688 lines
21 KiB
C++
688 lines
21 KiB
C++
/*
|
|
* Copyright © 2018 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.
|
|
*
|
|
* Google Author(s): Garret Rieger, Rod Sheeter, Behdad Esfahbod
|
|
*/
|
|
|
|
#include "hb.hh"
|
|
#include "hb-open-type.hh"
|
|
|
|
#include "hb-subset.hh"
|
|
|
|
#include "hb-open-file.hh"
|
|
#include "hb-ot-cmap-table.hh"
|
|
#include "hb-ot-glyf-table.hh"
|
|
#include "hb-ot-hdmx-table.hh"
|
|
#include "hb-ot-head-table.hh"
|
|
#include "hb-ot-hhea-table.hh"
|
|
#include "hb-ot-hmtx-table.hh"
|
|
#include "hb-ot-maxp-table.hh"
|
|
#include "OT/Color/CBDT/CBDT.hh"
|
|
#include "OT/Color/COLR/COLR.hh"
|
|
#include "OT/Color/CPAL/CPAL.hh"
|
|
#include "OT/Color/sbix/sbix.hh"
|
|
#include "hb-ot-os2-table.hh"
|
|
#include "hb-ot-post-table.hh"
|
|
#include "hb-ot-post-table-v2subset.hh"
|
|
#include "hb-ot-cff1-table.hh"
|
|
#include "hb-ot-cff2-table.hh"
|
|
#include "hb-ot-vorg-table.hh"
|
|
#include "hb-ot-name-table.hh"
|
|
#include "hb-ot-layout-gsub-table.hh"
|
|
#include "hb-ot-layout-gpos-table.hh"
|
|
#include "hb-ot-var-avar-table.hh"
|
|
#include "hb-ot-var-cvar-table.hh"
|
|
#include "hb-ot-var-fvar-table.hh"
|
|
#include "hb-ot-var-gvar-table.hh"
|
|
#include "hb-ot-var-hvar-table.hh"
|
|
#include "hb-ot-math-table.hh"
|
|
#include "hb-ot-stat-table.hh"
|
|
#include "hb-repacker.hh"
|
|
#include "hb-subset-accelerator.hh"
|
|
|
|
using OT::Layout::GSUB;
|
|
using OT::Layout::GPOS;
|
|
|
|
|
|
#ifndef HB_NO_SUBSET_CFF
|
|
template<>
|
|
struct hb_subset_plan_t::source_table_loader<const OT::cff1>
|
|
{
|
|
auto operator () (hb_subset_plan_t *plan)
|
|
HB_AUTO_RETURN (plan->accelerator ? plan->accelerator->cff1_accel :
|
|
plan->inprogress_accelerator ? plan->inprogress_accelerator->cff1_accel :
|
|
plan->cff1_accel)
|
|
};
|
|
template<>
|
|
struct hb_subset_plan_t::source_table_loader<const OT::cff2>
|
|
{
|
|
auto operator () (hb_subset_plan_t *plan)
|
|
HB_AUTO_RETURN (plan->accelerator ? plan->accelerator->cff2_accel :
|
|
plan->inprogress_accelerator ? plan->inprogress_accelerator->cff2_accel :
|
|
plan->cff2_accel)
|
|
};
|
|
#endif
|
|
|
|
|
|
/**
|
|
* SECTION:hb-subset
|
|
* @title: hb-subset
|
|
* @short_description: Subsets font files.
|
|
* @include: hb-subset.h
|
|
*
|
|
* Subsetting reduces the codepoint coverage of font files and removes all data
|
|
* that is no longer needed. A subset input describes the desired subset. The input is
|
|
* provided along with a font to the subsetting operation. Output is a new font file
|
|
* containing only the data specified in the input.
|
|
*
|
|
* Currently most outline and bitmap tables are supported: glyf, CFF, CFF2, sbix,
|
|
* COLR, and CBDT/CBLC. This also includes fonts with variable outlines via OpenType
|
|
* variations. Notably EBDT/EBLC and SVG are not supported. Layout subsetting is supported
|
|
* only for OpenType Layout tables (GSUB, GPOS, GDEF). Notably subsetting of graphite or AAT tables
|
|
* is not yet supported.
|
|
*
|
|
* Fonts with graphite or AAT tables may still be subsetted but will likely need to use the
|
|
* retain glyph ids option and configure the subset to pass through the layout tables untouched.
|
|
*/
|
|
|
|
|
|
hb_user_data_key_t _hb_subset_accelerator_user_data_key = {};
|
|
|
|
|
|
/*
|
|
* The list of tables in the open type spec. Used to check for tables that may need handling
|
|
* if we are unable to list the tables in a face.
|
|
*/
|
|
static hb_tag_t known_tables[] {
|
|
HB_TAG ('a', 'v', 'a', 'r'),
|
|
HB_OT_TAG_BASE,
|
|
HB_OT_TAG_CBDT,
|
|
HB_OT_TAG_CBLC,
|
|
HB_OT_TAG_CFF1,
|
|
HB_OT_TAG_CFF2,
|
|
HB_OT_TAG_cmap,
|
|
HB_OT_TAG_COLR,
|
|
HB_OT_TAG_CPAL,
|
|
HB_TAG ('c', 'v', 'a', 'r'),
|
|
HB_TAG ('c', 'v', 't', ' '),
|
|
HB_TAG ('D', 'S', 'I', 'G'),
|
|
HB_TAG ('E', 'B', 'D', 'T'),
|
|
HB_TAG ('E', 'B', 'L', 'C'),
|
|
HB_TAG ('E', 'B', 'S', 'C'),
|
|
HB_TAG ('f', 'p', 'g', 'm'),
|
|
HB_TAG ('f', 'v', 'a', 'r'),
|
|
HB_TAG ('g', 'a', 's', 'p'),
|
|
HB_OT_TAG_GDEF,
|
|
HB_OT_TAG_glyf,
|
|
HB_OT_TAG_GPOS,
|
|
HB_OT_TAG_GSUB,
|
|
HB_OT_TAG_gvar,
|
|
HB_OT_TAG_hdmx,
|
|
HB_OT_TAG_head,
|
|
HB_OT_TAG_hhea,
|
|
HB_OT_TAG_hmtx,
|
|
HB_OT_TAG_HVAR,
|
|
HB_OT_TAG_JSTF,
|
|
HB_TAG ('k', 'e', 'r', 'n'),
|
|
HB_OT_TAG_loca,
|
|
HB_TAG ('L', 'T', 'S', 'H'),
|
|
HB_OT_TAG_MATH,
|
|
HB_OT_TAG_maxp,
|
|
HB_TAG ('M', 'E', 'R', 'G'),
|
|
HB_TAG ('m', 'e', 't', 'a'),
|
|
HB_TAG ('M', 'V', 'A', 'R'),
|
|
HB_TAG ('P', 'C', 'L', 'T'),
|
|
HB_OT_TAG_post,
|
|
HB_TAG ('p', 'r', 'e', 'p'),
|
|
HB_OT_TAG_sbix,
|
|
HB_TAG ('S', 'T', 'A', 'T'),
|
|
HB_TAG ('S', 'V', 'G', ' '),
|
|
HB_TAG ('V', 'D', 'M', 'X'),
|
|
HB_OT_TAG_vhea,
|
|
HB_OT_TAG_vmtx,
|
|
HB_OT_TAG_VORG,
|
|
HB_OT_TAG_VVAR,
|
|
HB_OT_TAG_name,
|
|
HB_OT_TAG_OS2
|
|
};
|
|
|
|
static bool _table_is_empty (const hb_face_t *face, hb_tag_t tag)
|
|
{
|
|
hb_blob_t* blob = hb_face_reference_table (face, tag);
|
|
bool result = (blob == hb_blob_get_empty ());
|
|
hb_blob_destroy (blob);
|
|
return result;
|
|
}
|
|
|
|
static unsigned int
|
|
_get_table_tags (const hb_subset_plan_t* plan,
|
|
unsigned int start_offset,
|
|
unsigned int *table_count, /* IN/OUT */
|
|
hb_tag_t *table_tags /* OUT */)
|
|
{
|
|
unsigned num_tables = hb_face_get_table_tags (plan->source, 0, nullptr, nullptr);
|
|
if (num_tables)
|
|
return hb_face_get_table_tags (plan->source, start_offset, table_count, table_tags);
|
|
|
|
// If face has 0 tables associated with it, assume that it was built from
|
|
// hb_face_create_tables and thus is unable to list its tables. Fallback to
|
|
// checking each table type we can handle for existence instead.
|
|
auto it =
|
|
hb_concat (
|
|
+ hb_array (known_tables)
|
|
| hb_filter ([&] (hb_tag_t tag) {
|
|
return !_table_is_empty (plan->source, tag) && !plan->no_subset_tables.has (tag);
|
|
})
|
|
| hb_map ([] (hb_tag_t tag) -> hb_tag_t { return tag; }),
|
|
|
|
plan->no_subset_tables.iter ()
|
|
| hb_filter([&] (hb_tag_t tag) {
|
|
return !_table_is_empty (plan->source, tag);
|
|
}));
|
|
|
|
it += start_offset;
|
|
|
|
unsigned num_written = 0;
|
|
while (bool (it) && num_written < *table_count)
|
|
table_tags[num_written++] = *it++;
|
|
|
|
*table_count = num_written;
|
|
return num_written;
|
|
}
|
|
|
|
|
|
static unsigned
|
|
_plan_estimate_subset_table_size (hb_subset_plan_t *plan,
|
|
unsigned table_len,
|
|
hb_tag_t table_tag)
|
|
{
|
|
unsigned src_glyphs = plan->source->get_num_glyphs ();
|
|
unsigned dst_glyphs = plan->glyphset ()->get_population ();
|
|
|
|
unsigned bulk = 8192;
|
|
/* Tables that we want to allocate same space as the source table. For GSUB/GPOS it's
|
|
* because those are expensive to subset, so giving them more room is fine. */
|
|
bool same_size = table_tag == HB_OT_TAG_GSUB ||
|
|
table_tag == HB_OT_TAG_GPOS ||
|
|
table_tag == HB_OT_TAG_name;
|
|
|
|
if (plan->flags & HB_SUBSET_FLAGS_RETAIN_GIDS)
|
|
{
|
|
if (table_tag == HB_OT_TAG_CFF1)
|
|
{
|
|
/* Add some extra room for the CFF charset. */
|
|
bulk += src_glyphs * 16;
|
|
}
|
|
else if (table_tag == HB_OT_TAG_CFF2)
|
|
{
|
|
/* Just extra CharString offsets. */
|
|
bulk += src_glyphs * 4;
|
|
}
|
|
}
|
|
|
|
if (unlikely (!src_glyphs) || same_size)
|
|
return bulk + table_len;
|
|
|
|
return bulk + (unsigned) (table_len * sqrt ((double) dst_glyphs / src_glyphs));
|
|
}
|
|
|
|
/*
|
|
* Repack the serialization buffer if any offset overflows exist.
|
|
*/
|
|
static hb_blob_t*
|
|
_repack (hb_tag_t tag, const hb_serialize_context_t& c)
|
|
{
|
|
if (!c.offset_overflow ())
|
|
return c.copy_blob ();
|
|
|
|
hb_blob_t* result = hb_resolve_overflows (c.object_graph (), tag);
|
|
|
|
if (unlikely (!result))
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "OT::%c%c%c%c offset overflow resolution failed.",
|
|
HB_UNTAG (tag));
|
|
return nullptr;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
template<typename TableType>
|
|
static
|
|
bool
|
|
_try_subset (const TableType *table,
|
|
hb_vector_t<char>* buf,
|
|
hb_subset_context_t* c /* OUT */)
|
|
{
|
|
c->serializer->start_serialize ();
|
|
if (c->serializer->in_error ()) return false;
|
|
|
|
bool needed = table->subset (c);
|
|
if (!c->serializer->ran_out_of_room ())
|
|
{
|
|
c->serializer->end_serialize ();
|
|
return needed;
|
|
}
|
|
|
|
unsigned buf_size = buf->allocated;
|
|
buf_size = buf_size * 2 + 16;
|
|
|
|
|
|
|
|
|
|
DEBUG_MSG (SUBSET, nullptr, "OT::%c%c%c%c ran out of room; reallocating to %u bytes.",
|
|
HB_UNTAG (c->table_tag), buf_size);
|
|
|
|
if (unlikely (buf_size > c->source_blob->length * 16 ||
|
|
!buf->alloc (buf_size, true)))
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "OT::%c%c%c%c failed to reallocate %u bytes.",
|
|
HB_UNTAG (c->table_tag), buf_size);
|
|
return needed;
|
|
}
|
|
|
|
c->serializer->reset (buf->arrayZ, buf->allocated);
|
|
return _try_subset (table, buf, c);
|
|
}
|
|
|
|
template <typename T>
|
|
static auto _do_destroy (T &t, hb_priority<1>) HB_RETURN (void, t.destroy ())
|
|
|
|
template <typename T>
|
|
static void _do_destroy (T &t, hb_priority<0>) {}
|
|
|
|
template<typename TableType>
|
|
static bool
|
|
_subset (hb_subset_plan_t *plan, hb_vector_t<char> &buf)
|
|
{
|
|
auto &&source_blob = plan->source_table<TableType> ();
|
|
auto *table = source_blob.get ();
|
|
|
|
hb_tag_t tag = TableType::tableTag;
|
|
hb_blob_t *blob = source_blob.get_blob();
|
|
if (unlikely (!blob || !blob->data))
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr,
|
|
"OT::%c%c%c%c::subset sanitize failed on source table.", HB_UNTAG (tag));
|
|
_do_destroy (source_blob, hb_prioritize);
|
|
return false;
|
|
}
|
|
|
|
unsigned buf_size = _plan_estimate_subset_table_size (plan, blob->length, TableType::tableTag);
|
|
DEBUG_MSG (SUBSET, nullptr,
|
|
"OT::%c%c%c%c initial estimated table size: %u bytes.", HB_UNTAG (tag), buf_size);
|
|
if (unlikely (!buf.alloc (buf_size)))
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "OT::%c%c%c%c failed to allocate %u bytes.", HB_UNTAG (tag), buf_size);
|
|
_do_destroy (source_blob, hb_prioritize);
|
|
return false;
|
|
}
|
|
|
|
bool needed = false;
|
|
hb_serialize_context_t serializer (buf.arrayZ, buf.allocated);
|
|
{
|
|
hb_subset_context_t c (blob, plan, &serializer, tag);
|
|
needed = _try_subset (table, &buf, &c);
|
|
}
|
|
_do_destroy (source_blob, hb_prioritize);
|
|
|
|
if (serializer.in_error () && !serializer.only_offset_overflow ())
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "OT::%c%c%c%c::subset FAILED!", HB_UNTAG (tag));
|
|
return false;
|
|
}
|
|
|
|
if (!needed)
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "OT::%c%c%c%c::subset table subsetted to empty.", HB_UNTAG (tag));
|
|
return true;
|
|
}
|
|
|
|
bool result = false;
|
|
hb_blob_t *dest_blob = _repack (tag, serializer);
|
|
if (dest_blob)
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr,
|
|
"OT::%c%c%c%c final subset table size: %u bytes.",
|
|
HB_UNTAG (tag), dest_blob->length);
|
|
result = plan->add_table (tag, dest_blob);
|
|
hb_blob_destroy (dest_blob);
|
|
}
|
|
|
|
DEBUG_MSG (SUBSET, nullptr, "OT::%c%c%c%c::subset %s",
|
|
HB_UNTAG (tag), result ? "success" : "FAILED!");
|
|
return result;
|
|
}
|
|
|
|
static bool
|
|
_is_table_present (hb_face_t *source, hb_tag_t tag)
|
|
{
|
|
|
|
if (!hb_face_get_table_tags (source, 0, nullptr, nullptr)) {
|
|
// If face has 0 tables associated with it, assume that it was built from
|
|
// hb_face_create_tables and thus is unable to list its tables. Fallback to
|
|
// checking if the blob associated with tag is empty.
|
|
return !_table_is_empty (source, tag);
|
|
}
|
|
|
|
hb_tag_t table_tags[32];
|
|
unsigned offset = 0, num_tables = ARRAY_LENGTH (table_tags);
|
|
while (((void) hb_face_get_table_tags (source, offset, &num_tables, table_tags), num_tables))
|
|
{
|
|
for (unsigned i = 0; i < num_tables; ++i)
|
|
if (table_tags[i] == tag)
|
|
return true;
|
|
offset += num_tables;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static bool
|
|
_should_drop_table (hb_subset_plan_t *plan, hb_tag_t tag)
|
|
{
|
|
if (plan->drop_tables.has (tag))
|
|
return true;
|
|
|
|
switch (tag)
|
|
{
|
|
case HB_TAG ('c','v','a','r'): /* hint table, fallthrough */
|
|
return plan->all_axes_pinned || (plan->flags & HB_SUBSET_FLAGS_NO_HINTING);
|
|
|
|
case HB_TAG ('c','v','t',' '): /* hint table, fallthrough */
|
|
case HB_TAG ('f','p','g','m'): /* hint table, fallthrough */
|
|
case HB_TAG ('p','r','e','p'): /* hint table, fallthrough */
|
|
case HB_TAG ('h','d','m','x'): /* hint table, fallthrough */
|
|
case HB_TAG ('V','D','M','X'): /* hint table, fallthrough */
|
|
return plan->flags & HB_SUBSET_FLAGS_NO_HINTING;
|
|
|
|
#ifdef HB_NO_SUBSET_LAYOUT
|
|
// Drop Layout Tables if requested.
|
|
case HB_OT_TAG_GDEF:
|
|
case HB_OT_TAG_GPOS:
|
|
case HB_OT_TAG_GSUB:
|
|
case HB_TAG ('m','o','r','x'):
|
|
case HB_TAG ('m','o','r','t'):
|
|
case HB_TAG ('k','e','r','x'):
|
|
case HB_TAG ('k','e','r','n'):
|
|
return true;
|
|
#endif
|
|
|
|
case HB_TAG ('a','v','a','r'):
|
|
case HB_TAG ('f','v','a','r'):
|
|
case HB_TAG ('g','v','a','r'):
|
|
case HB_OT_TAG_HVAR:
|
|
case HB_OT_TAG_VVAR:
|
|
case HB_TAG ('M','V','A','R'):
|
|
return plan->all_axes_pinned;
|
|
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
static bool
|
|
_passthrough (hb_subset_plan_t *plan, hb_tag_t tag)
|
|
{
|
|
hb_blob_t *source_table = hb_face_reference_table (plan->source, tag);
|
|
bool result = plan->add_table (tag, source_table);
|
|
hb_blob_destroy (source_table);
|
|
return result;
|
|
}
|
|
|
|
static bool
|
|
_dependencies_satisfied (hb_subset_plan_t *plan, hb_tag_t tag,
|
|
const hb_set_t &subsetted_tags,
|
|
const hb_set_t &pending_subset_tags)
|
|
{
|
|
switch (tag)
|
|
{
|
|
case HB_OT_TAG_hmtx:
|
|
case HB_OT_TAG_vmtx:
|
|
case HB_OT_TAG_maxp:
|
|
return !plan->normalized_coords || !pending_subset_tags.has (HB_OT_TAG_glyf);
|
|
default:
|
|
return true;
|
|
}
|
|
}
|
|
|
|
static bool
|
|
_subset_table (hb_subset_plan_t *plan,
|
|
hb_vector_t<char> &buf,
|
|
hb_tag_t tag)
|
|
{
|
|
if (plan->no_subset_tables.has (tag)) {
|
|
return _passthrough (plan, tag);
|
|
}
|
|
|
|
DEBUG_MSG (SUBSET, nullptr, "subset %c%c%c%c", HB_UNTAG (tag));
|
|
switch (tag)
|
|
{
|
|
case HB_OT_TAG_glyf: return _subset<const OT::glyf> (plan, buf);
|
|
case HB_OT_TAG_hdmx: return _subset<const OT::hdmx> (plan, buf);
|
|
case HB_OT_TAG_name: return _subset<const OT::name> (plan, buf);
|
|
case HB_OT_TAG_head:
|
|
if (_is_table_present (plan->source, HB_OT_TAG_glyf) && !_should_drop_table (plan, HB_OT_TAG_glyf))
|
|
return true; /* skip head, handled by glyf */
|
|
return _subset<const OT::head> (plan, buf);
|
|
case HB_OT_TAG_hhea: return true; /* skip hhea, handled by hmtx */
|
|
case HB_OT_TAG_hmtx: return _subset<const OT::hmtx> (plan, buf);
|
|
case HB_OT_TAG_vhea: return true; /* skip vhea, handled by vmtx */
|
|
case HB_OT_TAG_vmtx: return _subset<const OT::vmtx> (plan, buf);
|
|
case HB_OT_TAG_maxp: return _subset<const OT::maxp> (plan, buf);
|
|
case HB_OT_TAG_sbix: return _subset<const OT::sbix> (plan, buf);
|
|
case HB_OT_TAG_loca: return true; /* skip loca, handled by glyf */
|
|
case HB_OT_TAG_cmap: return _subset<const OT::cmap> (plan, buf);
|
|
case HB_OT_TAG_OS2 : return _subset<const OT::OS2 > (plan, buf);
|
|
case HB_OT_TAG_post: return _subset<const OT::post> (plan, buf);
|
|
case HB_OT_TAG_COLR: return _subset<const OT::COLR> (plan, buf);
|
|
case HB_OT_TAG_CPAL: return _subset<const OT::CPAL> (plan, buf);
|
|
case HB_OT_TAG_CBLC: return _subset<const OT::CBLC> (plan, buf);
|
|
case HB_OT_TAG_CBDT: return true; /* skip CBDT, handled by CBLC */
|
|
case HB_OT_TAG_MATH: return _subset<const OT::MATH> (plan, buf);
|
|
|
|
#ifndef HB_NO_SUBSET_CFF
|
|
case HB_OT_TAG_CFF1: return _subset<const OT::cff1> (plan, buf);
|
|
case HB_OT_TAG_CFF2: return _subset<const OT::cff2> (plan, buf);
|
|
case HB_OT_TAG_VORG: return _subset<const OT::VORG> (plan, buf);
|
|
#endif
|
|
|
|
#ifndef HB_NO_SUBSET_LAYOUT
|
|
case HB_OT_TAG_GDEF: return _subset<const OT::GDEF> (plan, buf);
|
|
case HB_OT_TAG_GSUB: return _subset<const GSUB> (plan, buf);
|
|
case HB_OT_TAG_GPOS: return _subset<const GPOS> (plan, buf);
|
|
case HB_OT_TAG_gvar: return _subset<const OT::gvar> (plan, buf);
|
|
case HB_OT_TAG_HVAR: return _subset<const OT::HVAR> (plan, buf);
|
|
case HB_OT_TAG_VVAR: return _subset<const OT::VVAR> (plan, buf);
|
|
#endif
|
|
case HB_OT_TAG_fvar:
|
|
if (plan->user_axes_location.is_empty ()) return _passthrough (plan, tag);
|
|
return _subset<const OT::fvar> (plan, buf);
|
|
case HB_OT_TAG_avar:
|
|
if (plan->user_axes_location.is_empty ()) return _passthrough (plan, tag);
|
|
return _subset<const OT::avar> (plan, buf);
|
|
case HB_OT_TAG_STAT:
|
|
if (!plan->user_axes_location.is_empty ()) return _subset<const OT::STAT> (plan, buf);
|
|
else return _passthrough (plan, tag);
|
|
|
|
case HB_TAG ('c', 'v', 't', ' '):
|
|
#ifndef HB_NO_VAR
|
|
if (_is_table_present (plan->source, HB_OT_TAG_cvar) &&
|
|
plan->normalized_coords && !plan->pinned_at_default)
|
|
{
|
|
auto &cvar = *plan->source->table.cvar;
|
|
return OT::cvar::add_cvt_and_apply_deltas (plan, cvar.get_tuple_var_data (), &cvar);
|
|
}
|
|
#endif
|
|
return _passthrough (plan, tag);
|
|
default:
|
|
if (plan->flags & HB_SUBSET_FLAGS_PASSTHROUGH_UNRECOGNIZED)
|
|
return _passthrough (plan, tag);
|
|
|
|
// Drop table
|
|
return true;
|
|
}
|
|
}
|
|
|
|
static void _attach_accelerator_data (hb_subset_plan_t* plan,
|
|
hb_face_t* face /* IN/OUT */)
|
|
{
|
|
if (!plan->inprogress_accelerator) return;
|
|
|
|
// Transfer the accelerator from the plan to us.
|
|
hb_subset_accelerator_t* accel = plan->inprogress_accelerator;
|
|
plan->inprogress_accelerator = nullptr;
|
|
|
|
if (accel->in_error ())
|
|
{
|
|
hb_subset_accelerator_t::destroy (accel);
|
|
return;
|
|
}
|
|
|
|
// Populate caches that need access to the final tables.
|
|
hb_blob_ptr_t<OT::cmap> cmap_ptr (hb_sanitize_context_t ().reference_table<OT::cmap> (face));
|
|
accel->cmap_cache = OT::cmap::create_filled_cache (cmap_ptr);
|
|
accel->destroy_cmap_cache = OT::SubtableUnicodesCache::destroy;
|
|
|
|
if (!hb_face_set_user_data(face,
|
|
hb_subset_accelerator_t::user_data_key(),
|
|
accel,
|
|
hb_subset_accelerator_t::destroy,
|
|
true))
|
|
hb_subset_accelerator_t::destroy (accel);
|
|
}
|
|
|
|
/**
|
|
* hb_subset_or_fail:
|
|
* @source: font face data to be subset.
|
|
* @input: input to use for the subsetting.
|
|
*
|
|
* Subsets a font according to provided input. Returns nullptr
|
|
* if the subset operation fails.
|
|
*
|
|
* Since: 2.9.0
|
|
**/
|
|
hb_face_t *
|
|
hb_subset_or_fail (hb_face_t *source, const hb_subset_input_t *input)
|
|
{
|
|
if (unlikely (!input || !source)) return hb_face_get_empty ();
|
|
|
|
hb_subset_plan_t *plan = hb_subset_plan_create_or_fail (source, input);
|
|
if (unlikely (!plan)) {
|
|
return nullptr;
|
|
}
|
|
|
|
hb_face_t * result = hb_subset_plan_execute_or_fail (plan);
|
|
hb_subset_plan_destroy (plan);
|
|
return result;
|
|
}
|
|
|
|
|
|
/**
|
|
* hb_subset_plan_execute_or_fail:
|
|
* @plan: a subsetting plan.
|
|
*
|
|
* Executes the provided subsetting @plan.
|
|
*
|
|
* Return value:
|
|
* on success returns a reference to generated font subset. If the subsetting operation fails
|
|
* returns nullptr.
|
|
*
|
|
* Since: 4.0.0
|
|
**/
|
|
hb_face_t *
|
|
hb_subset_plan_execute_or_fail (hb_subset_plan_t *plan)
|
|
{
|
|
if (unlikely (!plan || plan->in_error ())) {
|
|
return nullptr;
|
|
}
|
|
|
|
hb_tag_t table_tags[32];
|
|
unsigned offset = 0, num_tables = ARRAY_LENGTH (table_tags);
|
|
|
|
hb_set_t subsetted_tags, pending_subset_tags;
|
|
while (((void) _get_table_tags (plan, offset, &num_tables, table_tags), num_tables))
|
|
{
|
|
for (unsigned i = 0; i < num_tables; ++i)
|
|
{
|
|
hb_tag_t tag = table_tags[i];
|
|
if (_should_drop_table (plan, tag)) continue;
|
|
pending_subset_tags.add (tag);
|
|
}
|
|
|
|
offset += num_tables;
|
|
}
|
|
|
|
bool success = true;
|
|
|
|
{
|
|
// Grouping to deallocate buf before calling hb_face_reference (plan->dest).
|
|
|
|
hb_vector_t<char> buf;
|
|
buf.alloc (8192 - 16);
|
|
|
|
while (!pending_subset_tags.is_empty ())
|
|
{
|
|
if (subsetted_tags.in_error ()
|
|
|| pending_subset_tags.in_error ()) {
|
|
success = false;
|
|
goto end;
|
|
}
|
|
|
|
bool made_changes = false;
|
|
for (hb_tag_t tag : pending_subset_tags)
|
|
{
|
|
if (!_dependencies_satisfied (plan, tag,
|
|
subsetted_tags,
|
|
pending_subset_tags))
|
|
{
|
|
// delayed subsetting for some tables since they might have dependency on other tables
|
|
// in some cases: e.g: during instantiating glyf tables, hmetrics/vmetrics are updated
|
|
// and saved in subset plan, hmtx/vmtx subsetting need to use these updated metrics values
|
|
continue;
|
|
}
|
|
|
|
pending_subset_tags.del (tag);
|
|
subsetted_tags.add (tag);
|
|
made_changes = true;
|
|
|
|
success = _subset_table (plan, buf, tag);
|
|
if (unlikely (!success)) goto end;
|
|
}
|
|
|
|
if (!made_changes)
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "Table dependencies unable to be satisfied. Subset failed.");
|
|
success = false;
|
|
goto end;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (success && plan->attach_accelerator_data) {
|
|
_attach_accelerator_data (plan, plan->dest);
|
|
}
|
|
|
|
end:
|
|
return success ? hb_face_reference (plan->dest) : nullptr;
|
|
}
|