/* * Copyright © 2018 Adobe 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. * * Adobe Author(s): Michiharu Ariza */ #include "hb.hh" #ifndef HB_NO_SUBSET_CFF #include "hb-ot-cff-common.hh" #include "hb-ot-cff2-table.hh" #include "hb-subset-cff-common.hh" /* Disable FDSelect format 0 for compatibility with fonttools which doesn't seem choose it. * Rarely any/much smaller than format 3 anyway. */ #define CFF_SERIALIZE_FDSELECT_0 0 using namespace CFF; /* Determine an optimal FDSelect format according to a provided plan. * * Return value: FDSelect format, size, and ranges for the most compact subset FDSelect * along with a font index remapping table */ bool hb_plan_subset_cff_fdselect (const hb_subset_plan_t *plan, unsigned int fdCount, const FDSelect &src, /* IN */ unsigned int &subset_fd_count /* OUT */, unsigned int &subset_fdselect_size /* OUT */, unsigned int &subset_fdselect_format /* OUT */, hb_vector_t &fdselect_ranges /* OUT */, hb_inc_bimap_t &fdmap /* OUT */) { subset_fd_count = 0; subset_fdselect_size = 0; subset_fdselect_format = 0; unsigned int num_ranges = 0; unsigned int subset_num_glyphs = plan->num_output_glyphs (); if (subset_num_glyphs == 0) return true; { /* use hb_set to determine the subset of font dicts */ hb_set_t *set = hb_set_create (); if (unlikely (set == &Null (hb_set_t))) return false; hb_codepoint_t prev_fd = CFF_UNDEF_CODE; for (hb_codepoint_t i = 0; i < subset_num_glyphs; i++) { hb_codepoint_t glyph; hb_codepoint_t fd; if (!plan->old_gid_for_new_gid (i, &glyph)) { /* fonttools retains FDSelect & font dicts for missing glyphs. do the same */ glyph = i; } fd = src.get_fd (glyph); set->add (fd); if (fd != prev_fd) { num_ranges++; prev_fd = fd; code_pair_t pair = { fd, i }; fdselect_ranges.push (pair); } } subset_fd_count = set->get_population (); if (subset_fd_count == fdCount) { /* all font dicts belong to the subset. no need to subset FDSelect & FDArray */ fdmap.identity (fdCount); hb_set_destroy (set); } else { /* create a fdmap */ fdmap.reset (); hb_codepoint_t fd = CFF_UNDEF_CODE; while (set->next (&fd)) fdmap.add (fd); hb_set_destroy (set); if (unlikely (fdmap.get_population () != subset_fd_count)) return false; } /* update each font dict index stored as "code" in fdselect_ranges */ for (unsigned int i = 0; i < fdselect_ranges.length; i++) fdselect_ranges[i].code = fdmap[fdselect_ranges[i].code]; } /* determine which FDSelect format is most compact */ if (subset_fd_count > 0xFF) { if (unlikely (src.format != 4)) return false; subset_fdselect_format = 4; subset_fdselect_size = FDSelect::min_size + FDSelect4::min_size + FDSelect4_Range::static_size * num_ranges + HBUINT32::static_size; } else { #if CFF_SERIALIZE_FDSELECT_0 unsigned int format0_size = FDSelect::min_size + FDSelect0::min_size + HBUINT8::static_size * subset_num_glyphs; #endif unsigned int format3_size = FDSelect::min_size + FDSelect3::min_size + FDSelect3_Range::static_size * num_ranges + HBUINT16::static_size; #if CFF_SERIALIZE_FDSELECT_0 if (format0_size <= format3_size) { // subset_fdselect_format = 0; subset_fdselect_size = format0_size; } else #endif { subset_fdselect_format = 3; subset_fdselect_size = format3_size; } } return true; } template static inline bool serialize_fdselect_3_4 (hb_serialize_context_t *c, const unsigned int num_glyphs, const FDSelect &src, unsigned int size, const hb_vector_t &fdselect_ranges) { TRACE_SERIALIZE (this); FDSELECT3_4 *p = c->allocate_size (size); if (unlikely (!p)) return_trace (false); p->nRanges () = fdselect_ranges.length; for (unsigned int i = 0; i < fdselect_ranges.length; i++) { p->ranges[i].first = fdselect_ranges[i].glyph; p->ranges[i].fd = fdselect_ranges[i].code; } p->sentinel () = num_glyphs; return_trace (true); } /* Serialize a subset FDSelect format planned above. */ bool hb_serialize_cff_fdselect (hb_serialize_context_t *c, const unsigned int num_glyphs, const FDSelect &src, unsigned int fd_count, unsigned int fdselect_format, unsigned int size, const hb_vector_t &fdselect_ranges) { TRACE_SERIALIZE (this); FDSelect *p = c->allocate_min (); if (unlikely (!p)) return_trace (false); p->format = fdselect_format; size -= FDSelect::min_size; switch (fdselect_format) { #if CFF_SERIALIZE_FDSELECT_0 case 0: { FDSelect0 *p = c->allocate_size (size); if (unlikely (!p)) return_trace (false); unsigned int range_index = 0; unsigned int fd = fdselect_ranges[range_index++].code; for (unsigned int i = 0; i < num_glyphs; i++) { if ((range_index < fdselect_ranges.len) && (i >= fdselect_ranges[range_index].glyph)) { fd = fdselect_ranges[range_index++].code; } p->fds[i] = fd; } return_trace (true); } #endif /* CFF_SERIALIZE_FDSELECT_0 */ case 3: return serialize_fdselect_3_4 (c, num_glyphs, src, size, fdselect_ranges); case 4: return serialize_fdselect_3_4 (c, num_glyphs, src, size, fdselect_ranges); default: return_trace (false); } } #endif