harfbuzz/src/hb-ot-shape-complex-indic-machine.rl
2013-02-14 11:58:13 -05:00

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3.6 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_SHAPE_COMPLEX_INDIC_MACHINE_HH
#define HB_OT_SHAPE_COMPLEX_INDIC_MACHINE_HH
#include "hb-private.hh"
%%{
machine indic_syllable_machine;
alphtype unsigned char;
write data;
}%%
%%{
# Same order as enum indic_category_t. Not sure how to avoid duplication.
X = 0;
C = 1;
V = 2;
N = 3;
H = 4;
ZWNJ = 5;
ZWJ = 6;
M = 7;
SM = 8;
VD = 9;
A = 10;
NBSP = 11;
DOTTEDCIRCLE = 12;
RS = 13;
Coeng = 14;
Repha = 15;
Ra = 16;
CM = 17;
c = (C | Ra)CM*; # is_consonant
n = ((ZWNJ?.RS)? (N.N?)?); # is_consonant_modifier
z = ZWJ|ZWNJ; # is_joiner
h = H | Coeng; # is_halant_or_coeng
reph = (Ra H | Repha); # possible reph
cn = c.ZWJ?.n?;
forced_rakar = ZWJ H ZWJ Ra;
matra_group = z{0,3}.M.N?.(H | forced_rakar)?;
syllable_tail = (Coeng (cn|V))? (SM.ZWNJ?)? (VD VD?)?;
place_holder = NBSP | DOTTEDCIRCLE;
halant_group = (z?.h.(ZWJ.N?)?);
final_halant_group = halant_group | h.ZWNJ;
halant_or_matra_group = (final_halant_group | (h.ZWJ)? matra_group{0,4});
consonant_syllable = Repha? (cn.halant_group){0,4} cn A? halant_or_matra_group? syllable_tail;
vowel_syllable = reph? V.n? (ZWJ | (halant_group.cn){0,4} halant_or_matra_group? syllable_tail);
standalone_cluster = reph? place_holder.n? (halant_group.cn){0,4} halant_or_matra_group? syllable_tail;
broken_cluster = reph? n? (halant_group.cn){0,4} halant_or_matra_group syllable_tail;
other = any;
main := |*
consonant_syllable => { found_syllable (consonant_syllable); };
vowel_syllable => { found_syllable (vowel_syllable); };
standalone_cluster => { found_syllable (standalone_cluster); };
broken_cluster => { found_syllable (broken_cluster); };
other => { found_syllable (non_indic_cluster); };
*|;
}%%
#define found_syllable(syllable_type) \
HB_STMT_START { \
if (0) fprintf (stderr, "syllable %d..%d %s\n", last, p+1, #syllable_type); \
for (unsigned int i = last; i < p+1; i++) \
info[i].syllable() = (syllable_serial << 4) | syllable_type; \
last = p+1; \
syllable_serial++; \
if (unlikely (syllable_serial == 16)) syllable_serial = 1; \
} HB_STMT_END
static void
find_syllables (hb_buffer_t *buffer)
{
unsigned int p, pe, eof, ts HB_UNUSED, te HB_UNUSED, act HB_UNUSED;
int cs;
hb_glyph_info_t *info = buffer->info;
%%{
write init;
getkey info[p].indic_category();
}%%
p = 0;
pe = eof = buffer->len;
unsigned int last = 0;
unsigned int syllable_serial = 1;
%%{
write exec;
}%%
}
#endif /* HB_OT_SHAPE_COMPLEX_INDIC_MACHINE_HH */