Path: blob/master/thirdparty/harfbuzz/src/OT/glyf/glyf.hh
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#ifndef OT_GLYF_GLYF_HH
#define OT_GLYF_GLYF_HH
#include "../../hb-open-type.hh"
#include "../../hb-ot-head-table.hh"
#include "../../hb-ot-hmtx-table.hh"
#include "../../hb-ot-var-gvar-table.hh"
#include "../../hb-draw.hh"
#include "../../hb-paint.hh"
#include "glyf-helpers.hh"
#include "Glyph.hh"
#include "SubsetGlyph.hh"
#include "loca.hh"
#include "path-builder.hh"
namespace OT {
/*
* glyf -- TrueType Glyph Data
* https://docs.microsoft.com/en-us/typography/opentype/spec/glyf
*/
#define HB_OT_TAG_glyf HB_TAG('g','l','y','f')
struct glyf
{
friend struct glyf_accelerator_t;
static constexpr hb_tag_t tableTag = HB_OT_TAG_glyf;
static bool has_valid_glyf_format(const hb_face_t* face)
{
const OT::head &head = *face->table.head;
return head.indexToLocFormat <= 1 && head.glyphDataFormat <= 1;
}
bool sanitize (hb_sanitize_context_t *c HB_UNUSED) const
{
TRACE_SANITIZE (this);
/* Runtime checks as eager sanitizing each glyph is costy */
return_trace (true);
}
/* requires source of SubsetGlyph complains the identifier isn't declared */
template <typename Iterator>
bool serialize (hb_serialize_context_t *c,
Iterator it,
bool use_short_loca,
const hb_subset_plan_t *plan)
{
TRACE_SERIALIZE (this);
unsigned init_len = c->length ();
for (auto &_ : it)
if (unlikely (!_.serialize (c, use_short_loca, plan)))
return false;
/* As a special case when all glyph in the font are empty, add a zero byte
* to the table, so that OTS doesn’t reject it, and to make the table work
* on Windows as well.
* See https://github.com/khaledhosny/ots/issues/52 */
if (init_len == c->length ())
{
HBUINT8 empty_byte;
empty_byte = 0;
c->copy (empty_byte);
}
return_trace (true);
}
/* Byte region(s) per glyph to output
unpadded, hints removed if so requested
If we fail to process a glyph we produce an empty (0-length) glyph */
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
if (!has_valid_glyf_format (c->plan->source)) {
// glyf format is unknown don't attempt to subset it.
DEBUG_MSG (SUBSET, nullptr,
"unkown glyf format, dropping from subset.");
return_trace (false);
}
hb_font_t *font = nullptr;
if (c->plan->normalized_coords)
{
font = _create_font_for_instancing (c->plan);
if (unlikely (!font))
return_trace (false);
}
hb_vector_t<unsigned> padded_offsets;
if (unlikely (!padded_offsets.alloc_exact (c->plan->new_to_old_gid_list.length)))
return_trace (false);
hb_vector_t<glyf_impl::SubsetGlyph> glyphs;
if (!_populate_subset_glyphs (c->plan, font, glyphs))
{
hb_font_destroy (font);
return_trace (false);
}
if (font)
hb_font_destroy (font);
unsigned max_offset = 0;
for (auto &g : glyphs)
{
unsigned size = g.padded_size ();
padded_offsets.push (size);
max_offset += size;
}
bool use_short_loca = false;
if (likely (!c->plan->force_long_loca))
use_short_loca = max_offset < 0x1FFFF;
if (!use_short_loca)
{
padded_offsets.resize (0);
for (auto &g : glyphs)
padded_offsets.push (g.length ());
}
auto *glyf_prime = c->serializer->start_embed <glyf> ();
bool result = glyf_prime->serialize (c->serializer, hb_iter (glyphs), use_short_loca, c->plan);
if (c->plan->normalized_coords && !c->plan->pinned_at_default)
_free_compiled_subset_glyphs (glyphs);
if (unlikely (!c->serializer->check_success (glyf_impl::_add_loca_and_head (c,
padded_offsets.iter (),
use_short_loca))))
return_trace (false);
return result;
}
bool
_populate_subset_glyphs (const hb_subset_plan_t *plan,
hb_font_t *font,
hb_vector_t<glyf_impl::SubsetGlyph>& glyphs /* OUT */) const;
hb_font_t *
_create_font_for_instancing (const hb_subset_plan_t *plan) const;
void _free_compiled_subset_glyphs (hb_vector_t<glyf_impl::SubsetGlyph> &glyphs) const
{
for (auto &g : glyphs)
g.free_compiled_bytes ();
}
protected:
UnsizedArrayOf<HBUINT8>
dataZ; /* Glyphs data. */
public:
DEFINE_SIZE_MIN (0); /* In reality, this is UNBOUNDED() type; but since we always
* check the size externally, allow Null() object of it by
* defining it _MIN instead. */
};
struct glyf_accelerator_t
{
glyf_accelerator_t (hb_face_t *face)
{
short_offset = false;
num_glyphs = 0;
loca_table = nullptr;
glyf_table = nullptr;
#ifndef HB_NO_VAR
gvar = nullptr;
#ifndef HB_NO_BEYOND_64K
GVAR = nullptr;
#endif
#endif
hmtx = nullptr;
#ifndef HB_NO_VERTICAL
vmtx = nullptr;
#endif
const OT::head &head = *face->table.head;
if (!glyf::has_valid_glyf_format (face))
/* Unknown format. Leave num_glyphs=0, that takes care of disabling us. */
return;
short_offset = 0 == head.indexToLocFormat;
loca_table = face->table.loca.get_blob (); // Needs no destruct!
glyf_table = hb_sanitize_context_t ().reference_table<glyf> (face);
#ifndef HB_NO_VAR
gvar = face->table.gvar;
#ifndef HB_NO_BEYOND_64K
GVAR = face->table.GVAR;
#endif
#endif
hmtx = face->table.hmtx;
#ifndef HB_NO_VERTICAL
vmtx = face->table.vmtx;
#endif
num_glyphs = hb_max (1u, loca_table.get_length () / (short_offset ? 2 : 4)) - 1;
num_glyphs = hb_min (num_glyphs, face->get_num_glyphs ());
}
~glyf_accelerator_t ()
{
auto *scratch = cached_scratch.get_relaxed ();
if (scratch)
{
scratch->~hb_glyf_scratch_t ();
hb_free (scratch);
}
glyf_table.destroy ();
}
bool has_data () const { return num_glyphs; }
protected:
template<typename T>
bool get_points (hb_font_t *font, hb_codepoint_t gid, T consumer,
hb_array_t<const int> coords,
hb_glyf_scratch_t &scratch,
hb_scalar_cache_t *gvar_cache = nullptr) const
{
if (gid >= num_glyphs) return false;
auto &all_points = scratch.all_points;
all_points.resize (0);
bool phantom_only = !consumer.is_consuming_contour_points ();
if (unlikely (!glyph_for_gid (gid).get_points (font, *this, all_points, scratch, nullptr, nullptr, nullptr, true, true, phantom_only, coords, gvar_cache)))
return false;
unsigned count = all_points.length;
assert (count >= glyf_impl::PHANTOM_COUNT);
count -= glyf_impl::PHANTOM_COUNT;
if (consumer.is_consuming_contour_points ())
{
auto *points = all_points.arrayZ;
if (false)
{
/* Our path-builder was designed to work with this simple loop.
* But FreeType and CoreText do it differently, so we match those
* with the other, more complicated, code branch below. */
for (unsigned i = 0; i < count; i++)
{
consumer.consume_point (points[i]);
if (points[i].is_end_point)
consumer.contour_end ();
}
}
else
{
for (unsigned i = 0; i < count; i++)
{
// Start of a contour.
if (points[i].flag & glyf_impl::SimpleGlyph::FLAG_ON_CURVE)
{
// First point is on-curve. Draw the contour.
for (; i < count; i++)
{
consumer.consume_point (points[i]);
if (points[i].is_end_point)
{
consumer.contour_end ();
break;
}
}
}
else
{
unsigned start = i;
// Find end of the contour.
for (; i < count; i++)
if (points[i].is_end_point)
break;
unsigned end = i;
// Enough to start from the end. Our path-builder takes care of the rest.
if (likely (end < count)) // Can only fail in case of alloc failure *maybe*.
consumer.consume_point (points[end]);
for (i = start; i < end; i++)
consumer.consume_point (points[i]);
consumer.contour_end ();
}
}
}
consumer.points_end ();
}
/* Where to write phantoms, nullptr if not requested */
contour_point_t *phantoms = consumer.get_phantoms_sink ();
if (phantoms)
for (unsigned i = 0; i < glyf_impl::PHANTOM_COUNT; ++i)
phantoms[i] = all_points.arrayZ[count + i];
return true;
}
public:
#ifndef HB_NO_VAR
struct points_aggregator_t
{
hb_font_t *font;
hb_glyph_extents_t *extents;
contour_point_t *phantoms;
bool scaled;
struct contour_bounds_t
{
contour_bounds_t () { min_x = min_y = FLT_MAX; max_x = max_y = -FLT_MAX; }
void add (const contour_point_t &p)
{
min_x = hb_min (min_x, p.x);
min_y = hb_min (min_y, p.y);
max_x = hb_max (max_x, p.x);
max_y = hb_max (max_y, p.y);
}
bool empty () const { return (min_x >= max_x) || (min_y >= max_y); }
void get_extents (hb_font_t *font, hb_glyph_extents_t *extents, bool scaled)
{
if (unlikely (empty ()))
{
extents->width = 0;
extents->x_bearing = 0;
extents->height = 0;
extents->y_bearing = 0;
return;
}
{
extents->x_bearing = roundf (min_x);
extents->width = roundf (max_x - extents->x_bearing);
extents->y_bearing = roundf (max_y);
extents->height = roundf (min_y - extents->y_bearing);
if (scaled)
font->scale_glyph_extents (extents);
}
}
protected:
float min_x, min_y, max_x, max_y;
} bounds;
points_aggregator_t (hb_font_t *font_, hb_glyph_extents_t *extents_, contour_point_t *phantoms_, bool scaled_)
{
font = font_;
extents = extents_;
phantoms = phantoms_;
scaled = scaled_;
if (extents) bounds = contour_bounds_t ();
}
HB_ALWAYS_INLINE
void consume_point (const contour_point_t &point) { bounds.add (point); }
void contour_end () {}
void points_end () { bounds.get_extents (font, extents, scaled); }
bool is_consuming_contour_points () { return extents; }
contour_point_t *get_phantoms_sink () { return phantoms; }
};
#ifndef HB_NO_VAR
unsigned
get_advance_with_var_unscaled (hb_codepoint_t gid,
hb_font_t *font,
bool is_vertical,
hb_glyf_scratch_t &scratch,
hb_scalar_cache_t *gvar_cache = nullptr) const
{
if (unlikely (gid >= num_glyphs)) return 0;
bool success = false;
contour_point_t phantoms[glyf_impl::PHANTOM_COUNT];
success = get_points (font, gid, points_aggregator_t (font, nullptr, phantoms, false),
hb_array (font->coords,
font->has_nonzero_coords ? font->num_coords : 0),
scratch, gvar_cache);
if (unlikely (!success))
{
unsigned upem = font->face->get_upem ();
return is_vertical ? upem : upem / 2;
}
float result = is_vertical
? phantoms[glyf_impl::PHANTOM_TOP].y - phantoms[glyf_impl::PHANTOM_BOTTOM].y
: phantoms[glyf_impl::PHANTOM_RIGHT].x - phantoms[glyf_impl::PHANTOM_LEFT].x;
return hb_clamp (roundf (result), 0.f, (float) UINT_MAX / 2);
}
float
get_v_origin_with_var_unscaled (hb_codepoint_t gid,
hb_font_t *font,
hb_glyf_scratch_t &scratch,
hb_scalar_cache_t *gvar_cache = nullptr) const
{
if (unlikely (gid >= num_glyphs)) return 0;
bool success = false;
contour_point_t phantoms[glyf_impl::PHANTOM_COUNT];
success = get_points (font, gid, points_aggregator_t (font, nullptr, phantoms, false),
hb_array (font->coords,
font->has_nonzero_coords ? font->num_coords : 0),
scratch, gvar_cache);
if (unlikely (!success))
{
return font->face->get_upem ();
}
return phantoms[glyf_impl::PHANTOM_TOP].y;
}
#endif
#endif
public:
bool get_extents (hb_font_t *font,
hb_codepoint_t gid,
hb_glyph_extents_t *extents) const
{ return get_extents_at (font, gid, extents, hb_array (font->coords,
font->has_nonzero_coords ? font->num_coords : 0)); }
bool get_extents_at (hb_font_t *font,
hb_codepoint_t gid,
hb_glyph_extents_t *extents,
hb_array_t<const int> coords) const
{
if (unlikely (gid >= num_glyphs)) return false;
#ifndef HB_NO_VAR
if (coords)
{
hb_glyf_scratch_t *scratch = acquire_scratch ();
if (unlikely (!scratch))
return false;
bool ret = get_points (font,
gid,
points_aggregator_t (font, extents, nullptr, true),
coords,
*scratch);
release_scratch (scratch);
return ret;
}
#endif
return glyph_for_gid (gid).get_extents_without_var_scaled (font, *this, extents);
}
const glyf_impl::Glyph
glyph_for_gid (hb_codepoint_t gid, bool needs_padding_removal = false) const
{
if (unlikely (gid >= num_glyphs)) return glyf_impl::Glyph ();
unsigned int start_offset, end_offset;
if (short_offset)
{
const HBUINT16 *offsets = (const HBUINT16 *) loca_table->dataZ.arrayZ;
start_offset = 2 * offsets[gid];
end_offset = 2 * offsets[gid + 1];
}
else
{
const HBUINT32 *offsets = (const HBUINT32 *) loca_table->dataZ.arrayZ;
start_offset = offsets[gid];
end_offset = offsets[gid + 1];
}
if (unlikely (start_offset > end_offset || end_offset > glyf_table.get_length ()))
return glyf_impl::Glyph ();
glyf_impl::Glyph glyph (hb_bytes_t ((const char *) this->glyf_table + start_offset,
end_offset - start_offset), gid);
return needs_padding_removal ? glyf_impl::Glyph (glyph.trim_padding (), gid) : glyph;
}
bool
get_path (hb_font_t *font, hb_codepoint_t gid, hb_draw_session_t &draw_session, hb_scalar_cache_t *gvar_cache = nullptr) const
{
if (!has_data ()) return false;
hb_glyf_scratch_t *scratch = acquire_scratch ();
if (unlikely (!scratch))
return true;
bool ret = get_points (font, gid, glyf_impl::path_builder_t (font, draw_session),
hb_array (font->coords,
font->has_nonzero_coords ? font->num_coords : 0),
*scratch,
gvar_cache);
release_scratch (scratch);
return ret;
}
bool
get_path_at (hb_font_t *font, hb_codepoint_t gid, hb_draw_session_t &draw_session,
hb_array_t<const int> coords,
hb_glyf_scratch_t &scratch,
hb_scalar_cache_t *gvar_cache = nullptr) const
{
if (!has_data ()) return false;
return get_points (font, gid, glyf_impl::path_builder_t (font, draw_session),
coords,
scratch,
gvar_cache);
}
hb_glyf_scratch_t *acquire_scratch () const
{
hb_glyf_scratch_t *scratch = cached_scratch.get_acquire ();
if (!scratch || unlikely (!cached_scratch.cmpexch (scratch, nullptr)))
{
scratch = (hb_glyf_scratch_t *) hb_calloc (1, sizeof (hb_glyf_scratch_t));
if (unlikely (!scratch))
return nullptr;
}
return scratch;
}
void release_scratch (hb_glyf_scratch_t *scratch) const
{
if (!cached_scratch.cmpexch (nullptr, scratch))
{
scratch->~hb_glyf_scratch_t ();
hb_free (scratch);
}
}
#ifndef HB_NO_VAR
const gvar_accelerator_t *gvar;
#ifndef HB_NO_BEYOND_64K
const GVAR_accelerator_t *GVAR;
#endif
#endif
const hmtx_accelerator_t *hmtx;
#ifndef HB_NO_VERTICAL
const vmtx_accelerator_t *vmtx;
#endif
private:
bool short_offset;
unsigned int num_glyphs;
hb_blob_ptr_t<loca> loca_table;
hb_blob_ptr_t<glyf> glyf_table;
mutable hb_atomic_t<hb_glyf_scratch_t *> cached_scratch;
};
inline bool
glyf::_populate_subset_glyphs (const hb_subset_plan_t *plan,
hb_font_t *font,
hb_vector_t<glyf_impl::SubsetGlyph>& glyphs /* OUT */) const
{
OT::glyf_accelerator_t glyf (plan->source);
if (!glyphs.alloc_exact (plan->new_to_old_gid_list.length)) return false;
for (const auto &pair : plan->new_to_old_gid_list)
{
hb_codepoint_t new_gid = pair.first;
hb_codepoint_t old_gid = pair.second;
glyf_impl::SubsetGlyph *p = glyphs.push ();
glyf_impl::SubsetGlyph& subset_glyph = *p;
subset_glyph.old_gid = old_gid;
if (unlikely (old_gid == 0 && new_gid == 0 &&
!(plan->flags & HB_SUBSET_FLAGS_NOTDEF_OUTLINE)) &&
!plan->normalized_coords)
subset_glyph.source_glyph = glyf_impl::Glyph ();
else
{
/* If plan has an accelerator, the preprocessing step already trimmed glyphs.
* Don't trim them again! */
subset_glyph.source_glyph = glyf.glyph_for_gid (subset_glyph.old_gid, !plan->accelerator);
}
if (plan->flags & HB_SUBSET_FLAGS_NO_HINTING)
subset_glyph.drop_hints_bytes ();
else
subset_glyph.dest_start = subset_glyph.source_glyph.get_bytes ();
if (font)
{
if (unlikely (!subset_glyph.compile_bytes_with_deltas (plan, font, glyf)))
{
// when pinned at default, only bounds are updated, thus no need to free
if (!plan->pinned_at_default)
_free_compiled_subset_glyphs (glyphs);
return false;
}
}
}
return true;
}
inline hb_font_t *
glyf::_create_font_for_instancing (const hb_subset_plan_t *plan) const
{
hb_font_t *font = hb_font_create (plan->source);
if (unlikely (font == hb_font_get_empty ())) return nullptr;
hb_vector_t<hb_variation_t> vars;
if (unlikely (!vars.alloc (plan->user_axes_location.get_population (), true)))
{
hb_font_destroy (font);
return nullptr;
}
for (auto _ : plan->user_axes_location)
{
hb_variation_t var;
var.tag = _.first;
var.value = _.second.middle;
vars.push (var);
}
#ifndef HB_NO_VAR
hb_font_set_variations (font, vars.arrayZ, plan->user_axes_location.get_population ());
#endif
return font;
}
} /* namespace OT */
#endif /* OT_GLYF_GLYF_HH */