harfbuzz/src/hb-ot-shaper-hebrew.cc

212 lines
5.7 KiB
C++

/*
* Copyright © 2010,2012 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
*/
#include "hb.hh"
#ifndef HB_NO_OT_SHAPE
#include "hb-ot-shaper.hh"
static bool
compose_hebrew (const hb_ot_shape_normalize_context_t *c,
hb_codepoint_t a,
hb_codepoint_t b,
hb_codepoint_t *ab)
{
/* Hebrew presentation-form shaping.
* https://bugzilla.mozilla.org/show_bug.cgi?id=728866
* Hebrew presentation forms with dagesh, for characters U+05D0..05EA;
* Note that some letters do not have a dagesh presForm encoded.
*/
static const hb_codepoint_t sDageshForms[0x05EAu - 0x05D0u + 1] = {
0xFB30u, /* ALEF */
0xFB31u, /* BET */
0xFB32u, /* GIMEL */
0xFB33u, /* DALET */
0xFB34u, /* HE */
0xFB35u, /* VAV */
0xFB36u, /* ZAYIN */
0x0000u, /* HET */
0xFB38u, /* TET */
0xFB39u, /* YOD */
0xFB3Au, /* FINAL KAF */
0xFB3Bu, /* KAF */
0xFB3Cu, /* LAMED */
0x0000u, /* FINAL MEM */
0xFB3Eu, /* MEM */
0x0000u, /* FINAL NUN */
0xFB40u, /* NUN */
0xFB41u, /* SAMEKH */
0x0000u, /* AYIN */
0xFB43u, /* FINAL PE */
0xFB44u, /* PE */
0x0000u, /* FINAL TSADI */
0xFB46u, /* TSADI */
0xFB47u, /* QOF */
0xFB48u, /* RESH */
0xFB49u, /* SHIN */
0xFB4Au /* TAV */
};
bool found = (bool) c->unicode->compose (a, b, ab);
#ifdef HB_NO_OT_SHAPER_HEBREW_FALLBACK
return found;
#endif
if (!found && !c->plan->has_gpos_mark)
{
/* Special-case Hebrew presentation forms that are excluded from
* standard normalization, but wanted for old fonts. */
switch (b) {
case 0x05B4u: /* HIRIQ */
if (a == 0x05D9u) { /* YOD */
*ab = 0xFB1Du;
found = true;
}
break;
case 0x05B7u: /* PATAH */
if (a == 0x05F2u) { /* YIDDISH YOD YOD */
*ab = 0xFB1Fu;
found = true;
} else if (a == 0x05D0u) { /* ALEF */
*ab = 0xFB2Eu;
found = true;
}
break;
case 0x05B8u: /* QAMATS */
if (a == 0x05D0u) { /* ALEF */
*ab = 0xFB2Fu;
found = true;
}
break;
case 0x05B9u: /* HOLAM */
if (a == 0x05D5u) { /* VAV */
*ab = 0xFB4Bu;
found = true;
}
break;
case 0x05BCu: /* DAGESH */
if (a >= 0x05D0u && a <= 0x05EAu) {
*ab = sDageshForms[a - 0x05D0u];
found = (*ab != 0);
} else if (a == 0xFB2Au) { /* SHIN WITH SHIN DOT */
*ab = 0xFB2Cu;
found = true;
} else if (a == 0xFB2Bu) { /* SHIN WITH SIN DOT */
*ab = 0xFB2Du;
found = true;
}
break;
case 0x05BFu: /* RAFE */
switch (a) {
case 0x05D1u: /* BET */
*ab = 0xFB4Cu;
found = true;
break;
case 0x05DBu: /* KAF */
*ab = 0xFB4Du;
found = true;
break;
case 0x05E4u: /* PE */
*ab = 0xFB4Eu;
found = true;
break;
}
break;
case 0x05C1u: /* SHIN DOT */
if (a == 0x05E9u) { /* SHIN */
*ab = 0xFB2Au;
found = true;
} else if (a == 0xFB49u) { /* SHIN WITH DAGESH */
*ab = 0xFB2Cu;
found = true;
}
break;
case 0x05C2u: /* SIN DOT */
if (a == 0x05E9u) { /* SHIN */
*ab = 0xFB2Bu;
found = true;
} else if (a == 0xFB49u) { /* SHIN WITH DAGESH */
*ab = 0xFB2Du;
found = true;
}
break;
}
}
return found;
}
static void
reorder_marks_hebrew (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_buffer_t *buffer,
unsigned int start,
unsigned int end)
{
hb_glyph_info_t *info = buffer->info;
for (unsigned i = start + 2; i < end; i++)
{
unsigned c0 = info_cc (info[i - 2]);
unsigned c1 = info_cc (info[i - 1]);
unsigned c2 = info_cc (info[i - 0]);
if ((c0 == HB_MODIFIED_COMBINING_CLASS_CCC17 || c0 == HB_MODIFIED_COMBINING_CLASS_CCC18) /* patach or qamats */ &&
(c1 == HB_MODIFIED_COMBINING_CLASS_CCC10 || c1 == HB_MODIFIED_COMBINING_CLASS_CCC14) /* sheva or hiriq */ &&
(c2 == HB_MODIFIED_COMBINING_CLASS_CCC22 || c2 == HB_UNICODE_COMBINING_CLASS_BELOW) /* meteg or below */)
{
buffer->merge_clusters (i - 1, i + 1);
hb_swap (info[i - 1], info[i]);
break;
}
}
}
const hb_ot_shaper_t _hb_ot_shaper_hebrew =
{
nullptr, /* collect_features */
nullptr, /* override_features */
nullptr, /* data_create */
nullptr, /* data_destroy */
nullptr, /* preprocess_text */
nullptr, /* postprocess_glyphs */
nullptr, /* decompose */
compose_hebrew,
nullptr, /* setup_masks */
reorder_marks_hebrew,
HB_TAG ('h','e','b','r'), /* gpos_tag. https://github.com/harfbuzz/harfbuzz/issues/347#issuecomment-267838368 */
HB_OT_SHAPE_NORMALIZATION_MODE_DEFAULT,
HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE,
true, /* fallback_position */
};
#endif