diff options
Diffstat (limited to 'src/3rdparty/harfbuzz-ng/src/hb-ot-shape-complex-arabic.cc')
| -rw-r--r-- | src/3rdparty/harfbuzz-ng/src/hb-ot-shape-complex-arabic.cc | 718 |
1 files changed, 0 insertions, 718 deletions
diff --git a/src/3rdparty/harfbuzz-ng/src/hb-ot-shape-complex-arabic.cc b/src/3rdparty/harfbuzz-ng/src/hb-ot-shape-complex-arabic.cc deleted file mode 100644 index f92e6378a1..0000000000 --- a/src/3rdparty/harfbuzz-ng/src/hb-ot-shape-complex-arabic.cc +++ /dev/null @@ -1,718 +0,0 @@ -/* - * 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-shape-complex-arabic.hh" -#include "hb-ot-shape.hh" - - -/* buffer var allocations */ -#define arabic_shaping_action() complex_var_u8_0() /* arabic shaping action */ - -#define HB_BUFFER_SCRATCH_FLAG_ARABIC_HAS_STCH HB_BUFFER_SCRATCH_FLAG_COMPLEX0 - -/* See: - * https://github.com/harfbuzz/harfbuzz/commit/6e6f82b6f3dde0fc6c3c7d991d9ec6cfff57823d#commitcomment-14248516 */ -#define HB_ARABIC_GENERAL_CATEGORY_IS_WORD(gen_cat) \ - (FLAG_UNSAFE (gen_cat) & \ - (FLAG (HB_UNICODE_GENERAL_CATEGORY_UNASSIGNED) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_PRIVATE_USE) | \ - /*FLAG (HB_UNICODE_GENERAL_CATEGORY_LOWERCASE_LETTER) |*/ \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_MODIFIER_LETTER) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_OTHER_LETTER) | \ - /*FLAG (HB_UNICODE_GENERAL_CATEGORY_TITLECASE_LETTER) |*/ \ - /*FLAG (HB_UNICODE_GENERAL_CATEGORY_UPPERCASE_LETTER) |*/ \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_SPACING_MARK) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_ENCLOSING_MARK) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_DECIMAL_NUMBER) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_LETTER_NUMBER) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_OTHER_NUMBER) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_CURRENCY_SYMBOL) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_MODIFIER_SYMBOL) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_MATH_SYMBOL) | \ - FLAG (HB_UNICODE_GENERAL_CATEGORY_OTHER_SYMBOL))) - - -/* - * Joining types: - */ - -/* - * Bits used in the joining tables - */ -enum hb_arabic_joining_type_t { - JOINING_TYPE_U = 0, - JOINING_TYPE_L = 1, - JOINING_TYPE_R = 2, - JOINING_TYPE_D = 3, - JOINING_TYPE_C = JOINING_TYPE_D, - JOINING_GROUP_ALAPH = 4, - JOINING_GROUP_DALATH_RISH = 5, - NUM_STATE_MACHINE_COLS = 6, - - JOINING_TYPE_T = 7, - JOINING_TYPE_X = 8 /* means: use general-category to choose between U or T. */ -}; - -#include "hb-ot-shape-complex-arabic-table.hh" - -static unsigned int get_joining_type (hb_codepoint_t u, hb_unicode_general_category_t gen_cat) -{ - unsigned int j_type = joining_type(u); - if (likely (j_type != JOINING_TYPE_X)) - return j_type; - - return (FLAG_UNSAFE(gen_cat) & - (FLAG(HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) | - FLAG(HB_UNICODE_GENERAL_CATEGORY_ENCLOSING_MARK) | - FLAG(HB_UNICODE_GENERAL_CATEGORY_FORMAT)) - ) ? JOINING_TYPE_T : JOINING_TYPE_U; -} - -#define FEATURE_IS_SYRIAC(tag) hb_in_range<unsigned char> ((unsigned char) (tag), '2', '3') - -static const hb_tag_t arabic_features[] = -{ - HB_TAG('i','s','o','l'), - HB_TAG('f','i','n','a'), - HB_TAG('f','i','n','2'), - HB_TAG('f','i','n','3'), - HB_TAG('m','e','d','i'), - HB_TAG('m','e','d','2'), - HB_TAG('i','n','i','t'), - HB_TAG_NONE -}; - - -/* Same order as the feature array */ -enum arabic_action_t { - ISOL, - FINA, - FIN2, - FIN3, - MEDI, - MED2, - INIT, - - NONE, - - ARABIC_NUM_FEATURES = NONE, - - /* We abuse the same byte for other things... */ - STCH_FIXED, - STCH_REPEATING, -}; - -static const struct arabic_state_table_entry { - uint8_t prev_action; - uint8_t curr_action; - uint16_t next_state; -} arabic_state_table[][NUM_STATE_MACHINE_COLS] = -{ - /* jt_U, jt_L, jt_R, jt_D, jg_ALAPH, jg_DALATH_RISH */ - - /* State 0: prev was U, not willing to join. */ - { {NONE,NONE,0}, {NONE,ISOL,2}, {NONE,ISOL,1}, {NONE,ISOL,2}, {NONE,ISOL,1}, {NONE,ISOL,6}, }, - - /* State 1: prev was R or ISOL/ALAPH, not willing to join. */ - { {NONE,NONE,0}, {NONE,ISOL,2}, {NONE,ISOL,1}, {NONE,ISOL,2}, {NONE,FIN2,5}, {NONE,ISOL,6}, }, - - /* State 2: prev was D/L in ISOL form, willing to join. */ - { {NONE,NONE,0}, {NONE,ISOL,2}, {INIT,FINA,1}, {INIT,FINA,3}, {INIT,FINA,4}, {INIT,FINA,6}, }, - - /* State 3: prev was D in FINA form, willing to join. */ - { {NONE,NONE,0}, {NONE,ISOL,2}, {MEDI,FINA,1}, {MEDI,FINA,3}, {MEDI,FINA,4}, {MEDI,FINA,6}, }, - - /* State 4: prev was FINA ALAPH, not willing to join. */ - { {NONE,NONE,0}, {NONE,ISOL,2}, {MED2,ISOL,1}, {MED2,ISOL,2}, {MED2,FIN2,5}, {MED2,ISOL,6}, }, - - /* State 5: prev was FIN2/FIN3 ALAPH, not willing to join. */ - { {NONE,NONE,0}, {NONE,ISOL,2}, {ISOL,ISOL,1}, {ISOL,ISOL,2}, {ISOL,FIN2,5}, {ISOL,ISOL,6}, }, - - /* State 6: prev was DALATH/RISH, not willing to join. */ - { {NONE,NONE,0}, {NONE,ISOL,2}, {NONE,ISOL,1}, {NONE,ISOL,2}, {NONE,FIN3,5}, {NONE,ISOL,6}, } -}; - - -static void -arabic_fallback_shape (const hb_ot_shape_plan_t *plan, - hb_font_t *font, - hb_buffer_t *buffer); - -static void -record_stch (const hb_ot_shape_plan_t *plan, - hb_font_t *font, - hb_buffer_t *buffer); - -static void -collect_features_arabic (hb_ot_shape_planner_t *plan) -{ - hb_ot_map_builder_t *map = &plan->map; - - /* We apply features according to the Arabic spec, with pauses - * in between most. - * - * The pause between init/medi/... and rlig is required. See eg: - * https://bugzilla.mozilla.org/show_bug.cgi?id=644184 - * - * The pauses between init/medi/... themselves are not necessarily - * needed as only one of those features is applied to any character. - * The only difference it makes is when fonts have contextual - * substitutions. We now follow the order of the spec, which makes - * for better experience if that's what Uniscribe is doing. - * - * At least for Arabic, looks like Uniscribe has a pause between - * rlig and calt. Otherwise the IranNastaliq's ALLAH ligature won't - * work. However, testing shows that rlig and calt are applied - * together for Mongolian in Uniscribe. As such, we only add a - * pause for Arabic, not other scripts. - * - * A pause after calt is required to make KFGQPC Uthmanic Script HAFS - * work correctly. See https://github.com/harfbuzz/harfbuzz/issues/505 - */ - - - map->enable_feature (HB_TAG('s','t','c','h')); - map->add_gsub_pause (record_stch); - - map->enable_feature (HB_TAG('c','c','m','p')); - map->enable_feature (HB_TAG('l','o','c','l')); - - map->add_gsub_pause (nullptr); - - for (unsigned int i = 0; i < ARABIC_NUM_FEATURES; i++) - { - bool has_fallback = plan->props.script == HB_SCRIPT_ARABIC && !FEATURE_IS_SYRIAC (arabic_features[i]); - map->add_feature (arabic_features[i], has_fallback ? F_HAS_FALLBACK : F_NONE); - map->add_gsub_pause (nullptr); - } - - /* Normally, Unicode says a ZWNJ means "don't ligate". In Arabic script - * however, it says a ZWJ should also mean "don't ligate". So we run - * the main ligating features as MANUAL_ZWJ. */ - - map->enable_feature (HB_TAG('r','l','i','g'), F_MANUAL_ZWJ | F_HAS_FALLBACK); - - if (plan->props.script == HB_SCRIPT_ARABIC) - map->add_gsub_pause (arabic_fallback_shape); - - /* No pause after rclt. See 98460779bae19e4d64d29461ff154b3527bf8420. */ - map->enable_feature (HB_TAG('r','c','l','t'), F_MANUAL_ZWJ); - map->enable_feature (HB_TAG('c','a','l','t'), F_MANUAL_ZWJ); - map->add_gsub_pause (nullptr); - - /* And undo here. */ - - /* The spec includes 'cswh'. Earlier versions of Windows - * used to enable this by default, but testing suggests - * that Windows 8 and later do not enable it by default, - * and spec now says 'Off by default'. - * We disabled this in ae23c24c32. - * Note that IranNastaliq uses this feature extensively - * to fixup broken glyph sequences. Oh well... - * Test case: U+0643,U+0640,U+0631. */ - //map->enable_feature (HB_TAG('c','s','w','h')); - map->enable_feature (HB_TAG('m','s','e','t')); -} - -#include "hb-ot-shape-complex-arabic-fallback.hh" - -struct arabic_shape_plan_t -{ - /* The "+ 1" in the next array is to accommodate for the "NONE" command, - * which is not an OpenType feature, but this simplifies the code by not - * having to do a "if (... < NONE) ..." and just rely on the fact that - * mask_array[NONE] == 0. */ - hb_mask_t mask_array[ARABIC_NUM_FEATURES + 1]; - - hb_atomic_ptr_t<arabic_fallback_plan_t> fallback_plan; - - unsigned int do_fallback : 1; - unsigned int has_stch : 1; -}; - -void * -data_create_arabic (const hb_ot_shape_plan_t *plan) -{ - arabic_shape_plan_t *arabic_plan = (arabic_shape_plan_t *) calloc (1, sizeof (arabic_shape_plan_t)); - if (unlikely (!arabic_plan)) - return nullptr; - - arabic_plan->do_fallback = plan->props.script == HB_SCRIPT_ARABIC; - arabic_plan->has_stch = !!plan->map.get_1_mask (HB_TAG ('s','t','c','h')); - for (unsigned int i = 0; i < ARABIC_NUM_FEATURES; i++) { - arabic_plan->mask_array[i] = plan->map.get_1_mask (arabic_features[i]); - arabic_plan->do_fallback = arabic_plan->do_fallback && - (FEATURE_IS_SYRIAC (arabic_features[i]) || - plan->map.needs_fallback (arabic_features[i])); - } - - return arabic_plan; -} - -void -data_destroy_arabic (void *data) -{ - arabic_shape_plan_t *arabic_plan = (arabic_shape_plan_t *) data; - - arabic_fallback_plan_destroy (arabic_plan->fallback_plan); - - free (data); -} - -static void -arabic_joining (hb_buffer_t *buffer) -{ - unsigned int count = buffer->len; - hb_glyph_info_t *info = buffer->info; - unsigned int prev = (unsigned int) -1, state = 0; - - /* Check pre-context */ - for (unsigned int i = 0; i < buffer->context_len[0]; i++) - { - unsigned int this_type = get_joining_type (buffer->context[0][i], buffer->unicode->general_category (buffer->context[0][i])); - - if (unlikely (this_type == JOINING_TYPE_T)) - continue; - - const arabic_state_table_entry *entry = &arabic_state_table[state][this_type]; - state = entry->next_state; - break; - } - - for (unsigned int i = 0; i < count; i++) - { - unsigned int this_type = get_joining_type (info[i].codepoint, _hb_glyph_info_get_general_category (&info[i])); - - if (unlikely (this_type == JOINING_TYPE_T)) { - info[i].arabic_shaping_action() = NONE; - continue; - } - - const arabic_state_table_entry *entry = &arabic_state_table[state][this_type]; - - if (entry->prev_action != NONE && prev != (unsigned int) -1) - { - info[prev].arabic_shaping_action() = entry->prev_action; - buffer->unsafe_to_break (prev, i + 1); - } - - info[i].arabic_shaping_action() = entry->curr_action; - - prev = i; - state = entry->next_state; - } - - for (unsigned int i = 0; i < buffer->context_len[1]; i++) - { - unsigned int this_type = get_joining_type (buffer->context[1][i], buffer->unicode->general_category (buffer->context[1][i])); - - if (unlikely (this_type == JOINING_TYPE_T)) - continue; - - const arabic_state_table_entry *entry = &arabic_state_table[state][this_type]; - if (entry->prev_action != NONE && prev != (unsigned int) -1) - info[prev].arabic_shaping_action() = entry->prev_action; - break; - } -} - -static void -mongolian_variation_selectors (hb_buffer_t *buffer) -{ - /* Copy arabic_shaping_action() from base to Mongolian variation selectors. */ - unsigned int count = buffer->len; - hb_glyph_info_t *info = buffer->info; - for (unsigned int i = 1; i < count; i++) - if (unlikely (hb_in_range<hb_codepoint_t> (info[i].codepoint, 0x180Bu, 0x180Du))) - info[i].arabic_shaping_action() = info[i - 1].arabic_shaping_action(); -} - -void -setup_masks_arabic_plan (const arabic_shape_plan_t *arabic_plan, - hb_buffer_t *buffer, - hb_script_t script) -{ - HB_BUFFER_ALLOCATE_VAR (buffer, arabic_shaping_action); - - arabic_joining (buffer); - if (script == HB_SCRIPT_MONGOLIAN) - mongolian_variation_selectors (buffer); - - unsigned int count = buffer->len; - hb_glyph_info_t *info = buffer->info; - for (unsigned int i = 0; i < count; i++) - info[i].mask |= arabic_plan->mask_array[info[i].arabic_shaping_action()]; -} - -static void -setup_masks_arabic (const hb_ot_shape_plan_t *plan, - hb_buffer_t *buffer, - hb_font_t *font HB_UNUSED) -{ - const arabic_shape_plan_t *arabic_plan = (const arabic_shape_plan_t *) plan->data; - setup_masks_arabic_plan (arabic_plan, buffer, plan->props.script); -} - -static void -arabic_fallback_shape (const hb_ot_shape_plan_t *plan, - hb_font_t *font, - hb_buffer_t *buffer) -{ -#ifdef HB_NO_OT_SHAPE_COMPLEX_ARABIC_FALLBACK - return; -#endif - - const arabic_shape_plan_t *arabic_plan = (const arabic_shape_plan_t *) plan->data; - - if (!arabic_plan->do_fallback) - return; - -retry: - arabic_fallback_plan_t *fallback_plan = arabic_plan->fallback_plan; - if (unlikely (!fallback_plan)) - { - /* This sucks. We need a font to build the fallback plan... */ - fallback_plan = arabic_fallback_plan_create (plan, font); - if (unlikely (!arabic_plan->fallback_plan.cmpexch (nullptr, fallback_plan))) - { - arabic_fallback_plan_destroy (fallback_plan); - goto retry; - } - } - - arabic_fallback_plan_shape (fallback_plan, font, buffer); -} - -/* - * Stretch feature: "stch". - * See example here: - * https://docs.microsoft.com/en-us/typography/script-development/syriac - * We implement this in a generic way, such that the Arabic subtending - * marks can use it as well. - */ - -static void -record_stch (const hb_ot_shape_plan_t *plan, - hb_font_t *font HB_UNUSED, - hb_buffer_t *buffer) -{ - const arabic_shape_plan_t *arabic_plan = (const arabic_shape_plan_t *) plan->data; - if (!arabic_plan->has_stch) - return; - - /* 'stch' feature was just applied. Look for anything that multiplied, - * and record it for stch treatment later. Note that rtlm, frac, etc - * are applied before stch, but we assume that they didn't result in - * anything multiplying into 5 pieces, so it's safe-ish... */ - - unsigned int count = buffer->len; - hb_glyph_info_t *info = buffer->info; - for (unsigned int i = 0; i < count; i++) - if (unlikely (_hb_glyph_info_multiplied (&info[i]))) - { - unsigned int comp = _hb_glyph_info_get_lig_comp (&info[i]); - info[i].arabic_shaping_action() = comp % 2 ? STCH_REPEATING : STCH_FIXED; - buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_ARABIC_HAS_STCH; - } -} - -static void -apply_stch (const hb_ot_shape_plan_t *plan HB_UNUSED, - hb_buffer_t *buffer, - hb_font_t *font) -{ - if (likely (!(buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_ARABIC_HAS_STCH))) - return; - - /* The Arabic shaper currently always processes in RTL mode, so we should - * stretch / position the stretched pieces to the left / preceding glyphs. */ - - /* We do a two pass implementation: - * First pass calculates the exact number of extra glyphs we need, - * We then enlarge buffer to have that much room, - * Second pass applies the stretch, copying things to the end of buffer. - */ - - int sign = font->x_scale < 0 ? -1 : +1; - unsigned int extra_glyphs_needed = 0; // Set during MEASURE, used during CUT - enum { MEASURE, CUT } /* step_t */; - - for (unsigned int step = MEASURE; step <= CUT; step = step + 1) - { - unsigned int count = buffer->len; - hb_glyph_info_t *info = buffer->info; - hb_glyph_position_t *pos = buffer->pos; - unsigned int new_len = count + extra_glyphs_needed; // write head during CUT - unsigned int j = new_len; - for (unsigned int i = count; i; i--) - { - if (!hb_in_range<uint8_t> (info[i - 1].arabic_shaping_action(), STCH_FIXED, STCH_REPEATING)) - { - if (step == CUT) - { - --j; - info[j] = info[i - 1]; - pos[j] = pos[i - 1]; - } - continue; - } - - /* Yay, justification! */ - - hb_position_t w_total = 0; // Total to be filled - hb_position_t w_fixed = 0; // Sum of fixed tiles - hb_position_t w_repeating = 0; // Sum of repeating tiles - int n_fixed = 0; - int n_repeating = 0; - - unsigned int end = i; - while (i && - hb_in_range<uint8_t> (info[i - 1].arabic_shaping_action(), STCH_FIXED, STCH_REPEATING)) - { - i--; - hb_position_t width = font->get_glyph_h_advance (info[i].codepoint); - if (info[i].arabic_shaping_action() == STCH_FIXED) - { - w_fixed += width; - n_fixed++; - } - else - { - w_repeating += width; - n_repeating++; - } - } - unsigned int start = i; - unsigned int context = i; - while (context && - !hb_in_range<uint8_t> (info[context - 1].arabic_shaping_action(), STCH_FIXED, STCH_REPEATING) && - (_hb_glyph_info_is_default_ignorable (&info[context - 1]) || - HB_ARABIC_GENERAL_CATEGORY_IS_WORD (_hb_glyph_info_get_general_category (&info[context - 1])))) - { - context--; - w_total += pos[context].x_advance; - } - i++; // Don't touch i again. - - DEBUG_MSG (ARABIC, nullptr, "%s stretch at (%d,%d,%d)", - step == MEASURE ? "measuring" : "cutting", context, start, end); - DEBUG_MSG (ARABIC, nullptr, "rest of word: count=%d width %d", start - context, w_total); - DEBUG_MSG (ARABIC, nullptr, "fixed tiles: count=%d width=%d", n_fixed, w_fixed); - DEBUG_MSG (ARABIC, nullptr, "repeating tiles: count=%d width=%d", n_repeating, w_repeating); - - /* Number of additional times to repeat each repeating tile. */ - int n_copies = 0; - - hb_position_t w_remaining = w_total - w_fixed; - if (sign * w_remaining > sign * w_repeating && sign * w_repeating > 0) - n_copies = (sign * w_remaining) / (sign * w_repeating) - 1; - - /* See if we can improve the fit by adding an extra repeat and squeezing them together a bit. */ - hb_position_t extra_repeat_overlap = 0; - hb_position_t shortfall = sign * w_remaining - sign * w_repeating * (n_copies + 1); - if (shortfall > 0 && n_repeating > 0) - { - ++n_copies; - hb_position_t excess = (n_copies + 1) * sign * w_repeating - sign * w_remaining; - if (excess > 0) - extra_repeat_overlap = excess / (n_copies * n_repeating); - } - - if (step == MEASURE) - { - extra_glyphs_needed += n_copies * n_repeating; - DEBUG_MSG (ARABIC, nullptr, "will add extra %d copies of repeating tiles", n_copies); - } - else - { - buffer->unsafe_to_break (context, end); - hb_position_t x_offset = 0; - for (unsigned int k = end; k > start; k--) - { - hb_position_t width = font->get_glyph_h_advance (info[k - 1].codepoint); - - unsigned int repeat = 1; - if (info[k - 1].arabic_shaping_action() == STCH_REPEATING) - repeat += n_copies; - - DEBUG_MSG (ARABIC, nullptr, "appending %d copies of glyph %d; j=%d", - repeat, info[k - 1].codepoint, j); - for (unsigned int n = 0; n < repeat; n++) - { - x_offset -= width; - if (n > 0) - x_offset += extra_repeat_overlap; - pos[k - 1].x_offset = x_offset; - /* Append copy. */ - --j; - info[j] = info[k - 1]; - pos[j] = pos[k - 1]; - } - } - } - } - - if (step == MEASURE) - { - if (unlikely (!buffer->ensure (count + extra_glyphs_needed))) - break; - } - else - { - assert (j == 0); - buffer->len = new_len; - } - } -} - - -static void -postprocess_glyphs_arabic (const hb_ot_shape_plan_t *plan, - hb_buffer_t *buffer, - hb_font_t *font) -{ - apply_stch (plan, buffer, font); - - HB_BUFFER_DEALLOCATE_VAR (buffer, arabic_shaping_action); -} - -/* http://www.unicode.org/reports/tr53/ */ - -static hb_codepoint_t -modifier_combining_marks[] = -{ - 0x0654u, /* ARABIC HAMZA ABOVE */ - 0x0655u, /* ARABIC HAMZA BELOW */ - 0x0658u, /* ARABIC MARK NOON GHUNNA */ - 0x06DCu, /* ARABIC SMALL HIGH SEEN */ - 0x06E3u, /* ARABIC SMALL LOW SEEN */ - 0x06E7u, /* ARABIC SMALL HIGH YEH */ - 0x06E8u, /* ARABIC SMALL HIGH NOON */ - 0x08D3u, /* ARABIC SMALL LOW WAW */ - 0x08F3u, /* ARABIC SMALL HIGH WAW */ -}; - -static inline bool -info_is_mcm (const hb_glyph_info_t &info) -{ - hb_codepoint_t u = info.codepoint; - for (unsigned int i = 0; i < ARRAY_LENGTH (modifier_combining_marks); i++) - if (u == modifier_combining_marks[i]) - return true; - return false; -} - -static void -reorder_marks_arabic (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; - - DEBUG_MSG (ARABIC, buffer, "Reordering marks from %d to %d", start, end); - - unsigned int i = start; - for (unsigned int cc = 220; cc <= 230; cc += 10) - { - DEBUG_MSG (ARABIC, buffer, "Looking for %d's starting at %d", cc, i); - while (i < end && info_cc(info[i]) < cc) - i++; - DEBUG_MSG (ARABIC, buffer, "Looking for %d's stopped at %d", cc, i); - - if (i == end) - break; - - if (info_cc(info[i]) > cc) - continue; - - unsigned int j = i; - while (j < end && info_cc(info[j]) == cc && info_is_mcm (info[j])) - j++; - - if (i == j) - continue; - - DEBUG_MSG (ARABIC, buffer, "Found %d's from %d to %d", cc, i, j); - - /* Shift it! */ - DEBUG_MSG (ARABIC, buffer, "Shifting %d's: %d %d", cc, i, j); - hb_glyph_info_t temp[HB_OT_SHAPE_COMPLEX_MAX_COMBINING_MARKS]; - assert (j - i <= ARRAY_LENGTH (temp)); - buffer->merge_clusters (start, j); - memmove (temp, &info[i], (j - i) * sizeof (hb_glyph_info_t)); - memmove (&info[start + j - i], &info[start], (i - start) * sizeof (hb_glyph_info_t)); - memmove (&info[start], temp, (j - i) * sizeof (hb_glyph_info_t)); - - /* Renumber CC such that the reordered sequence is still sorted. - * 22 and 26 are chosen because they are smaller than all Arabic categories, - * and are folded back to 220/230 respectively during fallback mark positioning. - * - * We do this because the CGJ-handling logic in the normalizer relies on - * mark sequences having an increasing order even after this reordering. - * https://github.com/harfbuzz/harfbuzz/issues/554 - * This, however, does break some obscure sequences, where the normalizer - * might compose a sequence that it should not. For example, in the seequence - * ALEF, HAMZAH, MADDAH, we should NOT try to compose ALEF+MADDAH, but with this - * renumbering, we will. - */ - unsigned int new_start = start + j - i; - unsigned int new_cc = cc == 220 ? HB_MODIFIED_COMBINING_CLASS_CCC22 : HB_MODIFIED_COMBINING_CLASS_CCC26; - while (start < new_start) - { - _hb_glyph_info_set_modified_combining_class (&info[start], new_cc); - start++; - } - - i = j; - } -} - -const hb_ot_complex_shaper_t _hb_ot_complex_shaper_arabic = -{ - collect_features_arabic, - nullptr, /* override_features */ - data_create_arabic, - data_destroy_arabic, - nullptr, /* preprocess_text */ - postprocess_glyphs_arabic, - HB_OT_SHAPE_NORMALIZATION_MODE_DEFAULT, - nullptr, /* decompose */ - nullptr, /* compose */ - setup_masks_arabic, - HB_TAG_NONE, /* gpos_tag */ - reorder_marks_arabic, - HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE, - true, /* fallback_position */ -}; - - -#endif |