1 // Copyright (c) 2009 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "ltsh.h" 6 7 #include "maxp.h" 8 9 // LTSH - Linear Threshold 10 // http://www.microsoft.com/typography/otspec/ltsh.htm 11 12 #define DROP_THIS_TABLE \ 13 do { delete file->ltsh; file->ltsh = 0; } while (0) 14 15 namespace ots { 16 17 bool ots_ltsh_parse(OpenTypeFile *file, const uint8_t *data, size_t length) { 18 Buffer table(data, length); 19 20 if (!file->maxp) { 21 return OTS_FAILURE(); 22 } 23 24 OpenTypeLTSH *ltsh = new OpenTypeLTSH; 25 file->ltsh = ltsh; 26 27 uint16_t num_glyphs = 0; 28 if (!table.ReadU16(<sh->version) || 29 !table.ReadU16(&num_glyphs)) { 30 return OTS_FAILURE(); 31 } 32 33 if (ltsh->version != 0) { 34 OTS_WARNING("bad version: %u", ltsh->version); 35 DROP_THIS_TABLE; 36 return true; 37 } 38 39 if (num_glyphs != file->maxp->num_glyphs) { 40 OTS_WARNING("bad num_glyphs: %u", num_glyphs); 41 DROP_THIS_TABLE; 42 return true; 43 } 44 45 ltsh->ypels.reserve(num_glyphs); 46 for (unsigned i = 0; i < num_glyphs; ++i) { 47 uint8_t pel = 0; 48 if (!table.ReadU8(&pel)) { 49 return OTS_FAILURE(); 50 } 51 ltsh->ypels.push_back(pel); 52 } 53 54 return true; 55 } 56 57 bool ots_ltsh_should_serialise(OpenTypeFile *file) { 58 if (!file->glyf) return false; // this table is not for CFF fonts. 59 return file->ltsh != NULL; 60 } 61 62 bool ots_ltsh_serialise(OTSStream *out, OpenTypeFile *file) { 63 const OpenTypeLTSH *ltsh = file->ltsh; 64 65 if (!out->WriteU16(ltsh->version) || 66 !out->WriteU16(ltsh->ypels.size())) { 67 return OTS_FAILURE(); 68 } 69 for (unsigned i = 0; i < ltsh->ypels.size(); ++i) { 70 if (!out->Write(&(ltsh->ypels[i]), 1)) { 71 return OTS_FAILURE(); 72 } 73 } 74 75 return true; 76 } 77 78 void ots_ltsh_free(OpenTypeFile *file) { 79 delete file->ltsh; 80 } 81 82 } // namespace ots 83
