|  | /* | 
|  | * 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 sea_category() complex_var_u8_0() /* indic_category_t */ | 
|  | #define sea_position() complex_var_u8_1() /* indic_position_t */ | 
|  |  | 
|  |  | 
|  | /* | 
|  | * South-East Asian shaper. | 
|  | * Loosely based on the Myanmar spec / shaper. | 
|  | * There is no OpenType spec for this. | 
|  | */ | 
|  |  | 
|  | static const hb_tag_t | 
|  | basic_features[] = | 
|  | { | 
|  | /* | 
|  | * Basic features. | 
|  | * These features are applied in order, one at a time, after initial_reordering. | 
|  | */ | 
|  | HB_TAG('p','r','e','f'), | 
|  | HB_TAG('a','b','v','f'), | 
|  | HB_TAG('b','l','w','f'), | 
|  | HB_TAG('p','s','t','f'), | 
|  | }; | 
|  | static const hb_tag_t | 
|  | other_features[] = | 
|  | { | 
|  | /* | 
|  | * 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'), | 
|  | }; | 
|  |  | 
|  | 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_sea (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); | 
|  |  | 
|  | 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. */ | 
|  | map->add_global_bool_feature (HB_TAG('c','c','m','p')); | 
|  |  | 
|  | map->add_gsub_pause (initial_reordering); | 
|  | for (unsigned int i = 0; i < ARRAY_LENGTH (basic_features); i++) | 
|  | { | 
|  | map->add_feature (basic_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ); | 
|  | map->add_gsub_pause (NULL); | 
|  | } | 
|  | map->add_gsub_pause (final_reordering); | 
|  | for (unsigned int i = 0; i < ARRAY_LENGTH (other_features); i++) | 
|  | map->add_feature (other_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ); | 
|  | } | 
|  |  | 
|  | static void | 
|  | override_features_sea (hb_ot_shape_planner_t *plan) | 
|  | { | 
|  | plan->map.add_feature (HB_TAG('l','i','g','a'), 0, F_GLOBAL); | 
|  | } | 
|  |  | 
|  |  | 
|  | enum syllable_type_t { | 
|  | consonant_syllable, | 
|  | broken_cluster, | 
|  | non_sea_cluster, | 
|  | }; | 
|  |  | 
|  | #include "hb-ot-shape-complex-sea-machine.hh" | 
|  |  | 
|  |  | 
|  | /* Note: This enum is duplicated in the -machine.rl source file. | 
|  | * Not sure how to avoid duplication. */ | 
|  | enum sea_category_t { | 
|  | //  OT_C    = 1, | 
|  | OT_GB   = 12, /* Generic Base XXX DOTTED CIRCLE only for now */ | 
|  | //  OT_H    = 4,  /* Halant */ | 
|  | OT_IV   = 2,  /* Independent Vowel */ | 
|  | OT_MR   = 22, /* Medial Ra */ | 
|  | //  OT_CM   = 17, /* Consonant Medial */ | 
|  | OT_VAbv = 26, | 
|  | OT_VBlw = 27, | 
|  | OT_VPre = 28, | 
|  | OT_VPst = 29, | 
|  | OT_T    = 3,  /* Tone Marks */ | 
|  | //  OT_A    = 10, /* Anusvara */ | 
|  | }; | 
|  |  | 
|  | static inline void | 
|  | set_sea_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 & 0x7Fu); | 
|  | indic_position_t pos = (indic_position_t) (type >> 8); | 
|  |  | 
|  | /* Medial Ra */ | 
|  | if (u == 0x1A55u || u == 0xAA34u) | 
|  | cat = (indic_category_t) OT_MR; | 
|  |  | 
|  | if (cat == OT_M) | 
|  | { | 
|  | switch ((int) pos) | 
|  | { | 
|  | case POS_PRE_C:	cat = (indic_category_t) OT_VPre; 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.sea_category() = (sea_category_t) cat; | 
|  | info.sea_position() = pos; | 
|  | } | 
|  |  | 
|  |  | 
|  | static void | 
|  | setup_masks_sea (const hb_ot_shape_plan_t *plan HB_UNUSED, | 
|  | hb_buffer_t              *buffer, | 
|  | hb_font_t                *font HB_UNUSED) | 
|  | { | 
|  | HB_BUFFER_ALLOCATE_VAR (buffer, sea_category); | 
|  | HB_BUFFER_ALLOCATE_VAR (buffer, sea_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; | 
|  | hb_glyph_info_t *info = buffer->info; | 
|  | for (unsigned int i = 0; i < count; i++) | 
|  | set_sea_properties (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_sea_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb) | 
|  | { | 
|  | int a = pa->sea_position(); | 
|  | int b = pb->sea_position(); | 
|  |  | 
|  | return a < b ? -1 : a == b ? 0 : +1; | 
|  | } | 
|  |  | 
|  |  | 
|  | 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 = start; | 
|  |  | 
|  | /* Reorder! */ | 
|  | unsigned int i = start; | 
|  | for (; i < base; i++) | 
|  | info[i].sea_position() = POS_PRE_C; | 
|  | if (i < end) | 
|  | { | 
|  | info[i].sea_position() = POS_BASE_C; | 
|  | i++; | 
|  | } | 
|  | for (; i < end; i++) | 
|  | { | 
|  | if (info[i].sea_category() == OT_MR) /* Pre-base reordering */ | 
|  | { | 
|  | info[i].sea_position() = POS_PRE_C; | 
|  | continue; | 
|  | } | 
|  | if (info[i].sea_category() == OT_VPre) /* Left matra */ | 
|  | { | 
|  | info[i].sea_position() = POS_PRE_M; | 
|  | continue; | 
|  | } | 
|  |  | 
|  | info[i].sea_position() = POS_AFTER_MAIN; | 
|  | } | 
|  |  | 
|  | buffer->merge_clusters (start, end); | 
|  | /* Sit tight, rock 'n roll! */ | 
|  | hb_bubble_sort (info + start, end - start, compare_sea_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_sea_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_sea_cluster:		initial_reordering_non_sea_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; | 
|  | hb_glyph_info_t *info = buffer->info; | 
|  | for (unsigned int i = 0; i < count; i++) | 
|  | if ((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 (0x25CCu, 0, &dottedcircle_glyph)) | 
|  | return; | 
|  |  | 
|  | hb_glyph_info_t dottedcircle = {0}; | 
|  | dottedcircle.codepoint = 0x25CCu; | 
|  | set_sea_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, sea_category); | 
|  | HB_BUFFER_DEALLOCATE_VAR (buffer, sea_position); | 
|  | } | 
|  |  | 
|  |  | 
|  | const hb_ot_complex_shaper_t _hb_ot_complex_shaper_sea = | 
|  | { | 
|  | "sea", | 
|  | collect_features_sea, | 
|  | override_features_sea, | 
|  | NULL, /* data_create */ | 
|  | NULL, /* data_destroy */ | 
|  | NULL, /* preprocess_text */ | 
|  | HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT, | 
|  | NULL, /* decompose */ | 
|  | NULL, /* compose */ | 
|  | setup_masks_sea, | 
|  | HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE, | 
|  | false, /* fallback_position */ | 
|  | }; |