harfbuzz/src/hb-ot-layout.cc

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/*
* 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-open-type.hh"
#include "hb-ot-layout.hh"
#include "hb-ot-face.hh"
#include "hb-ot-map.hh"
#include "hb-map.hh"
#include "hb-ot-kern-table.hh"
#include "hb-ot-gasp-table.hh" // Just so we compile it; unused otherwise.
#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-base-table.hh" // Just so we compile it; unused otherwise.
#include "hb-ot-layout-jstf-table.hh" // Just so we compile it; unused otherwise.
#include "hb-ot-name-table.hh"
#include "hb-ot-os2-table.hh"
#include "hb-aat-layout-lcar-table.hh"
#include "hb-aat-layout-morx-table.hh"
/**
* SECTION:hb-ot-layout
* @title: hb-ot-layout
* @short_description: OpenType Layout
* @include: hb-ot.h
*
* Functions for querying OpenType Layout features in the font face.
**/
/*
* kern
*/
/**
* hb_ot_layout_has_kerning:
* @face: The #hb_face_t to work on
*
* Tests whether a face includes any kerning data in the 'kern' table.
* Does NOT test for kerning lookups in the GPOS table.
*
* Return value: true if data found, false otherwise
*
**/
bool
hb_ot_layout_has_kerning (hb_face_t *face)
{
return face->table.kern->has_data ();
}
/**
* hb_ot_layout_has_machine_kerning:
* @face: The #hb_face_t to work on
*
* Tests whether a face includes any state-machine kerning in the 'kern' table.
* Does NOT examine the GPOS table.
*
* Return value: true if data found, false otherwise
*
**/
bool
hb_ot_layout_has_machine_kerning (hb_face_t *face)
{
return face->table.kern->has_state_machine ();
}
/**
* hb_ot_layout_has_cross_kerning:
* @face: The #hb_face_t to work on
*
* Tests whether a face has any cross-stream kerning (i.e., kerns
* that make adjustments perpendicular to the direction of the text
* flow: Y adjustments in horizontal text or X adjustments in
* vertical text) in the 'kern' table.
*
* Does NOT examine the GPOS table.
*
* Return value: true is data found, false otherwise
*
**/
bool
hb_ot_layout_has_cross_kerning (hb_face_t *face)
{
return face->table.kern->has_cross_stream ();
}
void
hb_ot_layout_kern (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer)
{
hb_blob_t *blob = font->face->table.kern.get_blob ();
const AAT::kern& kern = *blob->as<AAT::kern> ();
AAT::hb_aat_apply_context_t c (plan, font, buffer, blob);
kern.apply (&c);
}
/*
* GDEF
*/
bool
OT::GDEF::is_blacklisted (hb_blob_t *blob,
hb_face_t *face) const
{
#ifdef HB_NO_OT_LAYOUT_BLACKLIST
return false;
#endif
/* The ugly business of blacklisting individual fonts' tables happen here!
* See this thread for why we finally had to bend in and do this:
* https://lists.freedesktop.org/archives/harfbuzz/2016-February/005489.html
*
* In certain versions of Times New Roman Italic and Bold Italic,
* ASCII double quotation mark U+0022 has wrong glyph class 3 (mark)
* in GDEF. Many versions of Tahoma have bad GDEF tables that
* incorrectly classify some spacing marks such as certain IPA
* symbols as glyph class 3. So do older versions of Microsoft
* Himalaya, and the version of Cantarell shipped by Ubuntu 16.04.
*
* Nuke the GDEF tables of to avoid unwanted width-zeroing.
*
* See https://bugzilla.mozilla.org/show_bug.cgi?id=1279925
* https://bugzilla.mozilla.org/show_bug.cgi?id=1279693
* https://bugzilla.mozilla.org/show_bug.cgi?id=1279875
*/
switch HB_CODEPOINT_ENCODE3(blob->length,
face->table.GSUB->table.get_length (),
face->table.GPOS->table.get_length ())
{
/* sha1sum:c5ee92f0bca4bfb7d06c4d03e8cf9f9cf75d2e8a Windows 7? timesi.ttf */
case HB_CODEPOINT_ENCODE3 (442, 2874, 42038):
/* sha1sum:37fc8c16a0894ab7b749e35579856c73c840867b Windows 7? timesbi.ttf */
case HB_CODEPOINT_ENCODE3 (430, 2874, 40662):
/* sha1sum:19fc45110ea6cd3cdd0a5faca256a3797a069a80 Windows 7 timesi.ttf */
case HB_CODEPOINT_ENCODE3 (442, 2874, 39116):
/* sha1sum:6d2d3c9ed5b7de87bc84eae0df95ee5232ecde26 Windows 7 timesbi.ttf */
case HB_CODEPOINT_ENCODE3 (430, 2874, 39374):
/* sha1sum:8583225a8b49667c077b3525333f84af08c6bcd8 OS X 10.11.3 Times New Roman Italic.ttf */
case HB_CODEPOINT_ENCODE3 (490, 3046, 41638):
/* sha1sum:ec0f5a8751845355b7c3271d11f9918a966cb8c9 OS X 10.11.3 Times New Roman Bold Italic.ttf */
case HB_CODEPOINT_ENCODE3 (478, 3046, 41902):
/* sha1sum:96eda93f7d33e79962451c6c39a6b51ee893ce8c tahoma.ttf from Windows 8 */
case HB_CODEPOINT_ENCODE3 (898, 12554, 46470):
/* sha1sum:20928dc06014e0cd120b6fc942d0c3b1a46ac2bc tahomabd.ttf from Windows 8 */
case HB_CODEPOINT_ENCODE3 (910, 12566, 47732):
/* sha1sum:4f95b7e4878f60fa3a39ca269618dfde9721a79e tahoma.ttf from Windows 8.1 */
case HB_CODEPOINT_ENCODE3 (928, 23298, 59332):
/* sha1sum:6d400781948517c3c0441ba42acb309584b73033 tahomabd.ttf from Windows 8.1 */
case HB_CODEPOINT_ENCODE3 (940, 23310, 60732):
/* tahoma.ttf v6.04 from Windows 8.1 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */
case HB_CODEPOINT_ENCODE3 (964, 23836, 60072):
/* tahomabd.ttf v6.04 from Windows 8.1 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */
case HB_CODEPOINT_ENCODE3 (976, 23832, 61456):
/* sha1sum:e55fa2dfe957a9f7ec26be516a0e30b0c925f846 tahoma.ttf from Windows 10 */
case HB_CODEPOINT_ENCODE3 (994, 24474, 60336):
/* sha1sum:7199385abb4c2cc81c83a151a7599b6368e92343 tahomabd.ttf from Windows 10 */
case HB_CODEPOINT_ENCODE3 (1006, 24470, 61740):
/* tahoma.ttf v6.91 from Windows 10 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */
case HB_CODEPOINT_ENCODE3 (1006, 24576, 61346):
/* tahomabd.ttf v6.91 from Windows 10 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */
case HB_CODEPOINT_ENCODE3 (1018, 24572, 62828):
/* sha1sum:b9c84d820c49850d3d27ec498be93955b82772b5 tahoma.ttf from Windows 10 AU */
case HB_CODEPOINT_ENCODE3 (1006, 24576, 61352):
/* sha1sum:2bdfaab28174bdadd2f3d4200a30a7ae31db79d2 tahomabd.ttf from Windows 10 AU */
case HB_CODEPOINT_ENCODE3 (1018, 24572, 62834):
/* sha1sum:b0d36cf5a2fbe746a3dd277bffc6756a820807a7 Tahoma.ttf from Mac OS X 10.9 */
case HB_CODEPOINT_ENCODE3 (832, 7324, 47162):
/* sha1sum:12fc4538e84d461771b30c18b5eb6bd434e30fba Tahoma Bold.ttf from Mac OS X 10.9 */
case HB_CODEPOINT_ENCODE3 (844, 7302, 45474):
/* sha1sum:eb8afadd28e9cf963e886b23a30b44ab4fd83acc himalaya.ttf from Windows 7 */
case HB_CODEPOINT_ENCODE3 (180, 13054, 7254):
/* sha1sum:73da7f025b238a3f737aa1fde22577a6370f77b0 himalaya.ttf from Windows 8 */
case HB_CODEPOINT_ENCODE3 (192, 12638, 7254):
/* sha1sum:6e80fd1c0b059bbee49272401583160dc1e6a427 himalaya.ttf from Windows 8.1 */
case HB_CODEPOINT_ENCODE3 (192, 12690, 7254):
/* 8d9267aea9cd2c852ecfb9f12a6e834bfaeafe44 cantarell-fonts-0.0.21/otf/Cantarell-Regular.otf */
/* 983988ff7b47439ab79aeaf9a45bd4a2c5b9d371 cantarell-fonts-0.0.21/otf/Cantarell-Oblique.otf */
case HB_CODEPOINT_ENCODE3 (188, 248, 3852):
/* 2c0c90c6f6087ffbfea76589c93113a9cbb0e75f cantarell-fonts-0.0.21/otf/Cantarell-Bold.otf */
/* 55461f5b853c6da88069ffcdf7f4dd3f8d7e3e6b cantarell-fonts-0.0.21/otf/Cantarell-Bold-Oblique.otf */
case HB_CODEPOINT_ENCODE3 (188, 264, 3426):
/* d125afa82a77a6475ac0e74e7c207914af84b37a padauk-2.80/Padauk.ttf RHEL 7.2 */
case HB_CODEPOINT_ENCODE3 (1058, 47032, 11818):
/* 0f7b80437227b90a577cc078c0216160ae61b031 padauk-2.80/Padauk-Bold.ttf RHEL 7.2*/
case HB_CODEPOINT_ENCODE3 (1046, 47030, 12600):
/* d3dde9aa0a6b7f8f6a89ef1002e9aaa11b882290 padauk-2.80/Padauk.ttf Ubuntu 16.04 */
case HB_CODEPOINT_ENCODE3 (1058, 71796, 16770):
/* 5f3c98ccccae8a953be2d122c1b3a77fd805093f padauk-2.80/Padauk-Bold.ttf Ubuntu 16.04 */
case HB_CODEPOINT_ENCODE3 (1046, 71790, 17862):
/* 6c93b63b64e8b2c93f5e824e78caca555dc887c7 padauk-2.80/Padauk-book.ttf */
case HB_CODEPOINT_ENCODE3 (1046, 71788, 17112):
/* d89b1664058359b8ec82e35d3531931125991fb9 padauk-2.80/Padauk-bookbold.ttf */
case HB_CODEPOINT_ENCODE3 (1058, 71794, 17514):
/* 824cfd193aaf6234b2b4dc0cf3c6ef576c0d00ef padauk-3.0/Padauk-book.ttf */
case HB_CODEPOINT_ENCODE3 (1330, 109904, 57938):
/* 91fcc10cf15e012d27571e075b3b4dfe31754a8a padauk-3.0/Padauk-bookbold.ttf */
case HB_CODEPOINT_ENCODE3 (1330, 109904, 58972):
/* sha1sum: c26e41d567ed821bed997e937bc0c41435689e85 Padauk.ttf
* "Padauk Regular" "Version 2.5", see https://crbug.com/681813 */
case HB_CODEPOINT_ENCODE3 (1004, 59092, 14836):
return true;
}
return false;
}
static void
_hb_ot_layout_set_glyph_props (hb_font_t *font,
hb_buffer_t *buffer)
{
_hb_buffer_assert_gsubgpos_vars (buffer);
const OT::GDEF &gdef = *font->face->table.GDEF->table;
unsigned int count = buffer->len;
for (unsigned int i = 0; i < count; i++)
{
_hb_glyph_info_set_glyph_props (&buffer->info[i], gdef.get_glyph_props (buffer->info[i].codepoint));
_hb_glyph_info_clear_lig_props (&buffer->info[i]);
buffer->info[i].syllable() = 0;
}
}
/* Public API */
/**
* hb_ot_layout_has_glyph_classes:
* @face: #hb_face_t to work upon
*
* Tests whether a face has any glyph classes defined in its GDEF table.
*
* Return value: true if data found, false otherwise
*
**/
hb_bool_t
hb_ot_layout_has_glyph_classes (hb_face_t *face)
{
return face->table.GDEF->table->has_glyph_classes ();
}
/**
* hb_ot_layout_get_glyph_class:
* @face: The #hb_face_t to work on
* @glyph: The #hb_codepoint_t code point to query
*
* Fetches the GDEF class of the requested glyph in the specified face.
*
* Return value: The #hb_ot_layout_glyph_class_t glyph class of the given code
* point in the GDEF table of the face.
*
* Since: 0.9.7
**/
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) face->table.GDEF->table->get_glyph_class (glyph);
}
/**
* hb_ot_layout_get_glyphs_in_class:
* @face: The #hb_face_t to work on
* @klass: The #hb_ot_layout_glyph_class_t GDEF class to retrieve
* @glyphs: (out): The #hb_set_t set of all glyphs belonging to the requested
* class.
*
* Retrieves the set of all glyphs from the face that belong to the requested
* glyph class in the face's GDEF table.
*
* Since: 0.9.7
**/
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 face->table.GDEF->table->get_glyphs_in_class (klass, glyphs);
}
#ifndef HB_NO_LAYOUT_UNUSED
/**
* hb_ot_layout_get_attach_points:
* @face: The #hb_face_t to work on
* @glyph: The #hb_codepoint_t code point to query
* @start_offset: offset of the first attachment point to retrieve
* @point_count: (inout) (allow-none): Input = the maximum number of attachment points to return;
* Output = the actual number of attachment points returned (may be zero)
* @point_array: (out) (array length=point_count): The array of attachment points found for the query
*
* Fetches a list of all attachment points for the specified glyph in the GDEF
* table of the face. The list returned will begin at the offset provided.
*
* Useful if the client program wishes to cache the list.
*
**/
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 face->table.GDEF->table->get_attach_points (glyph,
start_offset,
point_count,
point_array);
}
/**
* hb_ot_layout_get_ligature_carets:
* @font: The #hb_font_t to work on
* @direction: The #hb_direction_t text direction to use
* @glyph: The #hb_codepoint_t code point to query
* @start_offset: offset of the first caret position to retrieve
* @caret_count: (inout) (allow-none): Input = the maximum number of caret positions to return;
* Output = the actual number of caret positions returned (may be zero)
* @caret_array: (out) (array length=caret_count): The array of caret positions found for the query
*
* Fetches a list of the caret positions defined for a ligature glyph in the GDEF
* table of the font. The list returned will begin at the offset provided.
*
**/
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 */,
hb_position_t *caret_array /* OUT */)
{
unsigned int result_caret_count = 0;
unsigned int result = font->face->table.GDEF->table->get_lig_carets (font, direction, glyph, start_offset, &result_caret_count, caret_array);
if (result)
{
if (caret_count) *caret_count = result_caret_count;
}
#ifndef HB_NO_AAT
else
result = font->face->table.lcar->get_lig_carets (font, direction, glyph, start_offset, caret_count, caret_array);
#endif
return result;
}
#endif
/*
* GSUB/GPOS
*/
bool
OT::GSUB::is_blacklisted (hb_blob_t *blob HB_UNUSED,
hb_face_t *face) const
{
#ifdef HB_NO_OT_LAYOUT_BLACKLIST
return false;
#endif
#ifndef HB_NO_SHAPE_AAT
/* Mac OS X prefers morx over GSUB. It also ships with various Indic fonts,
* all by 'MUTF' foundry (Tamil MN, Tamil Sangam MN, etc.), that have broken
* GSUB/GPOS tables. Some have GSUB with zero scripts, those are ignored by
* our morx/GSUB preference code. But if GSUB has non-zero scripts, we tend
* to prefer it over morx because we want to be consistent with other OpenType
* shapers.
*
* To work around broken Indic Mac system fonts, we ignore GSUB table if
* OS/2 VendorId is 'MUTF' and font has morx table as well.
*
* https://github.com/harfbuzz/harfbuzz/issues/1410
* https://github.com/harfbuzz/harfbuzz/issues/1348
* https://github.com/harfbuzz/harfbuzz/issues/1391
*/
if (unlikely (face->table.OS2->achVendID == HB_TAG ('M','U','T','F') &&
face->table.morx->has_data ()))
return true;
#endif
return false;
}
bool
OT::GPOS::is_blacklisted (hb_blob_t *blob HB_UNUSED,
hb_face_t *face HB_UNUSED) const
{
#ifdef HB_NO_OT_LAYOUT_BLACKLIST
return false;
#endif
return false;
}
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 *face->table.GSUB->table;
case HB_OT_TAG_GPOS: return *face->table.GPOS->table;
default: return Null(OT::GSUBGPOS);
}
}
/**
* hb_ot_layout_table_get_script_tags:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @start_offset: offset of the first script tag to retrieve
* @script_count: (inout) (allow-none): Input = the maximum number of script tags to return;
* Output = the actual number of script tags returned (may be zero)
* @script_tags: (out) (array length=script_count): The array of #hb_tag_t script tags found for the query
*
* Fetches a list of all scripts enumerated in the specified face's GSUB table
* or GPOS table. The list returned will begin at the offset provided.
*
**/
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_ot_layout_table_find_script:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_tag: #hb_tag_t of the script tag requested
* @script_index: (out): The index of the requested script tag
*
* Fetches the index if a given script tag in the specified face's GSUB table
* or GPOS table.
*
* Return value: true if the script is found, false otherwise
*
**/
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 /* OUT */)
{
static_assert ((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;
}
#ifndef HB_DISABLE_DEPRECATED
/**
* hb_ot_layout_table_choose_script:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_tags: Array of #hb_tag_t script tags
* @script_index: (out): The index of the requested script tag
* @chosen_script: (out): #hb_tag_t of the script tag requested
*
* Deprecated since 2.0.0
**/
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 /* OUT */,
hb_tag_t *chosen_script /* OUT */)
{
const hb_tag_t *t;
for (t = script_tags; *t; t++);
return hb_ot_layout_table_select_script (face, table_tag, t - script_tags, script_tags, script_index, chosen_script);
}
#endif
/**
* hb_ot_layout_table_select_script:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_count: Number of script tags in the array
* @script_tags: Array of #hb_tag_t script tags
* @script_index: (out): The index of the requested script
* @chosen_script: (out): #hb_tag_t of the requested script
*
* Since: 2.0.0
**/
hb_bool_t
hb_ot_layout_table_select_script (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_count,
const hb_tag_t *script_tags,
unsigned int *script_index /* OUT */,
hb_tag_t *chosen_script /* OUT */)
{
static_assert ((OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX), "");
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
unsigned int i;
for (i = 0; i < script_count; i++)
{
if (g.find_script_index (script_tags[i], script_index))
{
if (chosen_script)
*chosen_script = script_tags[i];
return true;
}
}
/* 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;
}
/**
* hb_ot_layout_table_get_feature_tags:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @start_offset: offset of the first feature tag to retrieve
* @feature_count: (inout) (allow-none): Input = the maximum number of feature tags to return;
* Output = the actual number of feature tags returned (may be zero)
* @feature_tags: (out) (array length=feature_count): Array of feature tags found in the table
*
* Fetches a list of all feature tags in the given face's GSUB or GPOS table.
*
**/
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);
}
/**
* hb_ot_layout_table_find_feature:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @feature_tag: The #hb_tag_t og the requested feature tag
* @feature_index: (out): The index of the requested feature
*
* Fetches the index for a given feature tag in the specified face's GSUB table
* or GPOS table.
*
* Return value: true if the feature is found, false otherwise
**/
bool
hb_ot_layout_table_find_feature (hb_face_t *face,
hb_tag_t table_tag,
hb_tag_t feature_tag,
unsigned int *feature_index /* OUT */)
{
static_assert ((OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_FEATURE_INDEX), "");
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
unsigned int num_features = g.get_feature_count ();
for (unsigned int i = 0; i < num_features; i++)
{
if (feature_tag == g.get_feature_tag (i)) {
if (feature_index) *feature_index = i;
return true;
}
}
if (feature_index) *feature_index = HB_OT_LAYOUT_NO_FEATURE_INDEX;
return false;
}
/**
* hb_ot_layout_script_get_language_tags:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_index: The index of the requested script tag
* @start_offset: offset of the first language tag to retrieve
* @language_count: (inout) (allow-none): Input = the maximum number of language tags to return;
* Output = the actual number of language tags returned (may be zero)
* @language_tags: (out) (array length=language_count): Array of language tags found in the table
*
* Fetches a list of language tags in the given face's GSUB or GPOS table, underneath
* the specified script index. The list returned will begin at the offset provided.
*
**/
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);
}
#ifndef HB_DISABLE_DEPRECATED
/**
* hb_ot_layout_script_find_language:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_index: The index of the requested script tag
* @language_tag: The #hb_tag_t of the requested language
* @language_index: The index of the requested language
*
* Fetches the index of a given language tag in the specified face's GSUB table
* or GPOS table, underneath the specified script tag.
*
* Return value: true if the language tag is found, false otherwise
*
* Since: ??
* Deprecated: ??
**/
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)
{
return hb_ot_layout_script_select_language (face,
table_tag,
script_index,
1,
&language_tag,
language_index);
}
#endif
/**
* hb_ot_layout_script_select_language:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_index: The index of the requested script tag
* @language_count: The number of languages in the specified script
* @language_tags: The array of language tags
* @language_index: (out): The index of the requested language
*
* Fetches the index of a given language tag in the specified face's GSUB table
* or GPOS table, underneath the specified script index.
*
* Return value: true if the language tag is found, false otherwise
*
* Since: 2.0.0
**/
hb_bool_t
hb_ot_layout_script_select_language (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_count,
const hb_tag_t *language_tags,
unsigned int *language_index /* OUT */)
{
static_assert ((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);
unsigned int i;
for (i = 0; i < language_count; i++)
{
if (s.find_lang_sys_index (language_tags[i], language_index))
return true;
}
/* try finding 'dflt' */
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_ot_layout_language_get_required_feature_index:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_index: The index of the requested script tag
* @language_index: The index of the requested language tag
* @feature_index: (out): The index of the requested feature
*
* Fetches the index of a requested feature in the given face's GSUB or GPOS table,
* underneath the specified script and language.
*
* Return value: true if the feature is found, false otherwise
*
**/
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)
{
return hb_ot_layout_language_get_required_feature (face,
table_tag,
script_index,
language_index,
feature_index,
nullptr);
}
/**
* hb_ot_layout_language_get_required_feature:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_index: The index of the requested script tag
* @language_index: The index of the requested language tag
* @feature_index: The index of the requested feature
* @feature_tag: (out): The #hb_tag_t of the requested feature
*
* Fetches the tag of a requested feature index in the given face's GSUB or GPOS table,
* underneath the specified script and language.
*
* Return value: true if the feature is found, false otherwise
*
* Since: 0.9.30
**/
hb_bool_t
hb_ot_layout_language_get_required_feature (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
unsigned int *feature_index,
hb_tag_t *feature_tag)
{
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 index = l.get_required_feature_index ();
if (feature_index) *feature_index = index;
if (feature_tag) *feature_tag = g.get_feature_tag (index);
return l.has_required_feature ();
}
/**
* hb_ot_layout_language_get_feature_indexes:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_index: The index of the requested script tag
* @language_index: The index of the requested language tag
* @start_offset: offset of the first feature tag to retrieve
* @feature_count: (inout) (allow-none): Input = the maximum number of feature tags to return;
* Output: the actual number of feature tags returned (may be zero)
* @feature_indexes: (out) (array length=feature_count): The array of feature indexes found for the query
*
* Fetches a list of all features in the specified face's GSUB table
* or GPOS table, underneath the specified script and language. The list
* returned will begin at the offset provided.
**/
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);
}
/**
* hb_ot_layout_language_get_feature_tags:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_index: The index of the requested script tag
* @language_index: The index of the requested language tag
* @start_offset: offset of the first feature tag to retrieve
* @feature_count: (inout) (allow-none): Input = the maximum number of feature tags to return;
* Output = the actual number of feature tags returned (may be zero)
* @feature_tags: (out) (array length=feature_count): The array of #hb_tag_t feature tags found for the query
*
* Fetches a list of all features in the specified face's GSUB table
* or GPOS table, underneath the specified script and language. The list
* returned will begin at the offset provided.
*
**/
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);
static_assert ((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_ot_layout_language_find_feature:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @script_index: The index of the requested script tag
* @language_index: The index of the requested language tag
* @feature_tag: #hb_tag_t of the feature tag requested
* @feature_index: (out): The index of the requested feature
*
* Fetches the index of a given feature tag in the specified face's GSUB table
* or GPOS table, underneath the specified script and language.
*
* Return value: true if the feature is found, false otherwise
*
**/
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 /* OUT */)
{
static_assert ((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;
}
/**
* hb_ot_layout_feature_get_lookups:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @feature_index: The index of the requested feature
* @start_offset: offset of the first lookup to retrieve
* @lookup_count: (inout) (allow-none): Input = the maximum number of lookups to return;
* Output = the actual number of lookups returned (may be zero)
* @lookup_indexes: (out) (array length=lookup_count): The array of lookup indexes found for the query
*
* Fetches a list of all lookups enumerated for the specified feature, in
* the specified face's GSUB table or GPOS table. The list returned will
* begin at the offset provided.
*
* Since: 0.9.7
**/
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 */)
{
return hb_ot_layout_feature_with_variations_get_lookups (face,
table_tag,
feature_index,
HB_OT_LAYOUT_NO_VARIATIONS_INDEX,
start_offset,
lookup_count,
lookup_indexes);
}
/**
* hb_ot_layout_table_get_lookup_count:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
*
* Fetches the total number of lookups enumerated in the specified
* face's GSUB table or GPOS table.
*
* Since: 0.9.22
**/
unsigned int
hb_ot_layout_table_get_lookup_count (hb_face_t *face,
hb_tag_t table_tag)
{
return get_gsubgpos_table (face, table_tag).get_lookup_count ();
}
struct hb_collect_features_context_t
{
hb_collect_features_context_t (hb_face_t *face,
hb_tag_t table_tag,
hb_set_t *feature_indexes_)
: g (get_gsubgpos_table (face, table_tag)),
feature_indexes (feature_indexes_),
script_count(0),langsys_count(0) {}
bool visited (const OT::Script &s)
{
/* We might have Null() object here. Don't want to involve
* that in the memoize. So, detect empty objects and return. */
if (unlikely (!s.has_default_lang_sys () &&
!s.get_lang_sys_count ()))
return true;
if (script_count++ > HB_MAX_SCRIPTS)
return true;
return visited (s, visited_script);
}
bool visited (const OT::LangSys &l)
{
/* We might have Null() object here. Don't want to involve
* that in the memoize. So, detect empty objects and return. */
if (unlikely (!l.has_required_feature () &&
!l.get_feature_count ()))
return true;
if (langsys_count++ > HB_MAX_LANGSYS)
return true;
return visited (l, visited_langsys);
}
private:
template <typename T>
bool visited (const T &p, hb_set_t &visited_set)
{
hb_codepoint_t delta = (hb_codepoint_t) ((uintptr_t) &p - (uintptr_t) &g);
if (visited_set.has (delta))
return true;
visited_set.add (delta);
return false;
}
public:
const OT::GSUBGPOS &g;
hb_set_t *feature_indexes;
private:
hb_set_t visited_script;
hb_set_t visited_langsys;
unsigned int script_count;
unsigned int langsys_count;
};
static void
langsys_collect_features (hb_collect_features_context_t *c,
const OT::LangSys &l,
const hb_tag_t *features)
{
if (c->visited (l)) return;
if (!features)
{
/* All features. */
if (l.has_required_feature ())
c->feature_indexes->add (l.get_required_feature_index ());
l.add_feature_indexes_to (c->feature_indexes);
}
else
{
/* Ugh. Any faster way? */
for (; *features; features++)
{
hb_tag_t feature_tag = *features;
unsigned int num_features = l.get_feature_count ();
for (unsigned int i = 0; i < num_features; i++)
{
unsigned int feature_index = l.get_feature_index (i);
if (feature_tag == c->g.get_feature_tag (feature_index))
{
c->feature_indexes->add (feature_index);
break;
}
}
}
}
}
static void
script_collect_features (hb_collect_features_context_t *c,
const OT::Script &s,
const hb_tag_t *languages,
const hb_tag_t *features)
{
if (c->visited (s)) return;
if (!languages)
{
/* All languages. */
if (s.has_default_lang_sys ())
langsys_collect_features (c,
s.get_default_lang_sys (),
features);
unsigned int count = s.get_lang_sys_count ();
for (unsigned int language_index = 0; language_index < count; language_index++)
langsys_collect_features (c,
s.get_lang_sys (language_index),
features);
}
else
{
for (; *languages; languages++)
{
unsigned int language_index;
if (s.find_lang_sys_index (*languages, &language_index))
langsys_collect_features (c,
s.get_lang_sys (language_index),
features);
}
}
}
/**
* hb_ot_layout_collect_features:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @scripts: The array of scripts to collect features for
* @languages: The array of languages to collect features for
* @features: The array of features to collect
* @feature_indexes: (out): The array of feature indexes found for the query
*
* Fetches a list of all feature indexes in the specified face's GSUB table
* or GPOS table, underneath the specified scripts, languages, and features.
* If no list of scripts is provided, all scripts will be queried. If no list
* of languages is provided, all languages will be queried. If no list of
* features is provided, all features will be queried.
*
* Since: 1.8.5
**/
void
hb_ot_layout_collect_features (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 *feature_indexes /* OUT */)
{
hb_collect_features_context_t c (face, table_tag, feature_indexes);
if (!scripts)
{
/* All scripts. */
unsigned int count = c.g.get_script_count ();
for (unsigned int script_index = 0; script_index < count; script_index++)
script_collect_features (&c,
c.g.get_script (script_index),
languages,
features);
}
else
{
for (; *scripts; scripts++)
{
unsigned int script_index;
if (c.g.find_script_index (*scripts, &script_index))
script_collect_features (&c,
c.g.get_script (script_index),
languages,
features);
}
}
}
/**
* hb_ot_layout_collect_lookups:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @scripts: The array of scripts to collect lookups for
* @languages: The array of languages to collect lookups for
* @features: The array of features to collect lookups for
* @lookup_indexes: (out): The array of lookup indexes found for the query
*
* Fetches a list of all feature-lookup indexes in the specified face's GSUB
* table or GPOS table, underneath the specified scripts, languages, and
* features. If no list of scripts is provided, all scripts will be queried.
* If no list of languages is provided, all languages will be queried. If no
* list of features is provided, all features will be queried.
*
* Since: 0.9.8
**/
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 */)
{
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
hb_set_t feature_indexes;
hb_ot_layout_collect_features (face, table_tag, scripts, languages, features, &feature_indexes);
for (hb_codepoint_t feature_index = HB_SET_VALUE_INVALID;
hb_set_next (&feature_indexes, &feature_index);)
g.get_feature (feature_index).add_lookup_indexes_to (lookup_indexes);
}
/**
* hb_ot_layout_lookup_collect_glyphs:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @lookup_index: The index of the feature lookup to query
* @glyphs_before: (out): Array of glyphs preceding the substitution range
* @glyphs_input: (out): Array of input glyphs that would be substituted by the lookup
* @glyphs_after: (out): Array of glyphs following the substition range
* @glyphs_output: (out): Array of glyphs that would be the substitued output of the lookup
*
* Fetches a list of all glyphs affected by the specified lookup in the
* specified face's GSUB table of GPOS table.
*
* Since: 0.9.7
**/
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 */)
{
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 = face->table.GSUB->table->get_lookup (lookup_index);
l.collect_glyphs (&c);
return;
}
case HB_OT_TAG_GPOS:
{
const OT::PosLookup& l = face->table.GPOS->table->get_lookup (lookup_index);
l.collect_glyphs (&c);
return;
}
}
}
/* Variations support */
/**
* hb_ot_layout_table_find_feature_variations:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @coords: The variation coordinates to query
* @num_coords: The number of variation coorinates
* @variations_index: (out): The array of feature variations found for the query
*
* Fetches a list of feature variations in the specified face's GSUB table
* or GPOS table, at the specified variation coordinates.
*
**/
hb_bool_t
hb_ot_layout_table_find_feature_variations (hb_face_t *face,
hb_tag_t table_tag,
const int *coords,
unsigned int num_coords,
unsigned int *variations_index /* out */)
{
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
return g.find_variations_index (coords, num_coords, variations_index);
}
/**
* hb_ot_layout_feature_with_variations_get_lookups:
* @face: #hb_face_t to work upon
* @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
* @feature_index: The index of the feature to query
* @variations_index: The index of the feature variation to query
* @start_offset: offset of the first lookup to retrieve
* @lookup_count: (inout) (allow-none): Input = the maximum number of lookups to return;
* Output = the actual number of lookups returned (may be zero)
* @lookup_indexes: (out) (array length=lookup_count): The array of lookups found for the query
*
* Fetches a list of all lookups enumerated for the specified feature, in
* the specified face's GSUB table or GPOS table, enabled at the specified
* variations index. The list returned will begin at the offset provided.
*
**/
unsigned int
hb_ot_layout_feature_with_variations_get_lookups (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
unsigned int variations_index,
unsigned int start_offset,
unsigned int *lookup_count /* IN/OUT */,
unsigned int *lookup_indexes /* OUT */)
{
static_assert ((OT::FeatureVariations::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_VARIATIONS_INDEX), "");
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
const OT::Feature &f = g.get_feature_variation (feature_index, variations_index);
return f.get_lookup_indexes (start_offset, lookup_count, lookup_indexes);
}
/*
* OT::GSUB
*/
/**
* hb_ot_layout_has_substitution:
* @face: #hb_face_t to work upon
*
* Tests whether the specified face includes any GSUB substitutions.
*
* Return value: true if data found, false otherwise
*
**/
hb_bool_t
hb_ot_layout_has_substitution (hb_face_t *face)
{
return face->table.GSUB->table->has_data ();
}
/**
* hb_ot_layout_lookup_would_substitute:
* @face: #hb_face_t to work upon
* @lookup_index: The index of the lookup to query
* @glyphs: The sequence of glyphs to query for substitution
* @glyphs_length: The length of the glyph sequence
* @zero_context: #hb_bool_t indicating whether substitutions should be context-free
*
* Tests whether a specified lookup in the specified face would
* trigger a substitution on the given glyph sequence.
*
* Return value: true if a substitution would be triggered, false otherwise
*
* Since: 0.9.7
**/
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 (lookup_index >= face->table.GSUB->lookup_count)) return false;
OT::hb_would_apply_context_t c (face, glyphs, glyphs_length, (bool) zero_context);
const OT::SubstLookup& l = face->table.GSUB->table->get_lookup (lookup_index);
return l.would_apply (&c, &face->table.GSUB->accels[lookup_index]);
}
/**
* hb_ot_layout_substitute_start:
* @font: #hb_font_t to use
* @buffer: #hb_buffer_t buffer to work upon
*
* Called before substitution lookups are performed, to ensure that glyph
* class and other properties are set on the glyphs in the buffer.
*
**/
void
hb_ot_layout_substitute_start (hb_font_t *font,
hb_buffer_t *buffer)
{
_hb_ot_layout_set_glyph_props (font, buffer);
}
void
hb_ot_layout_delete_glyphs_inplace (hb_buffer_t *buffer,
bool (*filter) (const hb_glyph_info_t *info))
{
/* Merge clusters and delete filtered glyphs.
* NOTE! We can't use out-buffer as we have positioning data. */
unsigned int j = 0;
unsigned int count = buffer->len;
hb_glyph_info_t *info = buffer->info;
hb_glyph_position_t *pos = buffer->pos;
for (unsigned int i = 0; i < count; i++)
{
if (filter (&info[i]))
{
/* Merge clusters.
* Same logic as buffer->delete_glyph(), but for in-place removal. */
unsigned int cluster = info[i].cluster;
if (i + 1 < count && cluster == info[i + 1].cluster)
continue; /* Cluster survives; do nothing. */
if (j)
{
/* Merge cluster backward. */
if (cluster < info[j - 1].cluster)
{
unsigned int mask = info[i].mask;
unsigned int old_cluster = info[j - 1].cluster;
for (unsigned k = j; k && info[k - 1].cluster == old_cluster; k--)
buffer->set_cluster (info[k - 1], cluster, mask);
}
continue;
}
if (i + 1 < count)
buffer->merge_clusters (i, i + 2); /* Merge cluster forward. */
continue;
}
if (j != i)
{
info[j] = info[i];
pos[j] = pos[i];
}
j++;
}
buffer->len = j;
}
/**
* hb_ot_layout_lookup_substitute_closure:
* @face: #hb_face_t to work upon
* @lookup_index: index of the feature lookup to query
* @glyphs: (out): Array of glyphs comprising the transitive closure of the lookup
*
* Compute the transitive closure of glyphs needed for a
* specified lookup.
*
* Since: 0.9.7
**/
void
hb_ot_layout_lookup_substitute_closure (hb_face_t *face,
unsigned int lookup_index,
hb_set_t *glyphs /* OUT */)
{
hb_map_t done_lookups;
OT::hb_closure_context_t c (face, glyphs, &done_lookups);
const OT::SubstLookup& l = face->table.GSUB->table->get_lookup (lookup_index);
l.closure (&c, lookup_index);
}
/**
* hb_ot_layout_lookups_substitute_closure:
* @face: #hb_face_t to work upon
* @lookups: The set of lookups to query
* @glyphs: (out): Array of glyphs comprising the transitive closure of the lookups
*
* Compute the transitive closure of glyphs needed for all of the
* provided lookups.
*
* Since: 1.8.1
**/
void
hb_ot_layout_lookups_substitute_closure (hb_face_t *face,
const hb_set_t *lookups,
hb_set_t *glyphs /* OUT */)
{
hb_map_t done_lookups;
OT::hb_closure_context_t c (face, glyphs, &done_lookups);
const OT::GSUB& gsub = *face->table.GSUB->table;
unsigned int iteration_count = 0;
unsigned int glyphs_length;
do
{
glyphs_length = glyphs->get_population ();
if (lookups != nullptr)
{
for (hb_codepoint_t lookup_index = HB_SET_VALUE_INVALID; hb_set_next (lookups, &lookup_index);)
gsub.get_lookup (lookup_index).closure (&c, lookup_index);
}
else
{
for (unsigned int i = 0; i < gsub.get_lookup_count (); i++)
gsub.get_lookup (i).closure (&c, i);
}
} while (iteration_count++ <= HB_CLOSURE_MAX_STAGES &&
glyphs_length != glyphs->get_population ());
}
/*
* OT::GPOS
*/
/**
* hb_ot_layout_has_positioning:
* @face: #hb_face_t to work upon
*
* Return value: true if the face has GPOS data, false otherwise
*
**/
hb_bool_t
hb_ot_layout_has_positioning (hb_face_t *face)
{
return face->table.GPOS->table->has_data ();
}
/**
* hb_ot_layout_position_start:
* @font: #hb_font_t to use
* @buffer: #hb_buffer_t buffer to work upon
*
* Called before positioning lookups are performed, to ensure that glyph
* attachment types and glyph-attachment chains are set for the glyphs in the buffer.
*
**/
void
hb_ot_layout_position_start (hb_font_t *font, hb_buffer_t *buffer)
{
OT::GPOS::position_start (font, buffer);
}
/**
* hb_ot_layout_position_finish_advances:
* @font: #hb_font_t to use
* @buffer: #hb_buffer_t buffer to work upon
*
* Called after positioning lookups are performed, to finish glyph advances.
*
**/
void
hb_ot_layout_position_finish_advances (hb_font_t *font, hb_buffer_t *buffer)
{
OT::GPOS::position_finish_advances (font, buffer);
}
/**
* hb_ot_layout_position_finish_offsets:
* @font: #hb_font_t to use
* @buffer: #hb_buffer_t buffer to work upon
*
* Called after positioning lookups are performed, to finish glyph offsets.
*
**/
void
hb_ot_layout_position_finish_offsets (hb_font_t *font, hb_buffer_t *buffer)
{
OT::GPOS::position_finish_offsets (font, buffer);
}
/**
* hb_ot_layout_get_size_params:
* @face: #hb_face_t to work upon
* @design_size: (out): The design size of the face
* @subfamily_id: (out): The identifier of the face within the font subfamily
* @subfamily_name_id: (out): The name table name ID of the face within the font subfamily
* @range_start: (out): The minimum size of the recommended size range for the face
* @range_end: (out): The maximum size of the recommended size range for the face
*
* Fetches optical-size feature data (i.e., the `size` feature from GPOS). Note that
* the subfamily_id and the subfamily name string (accessible via the subfamily_name_id)
* as used here are defined as pertaining only to fonts within a font family that differ
* specifically in their respective size ranges; other ways to differentiate fonts within
* a subfamily are not covered by the `size` feature.
*
* For more information on this distinction, see the `size` documentation at
* https://docs.microsoft.com/en-us/typography/opentype/spec/features_pt#tag-39size39
*
* Return value: true if data found, false otherwise
*
* Since: 0.9.10
**/
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 */
hb_ot_name_id_t *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 = *face->table.GPOS->table;
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 &params = f.get_feature_params ().get_size_params (tag);
if (params.designSize)
{
if (design_size) *design_size = params.designSize;
if (subfamily_id) *subfamily_id = params.subfamilyID;
if (subfamily_name_id) *subfamily_name_id = params.subfamilyNameID;
if (range_start) *range_start = params.rangeStart;
if (range_end) *range_end = params.rangeEnd;
return true;
}
}
}
if (design_size) *design_size = 0;
if (subfamily_id) *subfamily_id = 0;
if (subfamily_name_id) *subfamily_name_id = HB_OT_NAME_ID_INVALID;
if (range_start) *range_start = 0;
if (range_end) *range_end = 0;
return false;
}
/**
* hb_ot_layout_feature_get_name_ids:
* @face: #hb_face_t to work upon
* @table_tag: table tag to query, "GSUB" or "GPOS".
* @feature_index: index of feature to query.
* @label_id: (out) (allow-none): The name table name ID that specifies a string
* for a user-interface label for this feature. (May be NULL.)
* @tooltip_id: (out) (allow-none): The name table name ID that specifies a string
* that an application can use for tooltip text for this
* feature. (May be NULL.)
* @sample_id: (out) (allow-none): The name table name ID that specifies sample text
* that illustrates the effect of this feature. (May be NULL.)
* @num_named_parameters: (out) (allow-none): Number of named parameters. (May be zero.)
* @first_param_id: (out) (allow-none): The first name table name ID used to specify
* strings for user-interface labels for the feature
* parameters. (Must be zero if numParameters is zero.)
*
* Fetches name indices from feature parameters for "Stylistic Set" ('ssXX') or
* "Character Variant" ('cvXX') features.
*
* Return value: true if data found, false otherwise
*
* Since: 2.0.0
**/
hb_bool_t
hb_ot_layout_feature_get_name_ids (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
hb_ot_name_id_t *label_id, /* OUT. May be NULL */
hb_ot_name_id_t *tooltip_id, /* OUT. May be NULL */
hb_ot_name_id_t *sample_id, /* OUT. May be NULL */
unsigned int *num_named_parameters, /* OUT. May be NULL */
hb_ot_name_id_t *first_param_id /* OUT. May be NULL */)
{
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
hb_tag_t feature_tag = g.get_feature_tag (feature_index);
const OT::Feature &f = g.get_feature (feature_index);
const OT::FeatureParams &feature_params = f.get_feature_params ();
if (&feature_params != &Null (OT::FeatureParams))
{
const OT::FeatureParamsStylisticSet& ss_params =
feature_params.get_stylistic_set_params (feature_tag);
if (&ss_params != &Null (OT::FeatureParamsStylisticSet)) /* ssXX */
{
if (label_id) *label_id = ss_params.uiNameID;
// ssXX features don't have the rest
if (tooltip_id) *tooltip_id = HB_OT_NAME_ID_INVALID;
if (sample_id) *sample_id = HB_OT_NAME_ID_INVALID;
if (num_named_parameters) *num_named_parameters = 0;
if (first_param_id) *first_param_id = HB_OT_NAME_ID_INVALID;
return true;
}
const OT::FeatureParamsCharacterVariants& cv_params =
feature_params.get_character_variants_params (feature_tag);
if (&cv_params != &Null (OT::FeatureParamsCharacterVariants)) /* cvXX */
{
if (label_id) *label_id = cv_params.featUILableNameID;
if (tooltip_id) *tooltip_id = cv_params.featUITooltipTextNameID;
if (sample_id) *sample_id = cv_params.sampleTextNameID;
if (num_named_parameters) *num_named_parameters = cv_params.numNamedParameters;
if (first_param_id) *first_param_id = cv_params.firstParamUILabelNameID;
return true;
}
}
if (label_id) *label_id = HB_OT_NAME_ID_INVALID;
if (tooltip_id) *tooltip_id = HB_OT_NAME_ID_INVALID;
if (sample_id) *sample_id = HB_OT_NAME_ID_INVALID;
if (num_named_parameters) *num_named_parameters = 0;
if (first_param_id) *first_param_id = HB_OT_NAME_ID_INVALID;
return false;
}
/**
* hb_ot_layout_feature_get_characters:
* @face: #hb_face_t to work upon
* @table_tag: table tag to query, "GSUB" or "GPOS".
* @feature_index: index of feature to query.
* @start_offset: offset of the first character to retrieve
* @char_count: (inout) (allow-none): Input = the maximum number of characters to return;
* Output = the actual number of characters returned (may be zero)
* @characters: (out caller-allocates) (array length=char_count): A buffer pointer.
* The Unicode codepoints of the characters for which this feature provides
* glyph variants.
*
* Fetches a list of the characters defined as having a variant under the specified
* "Character Variant" ("cvXX") feature tag.
*
* <note>Note: If the char_count output value is equal to its input value, then there
* is a chance there were more characters defined under the feature tag than were
* returned. This function can be called with incrementally larger start_offset
* until the char_count output value is lower than its input value, or the size
* of the characters array can be increased.</note>
*
* Return value: Number of total sample characters in the cvXX feature.
*
* Since: 2.0.0
**/
unsigned int
hb_ot_layout_feature_get_characters (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
unsigned int start_offset,
unsigned int *char_count, /* IN/OUT. May be NULL */
hb_codepoint_t *characters /* OUT. May be NULL */)
{
const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
hb_tag_t feature_tag = g.get_feature_tag (feature_index);
const OT::Feature &f = g.get_feature (feature_index);
const OT::FeatureParams &feature_params = f.get_feature_params ();
const OT::FeatureParamsCharacterVariants& cv_params =
feature_params.get_character_variants_params(feature_tag);
unsigned int len = 0;
if (char_count && characters && start_offset < cv_params.characters.len)
{
len = hb_min (cv_params.characters.len - start_offset, *char_count);
for (unsigned int i = 0; i < len; ++i)
characters[i] = cv_params.characters[start_offset + i];
}
if (char_count) *char_count = len;
return cv_params.characters.len;
}
/*
* Parts of different types are implemented here such that they have direct
* access to GSUB/GPOS lookups.
*/
struct GSUBProxy
{
static constexpr unsigned table_index = 0u;
static constexpr bool inplace = false;
typedef OT::SubstLookup Lookup;
GSUBProxy (hb_face_t *face) :
table (*face->table.GSUB->table),
accels (face->table.GSUB->accels) {}
const OT::GSUB &table;
const OT::hb_ot_layout_lookup_accelerator_t *accels;
};
struct GPOSProxy
{
static constexpr unsigned table_index = 1u;
static constexpr bool inplace = true;
typedef OT::PosLookup Lookup;
GPOSProxy (hb_face_t *face) :
table (*face->table.GPOS->table),
accels (face->table.GPOS->accels) {}
const OT::GPOS &table;
const OT::hb_ot_layout_lookup_accelerator_t *accels;
};
static inline bool
apply_forward (OT::hb_ot_apply_context_t *c,
const OT::hb_ot_layout_lookup_accelerator_t &accel)
{
bool ret = false;
hb_buffer_t *buffer = c->buffer;
while (buffer->idx < buffer->len && buffer->successful)
{
bool applied = false;
if (accel.may_have (buffer->cur().codepoint) &&
(buffer->cur().mask & c->lookup_mask) &&
c->check_glyph_property (&buffer->cur(), c->lookup_props))
{
applied = accel.apply (c);
}
if (applied)
ret = true;
else
buffer->next_glyph ();
}
return ret;
}
static inline bool
apply_backward (OT::hb_ot_apply_context_t *c,
const OT::hb_ot_layout_lookup_accelerator_t &accel)
{
bool ret = false;
hb_buffer_t *buffer = c->buffer;
do
{
if (accel.may_have (buffer->cur().codepoint) &&
(buffer->cur().mask & c->lookup_mask) &&
c->check_glyph_property (&buffer->cur(), c->lookup_props))
ret |= accel.apply (c);
/* The reverse lookup doesn't "advance" cursor (for good reason). */
buffer->idx--;
}
while ((int) buffer->idx >= 0);
return ret;
}
template <typename Proxy>
static inline void
apply_string (OT::hb_ot_apply_context_t *c,
const typename Proxy::Lookup &lookup,
const OT::hb_ot_layout_lookup_accelerator_t &accel)
{
hb_buffer_t *buffer = c->buffer;
if (unlikely (!buffer->len || !c->lookup_mask))
return;
c->set_lookup_props (lookup.get_props ());
if (likely (!lookup.is_reverse ()))
{
/* in/out forward substitution/positioning */
if (Proxy::table_index == 0u)
buffer->clear_output ();
buffer->idx = 0;
bool ret;
ret = apply_forward (c, accel);
if (ret)
{
if (!Proxy::inplace)
buffer->swap_buffers ();
else
assert (!buffer->has_separate_output ());
}
}
else
{
/* in-place backward substitution/positioning */
if (Proxy::table_index == 0u)
buffer->remove_output ();
buffer->idx = buffer->len - 1;
apply_backward (c, accel);
}
}
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_ot_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].length; 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;
if (!buffer->message (font, "start lookup %d", lookup_index)) continue;
c.set_lookup_index (lookup_index);
c.set_lookup_mask (lookups[table_index][i].mask);
c.set_auto_zwj (lookups[table_index][i].auto_zwj);
c.set_auto_zwnj (lookups[table_index][i].auto_zwnj);
if (lookups[table_index][i].random)
{
c.set_random (true);
buffer->unsafe_to_break_all ();
}
apply_string<Proxy> (&c,
proxy.table.get_lookup (lookup_index),
proxy.accels[lookup_index]);
(void) buffer->message (font, "end lookup %d", 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);
}
void
hb_ot_layout_substitute_lookup (OT::hb_ot_apply_context_t *c,
const OT::SubstLookup &lookup,
const OT::hb_ot_layout_lookup_accelerator_t &accel)
{
apply_string<GSUBProxy> (c, lookup, accel);
}
#if 0
hb_bool_t
hb_ot_layout_get_baseline (hb_font_t *font,
hb_ot_layout_baseline_t baseline,
hb_direction_t direction,
hb_tag_t script_tag,
hb_tag_t language_tag,
hb_position_t *coord /* OUT. May be NULL. */)
{
bool result = font->face->table.BASE->get_baseline (font, baseline, direction, script_tag,
language_tag, coord);
/* TODO: Simulate https://docs.microsoft.com/en-us/typography/opentype/spec/baselinetags#ideographic-em-box */
if (!result && coord) *coord = 0;
if (coord) *coord = font->em_scale_dir (*coord, direction);
return result;
}
/* To be moved to public header */
/*
* BASE
*/
/**
* hb_ot_layout_baseline_t:
*
* https://docs.microsoft.com/en-us/typography/opentype/spec/baselinetags
*
* Since: DONTREPLACEME
*/
typedef enum {
HB_OT_LAYOUT_BASELINE_HANG = HB_TAG('h','a','n','g'),
HB_OT_LAYOUT_BASELINE_ICFB = HB_TAG('i','c','f','b'),
HB_OT_LAYOUT_BASELINE_ICFT = HB_TAG('i','c','f','t'),
HB_OT_LAYOUT_BASELINE_IDEO = HB_TAG('i','d','e','o'),
HB_OT_LAYOUT_BASELINE_IDTB = HB_TAG('i','d','t','b'),
HB_OT_LAYOUT_BASELINE_MATH = HB_TAG('m','a','t','h'),
HB_OT_LAYOUT_BASELINE_ROMN = HB_TAG('r','o','m','n')
} hb_ot_layout_baseline_t;
/**
* hb_ot_layout_get_baseline:
* @font: The #hb_font_t to work upon
* @baseline: The #hb_ot_layout_baseline_t to query
* @direction: The #hb_direction_t text direction to use (horizontal or vertical)
* @script_tag: #hb_tag_t of the script to use
* @language_tag: #hb_tag_t of the language to use
* @coord: (out): The position of the requested baseline
*
* Fetches the coordinates of the specified baseline in the face, underneath
* the specified script and language and in the specified text direction.
*
* Return value: true if the baseline is found for the settings queried, false otherwise
*
**/
HB_EXTERN hb_bool_t
hb_ot_layout_get_baseline (hb_font_t *font,
hb_ot_layout_baseline_t baseline,
hb_direction_t direction,
hb_tag_t script_tag,
hb_tag_t language_tag,
hb_position_t *coord /* OUT. May be NULL. */);
#endif