/*
* Copyright © 1998-2004 David Turner and Werner Lemberg
* Copyright © 2006 Behdad Esfahbod
* Copyright © 2007,2008,2009 Red Hat, Inc.
* Copyright © 2012,2013 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Red Hat Author(s): Behdad Esfahbod
* Google Author(s): Behdad Esfahbod
*/
#include "hb-ot-layout-private.hh"
#include "hb-ot-layout-gdef-table.hh"
#include "hb-ot-layout-gsub-table.hh"
#include "hb-ot-layout-gpos-table.hh"
#include "hb-ot-layout-jstf-table.hh"
#include "hb-ot-map-private.hh"
#include <stdlib.h>
#include <string.h>
HB_SHAPER_DATA_ENSURE_DECLARE(ot, face)
hb_ot_layout_t *
_hb_ot_layout_create (hb_face_t *face)
{
hb_ot_layout_t *layout = (hb_ot_layout_t *) calloc (1, sizeof (hb_ot_layout_t));
if (unlikely (!layout))
return NULL;
layout->gdef_blob = OT::Sanitizer<OT::GDEF>::sanitize (face->reference_table (HB_OT_TAG_GDEF));
layout->gdef = OT::Sanitizer<OT::GDEF>::lock_instance (layout->gdef_blob);
layout->gsub_blob = OT::Sanitizer<OT::GSUB>::sanitize (face->reference_table (HB_OT_TAG_GSUB));
layout->gsub = OT::Sanitizer<OT::GSUB>::lock_instance (layout->gsub_blob);
layout->gpos_blob = OT::Sanitizer<OT::GPOS>::sanitize (face->reference_table (HB_OT_TAG_GPOS));
layout->gpos = OT::Sanitizer<OT::GPOS>::lock_instance (layout->gpos_blob);
layout->gsub_lookup_count = layout->gsub->get_lookup_count ();
layout->gpos_lookup_count = layout->gpos->get_lookup_count ();
layout->gsub_accels = (hb_ot_layout_lookup_accelerator_t *) calloc (layout->gsub->get_lookup_count (), sizeof (hb_ot_layout_lookup_accelerator_t));
layout->gpos_accels = (hb_ot_layout_lookup_accelerator_t *) calloc (layout->gpos->get_lookup_count (), sizeof (hb_ot_layout_lookup_accelerator_t));
if (unlikely ((layout->gsub_lookup_count && !layout->gsub_accels) ||
(layout->gpos_lookup_count && !layout->gpos_accels)))
{
_hb_ot_layout_destroy (layout);
return NULL;
}
for (unsigned int i = 0; i < layout->gsub_lookup_count; i++)
layout->gsub_accels[i].init (layout->gsub->get_lookup (i));
for (unsigned int i = 0; i < layout->gpos_lookup_count; i++)
layout->gpos_accels[i].init (layout->gpos->get_lookup (i));
return layout;
}
void
_hb_ot_layout_destroy (hb_ot_layout_t *layout)
{
for (unsigned int i = 0; i < layout->gsub_lookup_count; i++)
layout->gsub_accels[i].fini (layout->gsub->get_lookup (i));
for (unsigned int i = 0; i < layout->gpos_lookup_count; i++)
layout->gpos_accels[i].fini (layout->gpos->get_lookup (i));
free (layout->gsub_accels);
free (layout->gpos_accels);
hb_blob_destroy (layout->gdef_blob);
hb_blob_destroy (layout->gsub_blob);
hb_blob_destroy (layout->gpos_blob);
free (layout);
}
static inline const OT::GDEF&
_get_gdef (hb_face_t *face)
{
if (unlikely (!hb_ot_shaper_face_data_ensure (face))) return OT::Null(OT::GDEF);
return *hb_ot_layout_from_face (face)->gdef;
}
static inline const OT::GSUB&
_get_gsub (hb_face_t *face)
{
if (unlikely (!hb_ot_shaper_face_data_ensure (face))) return OT::Null(OT::GSUB);
return *hb_ot_layout_from_face (face)->gsub;
}
static inline const OT::GPOS&
_get_gpos (hb_face_t *face)
{
if (unlikely (!hb_ot_shaper_face_data_ensure (face))) return OT::Null(OT::GPOS);
return *hb_ot_layout_from_face (face)->gpos;
}
/*
* GDEF
*/
hb_bool_t
hb_ot_layout_has_glyph_classes (hb_face_t *face)
{
return _get_gdef (face).has_glyph_classes ();
}
hb_ot_layout_glyph_class_t
hb_ot_layout_get_glyph_class (hb_face_t *face,
hb_codepoint_t glyph)
{
return (hb_ot_layout_glyph_class_t) _get_gdef (face).get_glyph_class (glyph);
}
void
hb_ot_layout_get_glyphs_in_class (hb_face_t *face,
hb_ot_layout_glyph_class_t klass,
hb_set_t *glyphs /* OUT */)
{
return _get_gdef (face).get_glyphs_in_class (klass, glyphs);
}
unsigned int
hb_ot_layout_get_attach_points (hb_face_t *face,
hb_codepoint_t glyph,
unsigned int start_offset,
unsigned int *point_count /* IN/OUT */,
unsigned int *point_array /* OUT */)
{
return _get_gdef (face).get_attach_points (glyph, start_offset, point_count, point_array);
}
unsigned int
hb_ot_layout_get_ligature_carets (hb_font_t *font,
hb_direction_t direction,
hb_codepoint_t glyph,
unsigned int start_offset,
unsigned int *caret_count /* IN/OUT */,
int *caret_array /* OUT */)
{
return _get_gdef (font->face).get_lig_carets (font, direction, glyph, start_offset, caret_count, caret_array);
}
/*
* GSUB/GPOS
*/
static const OT::GSUBGPOS&
get_gsubgpos_table (hb_face_t *face,
hb_tag_t table_tag)
{
switch (table_tag) {
case HB_OT_TAG_GSUB: return _get_gsub (face);
case HB_OT_TAG_GPOS: return _get_gpos (face);
default: return OT::Null(OT::GSUBGPOS);
}
}
unsigned int
hb_ot_layout_table_get_script_tags (hb_face_t *face,
hb_tag_t table_tag,
unsigned int start_offset,
unsigned int *script_count /* IN/OUT */,
hb_tag_t *script_tags /* OUT */)
{
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
return g.get_script_tags (start_offset, script_count, script_tags);
}
#define HB_OT_TAG_LATIN_SCRIPT HB_TAG ('l', 'a', 't', 'n')
hb_bool_t
hb_ot_layout_table_find_script (hb_face_t *face,
hb_tag_t table_tag,
hb_tag_t script_tag,
unsigned int *script_index)
{
ASSERT_STATIC (OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX);
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
if (g.find_script_index (script_tag, script_index))
return true;
/* try finding 'DFLT' */
if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index))
return false;
/* try with 'dflt'; MS site has had typos and many fonts use it now :(.
* including many versions of DejaVu Sans Mono! */
if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index))
return false;
/* try with 'latn'; some old fonts put their features there even though
they're really trying to support Thai, for example :( */
if (g.find_script_index (HB_OT_TAG_LATIN_SCRIPT, script_index))
return false;
if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX;
return false;
}
hb_bool_t
hb_ot_layout_table_choose_script (hb_face_t *face,
hb_tag_t table_tag,
const hb_tag_t *script_tags,
unsigned int *script_index,
hb_tag_t *chosen_script)
{
ASSERT_STATIC (OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX);
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
while (*script_tags)
{
if (g.find_script_index (*script_tags, script_index)) {
if (chosen_script)
*chosen_script = *script_tags;
return true;
}
script_tags++;
}
/* try finding 'DFLT' */
if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) {
if (chosen_script)
*chosen_script = HB_OT_TAG_DEFAULT_SCRIPT;
return false;
}
/* try with 'dflt'; MS site has had typos and many fonts use it now :( */
if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) {
if (chosen_script)
*chosen_script = HB_OT_TAG_DEFAULT_LANGUAGE;
return false;
}
/* try with 'latn'; some old fonts put their features there even though
they're really trying to support Thai, for example :( */
if (g.find_script_index (HB_OT_TAG_LATIN_SCRIPT, script_index)) {
if (chosen_script)
*chosen_script = HB_OT_TAG_LATIN_SCRIPT;
return false;
}
if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX;
if (chosen_script)
*chosen_script = HB_OT_LAYOUT_NO_SCRIPT_INDEX;
return false;
}
unsigned int
hb_ot_layout_table_get_feature_tags (hb_face_t *face,
hb_tag_t table_tag,
unsigned int start_offset,
unsigned int *feature_count /* IN/OUT */,
hb_tag_t *feature_tags /* OUT */)
{
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
return g.get_feature_tags (start_offset, feature_count, feature_tags);
}
unsigned int
hb_ot_layout_script_get_language_tags (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int start_offset,
unsigned int *language_count /* IN/OUT */,
hb_tag_t *language_tags /* OUT */)
{
const OT::Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index);
return s.get_lang_sys_tags (start_offset, language_count, language_tags);
}
hb_bool_t
hb_ot_layout_script_find_language (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
hb_tag_t language_tag,
unsigned int *language_index)
{
ASSERT_STATIC (OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX);
const OT::Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index);
if (s.find_lang_sys_index (language_tag, language_index))
return true;
/* try with 'dflt'; MS site has had typos and many fonts use it now :( */
if (s.find_lang_sys_index (HB_OT_TAG_DEFAULT_LANGUAGE, language_index))
return false;
if (language_index) *language_index = HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX;
return false;
}
hb_bool_t
hb_ot_layout_language_get_required_feature_index (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
unsigned int *feature_index)
{
const OT::LangSys &l = get_gsubgpos_table (face, table_tag).get_script (script_index).get_lang_sys (language_index);
if (feature_index) *feature_index = l.get_required_feature_index ();
return l.has_required_feature ();
}
unsigned int
hb_ot_layout_language_get_feature_indexes (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
unsigned int start_offset,
unsigned int *feature_count /* IN/OUT */,
unsigned int *feature_indexes /* OUT */)
{
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
return l.get_feature_indexes (start_offset, feature_count, feature_indexes);
}
unsigned int
hb_ot_layout_language_get_feature_tags (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
unsigned int start_offset,
unsigned int *feature_count /* IN/OUT */,
hb_tag_t *feature_tags /* OUT */)
{
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
ASSERT_STATIC (sizeof (unsigned int) == sizeof (hb_tag_t));
unsigned int ret = l.get_feature_indexes (start_offset, feature_count, (unsigned int *) feature_tags);
if (feature_tags) {
unsigned int count = *feature_count;
for (unsigned int i = 0; i < count; i++)
feature_tags[i] = g.get_feature_tag ((unsigned int) feature_tags[i]);
}
return ret;
}
hb_bool_t
hb_ot_layout_language_find_feature (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
hb_tag_t feature_tag,
unsigned int *feature_index)
{
ASSERT_STATIC (OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_FEATURE_INDEX);
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
unsigned int num_features = l.get_feature_count ();
for (unsigned int i = 0; i < num_features; i++) {
unsigned int f_index = l.get_feature_index (i);
if (feature_tag == g.get_feature_tag (f_index)) {
if (feature_index) *feature_index = f_index;
return true;
}
}
if (feature_index) *feature_index = HB_OT_LAYOUT_NO_FEATURE_INDEX;
return false;
}
unsigned int
hb_ot_layout_feature_get_lookups (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
unsigned int start_offset,
unsigned int *lookup_count /* IN/OUT */,
unsigned int *lookup_indexes /* OUT */)
{
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
const OT::Feature &f = g.get_feature (feature_index);
return f.get_lookup_indexes (start_offset, lookup_count, lookup_indexes);
}
unsigned int
hb_ot_layout_table_get_lookup_count (hb_face_t *face,
hb_tag_t table_tag)
{
switch (table_tag)
{
case HB_OT_TAG_GSUB:
{
return hb_ot_layout_from_face (face)->gsub_lookup_count;
}
case HB_OT_TAG_GPOS:
{
return hb_ot_layout_from_face (face)->gpos_lookup_count;
}
}
return 0;
}
static void
_hb_ot_layout_collect_lookups_lookups (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
hb_set_t *lookup_indexes /* OUT */)
{
unsigned int lookup_indices[32];
unsigned int offset, len;
offset = 0;
do {
len = ARRAY_LENGTH (lookup_indices);
hb_ot_layout_feature_get_lookups (face,
table_tag,
feature_index,
offset, &len,
lookup_indices);
for (unsigned int i = 0; i < len; i++)
lookup_indexes->add (lookup_indices[i]);
offset += len;
} while (len == ARRAY_LENGTH (lookup_indices));
}
static void
_hb_ot_layout_collect_lookups_features (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
const hb_tag_t *features,
hb_set_t *lookup_indexes /* OUT */)
{
if (!features)
{
unsigned int required_feature_index;
if (hb_ot_layout_language_get_required_feature_index (face,
table_tag,
script_index,
language_index,
&required_feature_index))
_hb_ot_layout_collect_lookups_lookups (face,
table_tag,
required_feature_index,
lookup_indexes);
/* All features */
unsigned int feature_indices[32];
unsigned int offset, len;
offset = 0;
do {
len = ARRAY_LENGTH (feature_indices);
hb_ot_layout_language_get_feature_indexes (face,
table_tag,
script_index,
language_index,
offset, &len,
feature_indices);
for (unsigned int i = 0; i < len; i++)
_hb_ot_layout_collect_lookups_lookups (face,
table_tag,
feature_indices[i],
lookup_indexes);
offset += len;
} while (len == ARRAY_LENGTH (feature_indices));
}
else
{
for (; *features; features++)
{
unsigned int feature_index;
if (hb_ot_layout_language_find_feature (face,
table_tag,
script_index,
language_index,
*features,
&feature_index))
_hb_ot_layout_collect_lookups_lookups (face,
table_tag,
feature_index,
lookup_indexes);
}
}
}
static void
_hb_ot_layout_collect_lookups_languages (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
const hb_tag_t *languages,
const hb_tag_t *features,
hb_set_t *lookup_indexes /* OUT */)
{
_hb_ot_layout_collect_lookups_features (face,
table_tag,
script_index,
HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX,
features,
lookup_indexes);
if (!languages)
{
/* All languages */
unsigned int count = hb_ot_layout_script_get_language_tags (face,
table_tag,
script_index,
0, NULL, NULL);
for (unsigned int language_index = 0; language_index < count; language_index++)
_hb_ot_layout_collect_lookups_features (face,
table_tag,
script_index,
language_index,
features,
lookup_indexes);
}
else
{
for (; *languages; languages++)
{
unsigned int language_index;
if (hb_ot_layout_script_find_language (face,
table_tag,
script_index,
*languages,
&language_index))
_hb_ot_layout_collect_lookups_features (face,
table_tag,
script_index,
language_index,
features,
lookup_indexes);
}
}
}
void
hb_ot_layout_collect_lookups (hb_face_t *face,
hb_tag_t table_tag,
const hb_tag_t *scripts,
const hb_tag_t *languages,
const hb_tag_t *features,
hb_set_t *lookup_indexes /* OUT */)
{
if (!scripts)
{
/* All scripts */
unsigned int count = hb_ot_layout_table_get_script_tags (face,
table_tag,
0, NULL, NULL);
for (unsigned int script_index = 0; script_index < count; script_index++)
_hb_ot_layout_collect_lookups_languages (face,
table_tag,
script_index,
languages,
features,
lookup_indexes);
}
else
{
for (; *scripts; scripts++)
{
unsigned int script_index;
if (hb_ot_layout_table_find_script (face,
table_tag,
*scripts,
&script_index))
_hb_ot_layout_collect_lookups_languages (face,
table_tag,
script_index,
languages,
features,
lookup_indexes);
}
}
}
void
hb_ot_layout_lookup_collect_glyphs (hb_face_t *face,
hb_tag_t table_tag,
unsigned int lookup_index,
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 */)
{
if (unlikely (!hb_ot_shaper_face_data_ensure (face))) return;
OT::hb_collect_glyphs_context_t c (face,
glyphs_before,
glyphs_input,
glyphs_after,
glyphs_output);
switch (table_tag)
{
case HB_OT_TAG_GSUB:
{
const OT::SubstLookup& l = hb_ot_layout_from_face (face)->gsub->get_lookup (lookup_index);
l.collect_glyphs (&c);
return;
}
case HB_OT_TAG_GPOS:
{
const OT::PosLookup& l = hb_ot_layout_from_face (face)->gpos->get_lookup (lookup_index);
l.collect_glyphs (&c);
return;
}
}
}
/*
* OT::GSUB
*/
hb_bool_t
hb_ot_layout_has_substitution (hb_face_t *face)
{
return &_get_gsub (face) != &OT::Null(OT::GSUB);
}
hb_bool_t
hb_ot_layout_lookup_would_substitute (hb_face_t *face,
unsigned int lookup_index,
const hb_codepoint_t *glyphs,
unsigned int glyphs_length,
hb_bool_t zero_context)
{
if (unlikely (!hb_ot_shaper_face_data_ensure (face))) return false;
return hb_ot_layout_lookup_would_substitute_fast (face, lookup_index, glyphs, glyphs_length, zero_context);
}
hb_bool_t
hb_ot_layout_lookup_would_substitute_fast (hb_face_t *face,
unsigned int lookup_index,
const hb_codepoint_t *glyphs,
unsigned int glyphs_length,
hb_bool_t zero_context)
{
if (unlikely (lookup_index >= hb_ot_layout_from_face (face)->gsub_lookup_count)) return false;
OT::hb_would_apply_context_t c (face, glyphs, glyphs_length, zero_context);
const OT::SubstLookup& l = hb_ot_layout_from_face (face)->gsub->get_lookup (lookup_index);
return l.would_apply (&c, &hb_ot_layout_from_face (face)->gsub_accels[lookup_index].digest);
}
void
hb_ot_layout_substitute_start (hb_font_t *font, hb_buffer_t *buffer)
{
OT::GSUB::substitute_start (font, buffer);
}
void
hb_ot_layout_substitute_finish (hb_font_t *font, hb_buffer_t *buffer)
{
OT::GSUB::substitute_finish (font, buffer);
}
void
hb_ot_layout_lookup_substitute_closure (hb_face_t *face,
unsigned int lookup_index,
hb_set_t *glyphs)
{
OT::hb_closure_context_t c (face, glyphs);
const OT::SubstLookup& l = _get_gsub (face).get_lookup (lookup_index);
l.closure (&c);
}
/*
* OT::GPOS
*/
hb_bool_t
hb_ot_layout_has_positioning (hb_face_t *face)
{
return &_get_gpos (face) != &OT::Null(OT::GPOS);
}
void
hb_ot_layout_position_start (hb_font_t *font, hb_buffer_t *buffer)
{
OT::GPOS::position_start (font, buffer);
}
void
hb_ot_layout_position_finish (hb_font_t *font, hb_buffer_t *buffer)
{
OT::GPOS::position_finish (font, buffer);
}
hb_bool_t
hb_ot_layout_get_size_params (hb_face_t *face,
unsigned int *design_size, /* OUT. May be NULL */
unsigned int *subfamily_id, /* OUT. May be NULL */
unsigned int *subfamily_name_id, /* OUT. May be NULL */
unsigned int *range_start, /* OUT. May be NULL */
unsigned int *range_end /* OUT. May be NULL */)
{
const OT::GPOS &gpos = _get_gpos (face);
const hb_tag_t tag = HB_TAG ('s','i','z','e');
unsigned int num_features = gpos.get_feature_count ();
for (unsigned int i = 0; i < num_features; i++)
{
if (tag == gpos.get_feature_tag (i))
{
const OT::Feature &f = gpos.get_feature (i);
const OT::FeatureParamsSize ¶ms = f.get_feature_params ().get_size_params (tag);
if (params.designSize)
{
#define PARAM(a, A) if (a) *a = params.A
PARAM (design_size, designSize);
PARAM (subfamily_id, subfamilyID);
PARAM (subfamily_name_id, subfamilyNameID);
PARAM (range_start, rangeStart);
PARAM (range_end, rangeEnd);
#undef PARAM
return true;
}
}
}
#define PARAM(a, A) if (a) *a = 0
PARAM (design_size, designSize);
PARAM (subfamily_id, subfamilyID);
PARAM (subfamily_name_id, subfamilyNameID);
PARAM (range_start, rangeStart);
PARAM (range_end, rangeEnd);
#undef PARAM
return false;
}
/*
* Parts of different types are implemented here such that they have direct
* access to GSUB/GPOS lookups.
*/
struct GSUBProxy
{
static const unsigned int table_index = 0;
static const bool inplace = false;
typedef OT::SubstLookup Lookup;
GSUBProxy (hb_face_t *face) :
table (*hb_ot_layout_from_face (face)->gsub),
accels (hb_ot_layout_from_face (face)->gsub_accels) {}
const OT::GSUB &table;
const hb_ot_layout_lookup_accelerator_t *accels;
};
struct GPOSProxy
{
static const unsigned int table_index = 1;
static const bool inplace = true;
typedef OT::PosLookup Lookup;
GPOSProxy (hb_face_t *face) :
table (*hb_ot_layout_from_face (face)->gpos),
accels (hb_ot_layout_from_face (face)->gpos_accels) {}
const OT::GPOS &table;
const hb_ot_layout_lookup_accelerator_t *accels;
};
template <typename Lookup>
static inline bool apply_once (OT::hb_apply_context_t *c,
const Lookup &lookup)
{
if (!c->check_glyph_property (&c->buffer->cur(), c->lookup_props))
return false;
return lookup.dispatch (c);
}
template <typename Proxy>
static inline bool
apply_string (OT::hb_apply_context_t *c,
const typename Proxy::Lookup &lookup,
const hb_ot_layout_lookup_accelerator_t &accel)
{
bool ret = false;
hb_buffer_t *buffer = c->buffer;
if (unlikely (!buffer->len || !c->lookup_mask))
return false;
c->set_lookup (lookup);
if (likely (!lookup.is_reverse ()))
{
/* in/out forward substitution/positioning */
if (Proxy::table_index == 0)
buffer->clear_output ();
buffer->idx = 0;
while (buffer->idx < buffer->len)
{
if (accel.digest.may_have (buffer->cur().codepoint) &&
(buffer->cur().mask & c->lookup_mask) &&
apply_once (c, lookup))
ret = true;
else
buffer->next_glyph ();
}
if (ret)
{
if (!Proxy::inplace)
buffer->swap_buffers ();
else
assert (!buffer->has_separate_output ());
}
}
else
{
/* in-place backward substitution/positioning */
if (Proxy::table_index == 0)
buffer->remove_output ();
buffer->idx = buffer->len - 1;
do
{
if (accel.digest.may_have (buffer->cur().codepoint) &&
(buffer->cur().mask & c->lookup_mask) &&
apply_once (c, lookup))
ret = true;
/* The reverse lookup doesn't "advance" cursor (for good reason). */
buffer->idx--;
}
while ((int) buffer->idx >= 0);
}
return ret;
}
template <typename Proxy>
inline void hb_ot_map_t::apply (const Proxy &proxy,
const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer) const
{
const unsigned int table_index = proxy.table_index;
unsigned int i = 0;
OT::hb_apply_context_t c (table_index, font, buffer);
c.set_recurse_func (Proxy::Lookup::apply_recurse_func);
for (unsigned int stage_index = 0; stage_index < stages[table_index].len; stage_index++) {
const stage_map_t *stage = &stages[table_index][stage_index];
for (; i < stage->last_lookup; i++)
{
unsigned int lookup_index = lookups[table_index][i].index;
c.set_lookup_mask (lookups[table_index][i].mask);
c.set_auto_zwj (lookups[table_index][i].auto_zwj);
apply_string<Proxy> (&c,
proxy.table.get_lookup (lookup_index),
proxy.accels[lookup_index]);
}
if (stage->pause_func)
{
buffer->clear_output ();
stage->pause_func (plan, font, buffer);
}
}
}
void hb_ot_map_t::substitute (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const
{
GSUBProxy proxy (font->face);
apply (proxy, plan, font, buffer);
}
void hb_ot_map_t::position (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const
{
GPOSProxy proxy (font->face);
apply (proxy, plan, font, buffer);
}
HB_INTERNAL void
hb_ot_layout_substitute_lookup (OT::hb_apply_context_t *c,
const OT::SubstLookup &lookup,
const hb_ot_layout_lookup_accelerator_t &accel)
{
apply_string<GSUBProxy> (c, lookup, accel);
}