harfbuzz/src/hb-ot-shape-complex-myanmar.cc

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/*
* Copyright © 2011,2012,2013 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-ot-shape-complex-indic-private.hh"
/* buffer var allocations */
#define myanmar_category() complex_var_u8_0() /* myanmar_category_t */
#define myanmar_position() complex_var_u8_1() /* myanmar_position_t */
/*
* Myanmar shaper.
*/
static const hb_tag_t
myanmar_features[] =
{
/*
* Basic features.
* These features are applied in order, one at a time, after initial_reordering.
*/
HB_TAG('r','p','h','f'),
HB_TAG('p','r','e','f'),
HB_TAG('b','l','w','f'),
HB_TAG('p','s','t','f'),
/*
* Other features.
* These features are applied all at once, after final_reordering.
*/
HB_TAG('p','r','e','s'),
HB_TAG('a','b','v','s'),
HB_TAG('b','l','w','s'),
HB_TAG('p','s','t','s'),
/* Positioning features, though we don't care about the types. */
HB_TAG('d','i','s','t'),
};
/*
* Must be in the same order as the myanmar_features array.
*/
enum {
_RPHF,
_PREF,
_BLWF,
_PSTF,
_PRES,
_ABVS,
_BLWS,
_PSTS,
_DIST,
MYANMAR_NUM_FEATURES,
MYANMAR_BASIC_FEATURES = _PRES /* Don't forget to update this! */
};
static void
setup_syllables (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer);
static void
initial_reordering (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer);
static void
final_reordering (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer);
static void
collect_features_myanmar (hb_ot_shape_planner_t *plan)
{
hb_ot_map_builder_t *map = &plan->map;
/* Do this before any lookups have been applied. */
map->add_gsub_pause (setup_syllables);
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map->add_global_bool_feature (HB_TAG('l','o','c','l'));
/* The Indic specs do not require ccmp, but we apply it here since if
* there is a use of it, it's typically at the beginning. */
2013-02-14 17:05:56 +01:00
map->add_global_bool_feature (HB_TAG('c','c','m','p'));
unsigned int i = 0;
map->add_gsub_pause (initial_reordering);
for (; i < MYANMAR_BASIC_FEATURES; i++) {
[Indic-like] Disable automatic joiner handling for basic shaping features Not for Arabic, but for Indic-like scripts. ZWJ/ZWNJ have special meanings in those scripts, so let font lookups take full control. This undoes the regression caused by automatic-joiners handling introduced two commits ago. We only disable automatic joiner handling for the "basic shaping features" of Indic, Myanmar, and SEAsian shapers. The "presentation forms" and other features are still applied with automatic-joiner handling. This change also changes the test suite failure statistics, such that a few scripts show more "failures". The most affected is Kannada. However, upon inspection, we believe that in most, if not all, of the new failures, we are producing results superior to Uniscribe. Hard to count those! Here's an example of what is fixed by the recent joiner-handling changes: https://bugs.freedesktop.org/show_bug.cgi?id=58714 New numbers, for future reference: BENGALI: 353892 out of 354188 tests passed. 296 failed (0.0835714%) DEVANAGARI: 707336 out of 707394 tests passed. 58 failed (0.00819911%) GUJARATI: 366262 out of 366457 tests passed. 195 failed (0.0532122%) GURMUKHI: 60706 out of 60747 tests passed. 41 failed (0.067493%) KANNADA: 950680 out of 951913 tests passed. 1233 failed (0.129529%) KHMER: 299074 out of 299124 tests passed. 50 failed (0.0167155%) LAO: 53611 out of 53644 tests passed. 33 failed (0.0615167%) MALAYALAM: 1047983 out of 1048334 tests passed. 351 failed (0.0334817%) ORIYA: 42320 out of 42329 tests passed. 9 failed (0.021262%) SINHALA: 271539 out of 271847 tests passed. 308 failed (0.113299%) TAMIL: 1091753 out of 1091754 tests passed. 1 failed (9.15957e-05%) TELUGU: 970555 out of 970573 tests passed. 18 failed (0.00185457%) TIBETAN: 208469 out of 208469 tests passed. 0 failed (0%)
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map->add_feature (myanmar_features[i], 1, F_GLOBAL | F_MANUAL_JOINERS);
map->add_gsub_pause (NULL);
}
map->add_gsub_pause (final_reordering);
for (; i < MYANMAR_NUM_FEATURES; i++) {
[Indic-like] Disable automatic joiner handling for basic shaping features Not for Arabic, but for Indic-like scripts. ZWJ/ZWNJ have special meanings in those scripts, so let font lookups take full control. This undoes the regression caused by automatic-joiners handling introduced two commits ago. We only disable automatic joiner handling for the "basic shaping features" of Indic, Myanmar, and SEAsian shapers. The "presentation forms" and other features are still applied with automatic-joiner handling. This change also changes the test suite failure statistics, such that a few scripts show more "failures". The most affected is Kannada. However, upon inspection, we believe that in most, if not all, of the new failures, we are producing results superior to Uniscribe. Hard to count those! Here's an example of what is fixed by the recent joiner-handling changes: https://bugs.freedesktop.org/show_bug.cgi?id=58714 New numbers, for future reference: BENGALI: 353892 out of 354188 tests passed. 296 failed (0.0835714%) DEVANAGARI: 707336 out of 707394 tests passed. 58 failed (0.00819911%) GUJARATI: 366262 out of 366457 tests passed. 195 failed (0.0532122%) GURMUKHI: 60706 out of 60747 tests passed. 41 failed (0.067493%) KANNADA: 950680 out of 951913 tests passed. 1233 failed (0.129529%) KHMER: 299074 out of 299124 tests passed. 50 failed (0.0167155%) LAO: 53611 out of 53644 tests passed. 33 failed (0.0615167%) MALAYALAM: 1047983 out of 1048334 tests passed. 351 failed (0.0334817%) ORIYA: 42320 out of 42329 tests passed. 9 failed (0.021262%) SINHALA: 271539 out of 271847 tests passed. 308 failed (0.113299%) TAMIL: 1091753 out of 1091754 tests passed. 1 failed (9.15957e-05%) TELUGU: 970555 out of 970573 tests passed. 18 failed (0.00185457%) TIBETAN: 208469 out of 208469 tests passed. 0 failed (0%)
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map->add_feature (myanmar_features[i], 1, F_GLOBAL);
}
}
static void
override_features_myanmar (hb_ot_shape_planner_t *plan)
{
plan->map.add_feature (HB_TAG('l','i','g','a'), 0, F_GLOBAL);
/*
* Note:
*
* Spec says 'mark' is used, and the mmrtext.ttf font from
* Windows 8 has lookups for it. But testing suggests that
* Windows 8 Uniscribe is NOT applying it. It *is* applying
* 'mkmk' however.
*/
if (hb_options ().uniscribe_bug_compatible)
plan->map.add_feature (HB_TAG('m','a','r','k'), 0, F_GLOBAL);
}
enum syllable_type_t {
consonant_syllable,
broken_cluster,
non_myanmar_cluster,
};
#include "hb-ot-shape-complex-myanmar-machine.hh"
/* Note: This enum is duplicated in the -machine.rl source file.
* Not sure how to avoid duplication. */
enum myanmar_category_t {
OT_As = 18, /* Asat */
OT_D = 19, /* Digits except zero */
OT_D0 = 20, /* Digit zero */
OT_DB = OT_N, /* Dot below */
OT_GB = OT_DOTTEDCIRCLE,
OT_MH = 21, /* Various consonant medial types */
OT_MR = 22, /* Various consonant medial types */
OT_MW = 23, /* Various consonant medial types */
OT_MY = 24, /* Various consonant medial types */
OT_PT = 25, /* Pwo and other tones */
OT_VAbv = 26,
OT_VBlw = 27,
OT_VPre = 28,
OT_VPst = 29,
OT_VS = 30 /* Variation selectors */
};
static inline bool
is_one_of (const hb_glyph_info_t &info, unsigned int flags)
{
/* If it ligated, all bets are off. */
if (is_a_ligature (info)) return false;
return !!(FLAG (info.myanmar_category()) & flags);
}
/* Note:
*
* We treat Vowels and placeholders as if they were consonants. This is safe because Vowels
* cannot happen in a consonant syllable. The plus side however is, we can call the
* consonant syllable logic from the vowel syllable function and get it all right! */
#define CONSONANT_FLAGS (FLAG (OT_C) | FLAG (OT_CM) | FLAG (OT_Ra) | FLAG (OT_V) | FLAG (OT_NBSP) | FLAG (OT_GB))
static inline bool
is_consonant (const hb_glyph_info_t &info)
{
return is_one_of (info, CONSONANT_FLAGS);
}
static inline void
set_myanmar_properties (hb_glyph_info_t &info)
{
hb_codepoint_t u = info.codepoint;
unsigned int type = hb_indic_get_categories (u);
indic_category_t cat = (indic_category_t) (type & 0x7F);
indic_position_t pos = (indic_position_t) (type >> 8);
/* Myanmar
* http://www.microsoft.com/typography/OpenTypeDev/myanmar/intro.htm#analyze
*/
if (unlikely (hb_in_range<hb_codepoint_t> (u, 0xFE00, 0xFE0F)))
cat = (indic_category_t) OT_VS;
else if (unlikely (u == 0x200C)) cat = (indic_category_t) OT_ZWNJ;
else if (unlikely (u == 0x200D)) cat = (indic_category_t) OT_ZWJ;
switch (u)
{
case 0x002D: case 0x00A0: case 0x00D7: case 0x2012:
case 0x2013: case 0x2014: case 0x2015: case 0x2022:
case 0x25CC: case 0x25FB: case 0x25FC: case 0x25FD:
case 0x25FE:
cat = (indic_category_t) OT_GB;
break;
case 0x1004: case 0x101B: case 0x105A:
cat = (indic_category_t) OT_Ra;
break;
case 0x1032: case 0x1036:
cat = (indic_category_t) OT_A;
break;
case 0x103A:
cat = (indic_category_t) OT_As;
break;
case 0x1041: case 0x1042: case 0x1043: case 0x1044:
case 0x1045: case 0x1046: case 0x1047: case 0x1048:
case 0x1049: case 0x1090: case 0x1091: case 0x1092:
case 0x1093: case 0x1094: case 0x1095: case 0x1096:
case 0x1097: case 0x1098: case 0x1099:
cat = (indic_category_t) OT_D;
break;
case 0x1040:
cat = (indic_category_t) OT_D; /* XXX The spec says D0, but Uniscribe doesn't seem to do. */
break;
case 0x103E: case 0x1060:
cat = (indic_category_t) OT_MH;
break;
case 0x103C:
cat = (indic_category_t) OT_MR;
break;
case 0x103D: case 0x1082:
cat = (indic_category_t) OT_MW;
break;
case 0x103B: case 0x105E: case 0x105F:
cat = (indic_category_t) OT_MY;
break;
case 0x1063: case 0x1064: case 0x1069: case 0x106A:
case 0x106B: case 0x106C: case 0x106D: case 0xAA7B:
cat = (indic_category_t) OT_PT;
break;
case 0x1038: case 0x1087: case 0x1088: case 0x1089:
case 0x108A: case 0x108B: case 0x108C: case 0x108D:
case 0x108F: case 0x109A: case 0x109B: case 0x109C:
cat = (indic_category_t) OT_SM;
break;
}
if (cat == OT_M)
{
switch ((int) pos)
{
case POS_PRE_C: cat = (indic_category_t) OT_VPre;
pos = POS_PRE_M; break;
case POS_ABOVE_C: cat = (indic_category_t) OT_VAbv; break;
case POS_BELOW_C: cat = (indic_category_t) OT_VBlw; break;
case POS_POST_C: cat = (indic_category_t) OT_VPst; break;
}
}
info.myanmar_category() = (myanmar_category_t) cat;
info.myanmar_position() = pos;
}
static void
setup_masks_myanmar (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_buffer_t *buffer,
hb_font_t *font HB_UNUSED)
{
HB_BUFFER_ALLOCATE_VAR (buffer, myanmar_category);
HB_BUFFER_ALLOCATE_VAR (buffer, myanmar_position);
/* We cannot setup masks here. We save information about characters
* and setup masks later on in a pause-callback. */
unsigned int count = buffer->len;
for (unsigned int i = 0; i < count; i++)
set_myanmar_properties (buffer->info[i]);
}
static void
setup_syllables (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_font_t *font HB_UNUSED,
hb_buffer_t *buffer)
{
find_syllables (buffer);
}
static int
compare_myanmar_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
{
int a = pa->myanmar_position();
int b = pb->myanmar_position();
return a < b ? -1 : a == b ? 0 : +1;
}
/* Rules from:
* http://www.microsoft.com/typography/OpenTypeDev/myanmar/intro.htm */
static void
initial_reordering_consonant_syllable (const hb_ot_shape_plan_t *plan,
hb_face_t *face,
hb_buffer_t *buffer,
unsigned int start, unsigned int end)
{
hb_glyph_info_t *info = buffer->info;
unsigned int base = end;
bool has_reph = false;
{
unsigned int limit = start;
if (start + 3 <= end &&
info[start ].myanmar_category() == OT_Ra &&
info[start+1].myanmar_category() == OT_As &&
info[start+2].myanmar_category() == OT_H)
{
limit += 3;
base = start;
has_reph = true;
}
{
if (!has_reph)
base = limit;
for (unsigned int i = limit; i < end; i++)
if (is_consonant (info[i]))
{
base = i;
break;
}
}
}
/* Reorder! */
{
unsigned int i = start;
for (; i < start + (has_reph ? 3 : 0); i++)
info[i].myanmar_position() = POS_AFTER_MAIN;
for (; i < base; i++)
info[i].myanmar_position() = POS_PRE_C;
if (i < end)
{
info[i].myanmar_position() = POS_BASE_C;
i++;
}
indic_position_t pos = POS_AFTER_MAIN;
/* The following loop may be ugly, but it implements all of
* Myanmar reordering! */
for (; i < end; i++)
{
if (info[i].myanmar_category() == OT_MR) /* Pre-base reordering */
{
info[i].myanmar_position() = POS_PRE_C;
continue;
}
if (info[i].myanmar_position() < POS_BASE_C) /* Left matra */
{
continue;
}
if (pos == POS_AFTER_MAIN && info[i].myanmar_category() == OT_VBlw)
{
pos = POS_BELOW_C;
info[i].myanmar_position() = pos;
continue;
}
if (pos == POS_BELOW_C && info[i].myanmar_category() == OT_A)
{
info[i].myanmar_position() = POS_BEFORE_SUB;
continue;
}
if (pos == POS_BELOW_C && info[i].myanmar_category() == OT_VBlw)
{
info[i].myanmar_position() = pos;
continue;
}
if (pos == POS_BELOW_C && info[i].myanmar_category() != OT_A)
{
pos = POS_AFTER_SUB;
info[i].myanmar_position() = pos;
continue;
}
info[i].myanmar_position() = pos;
}
}
buffer->merge_clusters (start, end);
/* Sit tight, rock 'n roll! */
hb_bubble_sort (info + start, end - start, compare_myanmar_order);
}
static void
initial_reordering_broken_cluster (const hb_ot_shape_plan_t *plan,
hb_face_t *face,
hb_buffer_t *buffer,
unsigned int start, unsigned int end)
{
/* We already inserted dotted-circles, so just call the consonant_syllable. */
initial_reordering_consonant_syllable (plan, face, buffer, start, end);
}
static void
initial_reordering_non_myanmar_cluster (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_face_t *face HB_UNUSED,
hb_buffer_t *buffer HB_UNUSED,
unsigned int start HB_UNUSED, unsigned int end HB_UNUSED)
{
/* Nothing to do right now. If we ever switch to using the output
* buffer in the reordering process, we'd need to next_glyph() here. */
}
static void
initial_reordering_syllable (const hb_ot_shape_plan_t *plan,
hb_face_t *face,
hb_buffer_t *buffer,
unsigned int start, unsigned int end)
{
syllable_type_t syllable_type = (syllable_type_t) (buffer->info[start].syllable() & 0x0F);
switch (syllable_type) {
case consonant_syllable: initial_reordering_consonant_syllable (plan, face, buffer, start, end); return;
case broken_cluster: initial_reordering_broken_cluster (plan, face, buffer, start, end); return;
case non_myanmar_cluster: initial_reordering_non_myanmar_cluster (plan, face, buffer, start, end); return;
}
}
static inline void
insert_dotted_circles (const hb_ot_shape_plan_t *plan HB_UNUSED,
hb_font_t *font,
hb_buffer_t *buffer)
{
/* Note: This loop is extra overhead, but should not be measurable. */
bool has_broken_syllables = false;
unsigned int count = buffer->len;
for (unsigned int i = 0; i < count; i++)
if ((buffer->info[i].syllable() & 0x0F) == broken_cluster) {
has_broken_syllables = true;
break;
}
if (likely (!has_broken_syllables))
return;
hb_codepoint_t dottedcircle_glyph;
if (!font->get_glyph (0x25CC, 0, &dottedcircle_glyph))
return;
hb_glyph_info_t dottedcircle = {0};
dottedcircle.codepoint = 0x25CC;
set_myanmar_properties (dottedcircle);
dottedcircle.codepoint = dottedcircle_glyph;
buffer->clear_output ();
buffer->idx = 0;
unsigned int last_syllable = 0;
while (buffer->idx < buffer->len)
{
unsigned int syllable = buffer->cur().syllable();
syllable_type_t syllable_type = (syllable_type_t) (syllable & 0x0F);
if (unlikely (last_syllable != syllable && syllable_type == broken_cluster))
{
last_syllable = syllable;
hb_glyph_info_t info = dottedcircle;
info.cluster = buffer->cur().cluster;
info.mask = buffer->cur().mask;
info.syllable() = buffer->cur().syllable();
buffer->output_info (info);
}
else
buffer->next_glyph ();
}
buffer->swap_buffers ();
}
static void
initial_reordering (const hb_ot_shape_plan_t *plan,
hb_font_t *font,
hb_buffer_t *buffer)
{
insert_dotted_circles (plan, font, buffer);
hb_glyph_info_t *info = buffer->info;
unsigned int count = buffer->len;
if (unlikely (!count)) return;
unsigned int last = 0;
unsigned int last_syllable = info[0].syllable();
for (unsigned int i = 1; i < count; i++)
if (last_syllable != info[i].syllable()) {
initial_reordering_syllable (plan, font->face, buffer, last, i);
last = i;
last_syllable = info[last].syllable();
}
initial_reordering_syllable (plan, font->face, buffer, last, count);
}
static void
final_reordering (const hb_ot_shape_plan_t *plan,
hb_font_t *font HB_UNUSED,
hb_buffer_t *buffer)
{
hb_glyph_info_t *info = buffer->info;
unsigned int count = buffer->len;
/* Zero syllables now... */
for (unsigned int i = 0; i < count; i++)
info[i].syllable() = 0;
HB_BUFFER_DEALLOCATE_VAR (buffer, myanmar_category);
HB_BUFFER_DEALLOCATE_VAR (buffer, myanmar_position);
}
static hb_ot_shape_normalization_mode_t
normalization_preference_myanmar (const hb_segment_properties_t *props HB_UNUSED)
{
return HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT;
}
const hb_ot_complex_shaper_t _hb_ot_complex_shaper_myanmar =
{
"myanmar",
collect_features_myanmar,
override_features_myanmar,
NULL, /* data_create */
NULL, /* data_destroy */
NULL, /* preprocess_text */
normalization_preference_myanmar,
NULL, /* decompose */
NULL, /* compose */
setup_masks_myanmar,
HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF,
false, /* fallback_position */
};