diff options
Diffstat (limited to 'thirdparty/harfbuzz/src/OT/glyf/glyf.hh')
| -rw-r--r-- | thirdparty/harfbuzz/src/OT/glyf/glyf.hh | 388 |
1 files changed, 388 insertions, 0 deletions
diff --git a/thirdparty/harfbuzz/src/OT/glyf/glyf.hh b/thirdparty/harfbuzz/src/OT/glyf/glyf.hh new file mode 100644 index 0000000000..f74513cb96 --- /dev/null +++ b/thirdparty/harfbuzz/src/OT/glyf/glyf.hh @@ -0,0 +1,388 @@ +#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 "glyf-helpers.hh" +#include "Glyph.hh" +#include "SubsetGlyph.hh" +#include "loca.hh" +#include "path-builder.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); + } + + /* requires source of SubsetGlyph complains the identifier isn't declared */ + template <typename Iterator> + 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 <glyf> (); + if (unlikely (!c->serializer->check_success (glyf_prime))) return_trace (false); + + hb_vector_t<glyf_impl::SubsetGlyph> glyphs; + _populate_subset_glyphs (c->plan, &glyphs); + + auto padded_offsets = + + hb_iter (glyphs) + | hb_map (&glyf_impl::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 (&glyf_impl::SubsetGlyph::length) + ; + } + + + if (unlikely (c->serializer->in_error ())) return_trace (false); + return_trace (c->serializer->check_success (glyf_impl::_add_loca_and_head (c->plan, + padded_offsets, + use_short_loca))); + } + + void + _populate_subset_glyphs (const hb_subset_plan_t *plan, + hb_vector_t<glyf_impl::SubsetGlyph> *glyphs /* OUT */) const; + + protected: + UnsizedArrayOf<HBUINT8> + 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<glyf> (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<typename T> + 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 ()) + { + unsigned count = all_points.length; + assert (count >= glyf_impl::PHANTOM_COUNT); + count -= glyf_impl::PHANTOM_COUNT; + for (unsigned point_index = 0; point_index < count; 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 < glyf_impl::PHANTOM_COUNT; ++i) + phantoms[i] = all_points[all_points.length - glyf_impl::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[glyf_impl::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[glyf_impl::PHANTOM_TOP].y - phantoms[glyf_impl::PHANTOM_BOTTOM].y + : phantoms[glyf_impl::PHANTOM_RIGHT].x - phantoms[glyf_impl::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[glyf_impl::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[glyf_impl::PHANTOM_TOP].y) - extents.y_bearing + : floorf (phantoms[glyf_impl::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) + return get_points (font, gid, points_aggregator_t (font, extents, nullptr)); +#endif + return glyph_for_gid (gid).get_extents (font, *this, extents); + } + + const glyf_impl::Glyph + glyph_for_gid (hb_codepoint_t gid, bool needs_padding_removal = false) const + { + if (unlikely (gid >= num_glyphs)) return glyf_impl::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 glyf_impl::Glyph (); + + glyf_impl::Glyph glyph (hb_bytes_t ((const char *) this->glyf_table + start_offset, + end_offset - start_offset), gid); + return needs_padding_removal ? glyf_impl::Glyph (glyph.trim_padding (), gid) : glyph; + } + + bool + get_path (hb_font_t *font, hb_codepoint_t gid, hb_draw_session_t &draw_session) const + { return get_points (font, gid, glyf_impl::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> loca_table; + hb_blob_ptr_t<glyf> glyf_table; +}; + + +inline void +glyf::_populate_subset_glyphs (const hb_subset_plan_t *plan, + hb_vector_t<glyf_impl::SubsetGlyph> *glyphs /* OUT */) const +{ + OT::glyf_accelerator_t glyf (plan->source); + + + hb_range (plan->num_output_glyphs ()) + | hb_map ([&] (hb_codepoint_t new_gid) + { + glyf_impl::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 = glyf_impl::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 */ |