762 lines
23 KiB
C++
762 lines
23 KiB
C++
/*
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* Copyright © 2015 Google, Inc.
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* Copyright © 2019 Ebrahim Byagowi
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*
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* This is part of HarfBuzz, a text shaping library.
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*
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* Permission is hereby granted, without written agreement and without
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* license or royalty fees, to use, copy, modify, and distribute this
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* software and its documentation for any purpose, provided that the
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* above copyright notice and the following two paragraphs appear in
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* all copies of this software.
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*
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* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
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* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
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* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
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* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
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* DAMAGE.
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*
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* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
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* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
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* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
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* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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*
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* Google Author(s): Behdad Esfahbod, Garret Rieger, Roderick Sheeter
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*/
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#ifndef HB_OT_GLYF_TABLE_HH
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#define HB_OT_GLYF_TABLE_HH
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#include "hb-open-type.hh"
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#include "hb-ot-head-table.hh"
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namespace OT {
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/*
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* loca -- Index to Location
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* https://docs.microsoft.com/en-us/typography/opentype/spec/loca
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*/
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#define HB_OT_TAG_loca HB_TAG('l','o','c','a')
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struct loca
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{
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friend struct glyf;
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static constexpr hb_tag_t tableTag = HB_OT_TAG_loca;
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bool sanitize (hb_sanitize_context_t *c HB_UNUSED) const
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{
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TRACE_SANITIZE (this);
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return_trace (true);
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}
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protected:
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UnsizedArrayOf<HBUINT8>
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dataZ; /* Location data. */
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public:
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DEFINE_SIZE_MIN (0); /* In reality, this is UNBOUNDED() type; but since we always
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* check the size externally, allow Null() object of it by
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* defining it _MIN instead. */
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};
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/*
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* glyf -- TrueType Glyph Data
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* https://docs.microsoft.com/en-us/typography/opentype/spec/glyf
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*/
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#define HB_OT_TAG_glyf HB_TAG('g','l','y','f')
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struct glyf
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{
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static constexpr hb_tag_t tableTag = HB_OT_TAG_glyf;
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bool sanitize (hb_sanitize_context_t *c HB_UNUSED) const
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{
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TRACE_SANITIZE (this);
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/* We don't check for anything specific here. The users of the
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* struct do all the hard work... */
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return_trace (true);
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}
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template<typename Iterator,
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hb_requires (hb_is_source_of (Iterator, unsigned int))>
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static bool
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_add_loca_and_head (hb_subset_plan_t * plan, Iterator padded_offsets)
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{
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unsigned max_offset = + padded_offsets | hb_reduce(hb_add, 0);
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unsigned num_offsets = padded_offsets.len () + 1;
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bool use_short_loca = max_offset < 0x1FFFF;
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unsigned entry_size = use_short_loca ? 2 : 4;
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char *loca_prime_data = (char *) calloc (entry_size, num_offsets);
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if (unlikely (!loca_prime_data)) return false;
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DEBUG_MSG (SUBSET, nullptr, "loca entry_size %d num_offsets %d "
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"max_offset %d size %d",
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entry_size, num_offsets, max_offset, entry_size * num_offsets);
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if (use_short_loca)
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_write_loca (padded_offsets, 1, hb_array ((HBUINT16*) loca_prime_data, num_offsets));
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else
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_write_loca (padded_offsets, 0, hb_array ((HBUINT32*) loca_prime_data, num_offsets));
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hb_blob_t * loca_blob = hb_blob_create (loca_prime_data,
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entry_size * num_offsets,
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HB_MEMORY_MODE_WRITABLE,
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loca_prime_data,
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free);
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bool result = plan->add_table (HB_OT_TAG_loca, loca_blob)
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&& _add_head_and_set_loca_version(plan, use_short_loca);
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hb_blob_destroy (loca_blob);
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return result;
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}
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template<typename IteratorIn, typename IteratorOut,
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hb_requires (hb_is_source_of (IteratorIn, unsigned int)),
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hb_requires (hb_is_sink_of (IteratorOut, unsigned))>
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static void
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_write_loca (IteratorIn it, unsigned right_shift, IteratorOut dest)
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{
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unsigned int offset = 0;
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dest << 0;
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+ it
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| hb_map ([=, &offset] (unsigned int padded_size)
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{
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offset += padded_size;
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DEBUG_MSG (SUBSET, nullptr, "loca entry offset %d", offset);
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return offset >> right_shift;
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})
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| hb_sink (dest)
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;
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}
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// requires source of SubsetGlyph complains the identifier isn't declared
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template <typename Iterator>
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bool serialize (hb_serialize_context_t *c,
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Iterator it,
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const hb_subset_plan_t *plan)
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{
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TRACE_SERIALIZE (this);
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+ it
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| hb_apply ([=] (const SubsetGlyph& _) { _.serialize (c, plan); })
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;
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return_trace (true);
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}
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bool subset (hb_subset_context_t *c) const
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{
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TRACE_SUBSET (this);
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glyf *glyf_prime = c->serializer->start_embed <glyf> ();
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if (unlikely (!c->serializer->check_success (glyf_prime))) return_trace (false);
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// Byte region(s) per glyph to output
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// unpadded, hints removed if so requested
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// If we fail to process a glyph we produce an empty (0-length) glyph
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hb_vector_t<SubsetGlyph> glyphs;
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_populate_subset_glyphs (c->plan, &glyphs);
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glyf_prime->serialize (c->serializer, hb_iter (glyphs), c->plan);
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auto padded_offsets =
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+ hb_iter (glyphs)
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| hb_map (&SubsetGlyph::padded_size)
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;
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if (c->serializer->in_error ()) return_trace (false);
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return_trace (c->serializer->check_success (_add_loca_and_head (c->plan,
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padded_offsets)));
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}
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template <typename SubsetGlyph>
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void
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_populate_subset_glyphs (const hb_subset_plan_t * plan,
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hb_vector_t<SubsetGlyph> * glyphs /* OUT */) const
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{
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OT::glyf::accelerator_t glyf;
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glyf.init (plan->source);
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+ hb_range (plan->num_output_glyphs ())
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| hb_map ([&] (hb_codepoint_t new_gid)
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{
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SubsetGlyph subset_glyph = {0};
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subset_glyph.new_gid = new_gid;
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// should never fail: all old gids should be mapped
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if (!plan->old_gid_for_new_gid (new_gid, &subset_glyph.old_gid))
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return subset_glyph;
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subset_glyph.source_glyph = glyf.bytes_for_glyph ((const char *) this,
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subset_glyph.old_gid);
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if (plan->drop_hints) subset_glyph.drop_hints (glyf);
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else subset_glyph.dest_start = subset_glyph.source_glyph;
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return subset_glyph;
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})
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| hb_sink (glyphs)
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;
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glyf.fini ();
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}
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static void
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_fix_component_gids (const hb_subset_plan_t *plan,
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hb_bytes_t glyph)
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{
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OT::glyf::CompositeGlyphHeader::Iterator iterator;
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if (OT::glyf::CompositeGlyphHeader::get_iterator (&glyph,
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glyph.length,
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&iterator))
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{
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do
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{
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hb_codepoint_t new_gid;
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if (!plan->new_gid_for_old_gid (iterator.current->glyphIndex,
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&new_gid))
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continue;
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((OT::glyf::CompositeGlyphHeader *) iterator.current)->glyphIndex = new_gid;
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} while (iterator.move_to_next ());
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}
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}
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static void
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_zero_instruction_length (hb_bytes_t glyph)
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{
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auto &glyph_header = GlyphHeader::from_bytes (glyph);
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if (!glyph_header.is_simple_glyph ()) return; // only for simple glyphs
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unsigned int instruction_len_offset = glyph_header.simple_instruction_len_offset ();
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const HBUINT16 &instruction_len = StructAtOffset<HBUINT16> (&glyph,
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instruction_len_offset);
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(HBUINT16 &) instruction_len = 0;
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}
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static bool _remove_composite_instruction_flag (hb_bytes_t glyph)
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{
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auto &glyph_header = GlyphHeader::from_bytes (glyph);
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if (!glyph_header.is_composite_glyph ()) return true; // only for composites
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/* remove WE_HAVE_INSTRUCTIONS from flags in dest */
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OT::glyf::CompositeGlyphHeader::Iterator composite_it;
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if (unlikely (!OT::glyf::CompositeGlyphHeader::get_iterator (&glyph, glyph.length,
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&composite_it)))
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return false;
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const OT::glyf::CompositeGlyphHeader *composite_header;
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do
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{
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composite_header = composite_it.current;
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OT::HBUINT16 *flags = const_cast<OT::HBUINT16 *> (&composite_header->flags);
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*flags = (uint16_t) *flags & ~OT::glyf::CompositeGlyphHeader::WE_HAVE_INSTRUCTIONS;
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} while (composite_it.move_to_next ());
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return true;
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}
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static bool
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_add_head_and_set_loca_version (hb_subset_plan_t *plan, bool use_short_loca)
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{
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hb_blob_t *head_blob = hb_sanitize_context_t ().reference_table<head> (plan->source);
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hb_blob_t *head_prime_blob = hb_blob_copy_writable_or_fail (head_blob);
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hb_blob_destroy (head_blob);
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if (unlikely (!head_prime_blob))
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return false;
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head *head_prime = (head *) hb_blob_get_data_writable (head_prime_blob, nullptr);
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head_prime->indexToLocFormat = use_short_loca ? 0 : 1;
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bool success = plan->add_table (HB_OT_TAG_head, head_prime_blob);
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hb_blob_destroy (head_prime_blob);
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return success;
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}
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struct GlyphHeader
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{
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static const GlyphHeader &from_bytes (hb_bytes_t glyph_bytes)
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{
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return likely (glyph_bytes.length >= static_size)
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? StructAtOffset<GlyphHeader> (&glyph_bytes, 0) : Null (GlyphHeader);
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}
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unsigned int simple_instruction_len_offset () const
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{ return static_size + 2 * numberOfContours; }
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unsigned int simple_length (unsigned int instruction_len) const
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{ return simple_instruction_len_offset () + 2 + instruction_len; }
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bool is_composite_glyph () const { return numberOfContours < 0; }
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bool is_simple_glyph () const { return numberOfContours > 0; }
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void get_extents (hb_glyph_extents_t *extents) const
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{
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extents->x_bearing = hb_min (xMin, xMax);
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extents->y_bearing = hb_max (yMin, yMax);
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extents->width = hb_max (xMin, xMax) - extents->x_bearing;
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extents->height = hb_min (yMin, yMax) - extents->y_bearing;
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}
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bool has_data () const { return numberOfContours; }
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protected:
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HBINT16 numberOfContours;/* If the number of contours is
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* greater than or equal to zero,
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* this is a simple glyph; if negative,
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* this is a composite glyph. */
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FWORD xMin; /* Minimum x for coordinate data. */
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FWORD yMin; /* Minimum y for coordinate data. */
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FWORD xMax; /* Maximum x for coordinate data. */
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FWORD yMax; /* Maximum y for coordinate data. */
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public:
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DEFINE_SIZE_STATIC (10);
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};
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struct CompositeGlyphHeader
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{
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enum composite_glyph_flag_t
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{
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ARG_1_AND_2_ARE_WORDS = 0x0001,
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ARGS_ARE_XY_VALUES = 0x0002,
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ROUND_XY_TO_GRID = 0x0004,
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WE_HAVE_A_SCALE = 0x0008,
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MORE_COMPONENTS = 0x0020,
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WE_HAVE_AN_X_AND_Y_SCALE = 0x0040,
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WE_HAVE_A_TWO_BY_TWO = 0x0080,
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WE_HAVE_INSTRUCTIONS = 0x0100,
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USE_MY_METRICS = 0x0200,
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OVERLAP_COMPOUND = 0x0400,
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SCALED_COMPONENT_OFFSET = 0x0800,
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UNSCALED_COMPONENT_OFFSET = 0x1000
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};
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HBUINT16 flags;
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GlyphID glyphIndex;
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unsigned int get_size () const
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{
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unsigned int size = min_size;
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// arg1 and 2 are int16
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if (flags & ARG_1_AND_2_ARE_WORDS) size += 4;
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// arg1 and 2 are int8
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else size += 2;
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// One x 16 bit (scale)
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if (flags & WE_HAVE_A_SCALE) size += 2;
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// Two x 16 bit (xscale, yscale)
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else if (flags & WE_HAVE_AN_X_AND_Y_SCALE) size += 4;
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// Four x 16 bit (xscale, scale01, scale10, yscale)
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else if (flags & WE_HAVE_A_TWO_BY_TWO) size += 8;
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return size;
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}
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// TODO rewrite using new iterator framework if possible
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struct Iterator
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{
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const char *glyph_start;
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const char *glyph_end;
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const CompositeGlyphHeader *current;
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bool move_to_next ()
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{
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if (current->flags & CompositeGlyphHeader::MORE_COMPONENTS)
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{
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const CompositeGlyphHeader *possible =
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&StructAfter<CompositeGlyphHeader, CompositeGlyphHeader> (*current);
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if (!in_range (possible))
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return false;
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current = possible;
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return true;
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}
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return false;
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}
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bool in_range (const CompositeGlyphHeader *composite) const
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{
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return (const char *) composite >= glyph_start
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&& ((const char *) composite + CompositeGlyphHeader::min_size) <= glyph_end
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&& ((const char *) composite + composite->get_size ()) <= glyph_end;
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}
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};
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static bool get_iterator (const char * glyph_data,
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unsigned int length,
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CompositeGlyphHeader::Iterator *iterator /* OUT */)
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{
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auto &glyph_header = GlyphHeader::from_bytes (hb_bytes_t (glyph_data, length));
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if (!glyph_header.has_data ()) return false; /* Empty glyph; zero extents. */
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if (glyph_header.is_composite_glyph ())
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{
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const CompositeGlyphHeader *possible =
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&StructAfter<CompositeGlyphHeader, GlyphHeader> (glyph_header);
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iterator->glyph_start = glyph_data;
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iterator->glyph_end = (const char *) glyph_data + length;
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if (!iterator->in_range (possible))
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return false;
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iterator->current = possible;
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return true;
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}
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return false;
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}
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DEFINE_SIZE_MIN (4);
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};
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struct accelerator_t
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{
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void init (hb_face_t *face)
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{
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memset (this, 0, sizeof (accelerator_t));
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const OT::head &head = *face->table.head;
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if (head.indexToLocFormat > 1 || head.glyphDataFormat != 0)
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/* Unknown format. Leave num_glyphs=0, that takes care of disabling us. */
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return;
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short_offset = 0 == head.indexToLocFormat;
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loca_table = hb_sanitize_context_t ().reference_table<loca> (face);
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glyf_table = hb_sanitize_context_t ().reference_table<glyf> (face);
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num_glyphs = hb_max (1u, loca_table.get_length () / (short_offset ? 2 : 4)) - 1;
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}
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void fini ()
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{
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loca_table.destroy ();
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glyf_table.destroy ();
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}
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/*
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* Returns true if the referenced glyph is a valid glyph and a composite glyph.
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* If true is returned a pointer to the composite glyph will be written into
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* composite.
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*/
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bool get_composite (hb_codepoint_t glyph,
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CompositeGlyphHeader::Iterator *composite /* OUT */) const
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{
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if (unlikely (!num_glyphs))
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return false;
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unsigned int start_offset, end_offset;
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if (!get_offsets (glyph, &start_offset, &end_offset))
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return false; /* glyph not found */
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return CompositeGlyphHeader::get_iterator ((const char *) this->glyf_table + start_offset,
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end_offset - start_offset,
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composite);
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}
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enum simple_glyph_flag_t
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{
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FLAG_ON_CURVE = 0x01,
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FLAG_X_SHORT = 0x02,
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FLAG_Y_SHORT = 0x04,
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FLAG_REPEAT = 0x08,
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FLAG_X_SAME = 0x10,
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FLAG_Y_SAME = 0x20,
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FLAG_RESERVED1 = 0x40,
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FLAG_RESERVED2 = 0x80
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};
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/* based on FontTools _g_l_y_f.py::trim */
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bool remove_padding (unsigned int start_offset,
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unsigned int *end_offset) const
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{
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const char *glyph = ((const char *) glyf_table) + start_offset;
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unsigned int glyph_length = *end_offset - start_offset;
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auto &glyph_header = GlyphHeader::from_bytes (hb_bytes_t (glyph, glyph_length));
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if (!glyph_header.has_data ()) return true;
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const char *glyph_end = glyph + glyph_length;
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if (glyph_header.is_composite_glyph ())
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/* Trimming for composites not implemented.
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* If removing hints it falls out of that. */
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return true;
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else
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{
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/* simple glyph w/contours, possibly trimmable */
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glyph += glyph_header.simple_instruction_len_offset ();
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if (unlikely (glyph + 2 >= glyph_end)) return false;
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uint16_t nCoordinates = (uint16_t) StructAtOffset<HBUINT16> (glyph - 2, 0) + 1;
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uint16_t nInstructions = (uint16_t) StructAtOffset<HBUINT16> (glyph, 0);
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glyph += 2 + nInstructions;
|
|
if (unlikely (glyph + 2 >= glyph_end)) return false;
|
|
|
|
unsigned int coordBytes = 0;
|
|
unsigned int coordsWithFlags = 0;
|
|
while (glyph < glyph_end)
|
|
{
|
|
uint8_t flag = (uint8_t) *glyph;
|
|
glyph++;
|
|
|
|
unsigned int repeat = 1;
|
|
if (flag & FLAG_REPEAT)
|
|
{
|
|
if (glyph >= glyph_end)
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "Bad flag");
|
|
return false;
|
|
}
|
|
repeat = ((uint8_t) *glyph) + 1;
|
|
glyph++;
|
|
}
|
|
|
|
unsigned int xBytes, yBytes;
|
|
xBytes = yBytes = 0;
|
|
if (flag & FLAG_X_SHORT) xBytes = 1;
|
|
else if ((flag & FLAG_X_SAME) == 0) xBytes = 2;
|
|
|
|
if (flag & FLAG_Y_SHORT) yBytes = 1;
|
|
else if ((flag & FLAG_Y_SAME) == 0) yBytes = 2;
|
|
|
|
coordBytes += (xBytes + yBytes) * repeat;
|
|
coordsWithFlags += repeat;
|
|
if (coordsWithFlags >= nCoordinates)
|
|
break;
|
|
}
|
|
|
|
if (coordsWithFlags != nCoordinates)
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "Expect %d coords to have flags, got flags for %d",
|
|
nCoordinates, coordsWithFlags);
|
|
return false;
|
|
}
|
|
glyph += coordBytes;
|
|
|
|
if (glyph < glyph_end)
|
|
*end_offset -= glyph_end - glyph;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool get_offsets (hb_codepoint_t glyph,
|
|
unsigned int *start_offset /* OUT */,
|
|
unsigned int *end_offset /* OUT */) const
|
|
{
|
|
if (unlikely (glyph >= num_glyphs))
|
|
return false;
|
|
|
|
if (short_offset)
|
|
{
|
|
const HBUINT16 *offsets = (const HBUINT16 *) loca_table->dataZ.arrayZ;
|
|
*start_offset = 2 * offsets[glyph];
|
|
*end_offset = 2 * offsets[glyph + 1];
|
|
}
|
|
else
|
|
{
|
|
const HBUINT32 *offsets = (const HBUINT32 *) loca_table->dataZ.arrayZ;
|
|
|
|
*start_offset = offsets[glyph];
|
|
*end_offset = offsets[glyph + 1];
|
|
}
|
|
|
|
if (*start_offset > *end_offset || *end_offset > glyf_table.get_length ())
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool get_instruction_length (hb_bytes_t glyph,
|
|
unsigned int * length /* OUT */) const
|
|
{
|
|
auto &glyph_header = GlyphHeader::from_bytes (glyph);
|
|
/* Empty glyph; no instructions. */
|
|
if (!glyph_header.has_data ())
|
|
{
|
|
*length = 0;
|
|
// only 0 byte glyphs are healthy when missing GlyphHeader
|
|
return glyph.length == 0;
|
|
}
|
|
if (glyph_header.is_composite_glyph ())
|
|
{
|
|
unsigned int start = glyph.length;
|
|
unsigned int end = glyph.length;
|
|
unsigned int glyph_offset = &glyph - glyf_table;
|
|
CompositeGlyphHeader::Iterator composite_it;
|
|
if (unlikely (!CompositeGlyphHeader::get_iterator (&glyph, glyph.length,
|
|
&composite_it)))
|
|
return false;
|
|
const CompositeGlyphHeader *last;
|
|
do
|
|
{
|
|
last = composite_it.current;
|
|
} while (composite_it.move_to_next ());
|
|
|
|
if ((uint16_t) last->flags & CompositeGlyphHeader::WE_HAVE_INSTRUCTIONS)
|
|
start = ((char *) last - (char *) glyf_table->dataZ.arrayZ)
|
|
+ last->get_size () - glyph_offset;
|
|
if (unlikely (start > end))
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "Invalid instruction offset, %d is outside "
|
|
"%d byte buffer", start, glyph.length);
|
|
return false;
|
|
}
|
|
*length = end - start;
|
|
}
|
|
else
|
|
{
|
|
unsigned int instruction_len_offset = glyph_header.simple_instruction_len_offset ();
|
|
if (unlikely (instruction_len_offset + 2 > glyph.length))
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "Glyph size is too short, missing field "
|
|
"instructionLength.");
|
|
return false;
|
|
}
|
|
|
|
const HBUINT16 &instruction_len = StructAtOffset<HBUINT16> (&glyph,
|
|
instruction_len_offset);
|
|
/* Out of bounds of the current glyph */
|
|
if (unlikely (glyph_header.simple_length (instruction_len) > glyph.length))
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "The instructions array overruns the "
|
|
"glyph's boundaries.");
|
|
return false;
|
|
}
|
|
*length = (uint16_t) instruction_len;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool get_extents (hb_codepoint_t glyph, hb_glyph_extents_t *extents) const
|
|
{
|
|
unsigned int start_offset, end_offset;
|
|
if (!get_offsets (glyph, &start_offset, &end_offset))
|
|
return false;
|
|
|
|
GlyphHeader::from_bytes (hb_bytes_t ((const char *) glyf_table + start_offset,
|
|
end_offset - start_offset)).get_extents (extents);
|
|
return true;
|
|
}
|
|
|
|
hb_bytes_t bytes_for_glyph (const char *glyf, hb_codepoint_t gid)
|
|
{
|
|
unsigned int start_offset, end_offset;
|
|
if (unlikely (!(get_offsets (gid, &start_offset, &end_offset) &&
|
|
remove_padding (start_offset, &end_offset))))
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "Unable to get offset or remove padding for %d", gid);
|
|
return hb_bytes_t ();
|
|
}
|
|
hb_bytes_t glyph_bytes = hb_bytes_t (glyf + start_offset, end_offset - start_offset);
|
|
if (!GlyphHeader::from_bytes (glyph_bytes).has_data ())
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "Empty or invalid glyph size, %d", gid);
|
|
return hb_bytes_t ();
|
|
}
|
|
return glyph_bytes;
|
|
}
|
|
|
|
private:
|
|
bool short_offset;
|
|
unsigned int num_glyphs;
|
|
hb_blob_ptr_t<loca> loca_table;
|
|
hb_blob_ptr_t<glyf> glyf_table;
|
|
};
|
|
|
|
struct SubsetGlyph
|
|
{
|
|
hb_codepoint_t new_gid;
|
|
hb_codepoint_t old_gid;
|
|
hb_bytes_t 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,
|
|
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 = padding ();
|
|
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 (dest_glyph.length)
|
|
{
|
|
_fix_component_gids (plan, dest_glyph);
|
|
if (plan->drop_hints)
|
|
{
|
|
_zero_instruction_length (dest_glyph);
|
|
c->check_success (_remove_composite_instruction_flag (dest_glyph));
|
|
}
|
|
}
|
|
|
|
return_trace (true);
|
|
}
|
|
|
|
void drop_hints (const OT::glyf::accelerator_t& glyf)
|
|
{
|
|
if (source_glyph.length == 0) return;
|
|
|
|
unsigned int instruction_len = 0;
|
|
if (!glyf.get_instruction_length (source_glyph, &instruction_len))
|
|
{
|
|
DEBUG_MSG (SUBSET, nullptr, "Unable to read instruction length for new_gid %d",
|
|
new_gid);
|
|
return ;
|
|
}
|
|
|
|
const GlyphHeader& header = GlyphHeader::from_bytes (source_glyph);
|
|
DEBUG_MSG (SUBSET, nullptr, "new_gid %d drop %d instruction bytes "
|
|
"from %d byte source glyph",
|
|
new_gid, instruction_len, source_glyph.length);
|
|
if (header.is_composite_glyph ())
|
|
{
|
|
/* just chop instructions off the end for composite glyphs */
|
|
dest_start = hb_bytes_t (&source_glyph, source_glyph.length - instruction_len);
|
|
}
|
|
else
|
|
{
|
|
unsigned int glyph_length = header.simple_length (instruction_len);
|
|
dest_start = hb_bytes_t (&source_glyph, glyph_length - instruction_len);
|
|
dest_end = hb_bytes_t (&source_glyph + glyph_length,
|
|
source_glyph.length - glyph_length);
|
|
DEBUG_MSG (SUBSET, nullptr, "source_len %d start len %d glyph_len %d "
|
|
"instruction_len %d end len %d",
|
|
source_glyph.length, dest_start.length, glyph_length,
|
|
instruction_len, dest_end.length);
|
|
}
|
|
}
|
|
|
|
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 (); }
|
|
};
|
|
|
|
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 {};
|
|
|
|
} /* namespace OT */
|
|
|
|
|
|
#endif /* HB_OT_GLYF_TABLE_HH */
|