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flutter / third_party / harfbuzz / 19d45dcab732f3a836e17d31be9ca92f01c818b0 / . / src / hb-ot-glyf-table.hh
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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 ((const char *) this,
subset_glyph.old_gid);
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)
{
OT::glyf::CompositeGlyphHeader::Iterator iterator;
if (OT::glyf::CompositeGlyphHeader::get_iterator (&glyph,
glyph.length,
&iterator))
{
do
{
hb_codepoint_t new_gid;
if (!plan->new_gid_for_old_gid (iterator.current->glyphIndex,
&new_gid))
continue;
((OT::glyf::CompositeGlyphHeader *) iterator.current)->glyphIndex = new_gid;
} while (iterator.move_to_next ());
}
}
static void
_zero_instruction_length (hb_bytes_t glyph)
{
const GlyphHeader &glyph_header = *glyph.as<GlyphHeader> ();
int16_t num_contours = (int16_t) glyph_header.numberOfContours;
if (num_contours <= 0) return; // only for simple glyphs
unsigned int contours_length = GlyphHeader::static_size + 2 * num_contours;
const HBUINT16 &instruction_length = StructAtOffset<HBUINT16> (&glyph,
contours_length);
(HBUINT16 &) instruction_length = 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 */
OT::glyf::CompositeGlyphHeader::Iterator composite_it;
if (unlikely (!OT::glyf::CompositeGlyphHeader::get_iterator (&glyph, glyph.length,
&composite_it)))
return false;
const OT::glyf::CompositeGlyphHeader *composite_header;
do
{
composite_header = composite_it.current;
OT::HBUINT16 *flags = const_cast<OT::HBUINT16 *> (&composite_header->flags);
*flags = (uint16_t) *flags & ~OT::glyf::CompositeGlyphHeader::WE_HAVE_INSTRUCTIONS;
} while (composite_it.move_to_next ());
return true;
}
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
{
unsigned int simple_instruction_len_offset () const
{ return static_size + 2 * numberOfContours; }
unsigned int simple_length (unsigned int instruction_len) const
{ return simple_instruction_len_offset () + 2 + instruction_len; }
bool is_composite_glyph () const { return numberOfContours < 0; }
bool is_simple_glyph () const { return numberOfContours > 0; }
bool has_data () const { return numberOfContours; }
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);
if (flags & WE_HAVE_A_SCALE)
{
matrix[0] = matrix[3] = ((const F2DOT14*)p)->to_float ();
return true;
}
else if (flags & WE_HAVE_AN_X_AND_Y_SCALE)
{
matrix[0] = ((const F2DOT14*)p)[0].to_float ();
matrix[3] = ((const F2DOT14*)p)[1].to_float ();
return true;
}
else if (flags & WE_HAVE_A_TWO_BY_TWO)
{
matrix[0] = ((const F2DOT14*)p)[0].to_float ();
matrix[1] = ((const F2DOT14*)p)[1].to_float ();
matrix[2] = ((const F2DOT14*)p)[2].to_float ();
matrix[3] = ((const F2DOT14*)p)[3].to_float ();
return true;
}
return tx || ty;
}
public:
// TODO rewrite using new iterator framework if possible
struct Iterator
{
const char *glyph_start;
const char *glyph_end;
const CompositeGlyphHeader *current;
bool move_to_next ()
{
if (current->flags & CompositeGlyphHeader::MORE_COMPONENTS)
{
const CompositeGlyphHeader *possible =
&StructAfter<CompositeGlyphHeader, CompositeGlyphHeader> (*current);
if (unlikely (!in_range (possible))) return false;
current = possible;
return true;
}
return false;
}
bool in_range (const CompositeGlyphHeader *composite) const
{
return (const char *) composite >= glyph_start
&& ((const char *) composite + CompositeGlyphHeader::min_size) <= glyph_end
&& ((const char *) composite + composite->get_size ()) <= glyph_end;
}
};
static bool get_iterator (const char * glyph_data,
unsigned int length,
CompositeGlyphHeader::Iterator *iterator /* OUT */)
{
const GlyphHeader &glyph_header = *hb_bytes_t (glyph_data, length).as<GlyphHeader> ();
if (!glyph_header.has_data ()) return false; /* Empty glyph; zero extents. */
if (glyph_header.is_composite_glyph ())
{
const CompositeGlyphHeader *possible =
&StructAfter<CompositeGlyphHeader, GlyphHeader> (glyph_header);
iterator->glyph_start = glyph_data;
iterator->glyph_end = (const char *) glyph_data + length;
if (!iterator->in_range (possible))
return false;
iterator->current = possible;
return true;
}
return false;
}
DEFINE_SIZE_MIN (4);
};
struct accelerator_t
{
void init (hb_face_t *face)
{
memset (this, 0, sizeof (accelerator_t));
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;
gvar_accel.init (face);
hmtx_accel.init (face);
vmtx_accel.init (face);
}
void fini ()
{
loca_table.destroy ();
glyf_table.destroy ();
gvar_accel.fini ();
hmtx_accel.fini ();
vmtx_accel.fini ();
}
/*
* Returns true if the referenced glyph is a valid glyph and a composite glyph.
* If true is returned a pointer to the composite glyph will be written into
* composite.
*/
bool get_composite (hb_codepoint_t glyph,
CompositeGlyphHeader::Iterator *composite /* OUT */) const
{
if (unlikely (!num_glyphs))
return false;
unsigned int start_offset, end_offset;
if (!get_offsets (glyph, &start_offset, &end_offset))
return false; /* glyph not found */
return CompositeGlyphHeader::get_iterator ((const char *) this->glyf_table + start_offset,
end_offset - start_offset,
composite);
}
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:
const GlyphHeader &get_header (hb_codepoint_t glyph) const
{
unsigned int start_offset, end_offset;
if (!get_offsets (glyph, &start_offset, &end_offset) || end_offset - start_offset < GlyphHeader::static_size)
return Null(GlyphHeader);
return StructAtOffset<GlyphHeader> (glyf_table, start_offset);
}
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) != 0; }
bool is_same (uint8_t flag) const { return (flag & FLAG_X_SAME) != 0; }
};
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) != 0; }
bool is_same (uint8_t flag) const { return (flag & FLAG_Y_SAME) != 0; }
};
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 = get_header (glyph);
int h_delta = (int)header.xMin - hmtx_accel.get_side_bearing (glyph);
int v_orig = (int)header.yMax + vmtx_accel.get_side_bearing (glyph);
unsigned int h_adv = hmtx_accel.get_advance (glyph);
unsigned int v_adv = vmtx_accel.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 = -(int)v_adv + v_orig;
}
/* 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;
unsigned int start_offset, end_offset;
if (unlikely (!get_offsets (glyph, &start_offset, &end_offset))) return false;
if (unlikely (end_offset - start_offset < GlyphHeader::static_size))
{
/* empty glyph */
points_.resize (PHANTOM_COUNT);
for (unsigned int i = 0; i < points_.length; i++) points_[i].init ();
return true;
}
CompositeGlyphHeader::Iterator composite;
if (get_composite (glyph, &composite))
{
/* For a composite glyph, add one pseudo point for each component */
do { num_points++; } while (composite.move_to_next());
points_.resize (num_points + PHANTOM_COUNT);
for (unsigned int i = 0; i < points_.length; i++) points_[i].init ();
return true;
}
const GlyphHeader &glyph_header = StructAtOffset<GlyphHeader> (glyf_table, start_offset);
int16_t num_contours = (int16_t) glyph_header.numberOfContours;
const HBUINT16 *end_pts = &StructAfter<HBUINT16, GlyphHeader> (glyph_header);
range_checker_t checker (glyf_table, start_offset, end_offset);
num_points = 0;
if (num_contours > 0)
{
if (unlikely (!checker.in_range (&end_pts[num_contours + 1]))) return false;
num_points = end_pts[num_contours - 1] + 1;
}
else if (num_contours < 0)
{
CompositeGlyphHeader::Iterator composite;
if (unlikely (!get_composite (glyph, &composite))) return false;
do
{
num_points++;
} while (composite.move_to_next());
}
points_.resize (num_points + PHANTOM_COUNT);
for (unsigned int i = 0; i < points_.length; i++) points_[i].init ();
if ((num_contours <= 0) || phantom_only) return true;
/* Read simple glyph points if !phantom_only */
end_points_.resize (num_contours);
for (int16_t 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));
}
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;
};
/* 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 (!gvar_accel.apply_deltas_to_points (glyph, coords, coord_count, points.as_array (), end_points.as_array ()))) return false;
unsigned int comp_index = 0;
CompositeGlyphHeader::Iterator composite;
if (!get_composite (glyph, &composite))
{
/* simple glyph */
all_points.extend (points.as_array ());
}
else
{
/* composite glyph */
do
{
contour_point_vector_t comp_points;
if (unlikely (!get_points_var (composite.current->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 (composite.current->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 */
composite.current->transform_points (comp_points);
/* Apply translatation from gvar */
comp_points.translate (points[comp_index]);
if (composite.current->is_anchored ())
{
unsigned int p1, p2;
composite.current->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++;
} while (composite.move_to_next());
all_points.extend (phantoms);
}
return true;
}
bool get_var_extents_and_phantoms (hb_codepoint_t glyph,
const int *coords, unsigned int coord_count,
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, coords, coord_count, 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 = (int32_t)floorf (bounds.min.x);
extents->width = (int32_t)ceilf (bounds.max.x) - extents->x_bearing;
}
if (bounds.min.y > bounds.max.y)
{
extents->height = 0;
extents->y_bearing = 0;
}
else
{
extents->y_bearing = (int32_t)ceilf (bounds.max.y);
extents->height = (int32_t)floorf (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_codepoint_t glyph,
const int *coords, unsigned int coord_count,
contour_point_vector_t &phantoms) const
{ return get_var_extents_and_phantoms (glyph, coords, coord_count, nullptr, &phantoms); }
bool get_extents_var (hb_codepoint_t glyph,
const int *coords, unsigned int coord_count,
hb_glyph_extents_t *extents) const
{ return get_var_extents_and_phantoms (glyph, coords, coord_count, extents); }
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 += glyph_header.simple_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;
}
bool get_instruction_length (hb_bytes_t glyph,
unsigned int * length /* OUT */) const
{
const GlyphHeader &glyph_header = *glyph.as<GlyphHeader> ();
/* Empty glyph; no instructions. */
if (!glyph_header.has_data ())
{
*length = 0;
// only 0 byte glyphs are healthy when missing GlyphHeader
return glyph.length == 0;
}
int16_t num_contours = (int16_t) glyph_header.numberOfContours;
if (num_contours < 0)
{
unsigned int start = glyph.length;
unsigned int end = glyph.length;
unsigned int glyph_offset = &glyph - glyf_table;
CompositeGlyphHeader::Iterator composite_it;
if (unlikely (!CompositeGlyphHeader::get_iterator (&glyph, glyph.length,
&composite_it)))
return false;
const CompositeGlyphHeader *last;
do
{
last = composite_it.current;
} while (composite_it.move_to_next ());
if ((uint16_t) last->flags & CompositeGlyphHeader::WE_HAVE_INSTRUCTIONS)
start = ((char *) last - (char *) glyf_table->dataZ.arrayZ)
+ last->get_size () - glyph_offset;
if (unlikely (start > end))
{
DEBUG_MSG (SUBSET, nullptr, "Invalid instruction offset, %d is outside "
"%d byte buffer", start, glyph.length);
return false;
}
*length = end - start;
}
else
{
unsigned int instruction_length_offset = GlyphHeader::static_size + 2 * num_contours;
if (unlikely (instruction_length_offset + 2 > glyph.length))
{
DEBUG_MSG(SUBSET, nullptr, "Glyph size is too short, missing field instructionLength.");
return false;
}
const HBUINT16 &instruction_len = StructAtOffset<HBUINT16> (&glyph, instruction_length_offset);
/* Out of bounds of the current glyph */
if (unlikely (glyph_header.simple_length (instruction_len) > glyph.length))
{
DEBUG_MSG(SUBSET, nullptr, "The instructions array overruns the glyph's boundaries.");
return false;
}
*length = (uint16_t) instruction_len;
}
return true;
}
unsigned int get_advance_var (hb_codepoint_t glyph,
const int *coords, unsigned int coord_count,
bool vertical) const
{
bool success = false;
contour_point_vector_t phantoms;
phantoms.resize (PHANTOM_COUNT);
if (likely (coord_count == gvar_accel.get_axis_count ()))
success = get_var_metrics (glyph, coords, coord_count, phantoms);
if (unlikely (!success))
return vertical? vmtx_accel.get_advance (glyph): hmtx_accel.get_advance (glyph);
if (vertical)
return (unsigned int)roundf (phantoms[PHANTOM_TOP].y - phantoms[PHANTOM_BOTTOM].y);
else
return (unsigned int)roundf (phantoms[PHANTOM_RIGHT].x - phantoms[PHANTOM_LEFT].x);
}
int get_side_bearing_var (hb_codepoint_t glyph, const int *coords, unsigned int coord_count, bool vertical) const
{
hb_glyph_extents_t extents;
contour_point_vector_t phantoms;
phantoms.resize (PHANTOM_COUNT);
if (unlikely (!get_var_extents_and_phantoms (glyph, coords, coord_count, &extents, &phantoms)))
return vertical? vmtx_accel.get_side_bearing (glyph): hmtx_accel.get_side_bearing (glyph);
return vertical? (int)ceilf (phantoms[PHANTOM_TOP].y) - extents.y_bearing: (int)floorf (phantoms[PHANTOM_LEFT].x);
}
bool get_extents (hb_font_t *font, hb_codepoint_t glyph, hb_glyph_extents_t *extents) const
{
unsigned int coord_count;
const int *coords = hb_font_get_var_coords_normalized (font, &coord_count);
if (coords && coord_count > 0 && coord_count == gvar_accel.get_axis_count ())
return get_extents_var (glyph, coords, coord_count, extents);
unsigned int start_offset, end_offset;
if (!get_offsets (glyph, &start_offset, &end_offset))
return false;
if (end_offset - start_offset < GlyphHeader::static_size)
return true; /* Empty glyph; zero extents. */
const GlyphHeader &glyph_header = StructAtOffset<GlyphHeader> (glyf_table, start_offset);
/* 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 = hmtx_accel.get_side_bearing (glyph);
extents->y_bearing = hb_max (glyph_header.yMin, glyph_header.yMax);
extents->width = hb_max (glyph_header.xMin, glyph_header.xMax) - hb_min (glyph_header.xMin, glyph_header.xMax);
extents->height = hb_min (glyph_header.yMin, glyph_header.yMax) - extents->y_bearing;
return true;
}
hb_bytes_t bytes_for_glyph (const char * glyf, hb_codepoint_t gid)
{
unsigned int start_offset, end_offset;
if (unlikely (!(get_offsets (gid, &start_offset, &end_offset) &&
remove_padding (start_offset, &end_offset))))
{
DEBUG_MSG(SUBSET, nullptr, "Unable to get offset or remove padding for %d", gid);
return hb_bytes_t ();
}
hb_bytes_t glyph_bytes = hb_bytes_t (glyf + start_offset, end_offset - start_offset);
if (!glyph_bytes.as<GlyphHeader> ()->has_data ())
{
DEBUG_MSG(SUBSET, nullptr, "Glyph size smaller than minimum header %d", gid);
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;
/* variable font support */
gvar::accelerator_t gvar_accel;
hmtx::accelerator_t hmtx_accel;
vmtx::accelerator_t vmtx_accel;
};
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;
if (!glyf.get_instruction_length (source_glyph, &instruction_len))
{
DEBUG_MSG (SUBSET, nullptr, "Unable to read instruction length for new_gid %d",
new_gid);
return;
}
const GlyphHeader& header = *source_glyph.as<GlyphHeader> ();
DEBUG_MSG (SUBSET, nullptr, "Unable to read instruction length for new_gid %d",
new_gid);
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 = header.simple_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);
DEBUG_MSG (SUBSET, nullptr, "source_len %d start len %d glyph_len %d "
"instruction_len %d end len %d",
source_glyph.length, dest_start.length, glyph_length,
instruction_len, dest_end.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 */