harfbuzz/src/hb-ot-var-hvar-table.hh

436 lines
13 KiB
C++

/*
* Copyright © 2017 Google, Inc.
*
* 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
*/
#ifndef HB_OT_VAR_HVAR_TABLE_HH
#define HB_OT_VAR_HVAR_TABLE_HH
#include "hb-ot-layout-common.hh"
namespace OT {
struct DeltaSetIndexMap
{
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) &&
c->check_range (mapDataZ.arrayZ,
mapCount,
get_width ()));
}
template <typename T>
bool serialize (hb_serialize_context_t *c, const T &plan)
{
unsigned int width = plan.get_width ();
unsigned int inner_bit_count = plan.get_inner_bit_count ();
const hb_array_t<const unsigned int> output_map = plan.get_output_map ();
TRACE_SERIALIZE (this);
if (unlikely (output_map.length && ((((inner_bit_count-1)&~0xF)!=0) || (((width-1)&~0x3)!=0))))
return_trace (false);
if (unlikely (!c->extend_min (*this))) return_trace (false);
format.set (((width-1)<<4)|(inner_bit_count-1));
mapCount.set (output_map.length);
HBUINT8 *p = c->allocate_size<HBUINT8> (width * output_map.length);
if (unlikely (!p)) return_trace (false);
for (unsigned int i = 0; i < output_map.length; i++)
{
unsigned int v = output_map[i];
unsigned int outer = v >> 16;
unsigned int inner = v & 0xFFFF;
unsigned int u = (outer << inner_bit_count)|inner;
for (unsigned int w = width; w > 0;)
{
p[--w].set (u);
u >>= 8;
}
p += width;
}
return_trace (true);
}
unsigned int map (unsigned int v) const /* Returns 16.16 outer.inner. */
{
/* If count is zero, pass value unchanged. This takes
* care of direct mapping for advance map. */
if (!mapCount)
return v;
if (v >= mapCount)
v = mapCount - 1;
unsigned int u = 0;
{ /* Fetch it. */
unsigned int w = get_width ();
const HBUINT8 *p = mapDataZ.arrayZ + w * v;
for (; w; w--)
u = (u << 8) + *p++;
}
{ /* Repack it. */
unsigned int n = get_inner_bit_count ();
unsigned int outer = u >> n;
unsigned int inner = u & ((1 << n) - 1);
u = (outer<<16) | inner;
}
return u;
}
unsigned int get_map_count () const { return mapCount; }
unsigned int get_width () const { return ((format >> 4) & 3) + 1; }
unsigned int get_inner_bit_count () const { return (format & 0xF) + 1; }
protected:
HBUINT16 format; /* A packed field that describes the compressed
* representation of delta-set indices. */
HBUINT16 mapCount; /* The number of mapping entries. */
UnsizedArrayOf<HBUINT8>
mapDataZ; /* The delta-set index mapping data. */
public:
DEFINE_SIZE_ARRAY (4, mapDataZ);
};
struct index_map_subset_plan_t
{
void init (const DeltaSetIndexMap &index_map,
hb_bimap_t &outer_remap,
hb_vector_t<hb_bimap_t> &inner_remaps,
const hb_subset_plan_t *plan)
{
map_count = 0;
outer_bit_count = 0;
inner_bit_count = 0;
max_inners.init ();
output_map.init ();
/* Identity map */
if (&index_map == &Null(DeltaSetIndexMap))
return;
unsigned int last_val = (unsigned int)-1;
hb_codepoint_t last_gid = (hb_codepoint_t)-1;
hb_codepoint_t gid = (hb_codepoint_t)index_map.get_map_count ();
outer_bit_count = (index_map.get_width () * 8) - index_map.get_inner_bit_count ();
max_inners.resize (inner_remaps.length);
for (unsigned i = 0; i < inner_remaps.length; i++) max_inners[i] = 0;
/* Search backwards for a map value different from the last map value */
for (; gid > 0; gid--)
{
hb_codepoint_t old_gid;
if (!plan->old_gid_for_new_gid (gid - 1, &old_gid))
continue;
unsigned int v = index_map.map (old_gid);
if (last_gid == (hb_codepoint_t)-1)
{
last_val = v;
last_gid = gid;
continue;
}
if (v != last_val) break;
last_gid = gid;
}
map_count = last_gid + 1;
for (gid = 0; gid < map_count; gid++)
{
hb_codepoint_t old_gid;
if (!plan->old_gid_for_new_gid (gid, &old_gid))
continue;
unsigned int v = index_map.map (old_gid);
unsigned int outer = v >> 16;
unsigned int inner = v & 0xFFFF;
outer_remap.add (outer);
if (inner > max_inners[outer]) max_inners[outer] = inner;
inner_remaps[outer].add (inner);
}
}
void fini ()
{
max_inners.fini ();
output_map.fini ();
}
void remap (const hb_subset_plan_t *plan,
const DeltaSetIndexMap *input_map,
const hb_bimap_t &outer_remap,
const hb_vector_t<hb_bimap_t> &inner_remaps)
{
for (unsigned int i = 0; i < max_inners.length; i++)
{
if (inner_remaps[i].get_count () == 0) continue;
unsigned int bit_count = hb_bit_storage (inner_remaps[i][max_inners[i]]);
if (bit_count > inner_bit_count) inner_bit_count = bit_count;
}
output_map.resize (map_count);
for (hb_codepoint_t gid = 0; gid < output_map.length; gid++)
{
hb_codepoint_t old_gid = 0;
(void)plan->old_gid_for_new_gid (gid, &old_gid);
unsigned int v = input_map->map (old_gid);
unsigned int outer = v >> 16;
output_map[gid] = (outer_remap[outer] << 16) | (inner_remaps[outer][v & 0xFFFF]);
}
}
unsigned int get_inner_bit_count () const { return inner_bit_count; }
unsigned int get_width () const { return ((outer_bit_count + inner_bit_count + 7) / 8); }
unsigned int get_map_count () const { return map_count; }
unsigned int get_size () const
{ return (map_count? (DeltaSetIndexMap::min_size + get_width () * map_count): 0); }
hb_array_t<const unsigned int> get_output_map () const { return output_map.as_array (); }
protected:
unsigned int map_count;
hb_vector_t<unsigned int>
max_inners;
unsigned int outer_bit_count;
unsigned int inner_bit_count;
hb_vector_t<unsigned int>
output_map;
};
struct hvarvvar_subset_plan_t
{
hvarvvar_subset_plan_t() : inner_remaps (), index_map_plans () {}
~hvarvvar_subset_plan_t() { fini (); }
void init (const hb_array_t<const DeltaSetIndexMap *> &index_maps,
const VariationStore &_var_store,
const hb_subset_plan_t *plan)
{
index_map_plans.resize (index_maps.length);
var_store = &_var_store;
inner_remaps.resize (var_store->get_sub_table_count ());
for (unsigned int i = 0; i < inner_remaps.length; i++)
inner_remaps[i].init ();
for (unsigned int i = 0; i < index_maps.length; i++)
index_map_plans[i].init (*index_maps[i], outer_remap, inner_remaps, plan);
outer_remap.reorder ();
for (unsigned int i = 0; i < inner_remaps.length; i++)
if (inner_remaps[i].get_count () > 0) inner_remaps[i].reorder ();
for (unsigned int i = 0; i < index_maps.length; i++)
index_map_plans[i].remap (plan, index_maps[i], outer_remap, inner_remaps);
}
void fini ()
{
inner_remaps.fini_deep ();
index_map_plans.fini_deep ();
}
hb_bimap_t outer_remap;
hb_vector_t<hb_bimap_t> inner_remaps;
hb_vector_t<index_map_subset_plan_t>
index_map_plans;
const VariationStore *var_store;
};
/*
* HVAR -- Horizontal Metrics Variations
* https://docs.microsoft.com/en-us/typography/opentype/spec/hvar
* VVAR -- Vertical Metrics Variations
* https://docs.microsoft.com/en-us/typography/opentype/spec/vvar
*/
#define HB_OT_TAG_HVAR HB_TAG('H','V','A','R')
#define HB_OT_TAG_VVAR HB_TAG('V','V','A','R')
struct HVARVVAR
{
static constexpr hb_tag_t HVARTag = HB_OT_TAG_HVAR;
static constexpr hb_tag_t VVARTag = HB_OT_TAG_VVAR;
enum index_map_index_t {
ADV_INDEX,
LSB_INDEX,
RSB_INDEX,
TSB_INDEX,
VORG_INDEX
};
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (version.sanitize (c) &&
likely (version.major == 1) &&
varStore.sanitize (c, this) &&
advMap.sanitize (c, this) &&
lsbMap.sanitize (c, this) &&
rsbMap.sanitize (c, this));
}
void listup_index_maps (hb_vector_t<const DeltaSetIndexMap *> &index_maps) const
{
index_maps.push (&(this+advMap));
index_maps.push (&(this+lsbMap));
index_maps.push (&(this+rsbMap));
}
bool serialize_index_maps (hb_serialize_context_t *c,
const hb_array_t<index_map_subset_plan_t> &im_plans)
{
TRACE_SUBSET (this);
if (!im_plans[ADV_INDEX].get_map_count ())
advMap.set (0);
else if (unlikely (!advMap.serialize (c, this).serialize (c, im_plans[ADV_INDEX])))
return_trace (false);
if (!im_plans[LSB_INDEX].get_map_count ())
lsbMap.set (0);
else if (unlikely (!lsbMap.serialize (c, this).serialize (c, im_plans[LSB_INDEX])))
return_trace (false);
if (!im_plans[RSB_INDEX].get_map_count ())
rsbMap.set (0);
else if (unlikely (!rsbMap.serialize (c, this).serialize (c, im_plans[RSB_INDEX])))
return_trace (false);
return_trace (true);
}
template <typename T>
bool _subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
hvarvvar_subset_plan_t hvar_plan;
hb_vector_t<const DeltaSetIndexMap *>
index_maps;
((T*)this)->listup_index_maps (index_maps);
hvar_plan.init (index_maps.as_array (), this+varStore, c->plan);
T *out = c->serializer->allocate_min<T> ();
if (unlikely (!out)) return_trace (false);
out->version.major.set (1);
out->version.minor.set (0);
if (!unlikely (out->varStore.serialize (c->serializer, out)
.serialize (c->serializer, hvar_plan.var_store, hvar_plan.inner_remaps.as_array ())))
return_trace (false);
return_trace (out->T::serialize_index_maps (c->serializer,
hvar_plan.index_map_plans.as_array ()));
}
float get_advance_var (hb_codepoint_t glyph,
const int *coords, unsigned int coord_count) const
{
unsigned int varidx = (this+advMap).map (glyph);
return (this+varStore).get_delta (varidx, coords, coord_count);
}
float get_side_bearing_var (hb_codepoint_t glyph,
const int *coords, unsigned int coord_count) const
{
if (!has_side_bearing_deltas ()) return 0.f;
unsigned int varidx = (this+lsbMap).map (glyph);
return (this+varStore).get_delta (varidx, coords, coord_count);
}
bool has_side_bearing_deltas () const { return lsbMap && rsbMap; }
protected:
FixedVersion<>version; /* Version of the metrics variation table
* initially set to 0x00010000u */
LOffsetTo<VariationStore>
varStore; /* Offset to item variation store table. */
LOffsetTo<DeltaSetIndexMap>
advMap; /* Offset to advance var-idx mapping. */
LOffsetTo<DeltaSetIndexMap>
lsbMap; /* Offset to lsb/tsb var-idx mapping. */
LOffsetTo<DeltaSetIndexMap>
rsbMap; /* Offset to rsb/bsb var-idx mapping. */
public:
DEFINE_SIZE_STATIC (20);
};
struct HVAR : HVARVVAR {
static constexpr hb_tag_t tableTag = HB_OT_TAG_HVAR;
bool subset (hb_subset_context_t *c) const { return HVARVVAR::_subset<HVAR> (c); }
};
struct VVAR : HVARVVAR {
static constexpr hb_tag_t tableTag = HB_OT_TAG_VVAR;
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (static_cast<const HVARVVAR *> (this)->sanitize (c) &&
vorgMap.sanitize (c, this));
}
void listup_index_maps (hb_vector_t<const DeltaSetIndexMap *> &index_maps) const
{
HVARVVAR::listup_index_maps (index_maps);
index_maps.push (&(this+vorgMap));
}
bool serialize_index_maps (hb_serialize_context_t *c,
const hb_array_t<index_map_subset_plan_t> &im_plans)
{
TRACE_SUBSET (this);
if (unlikely (!HVARVVAR::serialize_index_maps (c, im_plans)))
return_trace (false);
if (!im_plans[VORG_INDEX].get_map_count ())
vorgMap.set (0);
else if (unlikely (!vorgMap.serialize (c, this).serialize (c, im_plans[VORG_INDEX])))
return_trace (false);
return_trace (true);
}
bool subset (hb_subset_context_t *c) const { return HVARVVAR::_subset<VVAR> (c); }
protected:
LOffsetTo<DeltaSetIndexMap>
vorgMap; /* Offset to vertical-origin var-idx mapping. */
public:
DEFINE_SIZE_STATIC (24);
};
} /* namespace OT */
#endif /* HB_OT_VAR_HVAR_TABLE_HH */