#ifndef OT_GLYF_GLYF_HH #define OT_GLYF_GLYF_HH #include "hb-open-type.hh" #include "hb-ot-head-table.hh" #include "hb-ot-hmtx-table.hh" #include "hb-ot-var-gvar-table.hh" #include "hb-draw.hh" #include "OT/glyf/Glyph.hh" #include "OT/glyf/loca.hh" namespace OT { /* * glyf -- TrueType Glyph Data * https://docs.microsoft.com/en-us/typography/opentype/spec/glyf */ #define HB_OT_TAG_glyf HB_TAG('g','l','y','f') struct glyf { friend struct glyf_accelerator_t; static constexpr hb_tag_t tableTag = HB_OT_TAG_glyf; bool sanitize (hb_sanitize_context_t *c HB_UNUSED) const { TRACE_SANITIZE (this); /* Runtime checks as eager sanitizing each glyph is costy */ return_trace (true); } template static bool _add_loca_and_head (hb_subset_plan_t * plan, Iterator padded_offsets, bool use_short_loca) { unsigned num_offsets = padded_offsets.len () + 1; unsigned entry_size = use_short_loca ? 2 : 4; char *loca_prime_data = (char *) hb_calloc (entry_size, num_offsets); if (unlikely (!loca_prime_data)) return false; DEBUG_MSG (SUBSET, nullptr, "loca entry_size %d num_offsets %d size %d", entry_size, num_offsets, entry_size * num_offsets); if (use_short_loca) _write_loca (padded_offsets, true, hb_array ((HBUINT16 *) loca_prime_data, num_offsets)); else _write_loca (padded_offsets, false, hb_array ((HBUINT32 *) loca_prime_data, num_offsets)); hb_blob_t *loca_blob = hb_blob_create (loca_prime_data, entry_size * num_offsets, HB_MEMORY_MODE_WRITABLE, loca_prime_data, hb_free); bool result = plan->add_table (HB_OT_TAG_loca, loca_blob) && _add_head_and_set_loca_version (plan, use_short_loca); hb_blob_destroy (loca_blob); return result; } template static void _write_loca (IteratorIn it, bool short_offsets, IteratorOut dest) { unsigned right_shift = short_offsets ? 1 : 0; unsigned int offset = 0; dest << 0; + it | hb_map ([=, &offset] (unsigned int padded_size) { offset += padded_size; DEBUG_MSG (SUBSET, nullptr, "loca entry offset %d", offset); return offset >> right_shift; }) | hb_sink (dest) ; } /* requires source of SubsetGlyph complains the identifier isn't declared */ template bool serialize (hb_serialize_context_t *c, Iterator it, bool use_short_loca, const hb_subset_plan_t *plan) { TRACE_SERIALIZE (this); unsigned init_len = c->length (); for (const auto &_ : it) _.serialize (c, use_short_loca, plan); /* As a special case when all glyph in the font are empty, add a zero byte * to the table, so that OTS doesn’t reject it, and to make the table work * on Windows as well. * See https://github.com/khaledhosny/ots/issues/52 */ if (init_len == c->length ()) { HBUINT8 empty_byte; empty_byte = 0; c->copy (empty_byte); } return_trace (true); } /* Byte region(s) per glyph to output unpadded, hints removed if so requested If we fail to process a glyph we produce an empty (0-length) glyph */ bool subset (hb_subset_context_t *c) const { TRACE_SUBSET (this); glyf *glyf_prime = c->serializer->start_embed (); if (unlikely (!c->serializer->check_success (glyf_prime))) return_trace (false); hb_vector_t glyphs; _populate_subset_glyphs (c->plan, &glyphs); auto padded_offsets = + hb_iter (glyphs) | hb_map (&SubsetGlyph::padded_size) ; unsigned max_offset = + padded_offsets | hb_reduce (hb_add, 0); bool use_short_loca = max_offset < 0x1FFFF; glyf_prime->serialize (c->serializer, hb_iter (glyphs), use_short_loca, c->plan); if (!use_short_loca) { padded_offsets = + hb_iter (glyphs) | hb_map (&SubsetGlyph::length) ; } if (unlikely (c->serializer->in_error ())) return_trace (false); return_trace (c->serializer->check_success (_add_loca_and_head (c->plan, padded_offsets, use_short_loca))); } static bool _add_head_and_set_loca_version (hb_subset_plan_t *plan, bool use_short_loca) { hb_blob_t *head_blob = hb_sanitize_context_t ().reference_table (plan->source); hb_blob_t *head_prime_blob = hb_blob_copy_writable_or_fail (head_blob); hb_blob_destroy (head_blob); if (unlikely (!head_prime_blob)) return false; head *head_prime = (head *) hb_blob_get_data_writable (head_prime_blob, nullptr); head_prime->indexToLocFormat = use_short_loca ? 0 : 1; bool success = plan->add_table (HB_OT_TAG_head, head_prime_blob); hb_blob_destroy (head_prime_blob); return success; } struct SubsetGlyph { hb_codepoint_t new_gid; hb_codepoint_t old_gid; Glyph source_glyph; hb_bytes_t dest_start; /* region of source_glyph to copy first */ hb_bytes_t dest_end; /* region of source_glyph to copy second */ bool serialize (hb_serialize_context_t *c, bool use_short_loca, const hb_subset_plan_t *plan) const { TRACE_SERIALIZE (this); hb_bytes_t dest_glyph = dest_start.copy (c); dest_glyph = hb_bytes_t (&dest_glyph, dest_glyph.length + dest_end.copy (c).length); unsigned int pad_length = use_short_loca ? padding () : 0; DEBUG_MSG (SUBSET, nullptr, "serialize %d byte glyph, width %d pad %d", dest_glyph.length, dest_glyph.length + pad_length, pad_length); HBUINT8 pad; pad = 0; while (pad_length > 0) { c->embed (pad); pad_length--; } if (unlikely (!dest_glyph.length)) return_trace (true); /* update components gids */ for (auto &_ : Glyph (dest_glyph).get_composite_iterator ()) { hb_codepoint_t new_gid; if (plan->new_gid_for_old_gid (_.get_glyph_index (), &new_gid)) const_cast (_).set_glyph_index (new_gid); } if (plan->flags & HB_SUBSET_FLAGS_NO_HINTING) Glyph (dest_glyph).drop_hints (); if (plan->flags & HB_SUBSET_FLAGS_SET_OVERLAPS_FLAG) Glyph (dest_glyph).set_overlaps_flag (); return_trace (true); } void drop_hints_bytes () { source_glyph.drop_hints_bytes (dest_start, dest_end); } unsigned int length () const { return dest_start.length + dest_end.length; } /* pad to 2 to ensure 2-byte loca will be ok */ unsigned int padding () const { return length () % 2; } unsigned int padded_size () const { return length () + padding (); } }; void _populate_subset_glyphs (const hb_subset_plan_t *plan, hb_vector_t *glyphs /* OUT */) const; protected: UnsizedArrayOf dataZ; /* Glyphs data. */ public: DEFINE_SIZE_MIN (0); /* In reality, this is UNBOUNDED() type; but since we always * check the size externally, allow Null() object of it by * defining it _MIN instead. */ }; struct glyf_accelerator_t { glyf_accelerator_t (hb_face_t *face) { short_offset = false; num_glyphs = 0; loca_table = nullptr; glyf_table = nullptr; #ifndef HB_NO_VAR gvar = nullptr; #endif hmtx = nullptr; #ifndef HB_NO_VERTICAL vmtx = nullptr; #endif const OT::head &head = *face->table.head; if (head.indexToLocFormat > 1 || head.glyphDataFormat > 0) /* Unknown format. Leave num_glyphs=0, that takes care of disabling us. */ return; short_offset = 0 == head.indexToLocFormat; loca_table = face->table.loca.get_blob (); // Needs no destruct! glyf_table = hb_sanitize_context_t ().reference_table (face); #ifndef HB_NO_VAR gvar = face->table.gvar; #endif hmtx = face->table.hmtx; #ifndef HB_NO_VERTICAL vmtx = face->table.vmtx; #endif num_glyphs = hb_max (1u, loca_table.get_length () / (short_offset ? 2 : 4)) - 1; num_glyphs = hb_min (num_glyphs, face->get_num_glyphs ()); } ~glyf_accelerator_t () { glyf_table.destroy (); } bool has_data () const { return num_glyphs; } protected: template bool get_points (hb_font_t *font, hb_codepoint_t gid, T consumer) const { if (gid >= num_glyphs) return false; /* Making this allocfree is not that easy https://github.com/harfbuzz/harfbuzz/issues/2095 mostly because of gvar handling in VF fonts, perhaps a separate path for non-VF fonts can be considered */ contour_point_vector_t all_points; bool phantom_only = !consumer.is_consuming_contour_points (); if (unlikely (!glyph_for_gid (gid).get_points (font, *this, all_points, phantom_only))) return false; if (consumer.is_consuming_contour_points ()) { for (unsigned point_index = 0; point_index + 4 < all_points.length; ++point_index) consumer.consume_point (all_points[point_index]); consumer.points_end (); } /* Where to write phantoms, nullptr if not requested */ contour_point_t *phantoms = consumer.get_phantoms_sink (); if (phantoms) for (unsigned i = 0; i < PHANTOM_COUNT; ++i) phantoms[i] = all_points[all_points.length - PHANTOM_COUNT + i]; return true; } #ifndef HB_NO_VAR struct points_aggregator_t { hb_font_t *font; hb_glyph_extents_t *extents; contour_point_t *phantoms; struct contour_bounds_t { contour_bounds_t () { min_x = min_y = FLT_MAX; max_x = max_y = -FLT_MAX; } void add (const contour_point_t &p) { min_x = hb_min (min_x, p.x); min_y = hb_min (min_y, p.y); max_x = hb_max (max_x, p.x); max_y = hb_max (max_y, p.y); } bool empty () const { return (min_x >= max_x) || (min_y >= max_y); } void get_extents (hb_font_t *font, hb_glyph_extents_t *extents) { if (unlikely (empty ())) { extents->width = 0; extents->x_bearing = 0; extents->height = 0; extents->y_bearing = 0; return; } extents->x_bearing = font->em_scalef_x (min_x); extents->width = font->em_scalef_x (max_x) - extents->x_bearing; extents->y_bearing = font->em_scalef_y (max_y); extents->height = font->em_scalef_y (min_y) - extents->y_bearing; } protected: float min_x, min_y, max_x, max_y; } bounds; points_aggregator_t (hb_font_t *font_, hb_glyph_extents_t *extents_, contour_point_t *phantoms_) { font = font_; extents = extents_; phantoms = phantoms_; if (extents) bounds = contour_bounds_t (); } void consume_point (const contour_point_t &point) { bounds.add (point); } void points_end () { bounds.get_extents (font, extents); } bool is_consuming_contour_points () { return extents; } contour_point_t *get_phantoms_sink () { return phantoms; } }; public: unsigned get_advance_var (hb_font_t *font, hb_codepoint_t gid, bool is_vertical) const { if (unlikely (gid >= num_glyphs)) return 0; bool success = false; contour_point_t phantoms[PHANTOM_COUNT]; if (likely (font->num_coords == gvar->get_axis_count ())) success = get_points (font, gid, points_aggregator_t (font, nullptr, phantoms)); if (unlikely (!success)) return #ifndef HB_NO_VERTICAL is_vertical ? vmtx->get_advance (gid) : #endif hmtx->get_advance (gid); float result = is_vertical ? phantoms[PHANTOM_TOP].y - phantoms[PHANTOM_BOTTOM].y : phantoms[PHANTOM_RIGHT].x - phantoms[PHANTOM_LEFT].x; return hb_clamp (roundf (result), 0.f, (float) UINT_MAX / 2); } int get_side_bearing_var (hb_font_t *font, hb_codepoint_t gid, bool is_vertical) const { if (unlikely (gid >= num_glyphs)) return 0; hb_glyph_extents_t extents; contour_point_t phantoms[PHANTOM_COUNT]; if (unlikely (!get_points (font, gid, points_aggregator_t (font, &extents, phantoms)))) return #ifndef HB_NO_VERTICAL is_vertical ? vmtx->get_side_bearing (gid) : #endif hmtx->get_side_bearing (gid); return is_vertical ? ceilf (phantoms[PHANTOM_TOP].y) - extents.y_bearing : floorf (phantoms[PHANTOM_LEFT].x); } #endif public: bool get_extents (hb_font_t *font, hb_codepoint_t gid, hb_glyph_extents_t *extents) const { if (unlikely (gid >= num_glyphs)) return false; #ifndef HB_NO_VAR if (font->num_coords && font->num_coords == gvar->get_axis_count ()) return get_points (font, gid, points_aggregator_t (font, extents, nullptr)); #endif return glyph_for_gid (gid).get_extents (font, *this, extents); } const Glyph glyph_for_gid (hb_codepoint_t gid, bool needs_padding_removal = false) const { if (unlikely (gid >= num_glyphs)) return Glyph (); unsigned int start_offset, end_offset; if (short_offset) { const HBUINT16 *offsets = (const HBUINT16 *) loca_table->dataZ.arrayZ; start_offset = 2 * offsets[gid]; end_offset = 2 * offsets[gid + 1]; } else { const HBUINT32 *offsets = (const HBUINT32 *) loca_table->dataZ.arrayZ; start_offset = offsets[gid]; end_offset = offsets[gid + 1]; } if (unlikely (start_offset > end_offset || end_offset > glyf_table.get_length ())) return Glyph (); Glyph glyph (hb_bytes_t ((const char *) this->glyf_table + start_offset, end_offset - start_offset), gid); return needs_padding_removal ? glyph.trim_padding () : glyph; } struct path_builder_t { hb_font_t *font; hb_draw_session_t *draw_session; struct optional_point_t { optional_point_t () { has_data = false; } optional_point_t (float x_, float y_) { x = x_; y = y_; has_data = true; } bool has_data; float x; float y; optional_point_t lerp (optional_point_t p, float t) { return optional_point_t (x + t * (p.x - x), y + t * (p.y - y)); } } first_oncurve, first_offcurve, last_offcurve; path_builder_t (hb_font_t *font_, hb_draw_session_t &draw_session_) { font = font_; draw_session = &draw_session_; first_oncurve = first_offcurve = last_offcurve = optional_point_t (); } /* based on https://github.com/RazrFalcon/ttf-parser/blob/4f32821/src/glyf.rs#L287 See also: * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM01/Chap1.html * https://stackoverflow.com/a/20772557 */ void consume_point (const contour_point_t &point) { bool is_on_curve = point.flag & Glyph::FLAG_ON_CURVE; optional_point_t p (point.x, point.y); if (!first_oncurve.has_data) { if (is_on_curve) { first_oncurve = p; draw_session->move_to (font->em_fscalef_x (p.x), font->em_fscalef_y (p.y)); } else { if (first_offcurve.has_data) { optional_point_t mid = first_offcurve.lerp (p, .5f); first_oncurve = mid; last_offcurve = p; draw_session->move_to (font->em_fscalef_x (mid.x), font->em_fscalef_y (mid.y)); } else first_offcurve = p; } } else { if (last_offcurve.has_data) { if (is_on_curve) { draw_session->quadratic_to (font->em_fscalef_x (last_offcurve.x), font->em_fscalef_y (last_offcurve.y), font->em_fscalef_x (p.x), font->em_fscalef_y (p.y)); last_offcurve = optional_point_t (); } else { optional_point_t mid = last_offcurve.lerp (p, .5f); draw_session->quadratic_to (font->em_fscalef_x (last_offcurve.x), font->em_fscalef_y (last_offcurve.y), font->em_fscalef_x (mid.x), font->em_fscalef_y (mid.y)); last_offcurve = p; } } else { if (is_on_curve) draw_session->line_to (font->em_fscalef_x (p.x), font->em_fscalef_y (p.y)); else last_offcurve = p; } } if (point.is_end_point) { if (first_offcurve.has_data && last_offcurve.has_data) { optional_point_t mid = last_offcurve.lerp (first_offcurve, .5f); draw_session->quadratic_to (font->em_fscalef_x (last_offcurve.x), font->em_fscalef_y (last_offcurve.y), font->em_fscalef_x (mid.x), font->em_fscalef_y (mid.y)); last_offcurve = optional_point_t (); /* now check the rest */ } if (first_offcurve.has_data && first_oncurve.has_data) draw_session->quadratic_to (font->em_fscalef_x (first_offcurve.x), font->em_fscalef_y (first_offcurve.y), font->em_fscalef_x (first_oncurve.x), font->em_fscalef_y (first_oncurve.y)); else if (last_offcurve.has_data && first_oncurve.has_data) draw_session->quadratic_to (font->em_fscalef_x (last_offcurve.x), font->em_fscalef_y (last_offcurve.y), font->em_fscalef_x (first_oncurve.x), font->em_fscalef_y (first_oncurve.y)); else if (first_oncurve.has_data) draw_session->line_to (font->em_fscalef_x (first_oncurve.x), font->em_fscalef_y (first_oncurve.y)); else if (first_offcurve.has_data) { float x = font->em_fscalef_x (first_offcurve.x), y = font->em_fscalef_x (first_offcurve.y); draw_session->move_to (x, y); draw_session->quadratic_to (x, y, x, y); } /* Getting ready for the next contour */ first_oncurve = first_offcurve = last_offcurve = optional_point_t (); draw_session->close_path (); } } void points_end () {} bool is_consuming_contour_points () { return true; } contour_point_t *get_phantoms_sink () { return nullptr; } }; bool get_path (hb_font_t *font, hb_codepoint_t gid, hb_draw_session_t &draw_session) const { return get_points (font, gid, path_builder_t (font, draw_session)); } #ifndef HB_NO_VAR const gvar_accelerator_t *gvar; #endif const hmtx_accelerator_t *hmtx; #ifndef HB_NO_VERTICAL const vmtx_accelerator_t *vmtx; #endif private: bool short_offset; unsigned int num_glyphs; hb_blob_ptr_t loca_table; hb_blob_ptr_t glyf_table; }; inline void glyf::_populate_subset_glyphs (const hb_subset_plan_t *plan, hb_vector_t *glyphs /* OUT */) const { OT::glyf_accelerator_t glyf (plan->source); + hb_range (plan->num_output_glyphs ()) | hb_map ([&] (hb_codepoint_t new_gid) { SubsetGlyph subset_glyph = {0}; subset_glyph.new_gid = new_gid; /* should never fail: all old gids should be mapped */ if (!plan->old_gid_for_new_gid (new_gid, &subset_glyph.old_gid)) return subset_glyph; if (new_gid == 0 && !(plan->flags & HB_SUBSET_FLAGS_NOTDEF_OUTLINE)) subset_glyph.source_glyph = Glyph (); else subset_glyph.source_glyph = glyf.glyph_for_gid (subset_glyph.old_gid, true); if (plan->flags & HB_SUBSET_FLAGS_NO_HINTING) subset_glyph.drop_hints_bytes (); else subset_glyph.dest_start = subset_glyph.source_glyph.get_bytes (); return subset_glyph; }) | hb_sink (glyphs) ; } } /* namespace OT */ #endif /* OT_GLYF_GLYF_HH */