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/*
* Copyright © 2015 Google, Inc.
* Copyright © 2019 Adobe Inc.
* Copyright © 2019 Ebrahim Byagowi
*
* 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): Behdad Esfahbod, Garret Rieger, Roderick Sheeter
* Adobe Author(s): Michiharu Ariza
*/
#ifndef HB_OT_GLYF_TABLE_HH
#define HB_OT_GLYF_TABLE_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 <float.h>
namespace OT {
/*
* loca -- Index to Location
* https://docs.microsoft.com/en-us/typography/opentype/spec/loca
*/
#define HB_OT_TAG_loca HB_TAG('l','o','c','a')
struct loca
{
friend struct glyf;
static constexpr hb_tag_t tableTag = HB_OT_TAG_loca;
bool sanitize (hb_sanitize_context_t *c HB_UNUSED) const
{
TRACE_SANITIZE (this);
return_trace (true);
}
protected:
UnsizedArrayOf<HBUINT8>
dataZ; /* Location 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. */
};
/*
* 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
{
static constexpr hb_tag_t tableTag = HB_OT_TAG_glyf;
bool sanitize (hb_sanitize_context_t *c HB_UNUSED) const
{
TRACE_SANITIZE (this);
/* We don't check for anything specific here. The users of the
* struct do all the hard work... */
return_trace (true);
}
template<typename Iterator,
hb_requires (hb_is_source_of (Iterator, unsigned int))>
static bool
_add_loca_and_head (hb_subset_plan_t * plan, Iterator padded_offsets)
{
unsigned max_offset = + padded_offsets | hb_reduce(hb_add, 0);
unsigned num_offsets = padded_offsets.len () + 1;
bool use_short_loca = max_offset < 0x1FFFF;
unsigned entry_size = use_short_loca ? 2 : 4;
char *loca_prime_data = (char *) calloc (entry_size, num_offsets);
if (unlikely (!loca_prime_data)) return false;
DEBUG_MSG (SUBSET, nullptr, "loca entry_size %d num_offsets %d "
"max_offset %d size %d",
entry_size, num_offsets, max_offset, entry_size * num_offsets);
if (use_short_loca)
_write_loca (padded_offsets, 1, hb_array ((HBUINT16*) loca_prime_data, num_offsets));
else
_write_loca (padded_offsets, 0, hb_array ((HBUINT32*) loca_prime_data, num_offsets));
hb_blob_t * loca_blob = hb_blob_create (loca_prime_data,
entry_size * num_offsets,
HB_MEMORY_MODE_WRITABLE,
loca_prime_data,
free);
bool result = plan->add_table (HB_OT_TAG_loca, loca_blob)
&& _add_head_and_set_loca_version (plan, use_short_loca);
hb_blob_destroy (loca_blob);
return result;
}
template<typename IteratorIn, typename IteratorOut,
hb_requires (hb_is_source_of (IteratorIn, unsigned int)),
hb_requires (hb_is_sink_of (IteratorOut, unsigned))>
static void
_write_loca (IteratorIn it, unsigned right_shift, IteratorOut dest)
{
unsigned int offset = 0;
dest << 0;
+ it
| hb_map ([=, &offset] (unsigned int padded_size)
{
offset += padded_size;
DEBUG_MSG (SUBSET, nullptr, "loca entry offset %d", offset);
return offset >> right_shift;
})
| hb_sink (dest)
;
}
// requires source of SubsetGlyph complains the identifier isn't declared
template <typename Iterator>
bool serialize (hb_serialize_context_t *c,
Iterator it,
const hb_subset_plan_t *plan)
{
TRACE_SERIALIZE (this);
for (const auto &_ : it) _.serialize (c, plan);
return_trace (true);
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
glyf *glyf_prime = c->serializer->start_embed <glyf> ();
if (unlikely (!c->serializer->check_success (glyf_prime))) return_trace (false);
// 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
hb_vector_t<SubsetGlyph> glyphs;
_populate_subset_glyphs (c->plan, &glyphs);
glyf_prime->serialize (c->serializer, hb_iter (glyphs), c->plan);
auto padded_offsets =
+ hb_iter (glyphs)
| hb_map (&SubsetGlyph::padded_size)
;
if (c->serializer->in_error ()) return_trace (false);
return_trace (c->serializer->check_success (_add_loca_and_head (c->plan,
padded_offsets)));
}
template <typename SubsetGlyph>
void
_populate_subset_glyphs (const hb_subset_plan_t * plan,
hb_vector_t<SubsetGlyph> * glyphs /* OUT */) const
{
OT::glyf::accelerator_t glyf;
glyf.init (plan->source);
+ hb_range (plan->num_output_glyphs ())
| hb_map ([&] (hb_codepoint_t new_gid)
{
SubsetGlyph subset_glyph = {0};
subset_glyph.new_gid = new_gid;
// should never fail: all old gids should be mapped
if (!plan->old_gid_for_new_gid (new_gid, &subset_glyph.old_gid))
return subset_glyph;
subset_glyph.source_glyph = glyf.bytes_for_glyph (subset_glyph.old_gid, true);
if (plan->drop_hints) subset_glyph.drop_hints (glyf);
else subset_glyph.dest_start = subset_glyph.source_glyph;
return subset_glyph;
})
| hb_sink (glyphs)
;
glyf.fini ();
}
static void
_fix_component_gids (const hb_subset_plan_t *plan,
hb_bytes_t glyph)
{
for (auto &item : OT::glyf::get_composite_iterator (glyph))
{
hb_codepoint_t new_gid;
if (plan->new_gid_for_old_gid (item.glyphIndex, &new_gid))
((OT::glyf::CompositeGlyphHeader *) &item)->glyphIndex = new_gid;
}
}
static void
_zero_instruction_length (hb_bytes_t glyph)
{
const GlyphHeader &glyph_header = *glyph.as<GlyphHeader> ();
if (!glyph_header.is_simple_glyph ()) return; // only for simple glyphs
unsigned int instruction_len_offset = GlyphHeader::SimpleHeader (glyph_header).instruction_len_offset ();
const HBUINT16 &instruction_len = StructAtOffset<HBUINT16> (&glyph, instruction_len_offset);
(HBUINT16 &) instruction_len = 0;
}
static bool _remove_composite_instruction_flag (hb_bytes_t glyph)
{
const GlyphHeader &glyph_header = *glyph.as<GlyphHeader> ();
if (!glyph_header.is_composite_glyph ()) return true; // only for composites
/* remove WE_HAVE_INSTRUCTIONS from flags in dest */
return
+ OT::glyf::get_composite_iterator (glyph)
| hb_reduce ([] (bool _, const OT::glyf::CompositeGlyphHeader &item)
{
OT::HBUINT16 *flags = const_cast<OT::HBUINT16 *> (&item.flags);
*flags = (uint16_t) *flags & ~OT::glyf::CompositeGlyphHeader::WE_HAVE_INSTRUCTIONS;
return true;
}, false)
;
}
static bool
_add_head_and_set_loca_version (hb_subset_plan_t *plan, bool use_short_loca)
{
hb_blob_t *head_blob = hb_sanitize_context_t ().reference_table<head> (plan->source);
hb_blob_t *head_prime_blob = hb_blob_copy_writable_or_fail (head_blob);
hb_blob_destroy (head_blob);
if (unlikely (!head_prime_blob))
return false;
head *head_prime = (head *) hb_blob_get_data_writable (head_prime_blob, nullptr);
head_prime->indexToLocFormat = use_short_loca ? 0 : 1;
bool success = plan->add_table (HB_OT_TAG_head, head_prime_blob);
hb_blob_destroy (head_prime_blob);
return success;
}
struct GlyphHeader
{
struct SimpleHeader
{
const GlyphHeader &header;
SimpleHeader (const GlyphHeader &header_) : header (header_) {}
unsigned int instruction_len_offset () const
{ return static_size + 2 * header.numberOfContours; }
unsigned int length (unsigned int instruction_len) const
{ return instruction_len_offset () + 2 + instruction_len; }
bool get_instruction_length (hb_bytes_t glyph, unsigned int *len) const
{
unsigned int instruction_length_offset = instruction_len_offset ();
if (unlikely (instruction_length_offset + 2 > glyph.length)) return false;
const HBUINT16 &instruction_len = StructAtOffset<HBUINT16> (&glyph, instruction_length_offset);
/* Out of bounds of the current glyph */
if (unlikely (length (instruction_len) > glyph.length)) return false;
*len = instruction_len;
return true;
}
};
struct CompositeHeader
{
const GlyphHeader &header;
CompositeHeader (const GlyphHeader &header_) : header (header_) {}
bool get_instruction_length (hb_bytes_t glyph, unsigned int *length)
{
unsigned int start = glyph.length;
unsigned int end = glyph.length;
const CompositeGlyphHeader *last = nullptr;
for (auto &item : get_composite_iterator (glyph))
last = &item;
if (unlikely (!last)) return false;
if ((uint16_t) last->flags & CompositeGlyphHeader::WE_HAVE_INSTRUCTIONS)
start = (char *) last - &glyph + last->get_size ();
if (unlikely (start > end)) return false;
*length = end - start;
return true;
}
};
enum glyph_type_t { EMPTY, SIMPLE, COMPOSITE };
glyph_type_t get_type () const
{
if (is_simple_glyph ()) return SIMPLE;
else if (is_composite_glyph ()) return COMPOSITE;
else return EMPTY;
}
bool get_instruction_length (hb_bytes_t glyph, unsigned int *length) const
{
switch (get_type ())
{
case COMPOSITE: return CompositeHeader (*this).get_instruction_length (glyph, length);
case SIMPLE: return SimpleHeader (*this).get_instruction_length (glyph, length);
default:
case EMPTY: *length = 0; return glyph.length == 0; /* only 0 byte glyphs are healthy when missing GlyphHeader */
}
}
bool has_data () const { return numberOfContours; }
bool is_simple_glyph () const { return numberOfContours > 0; }
bool is_composite_glyph () const { return numberOfContours < 0; }
HBINT16 numberOfContours;
/* If the number of contours is
* greater than or equal to zero,
* this is a simple glyph; if negative,
* this is a composite glyph. */
FWORD xMin; /* Minimum x for coordinate data. */
FWORD yMin; /* Minimum y for coordinate data. */
FWORD xMax; /* Maximum x for coordinate data. */
FWORD yMax; /* Maximum y for coordinate data. */
DEFINE_SIZE_STATIC (10);
};
struct CompositeGlyphHeader
{
enum composite_glyph_flag_t
{
ARG_1_AND_2_ARE_WORDS = 0x0001,
ARGS_ARE_XY_VALUES = 0x0002,
ROUND_XY_TO_GRID = 0x0004,
WE_HAVE_A_SCALE = 0x0008,
MORE_COMPONENTS = 0x0020,
WE_HAVE_AN_X_AND_Y_SCALE = 0x0040,
WE_HAVE_A_TWO_BY_TWO = 0x0080,
WE_HAVE_INSTRUCTIONS = 0x0100,
USE_MY_METRICS = 0x0200,
OVERLAP_COMPOUND = 0x0400,
SCALED_COMPONENT_OFFSET = 0x0800,
UNSCALED_COMPONENT_OFFSET = 0x1000
};
HBUINT16 flags;
HBGlyphID glyphIndex;
unsigned int get_size () const
{
unsigned int size = min_size;
// arg1 and 2 are int16
if (flags & ARG_1_AND_2_ARE_WORDS) size += 4;
// arg1 and 2 are int8
else size += 2;
// One x 16 bit (scale)
if (flags & WE_HAVE_A_SCALE) size += 2;
// Two x 16 bit (xscale, yscale)
else if (flags & WE_HAVE_AN_X_AND_Y_SCALE) size += 4;
// Four x 16 bit (xscale, scale01, scale10, yscale)
else if (flags & WE_HAVE_A_TWO_BY_TWO) size += 8;
return size;
}
bool is_anchored () const { return (flags & ARGS_ARE_XY_VALUES) == 0; }
void get_anchor_points (unsigned int &point1, unsigned int &point2) const
{
const HBUINT8 *p = &StructAfter<const HBUINT8> (glyphIndex);
if (flags & ARG_1_AND_2_ARE_WORDS)
{
point1 = ((const HBUINT16 *) p)[0];
point2 = ((const HBUINT16 *) p)[1];
}
else
{
point1 = p[0];
point2 = p[1];
}
}
void transform_points (contour_point_vector_t &points) const
{
float matrix[4];
contour_point_t trans;
if (get_transformation (matrix, trans))
{
if (scaled_offsets ())
{
points.translate (trans);
points.transform (matrix);
}
else
{
points.transform (matrix);
points.translate (trans);
}
}
}
protected:
bool scaled_offsets () const
{ return (flags & (SCALED_COMPONENT_OFFSET | UNSCALED_COMPONENT_OFFSET)) == SCALED_COMPONENT_OFFSET; }
bool get_transformation (float (&matrix)[4], contour_point_t &trans) const
{
matrix[0] = matrix[3] = 1.f;
matrix[1] = matrix[2] = 0.f;
int tx, ty;
const HBINT8 *p = &StructAfter<const HBINT8> (glyphIndex);
if (flags & ARG_1_AND_2_ARE_WORDS)
{
tx = *(const HBINT16 *) p;
p += HBINT16::static_size;
ty = *(const HBINT16 *) p;
p += HBINT16::static_size;
}
else
{
tx = *p++;
ty = *p++;
}
if (is_anchored ()) tx = ty = 0;
trans.init ((float) tx, (float) ty);
{
const F2DOT14 *points = (const F2DOT14 *) p;
if (flags & WE_HAVE_A_SCALE)
{
matrix[0] = matrix[3] = points[0].to_float ();
return true;
}
else if (flags & WE_HAVE_AN_X_AND_Y_SCALE)
{
matrix[0] = points[0].to_float ();
matrix[3] = points[1].to_float ();
return true;
}
else if (flags & WE_HAVE_A_TWO_BY_TWO)
{
matrix[0] = points[0].to_float ();
matrix[1] = points[1].to_float ();
matrix[2] = points[2].to_float ();
matrix[3] = points[3].to_float ();
return true;
}
}
return tx || ty;
}
public:
DEFINE_SIZE_MIN (4);
};
struct composite_iter_t : hb_iter_with_fallback_t<composite_iter_t, const CompositeGlyphHeader &>
{
typedef const CompositeGlyphHeader *__item_t__;
composite_iter_t (hb_bytes_t glyph_, __item_t__ current_) : glyph (glyph_), current (current_)
{ if (!in_range (current)) current = nullptr; }
composite_iter_t () : glyph (hb_bytes_t ()), current (nullptr) {}
const CompositeGlyphHeader &__item__ () const { return *current; }
bool __more__ () const { return current; }
void __next__ ()
{
if (!(current->flags & CompositeGlyphHeader::MORE_COMPONENTS)) { current = nullptr; return; }
const CompositeGlyphHeader *possible = &StructAfter<CompositeGlyphHeader,
CompositeGlyphHeader> (*current);
if (!in_range (possible)) { current = nullptr; return; }
current = possible;
}
bool operator != (const composite_iter_t& o) const
{ return glyph != o.glyph || current != o.current; }
bool in_range (const CompositeGlyphHeader *composite) const
{
return glyph.sub_array ((const char *) composite - (const char *) &glyph,
CompositeGlyphHeader::min_size).as<CompositeGlyphHeader> () != &Null (CompositeGlyphHeader);
}
private:
hb_bytes_t glyph;
__item_t__ current;
};
static composite_iter_t get_composite_iterator (hb_bytes_t glyph)
{
const GlyphHeader &glyph_header = *glyph.as<GlyphHeader> ();
if (!glyph_header.is_composite_glyph ()) return composite_iter_t ();
return composite_iter_t (glyph, &StructAfter<CompositeGlyphHeader, GlyphHeader> (glyph_header));
}
struct accelerator_t
{
void init (hb_face_t *face_)
{
short_offset = false;
num_glyphs = 0;
loca_table = nullptr;
glyf_table = nullptr;
face = face_;
const OT::head &head = *face->table.head;
if (head.indexToLocFormat > 1 || head.glyphDataFormat != 0)
/* Unknown format. Leave num_glyphs=0, that takes care of disabling us. */
return;
short_offset = 0 == head.indexToLocFormat;
loca_table = hb_sanitize_context_t ().reference_table<loca> (face);
glyf_table = hb_sanitize_context_t ().reference_table<glyf> (face);
num_glyphs = hb_max (1u, loca_table.get_length () / (short_offset ? 2 : 4)) - 1;
}
void fini ()
{
loca_table.destroy ();
glyf_table.destroy ();
}
enum simple_glyph_flag_t
{
FLAG_ON_CURVE = 0x01,
FLAG_X_SHORT = 0x02,
FLAG_Y_SHORT = 0x04,
FLAG_REPEAT = 0x08,
FLAG_X_SAME = 0x10,
FLAG_Y_SAME = 0x20,
FLAG_RESERVED1 = 0x40,
FLAG_RESERVED2 = 0x80
};
enum phantom_point_index_t
{
PHANTOM_LEFT = 0,
PHANTOM_RIGHT = 1,
PHANTOM_TOP = 2,
PHANTOM_BOTTOM = 3,
PHANTOM_COUNT = 4
};
protected:
struct x_setter_t
{
void set (contour_point_t &point, float v) const { point.x = v; }
bool is_short (uint8_t flag) const { return flag & FLAG_X_SHORT; }
bool is_same (uint8_t flag) const { return flag & FLAG_X_SAME; }
};
struct y_setter_t
{
void set (contour_point_t &point, float v) const { point.y = v; }
bool is_short (uint8_t flag) const { return flag & FLAG_Y_SHORT; }
bool is_same (uint8_t flag) const { return flag & FLAG_Y_SAME; }
};
template <typename T>
static bool read_points (const HBUINT8 *&p /* IN/OUT */,
contour_point_vector_t &points_ /* IN/OUT */,
const range_checker_t &checker)
{
T coord_setter;
float v = 0;
for (unsigned int i = 0; i < points_.length - PHANTOM_COUNT; i++)
{
uint8_t flag = points_[i].flag;
if (coord_setter.is_short (flag))
{
if (unlikely (!checker.in_range (p))) return false;
if (coord_setter.is_same (flag))
v += *p++;
else
v -= *p++;
}
else
{
if (!coord_setter.is_same (flag))
{
if (unlikely (!checker.in_range ((const HBUINT16 *)p))) return false;
v += *(const HBINT16 *) p;
p += HBINT16::static_size;
}
}
coord_setter.set (points_[i], v);
}
return true;
}
void init_phantom_points (hb_codepoint_t glyph, hb_array_t<contour_point_t> &phantoms /* IN/OUT */) const
{
const GlyphHeader &header = *bytes_for_glyph (glyph).as<GlyphHeader> ();
int h_delta = (int) header.xMin - face->table.hmtx->get_side_bearing (glyph);
int v_orig = (int) header.yMax + face->table.vmtx->get_side_bearing (glyph);
unsigned int h_adv = face->table.hmtx->get_advance (glyph);
unsigned int v_adv = face->table.vmtx->get_advance (glyph);
phantoms[PHANTOM_LEFT].x = h_delta;
phantoms[PHANTOM_RIGHT].x = h_adv + h_delta;
phantoms[PHANTOM_TOP].y = v_orig;
phantoms[PHANTOM_BOTTOM].y = v_orig - (int) v_adv;
}
/* for a simple glyph, return contour end points, flags, along with coordinate points
* for a composite glyph, return pseudo component points
* in both cases points trailed with four phantom points
*/
bool get_contour_points (hb_codepoint_t glyph,
contour_point_vector_t &points_ /* OUT */,
hb_vector_t<unsigned int> &end_points_ /* OUT */,
const bool phantom_only=false) const
{
unsigned int num_points = 0;
hb_bytes_t bytes = bytes_for_glyph (glyph);
const GlyphHeader &glyph_header = *bytes.as<GlyphHeader> ();
if (glyph_header.is_composite_glyph ())
{
/* add one pseudo point for each component in composite glyph */
num_points += hb_len (get_composite_iterator (bytes));
points_.resize (num_points + PHANTOM_COUNT);
for (unsigned int i = 0; i < points_.length; i++) points_[i].init ();
return true;
}
else if (glyph_header.is_simple_glyph ())
{
const HBUINT16 *end_pts = &StructAfter<HBUINT16, GlyphHeader> (glyph_header);
unsigned int start_offset, end_offset;
if (unlikely (!get_offsets (glyph, &start_offset, &end_offset))) return false;
range_checker_t checker (glyf_table, start_offset, end_offset);
num_points = 0;
int num_contours = glyph_header.numberOfContours;
if (unlikely (!checker.in_range (&end_pts[num_contours + 1]))) return false;
num_points = end_pts[glyph_header.numberOfContours - 1] + 1;
points_.resize (num_points + PHANTOM_COUNT);
for (unsigned int i = 0; i < points_.length; i++) points_[i].init ();
if (phantom_only) return true;
/* Read simple glyph points if !phantom_only */
end_points_.resize (num_contours);
for (int i = 0; i < num_contours; i++)
end_points_[i] = end_pts[i];
/* Skip instructions */
const HBUINT8 *p = &StructAtOffset<HBUINT8> (&end_pts[num_contours + 1],
end_pts[num_contours]);
/* Read flags */
for (unsigned int i = 0; i < num_points; i++)
{
if (unlikely (!checker.in_range (p))) return false;
uint8_t flag = *p++;
points_[i].flag = flag;
if ((flag & FLAG_REPEAT) != 0)
{
if (unlikely (!checker.in_range (p))) return false;
unsigned int repeat_count = *p++;
while ((repeat_count-- > 0) && (++i < num_points))
points_[i].flag = flag;
}
}
/* Read x & y coordinates */
return (read_points<x_setter_t> (p, points_, checker) &&
read_points<y_setter_t> (p, points_, checker));
}
else
{
/* empty glyph */
points_.resize (PHANTOM_COUNT);
for (unsigned int i = 0; i < points_.length; i++) points_[i].init ();
return true;
}
}
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); }
contour_point_t min;
contour_point_t max;
};
#ifndef HB_NO_VAR
/* Note: Recursively calls itself.
* all_points includes phantom points
*/
bool get_points_var (hb_codepoint_t glyph,
const int *coords, unsigned int coord_count,
contour_point_vector_t &all_points /* OUT */,
unsigned int depth=0) const
{
if (unlikely (depth++ > HB_MAX_NESTING_LEVEL)) return false;
contour_point_vector_t points;
hb_vector_t<unsigned int> end_points;
if (unlikely (!get_contour_points (glyph, points, end_points))) return false;
hb_array_t<contour_point_t> phantoms = points.sub_array (points.length - PHANTOM_COUNT, PHANTOM_COUNT);
init_phantom_points (glyph, phantoms);
if (unlikely (!face->table.gvar->apply_deltas_to_points (glyph, coords, coord_count, points.as_array (), end_points.as_array ()))) return false;
unsigned int comp_index = 0;
hb_bytes_t bytes = bytes_for_glyph (glyph);
const GlyphHeader &glyph_header = *bytes.as<GlyphHeader> ();
if (glyph_header.is_simple_glyph ())
all_points.extend (points.as_array ());
else if (glyph_header.is_composite_glyph ())
{
for (auto &item : get_composite_iterator (bytes))
{
contour_point_vector_t comp_points;
if (unlikely (!get_points_var (item.glyphIndex, coords, coord_count,
comp_points, depth))
|| comp_points.length < PHANTOM_COUNT)
return false;
/* Copy phantom points from component if USE_MY_METRICS flag set */
if (item.flags & CompositeGlyphHeader::USE_MY_METRICS)
for (unsigned int i = 0; i < PHANTOM_COUNT; i++)
phantoms[i] = comp_points[comp_points.length - PHANTOM_COUNT + i];
/* Apply component transformation & translation */
item.transform_points (comp_points);
/* Apply translatation from gvar */
comp_points.translate (points[comp_index]);
if (item.is_anchored ())
{
unsigned int p1, p2;
item.get_anchor_points (p1, p2);
if (likely (p1 < all_points.length && p2 < comp_points.length))
{
contour_point_t delta;
delta.init (all_points[p1].x - comp_points[p2].x,
all_points[p1].y - comp_points[p2].y);
comp_points.translate (delta);
}
}
all_points.extend (comp_points.sub_array (0, comp_points.length - PHANTOM_COUNT));
comp_index++;
}
all_points.extend (phantoms);
}
else return false;
return true;
}
bool get_var_extents_and_phantoms (hb_font_t *font, hb_codepoint_t glyph,
hb_glyph_extents_t *extents=nullptr /* OUT */,
contour_point_vector_t *phantoms=nullptr /* OUT */) const
{
contour_point_vector_t all_points;
if (unlikely (!get_points_var (glyph, font->coords, font->num_coords, all_points) ||
all_points.length < PHANTOM_COUNT)) return false;
/* Undocumented rasterizer behavior:
* Shift points horizontally by the updated left side bearing
*/
contour_point_t delta;
delta.init (-all_points[all_points.length - PHANTOM_COUNT + PHANTOM_LEFT].x, 0.f);
if (delta.x != 0.f) all_points.translate (delta);
if (extents != nullptr)
{
contour_bounds_t bounds;
for (unsigned int i = 0; i + PHANTOM_COUNT < all_points.length; i++)
bounds.add (all_points[i]);
if (bounds.min.x > bounds.max.x)
{
extents->width = 0;
extents->x_bearing = 0;
}
else
{
extents->x_bearing = font->em_scalef_x (bounds.min.x);
extents->width = font->em_scalef_x (bounds.max.x) - extents->x_bearing;
}
if (bounds.min.y > bounds.max.y)
{
extents->height = 0;
extents->y_bearing = 0;
}
else
{
extents->y_bearing = font->em_scalef_y (bounds.max.y);
extents->height = font->em_scalef_y (bounds.min.y) - extents->y_bearing;
}
}
if (phantoms != nullptr)
{
for (unsigned int i = 0; i < PHANTOM_COUNT; i++)
(*phantoms)[i] = all_points[all_points.length - PHANTOM_COUNT + i];
}
return true;
}
bool get_var_metrics (hb_font_t *font, hb_codepoint_t glyph,
contour_point_vector_t &phantoms) const
{ return get_var_extents_and_phantoms (font, glyph, nullptr, &phantoms); }
bool get_extents_var (hb_font_t *font, hb_codepoint_t glyph,
hb_glyph_extents_t *extents) const
{ return get_var_extents_and_phantoms (font, glyph, extents); }
#endif
public:
/* based on FontTools _g_l_y_f.py::trim */
bool remove_padding (unsigned int start_offset,
unsigned int *end_offset) const
{
unsigned int glyph_length = *end_offset - start_offset;
const char *glyph = ((const char *) glyf_table) + start_offset;
const GlyphHeader &glyph_header = *hb_bytes_t (glyph, glyph_length).as<GlyphHeader> ();
if (!glyph_header.has_data ()) return true;
const char *glyph_end = glyph + glyph_length;
if (glyph_header.is_composite_glyph ())
/* Trimming for composites not implemented.
* If removing hints it falls out of that. */
return true;
else
{
/* simple glyph w/contours, possibly trimmable */
glyph += GlyphHeader::SimpleHeader (glyph_header).instruction_len_offset ();
if (unlikely (glyph + 2 >= glyph_end)) return false;
uint16_t nCoordinates = (uint16_t) StructAtOffset<HBUINT16> (glyph - 2, 0) + 1;
uint16_t nInstructions = (uint16_t) StructAtOffset<HBUINT16> (glyph, 0);
glyph += 2 + nInstructions;
if (unlikely (glyph + 2 >= glyph_end)) return false;
unsigned int coordBytes = 0;
unsigned int coordsWithFlags = 0;
while (glyph < glyph_end)
{
uint8_t flag = (uint8_t) *glyph;
glyph++;
unsigned int repeat = 1;
if (flag & FLAG_REPEAT)
{
if (glyph >= glyph_end)
{
DEBUG_MSG (SUBSET, nullptr, "Bad flag");
return false;
}
repeat = ((uint8_t) *glyph) + 1;
glyph++;
}
unsigned int xBytes, yBytes;
xBytes = yBytes = 0;
if (flag & FLAG_X_SHORT) xBytes = 1;
else if ((flag & FLAG_X_SAME) == 0) xBytes = 2;
if (flag & FLAG_Y_SHORT) yBytes = 1;
else if ((flag & FLAG_Y_SAME) == 0) yBytes = 2;
coordBytes += (xBytes + yBytes) * repeat;
coordsWithFlags += repeat;
if (coordsWithFlags >= nCoordinates)
break;
}
if (coordsWithFlags != nCoordinates)
{
DEBUG_MSG (SUBSET, nullptr, "Expect %d coords to have flags, got flags for %d",
nCoordinates, coordsWithFlags);
return false;
}
glyph += coordBytes;
if (glyph < glyph_end)
*end_offset -= glyph_end - glyph;
}
return true;
}
bool get_offsets (hb_codepoint_t glyph,
unsigned int *start_offset /* OUT */,
unsigned int *end_offset /* OUT */) const
{
if (unlikely (glyph >= num_glyphs)) return false;
if (short_offset)
{
const HBUINT16 *offsets = (const HBUINT16 *) loca_table->dataZ.arrayZ;
*start_offset = 2 * offsets[glyph];
*end_offset = 2 * offsets[glyph + 1];
}
else
{
const HBUINT32 *offsets = (const HBUINT32 *) loca_table->dataZ.arrayZ;
*start_offset = offsets[glyph];
*end_offset = offsets[glyph + 1];
}
if (*start_offset > *end_offset || *end_offset > glyf_table.get_length ())
return false;
return true;
}
#ifndef HB_NO_VAR
unsigned int get_advance_var (hb_font_t *font, hb_codepoint_t glyph,
bool is_vertical) const
{
bool success = false;
contour_point_vector_t phantoms;
phantoms.resize (PHANTOM_COUNT);
if (likely (font->num_coords == face->table.gvar->get_axis_count ()))
success = get_var_metrics (font, glyph, phantoms);
if (unlikely (!success))
return is_vertical ? face->table.vmtx->get_advance (glyph) : face->table.hmtx->get_advance (glyph);
if (is_vertical)
return roundf (phantoms[PHANTOM_TOP].y - phantoms[PHANTOM_BOTTOM].y);
else
return roundf (phantoms[PHANTOM_RIGHT].x - phantoms[PHANTOM_LEFT].x);
}
int get_side_bearing_var (hb_font_t *font, hb_codepoint_t glyph, bool is_vertical) const
{
hb_glyph_extents_t extents;
contour_point_vector_t phantoms;
phantoms.resize (PHANTOM_COUNT);
if (unlikely (!get_var_extents_and_phantoms (font, glyph, &extents, &phantoms)))
return is_vertical ? face->table.vmtx->get_side_bearing (glyph) : face->table.hmtx->get_side_bearing (glyph);
return is_vertical ? ceil (phantoms[PHANTOM_TOP].y) - extents.y_bearing : floor (phantoms[PHANTOM_LEFT].x);
}
#endif
bool get_extents (hb_font_t *font, hb_codepoint_t glyph, hb_glyph_extents_t *extents) const
{
#ifndef HB_NO_VAR
unsigned int coord_count;
const int *coords = hb_font_get_var_coords_normalized (font, &coord_count);
if (coords && coord_count > 0 && coord_count == face->table.gvar->get_axis_count ())
return get_extents_var (font, glyph, extents);
#endif
if (unlikely (glyph >= num_glyphs)) return false;
const GlyphHeader &glyph_header = *bytes_for_glyph (glyph).as<GlyphHeader> ();
if (unlikely (!glyph_header.has_data ()))
return true; /* Empty glyph; zero extents. */
/* Undocumented rasterizer behavior: shift glyph to the left by (lsb - xMin), i.e., xMin = lsb */
/* extents->x_bearing = hb_min (glyph_header.xMin, glyph_header.xMax); */
extents->x_bearing = font->em_scale_x (face->table.hmtx->get_side_bearing (glyph));
extents->y_bearing = font->em_scale_x (hb_max (glyph_header.yMin, glyph_header.yMax));
extents->width = font->em_scale_x (hb_max (glyph_header.xMin, glyph_header.xMax) - hb_min (glyph_header.xMin, glyph_header.xMax));
extents->height = font->em_scale_x (hb_min (glyph_header.yMin, glyph_header.yMax) - extents->y_bearing);
return true;
}
hb_bytes_t bytes_for_glyph (hb_codepoint_t gid,
bool needs_padding_removal = false) const
{
unsigned int start_offset, end_offset;
if (unlikely (!get_offsets (gid, &start_offset, &end_offset)))
return hb_bytes_t ();
/* Remove padding, needed for subset */
if (needs_padding_removal)
if (unlikely (!remove_padding (start_offset, &end_offset)))
return hb_bytes_t ();
hb_bytes_t glyph_bytes = hb_bytes_t ((const char *) this->glyf_table + start_offset,
end_offset - start_offset);
/* Glyph size smaller than minimum header */
if (!glyph_bytes.as<GlyphHeader> ()->has_data ())
return hb_bytes_t ();
return glyph_bytes;
}
private:
bool short_offset;
unsigned int num_glyphs;
hb_blob_ptr_t<loca> loca_table;
hb_blob_ptr_t<glyf> glyf_table;
hb_face_t *face;
};
struct SubsetGlyph
{
hb_codepoint_t new_gid;
hb_codepoint_t old_gid;
hb_bytes_t source_glyph;
hb_bytes_t dest_start; /* region of source_glyph to copy first */
hb_bytes_t dest_end; /* region of source_glyph to copy second */
bool serialize (hb_serialize_context_t *c,
const hb_subset_plan_t *plan) const
{
TRACE_SERIALIZE (this);
hb_bytes_t dest_glyph = dest_start.copy (c);
dest_glyph = hb_bytes_t (&dest_glyph, dest_glyph.length + dest_end.copy (c).length);
unsigned int pad_length = padding ();
DEBUG_MSG (SUBSET, nullptr, "serialize %d byte glyph, width %d pad %d", dest_glyph.length, dest_glyph.length + pad_length, pad_length);
HBUINT8 pad;
pad = 0;
while (pad_length > 0)
{
c->embed (pad);
pad_length--;
}
if (dest_glyph.length)
{
_fix_component_gids (plan, dest_glyph);
if (plan->drop_hints)
{
_zero_instruction_length (dest_glyph);
c->check_success (_remove_composite_instruction_flag (dest_glyph));
}
}
return_trace (true);
}
void drop_hints (const OT::glyf::accelerator_t& glyf)
{
if (source_glyph.length == 0) return;
unsigned int instruction_len = 0;
const GlyphHeader& header = *source_glyph.as<GlyphHeader> ();
if (!header.get_instruction_length (source_glyph, &instruction_len))
/* Unable to read instruction length */
return;
if (header.is_composite_glyph ())
/* just chop instructions off the end for composite glyphs */
dest_start = hb_bytes_t (&source_glyph, source_glyph.length - instruction_len);
else
{
unsigned int glyph_length = GlyphHeader::SimpleHeader (header).length (instruction_len);
dest_start = hb_bytes_t (&source_glyph, glyph_length - instruction_len);
dest_end = hb_bytes_t (&source_glyph + glyph_length,
source_glyph.length - glyph_length);
}
}
unsigned int length () const { return dest_start.length + dest_end.length; }
/* pad to 2 to ensure 2-byte loca will be ok */
unsigned int padding () const { return length () % 2; }
unsigned int padded_size () const { return length () + padding (); }
};
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 {};
} /* namespace OT */
#endif /* HB_OT_GLYF_TABLE_HH */