diff options
Diffstat (limited to 'Build/source/libs/harfbuzz/harfbuzz-0.9.7/src/hb-ot-shape.cc')
| -rw-r--r-- | Build/source/libs/harfbuzz/harfbuzz-0.9.7/src/hb-ot-shape.cc | 640 |
1 files changed, 640 insertions, 0 deletions
diff --git a/Build/source/libs/harfbuzz/harfbuzz-0.9.7/src/hb-ot-shape.cc b/Build/source/libs/harfbuzz/harfbuzz-0.9.7/src/hb-ot-shape.cc new file mode 100644 index 00000000000..96461d7079e --- /dev/null +++ b/Build/source/libs/harfbuzz/harfbuzz-0.9.7/src/hb-ot-shape.cc @@ -0,0 +1,640 @@ +/* + * Copyright © 2009,2010 Red Hat, Inc. + * Copyright © 2010,2011,2012 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. + * + * Red Hat Author(s): Behdad Esfahbod + * Google Author(s): Behdad Esfahbod + */ + +#define HB_SHAPER ot +#define hb_ot_shaper_face_data_t hb_ot_layout_t +#define hb_ot_shaper_shape_plan_data_t hb_ot_shape_plan_t +#include "hb-shaper-impl-private.hh" + +#include "hb-ot-shape-private.hh" +#include "hb-ot-shape-complex-private.hh" +#include "hb-ot-shape-fallback-private.hh" +#include "hb-ot-shape-normalize-private.hh" + +#include "hb-ot-layout-private.hh" +#include "hb-set-private.hh" + + +static hb_tag_t common_features[] = { + HB_TAG('c','c','m','p'), + HB_TAG('l','i','g','a'), + HB_TAG('l','o','c','l'), + HB_TAG('m','a','r','k'), + HB_TAG('m','k','m','k'), + HB_TAG('r','l','i','g'), +}; + + +static hb_tag_t horizontal_features[] = { + HB_TAG('c','a','l','t'), + HB_TAG('c','l','i','g'), + HB_TAG('c','u','r','s'), + HB_TAG('k','e','r','n'), + HB_TAG('r','c','l','t'), +}; + +/* Note: + * Technically speaking, vrt2 and vert are mutually exclusive. + * According to the spec, valt and vpal are also mutually exclusive. + * But we apply them all for now. + */ +static hb_tag_t vertical_features[] = { + HB_TAG('v','a','l','t'), + HB_TAG('v','e','r','t'), + HB_TAG('v','k','r','n'), + HB_TAG('v','p','a','l'), + HB_TAG('v','r','t','2'), +}; + + + +static void +hb_ot_shape_collect_features (hb_ot_shape_planner_t *planner, + const hb_segment_properties_t *props, + const hb_feature_t *user_features, + unsigned int num_user_features) +{ + hb_ot_map_builder_t *map = &planner->map; + + switch (props->direction) { + case HB_DIRECTION_LTR: + map->add_bool_feature (HB_TAG ('l','t','r','a')); + map->add_bool_feature (HB_TAG ('l','t','r','m')); + break; + case HB_DIRECTION_RTL: + map->add_bool_feature (HB_TAG ('r','t','l','a')); + map->add_bool_feature (HB_TAG ('r','t','l','m'), false); + break; + case HB_DIRECTION_TTB: + case HB_DIRECTION_BTT: + case HB_DIRECTION_INVALID: + default: + break; + } + +#define ADD_FEATURES(array) \ + HB_STMT_START { \ + for (unsigned int i = 0; i < ARRAY_LENGTH (array); i++) \ + map->add_bool_feature (array[i]); \ + } HB_STMT_END + + if (planner->shaper->collect_features) + planner->shaper->collect_features (planner); + + ADD_FEATURES (common_features); + + if (HB_DIRECTION_IS_HORIZONTAL (props->direction)) + ADD_FEATURES (horizontal_features); + else + ADD_FEATURES (vertical_features); + + if (planner->shaper->override_features) + planner->shaper->override_features (planner); + +#undef ADD_FEATURES + + for (unsigned int i = 0; i < num_user_features; i++) { + const hb_feature_t *feature = &user_features[i]; + map->add_feature (feature->tag, feature->value, (feature->start == 0 && feature->end == (unsigned int) -1)); + } +} + + +/* + * shaper face data + */ + +hb_ot_shaper_face_data_t * +_hb_ot_shaper_face_data_create (hb_face_t *face) +{ + return _hb_ot_layout_create (face); +} + +void +_hb_ot_shaper_face_data_destroy (hb_ot_shaper_face_data_t *data) +{ + _hb_ot_layout_destroy (data); +} + + +/* + * shaper font data + */ + +struct hb_ot_shaper_font_data_t {}; + +hb_ot_shaper_font_data_t * +_hb_ot_shaper_font_data_create (hb_font_t *font) +{ + return (hb_ot_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED; +} + +void +_hb_ot_shaper_font_data_destroy (hb_ot_shaper_font_data_t *data) +{ +} + + +/* + * shaper shape_plan data + */ + +hb_ot_shaper_shape_plan_data_t * +_hb_ot_shaper_shape_plan_data_create (hb_shape_plan_t *shape_plan, + const hb_feature_t *user_features, + unsigned int num_user_features) +{ + hb_ot_shape_plan_t *plan = (hb_ot_shape_plan_t *) calloc (1, sizeof (hb_ot_shape_plan_t)); + if (unlikely (!plan)) + return NULL; + + hb_ot_shape_planner_t planner (shape_plan); + + planner.shaper = hb_ot_shape_complex_categorize (&planner); + + hb_ot_shape_collect_features (&planner, &shape_plan->props, user_features, num_user_features); + + planner.compile (*plan); + + if (plan->shaper->data_create) { + plan->data = plan->shaper->data_create (plan); + if (unlikely (!plan->data)) + return NULL; + } + + return plan; +} + +void +_hb_ot_shaper_shape_plan_data_destroy (hb_ot_shaper_shape_plan_data_t *plan) +{ + if (plan->shaper->data_destroy) + plan->shaper->data_destroy (const_cast<void *> (plan->data)); + + plan->finish (); + + free (plan); +} + + +/* + * shaper + */ + +struct hb_ot_shape_context_t +{ + hb_ot_shape_plan_t *plan; + hb_font_t *font; + hb_face_t *face; + hb_buffer_t *buffer; + const hb_feature_t *user_features; + unsigned int num_user_features; + + /* Transient stuff */ + hb_direction_t target_direction; +}; + + + +/* Main shaper */ + + +/* Prepare */ + +static void +hb_set_unicode_props (hb_buffer_t *buffer) +{ + unsigned int count = buffer->len; + for (unsigned int i = 0; i < count; i++) + _hb_glyph_info_set_unicode_props (&buffer->info[i], buffer->unicode); +} + +static void +hb_insert_dotted_circle (hb_buffer_t *buffer, hb_font_t *font) +{ + if (!(buffer->flags & HB_BUFFER_FLAG_BOT) || + _hb_glyph_info_get_general_category (&buffer->info[0]) != + HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) + return; + + hb_codepoint_t dottedcircle_glyph; + if (!font->get_glyph (0x25CC, 0, &dottedcircle_glyph)) + return; + + hb_glyph_info_t dottedcircle; + dottedcircle.codepoint = 0x25CC; + _hb_glyph_info_set_unicode_props (&dottedcircle, buffer->unicode); + + buffer->clear_output (); + + buffer->idx = 0; + hb_glyph_info_t info = dottedcircle; + info.cluster = buffer->cur().cluster; + info.mask = buffer->cur().mask; + buffer->output_info (info); + while (buffer->idx < buffer->len) + buffer->next_glyph (); + + buffer->swap_buffers (); +} + +static void +hb_form_clusters (hb_buffer_t *buffer) +{ + unsigned int count = buffer->len; + for (unsigned int i = 1; i < count; i++) + if (HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&buffer->info[i]))) + buffer->merge_clusters (i - 1, i + 1); +} + +static void +hb_ensure_native_direction (hb_buffer_t *buffer) +{ + hb_direction_t direction = buffer->props.direction; + + /* TODO vertical: + * The only BTT vertical script is Ogham, but it's not clear to me whether OpenType + * Ogham fonts are supposed to be implemented BTT or not. Need to research that + * first. */ + if ((HB_DIRECTION_IS_HORIZONTAL (direction) && direction != hb_script_get_horizontal_direction (buffer->props.script)) || + (HB_DIRECTION_IS_VERTICAL (direction) && direction != HB_DIRECTION_TTB)) + { + hb_buffer_reverse_clusters (buffer); + buffer->props.direction = HB_DIRECTION_REVERSE (buffer->props.direction); + } +} + + +/* Substitute */ + +static inline void +hb_ot_mirror_chars (hb_ot_shape_context_t *c) +{ + if (HB_DIRECTION_IS_FORWARD (c->target_direction)) + return; + + hb_unicode_funcs_t *unicode = c->buffer->unicode; + hb_mask_t rtlm_mask = c->plan->map.get_1_mask (HB_TAG ('r','t','l','m')); + + unsigned int count = c->buffer->len; + for (unsigned int i = 0; i < count; i++) { + hb_codepoint_t codepoint = unicode->mirroring (c->buffer->info[i].codepoint); + if (likely (codepoint == c->buffer->info[i].codepoint)) + c->buffer->info[i].mask |= rtlm_mask; + else + c->buffer->info[i].codepoint = codepoint; + } +} + +static inline void +hb_ot_shape_setup_masks (hb_ot_shape_context_t *c) +{ + hb_ot_map_t *map = &c->plan->map; + + hb_mask_t global_mask = map->get_global_mask (); + c->buffer->reset_masks (global_mask); + + if (c->plan->shaper->setup_masks) + c->plan->shaper->setup_masks (c->plan, c->buffer, c->font); + + for (unsigned int i = 0; i < c->num_user_features; i++) + { + const hb_feature_t *feature = &c->user_features[i]; + if (!(feature->start == 0 && feature->end == (unsigned int)-1)) { + unsigned int shift; + hb_mask_t mask = map->get_mask (feature->tag, &shift); + c->buffer->set_masks (feature->value << shift, mask, feature->start, feature->end); + } + } +} + +static inline void +hb_ot_map_glyphs_fast (hb_buffer_t *buffer) +{ + /* Normalization process sets up glyph_index(), we just copy it. */ + unsigned int count = buffer->len; + for (unsigned int i = 0; i < count; i++) + buffer->info[i].codepoint = buffer->info[i].glyph_index(); +} + +static inline void +hb_synthesize_glyph_classes (hb_ot_shape_context_t *c) +{ + unsigned int count = c->buffer->len; + for (unsigned int i = 0; i < count; i++) + c->buffer->info[i].glyph_props() = _hb_glyph_info_get_general_category (&c->buffer->info[i]) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK ? + HB_OT_LAYOUT_GLYPH_PROPS_MARK : + HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH; +} + +static inline void +hb_ot_substitute_default (hb_ot_shape_context_t *c) +{ + if (c->plan->shaper->preprocess_text) + c->plan->shaper->preprocess_text (c->plan, c->buffer, c->font); + + hb_ot_mirror_chars (c); + + HB_BUFFER_ALLOCATE_VAR (c->buffer, glyph_index); + + _hb_ot_shape_normalize (c->plan, c->buffer, c->font); + + hb_ot_shape_setup_masks (c); + + /* This is unfortunate to go here, but necessary... */ + if (!hb_ot_layout_has_positioning (c->face)) + _hb_ot_shape_fallback_position_recategorize_marks (c->plan, c->font, c->buffer); + + hb_ot_map_glyphs_fast (c->buffer); + + HB_BUFFER_DEALLOCATE_VAR (c->buffer, glyph_index); +} + +static inline void +hb_ot_substitute_complex (hb_ot_shape_context_t *c) +{ + hb_ot_layout_substitute_start (c->font, c->buffer); + + if (!hb_ot_layout_has_glyph_classes (c->face)) + hb_synthesize_glyph_classes (c); + + c->plan->substitute (c->font, c->buffer); + + hb_ot_layout_substitute_finish (c->font, c->buffer); + + return; +} + +static inline void +hb_ot_substitute (hb_ot_shape_context_t *c) +{ + hb_ot_substitute_default (c); + hb_ot_substitute_complex (c); +} + +/* Position */ + +static inline void +hb_ot_position_default (hb_ot_shape_context_t *c) +{ + hb_ot_layout_position_start (c->font, c->buffer); + + unsigned int count = c->buffer->len; + for (unsigned int i = 0; i < count; i++) { + c->font->get_glyph_advance_for_direction (c->buffer->info[i].codepoint, + c->buffer->props.direction, + &c->buffer->pos[i].x_advance, + &c->buffer->pos[i].y_advance); + c->font->subtract_glyph_origin_for_direction (c->buffer->info[i].codepoint, + c->buffer->props.direction, + &c->buffer->pos[i].x_offset, + &c->buffer->pos[i].y_offset); + } +} + +static inline bool +hb_ot_position_complex (hb_ot_shape_context_t *c) +{ + bool ret = false; + + if (hb_ot_layout_has_positioning (c->face)) + { + /* Change glyph origin to what GPOS expects, apply GPOS, change it back. */ + + unsigned int count = c->buffer->len; + for (unsigned int i = 0; i < count; i++) { + c->font->add_glyph_origin_for_direction (c->buffer->info[i].codepoint, + HB_DIRECTION_LTR, + &c->buffer->pos[i].x_offset, + &c->buffer->pos[i].y_offset); + } + + c->plan->position (c->font, c->buffer); + + for (unsigned int i = 0; i < count; i++) { + c->font->subtract_glyph_origin_for_direction (c->buffer->info[i].codepoint, + HB_DIRECTION_LTR, + &c->buffer->pos[i].x_offset, + &c->buffer->pos[i].y_offset); + } + + ret = true; + } + + hb_ot_layout_position_finish (c->font, c->buffer, c->plan->shaper->zero_width_attached_marks); + + return ret; +} + +static inline void +hb_ot_truetype_kern (hb_ot_shape_context_t *c) +{ + /* TODO Check for kern=0 */ + unsigned int count = c->buffer->len; + for (unsigned int i = 1; i < count; i++) { + hb_position_t x_kern, y_kern, kern1, kern2; + c->font->get_glyph_kerning_for_direction (c->buffer->info[i - 1].codepoint, c->buffer->info[i].codepoint, + c->buffer->props.direction, + &x_kern, &y_kern); + + kern1 = x_kern >> 1; + kern2 = x_kern - kern1; + c->buffer->pos[i - 1].x_advance += kern1; + c->buffer->pos[i].x_advance += kern2; + c->buffer->pos[i].x_offset += kern2; + + kern1 = y_kern >> 1; + kern2 = y_kern - kern1; + c->buffer->pos[i - 1].y_advance += kern1; + c->buffer->pos[i].y_advance += kern2; + c->buffer->pos[i].y_offset += kern2; + } +} + +static inline void +hb_ot_position (hb_ot_shape_context_t *c) +{ + hb_ot_position_default (c); + + hb_bool_t fallback = !hb_ot_position_complex (c); + + if (fallback && c->plan->shaper->fallback_position) + _hb_ot_shape_fallback_position (c->plan, c->font, c->buffer); + + if (HB_DIRECTION_IS_BACKWARD (c->buffer->props.direction)) + hb_buffer_reverse (c->buffer); + + /* Visual fallback goes here. */ + + if (fallback) + hb_ot_truetype_kern (c); +} + + +/* Post-process */ + +static void +hb_ot_hide_default_ignorables (hb_ot_shape_context_t *c) +{ + if (c->buffer->flags & HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES) + return; + + hb_codepoint_t space = 0; + + unsigned int count = c->buffer->len; + for (unsigned int i = 0; i < count; i++) + if (unlikely (!is_a_ligature (c->buffer->info[i]) && + _hb_glyph_info_is_default_ignorable (&c->buffer->info[i]))) + { + if (!space) { + /* We assume that the space glyph is not gid0. */ + if (unlikely (!c->font->get_glyph (' ', 0, &space)) || !space) + return; /* No point! */ + } + c->buffer->info[i].codepoint = space; + c->buffer->pos[i].x_advance = 0; + c->buffer->pos[i].y_advance = 0; + } +} + + +/* Pull it all together! */ + +static void +hb_ot_shape_internal (hb_ot_shape_context_t *c) +{ + c->buffer->deallocate_var_all (); + + /* Save the original direction, we use it later. */ + c->target_direction = c->buffer->props.direction; + + HB_BUFFER_ALLOCATE_VAR (c->buffer, unicode_props0); + HB_BUFFER_ALLOCATE_VAR (c->buffer, unicode_props1); + + c->buffer->clear_output (); + + hb_set_unicode_props (c->buffer); + hb_insert_dotted_circle (c->buffer, c->font); + hb_form_clusters (c->buffer); + + hb_ensure_native_direction (c->buffer); + + hb_ot_substitute (c); + hb_ot_position (c); + + hb_ot_hide_default_ignorables (c); + + HB_BUFFER_DEALLOCATE_VAR (c->buffer, unicode_props1); + HB_BUFFER_DEALLOCATE_VAR (c->buffer, unicode_props0); + + c->buffer->props.direction = c->target_direction; + + c->buffer->deallocate_var_all (); +} + + +hb_bool_t +_hb_ot_shape (hb_shape_plan_t *shape_plan, + hb_font_t *font, + hb_buffer_t *buffer, + const hb_feature_t *features, + unsigned int num_features) +{ + hb_ot_shape_context_t c = {HB_SHAPER_DATA_GET (shape_plan), font, font->face, buffer, features, num_features}; + hb_ot_shape_internal (&c); + + return true; +} + + +void +hb_ot_shape_plan_collect_lookups (hb_shape_plan_t *shape_plan, + hb_tag_t table_tag, + hb_set_t *lookup_indexes /* OUT */) +{ + /* XXX Does the first part always succeed? */ + HB_SHAPER_DATA_GET (shape_plan)->collect_lookups (table_tag, lookup_indexes); +} + + +/* TODO Move this to hb-ot-shape-normalize, make it do decompose, and make it public. */ +static void +add_char (hb_font_t *font, + hb_unicode_funcs_t *unicode, + hb_bool_t mirror, + hb_codepoint_t u, + hb_set_t *glyphs) +{ + hb_codepoint_t glyph; + if (font->get_glyph (u, 0, &glyph)) + glyphs->add (glyph); + if (mirror) + { + hb_codepoint_t m = unicode->mirroring (u); + if (m != u && font->get_glyph (m, 0, &glyph)) + glyphs->add (glyph); + } +} + + +void +hb_ot_shape_glyphs_closure (hb_font_t *font, + hb_buffer_t *buffer, + const hb_feature_t *features, + unsigned int num_features, + hb_set_t *glyphs) +{ + hb_ot_shape_plan_t plan; + + buffer->guess_segment_properties (); + + const char *shapers[] = {"ot", NULL}; + hb_shape_plan_t *shape_plan = hb_shape_plan_create_cached (font->face, &buffer->props, + features, num_features, shapers); + + bool mirror = hb_script_get_horizontal_direction (buffer->props.script) == HB_DIRECTION_RTL; + + unsigned int count = buffer->len; + for (unsigned int i = 0; i < count; i++) + add_char (font, buffer->unicode, mirror, buffer->info[i].codepoint, glyphs); + + hb_set_t lookups; + lookups.init (); + hb_ot_shape_plan_collect_lookups (shape_plan, HB_OT_TAG_GSUB, &lookups); + + /* And find transitive closure. */ + hb_set_t copy; + copy.init (); + do { + copy.set (glyphs); + for (hb_codepoint_t lookup_index = -1; hb_set_next (&lookups, &lookup_index);) + hb_ot_layout_lookup_substitute_closure (font->face, lookup_index, glyphs); + } while (!copy.is_equal (glyphs)); + + hb_shape_plan_destroy (shape_plan); +} |