From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- gfx/harfbuzz/src/hb-ot-shaper-khmer.cc | 387 +++++++++++++++++++++++++++++++++ 1 file changed, 387 insertions(+) create mode 100644 gfx/harfbuzz/src/hb-ot-shaper-khmer.cc (limited to 'gfx/harfbuzz/src/hb-ot-shaper-khmer.cc') diff --git a/gfx/harfbuzz/src/hb-ot-shaper-khmer.cc b/gfx/harfbuzz/src/hb-ot-shaper-khmer.cc new file mode 100644 index 0000000000..019a285102 --- /dev/null +++ b/gfx/harfbuzz/src/hb-ot-shaper-khmer.cc @@ -0,0 +1,387 @@ +/* + * Copyright © 2011,2012 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-shaper-khmer-machine.hh" +#include "hb-ot-shaper-indic.hh" +#include "hb-ot-layout.hh" + + +/* + * Khmer shaper. + */ + + +static const hb_ot_map_feature_t +khmer_features[] = +{ + /* + * Basic features. + * These features are applied all at once, before reordering, constrained + * to the syllable. + */ + {HB_TAG('p','r','e','f'), F_MANUAL_JOINERS | F_PER_SYLLABLE}, + {HB_TAG('b','l','w','f'), F_MANUAL_JOINERS | F_PER_SYLLABLE}, + {HB_TAG('a','b','v','f'), F_MANUAL_JOINERS | F_PER_SYLLABLE}, + {HB_TAG('p','s','t','f'), F_MANUAL_JOINERS | F_PER_SYLLABLE}, + {HB_TAG('c','f','a','r'), F_MANUAL_JOINERS | F_PER_SYLLABLE}, + /* + * Other features. + * These features are applied all at once after clearing syllables. + */ + {HB_TAG('p','r','e','s'), F_GLOBAL_MANUAL_JOINERS}, + {HB_TAG('a','b','v','s'), F_GLOBAL_MANUAL_JOINERS}, + {HB_TAG('b','l','w','s'), F_GLOBAL_MANUAL_JOINERS}, + {HB_TAG('p','s','t','s'), F_GLOBAL_MANUAL_JOINERS}, +}; + +/* + * Must be in the same order as the khmer_features array. + */ +enum { + KHMER_PREF, + KHMER_BLWF, + KHMER_ABVF, + KHMER_PSTF, + KHMER_CFAR, + + _KHMER_PRES, + _KHMER_ABVS, + _KHMER_BLWS, + _KHMER_PSTS, + + KHMER_NUM_FEATURES, + KHMER_BASIC_FEATURES = _KHMER_PRES, /* Don't forget to update this! */ +}; + +static inline void +set_khmer_properties (hb_glyph_info_t &info) +{ + hb_codepoint_t u = info.codepoint; + unsigned int type = hb_indic_get_categories (u); + + info.khmer_category() = (khmer_category_t) (type & 0xFFu); +} + +static bool +setup_syllables_khmer (const hb_ot_shape_plan_t *plan, + hb_font_t *font, + hb_buffer_t *buffer); +static bool +reorder_khmer (const hb_ot_shape_plan_t *plan, + hb_font_t *font, + hb_buffer_t *buffer); + +static void +collect_features_khmer (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_khmer); + map->add_gsub_pause (reorder_khmer); + + /* Testing suggests that Uniscribe does NOT pause between basic + * features. Test with KhmerUI.ttf and the following three + * sequences: + * + * U+1789,U+17BC + * U+1789,U+17D2,U+1789 + * U+1789,U+17D2,U+1789,U+17BC + * + * https://github.com/harfbuzz/harfbuzz/issues/974 + */ + map->enable_feature (HB_TAG('l','o','c','l'), F_PER_SYLLABLE); + map->enable_feature (HB_TAG('c','c','m','p'), F_PER_SYLLABLE); + + unsigned int i = 0; + for (; i < KHMER_BASIC_FEATURES; i++) + map->add_feature (khmer_features[i]); + + /* https://github.com/harfbuzz/harfbuzz/issues/3531 */ + map->add_gsub_pause (hb_syllabic_clear_var); // Don't need syllables anymore, use stop to free buffer var + + for (; i < KHMER_NUM_FEATURES; i++) + map->add_feature (khmer_features[i]); +} + +static void +override_features_khmer (hb_ot_shape_planner_t *plan) +{ + hb_ot_map_builder_t *map = &plan->map; + + /* Khmer spec has 'clig' as part of required shaping features: + * "Apply feature 'clig' to form ligatures that are desired for + * typographical correctness.", hence in overrides... */ + map->enable_feature (HB_TAG('c','l','i','g')); + + /* Uniscribe does not apply 'kern' in Khmer. */ + if (hb_options ().uniscribe_bug_compatible) + { + map->disable_feature (HB_TAG('k','e','r','n')); + } + + map->disable_feature (HB_TAG('l','i','g','a')); +} + + +struct khmer_shape_plan_t +{ + hb_mask_t mask_array[KHMER_NUM_FEATURES]; +}; + +static void * +data_create_khmer (const hb_ot_shape_plan_t *plan) +{ + khmer_shape_plan_t *khmer_plan = (khmer_shape_plan_t *) hb_calloc (1, sizeof (khmer_shape_plan_t)); + if (unlikely (!khmer_plan)) + return nullptr; + + for (unsigned int i = 0; i < ARRAY_LENGTH (khmer_plan->mask_array); i++) + khmer_plan->mask_array[i] = (khmer_features[i].flags & F_GLOBAL) ? + 0 : plan->map.get_1_mask (khmer_features[i].tag); + + return khmer_plan; +} + +static void +data_destroy_khmer (void *data) +{ + hb_free (data); +} + +static void +setup_masks_khmer (const hb_ot_shape_plan_t *plan HB_UNUSED, + hb_buffer_t *buffer, + hb_font_t *font HB_UNUSED) +{ + HB_BUFFER_ALLOCATE_VAR (buffer, khmer_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++) + set_khmer_properties (info[i]); +} + +static bool +setup_syllables_khmer (const hb_ot_shape_plan_t *plan HB_UNUSED, + hb_font_t *font HB_UNUSED, + hb_buffer_t *buffer) +{ + HB_BUFFER_ALLOCATE_VAR (buffer, syllable); + find_syllables_khmer (buffer); + foreach_syllable (buffer, start, end) + buffer->unsafe_to_break (start, end); + return false; +} + + +/* Rules from: + * https://docs.microsoft.com/en-us/typography/script-development/devanagari */ + +static void +reorder_consonant_syllable (const hb_ot_shape_plan_t *plan, + hb_face_t *face HB_UNUSED, + hb_buffer_t *buffer, + unsigned int start, unsigned int end) +{ + const khmer_shape_plan_t *khmer_plan = (const khmer_shape_plan_t *) plan->data; + hb_glyph_info_t *info = buffer->info; + + /* Setup masks. */ + { + /* Post-base */ + hb_mask_t mask = khmer_plan->mask_array[KHMER_BLWF] | + khmer_plan->mask_array[KHMER_ABVF] | + khmer_plan->mask_array[KHMER_PSTF]; + for (unsigned int i = start + 1; i < end; i++) + info[i].mask |= mask; + } + + unsigned int num_coengs = 0; + for (unsigned int i = start + 1; i < end; i++) + { + /* """ + * When a COENG + (Cons | IndV) combination are found (and subscript count + * is less than two) the character combination is handled according to the + * subscript type of the character following the COENG. + * + * ... + * + * Subscript Type 2 - The COENG + RO characters are reordered to immediately + * before the base glyph. Then the COENG + RO characters are assigned to have + * the 'pref' OpenType feature applied to them. + * """ + */ + if (info[i].khmer_category() == K_Cat(H) && num_coengs <= 2 && i + 1 < end) + { + num_coengs++; + + if (info[i + 1].khmer_category() == K_Cat(Ra)) + { + for (unsigned int j = 0; j < 2; j++) + info[i + j].mask |= khmer_plan->mask_array[KHMER_PREF]; + + /* Move the Coeng,Ro sequence to the start. */ + buffer->merge_clusters (start, i + 2); + hb_glyph_info_t t0 = info[i]; + hb_glyph_info_t t1 = info[i + 1]; + memmove (&info[start + 2], &info[start], (i - start) * sizeof (info[0])); + info[start] = t0; + info[start + 1] = t1; + + /* Mark the subsequent stuff with 'cfar'. Used in Khmer. + * Read the feature spec. + * This allows distinguishing the following cases with MS Khmer fonts: + * U+1784,U+17D2,U+179A,U+17D2,U+1782 + * U+1784,U+17D2,U+1782,U+17D2,U+179A + */ + if (khmer_plan->mask_array[KHMER_CFAR]) + for (unsigned int j = i + 2; j < end; j++) + info[j].mask |= khmer_plan->mask_array[KHMER_CFAR]; + + num_coengs = 2; /* Done. */ + } + } + + /* Reorder left matra piece. */ + else if (info[i].khmer_category() == K_Cat(VPre)) + { + /* Move to the start. */ + buffer->merge_clusters (start, i + 1); + hb_glyph_info_t t = info[i]; + memmove (&info[start + 1], &info[start], (i - start) * sizeof (info[0])); + info[start] = t; + } + } +} + +static void +reorder_syllable_khmer (const hb_ot_shape_plan_t *plan, + hb_face_t *face, + hb_buffer_t *buffer, + unsigned int start, unsigned int end) +{ + khmer_syllable_type_t syllable_type = (khmer_syllable_type_t) (buffer->info[start].syllable() & 0x0F); + switch (syllable_type) + { + case khmer_broken_cluster: /* We already inserted dotted-circles, so just call the consonant_syllable. */ + case khmer_consonant_syllable: + reorder_consonant_syllable (plan, face, buffer, start, end); + break; + + case khmer_non_khmer_cluster: + break; + } +} + +static bool +reorder_khmer (const hb_ot_shape_plan_t *plan, + hb_font_t *font, + hb_buffer_t *buffer) +{ + bool ret = false; + if (buffer->message (font, "start reordering khmer")) + { + if (hb_syllabic_insert_dotted_circles (font, buffer, + khmer_broken_cluster, + K_Cat(DOTTEDCIRCLE), + (unsigned) -1)) + ret = true; + + foreach_syllable (buffer, start, end) + reorder_syllable_khmer (plan, font->face, buffer, start, end); + (void) buffer->message (font, "end reordering khmer"); + } + HB_BUFFER_DEALLOCATE_VAR (buffer, khmer_category); + + return ret; +} + + +static bool +decompose_khmer (const hb_ot_shape_normalize_context_t *c, + hb_codepoint_t ab, + hb_codepoint_t *a, + hb_codepoint_t *b) +{ + switch (ab) + { + /* + * Decompose split matras that don't have Unicode decompositions. + */ + + /* Khmer */ + case 0x17BEu : *a = 0x17C1u; *b= 0x17BEu; return true; + case 0x17BFu : *a = 0x17C1u; *b= 0x17BFu; return true; + case 0x17C0u : *a = 0x17C1u; *b= 0x17C0u; return true; + case 0x17C4u : *a = 0x17C1u; *b= 0x17C4u; return true; + case 0x17C5u : *a = 0x17C1u; *b= 0x17C5u; return true; + } + + return (bool) c->unicode->decompose (ab, a, b); +} + +static bool +compose_khmer (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_shaper_t _hb_ot_shaper_khmer = +{ + collect_features_khmer, + override_features_khmer, + data_create_khmer, + data_destroy_khmer, + nullptr, /* preprocess_text */ + nullptr, /* postprocess_glyphs */ + decompose_khmer, + compose_khmer, + setup_masks_khmer, + nullptr, /* reorder_marks */ + HB_TAG_NONE, /* gpos_tag */ + HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT, + HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE, + false, /* fallback_position */ +}; + + +#endif -- cgit v1.2.3