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 | 356 |
1 files changed, 356 insertions, 0 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 new file mode 100644 index 0000000000..a57e81a5ec --- /dev/null +++ b/src/3rdparty/harfbuzz-ng/src/hb-ot-shape-complex-arabic.cc @@ -0,0 +1,356 @@ +/* + * 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-ot-shape-complex-private.hh" +#include "hb-ot-shape-private.hh" + + +/* buffer var allocations */ +#define arabic_shaping_action() complex_var_u8_0() /* arabic shaping action */ + + +/* + * Bits used in the joining tables + */ +enum { + 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. */ +}; + +/* + * Joining types: + */ + +#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) +{ + if (likely (hb_in_range<hb_codepoint_t> (u, JOINING_TABLE_FIRST, JOINING_TABLE_LAST))) { + unsigned int j_type = joining_table[u - JOINING_TABLE_FIRST]; + if (likely (j_type != JOINING_TYPE_X)) + return j_type; + } + + /* Mongolian joining data is not in ArabicJoining.txt yet. */ + if (unlikely (hb_in_range<hb_codepoint_t> (u, 0x1800, 0x18AF))) + { + if (unlikely (hb_in_range<hb_codepoint_t> (u, 0x1880, 0x1886))) + return JOINING_TYPE_U; + + /* All letters, SIBE SYLLABLE BOUNDARY MARKER, and NIRUGU are D */ + if ((FLAG(gen_cat) & (FLAG (HB_UNICODE_GENERAL_CATEGORY_OTHER_LETTER) | + FLAG (HB_UNICODE_GENERAL_CATEGORY_MODIFIER_LETTER))) + || u == 0x1807 || u == 0x180A) + return JOINING_TYPE_D; + } + + /* 'Phags-pa joining data is not in ArabicJoining.txt yet. */ + if (unlikely (hb_in_range<hb_codepoint_t> (u, 0xA840, 0xA872))) + { + if (unlikely (u == 0xA872)) + return JOINING_TYPE_L; + + return JOINING_TYPE_D; + } + + if (unlikely (hb_in_range<hb_codepoint_t> (u, 0x200C, 0x200D))) + { + return u == 0x200C ? JOINING_TYPE_U : JOINING_TYPE_C; + } + + return (FLAG(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; +} + +static const hb_tag_t arabic_features[] = +{ + HB_TAG('i','n','i','t'), + HB_TAG('m','e','d','i'), + HB_TAG('f','i','n','a'), + HB_TAG('i','s','o','l'), + /* Syriac */ + HB_TAG('m','e','d','2'), + HB_TAG('f','i','n','2'), + HB_TAG('f','i','n','3'), + HB_TAG_NONE +}; + + +/* Same order as the feature array */ +enum { + INIT, + MEDI, + FINA, + ISOL, + + /* Syriac */ + MED2, + FIN2, + FIN3, + + NONE, + + ARABIC_NUM_FEATURES = NONE +}; + +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 +collect_features_arabic (hb_ot_shape_planner_t *plan) +{ + hb_ot_map_builder_t *map = &plan->map; + + /* For Language forms (in ArabicOT speak), we do the iso/fina/medi/init together, + * then rlig and calt each in their own stage. This makes IranNastaliq's ALLAH + * ligature work correctly. It's unfortunate though... + * + * This also makes Arial Bold in Windows7 work. See: + * https://bugzilla.mozilla.org/show_bug.cgi?id=644184 + * + * TODO: Add test cases for these two. + */ + + map->add_global_bool_feature (HB_TAG('c','c','m','p')); + map->add_global_bool_feature (HB_TAG('l','o','c','l')); + + map->add_gsub_pause (NULL); + + for (unsigned int i = 0; i < ARABIC_NUM_FEATURES; i++) + map->add_feature (arabic_features[i], 1, i < 4 ? F_HAS_FALLBACK : F_NONE); /* The first four features have fallback. */ + + map->add_gsub_pause (NULL); + + map->add_feature (HB_TAG('r','l','i','g'), 1, F_GLOBAL|F_HAS_FALLBACK); + map->add_gsub_pause (arabic_fallback_shape); + + map->add_global_bool_feature (HB_TAG('c','a','l','t')); + map->add_gsub_pause (NULL); + + map->add_global_bool_feature (HB_TAG('c','s','w','h')); + map->add_global_bool_feature (HB_TAG('m','s','e','t')); +} + +#include "hb-ot-shape-complex-arabic-fallback.hh" + +struct arabic_shape_plan_t +{ + ASSERT_POD (); + + /* 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]; + + bool do_fallback; + arabic_fallback_plan_t *fallback_plan; +}; + +static 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 NULL; + + arabic_plan->do_fallback = plan->props.script == HB_SCRIPT_ARABIC; + for (unsigned int i = 0; i < ARABIC_NUM_FEATURES; i++) { + arabic_plan->mask_array[i] = plan->map.get_1_mask (arabic_features[i]); + if (i < 4) + arabic_plan->do_fallback = arabic_plan->do_fallback && plan->map.needs_fallback (arabic_features[i]); + } + + return arabic_plan; +} + +static 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; + unsigned int prev = (unsigned int) -1, state = 0; + + HB_BUFFER_ALLOCATE_VAR (buffer, arabic_shaping_action); + + /* Check pre-context */ + if (!(buffer->flags & HB_BUFFER_FLAG_BOT)) + 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 (buffer->info[i].codepoint, _hb_glyph_info_get_general_category (&buffer->info[i])); + + if (unlikely (this_type == JOINING_TYPE_T)) { + buffer->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) + buffer->info[prev].arabic_shaping_action() = entry->prev_action; + + buffer->info[i].arabic_shaping_action() = entry->curr_action; + + prev = i; + state = entry->next_state; + } + + if (!(buffer->flags & HB_BUFFER_FLAG_EOT)) + 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) + buffer->info[prev].arabic_shaping_action() = entry->prev_action; + break; + } + + + HB_BUFFER_DEALLOCATE_VAR (buffer, 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; + + arabic_joining (buffer); + unsigned int count = buffer->len; + for (unsigned int i = 0; i < count; i++) + buffer->info[i].mask |= arabic_plan->mask_array[buffer->info[i].arabic_shaping_action()]; +} + + +static void +arabic_fallback_shape (const hb_ot_shape_plan_t *plan, + hb_font_t *font, + hb_buffer_t *buffer) +{ + 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_fallback_plan_t *) hb_atomic_ptr_get (&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 (!hb_atomic_ptr_cmpexch (&(const_cast<arabic_shape_plan_t *> (arabic_plan))->fallback_plan, NULL, fallback_plan))) { + arabic_fallback_plan_destroy (fallback_plan); + goto retry; + } + } + + arabic_fallback_plan_shape (fallback_plan, font, buffer); +} + + +const hb_ot_complex_shaper_t _hb_ot_complex_shaper_arabic = +{ + "arabic", + collect_features_arabic, + NULL, /* override_features */ + data_create_arabic, + data_destroy_arabic, + NULL, /* preprocess_text_arabic */ + NULL, /* normalization_preference */ + NULL, /* decompose */ + NULL, /* compose */ + setup_masks_arabic, + HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE, + true, /* fallback_position */ +}; |