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#ifndef OT_LAYOUT_GPOS_CURSIVEPOSFORMAT1_HH
#define OT_LAYOUT_GPOS_CURSIVEPOSFORMAT1_HH
#include "Anchor.hh"
namespace OT {
namespace Layout {
namespace GPOS_impl {
struct EntryExitRecord
{
friend struct CursivePosFormat1;
bool sanitize (hb_sanitize_context_t *c, const struct CursivePosFormat1 *base) const
{
TRACE_SANITIZE (this);
return_trace (entryAnchor.sanitize (c, base) && exitAnchor.sanitize (c, base));
}
void collect_variation_indices (hb_collect_variation_indices_context_t *c,
const struct CursivePosFormat1 *src_base) const
{
(src_base+entryAnchor).collect_variation_indices (c);
(src_base+exitAnchor).collect_variation_indices (c);
}
bool subset (hb_subset_context_t *c,
const struct CursivePosFormat1 *src_base) const
{
TRACE_SERIALIZE (this);
auto *out = c->serializer->embed (this);
if (unlikely (!out)) return_trace (false);
bool ret = false;
ret |= out->entryAnchor.serialize_subset (c, entryAnchor, src_base);
ret |= out->exitAnchor.serialize_subset (c, exitAnchor, src_base);
return_trace (ret);
}
protected:
Offset16To<Anchor, struct CursivePosFormat1>
entryAnchor; /* Offset to EntryAnchor table--from
* beginning of CursivePos
* subtable--may be NULL */
Offset16To<Anchor, struct CursivePosFormat1>
exitAnchor; /* Offset to ExitAnchor table--from
* beginning of CursivePos
* subtable--may be NULL */
public:
DEFINE_SIZE_STATIC (4);
};
static void
reverse_cursive_minor_offset (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction, unsigned int new_parent) {
int chain = pos[i].attach_chain(), type = pos[i].attach_type();
if (likely (!chain || 0 == (type & ATTACH_TYPE_CURSIVE)))
return;
pos[i].attach_chain() = 0;
unsigned int j = (int) i + chain;
/* Stop if we see new parent in the chain. */
if (j == new_parent)
return;
reverse_cursive_minor_offset (pos, j, direction, new_parent);
if (HB_DIRECTION_IS_HORIZONTAL (direction))
pos[j].y_offset = -pos[i].y_offset;
else
pos[j].x_offset = -pos[i].x_offset;
pos[j].attach_chain() = -chain;
pos[j].attach_type() = type;
}
struct CursivePosFormat1
{
protected:
HBUINT16 format; /* Format identifier--format = 1 */
Offset16To<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of subtable */
Array16Of<EntryExitRecord>
entryExitRecord; /* Array of EntryExit records--in
* Coverage Index order */
public:
DEFINE_SIZE_ARRAY (6, entryExitRecord);
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!coverage.sanitize (c, this)))
return_trace (false);
if (c->lazy_some_gpos)
return_trace (entryExitRecord.sanitize_shallow (c));
else
return_trace (entryExitRecord.sanitize (c, this));
}
bool intersects (const hb_set_t *glyphs) const
{ return (this+coverage).intersects (glyphs); }
void closure_lookups (hb_closure_lookups_context_t *c) const {}
void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
{
+ hb_zip (this+coverage, entryExitRecord)
| hb_filter (c->glyph_set, hb_first)
| hb_map (hb_second)
| hb_apply ([&] (const EntryExitRecord& record) { record.collect_variation_indices (c, this); })
;
}
void collect_glyphs (hb_collect_glyphs_context_t *c) const
{ if (unlikely (!(this+coverage).collect_coverage (c->input))) return; }
const Coverage &get_coverage () const { return this+coverage; }
bool apply (hb_ot_apply_context_t *c) const
{
TRACE_APPLY (this);
hb_buffer_t *buffer = c->buffer;
const EntryExitRecord &this_record = entryExitRecord[(this+coverage).get_coverage (buffer->cur().codepoint)];
if (!this_record.entryAnchor ||
unlikely (!this_record.entryAnchor.sanitize (&c->sanitizer, this))) return_trace (false);
hb_barrier ();
hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input;
skippy_iter.reset_fast (buffer->idx);
unsigned unsafe_from;
if (unlikely (!skippy_iter.prev (&unsafe_from)))
{
buffer->unsafe_to_concat_from_outbuffer (unsafe_from, buffer->idx + 1);
return_trace (false);
}
const EntryExitRecord &prev_record = entryExitRecord[(this+coverage).get_coverage (buffer->info[skippy_iter.idx].codepoint)];
if (!prev_record.exitAnchor ||
unlikely (!prev_record.exitAnchor.sanitize (&c->sanitizer, this)))
{
buffer->unsafe_to_concat_from_outbuffer (skippy_iter.idx, buffer->idx + 1);
return_trace (false);
}
hb_barrier ();
unsigned int i = skippy_iter.idx;
unsigned int j = buffer->idx;
if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
{
c->buffer->message (c->font,
"cursive attaching glyph at %u to glyph at %u",
i, j);
}
buffer->unsafe_to_break (i, j + 1);
float entry_x, entry_y, exit_x, exit_y;
(this+prev_record.exitAnchor).get_anchor (c, buffer->info[i].codepoint, &exit_x, &exit_y);
(this+this_record.entryAnchor).get_anchor (c, buffer->info[j].codepoint, &entry_x, &entry_y);
hb_glyph_position_t *pos = buffer->pos;
hb_position_t d;
/* Main-direction adjustment */
switch (c->direction) {
case HB_DIRECTION_LTR:
pos[i].x_advance = roundf (exit_x) + pos[i].x_offset;
d = roundf (entry_x) + pos[j].x_offset;
pos[j].x_advance -= d;
pos[j].x_offset -= d;
break;
case HB_DIRECTION_RTL:
d = roundf (exit_x) + pos[i].x_offset;
pos[i].x_advance -= d;
pos[i].x_offset -= d;
pos[j].x_advance = roundf (entry_x) + pos[j].x_offset;
break;
case HB_DIRECTION_TTB:
pos[i].y_advance = roundf (exit_y) + pos[i].y_offset;
d = roundf (entry_y) + pos[j].y_offset;
pos[j].y_advance -= d;
pos[j].y_offset -= d;
break;
case HB_DIRECTION_BTT:
d = roundf (exit_y) + pos[i].y_offset;
pos[i].y_advance -= d;
pos[i].y_offset -= d;
pos[j].y_advance = roundf (entry_y);
break;
case HB_DIRECTION_INVALID:
default:
break;
}
/* Cross-direction adjustment */
/* We attach child to parent (think graph theory and rooted trees whereas
* the root stays on baseline and each node aligns itself against its
* parent.
*
* Optimize things for the case of RightToLeft, as that's most common in
* Arabic. */
unsigned int child = i;
unsigned int parent = j;
hb_position_t x_offset = roundf (entry_x - exit_x);
hb_position_t y_offset = roundf (entry_y - exit_y);
if (!(c->lookup_props & LookupFlag::RightToLeft))
{
unsigned int k = child;
child = parent;
parent = k;
x_offset = -x_offset;
y_offset = -y_offset;
}
/* If child was already connected to someone else, walk through its old
* chain and reverse the link direction, such that the whole tree of its
* previous connection now attaches to new parent. Watch out for case
* where new parent is on the path from old chain...
*/
reverse_cursive_minor_offset (pos, child, c->direction, parent);
pos[child].attach_type() = ATTACH_TYPE_CURSIVE;
pos[child].attach_chain() = (int) parent - (int) child;
buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_ATTACHMENT;
if (likely (HB_DIRECTION_IS_HORIZONTAL (c->direction)))
pos[child].y_offset = y_offset;
else
pos[child].x_offset = x_offset;
/* If parent was attached to child, separate them.
*/
if (unlikely (pos[parent].attach_chain() == -pos[child].attach_chain()))
{
pos[parent].attach_chain() = 0;
if (likely (HB_DIRECTION_IS_HORIZONTAL (c->direction)))
pos[parent].y_offset = 0;
else
pos[parent].x_offset = 0;
}
if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
{
c->buffer->message (c->font,
"cursive attached glyph at %u to glyph at %u",
i, j);
}
buffer->idx++;
return_trace (true);
}
template <typename Iterator,
hb_requires (hb_is_iterator (Iterator))>
void serialize (hb_subset_context_t *c,
Iterator it,
const struct CursivePosFormat1 *src_base)
{
if (unlikely (!c->serializer->extend_min ((*this)))) return;
this->format = 1;
this->entryExitRecord.len = it.len ();
for (const EntryExitRecord& entry_record : + it
| hb_map (hb_second))
entry_record.subset (c, src_base);
auto glyphs =
+ it
| hb_map_retains_sorting (hb_first)
;
coverage.serialize_serialize (c->serializer, glyphs);
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
const hb_map_t &glyph_map = *c->plan->glyph_map;
auto *out = c->serializer->start_embed (*this);
auto it =
+ hb_zip (this+coverage, entryExitRecord)
| hb_filter (glyphset, hb_first)
| hb_map_retains_sorting ([&] (hb_pair_t<hb_codepoint_t, const EntryExitRecord&> p) -> hb_pair_t<hb_codepoint_t, const EntryExitRecord&>
{ return hb_pair (glyph_map[p.first], p.second);})
;
bool ret = bool (it);
out->serialize (c, it, this);
return_trace (ret);
}
};
}
}
}
#endif /* OT_LAYOUT_GPOS_CURSIVEPOSFORMAT1_HH */