/* * 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-unicode-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'), }; static hb_tag_t vertical_features[] = { HB_TAG('v','e','r','t'), }; 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_global_bool_feature (HB_TAG ('l','t','r','a')); map->add_global_bool_feature (HB_TAG ('l','t','r','m')); break; case HB_DIRECTION_RTL: map->add_global_bool_feature (HB_TAG ('r','t','l','a')); map->add_feature (HB_TAG ('r','t','l','m'), 1, F_NONE); break; case HB_DIRECTION_TTB: case HB_DIRECTION_BTT: case HB_DIRECTION_INVALID: default: break; } map->add_feature (HB_TAG ('f','r','a','c'), 1, F_NONE); map->add_feature (HB_TAG ('n','u','m','r'), 1, F_NONE); map->add_feature (HB_TAG ('d','n','o','m'), 1, F_NONE); if (planner->shaper->collect_features) planner->shaper->collect_features (planner); for (unsigned int i = 0; i < ARRAY_LENGTH (common_features); i++) map->add_global_bool_feature (common_features[i]); if (HB_DIRECTION_IS_HORIZONTAL (props->direction)) for (unsigned int i = 0; i < ARRAY_LENGTH (horizontal_features); i++) map->add_feature (horizontal_features[i], 1, F_GLOBAL | (horizontal_features[i] == HB_TAG('k','e','r','n') ? F_HAS_FALLBACK : F_NONE)); else for (unsigned int i = 0; i < ARRAY_LENGTH (vertical_features); i++) map->add_feature (vertical_features[i], 1, F_GLOBAL | (vertical_features[i] == HB_TAG('v','k','r','n') ? F_HAS_FALLBACK : F_NONE)); if (planner->shaper->override_features) planner->shaper->override_features (planner); 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) ? F_GLOBAL : F_NONE); } } /* * 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 (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; if (!font->has_glyph (0x25CCu)) return; hb_glyph_info_t dottedcircle; dottedcircle.codepoint = 0x25CCu; _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_buffer_t *buffer = c->buffer; hb_unicode_funcs_t *unicode = buffer->unicode; hb_mask_t rtlm_mask = c->plan->rtlm_mask; unsigned int count = buffer->len; hb_glyph_info_t *info = buffer->info; for (unsigned int i = 0; i < count; i++) { hb_codepoint_t codepoint = unicode->mirroring (info[i].codepoint); if (likely (codepoint == info[i].codepoint)) info[i].mask |= rtlm_mask; else info[i].codepoint = codepoint; } } static inline void hb_ot_shape_setup_masks_fraction (hb_ot_shape_context_t *c) { if (!c->plan->has_frac) return; hb_buffer_t *buffer = c->buffer; /* TODO look in pre/post context text also. */ unsigned int count = buffer->len; hb_glyph_info_t *info = buffer->info; for (unsigned int i = 0; i < count; i++) { if (info[i].codepoint == 0x2044u) /* FRACTION SLASH */ { unsigned int start = i, end = i + 1; while (start && _hb_glyph_info_get_general_category (&info[start - 1]) == HB_UNICODE_GENERAL_CATEGORY_DECIMAL_NUMBER) start--; while (end < count && _hb_glyph_info_get_general_category (&info[end]) == HB_UNICODE_GENERAL_CATEGORY_DECIMAL_NUMBER) end++; for (unsigned int j = start; j < i; j++) info[j].mask |= c->plan->numr_mask | c->plan->frac_mask; info[i].mask |= c->plan->frac_mask; for (unsigned int j = i + 1; j < end; j++) info[j].mask |= c->plan->frac_mask | c->plan->dnom_mask; i = end - 1; } } } static inline void hb_ot_shape_initialize_masks (hb_ot_shape_context_t *c) { hb_ot_map_t *map = &c->plan->map; hb_buffer_t *buffer = c->buffer; hb_mask_t global_mask = map->get_global_mask (); buffer->reset_masks (global_mask); } static inline void hb_ot_shape_setup_masks (hb_ot_shape_context_t *c) { hb_ot_map_t *map = &c->plan->map; hb_buffer_t *buffer = c->buffer; hb_ot_shape_setup_masks_fraction (c); if (c->plan->shaper->setup_masks) c->plan->shaper->setup_masks (c->plan, 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); 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; hb_glyph_info_t *info = c->buffer->info; for (unsigned int i = 0; i < count; i++) { hb_ot_layout_glyph_class_mask_t klass; klass = _hb_glyph_info_get_general_category (&info[i]) != HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK ? HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH : HB_OT_LAYOUT_GLYPH_PROPS_MARK; _hb_glyph_info_set_glyph_props (&info[i], klass); } } static inline void hb_ot_substitute_default (hb_ot_shape_context_t *c) { hb_buffer_t *buffer = c->buffer; if (c->plan->shaper->preprocess_text) c->plan->shaper->preprocess_text (c->plan, buffer, c->font); hb_ot_shape_initialize_masks (c); hb_ot_mirror_chars (c); HB_BUFFER_ALLOCATE_VAR (buffer, glyph_index); _hb_ot_shape_normalize (c->plan, 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, buffer); hb_ot_map_glyphs_fast (buffer); HB_BUFFER_DEALLOCATE_VAR (buffer, glyph_index); } static inline void hb_ot_substitute_complex (hb_ot_shape_context_t *c) { hb_buffer_t *buffer = c->buffer; hb_ot_layout_substitute_start (c->font, buffer); if (!hb_ot_layout_has_glyph_classes (c->face)) hb_synthesize_glyph_classes (c); c->plan->substitute (c->font, buffer); hb_ot_layout_substitute_finish (c->font, 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 adjust_mark_offsets (hb_glyph_position_t *pos) { pos->x_offset -= pos->x_advance; pos->y_offset -= pos->y_advance; } static inline void zero_mark_width (hb_glyph_position_t *pos) { pos->x_advance = 0; pos->y_advance = 0; } static inline void zero_mark_widths_by_unicode (hb_buffer_t *buffer, bool adjust_offsets) { unsigned int count = buffer->len; for (unsigned int i = 0; i < count; i++) if (_hb_glyph_info_get_general_category (&buffer->info[i]) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) { if (adjust_offsets) adjust_mark_offsets (&buffer->pos[i]); zero_mark_width (&buffer->pos[i]); } } static inline void zero_mark_widths_by_gdef (hb_buffer_t *buffer, bool adjust_offsets) { unsigned int count = buffer->len; for (unsigned int i = 0; i < count; i++) if (_hb_glyph_info_is_mark (&buffer->info[i])) { if (adjust_offsets) adjust_mark_offsets (&buffer->pos[i]); zero_mark_width (&buffer->pos[i]); } } static inline void hb_ot_position_default (hb_ot_shape_context_t *c) { hb_direction_t direction = c->buffer->props.direction; unsigned int count = c->buffer->len; hb_glyph_info_t *info = c->buffer->info; hb_glyph_position_t *pos = c->buffer->pos; for (unsigned int i = 0; i < count; i++) { c->font->get_glyph_advance_for_direction (info[i].codepoint, direction, &pos[i].x_advance, &pos[i].y_advance); c->font->subtract_glyph_origin_for_direction (info[i].codepoint, direction, &pos[i].x_offset, &pos[i].y_offset); } } static inline bool hb_ot_position_complex (hb_ot_shape_context_t *c) { bool ret = false; unsigned int count = c->buffer->len; bool has_positioning = hb_ot_layout_has_positioning (c->face); /* If the font has no GPOS, AND, no fallback positioning will * happen, AND, direction is forward, then when zeroing mark * widths, we shift the mark with it, such that the mark * is positioned hanging over the previous glyph. When * direction is backward we don't shift and it will end up * hanging over the next glyph after the final reordering. * If fallback positinoing happens or GPOS is present, we don't * care. */ bool adjust_offsets_when_zeroing = !(has_positioning || c->plan->shaper->fallback_position || HB_DIRECTION_IS_BACKWARD (c->buffer->props.direction)); switch (c->plan->shaper->zero_width_marks) { case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY: zero_mark_widths_by_gdef (c->buffer, adjust_offsets_when_zeroing); break; /* Not currently used for any shaper: case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_UNICODE_EARLY: zero_mark_widths_by_unicode (c->buffer, adjust_offsets_when_zeroing); break; */ default: case HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE: case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_UNICODE_LATE: case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE: break; } if (has_positioning) { hb_glyph_info_t *info = c->buffer->info; hb_glyph_position_t *pos = c->buffer->pos; /* Change glyph origin to what GPOS expects, apply GPOS, change it back. */ for (unsigned int i = 0; i < count; i++) { c->font->add_glyph_origin_for_direction (info[i].codepoint, HB_DIRECTION_LTR, &pos[i].x_offset, &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 (info[i].codepoint, HB_DIRECTION_LTR, &pos[i].x_offset, &pos[i].y_offset); } ret = true; } switch (c->plan->shaper->zero_width_marks) { case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_UNICODE_LATE: zero_mark_widths_by_unicode (c->buffer, adjust_offsets_when_zeroing); break; case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE: zero_mark_widths_by_gdef (c->buffer, adjust_offsets_when_zeroing); break; default: case HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE: //case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_UNICODE_EARLY: case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY: break; } return ret; } static inline void hb_ot_position (hb_ot_shape_context_t *c) { hb_ot_layout_position_start (c->font, c->buffer); hb_ot_position_default (c); hb_bool_t fallback = !hb_ot_position_complex (c); hb_ot_layout_position_finish (c->font, c->buffer); 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_shape_fallback_kern (c->plan, c->font, c->buffer); } /* 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; enum { SPACE_DONT_KNOW, SPACE_AVAILABLE, SPACE_UNAVAILABLE } space_status = SPACE_DONT_KNOW; unsigned int count = c->buffer->len; hb_glyph_info_t *info = c->buffer->info; hb_glyph_position_t *pos = c->buffer->pos; unsigned int j = 0; for (unsigned int i = 0; i < count; i++) { if (unlikely (!_hb_glyph_info_ligated (&info[i]) && _hb_glyph_info_is_default_ignorable (&info[i]))) { if (space_status == SPACE_DONT_KNOW) space_status = c->font->get_glyph (' ', 0, &space) ? SPACE_AVAILABLE : SPACE_UNAVAILABLE; if (space_status == SPACE_AVAILABLE) { info[i].codepoint = space; pos[i].x_advance = 0; pos[i].y_advance = 0; } else continue; /* Delete it. */ } if (j != i) { info[j] = info[i]; pos[j] = pos[i]; } j++; } c->buffer->len = j; } /* 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_unicode_vars (c->buffer); 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_unicode_vars (c->buffer); 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; 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); }