t *glyphs,
unsigned int count,
const HBUINT values[],
collect_glyphs_func_t collect_func,
const void *collect_data)
{
return
+ hb_iter (values, count)
| hb_apply ([&] (const HBUINT &_) { collect_func (glyphs, _, collect_data); })
;
}
static inline bool match_glyph (hb_glyph_info_t &info, unsigned value, const void *data HB_UNUSED)
{
return info.codepoint == value;
}
static inline bool match_class (hb_glyph_info_t &info, unsigned value, const void *data)
{
const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data);
return class_def.get_class (info.codepoint) == value;
}
static inline bool match_class_cached (hb_glyph_info_t &info, unsigned value, const void *data)
{
unsigned klass = info.syllable();
if (klass < 255)
return klass == value;
const ClassDef &class_def = *reinterpret_cast<const ClassDef *>(data);
klass = class_def.get_class (info.codepoint);
if (likely (klass < 255))
info.syllable() = klass;
return klass == value;
}
static inline bool match_coverage (hb_glyph_info_t &info, unsigned value, const void *data)
{
Offset16To<Coverage> coverage;
coverage = value;
return (data+coverage).get_coverage (info.codepoint) != NOT_COVERED;
}
template <typename HBUINT>
static inline bool would_match_input (hb_would_apply_context_t *c,
unsigned int count, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
match_func_t match_func,
const void *match_data)
{
if (count != c->len)
return false;
for (unsigned int i = 1; i < count; i++)
{
hb_glyph_info_t info;
info.codepoint = c->glyphs[i];
if (likely (!match_func (info, input[i - 1], match_data)))
return false;
}
return true;
}
template <typename HBUINT>
static inline bool match_input (hb_ot_apply_context_t *c,
unsigned int count, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
match_func_t match_func,
const void *match_data,
unsigned int *end_position,
unsigned int match_positions[HB_MAX_CONTEXT_LENGTH],
unsigned int *p_total_component_count = nullptr)
{
TRACE_APPLY (nullptr);
if (unlikely (count > HB_MAX_CONTEXT_LENGTH)) return_trace (false);
hb_buffer_t *buffer = c->buffer;
hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input;
skippy_iter.reset (buffer->idx, count - 1);
skippy_iter.set_match_func (match_func, match_data);
skippy_iter.set_glyph_data (input);
/*
* This is perhaps the trickiest part of OpenType... Remarks:
*
* - If all components of the ligature were marks, we call this a mark ligature.
*
* - If there is no GDEF, and the ligature is NOT a mark ligature, we categorize
* it as a ligature glyph.
*
* - Ligatures cannot be formed across glyphs attached to different components
* of previous ligatures. Eg. the sequence is LAM,SHADDA,LAM,FATHA,HEH, and
* LAM,LAM,HEH form a ligature, leaving SHADDA,FATHA next to eachother.
* However, it would be wrong to ligate that SHADDA,FATHA sequence.
* There are a couple of exceptions to this:
*
* o If a ligature tries ligating with marks that belong to it itself, go ahead,
* assuming that the font designer knows what they are doing (otherwise it can
* break Indic stuff when a matra wants to ligate with a conjunct,
*
* o If two marks want to ligate and they belong to different components of the
* same ligature glyph, and said ligature glyph is to be ignored according to
* mark-filtering rules, then allow.
* https://github.com/harfbuzz/harfbuzz/issues/545
*/
unsigned int total_component_count = 0;
total_component_count += _hb_glyph_info_get_lig_num_comps (&buffer->cur());
unsigned int first_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur());
unsigned int first_lig_comp = _hb_glyph_info_get_lig_comp (&buffer->cur());
enum {
LIGBASE_NOT_CHECKED,
LIGBASE_MAY_NOT_SKIP,
LIGBASE_MAY_SKIP
} ligbase = LIGBASE_NOT_CHECKED;
match_positions[0] = buffer->idx;
for (unsigned int i = 1; i < count; i++)
{
unsigned unsafe_to;
if (!skippy_iter.next (&unsafe_to))
{
*end_position = unsafe_to;
return_trace (false);
}
match_positions[i] = skippy_iter.idx;
unsigned int this_lig_id = _hb_glyph_info_get_lig_id (&buffer->info[skippy_iter.idx]);
unsigned int this_lig_comp = _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx]);
if (first_lig_id && first_lig_comp)
{
/* If first component was attached to a previous ligature component,
* all subsequent components should be attached to the same ligature
* component, otherwise we shouldn't ligate them... */
if (first_lig_id != this_lig_id || first_lig_comp != this_lig_comp)
{
/* ...unless, we are attached to a base ligature and that base
* ligature is ignorable. */
if (ligbase == LIGBASE_NOT_CHECKED)
{
bool found = false;
const auto *out = buffer->out_info;
unsigned int j = buffer->out_len;
while (j && _hb_glyph_info_get_lig_id (&out[j - 1]) == first_lig_id)
{
if (_hb_glyph_info_get_lig_comp (&out[j - 1]) == 0)
{
j--;
found = true;
break;
}
j--;
}
if (found && skippy_iter.may_skip (out[j]) == hb_ot_apply_context_t::matcher_t::SKIP_YES)
ligbase = LIGBASE_MAY_SKIP;
else
ligbase = LIGBASE_MAY_NOT_SKIP;
}
if (ligbase == LIGBASE_MAY_NOT_SKIP)
return_trace (false);
}
}
else
{
/* If first component was NOT attached to a previous ligature component,
* all subsequent components should also NOT be attached to any ligature
* component, unless they are attached to the first component itself! */
if (this_lig_id && this_lig_comp && (this_lig_id != first_lig_id))
return_trace (false);
}
total_component_count += _hb_glyph_info_get_lig_num_comps (&buffer->info[skippy_iter.idx]);
}
*end_position = skippy_iter.idx + 1;
if (p_total_component_count)
*p_total_component_count = total_component_count;
return_trace (true);
}
static inline bool ligate_input (hb_ot_apply_context_t *c,
unsigned int count, /* Including the first glyph */
const unsigned int match_positions[HB_MAX_CONTEXT_LENGTH], /* Including the first glyph */
unsigned int match_end,
hb_codepoint_t lig_glyph,
unsigned int total_component_count)
{
TRACE_APPLY (nullptr);
hb_buffer_t *buffer = c->buffer;
buffer->merge_clusters (buffer->idx, match_end);
/* - If a base and one or more marks ligate, consider that as a base, NOT
* ligature, such that all following marks can still attach to it.
* https://github.com/harfbuzz/harfbuzz/issues/1109
*
* - If all components of the ligature were marks, we call this a mark ligature.
* If it *is* a mark ligature, we don't allocate a new ligature id, and leave
* the ligature to keep its old ligature id. This will allow it to attach to
* a base ligature in GPOS. Eg. if the sequence is: LAM,LAM,SHADDA,FATHA,HEH,
* and LAM,LAM,HEH for a ligature, they will leave SHADDA and FATHA with a
* ligature id and component value of 2. Then if SHADDA,FATHA form a ligature
* later, we don't want them to lose their ligature id/component, otherwise
* GPOS will fail to correctly position the mark ligature on top of the
* LAM,LAM,HEH ligature. See:
* https://bugzilla.gnome.org/show_bug.cgi?id=676343
*
* - If a ligature is formed of components that some of which are also ligatures
* themselves, and those ligature components had marks attached to *their*
* components, we have to attach the marks to the new ligature component
* positions! Now *that*'s tricky! And these marks may be following the
* last component of the whole sequence, so we should loop forward looking
* for them and update them.
*
* Eg. the sequence is LAM,LAM,SHADDA,FATHA,HEH, and the font first forms a
* 'calt' ligature of LAM,HEH, leaving the SHADDA and FATHA with a ligature
* id and component == 1. Now, during 'liga', the LAM and the LAM-HEH ligature
* form a LAM-LAM-HEH ligature. We need to reassign the SHADDA and FATHA to
* the new ligature with a component value of 2.
*
* This in fact happened to a font... See:
* https://bugzilla.gnome.org/show_bug.cgi?id=437633
*/
bool is_base_ligature = _hb_glyph_info_is_base_glyph (&buffer->info[match_positions[0]]);
bool is_mark_ligature = _hb_glyph_info_is_mark (&buffer->info[match_positions[0]]);
for (unsigned int i = 1; i < count; i++)
if (!_hb_glyph_info_is_mark (&buffer->info[match_positions[i]]))
{
is_base_ligature = false;
is_mark_ligature = false;
break;
}
bool is_ligature = !is_base_ligature && !is_mark_ligature;
unsigned int klass = is_ligature ? HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE : 0;
unsigned int lig_id = is_ligature ? _hb_allocate_lig_id (buffer) : 0;
unsigned int last_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur());
unsigned int last_num_components = _hb_glyph_info_get_lig_num_comps (&buffer->cur());
unsigned int components_so_far = last_num_components;
if (is_ligature)
{
_hb_glyph_info_set_lig_props_for_ligature (&buffer->cur(), lig_id, total_component_count);
if (_hb_glyph_info_get_general_category (&buffer->cur()) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK)
{
_hb_glyph_info_set_general_category (&buffer->cur(), HB_UNICODE_GENERAL_CATEGORY_OTHER_LETTER);
}
}
c->replace_glyph_with_ligature (lig_glyph, klass);
for (unsigned int i = 1; i < count; i++)
{
while (buffer->idx < match_positions[i] && buffer->successful)
{
if (is_ligature)
{
unsigned int this_comp = _hb_glyph_info_get_lig_comp (&buffer->cur());
if (this_comp == 0)
this_comp = last_num_components;
unsigned int new_lig_comp = components_so_far - last_num_components +
hb_min (this_comp, last_num_components);
_hb_glyph_info_set_lig_props_for_mark (&buffer->cur(), lig_id, new_lig_comp);
}
(void) buffer->next_glyph ();
}
last_lig_id = _hb_glyph_info_get_lig_id (&buffer->cur());
last_num_components = _hb_glyph_info_get_lig_num_comps (&buffer->cur());
components_so_far += last_num_components;
/* Skip the base glyph */
buffer->idx++;
}
if (!is_mark_ligature && last_lig_id)
{
/* Re-adjust components for any marks following. */
for (unsigned i = buffer->idx; i < buffer->len; ++i)
{
if (last_lig_id != _hb_glyph_info_get_lig_id (&buffer->info[i])) break;
unsigned this_comp = _hb_glyph_info_get_lig_comp (&buffer->info[i]);
if (!this_comp) break;
unsigned new_lig_comp = components_so_far - last_num_components +
hb_min (this_comp, last_num_components);
_hb_glyph_info_set_lig_props_for_mark (&buffer->info[i], lig_id, new_lig_comp);
}
}
return_trace (true);
}
template <typename HBUINT>
static inline bool match_backtrack (hb_ot_apply_context_t *c,
unsigned int count,
const HBUINT backtrack[],
match_func_t match_func,
const void *match_data,
unsigned int *match_start)
{
TRACE_APPLY (nullptr);
hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_context;
skippy_iter.reset (c->buffer->backtrack_len (), count);
skippy_iter.set_match_func (match_func, match_data);
skippy_iter.set_glyph_data (backtrack);
for (unsigned int i = 0; i < count; i++)
{
unsigned unsafe_from;
if (!skippy_iter.prev (&unsafe_from))
{
*match_start = unsafe_from;
return_trace (false);
}
}
*match_start = skippy_iter.idx;
return_trace (true);
}
template <typename HBUINT>
static inline bool match_lookahead (hb_ot_apply_context_t *c,
unsigned int count,
const HBUINT lookahead[],
match_func_t match_func,
const void *match_data,
unsigned int start_index,
unsigned int *end_index)
{
TRACE_APPLY (nullptr);
hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_context;
skippy_iter.reset (start_index - 1, count);
skippy_iter.set_match_func (match_func, match_data);
skippy_iter.set_glyph_data (lookahead);
for (unsigned int i = 0; i < count; i++)
{
unsigned unsafe_to;
if (!skippy_iter.next (&unsafe_to))
{
*end_index = unsafe_to;
return_trace (false);
}
}
*end_index = skippy_iter.idx + 1;
return_trace (true);
}
struct LookupRecord
{
bool serialize (hb_serialize_context_t *c,
const hb_map_t *lookup_map) const
{
TRACE_SERIALIZE (this);
auto *out = c->embed (*this);
if (unlikely (!out)) return_trace (false);
return_trace (c->check_assign (out->lookupListIndex, lookup_map->get (lookupListIndex), HB_SERIALIZE_ERROR_INT_OVERFLOW));
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this));
}
HBUINT16 sequenceIndex; /* Index into current glyph
* sequence--first glyph = 0 */
HBUINT16 lookupListIndex; /* Lookup to apply to that
* position--zero--based */
public:
DEFINE_SIZE_STATIC (4);
};
static unsigned serialize_lookuprecord_array (hb_serialize_context_t *c,
const hb_array_t<const LookupRecord> lookupRecords,
const hb_map_t *lookup_map)
{
unsigned count = 0;
for (const LookupRecord& r : lookupRecords)
{
if (!lookup_map->has (r.lookupListIndex))
continue;
if (!r.serialize (c, lookup_map))
return 0;
count++;
}
return count;
}
enum ContextFormat { SimpleContext = 1, ClassBasedContext = 2, CoverageBasedContext = 3 };
template <typename HBUINT>
static void context_closure_recurse_lookups (hb_closure_context_t *c,
unsigned inputCount, const HBUINT input[],
unsigned lookupCount,
const LookupRecord lookupRecord[] /* Array of LookupRecords--in design order */,
unsigned value,
ContextFormat context_format,
const void *data,
intersected_glyphs_func_t intersected_glyphs_func)
{
hb_set_t *covered_seq_indicies = hb_set_create ();
for (unsigned int i = 0; i < lookupCount; i++)
{
unsigned seqIndex = lookupRecord[i].sequenceIndex;
if (seqIndex >= inputCount) continue;
bool has_pos_glyphs = false;
hb_set_t pos_glyphs;
if (!hb_set_has (covered_seq_indicies, seqIndex))
{
has_pos_glyphs = true;
if (seqIndex == 0)
{
switch (context_format) {
case ContextFormat::SimpleContext:
pos_glyphs.add (value);
break;
case ContextFormat::ClassBasedContext:
intersected_glyphs_func (&c->parent_active_glyphs (), data, value, &pos_glyphs);
break;
case ContextFormat::CoverageBasedContext:
pos_glyphs.set (c->parent_active_glyphs ());
break;
}
}
else
{
const void *input_data = input;
unsigned input_value = seqIndex - 1;
if (context_format != ContextFormat::SimpleContext)
{
input_data = data;
input_value = input[seqIndex - 1];
}
intersected_glyphs_func (c->glyphs, input_data, input_value, &pos_glyphs);
}
}
covered_seq_indicies->add (seqIndex);
if (has_pos_glyphs) {
c->push_cur_active_glyphs () = std::move (pos_glyphs);
} else {
c->push_cur_active_glyphs ().set (*c->glyphs);
}
unsigned endIndex = inputCount;
if (context_format == ContextFormat::CoverageBasedContext)
endIndex += 1;
c->recurse (lookupRecord[i].lookupListIndex, covered_seq_indicies, seqIndex, endIndex);
c->pop_cur_done_glyphs ();
}
hb_set_destroy (covered_seq_indicies);
}
template <typename context_t>
static inline void recurse_lookups (context_t *c,
unsigned int lookupCount,
const LookupRecord lookupRecord[] /* Array of LookupRecords--in design order */)
{
for (unsigned int i = 0; i < lookupCount; i++)
c->recurse (lookupRecord[i].lookupListIndex);
}
static inline void apply_lookup (hb_ot_apply_context_t *c,
unsigned int count, /* Including the first glyph */
unsigned int match_positions[HB_MAX_CONTEXT_LENGTH], /* Including the first glyph */
unsigned int lookupCount,
const LookupRecord lookupRecord[], /* Array of LookupRecords--in design order */
unsigned int match_end)
{
hb_buffer_t *buffer = c->buffer;
int end;
/* All positions are distance from beginning of *output* buffer.
* Adjust. */
{
unsigned int bl = buffer->backtrack_len ();
end = bl + match_end - buffer->idx;
int delta = bl - buffer->idx;
/* Convert positions to new indexing. */
for (unsigned int j = 0; j < count; j++)
match_positions[j] += delta;
}
for (unsigned int i = 0; i < lookupCount && buffer->successful; i++)
{
unsigned int idx = lookupRecord[i].sequenceIndex;
if (idx >= count)
continue;
unsigned int orig_len = buffer->backtrack_len () + buffer->lookahead_len ();
/* This can happen if earlier recursed lookups deleted many entries. */
if (unlikely (match_positions[idx] >= orig_len))
continue;
if (unlikely (!buffer->move_to (match_positions[idx])))
break;
if (unlikely (buffer->max_ops <= 0))
break;
if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
{
if (buffer->have_output)
c->buffer->sync_so_far ();
c->buffer->message (c->font,
"recursing to lookup %u at %d",
(unsigned) lookupRecord[i].lookupListIndex,
buffer->idx);
}
if (!c->recurse (lookupRecord[i].lookupListIndex))
continue;
if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
{
if (buffer->have_output)
c->buffer->sync_so_far ();
c->buffer->message (c->font,
"recursed to lookup %u",
(unsigned) lookupRecord[i].lookupListIndex);
}
unsigned int new_len = buffer->backtrack_len () + buffer->lookahead_len ();
int delta = new_len - orig_len;
if (!delta)
continue;
/* Recursed lookup changed buffer len. Adjust.
*
* TODO:
*
* Right now, if buffer length increased by n, we assume n new glyphs
* were added right after the current position, and if buffer length
* was decreased by n, we assume n match positions after the current
* one where removed. The former (buffer length increased) case is
* fine, but the decrease case can be improved in at least two ways,
* both of which are significant:
*
* - If recursed-to lookup is MultipleSubst and buffer length
* decreased, then it's current match position that was deleted,
* NOT the one after it.
*
* - If buffer length was decreased by n, it does not necessarily
* mean that n match positions where removed, as there recursed-to
* lookup might had a different LookupFlag. Here's a constructed
* case of that:
* https://github.com/harfbuzz/harfbuzz/discussions/3538
*
* It should be possible to construct tests for both of these cases.
*/
end += delta;
if (end < int (match_positions[idx]))
{
/* End might end up being smaller than match_positions[idx] if the recursed
* lookup ended up removing many items.
* Just never rewind end beyond start of current position, since that is
* not possible in the recursed lookup. Also adjust delta as such.
*
* https://bugs.chromium.org/p/chromium/issues/detail?id=659496
* https://github.com/harfbuzz/harfbuzz/issues/1611
*/
delta += match_positions[idx] - end;
end = match_positions[idx];
}
unsigned int next = idx + 1; /* next now is the position after the recursed lookup. */
if (delta > 0)
{
if (unlikely (delta + count > HB_MAX_CONTEXT_LENGTH))
break;
}
else
{
/* NOTE: delta is non-positive. */
delta = hb_max (delta, (int) next - (int) count);
next -= delta;
}
/* Shift! */
memmove (match_positions + next + delta, match_positions + next,
(count - next) * sizeof (match_positions[0]));
next += delta;
count += delta;
/* Fill in new entries. */
for (unsigned int j = idx + 1; j < next; j++)
match_positions[j] = match_positions[j - 1] + 1;
/* And fixup the rest. */
for (; next < count; next++)
match_positions[next] += delta;
}
(void) buffer->move_to (end);
}
/* Contextual lookups */
struct ContextClosureLookupContext
{
ContextClosureFuncs funcs;
ContextFormat context_format;
const void *intersects_data;
};
struct ContextCollectGlyphsLookupContext
{
ContextCollectGlyphsFuncs funcs;
const void *collect_data;
};
struct ContextApplyLookupContext
{
ContextApplyFuncs funcs;
const void *match_data;
};
template <typename HBUINT>
static inline bool context_intersects (const hb_set_t *glyphs,
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
ContextClosureLookupContext &lookup_context)
{
return array_is_subset_of (glyphs,
inputCount ? inputCount - 1 : 0, input,
lookup_context.funcs.intersects, lookup_context.intersects_data);
}
template <typename HBUINT>
static inline void context_closure_lookup (hb_closure_context_t *c,
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
unsigned int lookupCount,
const LookupRecord lookupRecord[],
unsigned value, /* Index of first glyph in Coverage or Class value in ClassDef table */
ContextClosureLookupContext &lookup_context)
{
if (context_intersects (c->glyphs,
inputCount, input,
lookup_context))
context_closure_recurse_lookups (c,
inputCount, input,
lookupCount, lookupRecord,
value,
lookup_context.context_format,
lookup_context.intersects_data,
lookup_context.funcs.intersected_glyphs);
}
template <typename HBUINT>
static inline void context_collect_glyphs_lookup (hb_collect_glyphs_context_t *c,
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
unsigned int lookupCount,
const LookupRecord lookupRecord[],
ContextCollectGlyphsLookupContext &lookup_context)
{
collect_array (c, c->input,
inputCount ? inputCount - 1 : 0, input,
lookup_context.funcs.collect, lookup_context.collect_data);
recurse_lookups (c,
lookupCount, lookupRecord);
}
template <typename HBUINT>
static inline bool context_would_apply_lookup (hb_would_apply_context_t *c,
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
unsigned int lookupCount HB_UNUSED,
const LookupRecord lookupRecord[] HB_UNUSED,
ContextApplyLookupContext &lookup_context)
{
return would_match_input (c,
inputCount, input,
lookup_context.funcs.match, lookup_context.match_data);
}
template <typename HBUINT>
static inline bool context_apply_lookup (hb_ot_apply_context_t *c,
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
unsigned int lookupCount,
const LookupRecord lookupRecord[],
ContextApplyLookupContext &lookup_context)
{
unsigned match_end = 0;
unsigned match_positions[HB_MAX_CONTEXT_LENGTH];
if (match_input (c,
inputCount, input,
lookup_context.funcs.match, lookup_context.match_data,
&match_end, match_positions))
{
c->buffer->unsafe_to_break (c->buffer->idx, match_end);
apply_lookup (c,
inputCount, match_positions,
lookupCount, lookupRecord,
match_end);
return true;
}
else
{
c->buffer->unsafe_to_concat (c->buffer->idx, match_end);
return false;
}
}
template <typename Types>
struct Rule
{
bool intersects (const hb_set_t *glyphs, ContextClosureLookupContext &lookup_context) const
{
return context_intersects (glyphs,
inputCount, inputZ.arrayZ,
lookup_context);
}
void closure (hb_closure_context_t *c, unsigned value, ContextClosureLookupContext &lookup_context) const
{
if (unlikely (c->lookup_limit_exceeded ())) return;
const auto &lookupRecord = StructAfter<UnsizedArrayOf<LookupRecord>>
(inputZ.as_array ((inputCount ? inputCount - 1 : 0)));
context_closure_lookup (c,
inputCount, inputZ.arrayZ,
lookupCount, lookupRecord.arrayZ,
value, lookup_context);
}
void closure_lookups (hb_closure_lookups_context_t *c,
ContextClosureLookupContext &lookup_context) const
{
if (unlikely (c->lookup_limit_exceeded ())) return;
if (!intersects (c->glyphs, lookup_context)) return;
const auto &lookupRecord = StructAfter<UnsizedArrayOf<LookupRecord>>
(inputZ.as_array (inputCount ? inputCount - 1 : 0));
recurse_lookups (c, lookupCount, lookupRecord.arrayZ);
}
void collect_glyphs (hb_collect_glyphs_context_t *c,
ContextCollectGlyphsLookupContext &lookup_context) const
{
const auto &lookupRecord = StructAfter<UnsizedArrayOf<LookupRecord>>
(inputZ.as_array (inputCount ? inputCount - 1 : 0));
context_collect_glyphs_lookup (c,
inputCount, inputZ.arrayZ,
lookupCount, lookupRecord.arrayZ,
lookup_context);
}
bool would_apply (hb_would_apply_context_t *c,
ContextApplyLookupContext &lookup_context) const
{
const auto &lookupRecord = StructAfter<UnsizedArrayOf<LookupRecord>>
(inputZ.as_array (inputCount ? inputCount - 1 : 0));
return context_would_apply_lookup (c,
inputCount, inputZ.arrayZ,
lookupCount, lookupRecord.arrayZ,
lookup_context);
}
bool apply (hb_ot_apply_context_t *c,
ContextApplyLookupContext &lookup_context) const
{
TRACE_APPLY (this);
const auto &lookupRecord = StructAfter<UnsizedArrayOf<LookupRecord>>
(inputZ.as_array (inputCount ? inputCount - 1 : 0));
return_trace (context_apply_lookup (c, inputCount, inputZ.arrayZ, lookupCount, lookupRecord.arrayZ, lookup_context));
}
bool serialize (hb_serialize_context_t *c,
const hb_map_t *input_mapping, /* old->new glyphid or class mapping */
const hb_map_t *lookup_map) const
{
TRACE_SERIALIZE (this);
auto *out = c->start_embed (this);
if (unlikely (!c->extend_min (out))) return_trace (false);
out->inputCount = inputCount;
const auto input = inputZ.as_array (inputCount - 1);
for (const auto org : input)
{
HBUINT16 d;
d = input_mapping->get (org);
c->copy (d);
}
const auto &lookupRecord = StructAfter<UnsizedArrayOf<LookupRecord>>
(inputZ.as_array ((inputCount ? inputCount - 1 : 0)));
unsigned count = serialize_lookuprecord_array (c, lookupRecord.as_array (lookupCount), lookup_map);
return_trace (c->check_assign (out->lookupCount, count, HB_SERIALIZE_ERROR_INT_OVERFLOW));
}
bool subset (hb_subset_context_t *c,
const hb_map_t *lookup_map,
const hb_map_t *klass_map = nullptr) const
{
TRACE_SUBSET (this);
if (unlikely (!inputCount)) return_trace (false);
const auto input = inputZ.as_array (inputCount - 1);
const hb_map_t *mapping = klass_map == nullptr ? c->plan->glyph_map : klass_map;
if (!hb_all (input, mapping)) return_trace (false);
return_trace (serialize (c->serializer, mapping, lookup_map));
}
public:
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (inputCount.sanitize (c) &&
lookupCount.sanitize (c) &&
c->check_range (inputZ.arrayZ,
inputZ.item_size * (inputCount ? inputCount - 1 : 0) +
LookupRecord::static_size * lookupCount));
}
protected:
HBUINT16 inputCount; /* Total number of glyphs in input
* glyph sequence--includes the first
* glyph */
HBUINT16 lookupCount; /* Number of LookupRecords */
UnsizedArrayOf<typename Types::HBUINT>
inputZ; /* Array of match inputs--start with
* second glyph */
/*UnsizedArrayOf<LookupRecord>
lookupRecordX;*/ /* Array of LookupRecords--in
* design order */
public:
DEFINE_SIZE_ARRAY (4, inputZ);
};
template <typename Types>
struct RuleSet
{
using Rule = OT::Rule<Types>;
bool intersects (const hb_set_t *glyphs,
ContextClosureLookupContext &lookup_context) const
{
return
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_map ([&] (const Rule &_) { return _.intersects (glyphs, lookup_context); })
| hb_any
;
}
void closure (hb_closure_context_t *c, unsigned value,
ContextClosureLookupContext &lookup_context) const
{
if (unlikely (c->lookup_limit_exceeded ())) return;
return
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_apply ([&] (const Rule &_) { _.closure (c, value, lookup_context); })
;
}
void closure_lookups (hb_closure_lookups_context_t *c,
ContextClosureLookupContext &lookup_context) const
{
if (unlikely (c->lookup_limit_exceeded ())) return;
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_apply ([&] (const Rule &_) { _.closure_lookups (c, lookup_context); })
;
}
void collect_glyphs (hb_collect_glyphs_context_t *c,
ContextCollectGlyphsLookupContext &lookup_context) const
{
return
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_apply ([&] (const Rule &_) { _.collect_glyphs (c, lookup_context); })
;
}
bool would_apply (hb_would_apply_context_t *c,
ContextApplyLookupContext &lookup_context) const
{
return
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_map ([&] (const Rule &_) { return _.would_apply (c, lookup_context); })
| hb_any
;
}
bool apply (hb_ot_apply_context_t *c,
ContextApplyLookupContext &lookup_context) const
{
TRACE_APPLY (this);
return_trace (
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_map ([&] (const Rule &_) { return _.apply (c, lookup_context); })
| hb_any
)
;
}
bool subset (hb_subset_context_t *c,
const hb_map_t *lookup_map,
const hb_map_t *klass_map = nullptr) const
{
TRACE_SUBSET (this);
auto snap = c->serializer->snapshot ();
auto *out = c->serializer->start_embed (*this);
if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
for (const Offset16To<Rule>& _ : rule)
{
if (!_) continue;
auto o_snap = c->serializer->snapshot ();
auto *o = out->rule.serialize_append (c->serializer);
if (unlikely (!o)) continue;
if (!o->serialize_subset (c, _, this, lookup_map, klass_map))
{
out->rule.pop ();
c->serializer->revert (o_snap);
}
}
bool ret = bool (out->rule);
if (!ret) c->serializer->revert (snap);
return_trace (ret);
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (rule.sanitize (c, this));
}
protected:
Array16OfOffset16To<Rule>
rule; /* Array of Rule tables
* ordered by preference */
public:
DEFINE_SIZE_ARRAY (2, rule);
};
template <typename Types>
struct ContextFormat1_4
{
using RuleSet = OT::RuleSet<Types>;
bool intersects (const hb_set_t *glyphs) const
{
struct ContextClosureLookupContext lookup_context = {
{intersects_glyph, intersected_glyph},
ContextFormat::SimpleContext,
nullptr
};
return
+ hb_zip (this+coverage, ruleSet)
| hb_filter (*glyphs, hb_first)
| hb_map (hb_second)
| hb_map (hb_add (this))
| hb_map ([&] (const RuleSet &_) { return _.intersects (glyphs, lookup_context); })
| hb_any
;
}
bool may_have_non_1to1 () const
{ return true; }
void closure (hb_closure_context_t *c) const
{
hb_set_t& cur_active_glyphs = c->push_cur_active_glyphs ();
get_coverage ().intersect_set (c->previous_parent_active_glyphs (), cur_active_glyphs);
struct ContextClosureLookupContext lookup_context = {
{intersects_glyph, intersected_glyph},
ContextFormat::SimpleContext,
nullptr
};
+ hb_zip (this+coverage, hb_range ((unsigned) ruleSet.len))
| hb_filter ([&] (hb_codepoint_t _) {
return c->previous_parent_active_glyphs ().has (_);
}, hb_first)
| hb_map ([&](const hb_pair_t<hb_codepoint_t, unsigned> _) { return hb_pair_t<unsigned, const RuleSet&> (_.first, this+ruleSet[_.second]); })
| hb_apply ([&] (const hb_pair_t<unsigned, const RuleSet&>& _) { _.second.closure (c, _.first, lookup_context); })
;
c->pop_cur_done_glyphs ();
}
void closure_lookups (hb_closure_lookups_context_t *c) const
{
struct ContextClosureLookupContext lookup_context = {
{intersects_glyph, intersected_glyph},
ContextFormat::SimpleContext,
nullptr
};
+ hb_zip (this+coverage, ruleSet)
| hb_filter (*c->glyphs, hb_first)
| hb_map (hb_second)
| hb_map (hb_add (this))
| hb_apply ([&] (const RuleSet &_) { _.closure_lookups (c, lookup_context); })
;
}
void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {}
void collect_glyphs (hb_collect_glyphs_context_t *c) const
{
(this+coverage).collect_coverage (c->input);
struct ContextCollectGlyphsLookupContext lookup_context = {
{collect_glyph},
nullptr
};
+ hb_iter (ruleSet)
| hb_map (hb_add (this))
| hb_apply ([&] (const RuleSet &_) { _.collect_glyphs (c, lookup_context); })
;
}
bool would_apply (hb_would_apply_context_t *c) const
{
const RuleSet &rule_set = this+ruleSet[(this+coverage).get_coverage (c->glyphs[0])];
struct ContextApplyLookupContext lookup_context = {
{match_glyph},
nullptr
};
return rule_set.would_apply (c, lookup_context);
}
const Coverage &get_coverage () const { return this+coverage; }
bool apply (hb_ot_apply_context_t *c) const
{
TRACE_APPLY (this);
unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
if (likely (index == NOT_COVERED))
return_trace (false);
const RuleSet &rule_set = this+ruleSet[index];
struct ContextApplyLookupContext lookup_context = {
{match_glyph},
nullptr
};
return_trace (rule_set.apply (c, lookup_context));
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
const hb_map_t &glyph_map = *c->plan->glyph_map;
auto *out = c->serializer->start_embed (*this);
if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
out->format = format;
const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups;
hb_sorted_vector_t<hb_codepoint_t> new_coverage;
+ hb_zip (this+coverage, ruleSet)
| hb_filter (glyphset, hb_first)
| hb_filter (subset_offset_array (c, out->ruleSet, this, lookup_map), hb_second)
| hb_map (hb_first)
| hb_map (glyph_map)
| hb_sink (new_coverage)
;
out->coverage.serialize_serialize (c->serializer, new_coverage.iter ());
return_trace (bool (new_coverage));
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (coverage.sanitize (c, this) && ruleSet.sanitize (c, this));
}
protected:
HBUINT16 format; /* Format identifier--format = 1 */
typename Types::template OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of table */
Array16Of<typename Types::template OffsetTo<RuleSet>>
ruleSet; /* Array of RuleSet tables
* ordered by Coverage Index */
public:
DEFINE_SIZE_ARRAY (2 + 2 * Types::size, ruleSet);
};
template <typename Types>
struct ContextFormat2_5
{
using RuleSet = OT::RuleSet<SmallTypes>;
bool intersects (const hb_set_t *glyphs) const
{
if (!(this+coverage).intersects (glyphs))
return false;
const ClassDef &class_def = this+classDef;
struct ContextClosureLookupContext lookup_context = {
{intersects_class, intersected_class_glyphs},
ContextFormat::ClassBasedContext,
&class_def
};
hb_set_t retained_coverage_glyphs;
(this+coverage).intersect_set (*glyphs, retained_coverage_glyphs);
hb_set_t coverage_glyph_classes;
class_def.intersected_classes (&retained_coverage_glyphs, &coverage_glyph_classes);
return
+ hb_iter (ruleSet)
| hb_map (hb_add (this))
| hb_enumerate
| hb_map ([&] (const hb_pair_t<unsigned, const RuleSet &> p)
{ return class_def.intersects_class (glyphs, p.first) &&
coverage_glyph_classes.has (p.first) &&
p.second.intersects (glyphs, lookup_context); })
| hb_any
;
}
bool may_have_non_1to1 () const
{ return true; }
void closure (hb_closure_context_t *c) const
{
if (!(this+coverage).intersects (c->glyphs))
return;
hb_set_t& cur_active_glyphs = c->push_cur_active_glyphs ();
get_coverage ().intersect_set (c->previous_parent_active_glyphs (),
cur_active_glyphs);
const ClassDef &class_def = this+classDef;
struct ContextClosureLookupContext lookup_context = {
{intersects_class, intersected_class_glyphs},
ContextFormat::ClassBasedContext,
&class_def
};
+ hb_enumerate (ruleSet)
| hb_filter ([&] (unsigned _)
{ return class_def.intersects_class (&c->parent_active_glyphs (), _); },
hb_first)
| hb_apply ([&] (const hb_pair_t<unsigned, const typename Types::template OffsetTo<RuleSet>&> _)
{
const RuleSet& rule_set = this+_.second;
rule_set.closure (c, _.first, lookup_context);
})
;
c->pop_cur_done_glyphs ();
}
void closure_lookups (hb_closure_lookups_context_t *c) const
{
if (!(this+coverage).intersects (c->glyphs))
return;
const ClassDef &class_def = this+classDef;
struct ContextClosureLookupContext lookup_context = {
{intersects_class, intersected_class_glyphs},
ContextFormat::ClassBasedContext,
&class_def
};
+ hb_iter (ruleSet)
| hb_map (hb_add (this))
| hb_enumerate
| hb_filter ([&] (const hb_pair_t<unsigned, const RuleSet &> p)
{ return class_def.intersects_class (c->glyphs, p.first); })
| hb_map (hb_second)
| hb_apply ([&] (const RuleSet & _)
{ _.closure_lookups (c, lookup_context); });
}
void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {}
void collect_glyphs (hb_collect_glyphs_context_t *c) const
{
(this+coverage).collect_coverage (c->input);
const ClassDef &class_def = this+classDef;
struct ContextCollectGlyphsLookupContext lookup_context = {
{collect_class},
&class_def
};
+ hb_iter (ruleSet)
| hb_map (hb_add (this))
| hb_apply ([&] (const RuleSet &_) { _.collect_glyphs (c, lookup_context); })
;
}
bool would_apply (hb_would_apply_context_t *c) const
{
const ClassDef &class_def = this+classDef;
unsigned int index = class_def.get_class (c->glyphs[0]);
const RuleSet &rule_set = this+ruleSet[index];
struct ContextApplyLookupContext lookup_context = {
{match_class},
&class_def
};
return rule_set.would_apply (c, lookup_context);
}
const Coverage &get_coverage () const { return this+coverage; }
unsigned cache_cost () const
{
unsigned c = (this+classDef).cost () * ruleSet.len;
return c >= 4 ? c : 0;
}
bool cache_func (hb_ot_apply_context_t *c, bool enter) const
{
if (enter)
{
if (!HB_BUFFER_TRY_ALLOCATE_VAR (c->buffer, syllable))
return false;
auto &info = c->buffer->info;
unsigned count = c->buffer->len;
for (unsigned i = 0; i < count; i++)
info[i].syllable() = 255;
c->new_syllables = 255;
return true;
}
else
{
c->new_syllables = (unsigned) -1;
HB_BUFFER_DEALLOCATE_VAR (c->buffer, syllable);
return true;
}
}
bool apply (hb_ot_apply_context_t *c, bool cached = false) const
{
TRACE_APPLY (this);
unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
if (likely (index == NOT_COVERED)) return_trace (false);
const ClassDef &class_def = this+classDef;
struct ContextApplyLookupContext lookup_context = {
{cached ? match_class_cached : match_class},
&class_def
};
if (cached && c->buffer->cur().syllable() < 255)
index = c->buffer->cur().syllable ();
else
{
index = class_def.get_class (c->buffer->cur().codepoint);
if (cached && index < 255)
c->buffer->cur().syllable() = index;
}
const RuleSet &rule_set = this+ruleSet[index];
return_trace (rule_set.apply (c, lookup_context));
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
auto *out = c->serializer->start_embed (*this);
if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
out->format = format;
if (unlikely (!out->coverage.serialize_subset (c, coverage, this)))
return_trace (false);
hb_map_t klass_map;
out->classDef.serialize_subset (c, classDef, this, &klass_map);
const hb_set_t* glyphset = c->plan->glyphset_gsub ();
hb_set_t retained_coverage_glyphs;
(this+coverage).intersect_set (*glyphset, retained_coverage_glyphs);
hb_set_t coverage_glyph_classes;
(this+classDef).intersected_classes (&retained_coverage_glyphs, &coverage_glyph_classes);
const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups;
bool ret = true;
int non_zero_index = -1, index = 0;
for (const auto& _ : + hb_enumerate (ruleSet)
| hb_filter (klass_map, hb_first))
{
auto *o = out->ruleSet.serialize_append (c->serializer);
if (unlikely (!o))
{
ret = false;
break;
}
if (coverage_glyph_classes.has (_.first) &&
o->serialize_subset (c, _.second, this, lookup_map, &klass_map))
non_zero_index = index;
index++;
}
if (!ret || non_zero_index == -1) return_trace (false);
//prune empty trailing ruleSets
--index;
while (index > non_zero_index)
{
out->ruleSet.pop ();
index--;
}
return_trace (bool (out->ruleSet));
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (coverage.sanitize (c, this) && classDef.sanitize (c, this) && ruleSet.sanitize (c, this));
}
protected:
HBUINT16 format; /* Format identifier--format = 2 */
typename Types::template OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of table */
typename Types::template OffsetTo<ClassDef>
classDef; /* Offset to glyph ClassDef table--from
* beginning of table */
Array16Of<typename Types::template OffsetTo<RuleSet>>
ruleSet; /* Array of RuleSet tables
* ordered by class */
public:
DEFINE_SIZE_ARRAY (4 + 2 * Types::size, ruleSet);
};
struct ContextFormat3
{
using RuleSet = OT::RuleSet<SmallTypes>;
bool intersects (const hb_set_t *glyphs) const
{
if (!(this+coverageZ[0]).intersects (glyphs))
return false;
struct ContextClosureLookupContext lookup_context = {
{intersects_coverage, intersected_coverage_glyphs},
ContextFormat::CoverageBasedContext,
this
};
return context_intersects (glyphs,
glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1),
lookup_context);
}
bool may_have_non_1to1 () const
{ return true; }
void closure (hb_closure_context_t *c) const
{
if (!(this+coverageZ[0]).intersects (c->glyphs))
return;
hb_set_t& cur_active_glyphs = c->push_cur_active_glyphs ();
get_coverage ().intersect_set (c->previous_parent_active_glyphs (),
cur_active_glyphs);
const LookupRecord *lookupRecord = &StructAfter<LookupRecord> (coverageZ.as_array (glyphCount));
struct ContextClosureLookupContext lookup_context = {
{intersects_coverage, intersected_coverage_glyphs},
ContextFormat::CoverageBasedContext,
this
};
context_closure_lookup (c,
glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1),
lookupCount, lookupRecord,
0, lookup_context);
c->pop_cur_done_glyphs ();
}
void closure_lookups (hb_closure_lookups_context_t *c) const
{
if (!intersects (c->glyphs))
return;
const LookupRecord *lookupRecord = &StructAfter<LookupRecord> (coverageZ.as_array (glyphCount));
recurse_lookups (c, lookupCount, lookupRecord);
}
void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {}
void collect_glyphs (hb_collect_glyphs_context_t *c) const
{
(this+coverageZ[0]).collect_coverage (c->input);
const LookupRecord *lookupRecord = &StructAfter<LookupRecord> (coverageZ.as_array (glyphCount));
struct ContextCollectGlyphsLookupContext lookup_context = {
{collect_coverage},
this
};
context_collect_glyphs_lookup (c,
glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1),
lookupCount, lookupRecord,
lookup_context);
}
bool would_apply (hb_would_apply_context_t *c) const
{
const LookupRecord *lookupRecord = &StructAfter<LookupRecord> (coverageZ.as_array (glyphCount));
struct ContextApplyLookupContext lookup_context = {
{match_coverage},
this
};
return context_would_apply_lookup (c,
glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1),
lookupCount, lookupRecord,
lookup_context);
}
const Coverage &get_coverage () const { return this+coverageZ[0]; }
bool apply (hb_ot_apply_context_t *c) const
{
TRACE_APPLY (this);
unsigned int index = (this+coverageZ[0]).get_coverage (c->buffer->cur().codepoint);
if (likely (index == NOT_COVERED)) return_trace (false);
const LookupRecord *lookupRecord = &StructAfter<LookupRecord> (coverageZ.as_array (glyphCount));
struct ContextApplyLookupContext lookup_context = {
{match_coverage},
this
};
return_trace (context_apply_lookup (c, glyphCount, (const HBUINT16 *) (coverageZ.arrayZ + 1), lookupCount, lookupRecord, lookup_context));
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
auto *out = c->serializer->start_embed (this);
if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
out->format = format;
out->glyphCount = glyphCount;
auto coverages = coverageZ.as_array (glyphCount);
for (const Offset16To<Coverage>& offset : coverages)
{
/* TODO(subset) This looks like should not be necessary to write this way. */
auto *o = c->serializer->allocate_size<Offset16To<Coverage>> (Offset16To<Coverage>::static_size);
if (unlikely (!o)) return_trace (false);
if (!o->serialize_subset (c, offset, this)) return_trace (false);
}
const auto& lookupRecord = StructAfter<UnsizedArrayOf<LookupRecord>> (coverageZ.as_array (glyphCount));
const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups;
unsigned count = serialize_lookuprecord_array (c->serializer, lookupRecord.as_array (lookupCount), lookup_map);
return_trace (c->serializer->check_assign (out->lookupCount, count, HB_SERIALIZE_ERROR_INT_OVERFLOW));
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (!c->check_struct (this)) return_trace (false);
unsigned int count = glyphCount;
if (!count) return_trace (false); /* We want to access coverageZ[0] freely. */
if (!c->check_array (coverageZ.arrayZ, count)) return_trace (false);
for (unsigned int i = 0; i < count; i++)
if (!coverageZ[i].sanitize (c, this)) return_trace (false);
const LookupRecord *lookupRecord = &StructAfter<LookupRecord> (coverageZ.as_array (glyphCount));
return_trace (c->check_array (lookupRecord, lookupCount));
}
protected:
HBUINT16 format; /* Format identifier--format = 3 */
HBUINT16 glyphCount; /* Number of glyphs in the input glyph
* sequence */
HBUINT16 lookupCount; /* Number of LookupRecords */
UnsizedArrayOf<Offset16To<Coverage>>
coverageZ; /* Array of offsets to Coverage
* table in glyph sequence order */
/*UnsizedArrayOf<LookupRecord>
lookupRecordX;*/ /* Array of LookupRecords--in
* design order */
public:
DEFINE_SIZE_ARRAY (6, coverageZ);
};
struct Context
{
template <typename context_t, typename ...Ts>
typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
{
TRACE_DISPATCH (this, u.format);
if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ());
switch (u.format) {
case 1: return_trace (c->dispatch (u.format1, std::forward<Ts> (ds)...));
case 2: return_trace (c->dispatch (u.format2, std::forward<Ts> (ds)...));
case 3: return_trace (c->dispatch (u.format3, std::forward<Ts> (ds)...));
#ifndef HB_NO_BEYOND_64K
case 4: return_trace (c->dispatch (u.format4, std::forward<Ts> (ds)...));
case 5: return_trace (c->dispatch (u.format5, std::forward<Ts> (ds)...));
#endif
default:return_trace (c->default_return_value ());
}
}
protected:
union {
HBUINT16 format; /* Format identifier */
ContextFormat1_4<SmallTypes> format1;
ContextFormat2_5<SmallTypes> format2;
ContextFormat3 format3;
#ifndef HB_NO_BEYOND_64K
ContextFormat1_4<MediumTypes> format4;
ContextFormat2_5<MediumTypes> format5;
#endif
} u;
};
/* Chaining Contextual lookups */
struct ChainContextClosureLookupContext
{
ContextClosureFuncs funcs;
ContextFormat context_format;
const void *intersects_data[3];
};
struct ChainContextCollectGlyphsLookupContext
{
ContextCollectGlyphsFuncs funcs;
const void *collect_data[3];
};
struct ChainContextApplyLookupContext
{
ChainContextApplyFuncs funcs;
const void *match_data[3];
};
template <typename HBUINT>
static inline bool chain_context_intersects (const hb_set_t *glyphs,
unsigned int backtrackCount,
const HBUINT backtrack[],
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
unsigned int lookaheadCount,
const HBUINT lookahead[],
ChainContextClosureLookupContext &lookup_context)
{
return array_is_subset_of (glyphs,
backtrackCount, backtrack,
lookup_context.funcs.intersects, lookup_context.intersects_data[0])
&& array_is_subset_of (glyphs,
inputCount ? inputCount - 1 : 0, input,
lookup_context.funcs.intersects, lookup_context.intersects_data[1])
&& array_is_subset_of (glyphs,
lookaheadCount, lookahead,
lookup_context.funcs.intersects, lookup_context.intersects_data[2]);
}
template <typename HBUINT>
static inline void chain_context_closure_lookup (hb_closure_context_t *c,
unsigned int backtrackCount,
const HBUINT backtrack[],
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
unsigned int lookaheadCount,
const HBUINT lookahead[],
unsigned int lookupCount,
const LookupRecord lookupRecord[],
unsigned value,
ChainContextClosureLookupContext &lookup_context)
{
if (chain_context_intersects (c->glyphs,
backtrackCount, backtrack,
inputCount, input,
lookaheadCount, lookahead,
lookup_context))
context_closure_recurse_lookups (c,
inputCount, input,
lookupCount, lookupRecord,
value,
lookup_context.context_format,
lookup_context.intersects_data[1],
lookup_context.funcs.intersected_glyphs);
}
template <typename HBUINT>
static inline void chain_context_collect_glyphs_lookup (hb_collect_glyphs_context_t *c,
unsigned int backtrackCount,
const HBUINT backtrack[],
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
unsigned int lookaheadCount,
const HBUINT lookahead[],
unsigned int lookupCount,
const LookupRecord lookupRecord[],
ChainContextCollectGlyphsLookupContext &lookup_context)
{
collect_array (c, c->before,
backtrackCount, backtrack,
lookup_context.funcs.collect, lookup_context.collect_data[0]);
collect_array (c, c->input,
inputCount ? inputCount - 1 : 0, input,
lookup_context.funcs.collect, lookup_context.collect_data[1]);
collect_array (c, c->after,
lookaheadCount, lookahead,
lookup_context.funcs.collect, lookup_context.collect_data[2]);
recurse_lookups (c,
lookupCount, lookupRecord);
}
template <typename HBUINT>
static inline bool chain_context_would_apply_lookup (hb_would_apply_context_t *c,
unsigned int backtrackCount,
const HBUINT backtrack[] HB_UNUSED,
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
unsigned int lookaheadCount,
const HBUINT lookahead[] HB_UNUSED,
unsigned int lookupCount HB_UNUSED,
const LookupRecord lookupRecord[] HB_UNUSED,
ChainContextApplyLookupContext &lookup_context)
{
return (c->zero_context ? !backtrackCount && !lookaheadCount : true)
&& would_match_input (c,
inputCount, input,
lookup_context.funcs.match[1], lookup_context.match_data[1]);
}
template <typename HBUINT>
static inline bool chain_context_apply_lookup (hb_ot_apply_context_t *c,
unsigned int backtrackCount,
const HBUINT backtrack[],
unsigned int inputCount, /* Including the first glyph (not matched) */
const HBUINT input[], /* Array of input values--start with second glyph */
unsigned int lookaheadCount,
const HBUINT lookahead[],
unsigned int lookupCount,
const LookupRecord lookupRecord[],
ChainContextApplyLookupContext &lookup_context)
{
unsigned end_index = c->buffer->idx;
unsigned match_end = 0;
unsigned match_positions[HB_MAX_CONTEXT_LENGTH];
if (!(match_input (c,
inputCount, input,
lookup_context.funcs.match[1], lookup_context.match_data[1],
&match_end, match_positions) && (end_index = match_end)
&& match_lookahead (c,
lookaheadCount, lookahead,
lookup_context.funcs.match[2], lookup_context.match_data[2],
match_end, &end_index)))
{
c->buffer->unsafe_to_concat (c->buffer->idx, end_index);
return false;
}
unsigned start_index = c->buffer->out_len;
if (!match_backtrack (c,
backtrackCount, backtrack,
lookup_context.funcs.match[0], lookup_context.match_data[0],
&start_index))
{
c->buffer->unsafe_to_concat_from_outbuffer (start_index, end_index);
return false;
}
c->buffer->unsafe_to_break_from_outbuffer (start_index, end_index);
apply_lookup (c,
inputCount, match_positions,
lookupCount, lookupRecord,
match_end);
return true;
}
template <typename Types>
struct ChainRule
{
bool intersects (const hb_set_t *glyphs, ChainContextClosureLookupContext &lookup_context) const
{
const auto &input = StructAfter<decltype (inputX)> (backtrack);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
return chain_context_intersects (glyphs,
backtrack.len, backtrack.arrayZ,
input.lenP1, input.arrayZ,
lookahead.len, lookahead.arrayZ,
lookup_context);
}
void closure (hb_closure_context_t *c, unsigned value,
ChainContextClosureLookupContext &lookup_context) const
{
if (unlikely (c->lookup_limit_exceeded ())) return;
const auto &input = StructAfter<decltype (inputX)> (backtrack);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
chain_context_closure_lookup (c,
backtrack.len, backtrack.arrayZ,
input.lenP1, input.arrayZ,
lookahead.len, lookahead.arrayZ,
lookup.len, lookup.arrayZ,
value,
lookup_context);
}
void closure_lookups (hb_closure_lookups_context_t *c,
ChainContextClosureLookupContext &lookup_context) const
{
if (unlikely (c->lookup_limit_exceeded ())) return;
if (!intersects (c->glyphs, lookup_context)) return;
const auto &input = StructAfter<decltype (inputX)> (backtrack);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
recurse_lookups (c, lookup.len, lookup.arrayZ);
}
void collect_glyphs (hb_collect_glyphs_context_t *c,
ChainContextCollectGlyphsLookupContext &lookup_context) const
{
const auto &input = StructAfter<decltype (inputX)> (backtrack);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
chain_context_collect_glyphs_lookup (c,
backtrack.len, backtrack.arrayZ,
input.lenP1, input.arrayZ,
lookahead.len, lookahead.arrayZ,
lookup.len, lookup.arrayZ,
lookup_context);
}
bool would_apply (hb_would_apply_context_t *c,
ChainContextApplyLookupContext &lookup_context) const
{
const auto &input = StructAfter<decltype (inputX)> (backtrack);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
return chain_context_would_apply_lookup (c,
backtrack.len, backtrack.arrayZ,
input.lenP1, input.arrayZ,
lookahead.len, lookahead.arrayZ, lookup.len,
lookup.arrayZ, lookup_context);
}
bool apply (hb_ot_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const
{
TRACE_APPLY (this);
const auto &input = StructAfter<decltype (inputX)> (backtrack);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
return_trace (chain_context_apply_lookup (c,
backtrack.len, backtrack.arrayZ,
input.lenP1, input.arrayZ,
lookahead.len, lookahead.arrayZ, lookup.len,
lookup.arrayZ, lookup_context));
}
template<typename Iterator,
hb_requires (hb_is_iterator (Iterator))>
void serialize_array (hb_serialize_context_t *c,
HBUINT16 len,
Iterator it) const
{
c->copy (len);
for (const auto g : it)
c->copy ((HBUINT16) g);
}
bool serialize (hb_serialize_context_t *c,
const hb_map_t *lookup_map,
const hb_map_t *backtrack_map,
const hb_map_t *input_map = nullptr,
const hb_map_t *lookahead_map = nullptr) const
{
TRACE_SERIALIZE (this);
auto *out = c->start_embed (this);
if (unlikely (!out)) return_trace (false);
const hb_map_t *mapping = backtrack_map;
serialize_array (c, backtrack.len, + backtrack.iter ()
| hb_map (mapping));
const auto &input = StructAfter<decltype (inputX)> (backtrack);
if (input_map) mapping = input_map;
serialize_array (c, input.lenP1, + input.iter ()
| hb_map (mapping));
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
if (lookahead_map) mapping = lookahead_map;
serialize_array (c, lookahead.len, + lookahead.iter ()
| hb_map (mapping));
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
HBUINT16* lookupCount = c->embed (&(lookup.len));
if (!lookupCount) return_trace (false);
unsigned count = serialize_lookuprecord_array (c, lookup.as_array (), lookup_map);
return_trace (c->check_assign (*lookupCount, count, HB_SERIALIZE_ERROR_INT_OVERFLOW));
}
bool subset (hb_subset_context_t *c,
const hb_map_t *lookup_map,
const hb_map_t *backtrack_map = nullptr,
const hb_map_t *input_map = nullptr,
const hb_map_t *lookahead_map = nullptr) const
{
TRACE_SUBSET (this);
const auto &input = StructAfter<decltype (inputX)> (backtrack);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
if (!backtrack_map)
{
const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
if (!hb_all (backtrack, glyphset) ||
!hb_all (input, glyphset) ||
!hb_all (lookahead, glyphset))
return_trace (false);
serialize (c->serializer, lookup_map, c->plan->glyph_map);
}
else
{
if (!hb_all (backtrack, backtrack_map) ||
!hb_all (input, input_map) ||
!hb_all (lookahead, lookahead_map))
return_trace (false);
serialize (c->serializer, lookup_map, backtrack_map, input_map, lookahead_map);
}
return_trace (true);
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (!backtrack.sanitize (c)) return_trace (false);
const auto &input = StructAfter<decltype (inputX)> (backtrack);
if (!input.sanitize (c)) return_trace (false);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
if (!lookahead.sanitize (c)) return_trace (false);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
return_trace (lookup.sanitize (c));
}
protected:
Array16Of<typename Types::HBUINT>
backtrack; /* Array of backtracking values
* (to be matched before the input
* sequence) */
HeadlessArrayOf<typename Types::HBUINT>
inputX; /* Array of input values (start with
* second glyph) */
Array16Of<typename Types::HBUINT>
lookaheadX; /* Array of lookahead values's (to be
* matched after the input sequence) */
Array16Of<LookupRecord>
lookupX; /* Array of LookupRecords--in
* design order) */
public:
DEFINE_SIZE_MIN (8);
};
template <typename Types>
struct ChainRuleSet
{
using ChainRule = OT::ChainRule<Types>;
bool intersects (const hb_set_t *glyphs, ChainContextClosureLookupContext &lookup_context) const
{
return
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_map ([&] (const ChainRule &_) { return _.intersects (glyphs, lookup_context); })
| hb_any
;
}
void closure (hb_closure_context_t *c, unsigned value, ChainContextClosureLookupContext &lookup_context) const
{
if (unlikely (c->lookup_limit_exceeded ())) return;
return
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_apply ([&] (const ChainRule &_) { _.closure (c, value, lookup_context); })
;
}
void closure_lookups (hb_closure_lookups_context_t *c,
ChainContextClosureLookupContext &lookup_context) const
{
if (unlikely (c->lookup_limit_exceeded ())) return;
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_apply ([&] (const ChainRule &_) { _.closure_lookups (c, lookup_context); })
;
}
void collect_glyphs (hb_collect_glyphs_context_t *c, ChainContextCollectGlyphsLookupContext &lookup_context) const
{
return
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_apply ([&] (const ChainRule &_) { _.collect_glyphs (c, lookup_context); })
;
}
bool would_apply (hb_would_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const
{
return
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_map ([&] (const ChainRule &_) { return _.would_apply (c, lookup_context); })
| hb_any
;
}
bool apply (hb_ot_apply_context_t *c, ChainContextApplyLookupContext &lookup_context) const
{
TRACE_APPLY (this);
return_trace (
+ hb_iter (rule)
| hb_map (hb_add (this))
| hb_map ([&] (const ChainRule &_) { return _.apply (c, lookup_context); })
| hb_any
)
;
}
bool subset (hb_subset_context_t *c,
const hb_map_t *lookup_map,
const hb_map_t *backtrack_klass_map = nullptr,
const hb_map_t *input_klass_map = nullptr,
const hb_map_t *lookahead_klass_map = nullptr) const
{
TRACE_SUBSET (this);
auto snap = c->serializer->snapshot ();
auto *out = c->serializer->start_embed (*this);
if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
for (const Offset16To<ChainRule>& _ : rule)
{
if (!_) continue;
auto o_snap = c->serializer->snapshot ();
auto *o = out->rule.serialize_append (c->serializer);
if (unlikely (!o)) continue;
if (!o->serialize_subset (c, _, this,
lookup_map,
backtrack_klass_map,
input_klass_map,
lookahead_klass_map))
{
out->rule.pop ();
c->serializer->revert (o_snap);
}
}
bool ret = bool (out->rule);
if (!ret) c->serializer->revert (snap);
return_trace (ret);
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (rule.sanitize (c, this));
}
protected:
Array16OfOffset16To<ChainRule>
rule; /* Array of ChainRule tables
* ordered by preference */
public:
DEFINE_SIZE_ARRAY (2, rule);
};
template <typename Types>
struct ChainContextFormat1_4
{
using ChainRuleSet = OT::ChainRuleSet<Types>;
bool intersects (const hb_set_t *glyphs) const
{
struct ChainContextClosureLookupContext lookup_context = {
{intersects_glyph, intersected_glyph},
ContextFormat::SimpleContext,
{nullptr, nullptr, nullptr}
};
return
+ hb_zip (this+coverage, ruleSet)
| hb_filter (*glyphs, hb_first)
| hb_map (hb_second)
| hb_map (hb_add (this))
| hb_map ([&] (const ChainRuleSet &_) { return _.intersects (glyphs, lookup_context); })
| hb_any
;
}
bool may_have_non_1to1 () const
{ return true; }
void closure (hb_closure_context_t *c) const
{
hb_set_t& cur_active_glyphs = c->push_cur_active_glyphs ();
get_coverage ().intersect_set (c->previous_parent_active_glyphs (),
cur_active_glyphs);
struct ChainContextClosureLookupContext lookup_context = {
{intersects_glyph, intersected_glyph},
ContextFormat::SimpleContext,
{nullptr, nullptr, nullptr}
};
+ hb_zip (this+coverage, hb_range ((unsigned) ruleSet.len))
| hb_filter ([&] (hb_codepoint_t _) {
return c->previous_parent_active_glyphs ().has (_);
}, hb_first)
| hb_map ([&](const hb_pair_t<hb_codepoint_t, unsigned> _) { return hb_pair_t<unsigned, const ChainRuleSet&> (_.first, this+ruleSet[_.second]); })
| hb_apply ([&] (const hb_pair_t<unsigned, const ChainRuleSet&>& _) { _.second.closure (c, _.first, lookup_context); })
;
c->pop_cur_done_glyphs ();
}
void closure_lookups (hb_closure_lookups_context_t *c) const
{
struct ChainContextClosureLookupContext lookup_context = {
{intersects_glyph, intersected_glyph},
ContextFormat::SimpleContext,
{nullptr, nullptr, nullptr}
};
+ hb_zip (this+coverage, ruleSet)
| hb_filter (*c->glyphs, hb_first)
| hb_map (hb_second)
| hb_map (hb_add (this))
| hb_apply ([&] (const ChainRuleSet &_) { _.closure_lookups (c, lookup_context); })
;
}
void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {}
void collect_glyphs (hb_collect_glyphs_context_t *c) const
{
(this+coverage).collect_coverage (c->input);
struct ChainContextCollectGlyphsLookupContext lookup_context = {
{collect_glyph},
{nullptr, nullptr, nullptr}
};
+ hb_iter (ruleSet)
| hb_map (hb_add (this))
| hb_apply ([&] (const ChainRuleSet &_) { _.collect_glyphs (c, lookup_context); })
;
}
bool would_apply (hb_would_apply_context_t *c) const
{
const ChainRuleSet &rule_set = this+ruleSet[(this+coverage).get_coverage (c->glyphs[0])];
struct ChainContextApplyLookupContext lookup_context = {
{{match_glyph, match_glyph, match_glyph}},
{nullptr, nullptr, nullptr}
};
return rule_set.would_apply (c, lookup_context);
}
const Coverage &get_coverage () const { return this+coverage; }
bool apply (hb_ot_apply_context_t *c) const
{
TRACE_APPLY (this);
unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
if (likely (index == NOT_COVERED)) return_trace (false);
const ChainRuleSet &rule_set = this+ruleSet[index];
struct ChainContextApplyLookupContext lookup_context = {
{{match_glyph, match_glyph, match_glyph}},
{nullptr, nullptr, nullptr}
};
return_trace (rule_set.apply (c, lookup_context));
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
const hb_map_t &glyph_map = *c->plan->glyph_map;
auto *out = c->serializer->start_embed (*this);
if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
out->format = format;
const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups;
hb_sorted_vector_t<hb_codepoint_t> new_coverage;
+ hb_zip (this+coverage, ruleSet)
| hb_filter (glyphset, hb_first)
| hb_filter (subset_offset_array (c, out->ruleSet, this, lookup_map), hb_second)
| hb_map (hb_first)
| hb_map (glyph_map)
| hb_sink (new_coverage)
;
out->coverage.serialize_serialize (c->serializer, new_coverage.iter ());
return_trace (bool (new_coverage));
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (coverage.sanitize (c, this) && ruleSet.sanitize (c, this));
}
protected:
HBUINT16 format; /* Format identifier--format = 1 */
typename Types::template OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of table */
Array16Of<typename Types::template OffsetTo<ChainRuleSet>>
ruleSet; /* Array of ChainRuleSet tables
* ordered by Coverage Index */
public:
DEFINE_SIZE_ARRAY (2 + 2 * Types::size, ruleSet);
};
template <typename Types>
struct ChainContextFormat2_5
{
using ChainRuleSet = OT::ChainRuleSet<SmallTypes>;
bool intersects (const hb_set_t *glyphs) const
{
if (!(this+coverage).intersects (glyphs))
return false;
const ClassDef &backtrack_class_def = this+backtrackClassDef;
const ClassDef &input_class_def = this+inputClassDef;
const ClassDef &lookahead_class_def = this+lookaheadClassDef;
struct ChainContextClosureLookupContext lookup_context = {
{intersects_class, intersected_class_glyphs},
ContextFormat::ClassBasedContext,
{&backtrack_class_def,
&input_class_def,
&lookahead_class_def}
};
hb_set_t retained_coverage_glyphs;
(this+coverage).intersect_set (*glyphs, retained_coverage_glyphs);
hb_set_t coverage_glyph_classes;
input_class_def.intersected_classes (&retained_coverage_glyphs, &coverage_glyph_classes);
return
+ hb_iter (ruleSet)
| hb_map (hb_add (this))
| hb_enumerate
| hb_map ([&] (const hb_pair_t<unsigned, const ChainRuleSet &> p)
{ return input_class_def.intersects_class (glyphs, p.first) &&
coverage_glyph_classes.has (p.first) &&
p.second.intersects (glyphs, lookup_context); })
| hb_any
;
}
bool may_have_non_1to1 () const
{ return true; }
void closure (hb_closure_context_t *c) const
{
if (!(this+coverage).intersects (c->glyphs))
return;
hb_set_t& cur_active_glyphs = c->push_cur_active_glyphs ();
get_coverage ().intersect_set (c->previous_parent_active_glyphs (),
cur_active_glyphs);
const ClassDef &backtrack_class_def = this+backtrackClassDef;
const ClassDef &input_class_def = this+inputClassDef;
const ClassDef &lookahead_class_def = this+lookaheadClassDef;
struct ChainContextClosureLookupContext lookup_context = {
{intersects_class, intersected_class_glyphs},
ContextFormat::ClassBasedContext,
{&backtrack_class_def,
&input_class_def,
&lookahead_class_def}
};
+ hb_enumerate (ruleSet)
| hb_filter ([&] (unsigned _)
{ return input_class_def.intersects_class (&c->parent_active_glyphs (), _); },
hb_first)
| hb_apply ([&] (const hb_pair_t<unsigned, const typename Types::template OffsetTo<ChainRuleSet>&> _)
{
const ChainRuleSet& chainrule_set = this+_.second;
chainrule_set.closure (c, _.first, lookup_context);
})
;
c->pop_cur_done_glyphs ();
}
void closure_lookups (hb_closure_lookups_context_t *c) const
{
if (!(this+coverage).intersects (c->glyphs))
return;
const ClassDef &backtrack_class_def = this+backtrackClassDef;
const ClassDef &input_class_def = this+inputClassDef;
const ClassDef &lookahead_class_def = this+lookaheadClassDef;
struct ChainContextClosureLookupContext lookup_context = {
{intersects_class, intersected_class_glyphs},
ContextFormat::ClassBasedContext,
{&backtrack_class_def,
&input_class_def,
&lookahead_class_def}
};
+ hb_iter (ruleSet)
| hb_map (hb_add (this))
| hb_enumerate
| hb_filter([&] (unsigned klass)
{ return input_class_def.intersects_class (c->glyphs, klass); }, hb_first)
| hb_map (hb_second)
| hb_apply ([&] (const ChainRuleSet &_)
{ _.closure_lookups (c, lookup_context); })
;
}
void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {}
void collect_glyphs (hb_collect_glyphs_context_t *c) const
{
(this+coverage).collect_coverage (c->input);
const ClassDef &backtrack_class_def = this+backtrackClassDef;
const ClassDef &input_class_def = this+inputClassDef;
const ClassDef &lookahead_class_def = this+lookaheadClassDef;
struct ChainContextCollectGlyphsLookupContext lookup_context = {
{collect_class},
{&backtrack_class_def,
&input_class_def,
&lookahead_class_def}
};
+ hb_iter (ruleSet)
| hb_map (hb_add (this))
| hb_apply ([&] (const ChainRuleSet &_) { _.collect_glyphs (c, lookup_context); })
;
}
bool would_apply (hb_would_apply_context_t *c) const
{
const ClassDef &backtrack_class_def = this+backtrackClassDef;
const ClassDef &input_class_def = this+inputClassDef;
const ClassDef &lookahead_class_def = this+lookaheadClassDef;
unsigned int index = input_class_def.get_class (c->glyphs[0]);
const ChainRuleSet &rule_set = this+ruleSet[index];
struct ChainContextApplyLookupContext lookup_context = {
{{match_class, match_class, match_class}},
{&backtrack_class_def,
&input_class_def,
&lookahead_class_def}
};
return rule_set.would_apply (c, lookup_context);
}
const Coverage &get_coverage () const { return this+coverage; }
unsigned cache_cost () const
{
unsigned c = (this+lookaheadClassDef).cost () * ruleSet.len;
return c >= 4 ? c : 0;
}
bool cache_func (hb_ot_apply_context_t *c, bool enter) const
{
if (enter)
{
if (!HB_BUFFER_TRY_ALLOCATE_VAR (c->buffer, syllable))
return false;
auto &info = c->buffer->info;
unsigned count = c->buffer->len;
for (unsigned i = 0; i < count; i++)
info[i].syllable() = 255;
c->new_syllables = 255;
return true;
}
else
{
c->new_syllables = (unsigned) -1;
HB_BUFFER_DEALLOCATE_VAR (c->buffer, syllable);
return true;
}
}
bool apply (hb_ot_apply_context_t *c, bool cached = false) const
{
TRACE_APPLY (this);
unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);
if (likely (index == NOT_COVERED)) return_trace (false);
const ClassDef &backtrack_class_def = this+backtrackClassDef;
const ClassDef &input_class_def = this+inputClassDef;
const ClassDef &lookahead_class_def = this+lookaheadClassDef;
/* For ChainContextFormat2_5 we cache the LookaheadClassDef instead of InputClassDef.
* The reason is that most heavy fonts want to identify a glyph in context and apply
* a lookup to it. In this scenario, the length of the input sequence is one, whereas
* the lookahead / backtrack are typically longer. The one glyph in input sequence is
* looked-up below and no input glyph is looked up in individual rules, whereas the
* lookahead and backtrack glyphs are tried. Since we match lookahead before backtrack,
* we should cache lookahead. This decisions showed a 20% improvement in shaping of
* the Gulzar font.
*/
struct ChainContextApplyLookupContext lookup_context = {
{{cached && &backtrack_class_def == &input_class_def ? match_class_cached : match_class,
cached && &input_class_def == &lookahead_class_def ? match_class_cached : match_class,
cached ? match_class_cached : match_class}},
{&backtrack_class_def,
&input_class_def,
&lookahead_class_def}
};
index = input_class_def.get_class (c->buffer->cur().codepoint);
const ChainRuleSet &rule_set = this+ruleSet[index];
return_trace (rule_set.apply (c, lookup_context));
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
auto *out = c->serializer->start_embed (*this);
if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
out->format = format;
out->coverage.serialize_subset (c, coverage, this);
hb_map_t backtrack_klass_map;
hb_map_t input_klass_map;
hb_map_t lookahead_klass_map;
out->backtrackClassDef.serialize_subset (c, backtrackClassDef, this, &backtrack_klass_map);
// TODO: subset inputClassDef based on glyphs survived in Coverage subsetting
out->inputClassDef.serialize_subset (c, inputClassDef, this, &input_klass_map);
out->lookaheadClassDef.serialize_subset (c, lookaheadClassDef, this, &lookahead_klass_map);
if (unlikely (!c->serializer->propagate_error (backtrack_klass_map,
input_klass_map,
lookahead_klass_map)))
return_trace (false);
const hb_set_t* glyphset = c->plan->glyphset_gsub ();
hb_set_t retained_coverage_glyphs;
(this+coverage).intersect_set (*glyphset, retained_coverage_glyphs);
hb_set_t coverage_glyph_classes;
(this+inputClassDef).intersected_classes (&retained_coverage_glyphs, &coverage_glyph_classes);
int non_zero_index = -1, index = 0;
bool ret = true;
const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups;
auto last_non_zero = c->serializer->snapshot ();
for (const auto& _ : + hb_enumerate (ruleSet)
| hb_filter (input_klass_map, hb_first))
{
auto *o = out->ruleSet.serialize_append (c->serializer);
if (unlikely (!o))
{
ret = false;
break;
}
if (coverage_glyph_classes.has (_.first) &&
o->serialize_subset (c, _.second, this,
lookup_map,
&backtrack_klass_map,
&input_klass_map,
&lookahead_klass_map))
{
last_non_zero = c->serializer->snapshot ();
non_zero_index = index;
}
index++;
}
if (!ret || non_zero_index == -1) return_trace (false);
// prune empty trailing ruleSets
if (index > non_zero_index) {
c->serializer->revert (last_non_zero);
out->ruleSet.len = non_zero_index + 1;
}
return_trace (bool (out->ruleSet));
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (coverage.sanitize (c, this) &&
backtrackClassDef.sanitize (c, this) &&
inputClassDef.sanitize (c, this) &&
lookaheadClassDef.sanitize (c, this) &&
ruleSet.sanitize (c, this));
}
protected:
HBUINT16 format; /* Format identifier--format = 2 */
typename Types::template OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of table */
typename Types::template OffsetTo<ClassDef>
backtrackClassDef; /* Offset to glyph ClassDef table
* containing backtrack sequence
* data--from beginning of table */
typename Types::template OffsetTo<ClassDef>
inputClassDef; /* Offset to glyph ClassDef
* table containing input sequence
* data--from beginning of table */
typename Types::template OffsetTo<ClassDef>
lookaheadClassDef; /* Offset to glyph ClassDef table
* containing lookahead sequence
* data--from beginning of table */
Array16Of<typename Types::template OffsetTo<ChainRuleSet>>
ruleSet; /* Array of ChainRuleSet tables
* ordered by class */
public:
DEFINE_SIZE_ARRAY (4 + 4 * Types::size, ruleSet);
};
struct ChainContextFormat3
{
using RuleSet = OT::RuleSet<SmallTypes>;
bool intersects (const hb_set_t *glyphs) const
{
const auto &input = StructAfter<decltype (inputX)> (backtrack);
if (!(this+input[0]).intersects (glyphs))
return false;
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
struct ChainContextClosureLookupContext lookup_context = {
{intersects_coverage, intersected_coverage_glyphs},
ContextFormat::CoverageBasedContext,
{this, this, this}
};
return chain_context_intersects (glyphs,
backtrack.len, (const HBUINT16 *) backtrack.arrayZ,
input.len, (const HBUINT16 *) input.arrayZ + 1,
lookahead.len, (const HBUINT16 *) lookahead.arrayZ,
lookup_context);
}
bool may_have_non_1to1 () const
{ return true; }
void closure (hb_closure_context_t *c) const
{
const auto &input = StructAfter<decltype (inputX)> (backtrack);
if (!(this+input[0]).intersects (c->glyphs))
return;
hb_set_t& cur_active_glyphs = c->push_cur_active_glyphs ();
get_coverage ().intersect_set (c->previous_parent_active_glyphs (),
cur_active_glyphs);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
struct ChainContextClosureLookupContext lookup_context = {
{intersects_coverage, intersected_coverage_glyphs},
ContextFormat::CoverageBasedContext,
{this, this, this}
};
chain_context_closure_lookup (c,
backtrack.len, (const HBUINT16 *) backtrack.arrayZ,
input.len, (const HBUINT16 *) input.arrayZ + 1,
lookahead.len, (const HBUINT16 *) lookahead.arrayZ,
lookup.len, lookup.arrayZ,
0, lookup_context);
c->pop_cur_done_glyphs ();
}
void closure_lookups (hb_closure_lookups_context_t *c) const
{
if (!intersects (c->glyphs))
return;
const auto &input = StructAfter<decltype (inputX)> (backtrack);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
recurse_lookups (c, lookup.len, lookup.arrayZ);
}
void collect_variation_indices (hb_collect_variation_indices_context_t *c) const {}
void collect_glyphs (hb_collect_glyphs_context_t *c) const
{
const auto &input = StructAfter<decltype (inputX)> (backtrack);
(this+input[0]).collect_coverage (c->input);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
struct ChainContextCollectGlyphsLookupContext lookup_context = {
{collect_coverage},
{this, this, this}
};
chain_context_collect_glyphs_lookup (c,
backtrack.len, (const HBUINT16 *) backtrack.arrayZ,
input.len, (const HBUINT16 *) input.arrayZ + 1,
lookahead.len, (const HBUINT16 *) lookahead.arrayZ,
lookup.len, lookup.arrayZ,
lookup_context);
}
bool would_apply (hb_would_apply_context_t *c) const
{
const auto &input = StructAfter<decltype (inputX)> (backtrack);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
struct ChainContextApplyLookupContext lookup_context = {
{{match_coverage, match_coverage, match_coverage}},
{this, this, this}
};
return chain_context_would_apply_lookup (c,
backtrack.len, (const HBUINT16 *) backtrack.arrayZ,
input.len, (const HBUINT16 *) input.arrayZ + 1,
lookahead.len, (const HBUINT16 *) lookahead.arrayZ,
lookup.len, lookup.arrayZ, lookup_context);
}
const Coverage &get_coverage () const
{
const auto &input = StructAfter<decltype (inputX)> (backtrack);
return this+input[0];
}
bool apply (hb_ot_apply_context_t *c) const
{
TRACE_APPLY (this);
const auto &input = StructAfter<decltype (inputX)> (backtrack);
unsigned int index = (this+input[0]).get_coverage (c->buffer->cur().codepoint);
if (likely (index == NOT_COVERED)) return_trace (false);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
struct ChainContextApplyLookupContext lookup_context = {
{{match_coverage, match_coverage, match_coverage}},
{this, this, this}
};
return_trace (chain_context_apply_lookup (c,
backtrack.len, (const HBUINT16 *) backtrack.arrayZ,
input.len, (const HBUINT16 *) input.arrayZ + 1,
lookahead.len, (const HBUINT16 *) lookahead.arrayZ,
lookup.len, lookup.arrayZ, lookup_context));
}
template<typename Iterator,
hb_requires (hb_is_iterator (Iterator))>
bool serialize_coverage_offsets (hb_subset_context_t *c, Iterator it, const void* base) const
{
TRACE_SERIALIZE (this);
auto *out = c->serializer->start_embed<Array16OfOffset16To<Coverage>> ();
if (unlikely (!c->serializer->allocate_size<HBUINT16> (HBUINT16::static_size)))
return_trace (false);
for (auto& offset : it) {
auto *o = out->serialize_append (c->serializer);
if (unlikely (!o) || !o->serialize_subset (c, offset, base))
return_trace (false);
}
return_trace (true);
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
auto *out = c->serializer->start_embed (this);
if (unlikely (!out)) return_trace (false);
if (unlikely (!c->serializer->embed (this->format))) return_trace (false);
if (!serialize_coverage_offsets (c, backtrack.iter (), this))
return_trace (false);
const auto &input = StructAfter<decltype (inputX)> (backtrack);
if (!serialize_coverage_offsets (c, input.iter (), this))
return_trace (false);
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
if (!serialize_coverage_offsets (c, lookahead.iter (), this))
return_trace (false);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
const hb_map_t *lookup_map = c->table_tag == HB_OT_TAG_GSUB ? c->plan->gsub_lookups : c->plan->gpos_lookups;
HBUINT16 *lookupCount = c->serializer->copy<HBUINT16> (lookup.len);
if (!lookupCount) return_trace (false);
unsigned count = serialize_lookuprecord_array (c->serializer, lookup.as_array (), lookup_map);
return_trace (c->serializer->check_assign (*lookupCount, count, HB_SERIALIZE_ERROR_INT_OVERFLOW));
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (!backtrack.sanitize (c, this)) return_trace (false);
const auto &input = StructAfter<decltype (inputX)> (backtrack);
if (!input.sanitize (c, this)) return_trace (false);
if (!input.len) return_trace (false); /* To be consistent with Context. */
const auto &lookahead = StructAfter<decltype (lookaheadX)> (input);
if (!lookahead.sanitize (c, this)) return_trace (false);
const auto &lookup = StructAfter<decltype (lookupX)> (lookahead);
return_trace (lookup.sanitize (c));
}
protected:
HBUINT16 format; /* Format identifier--format = 3 */
Array16OfOffset16To<Coverage>
backtrack; /* Array of coverage tables
* in backtracking sequence, in glyph
* sequence order */
Array16OfOffset16To<Coverage>
inputX ; /* Array of coverage
* tables in input sequence, in glyph
* sequence order */
Array16OfOffset16To<Coverage>
lookaheadX; /* Array of coverage tables
* in lookahead sequence, in glyph
* sequence order */
Array16Of<LookupRecord>
lookupX; /* Array of LookupRecords--in
* design order) */
public:
DEFINE_SIZE_MIN (10);
};
struct ChainContext
{
template <typename context_t, typename ...Ts>
typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
{
TRACE_DISPATCH (this, u.format);
if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ());
switch (u.format) {
case 1: return_trace (c->dispatch (u.format1, std::forward<Ts> (ds)...));
case 2: return_trace (c->dispatch (u.format2, std::forward<Ts> (ds)...));
case 3: return_trace (c->dispatch (u.format3, std::forward<Ts> (ds)...));
#ifndef HB_NO_BEYOND_64K
case 4: return_trace (c->dispatch (u.format4, std::forward<Ts> (ds)...));
case 5: return_trace (c->dispatch (u.format5, std::forward<Ts> (ds)...));
#endif
default:return_trace (c->default_return_value ());
}
}
protected:
union {
HBUINT16 format; /* Format identifier */
ChainContextFormat1_4<SmallTypes> format1;
ChainContextFormat2_5<SmallTypes> format2;
ChainContextFormat3 format3;
#ifndef HB_NO_BEYOND_64K
ChainContextFormat1_4<MediumTypes> format4;
ChainContextFormat2_5<MediumTypes> format5;
#endif
} u;
};
template <typename T>
struct ExtensionFormat1
{
unsigned int get_type () const { return extensionLookupType; }
template <typename X>
const X& get_subtable () const
{ return this + reinterpret_cast<const Offset32To<typename T::SubTable> &> (extensionOffset); }
template <typename context_t, typename ...Ts>
typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
{
TRACE_DISPATCH (this, format);
if (unlikely (!c->may_dispatch (this, this))) return_trace (c->no_dispatch_return_value ());
return_trace (get_subtable<typename T::SubTable> ().dispatch (c, get_type (), std::forward<Ts> (ds)...));
}
void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
{ dispatch (c); }
/* This is called from may_dispatch() above with hb_sanitize_context_t. */
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) &&
extensionLookupType != T::SubTable::Extension);
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
auto *out = c->serializer->start_embed (this);
if (unlikely (!out || !c->serializer->extend_min (out))) return_trace (false);
out->format = format;
out->extensionLookupType = extensionLookupType;
const auto& src_offset =
reinterpret_cast<const Offset32To<typename T::SubTable> &> (extensionOffset);
auto& dest_offset =
reinterpret_cast<Offset32To<typename T::SubTable> &> (out->extensionOffset);
return_trace (dest_offset.serialize_subset (c, src_offset, this, get_type ()));
}
protected:
HBUINT16 format; /* Format identifier. Set to 1. */
HBUINT16 extensionLookupType; /* Lookup type of subtable referenced
* by ExtensionOffset (i.e. the
* extension subtable). */
Offset32 extensionOffset; /* Offset to the extension subtable,
* of lookup type subtable. */
public:
DEFINE_SIZE_STATIC (8);
};
template <typename T>
struct Extension
{
unsigned int get_type () const
{
switch (u.format) {
case 1: return u.format1.get_type ();
default:return 0;
}
}
template <typename X>
const X& get_subtable () const
{
switch (u.format) {
case 1: return u.format1.template get_subtable<typename T::SubTable> ();
default:return Null (typename T::SubTable);
}
}
// Specialization of dispatch for subset. dispatch() normally just
// dispatches to the sub table this points too, but for subset
// we need to run subset on this subtable too.
template <typename ...Ts>
typename hb_subset_context_t::return_t dispatch (hb_subset_context_t *c, Ts&&... ds) const
{
switch (u.format) {
case 1: return u.format1.subset (c);
default: return c->default_return_value ();
}
}
template <typename context_t, typename ...Ts>
typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
{
TRACE_DISPATCH (this, u.format);
if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ());
switch (u.format) {
case 1: return_trace (u.format1.dispatch (c, std::forward<Ts> (ds)...));
default:return_trace (c->default_return_value ());
}
}
protected:
union {
HBUINT16 format; /* Format identifier */
ExtensionFormat1<T> format1;
} u;
};
/*
* GSUB/GPOS Common
*/
struct hb_ot_layout_lookup_accelerator_t
{
template <typename TLookup>
void init (const TLookup &lookup)
{
digest.init ();
lookup.collect_coverage (&digest);
subtables.init ();
OT::hb_accelerate_subtables_context_t c_accelerate_subtables (subtables);
lookup.dispatch (&c_accelerate_subtables);
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
cache_user_idx = c_accelerate_subtables.cache_user_idx;
for (unsigned i = 0; i < subtables.length; i++)
if (i != cache_user_idx)
subtables[i].apply_cached_func = subtables[i].apply_func;
#endif
}
void fini () { subtables.fini (); }
bool may_have (hb_codepoint_t g) const
{ return digest.may_have (g); }
bool apply (hb_ot_apply_context_t *c, bool use_cache) const
{
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
if (use_cache)
{
for (unsigned int i = 0; i < subtables.length; i++)
if (subtables[i].apply_cached (c))
return true;
}
else
#endif
{
for (unsigned int i = 0; i < subtables.length; i++)
if (subtables[i].apply (c))
return true;
}
return false;
}
bool cache_enter (OT::hb_ot_apply_context_t *c) const
{
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
return cache_user_idx != (unsigned) -1 &&
subtables[cache_user_idx].cache_enter (c);
#else
return false;
#endif
}
void cache_leave (OT::hb_ot_apply_context_t *c) const
{
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
subtables[cache_user_idx].cache_leave (c);
#endif
}
private:
hb_set_digest_t digest;
hb_accelerate_subtables_context_t::array_t subtables;
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
unsigned cache_user_idx = (unsigned) -1;
#endif
};
template <typename Types>
struct GSUBGPOSVersion1_2
{
friend struct GSUBGPOS;
protected:
FixedVersion<>version; /* Version of the GSUB/GPOS table--initially set
* to 0x00010000u */
typename Types:: template OffsetTo<ScriptList>
scriptList; /* ScriptList table */
typename Types::template OffsetTo<FeatureList>
featureList; /* FeatureList table */
typename Types::template OffsetTo<LookupList<Types>>
lookupList; /* LookupList table */
Offset32To<FeatureVariations>
featureVars; /* Offset to Feature Variations
table--from beginning of table
* (may be NULL). Introduced
* in version 0x00010001. */
public:
DEFINE_SIZE_MIN (4 + 3 * Types::size);
unsigned int get_size () const
{
return min_size +
(version.to_int () >= 0x00010001u ? featureVars.static_size : 0);
}
const typename Types::template OffsetTo<LookupList<Types>>* get_lookup_list_offset () const
{
return &lookupList;
}
template <typename TLookup>
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
typedef List16OfOffsetTo<TLookup, typename Types::HBUINT> TLookupList;
if (unlikely (!(scriptList.sanitize (c, this) &&
featureList.sanitize (c, this) &&
reinterpret_cast<const typename Types::template OffsetTo<TLookupList> &> (lookupList).sanitize (c, this))))
return_trace (false);
#ifndef HB_NO_VAR
if (unlikely (!(version.to_int () < 0x00010001u || featureVars.sanitize (c, this))))
return_trace (false);
#endif
return_trace (true);
}
template <typename TLookup>
bool subset (hb_subset_layout_context_t *c) const
{
TRACE_SUBSET (this);
auto *out = c->subset_context->serializer->embed (*this);
if (unlikely (!out)) return_trace (false);
typedef LookupOffsetList<TLookup, typename Types::HBUINT> TLookupList;
reinterpret_cast<typename Types::template OffsetTo<TLookupList> &> (out->lookupList)
.serialize_subset (c->subset_context,
reinterpret_cast<const typename Types::template OffsetTo<TLookupList> &> (lookupList),
this,
c);
reinterpret_cast<typename Types::template OffsetTo<RecordListOfFeature> &> (out->featureList)
.serialize_subset (c->subset_context,
reinterpret_cast<const typename Types::template OffsetTo<RecordListOfFeature> &> (featureList),
this,
c);
out->scriptList.serialize_subset (c->subset_context,
scriptList,
this,
c);
#ifndef HB_NO_VAR
if (version.to_int () >= 0x00010001u)
{
bool ret = out->featureVars.serialize_subset (c->subset_context, featureVars, this, c);
if (!ret && version.major == 1)
{
out->version.major = 1;
out->version.minor = 0;
}
}
#endif
return_trace (true);
}
};
struct GSUBGPOS
{
unsigned int get_size () const
{
switch (u.version.major) {
case 1: return u.version1.get_size ();
#ifndef HB_NO_BEYOND_64K
case 2: return u.version2.get_size ();
#endif
default: return u.version.static_size;
}
}
template <typename TLookup>
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!u.version.sanitize (c))) return_trace (false);
switch (u.version.major) {
case 1: return_trace (u.version1.sanitize<TLookup> (c));
#ifndef HB_NO_BEYOND_64K
case 2: return_trace (u.version2.sanitize<TLookup> (c));
#endif
default: return_trace (true);
}
}
template <typename TLookup>
bool subset (hb_subset_layout_context_t *c) const
{
switch (u.version.major) {
case 1: return u.version1.subset<TLookup> (c);
#ifndef HB_NO_BEYOND_64K
case 2: return u.version2.subset<TLookup> (c);
#endif
default: return false;
}
}
const ScriptList &get_script_list () const
{
switch (u.version.major) {
case 1: return this+u.version1.scriptList;
#ifndef HB_NO_BEYOND_64K
case 2: return this+u.version2.scriptList;
#endif
default: return Null (ScriptList);
}
}
const FeatureList &get_feature_list () const
{
switch (u.version.major) {
case 1: return this+u.version1.featureList;
#ifndef HB_NO_BEYOND_64K
case 2: return this+u.version2.featureList;
#endif
default: return Null (FeatureList);
}
}
unsigned int get_lookup_count () const
{
switch (u.version.major) {
case 1: return (this+u.version1.lookupList).len;
#ifndef HB_NO_BEYOND_64K
case 2: return (this+u.version2.lookupList).len;
#endif
default: return 0;
}
}
const Lookup& get_lookup (unsigned int i) const
{
switch (u.version.major) {
case 1: return (this+u.version1.lookupList)[i];
#ifndef HB_NO_BEYOND_64K
case 2: return (this+u.version2.lookupList)[i];
#endif
default: return Null (Lookup);
}
}
const FeatureVariations &get_feature_variations () const
{
switch (u.version.major) {
case 1: return (u.version.to_int () >= 0x00010001u ? this+u.version1.featureVars : Null (FeatureVariations));
#ifndef HB_NO_BEYOND_64K
case 2: return this+u.version2.featureVars;
#endif
default: return Null (FeatureVariations);
}
}
bool has_data () const { return u.version.to_int (); }
unsigned int get_script_count () const
{ return get_script_list ().len; }
const Tag& get_script_tag (unsigned int i) const
{ return get_script_list ().get_tag (i); }
unsigned int get_script_tags (unsigned int start_offset,
unsigned int *script_count /* IN/OUT */,
hb_tag_t *script_tags /* OUT */) const
{ return get_script_list ().get_tags (start_offset, script_count, script_tags); }
const Script& get_script (unsigned int i) const
{ return get_script_list ()[i]; }
bool find_script_index (hb_tag_t tag, unsigned int *index) const
{ return get_script_list ().find_index (tag, index); }
unsigned int get_feature_count () const
{ return get_feature_list ().len; }
hb_tag_t get_feature_tag (unsigned int i) const
{ return i == Index::NOT_FOUND_INDEX ? HB_TAG_NONE : get_feature_list ().get_tag (i); }
unsigned int get_feature_tags (unsigned int start_offset,
unsigned int *feature_count /* IN/OUT */,
hb_tag_t *feature_tags /* OUT */) const
{ return get_feature_list ().get_tags (start_offset, feature_count, feature_tags); }
const Feature& get_feature (unsigned int i) const
{ return get_feature_list ()[i]; }
bool find_feature_index (hb_tag_t tag, unsigned int *index) const
{ return get_feature_list ().find_index (tag, index); }
bool find_variations_index (const int *coords, unsigned int num_coords,
unsigned int *index) const
{
#ifdef HB_NO_VAR
*index = FeatureVariations::NOT_FOUND_INDEX;
return false;
#endif
return get_feature_variations ().find_index (coords, num_coords, index);
}
const Feature& get_feature_variation (unsigned int feature_index,
unsigned int variations_index) const
{
#ifndef HB_NO_VAR
if (FeatureVariations::NOT_FOUND_INDEX != variations_index &&
u.version.to_int () >= 0x00010001u)
{
const Feature *feature = get_feature_variations ().find_substitute (variations_index,
feature_index);
if (feature)
return *feature;
}
#endif
return get_feature (feature_index);
}
void feature_variation_collect_lookups (const hb_set_t *feature_indexes,
hb_set_t *lookup_indexes /* OUT */) const
{
#ifndef HB_NO_VAR
get_feature_variations ().collect_lookups (feature_indexes, lookup_indexes);
#endif
}
template <typename TLookup>
void closure_lookups (hb_face_t *face,
const hb_set_t *glyphs,
hb_set_t *lookup_indexes /* IN/OUT */) const
{
hb_set_t visited_lookups, inactive_lookups;
OT::hb_closure_lookups_context_t c (face, glyphs, &visited_lookups, &inactive_lookups);
c.set_recurse_func (TLookup::template dispatch_recurse_func<hb_closure_lookups_context_t>);
for (unsigned lookup_index : + hb_iter (lookup_indexes))
reinterpret_cast<const TLookup &> (get_lookup (lookup_index)).closure_lookups (&c, lookup_index);
hb_set_union (lookup_indexes, &visited_lookups);
hb_set_subtract (lookup_indexes, &inactive_lookups);
}
void prune_langsys (const hb_map_t *duplicate_feature_map,
hb_hashmap_t<unsigned, hb::unique_ptr<hb_set_t>> *script_langsys_map,
hb_set_t *new_feature_indexes /* OUT */) const
{
hb_prune_langsys_context_t c (this, script_langsys_map, duplicate_feature_map, new_feature_indexes);
unsigned count = get_script_count ();
for (unsigned script_index = 0; script_index < count; script_index++)
{
const Script& s = get_script (script_index);
s.prune_langsys (&c, script_index);
}
}
void prune_features (const hb_map_t *lookup_indices, /* IN */
hb_set_t *feature_indices /* IN/OUT */) const
{
#ifndef HB_NO_VAR
// This is the set of feature indices which have alternate versions defined
// if the FeatureVariation's table and the alternate version(s) intersect the
// set of lookup indices.
hb_set_t alternate_feature_indices;
get_feature_variations ().closure_features (lookup_indices, &alternate_feature_indices);
if (unlikely (alternate_feature_indices.in_error()))
{
feature_indices->err ();
return;
}
#endif
for (unsigned i : feature_indices->iter())
{
const Feature& f = get_feature (i);
hb_tag_t tag = get_feature_tag (i);
if (tag == HB_TAG ('p', 'r', 'e', 'f'))
// Note: Never ever drop feature 'pref', even if it's empty.
// HarfBuzz chooses shaper for Khmer based on presence of this
// feature. See thread at:
// http://lists.freedesktop.org/archives/harfbuzz/2012-November/002660.html
continue;
if (!f.featureParams.is_null () &&
tag == HB_TAG ('s', 'i', 'z', 'e'))
continue;
if (!f.intersects_lookup_indexes (lookup_indices)
#ifndef HB_NO_VAR
&& !alternate_feature_indices.has (i)
#endif
)
feature_indices->del (i);
}
}
template <typename T>
struct accelerator_t
{
accelerator_t (hb_face_t *face)
{
this->table = hb_sanitize_context_t ().reference_table<T> (face);
if (unlikely (this->table->is_blocklisted (this->table.get_blob (), face)))
{
hb_blob_destroy (this->table.get_blob ());
this->table = hb_blob_get_empty ();
}
this->lookup_count = table->get_lookup_count ();
this->accels = (hb_ot_layout_lookup_accelerator_t *) hb_calloc (this->lookup_count, sizeof (hb_ot_layout_lookup_accelerator_t));
if (unlikely (!this->accels))
{
this->lookup_count = 0;
this->table.destroy ();
this->table = hb_blob_get_empty ();
}
for (unsigned int i = 0; i < this->lookup_count; i++)
this->accels[i].init (table->get_lookup (i));
}
~accelerator_t ()
{
for (unsigned int i = 0; i < this->lookup_count; i++)
this->accels[i].fini ();
hb_free (this->accels);
this->table.destroy ();
}
hb_blob_ptr_t<T> table;
unsigned int lookup_count;
hb_ot_layout_lookup_accelerator_t *accels;
};
protected:
union {
FixedVersion<> version; /* Version identifier */
GSUBGPOSVersion1_2<SmallTypes> version1;
#ifndef HB_NO_BEYOND_64K
GSUBGPOSVersion1_2<MediumTypes> version2;
#endif
} u;
public:
DEFINE_SIZE_MIN (4);
};
} /* namespace OT */
#endif /* HB_OT_LAYOUT_GSUBGPOS_HH */