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#ifndef OT_LAYOUT_GSUB_LIGATURE_HH
#define OT_LAYOUT_GSUB_LIGATURE_HH
#include "Common.hh"
namespace OT {
namespace Layout {
namespace GSUB_impl {
template <typename Types>
struct Ligature
{
public:
typename Types::HBGlyphID
ligGlyph; /* GlyphID of ligature to substitute */
HeadlessArray16Of<typename Types::HBGlyphID>
component; /* Array of component GlyphIDs--start
* with the second component--ordered
* in writing direction */
public:
DEFINE_SIZE_ARRAY (Types::size + 2, component);
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (ligGlyph.sanitize (c) && component.sanitize (c));
}
bool intersects (const hb_set_t *glyphs) const
{ return hb_all (component, glyphs); }
bool intersects_lig_glyph (const hb_set_t *glyphs) const
{ return glyphs->has(ligGlyph); }
void closure (hb_closure_context_t *c) const
{
if (!intersects (c->glyphs)) return;
c->output->add (ligGlyph);
}
void collect_glyphs (hb_collect_glyphs_context_t *c) const
{
c->input->add_array (component.arrayZ, component.get_length ());
c->output->add (ligGlyph);
}
bool would_apply (hb_would_apply_context_t *c) const
{
if (c->len != component.lenP1)
return false;
for (unsigned int i = 1; i < c->len; i++)
if (likely (c->glyphs[i] != component[i]))
return false;
return true;
}
bool apply (hb_ot_apply_context_t *c) const
{
TRACE_APPLY (this);
unsigned int count = component.lenP1;
if (unlikely (!count)) return_trace (false);
/* Special-case to make it in-place and not consider this
* as a "ligated" substitution. */
if (unlikely (count == 1))
{
if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
{
c->buffer->sync_so_far ();
c->buffer->message (c->font,
"replacing glyph at %u (ligature substitution)",
c->buffer->idx);
}
c->replace_glyph (ligGlyph);
if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
{
c->buffer->message (c->font,
"replaced glyph at %u (ligature substitution)",
c->buffer->idx - 1u);
}
return_trace (true);
}
unsigned int total_component_count = 0;
if (unlikely (count > HB_MAX_CONTEXT_LENGTH)) return false;
unsigned match_positions_stack[4];
unsigned *match_positions = match_positions_stack;
if (unlikely (count > ARRAY_LENGTH (match_positions_stack)))
{
match_positions = (unsigned *) hb_malloc (hb_max (count, 1u) * sizeof (unsigned));
if (unlikely (!match_positions))
return_trace (false);
}
unsigned int match_end = 0;
if (likely (!match_input (c, count,
&component[1],
match_glyph,
nullptr,
&match_end,
match_positions,
&total_component_count)))
{
c->buffer->unsafe_to_concat (c->buffer->idx, match_end);
if (match_positions != match_positions_stack)
hb_free (match_positions);
return_trace (false);
}
unsigned pos = 0;
if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
{
unsigned delta = c->buffer->sync_so_far ();
pos = c->buffer->idx;
char buf[HB_MAX_CONTEXT_LENGTH * 16] = {0};
char *p = buf;
match_end += delta;
for (unsigned i = 0; i < count; i++)
{
match_positions[i] += delta;
if (i)
*p++ = ',';
snprintf (p, sizeof(buf) - (p - buf), "%u", match_positions[i]);
p += strlen(p);
}
c->buffer->message (c->font,
"ligating glyphs at %s",
buf);
}
ligate_input (c,
count,
match_positions,
match_end,
ligGlyph,
total_component_count);
if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
{
c->buffer->sync_so_far ();
c->buffer->message (c->font,
"ligated glyph at %u",
pos);
}
if (match_positions != match_positions_stack)
hb_free (match_positions);
return_trace (true);
}
template <typename Iterator,
hb_requires (hb_is_source_of (Iterator, hb_codepoint_t))>
bool serialize (hb_serialize_context_t *c,
hb_codepoint_t ligature,
Iterator components /* Starting from second */)
{
TRACE_SERIALIZE (this);
if (unlikely (!c->extend_min (this))) return_trace (false);
ligGlyph = ligature;
if (unlikely (!component.serialize (c, components))) return_trace (false);
return_trace (true);
}
bool subset (hb_subset_context_t *c, unsigned coverage_idx) const
{
TRACE_SUBSET (this);
const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
const hb_map_t &glyph_map = *c->plan->glyph_map;
if (!intersects (&glyphset) || !glyphset.has (ligGlyph)) return_trace (false);
// Ensure Coverage table is always packed after this.
c->serializer->add_virtual_link (coverage_idx);
auto it =
+ hb_iter (component)
| hb_map (glyph_map)
;
auto *out = c->serializer->start_embed (*this);
return_trace (out->serialize (c->serializer,
glyph_map[ligGlyph],
it)); }
};
}
}
}
#endif /* OT_LAYOUT_GSUB_LIGATURE_HH */