harfbuzz/src/hb-ot-layout-gsub-private.hh

947 lines
25 KiB
C++

/*
* Copyright (C) 2007,2008,2009,2010 Red Hat, 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.
*
* Red Hat Author(s): Behdad Esfahbod
*/
#ifndef HB_OT_LAYOUT_GSUB_PRIVATE_HH
#define HB_OT_LAYOUT_GSUB_PRIVATE_HH
#include "hb-ot-layout-gsubgpos-private.hh"
#undef BUFFER
#define BUFFER context->buffer
struct SingleSubstFormat1
{
friend struct SingleSubst;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
hb_codepoint_t glyph_id = IN_CURGLYPH ();
unsigned int index = (this+coverage) (glyph_id);
if (likely (index == NOT_COVERED))
return false;
glyph_id += deltaGlyphID;
_hb_buffer_replace_glyph (context->buffer, glyph_id);
/* We inherit the old glyph class to the substituted glyph */
if (_hb_ot_layout_has_new_glyph_classes (context->layout->face))
_hb_ot_layout_set_glyph_property (context->layout->face, glyph_id, context->property);
return true;
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
return coverage.sanitize (context, this)
&& deltaGlyphID.sanitize (context);
}
private:
USHORT format; /* Format identifier--format = 1 */
OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of Substitution table */
SHORT deltaGlyphID; /* Add to original GlyphID to get
* substitute GlyphID */
public:
DEFINE_SIZE_STATIC (6);
};
struct SingleSubstFormat2
{
friend struct SingleSubst;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
hb_codepoint_t glyph_id = IN_CURGLYPH ();
unsigned int index = (this+coverage) (glyph_id);
if (likely (index == NOT_COVERED))
return false;
if (unlikely (index >= substitute.len))
return false;
glyph_id = substitute[index];
_hb_buffer_replace_glyph (context->buffer, glyph_id);
/* We inherit the old glyph class to the substituted glyph */
if (_hb_ot_layout_has_new_glyph_classes (context->layout->face))
_hb_ot_layout_set_glyph_property (context->layout->face, glyph_id, context->property);
return true;
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
return coverage.sanitize (context, this)
&& substitute.sanitize (context);
}
private:
USHORT format; /* Format identifier--format = 2 */
OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of Substitution table */
ArrayOf<GlyphID>
substitute; /* Array of substitute
* GlyphIDs--ordered by Coverage Index */
public:
DEFINE_SIZE_ARRAY (6, substitute);
};
struct SingleSubst
{
friend struct SubstLookupSubTable;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
switch (u.format) {
case 1: return u.format1.apply (context);
case 2: return u.format2.apply (context);
default:return false;
}
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
if (!u.format.sanitize (context)) return false;
switch (u.format) {
case 1: return u.format1.sanitize (context);
case 2: return u.format2.sanitize (context);
default:return true;
}
}
private:
union {
USHORT format; /* Format identifier */
SingleSubstFormat1 format1;
SingleSubstFormat2 format2;
} u;
};
struct Sequence
{
friend struct MultipleSubstFormat1;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
if (unlikely (!substitute.len))
return false;
_hb_buffer_add_output_glyphs_be16 (context->buffer, 1,
substitute.len, (const uint16_t *) substitute.array,
0xFFFF, 0xFFFF);
/* This is a guess only ... */
if (_hb_ot_layout_has_new_glyph_classes (context->layout->face))
{
unsigned int property = context->property;
if (property == HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE)
property = HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH;
unsigned int count = substitute.len;
for (unsigned int n = 0; n < count; n++)
_hb_ot_layout_set_glyph_property (context->layout->face, substitute[n], property);
}
return true;
}
public:
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
return substitute.sanitize (context);
}
private:
ArrayOf<GlyphID>
substitute; /* String of GlyphIDs to substitute */
public:
DEFINE_SIZE_ARRAY (2, substitute);
};
struct MultipleSubstFormat1
{
friend struct MultipleSubst;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
unsigned int index = (this+coverage) (IN_CURGLYPH ());
if (likely (index == NOT_COVERED))
return false;
return (this+sequence[index]).apply (context);
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
return coverage.sanitize (context, this)
&& sequence.sanitize (context, this);
}
private:
USHORT format; /* Format identifier--format = 1 */
OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of Substitution table */
OffsetArrayOf<Sequence>
sequence; /* Array of Sequence tables
* ordered by Coverage Index */
public:
DEFINE_SIZE_ARRAY (6, sequence);
};
struct MultipleSubst
{
friend struct SubstLookupSubTable;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
switch (u.format) {
case 1: return u.format1.apply (context);
default:return false;
}
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
if (!u.format.sanitize (context)) return false;
switch (u.format) {
case 1: return u.format1.sanitize (context);
default:return true;
}
}
private:
union {
USHORT format; /* Format identifier */
MultipleSubstFormat1 format1;
} u;
};
typedef ArrayOf<GlyphID> AlternateSet; /* Array of alternate GlyphIDs--in
* arbitrary order */
struct AlternateSubstFormat1
{
friend struct AlternateSubst;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
hb_codepoint_t glyph_id = IN_CURGLYPH ();
unsigned int index = (this+coverage) (glyph_id);
if (likely (index == NOT_COVERED))
return false;
const AlternateSet &alt_set = this+alternateSet[index];
if (unlikely (!alt_set.len))
return false;
unsigned int alt_index = 0;
/* XXX callback to user to choose alternate
if (context->layout->face->altfunc)
alt_index = (context->layout->face->altfunc)(context->layout->layout, context->buffer,
context->buffer->out_pos, glyph_id,
alt_set.len, alt_set.array);
*/
if (unlikely (alt_index >= alt_set.len))
return false;
glyph_id = alt_set[alt_index];
_hb_buffer_replace_glyph (context->buffer, glyph_id);
/* We inherit the old glyph class to the substituted glyph */
if (_hb_ot_layout_has_new_glyph_classes (context->layout->face))
_hb_ot_layout_set_glyph_property (context->layout->face, glyph_id, context->property);
return true;
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
return coverage.sanitize (context, this)
&& alternateSet.sanitize (context, this);
}
private:
USHORT format; /* Format identifier--format = 1 */
OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of Substitution table */
OffsetArrayOf<AlternateSet>
alternateSet; /* Array of AlternateSet tables
* ordered by Coverage Index */
public:
DEFINE_SIZE_ARRAY (6, alternateSet);
};
struct AlternateSubst
{
friend struct SubstLookupSubTable;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
switch (u.format) {
case 1: return u.format1.apply (context);
default:return false;
}
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
if (!u.format.sanitize (context)) return false;
switch (u.format) {
case 1: return u.format1.sanitize (context);
default:return true;
}
}
private:
union {
USHORT format; /* Format identifier */
AlternateSubstFormat1 format1;
} u;
};
struct Ligature
{
friend struct LigatureSet;
private:
inline bool apply (hb_apply_context_t *context, bool is_mark) const
{
TRACE_APPLY ();
unsigned int i, j;
unsigned int count = component.len;
unsigned int end = MIN (context->buffer->in_length, context->buffer->in_pos + context->context_length);
if (unlikely (context->buffer->in_pos + count > end))
return false;
for (i = 1, j = context->buffer->in_pos + 1; i < count; i++, j++)
{
unsigned int property;
while (_hb_ot_layout_skip_mark (context->layout->face, IN_INFO (j), context->lookup_flag, &property))
{
if (unlikely (j + count - i == end))
return false;
j++;
}
if (!(property & HB_OT_LAYOUT_GLYPH_CLASS_MARK))
is_mark = false;
if (likely (IN_GLYPH (j) != component[i]))
return false;
}
/* This is just a guess ... */
if (_hb_ot_layout_has_new_glyph_classes (context->layout->face))
_hb_ot_layout_set_glyph_class (context->layout->face, ligGlyph,
is_mark ? HB_OT_LAYOUT_GLYPH_CLASS_MARK
: HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE);
if (j == context->buffer->in_pos + i) /* No input glyphs skipped */
/* We don't use a new ligature ID if there are no skipped
glyphs and the ligature already has an ID. */
_hb_buffer_add_output_glyphs_be16 (context->buffer, i,
1, (const uint16_t *) &ligGlyph,
0,
IN_LIGID (context->buffer->in_pos) && !IN_COMPONENT (context->buffer->in_pos) ?
0xFFFF : _hb_buffer_allocate_lig_id (context->buffer));
else
{
unsigned int lig_id = _hb_buffer_allocate_lig_id (context->buffer);
_hb_buffer_add_output_glyph (context->buffer, ligGlyph, 0xFFFF, lig_id);
/* Now we must do a second loop to copy the skipped glyphs to
`out' and assign component values to it. We start with the
glyph after the first component. Glyphs between component
i and i+1 belong to component i. Together with the lig_id
value it is later possible to check whether a specific
component value really belongs to a given ligature. */
for ( i = 1; i < count; i++ )
{
while (_hb_ot_layout_skip_mark (context->layout->face, IN_CURINFO (), context->lookup_flag, NULL))
_hb_buffer_add_output_glyph (context->buffer, IN_CURGLYPH (), i, lig_id);
(context->buffer->in_pos)++;
}
}
return true;
}
public:
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
return ligGlyph.sanitize (context)
&& component.sanitize (context);
}
private:
GlyphID ligGlyph; /* GlyphID of ligature to substitute */
HeadlessArrayOf<GlyphID>
component; /* Array of component GlyphIDs--start
* with the second component--ordered
* in writing direction */
public:
DEFINE_SIZE_ARRAY (4, component);
};
struct LigatureSet
{
friend struct LigatureSubstFormat1;
private:
inline bool apply (hb_apply_context_t *context, bool is_mark) const
{
TRACE_APPLY ();
unsigned int num_ligs = ligature.len;
for (unsigned int i = 0; i < num_ligs; i++)
{
const Ligature &lig = this+ligature[i];
if (lig.apply (context, is_mark))
return true;
}
return false;
}
public:
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
return ligature.sanitize (context, this);
}
private:
OffsetArrayOf<Ligature>
ligature; /* Array LigatureSet tables
* ordered by preference */
public:
DEFINE_SIZE_ARRAY (2, ligature);
};
struct LigatureSubstFormat1
{
friend struct LigatureSubst;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
hb_codepoint_t glyph_id = IN_CURGLYPH ();
bool first_is_mark = !!(context->property & HB_OT_LAYOUT_GLYPH_CLASS_MARK);
unsigned int index = (this+coverage) (glyph_id);
if (likely (index == NOT_COVERED))
return false;
const LigatureSet &lig_set = this+ligatureSet[index];
return lig_set.apply (context, first_is_mark);
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
return coverage.sanitize (context, this)
&& ligatureSet.sanitize (context, this);
}
private:
USHORT format; /* Format identifier--format = 1 */
OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of Substitution table */
OffsetArrayOf<LigatureSet>
ligatureSet; /* Array LigatureSet tables
* ordered by Coverage Index */
public:
DEFINE_SIZE_ARRAY (6, ligatureSet);
};
struct LigatureSubst
{
friend struct SubstLookupSubTable;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
switch (u.format) {
case 1: return u.format1.apply (context);
default:return false;
}
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
if (!u.format.sanitize (context)) return false;
switch (u.format) {
case 1: return u.format1.sanitize (context);
default:return true;
}
}
private:
union {
USHORT format; /* Format identifier */
LigatureSubstFormat1 format1;
} u;
};
static inline bool substitute_lookup (hb_apply_context_t *context, unsigned int lookup_index);
struct ContextSubst : Context
{
friend struct SubstLookupSubTable;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
return Context::apply (context, substitute_lookup);
}
};
struct ChainContextSubst : ChainContext
{
friend struct SubstLookupSubTable;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
return ChainContext::apply (context, substitute_lookup);
}
};
struct ExtensionSubst : Extension
{
friend struct SubstLookupSubTable;
friend struct SubstLookup;
private:
inline const struct SubstLookupSubTable& get_subtable (void) const
{
unsigned int offset = get_offset ();
if (unlikely (!offset)) return Null(SubstLookupSubTable);
return StructAtOffset<SubstLookupSubTable> (this, offset);
}
inline bool apply (hb_apply_context_t *context) const;
inline bool sanitize (hb_sanitize_context_t *context);
inline bool is_reverse (void) const;
};
struct ReverseChainSingleSubstFormat1
{
friend struct ReverseChainSingleSubst;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
if (unlikely (context->context_length != NO_CONTEXT))
return false; /* No chaining to this type */
unsigned int index = (this+coverage) (IN_CURGLYPH ());
if (likely (index == NOT_COVERED))
return false;
const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
if (match_backtrack (context,
backtrack.len, (USHORT *) backtrack.array,
match_coverage, this) &&
match_lookahead (context,
lookahead.len, (USHORT *) lookahead.array,
match_coverage, this,
1))
{
IN_CURGLYPH () = substitute[index];
context->buffer->in_pos--; /* Reverse! */
return true;
}
return false;
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
if (!(coverage.sanitize (context, this)
&& backtrack.sanitize (context, this)))
return false;
OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
if (!lookahead.sanitize (context, this))
return false;
ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
return substitute.sanitize (context);
}
private:
USHORT format; /* Format identifier--format = 1 */
OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of table */
OffsetArrayOf<Coverage>
backtrack; /* Array of coverage tables
* in backtracking sequence, in glyph
* sequence order */
OffsetArrayOf<Coverage>
lookaheadX; /* Array of coverage tables
* in lookahead sequence, in glyph
* sequence order */
ArrayOf<GlyphID>
substituteX; /* Array of substitute
* GlyphIDs--ordered by Coverage Index */
public:
DEFINE_SIZE_MIN (10);
};
struct ReverseChainSingleSubst
{
friend struct SubstLookupSubTable;
private:
inline bool apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
switch (u.format) {
case 1: return u.format1.apply (context);
default:return false;
}
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
if (!u.format.sanitize (context)) return false;
switch (u.format) {
case 1: return u.format1.sanitize (context);
default:return true;
}
}
private:
union {
USHORT format; /* Format identifier */
ReverseChainSingleSubstFormat1 format1;
} u;
};
/*
* SubstLookup
*/
struct SubstLookupSubTable
{
friend struct SubstLookup;
enum {
Single = 1,
Multiple = 2,
Alternate = 3,
Ligature = 4,
Context = 5,
ChainContext = 6,
Extension = 7,
ReverseChainSingle = 8
};
inline bool apply (hb_apply_context_t *context, unsigned int lookup_type) const
{
TRACE_APPLY ();
switch (lookup_type) {
case Single: return u.single.apply (context);
case Multiple: return u.multiple.apply (context);
case Alternate: return u.alternate.apply (context);
case Ligature: return u.ligature.apply (context);
case Context: return u.context.apply (context);
case ChainContext: return u.chainContext.apply (context);
case Extension: return u.extension.apply (context);
case ReverseChainSingle: return u.reverseChainContextSingle.apply (context);
default:return false;
}
}
inline bool sanitize (hb_sanitize_context_t *context, unsigned int lookup_type) {
TRACE_SANITIZE ();
switch (lookup_type) {
case Single: return u.single.sanitize (context);
case Multiple: return u.multiple.sanitize (context);
case Alternate: return u.alternate.sanitize (context);
case Ligature: return u.ligature.sanitize (context);
case Context: return u.context.sanitize (context);
case ChainContext: return u.chainContext.sanitize (context);
case Extension: return u.extension.sanitize (context);
case ReverseChainSingle: return u.reverseChainContextSingle.sanitize (context);
default:return true;
}
}
private:
union {
USHORT sub_format;
SingleSubst single;
MultipleSubst multiple;
AlternateSubst alternate;
LigatureSubst ligature;
ContextSubst context;
ChainContextSubst chainContext;
ExtensionSubst extension;
ReverseChainSingleSubst reverseChainContextSingle;
} u;
public:
DEFINE_SIZE_UNION (2, sub_format);
};
struct SubstLookup : Lookup
{
inline const SubstLookupSubTable& get_subtable (unsigned int i) const
{ return this+CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable)[i]; }
inline static bool lookup_type_is_reverse (unsigned int lookup_type)
{ return lookup_type == SubstLookupSubTable::ReverseChainSingle; }
inline bool is_reverse (void) const
{
unsigned int type = get_type ();
if (unlikely (type == SubstLookupSubTable::Extension))
return CastR<ExtensionSubst> (get_subtable(0)).is_reverse ();
return lookup_type_is_reverse (type);
}
inline bool apply_once (hb_ot_layout_context_t *layout,
hb_buffer_t *buffer,
unsigned int context_length,
unsigned int nesting_level_left) const
{
unsigned int lookup_type = get_type ();
hb_apply_context_t context[1] = {{0}};
context->layout = layout;
context->buffer = buffer;
context->context_length = context_length;
context->nesting_level_left = nesting_level_left;
context->lookup_flag = get_flag ();
if (!_hb_ot_layout_check_glyph_property (context->layout->face, IN_CURINFO (), context->lookup_flag, &context->property))
return false;
if (unlikely (lookup_type == SubstLookupSubTable::Extension))
{
/* The spec says all subtables should have the same type.
* This is specially important if one has a reverse type!
*
* This is rather slow to do this here for every glyph,
* but it's easiest, and who uses extension lookups anyway?!*/
unsigned int count = get_subtable_count ();
unsigned int type = get_subtable(0).u.extension.get_type ();
for (unsigned int i = 1; i < count; i++)
if (get_subtable(i).u.extension.get_type () != type)
return false;
}
unsigned int count = get_subtable_count ();
for (unsigned int i = 0; i < count; i++)
if (get_subtable (i).apply (context, lookup_type))
return true;
return false;
}
inline bool apply_string (hb_ot_layout_context_t *layout,
hb_buffer_t *buffer,
hb_mask_t mask) const
{
#undef BUFFER
#define BUFFER buffer
bool ret = false;
if (unlikely (!buffer->in_length))
return false;
if (likely (!is_reverse ()))
{
/* in/out forward substitution */
_hb_buffer_clear_output (buffer);
buffer->in_pos = 0;
while (buffer->in_pos < buffer->in_length)
{
if ((~IN_MASK (buffer->in_pos) & mask) &&
apply_once (layout, buffer, NO_CONTEXT, MAX_NESTING_LEVEL))
ret = true;
else
_hb_buffer_next_glyph (buffer);
}
if (ret)
_hb_buffer_swap (buffer);
}
else
{
/* in-place backward substitution */
buffer->in_pos = buffer->in_length - 1;
do
{
if ((~IN_MASK (buffer->in_pos) & mask) &&
apply_once (layout, buffer, NO_CONTEXT, MAX_NESTING_LEVEL))
ret = true;
else
buffer->in_pos--;
}
while ((int) buffer->in_pos >= 0);
}
return ret;
}
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
if (unlikely (!Lookup::sanitize (context))) return false;
OffsetArrayOf<SubstLookupSubTable> &list = CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable);
return list.sanitize (context, this, get_type ());
}
};
typedef OffsetListOf<SubstLookup> SubstLookupList;
/*
* GSUB
*/
struct GSUB : GSUBGPOS
{
static const hb_tag_t Tag = HB_OT_TAG_GSUB;
inline const SubstLookup& get_lookup (unsigned int i) const
{ return CastR<SubstLookup> (GSUBGPOS::get_lookup (i)); }
inline bool substitute_lookup (hb_ot_layout_context_t *layout,
hb_buffer_t *buffer,
unsigned int lookup_index,
hb_mask_t mask) const
{ return get_lookup (lookup_index).apply_string (layout, buffer, mask); }
inline bool sanitize (hb_sanitize_context_t *context) {
TRACE_SANITIZE ();
if (unlikely (!GSUBGPOS::sanitize (context))) return false;
OffsetTo<SubstLookupList> &list = CastR<OffsetTo<SubstLookupList> > (lookupList);
return list.sanitize (context, this);
}
public:
DEFINE_SIZE_STATIC (10);
};
/* Out-of-class implementation for methods recursing */
inline bool ExtensionSubst::apply (hb_apply_context_t *context) const
{
TRACE_APPLY ();
return get_subtable ().apply (context, get_type ());
}
inline bool ExtensionSubst::sanitize (hb_sanitize_context_t *context)
{
TRACE_SANITIZE ();
if (unlikely (!Extension::sanitize (context))) return false;
unsigned int offset = get_offset ();
if (unlikely (!offset)) return true;
return StructAtOffset<SubstLookupSubTable> (this, offset).sanitize (context, get_type ());
}
inline bool ExtensionSubst::is_reverse (void) const
{
unsigned int type = get_type ();
if (unlikely (type == SubstLookupSubTable::Extension))
return CastR<ExtensionSubst> (get_subtable()).is_reverse ();
return SubstLookup::lookup_type_is_reverse (type);
}
static inline bool substitute_lookup (hb_apply_context_t *context, unsigned int lookup_index)
{
const GSUB &gsub = *(context->layout->face->ot_layout.gsub);
const SubstLookup &l = gsub.get_lookup (lookup_index);
if (unlikely (context->nesting_level_left == 0))
return false;
if (unlikely (context->context_length < 1))
return false;
return l.apply_once (context->layout, context->buffer, context->context_length, context->nesting_level_left - 1);
}
#endif /* HB_OT_LAYOUT_GSUB_PRIVATE_HH */