harfbuzz/src/hb-ot-shape-complex-khmer.hh

125 lines
3.3 KiB
C++

/*
* Copyright © 2018 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_KHMER_HH
#define HB_OT_SHAPE_COMPLEX_KHMER_HH
#include "hb.hh"
#include "hb-ot-shape-complex-indic.hh"
/* buffer var allocations */
#define khmer_category() indic_category() /* khmer_category_t */
#define khmer_position() indic_position() /* khmer_position_t */
typedef indic_category_t khmer_category_t;
typedef indic_position_t khmer_position_t;
static inline khmer_position_t
matra_position_khmer (khmer_position_t side)
{
switch ((int) side)
{
case POS_PRE_C:
return POS_PRE_M;
case POS_POST_C:
case POS_ABOVE_C:
case POS_BELOW_C:
return POS_AFTER_POST;
default:
return side;
};
}
static inline bool
is_consonant_or_vowel (const hb_glyph_info_t &info)
{
return is_one_of (info, CONSONANT_FLAGS | FLAG (OT_V));
}
static inline bool
is_coeng (const hb_glyph_info_t &info)
{
return is_one_of (info, FLAG (OT_Coeng));
}
static inline void
set_khmer_properties (hb_glyph_info_t &info)
{
hb_codepoint_t u = info.codepoint;
unsigned int type = hb_indic_get_categories (u);
khmer_category_t cat = (khmer_category_t) (type & 0x7Fu);
khmer_position_t pos = (khmer_position_t) (type >> 8);
/*
* Re-assign category
*/
if (unlikely (u == 0x17C6u)) cat = OT_N; /* Khmer Bindu doesn't like to be repositioned. */
else if (unlikely (hb_in_range<hb_codepoint_t> (u, 0x17CDu, 0x17D1u) ||
u == 0x17CBu || u == 0x17D3u || u == 0x17DDu)) /* Khmer Various signs */
{
/* These can occur mid-syllable (eg. before matras), even though Unicode marks them as Syllable_Modifier.
* https://github.com/roozbehp/unicode-data/issues/5 */
cat = OT_M;
pos = POS_ABOVE_C;
}
else if (unlikely (hb_in_range<hb_codepoint_t> (u, 0x2010u, 0x2011u))) cat = OT_PLACEHOLDER;
else if (unlikely (u == 0x25CCu)) cat = OT_DOTTEDCIRCLE;
/*
* Re-assign position.
*/
if ((FLAG_UNSAFE (cat) & CONSONANT_FLAGS))
{
pos = POS_BASE_C;
if (u == 0x179Au)
cat = OT_Ra;
}
else if (cat == OT_M)
{
pos = matra_position_khmer (pos);
}
else if ((FLAG_UNSAFE (cat) & (FLAG (OT_SM) | FLAG (OT_A) | FLAG (OT_Symbol))))
{
pos = POS_SMVD;
}
info.khmer_category() = cat;
info.khmer_position() = pos;
}
#endif /* HB_OT_SHAPE_COMPLEX_KHMER_HH */