diff --git a/src/hb-subset-glyf.cc b/src/hb-subset-glyf.cc index a186cdf7b..b0f44e2c9 100644 --- a/src/hb-subset-glyf.cc +++ b/src/hb-subset-glyf.cc @@ -32,7 +32,8 @@ bool _calculate_glyf_and_loca_prime_size (const OT::glyf::accelerator_t &glyf, hb_auto_array_t &glyph_ids, - unsigned int *glyf_size /* OUT */, + bool *use_short_loca, /* OUT */ + unsigned int *glyf_size, /* OUT */ unsigned int *loca_size /* OUT */) { unsigned int total = 0; @@ -51,23 +52,37 @@ _calculate_glyf_and_loca_prime_size (const OT::glyf::accelerator_t &glyf, } *glyf_size = total; - *loca_size = (count + 1) * sizeof(OT::HBUINT32); + *use_short_loca = (total <= 131070); + *loca_size = (count + 1) + * (*use_short_loca ? sizeof(OT::HBUINT16) : sizeof(OT::HBUINT32)); + + DEBUG_MSG(SUBSET, nullptr, "preparing to subset glyf: final size %d, loca size %d, using %s loca", + total, + *loca_size, + *use_short_loca ? "short" : "long"); return true; } +void +_write_loca_entry (unsigned int id, unsigned int offset, bool is_short, void *loca_prime) { + if (is_short) { + ((OT::HBUINT16*) loca_prime) [id].set (offset / 2); + } else { + ((OT::HBUINT32*) loca_prime) [id].set (offset); + } +} + bool _write_glyf_and_loca_prime (const OT::glyf::accelerator_t &glyf, const char *glyf_data, hb_auto_array_t &glyph_ids, + bool use_short_loca, int glyf_prime_size, char *glyf_prime_data /* OUT */, int loca_prime_size, char *loca_prime_data /* OUT */) { - // TODO(grieger): Handle the missing character glyf and outline. - char *glyf_prime_data_next = glyf_prime_data; - OT::HBUINT32 *loca_prime = (OT::HBUINT32*) loca_prime_data; hb_codepoint_t next_glyph = -1; hb_codepoint_t new_glyph_id = 0; @@ -81,7 +96,8 @@ _write_glyf_and_loca_prime (const OT::glyf::accelerator_t &glyf, int length = end_offset - start_offset; memcpy (glyf_prime_data_next, glyf_data + start_offset, length); - loca_prime[new_glyph_id].set(start_offset); + + _write_loca_entry (i, start_offset, use_short_loca, loca_prime_data); glyf_prime_data_next += length; new_glyph_id++; @@ -89,7 +105,7 @@ _write_glyf_and_loca_prime (const OT::glyf::accelerator_t &glyf, // Add the last loca entry which doesn't correspond to a specific glyph // but identifies the end of the last glyphs data. - loca_prime[new_glyph_id].set(end_offset); + _write_loca_entry (new_glyph_id, end_offset, use_short_loca, loca_prime_data); return true; } @@ -98,18 +114,20 @@ bool _hb_subset_glyf_and_loca (const OT::glyf::accelerator_t &glyf, const char *glyf_data, hb_auto_array_t &glyphs_to_retain, + bool *use_short_loca, hb_blob_t **glyf_prime /* OUT */, hb_blob_t **loca_prime /* OUT */) { // TODO(grieger): Sanity check writes to make sure they are in-bounds. // TODO(grieger): Sanity check allocation size for the new table. // TODO(grieger): Don't fail on bad offsets, just dump them. - // TODO(grieger): Support short loca output. unsigned int glyf_prime_size; unsigned int loca_prime_size; + if (unlikely (!_calculate_glyf_and_loca_prime_size (glyf, glyphs_to_retain, + use_short_loca, &glyf_prime_size, &loca_prime_size))) { return false; @@ -118,6 +136,7 @@ _hb_subset_glyf_and_loca (const OT::glyf::accelerator_t &glyf, char *glyf_prime_data = (char *) calloc (glyf_prime_size, 1); char *loca_prime_data = (char *) calloc (loca_prime_size, 1); if (unlikely (!_write_glyf_and_loca_prime (glyf, glyf_data, glyphs_to_retain, + *use_short_loca, glyf_prime_size, glyf_prime_data, loca_prime_size, loca_prime_data))) { free (glyf_prime_data); @@ -157,7 +176,12 @@ hb_subset_glyf_and_loca (hb_subset_plan_t *plan, OT::glyf::accelerator_t glyf; glyf.init(face); - bool result = _hb_subset_glyf_and_loca (glyf, glyf_data, plan->gids_to_retain_sorted, glyf_prime, loca_prime); + bool result = _hb_subset_glyf_and_loca (glyf, + glyf_data, + plan->gids_to_retain_sorted, + use_short_loca, + glyf_prime, + loca_prime); glyf.fini(); *use_short_loca = false;