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diff --git a/dviware/dvisvgm/src/ttf/CmapTable.cpp b/dviware/dvisvgm/src/ttf/CmapTable.cpp
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+/*************************************************************************
+** CmapTable.cpp **
+** **
+** This file is part of dvisvgm -- a fast DVI to SVG converter **
+** Copyright (C) 2005-2023 Martin Gieseking <martin.gieseking@uos.de> **
+** **
+** This program is free software; you can redistribute it and/or **
+** modify it under the terms of the GNU General Public License as **
+** published by the Free Software Foundation; either version 3 of **
+** the License, or (at your option) any later version. **
+** **
+** This program is distributed in the hope that it will be useful, but **
+** WITHOUT ANY WARRANTY; without even the implied warranty of **
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the **
+** GNU General Public License for more details. **
+** **
+** You should have received a copy of the GNU General Public License **
+** along with this program; if not, see <http://www.gnu.org/licenses/>. **
+*************************************************************************/
+
+#include <algorithm>
+#include "CmapTable.hpp"
+#include "TTFWriter.hpp"
+#include "../Font.hpp"
+#include "../utility.hpp"
+
+using namespace std;
+using namespace ttf;
+
+void CmapTable::write (ostream &os) const {
+ writeUInt16(os, 0); // version
+ writeUInt16(os, 2); // number of encoding tables
+
+ const RangeMap &charmap = ttfWriter()->getUnicodeCharMap();
+ bool isUCS2 = (charmap.maxKey() <= 0xFFFF);
+ uint32_t offset = 4+2*8; // offset to subtable
+
+ writeUInt16(os, 0); // platform ID 0 = Unicode
+ writeUInt16(os, isUCS2 ? 3 : 4); // encoding ID (Unicode 2.0, UCS-2 or UCS-4)
+ writeUInt32(os, offset);
+
+ writeUInt16(os, 3); // platform ID 3 = Windows
+ writeUInt16(os, isUCS2 ? 1 : 10); // encoding ID (UCS-2 or UCS-4)
+ writeUInt32(os, offset); // platform ID 0 = Unicode
+
+ if (isUCS2)
+ writeSubTableFormat4(os, charmap);
+ else
+ writeSubTableFormat12(os, charmap);
+}
+
+
+/** Writes mapping data in subtable format 0 (byte encoding table). */
+void CmapTable::writeSubTableFormat0 (ostream &os, const RangeMap &charmap) const {
+ writeUInt16(os, 0); // subtable format
+ writeUInt16(os, 3*2+256); // table length
+ writeUInt16(os, 0); // language: none
+ vector<uint8_t> indexes(256, 0);
+ int count=1;
+ for (auto cppair : charmap) {
+ if (cppair.first > 255 || count > 255)
+ break;
+ indexes[cppair.first] = uint8_t(count++);
+ }
+ for (uint8_t c : indexes)
+ writeUInt8(os, c);
+}
+
+
+/** Writes mapping data in subtable format 4 (segment mapping to delta values, UCS-2). */
+void CmapTable::writeSubTableFormat4 (ostream &os, const RangeMap &charmap) const {
+ uint16_t numSegments = charmap.numRanges()+1;
+ uint16_t searchRange = 1 << (util::ilog2(numSegments)+1);
+ uint16_t entrySelector = util::ilog2(searchRange/2);
+ uint16_t rangeShift = 2*numSegments - searchRange;
+
+ writeUInt16(os, 4); // subtable format
+ writeUInt16(os, 8*2+4*2*numSegments); // table length
+ writeUInt16(os, 0); // language: none
+ writeUInt16(os, numSegments*2);
+ writeUInt16(os, searchRange);
+ writeUInt16(os, entrySelector);
+ writeUInt16(os, rangeShift);
+ for (size_t i=0; i < charmap.numRanges(); i++)
+ writeUInt16(os, charmap.getRange(i).max()); // end character code of current segment
+ writeUInt16(os, 0xFFFF); // final end character code
+ writeUInt16(os, 0); // reserved pad
+ for (size_t i=0; i < charmap.numRanges(); i++)
+ writeUInt16(os, charmap.getRange(i).min()); // start character code of current segment
+ writeUInt16(os, 0xFFFF); // final start character code
+ int count=1;
+ for (size_t i=0; i < charmap.numRanges(); i++) {
+ const auto &range = charmap.getRange(i);
+ int cstart = range.min();
+ writeInt16(os, count-cstart); // idDelta of current segment
+ count += range.numKeys();
+ }
+ writeUInt16(os, 1); // final idRange (maps 0xFFFF to 0)
+ for (uint16_t i=0; i < numSegments; i++)
+ writeUInt16(os, 0); // idRangeOffsets = 0 (no offsets into glyphIdArray required)
+}
+
+
+/** Writes mapping data in subtable format 6 (trimmed table mapping, UCS-2). */
+void CmapTable::writeSubTableFormat6 (ostream &os, const RangeMap &charmap) const {
+ writeUInt16(os, 6); // subtable format
+ writeUInt16(os, 5*2+2*charmap.numValues()); // table length
+ writeUInt16(os, 0); // language: none
+ writeUInt16(os, charmap.getRange(0).min()); // first character code
+ writeUInt16(os, charmap.getRange(0).numKeys());
+ for (size_t i=0; i < charmap.getRange(0).numKeys(); i++)
+ writeUInt16(os, i+1);
+}
+
+
+/** Writes mapping data in subtable format 12 (segmented coverage, UCS-4). */
+void CmapTable::writeSubTableFormat12 (ostream &os, const RangeMap &charmap) const {
+ writeUInt16(os, 12); // subtable format
+ writeUInt16(os, 0); // reserved
+ writeUInt32(os, 2*2+3*4+charmap.numRanges()*3*4); // table length
+ writeUInt32(os, 0); // language
+ writeUInt32(os, charmap.numRanges());
+ uint32_t startIndex=1;
+ for (size_t i=0; i < charmap.numRanges(); i++) {
+ const auto &range = charmap.getRange(i);
+ writeUInt32(os, range.min()); // startCharCode
+ writeUInt32(os, range.max()); // endCharCode
+ writeUInt32(os, startIndex); // startGlyphID
+ startIndex += range.numKeys();
+ }
+}