[subset] cache cp to new gid list in subset plan.

This avoids having to recompute the ordered list multiple times during cmap generation.
This commit is contained in:
Garret Rieger 2022-05-02 21:29:16 +00:00
parent a4522df378
commit 088133d939
3 changed files with 32 additions and 8 deletions

View File

@ -332,7 +332,6 @@ struct CmapSubtableFormat4
if (unlikely (!c->extend_min (this))) return;
this->format = 4;
// TODO(grieger): does pre-alloc make this faster?
hb_vector_t<hb_pair_t<hb_codepoint_t, hb_codepoint_t>> cp_to_gid {
format4_iter
};
@ -1664,13 +1663,7 @@ struct cmap
if (unlikely (has_format12 && (!unicode_ucs4 && !ms_ucs4))) return_trace (false);
auto it =
+ hb_iter (c->plan->unicodes)
| hb_map ([&] (hb_codepoint_t _)
{
hb_codepoint_t new_gid = HB_MAP_VALUE_INVALID;
c->plan->new_gid_for_codepoint (_, &new_gid);
return hb_pair_t<hb_codepoint_t, hb_codepoint_t> (_, new_gid);
})
+ c->plan->unicode_to_new_gid_list->iter ()
| hb_filter ([&] (const hb_pair_t<hb_codepoint_t, hb_codepoint_t> _)
{ return (_.second != HB_MAP_VALUE_INVALID); })
;

View File

@ -287,6 +287,14 @@ _remove_invalid_gids (hb_set_t *glyphs,
}
}
static inline int
_compare_cp_gid_pair (const void* a,
const void* b)
{
return ((hb_pair_t<hb_codepoint_t, hb_codepoint_t>*)a)->first -
((hb_pair_t<hb_codepoint_t, hb_codepoint_t>*)b)->first;
}
static void
_populate_unicodes_to_retain (const hb_set_t *unicodes,
const hb_set_t *glyphs,
@ -300,6 +308,7 @@ _populate_unicodes_to_retain (const hb_set_t *unicodes,
{
/* This is the fast path if it's anticipated that size of unicodes
* is << than the number of codepoints in the font. */
plan->unicode_to_new_gid_list->alloc (unicodes->get_population ());
for (hb_codepoint_t cp : *unicodes)
{
hb_codepoint_t gid;
@ -310,12 +319,14 @@ _populate_unicodes_to_retain (const hb_set_t *unicodes,
}
plan->codepoint_to_glyph->set (cp, gid);
plan->unicode_to_new_gid_list->push (hb_pair (cp, gid));
}
}
else
{
hb_map_t unicode_glyphid_map;
cmap.collect_mapping (hb_set_get_empty (), &unicode_glyphid_map);
plan->unicode_to_new_gid_list->alloc (unicode_glyphid_map.get_population ());
for (hb_pair_t<hb_codepoint_t, hb_codepoint_t> cp_gid :
+ unicode_glyphid_map.iter ())
@ -324,8 +335,11 @@ _populate_unicodes_to_retain (const hb_set_t *unicodes,
continue;
plan->codepoint_to_glyph->set (cp_gid.first, cp_gid.second);
plan->unicode_to_new_gid_list->push (hb_pair (cp_gid.first, cp_gid.second));
}
plan->unicode_to_new_gid_list->qsort (_compare_cp_gid_pair);
/* Add gids which where requested, but not mapped in cmap */
// TODO(garretrieger):
// Once https://github.com/harfbuzz/harfbuzz/issues/3169
@ -485,6 +499,10 @@ hb_subset_plan_create_or_fail (hb_face_t *face,
plan->successful = true;
plan->flags = input->flags;
plan->unicodes = hb_set_create ();
plan->unicode_to_new_gid_list =
(hb_vector_t<hb_pair_t<hb_codepoint_t, hb_codepoint_t>>*)
hb_calloc (1, sizeof(hb_vector_t<hb_pair_t<hb_codepoint_t, hb_codepoint_t>>));
plan->unicode_to_new_gid_list->init ();
plan->name_ids = hb_set_copy (input->sets.name_ids);
_nameid_closure (face, plan->name_ids);
plan->name_languages = hb_set_copy (input->sets.name_languages);
@ -536,6 +554,13 @@ hb_subset_plan_create_or_fail (hb_face_t *face,
plan->reverse_glyph_map,
&plan->_num_output_glyphs);
// Now that we have old to new gid map update the unicode to new gid list.
for (unsigned i = 0; i < plan->unicode_to_new_gid_list->length; i++)
{
plan->unicode_to_new_gid_list->arrayZ[i].second =
plan->glyph_map->get(plan->unicode_to_new_gid_list->arrayZ[i].second);
}
if (unlikely (plan->in_error ())) {
hb_subset_plan_destroy (plan);
return nullptr;
@ -558,6 +583,11 @@ hb_subset_plan_destroy (hb_subset_plan_t *plan)
if (!hb_object_destroy (plan)) return;
hb_set_destroy (plan->unicodes);
if (plan->unicode_to_new_gid_list)
{
plan->unicode_to_new_gid_list->fini ();
hb_free (plan->unicode_to_new_gid_list);
}
hb_set_destroy (plan->name_ids);
hb_set_destroy (plan->name_languages);
hb_set_destroy (plan->layout_features);

View File

@ -44,6 +44,7 @@ struct hb_subset_plan_t
// For each cp that we'd like to retain maps to the corresponding gid.
hb_set_t *unicodes;
hb_vector_t<hb_pair_t<hb_codepoint_t, hb_codepoint_t>>* unicode_to_new_gid_list;
// name_ids we would like to retain
hb_set_t *name_ids;