/* * Copyright © 2015 Mozilla Foundation. * Copyright © 2015 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. * * Mozilla Author(s): Jonathan Kew * Google Author(s): Behdad Esfahbod */ #include "hb.hh" #ifndef HB_NO_OT_SHAPE #include "hb-ot-shape-complex-use.hh" #include "hb-ot-shape-complex-arabic.hh" #include "hb-ot-shape-complex-vowel-constraints.hh" /* buffer var allocations */ #define use_category() complex_var_u8_0() /* * Universal Shaping Engine. * https://docs.microsoft.com/en-us/typography/script-development/use */ static const hb_tag_t use_basic_features[] = { /* * Basic features. * These features are applied all at once, before reordering. */ HB_TAG('r','k','r','f'), HB_TAG('a','b','v','f'), HB_TAG('b','l','w','f'), HB_TAG('h','a','l','f'), HB_TAG('p','s','t','f'), HB_TAG('v','a','t','u'), HB_TAG('c','j','c','t'), }; static const hb_tag_t use_topographical_features[] = { HB_TAG('i','s','o','l'), HB_TAG('i','n','i','t'), HB_TAG('m','e','d','i'), HB_TAG('f','i','n','a'), }; /* Same order as use_topographical_features. */ enum joining_form_t { USE_ISOL, USE_INIT, USE_MEDI, USE_FINA, _USE_NONE }; static const hb_tag_t use_other_features[] = { /* * Other features. * These features are applied all at once, after reordering and * clearing syllables. */ HB_TAG('a','b','v','s'), HB_TAG('b','l','w','s'), HB_TAG('h','a','l','n'), HB_TAG('p','r','e','s'), HB_TAG('p','s','t','s'), }; static const hb_tag_t use_positioning_features[] = { /* * Positioning features. * We don't care about the types. */ HB_TAG('d','i','s','t'), HB_TAG('a','b','v','m'), HB_TAG('b','l','w','m'), }; static void setup_syllables_use (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer); static void record_rphf_use (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer); static void record_pref_use (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer); static void reorder_use (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer); static void collect_features_use (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_use); /* "Default glyph pre-processing group" */ map->enable_feature (HB_TAG('l','o','c','l')); map->enable_feature (HB_TAG('c','c','m','p')); map->enable_feature (HB_TAG('n','u','k','t')); map->enable_feature (HB_TAG('a','k','h','n'), F_MANUAL_ZWJ); /* "Reordering group" */ map->add_gsub_pause (_hb_clear_substitution_flags); map->add_feature (HB_TAG('r','p','h','f'), F_MANUAL_ZWJ); map->add_gsub_pause (record_rphf_use); map->add_gsub_pause (_hb_clear_substitution_flags); map->enable_feature (HB_TAG('p','r','e','f'), F_MANUAL_ZWJ); map->add_gsub_pause (record_pref_use); /* "Orthographic unit shaping group" */ for (unsigned int i = 0; i < ARRAY_LENGTH (use_basic_features); i++) map->enable_feature (use_basic_features[i], F_MANUAL_ZWJ); map->add_gsub_pause (reorder_use); map->add_gsub_pause (_hb_clear_syllables); /* "Topographical features" */ for (unsigned int i = 0; i < ARRAY_LENGTH (use_topographical_features); i++) map->add_feature (use_topographical_features[i]); map->add_gsub_pause (nullptr); /* "Standard typographic presentation" */ for (unsigned int i = 0; i < ARRAY_LENGTH (use_other_features); i++) map->enable_feature (use_other_features[i], F_MANUAL_ZWJ); /* "Positional feature application" */ for (unsigned int i = 0; i < ARRAY_LENGTH (use_positioning_features); i++) map->enable_feature (use_positioning_features[i]); } struct use_shape_plan_t { hb_mask_t rphf_mask; arabic_shape_plan_t *arabic_plan; }; static bool has_arabic_joining (hb_script_t script) { /* List of scripts that have data in arabic-table. */ switch ((int) script) { /* Unicode-1.1 additions */ case HB_SCRIPT_ARABIC: /* Unicode-3.0 additions */ case HB_SCRIPT_MONGOLIAN: case HB_SCRIPT_SYRIAC: /* Unicode-5.0 additions */ case HB_SCRIPT_NKO: case HB_SCRIPT_PHAGS_PA: /* Unicode-6.0 additions */ case HB_SCRIPT_MANDAIC: /* Unicode-7.0 additions */ case HB_SCRIPT_MANICHAEAN: case HB_SCRIPT_PSALTER_PAHLAVI: /* Unicode-9.0 additions */ case HB_SCRIPT_ADLAM: return true; default: return false; } } static void * data_create_use (const hb_ot_shape_plan_t *plan) { use_shape_plan_t *use_plan = (use_shape_plan_t *) calloc (1, sizeof (use_shape_plan_t)); if (unlikely (!use_plan)) return nullptr; use_plan->rphf_mask = plan->map.get_1_mask (HB_TAG('r','p','h','f')); if (has_arabic_joining (plan->props.script)) { use_plan->arabic_plan = (arabic_shape_plan_t *) data_create_arabic (plan); if (unlikely (!use_plan->arabic_plan)) { free (use_plan); return nullptr; } } return use_plan; } static void data_destroy_use (void *data) { use_shape_plan_t *use_plan = (use_shape_plan_t *) data; if (use_plan->arabic_plan) data_destroy_arabic (use_plan->arabic_plan); free (data); } enum use_syllable_type_t { use_independent_cluster, use_virama_terminated_cluster, use_sakot_terminated_cluster, use_standard_cluster, use_number_joiner_terminated_cluster, use_numeral_cluster, use_symbol_cluster, use_broken_cluster, use_non_cluster, }; #include "hb-ot-shape-complex-use-machine.hh" static void setup_masks_use (const hb_ot_shape_plan_t *plan, hb_buffer_t *buffer, hb_font_t *font HB_UNUSED) { const use_shape_plan_t *use_plan = (const use_shape_plan_t *) plan->data; /* Do this before allocating use_category(). */ if (use_plan->arabic_plan) { setup_masks_arabic_plan (use_plan->arabic_plan, buffer, plan->props.script); } HB_BUFFER_ALLOCATE_VAR (buffer, use_category); /* 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++) info[i].use_category() = hb_use_get_category (info[i].codepoint); } static void setup_rphf_mask (const hb_ot_shape_plan_t *plan, hb_buffer_t *buffer) { const use_shape_plan_t *use_plan = (const use_shape_plan_t *) plan->data; hb_mask_t mask = use_plan->rphf_mask; if (!mask) return; hb_glyph_info_t *info = buffer->info; foreach_syllable (buffer, start, end) { unsigned int limit = info[start].use_category() == USE_R ? 1 : hb_min (3u, end - start); for (unsigned int i = start; i < start + limit; i++) info[i].mask |= mask; } } static void setup_topographical_masks (const hb_ot_shape_plan_t *plan, hb_buffer_t *buffer) { const use_shape_plan_t *use_plan = (const use_shape_plan_t *) plan->data; if (use_plan->arabic_plan) return; static_assert ((USE_INIT < 4 && USE_ISOL < 4 && USE_MEDI < 4 && USE_FINA < 4), ""); hb_mask_t masks[4], all_masks = 0; for (unsigned int i = 0; i < 4; i++) { masks[i] = plan->map.get_1_mask (use_topographical_features[i]); if (masks[i] == plan->map.get_global_mask ()) masks[i] = 0; all_masks |= masks[i]; } if (!all_masks) return; hb_mask_t other_masks = ~all_masks; unsigned int last_start = 0; joining_form_t last_form = _USE_NONE; hb_glyph_info_t *info = buffer->info; foreach_syllable (buffer, start, end) { use_syllable_type_t syllable_type = (use_syllable_type_t) (info[start].syllable() & 0x0F); switch (syllable_type) { case use_independent_cluster: case use_symbol_cluster: case use_non_cluster: /* These don't join. Nothing to do. */ last_form = _USE_NONE; break; case use_virama_terminated_cluster: case use_sakot_terminated_cluster: case use_standard_cluster: case use_number_joiner_terminated_cluster: case use_numeral_cluster: case use_broken_cluster: bool join = last_form == USE_FINA || last_form == USE_ISOL; if (join) { /* Fixup previous syllable's form. */ last_form = last_form == USE_FINA ? USE_MEDI : USE_INIT; for (unsigned int i = last_start; i < start; i++) info[i].mask = (info[i].mask & other_masks) | masks[last_form]; } /* Form for this syllable. */ last_form = join ? USE_FINA : USE_ISOL; for (unsigned int i = start; i < end; i++) info[i].mask = (info[i].mask & other_masks) | masks[last_form]; break; } last_start = start; } } static void setup_syllables_use (const hb_ot_shape_plan_t *plan, hb_font_t *font HB_UNUSED, hb_buffer_t *buffer) { find_syllables_use (buffer); foreach_syllable (buffer, start, end) buffer->unsafe_to_break (start, end); setup_rphf_mask (plan, buffer); setup_topographical_masks (plan, buffer); } static void record_rphf_use (const hb_ot_shape_plan_t *plan, hb_font_t *font HB_UNUSED, hb_buffer_t *buffer) { const use_shape_plan_t *use_plan = (const use_shape_plan_t *) plan->data; hb_mask_t mask = use_plan->rphf_mask; if (!mask) return; hb_glyph_info_t *info = buffer->info; foreach_syllable (buffer, start, end) { /* Mark a substituted repha as USE_R. */ for (unsigned int i = start; i < end && (info[i].mask & mask); i++) if (_hb_glyph_info_substituted (&info[i])) { info[i].use_category() = USE_R; break; } } } static void record_pref_use (const hb_ot_shape_plan_t *plan HB_UNUSED, hb_font_t *font HB_UNUSED, hb_buffer_t *buffer) { hb_glyph_info_t *info = buffer->info; foreach_syllable (buffer, start, end) { /* Mark a substituted pref as VPre, as they behave the same way. */ for (unsigned int i = start; i < end; i++) if (_hb_glyph_info_substituted (&info[i])) { info[i].use_category() = USE_VPre; break; } } } static inline bool is_halant (const hb_glyph_info_t &info) { return (info.use_category() == USE_H || info.use_category() == USE_HVM) && !_hb_glyph_info_ligated (&info); } static void reorder_syllable_use (hb_buffer_t *buffer, unsigned int start, unsigned int end) { use_syllable_type_t syllable_type = (use_syllable_type_t) (buffer->info[start].syllable() & 0x0F); /* Only a few syllable types need reordering. */ if (unlikely (!(FLAG_UNSAFE (syllable_type) & (FLAG (use_virama_terminated_cluster) | FLAG (use_sakot_terminated_cluster) | FLAG (use_standard_cluster) | FLAG (use_broken_cluster) | 0)))) return; hb_glyph_info_t *info = buffer->info; #define POST_BASE_FLAGS64 (FLAG64 (USE_FM) | \ FLAG64 (USE_FAbv) | \ FLAG64 (USE_FBlw) | \ FLAG64 (USE_FPst) | \ FLAG64 (USE_MAbv) | \ FLAG64 (USE_MBlw) | \ FLAG64 (USE_MPst) | \ FLAG64 (USE_MPre) | \ FLAG64 (USE_VAbv) | \ FLAG64 (USE_VBlw) | \ FLAG64 (USE_VPst) | \ FLAG64 (USE_VPre) | \ FLAG64 (USE_VMAbv) | \ FLAG64 (USE_VMBlw) | \ FLAG64 (USE_VMPst) | \ FLAG64 (USE_VMPre)) /* Move things forward. */ if (info[start].use_category() == USE_R && end - start > 1) { /* Got a repha. Reorder it towards the end, but before the first post-base * glyph. */ for (unsigned int i = start + 1; i < end; i++) { bool is_post_base_glyph = (FLAG64_UNSAFE (info[i].use_category()) & POST_BASE_FLAGS64) || is_halant (info[i]); if (is_post_base_glyph || i == end - 1) { /* If we hit a post-base glyph, move before it; otherwise move to the * end. Shift things in between backward. */ if (is_post_base_glyph) i--; buffer->merge_clusters (start, i + 1); hb_glyph_info_t t = info[start]; memmove (&info[start], &info[start + 1], (i - start) * sizeof (info[0])); info[i] = t; break; } } } /* Move things back. */ unsigned int j = start; for (unsigned int i = start; i < end; i++) { uint32_t flag = FLAG_UNSAFE (info[i].use_category()); if (is_halant (info[i])) { /* If we hit a halant, move after it; otherwise move to the beginning, and * shift things in between forward. */ j = i + 1; } else if (((flag) & (FLAG (USE_VPre) | FLAG (USE_VMPre))) && /* Only move the first component of a MultipleSubst. */ 0 == _hb_glyph_info_get_lig_comp (&info[i]) && j < i) { buffer->merge_clusters (j, i + 1); hb_glyph_info_t t = info[i]; memmove (&info[j + 1], &info[j], (i - j) * sizeof (info[0])); info[j] = t; } } } static inline void insert_dotted_circles (const hb_ot_shape_plan_t *plan HB_UNUSED, hb_font_t *font, hb_buffer_t *buffer) { if (unlikely (buffer->flags & HB_BUFFER_FLAG_DO_NOT_INSERT_DOTTED_CIRCLE)) return; /* Note: This loop is extra overhead, but should not be measurable. * TODO Use a buffer scratch flag to remove the loop. */ 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) == use_broken_cluster) { has_broken_syllables = true; break; } if (likely (!has_broken_syllables)) return; hb_glyph_info_t dottedcircle = {0}; if (!font->get_nominal_glyph (0x25CCu, &dottedcircle.codepoint)) return; dottedcircle.use_category() = hb_use_get_category (0x25CC); buffer->clear_output (); buffer->idx = 0; unsigned int last_syllable = 0; while (buffer->idx < buffer->len && buffer->successful) { unsigned int syllable = buffer->cur().syllable(); use_syllable_type_t syllable_type = (use_syllable_type_t) (syllable & 0x0F); if (unlikely (last_syllable != syllable && syllable_type == use_broken_cluster)) { last_syllable = syllable; hb_glyph_info_t ginfo = dottedcircle; ginfo.cluster = buffer->cur().cluster; ginfo.mask = buffer->cur().mask; ginfo.syllable() = buffer->cur().syllable(); /* Insert dottedcircle after possible Repha. */ while (buffer->idx < buffer->len && buffer->successful && last_syllable == buffer->cur().syllable() && buffer->cur().use_category() == USE_R) buffer->next_glyph (); buffer->output_info (ginfo); } else buffer->next_glyph (); } buffer->swap_buffers (); } static void reorder_use (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) { insert_dotted_circles (plan, font, buffer); foreach_syllable (buffer, start, end) reorder_syllable_use (buffer, start, end); HB_BUFFER_DEALLOCATE_VAR (buffer, use_category); } static void preprocess_text_use (const hb_ot_shape_plan_t *plan, hb_buffer_t *buffer, hb_font_t *font) { _hb_preprocess_text_vowel_constraints (plan, buffer, font); } static bool compose_use (const hb_ot_shape_normalize_context_t *c, hb_codepoint_t a, hb_codepoint_t b, hb_codepoint_t *ab) { /* Avoid recomposing split matras. */ if (HB_UNICODE_GENERAL_CATEGORY_IS_MARK (c->unicode->general_category (a))) return false; return (bool)c->unicode->compose (a, b, ab); } const hb_ot_complex_shaper_t _hb_ot_complex_shaper_use = { collect_features_use, nullptr, /* override_features */ data_create_use, data_destroy_use, preprocess_text_use, nullptr, /* postprocess_glyphs */ HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT, nullptr, /* decompose */ compose_use, setup_masks_use, HB_TAG_NONE, /* gpos_tag */ nullptr, /* reorder_marks */ HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY, false, /* fallback_position */ }; #endif