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

152 lines
4.2 KiB
Ragel

/*
* Copyright © 2011,2012 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_SHAPER_INDIC_MACHINE_HH
#define HB_OT_SHAPER_INDIC_MACHINE_HH
#include "hb.hh"
#include "hb-ot-layout.hh"
#include "hb-ot-shaper-indic.hh"
/* buffer var allocations */
#define indic_category() ot_shaper_var_u8_category() /* indic_category_t */
#define indic_position() ot_shaper_var_u8_auxiliary() /* indic_position_t */
using indic_category_t = unsigned;
using indic_position_t = ot_position_t;
#define I_Cat(Cat) indic_syllable_machine_ex_##Cat
enum indic_syllable_type_t {
indic_consonant_syllable,
indic_vowel_syllable,
indic_standalone_cluster,
indic_symbol_cluster,
indic_broken_cluster,
indic_non_indic_cluster,
};
%%{
machine indic_syllable_machine;
alphtype unsigned char;
write exports;
write data;
}%%
%%{
export X = 0;
export C = 1;
export V = 2;
export N = 3;
export H = 4;
export ZWNJ = 5;
export ZWJ = 6;
export M = 7;
export SM = 8;
export A = 9;
export VD = 9;
export PLACEHOLDER = 10;
export DOTTEDCIRCLE = 11;
export RS = 12;
export MPst = 13;
export Repha = 14;
export Ra = 15;
export CM = 16;
export Symbol= 17;
export CS = 18;
c = (C | Ra); # is_consonant
n = ((ZWNJ?.RS)? (N.N?)?); # is_consonant_modifier
z = ZWJ|ZWNJ; # is_joiner
reph = (Ra H | Repha); # possible reph
cn = c.ZWJ?.n?;
symbol = Symbol.N?;
matra_group = z*.(M | SM? MPst).N?.H?;
syllable_tail = (z?.SM.SM?.ZWNJ?)? (A | VD)*;
halant_group = (z?.H.(ZWJ.N?)?);
final_halant_group = halant_group | H.ZWNJ;
medial_group = CM?;
halant_or_matra_group = (final_halant_group | matra_group*);
complex_syllable_tail = (halant_group.cn)* medial_group halant_or_matra_group syllable_tail;
consonant_syllable = (Repha|CS)? cn complex_syllable_tail;
vowel_syllable = reph? V.n? (ZWJ | complex_syllable_tail);
standalone_cluster = ((Repha|CS)? PLACEHOLDER | reph? DOTTEDCIRCLE).n? complex_syllable_tail;
symbol_cluster = symbol syllable_tail;
broken_cluster = reph? n? complex_syllable_tail;
other = any;
main := |*
consonant_syllable => { found_syllable (indic_consonant_syllable); };
vowel_syllable => { found_syllable (indic_vowel_syllable); };
standalone_cluster => { found_syllable (indic_standalone_cluster); };
symbol_cluster => { found_syllable (indic_symbol_cluster); };
broken_cluster => { found_syllable (indic_broken_cluster); buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_BROKEN_SYLLABLE; };
other => { found_syllable (indic_non_indic_cluster); };
*|;
}%%
#define found_syllable(syllable_type) \
HB_STMT_START { \
if (0) fprintf (stderr, "syllable %u..%u %s\n", ts, te, #syllable_type); \
for (unsigned int i = ts; i < te; i++) \
info[i].syllable() = (syllable_serial << 4) | syllable_type; \
syllable_serial++; \
if (syllable_serial == 16) syllable_serial = 1; \
} HB_STMT_END
inline void
find_syllables_indic (hb_buffer_t *buffer)
{
unsigned int p, pe, eof, ts, te, act;
int cs;
hb_glyph_info_t *info = buffer->info;
%%{
write init;
getkey info[p].indic_category();
}%%
p = 0;
pe = eof = buffer->len;
unsigned int syllable_serial = 1;
%%{
write exec;
}%%
}
#undef found_syllable
#endif /* HB_OT_SHAPER_INDIC_MACHINE_HH */