harfbuzz/src/hb-ot-shaper-use-machine.rl

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/*
* Copyright © 2015 Mozilla Foundation.
* Copyright © 2015 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.
*
* Mozilla Author(s): Jonathan Kew
* Google Author(s): Behdad Esfahbod
*/
#ifndef HB_OT_SHAPER_USE_MACHINE_HH
#define HB_OT_SHAPER_USE_MACHINE_HH
#include "hb.hh"
#include "hb-ot-shaper-syllabic.hh"
/* buffer var allocations */
#define use_category() ot_shaper_var_u8_category()
#define USE(Cat) use_syllable_machine_ex_##Cat
enum use_syllable_type_t {
use_virama_terminated_cluster,
use_sakot_terminated_cluster,
use_standard_cluster,
use_number_joiner_terminated_cluster,
use_numeral_cluster,
use_symbol_cluster,
use_hieroglyph_cluster,
use_broken_cluster,
use_non_cluster,
};
%%{
machine use_syllable_machine;
alphtype unsigned char;
write exports;
write data;
}%%
%%{
# Categories used in the Universal Shaping Engine spec:
# https://docs.microsoft.com/en-us/typography/script-development/use
export O = 0; # OTHER
export B = 1; # BASE
export N = 4; # BASE_NUM
export GB = 5; # BASE_OTHER
export CGJ = 6; # CGJ
export SUB = 11; # CONS_SUB
export H = 12; # HALANT
export HN = 13; # HALANT_NUM
export ZWNJ = 14; # Zero width non-joiner
export WJ = 16; # Word joiner
export R = 18; # REPHA
export CS = 43; # CONS_WITH_STACKER
export IS = 44; # INVISIBLE_STACKER
export Sk = 48; # SAKOT
export G = 49; # HIEROGLYPH
export J = 50; # HIEROGLYPH_JOINER
export SB = 51; # HIEROGLYPH_SEGMENT_BEGIN
export SE = 52; # HIEROGLYPH_SEGMENT_END
export HVM = 53; # HALANT_OR_VOWEL_MODIFIER
export FAbv = 24; # CONS_FINAL_ABOVE
export FBlw = 25; # CONS_FINAL_BELOW
export FPst = 26; # CONS_FINAL_POST
export MAbv = 27; # CONS_MED_ABOVE
export MBlw = 28; # CONS_MED_BELOW
export MPst = 29; # CONS_MED_POST
export MPre = 30; # CONS_MED_PRE
export CMAbv = 31; # CONS_MOD_ABOVE
export CMBlw = 32; # CONS_MOD_BELOW
export VAbv = 33; # VOWEL_ABOVE / VOWEL_ABOVE_BELOW / VOWEL_ABOVE_BELOW_POST / VOWEL_ABOVE_POST
export VBlw = 34; # VOWEL_BELOW / VOWEL_BELOW_POST
export VPst = 35; # VOWEL_POST UIPC = Right
export VPre = 22; # VOWEL_PRE / VOWEL_PRE_ABOVE / VOWEL_PRE_ABOVE_POST / VOWEL_PRE_POST
export VMAbv = 37; # VOWEL_MOD_ABOVE
export VMBlw = 38; # VOWEL_MOD_BELOW
export VMPst = 39; # VOWEL_MOD_POST
export VMPre = 23; # VOWEL_MOD_PRE
export SMAbv = 41; # SYM_MOD_ABOVE
export SMBlw = 42; # SYM_MOD_BELOW
export FMAbv = 45; # CONS_FINAL_MOD UIPC = Top
export FMBlw = 46; # CONS_FINAL_MOD UIPC = Bottom
export FMPst = 47; # CONS_FINAL_MOD UIPC = Not_Applicable
h = H | HVM | IS | Sk;
consonant_modifiers = CMAbv* CMBlw* ((h B | SUB) CMAbv? CMBlw*)*;
medial_consonants = MPre? MAbv? MBlw? MPst?;
dependent_vowels = VPre* VAbv* VBlw* VPst* | H;
vowel_modifiers = HVM? VMPre* VMAbv* VMBlw* VMPst*;
final_consonants = FAbv* FBlw* FPst*;
final_modifiers = FMAbv* FMBlw* | FMPst?;
complex_syllable_start = (R | CS)? (B | GB);
complex_syllable_middle =
consonant_modifiers
medial_consonants
dependent_vowels
vowel_modifiers
(Sk B)*
;
complex_syllable_tail =
complex_syllable_middle
final_consonants
final_modifiers
;
number_joiner_terminated_cluster_tail = (HN N)* HN;
numeral_cluster_tail = (HN N)+;
symbol_cluster_tail = SMAbv+ SMBlw* | SMBlw+;
virama_terminated_cluster_tail =
consonant_modifiers
IS
;
virama_terminated_cluster =
complex_syllable_start
virama_terminated_cluster_tail
;
sakot_terminated_cluster_tail =
complex_syllable_middle
Sk
;
sakot_terminated_cluster =
complex_syllable_start
sakot_terminated_cluster_tail
;
standard_cluster =
complex_syllable_start
complex_syllable_tail
;
tail = complex_syllable_tail | sakot_terminated_cluster_tail | symbol_cluster_tail | virama_terminated_cluster_tail;
broken_cluster =
R?
(tail | number_joiner_terminated_cluster_tail | numeral_cluster_tail)
;
number_joiner_terminated_cluster = N number_joiner_terminated_cluster_tail;
numeral_cluster = N numeral_cluster_tail?;
symbol_cluster = (O | GB) tail?;
hieroglyph_cluster = SB+ | SB* G SE* (J SE* (G SE*)?)*;
other = any;
main := |*
virama_terminated_cluster ZWNJ? => { found_syllable (use_virama_terminated_cluster); };
sakot_terminated_cluster ZWNJ? => { found_syllable (use_sakot_terminated_cluster); };
standard_cluster ZWNJ? => { found_syllable (use_standard_cluster); };
number_joiner_terminated_cluster ZWNJ? => { found_syllable (use_number_joiner_terminated_cluster); };
numeral_cluster ZWNJ? => { found_syllable (use_numeral_cluster); };
symbol_cluster ZWNJ? => { found_syllable (use_symbol_cluster); };
hieroglyph_cluster ZWNJ? => { found_syllable (use_hieroglyph_cluster); };
broken_cluster ZWNJ? => { found_syllable (use_broken_cluster); buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_BROKEN_SYLLABLE; };
other => { found_syllable (use_non_cluster); };
*|;
}%%
#define found_syllable(syllable_type) \
HB_STMT_START { \
if (0) fprintf (stderr, "syllable %d..%d %s\n", (*ts).second.first, (*te).second.first, #syllable_type); \
for (unsigned i = (*ts).second.first; i < (*te).second.first; ++i) \
info[i].syllable() = (syllable_serial << 4) | syllable_type; \
syllable_serial++; \
if (unlikely (syllable_serial == 16)) syllable_serial = 1; \
} HB_STMT_END
template <typename Iter>
struct machine_index_t :
hb_iter_with_fallback_t<machine_index_t<Iter>,
typename Iter::item_t>
{
machine_index_t (const Iter& it) : it (it) {}
machine_index_t (const machine_index_t& o) : hb_iter_with_fallback_t<machine_index_t<Iter>,
typename Iter::item_t> (),
it (o.it), is_null (o.is_null) {}
static constexpr bool is_random_access_iterator = Iter::is_random_access_iterator;
static constexpr bool is_sorted_iterator = Iter::is_sorted_iterator;
typename Iter::item_t __item__ () const { return *it; }
typename Iter::item_t __item_at__ (unsigned i) const { return it[i]; }
unsigned __len__ () const { return it.len (); }
void __next__ () { ++it; }
void __forward__ (unsigned n) { it += n; }
void __prev__ () { --it; }
void __rewind__ (unsigned n) { it -= n; }
void operator = (unsigned n)
{
assert (n == 0);
is_null = true;
}
explicit operator bool () { return !is_null; }
void operator = (const machine_index_t& o)
{
is_null = o.is_null;
unsigned index = (*it).first;
unsigned n = (*o.it).first;
if (index < n) it += n - index; else if (index > n) it -= index - n;
}
bool operator == (const machine_index_t& o) const
{ return is_null ? o.is_null : !o.is_null && (*it).first == (*o.it).first; }
bool operator != (const machine_index_t& o) const { return !(*this == o); }
private:
Iter it;
bool is_null = false;
};
struct
{
template <typename Iter,
hb_requires (hb_is_iterable (Iter))>
machine_index_t<hb_iter_type<Iter>>
operator () (Iter&& it) const
{ return machine_index_t<hb_iter_type<Iter>> (hb_iter (it)); }
}
HB_FUNCOBJ (machine_index);
static bool
not_ccs_default_ignorable (const hb_glyph_info_t &i)
{ return i.use_category() != USE(CGJ); }
static inline void
find_syllables_use (hb_buffer_t *buffer)
{
hb_glyph_info_t *info = buffer->info;
auto p =
+ hb_iter (info, buffer->len)
| hb_enumerate
| hb_filter ([] (const hb_glyph_info_t &i) { return not_ccs_default_ignorable (i); },
hb_second)
| hb_filter ([&] (const hb_pair_t<unsigned, const hb_glyph_info_t &> p)
{
if (p.second.use_category() == USE(ZWNJ))
for (unsigned i = p.first + 1; i < buffer->len; ++i)
if (not_ccs_default_ignorable (info[i]))
return !_hb_glyph_info_is_unicode_mark (&info[i]);
return true;
})
| hb_enumerate
| machine_index
;
auto pe = p + p.len ();
auto eof = +pe;
auto ts = +p;
auto te = +p;
unsigned int act HB_UNUSED;
int cs;
%%{
write init;
getkey (*p).second.second.use_category();
}%%
unsigned int syllable_serial = 1;
%%{
write exec;
}%%
}
#undef found_syllable
#endif /* HB_OT_SHAPER_USE_MACHINE_HH */