gfx/ots/src/gasp.cc@6474c204b198 (annotated)
gfx/ots/src/gasp.cc
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | // Copyright (c) 2009 The Chromium Authors. All rights reserved. |
| michael@0 | 2 | // Use of this source code is governed by a BSD-style license that can be |
| michael@0 | 3 | // found in the LICENSE file. |
| michael@0 | 4 | |
| michael@0 | 5 | #include "gasp.h" |
| michael@0 | 6 | |
| michael@0 | 7 | // gasp - Grid-fitting And Scan-conversion Procedure |
| michael@0 | 8 | // http://www.microsoft.com/typography/otspec/gasp.htm |
| michael@0 | 9 | |
| michael@0 | 10 | #define TABLE_NAME "gasp" |
| michael@0 | 11 | |
| michael@0 | 12 | #define DROP_THIS_TABLE \ |
| michael@0 | 13 | do { \ |
| michael@0 | 14 | delete file->gasp; \ |
| michael@0 | 15 | file->gasp = 0; \ |
| michael@0 | 16 | OTS_FAILURE_MSG("Table discarded"); \ |
| michael@0 | 17 | } while (0) |
| michael@0 | 18 | |
| michael@0 | 19 | namespace ots { |
| michael@0 | 20 | |
| michael@0 | 21 | bool ots_gasp_parse(OpenTypeFile *file, const uint8_t *data, size_t length) { |
| michael@0 | 22 | Buffer table(data, length); |
| michael@0 | 23 | |
| michael@0 | 24 | OpenTypeGASP *gasp = new OpenTypeGASP; |
| michael@0 | 25 | file->gasp = gasp; |
| michael@0 | 26 | |
| michael@0 | 27 | uint16_t num_ranges = 0; |
| michael@0 | 28 | if (!table.ReadU16(&gasp->version) || |
| michael@0 | 29 | !table.ReadU16(&num_ranges)) { |
| michael@0 | 30 | return OTS_FAILURE_MSG("Failed to read table header"); |
| michael@0 | 31 | } |
| michael@0 | 32 | |
| michael@0 | 33 | if (gasp->version > 1) { |
| michael@0 | 34 | // Lots of Linux fonts have bad version numbers... |
| michael@0 | 35 | OTS_WARNING("bad version: %u", gasp->version); |
| michael@0 | 36 | DROP_THIS_TABLE; |
| michael@0 | 37 | return true; |
| michael@0 | 38 | } |
| michael@0 | 39 | |
| michael@0 | 40 | if (num_ranges == 0) { |
| michael@0 | 41 | OTS_WARNING("num_ranges is zero"); |
| michael@0 | 42 | DROP_THIS_TABLE; |
| michael@0 | 43 | return true; |
| michael@0 | 44 | } |
| michael@0 | 45 | |
| michael@0 | 46 | gasp->gasp_ranges.reserve(num_ranges); |
| michael@0 | 47 | for (unsigned i = 0; i < num_ranges; ++i) { |
| michael@0 | 48 | uint16_t max_ppem = 0; |
| michael@0 | 49 | uint16_t behavior = 0; |
| michael@0 | 50 | if (!table.ReadU16(&max_ppem) || |
| michael@0 | 51 | !table.ReadU16(&behavior)) { |
| michael@0 | 52 | return OTS_FAILURE_MSG("Failed to read subrange %d", i); |
| michael@0 | 53 | } |
| michael@0 | 54 | if ((i > 0) && (gasp->gasp_ranges[i - 1].first >= max_ppem)) { |
| michael@0 | 55 | // The records in the gaspRange[] array must be sorted in order of |
| michael@0 | 56 | // increasing rangeMaxPPEM value. |
| michael@0 | 57 | OTS_WARNING("ranges are not sorted"); |
| michael@0 | 58 | DROP_THIS_TABLE; |
| michael@0 | 59 | return true; |
| michael@0 | 60 | } |
| michael@0 | 61 | if ((i == num_ranges - 1u) && // never underflow. |
| michael@0 | 62 | (max_ppem != 0xffffu)) { |
| michael@0 | 63 | OTS_WARNING("The last record should be 0xFFFF as a sentinel value " |
| michael@0 | 64 | "for rangeMaxPPEM"); |
| michael@0 | 65 | DROP_THIS_TABLE; |
| michael@0 | 66 | return true; |
| michael@0 | 67 | } |
| michael@0 | 68 | |
| michael@0 | 69 | if (behavior >> 8) { |
| michael@0 | 70 | OTS_WARNING("undefined bits are used: %x", behavior); |
| michael@0 | 71 | // mask undefined bits. |
| michael@0 | 72 | behavior &= 0x000fu; |
| michael@0 | 73 | } |
| michael@0 | 74 | |
| michael@0 | 75 | if (gasp->version == 0 && (behavior >> 2) != 0) { |
| michael@0 | 76 | OTS_WARNING("changed the version number to 1"); |
| michael@0 | 77 | gasp->version = 1; |
| michael@0 | 78 | } |
| michael@0 | 79 | |
| michael@0 | 80 | gasp->gasp_ranges.push_back(std::make_pair(max_ppem, behavior)); |
| michael@0 | 81 | } |
| michael@0 | 82 | |
| michael@0 | 83 | return true; |
| michael@0 | 84 | } |
| michael@0 | 85 | |
| michael@0 | 86 | bool ots_gasp_should_serialise(OpenTypeFile *file) { |
| michael@0 | 87 | return file->gasp != NULL; |
| michael@0 | 88 | } |
| michael@0 | 89 | |
| michael@0 | 90 | bool ots_gasp_serialise(OTSStream *out, OpenTypeFile *file) { |
| michael@0 | 91 | const OpenTypeGASP *gasp = file->gasp; |
| michael@0 | 92 | |
| michael@0 | 93 | if (!out->WriteU16(gasp->version) || |
| michael@0 | 94 | !out->WriteU16(gasp->gasp_ranges.size())) { |
| michael@0 | 95 | return OTS_FAILURE_MSG("failed to write gasp header"); |
| michael@0 | 96 | } |
| michael@0 | 97 | |
| michael@0 | 98 | for (unsigned i = 0; i < gasp->gasp_ranges.size(); ++i) { |
| michael@0 | 99 | if (!out->WriteU16(gasp->gasp_ranges[i].first) || |
| michael@0 | 100 | !out->WriteU16(gasp->gasp_ranges[i].second)) { |
| michael@0 | 101 | return OTS_FAILURE_MSG("Failed to write gasp subtable %d", i); |
| michael@0 | 102 | } |
| michael@0 | 103 | } |
| michael@0 | 104 | |
| michael@0 | 105 | return true; |
| michael@0 | 106 | } |
| michael@0 | 107 | |
| michael@0 | 108 | void ots_gasp_free(OpenTypeFile *file) { |
| michael@0 | 109 | delete file->gasp; |
| michael@0 | 110 | } |
| michael@0 | 111 | |
| michael@0 | 112 | } // namespace ots |
