1 /*
2 ****************************************************************************** *
3 *
4 * Copyright (C) 1999-2003, International Business Machines
5 * Corporation and others. All Rights Reserved.
6 *
7 ****************************************************************************** *
8 * file name: cmaps.cpp
9 *
10 * created on: ??/??/2001
11 * created by: Eric R. Mader
12 */
13
14 #include "layout/LETypes.h"
15 #include "layout/LESwaps.h"
16
17 #include "sfnt.h"
18 #include "cmaps.h"
19
20 #define SWAPU16(code) ((LEUnicode16) SWAPW(code))
21 #define SWAPU32(code) ((LEUnicode32) SWAPL(code))
22
23 //
24 // Finds the high bit by binary searching
25 // through the bits in value.
26 //
highBit(le_uint32 value)27 le_uint8 highBit(le_uint32 value)
28 {
29 le_uint8 bit = 0;
30
31 if (value >= 1 << 16) {
32 value >>= 16;
33 bit += 16;
34 }
35
36 if (value >= 1 << 8) {
37 value >>= 8;
38 bit += 8;
39 }
40
41 if (value >= 1 << 4) {
42 value >>= 4;
43 bit += 4;
44 }
45
46 if (value >= 1 << 2) {
47 value >>= 2;
48 bit += 2;
49 }
50
51 if (value >= 1 << 1) {
52 value >>= 1;
53 bit += 1;
54 }
55
56 return bit;
57 }
58
createUnicodeMapper(const CMAPTable * cmap)59 CMAPMapper *CMAPMapper::createUnicodeMapper(const CMAPTable *cmap)
60 {
61 le_uint16 i;
62 le_uint16 nSubtables = SWAPW(cmap->numberSubtables);
63 const CMAPEncodingSubtable *subtable = NULL;
64 le_uint32 offset1 = 0, offset10 = 0;
65
66 for (i = 0; i < nSubtables; i += 1) {
67 const CMAPEncodingSubtableHeader *esh = &cmap->encodingSubtableHeaders[i];
68
69 if (SWAPW(esh->platformID) == 3) {
70 switch (SWAPW(esh->platformSpecificID)) {
71 case 1:
72 offset1 = SWAPL(esh->encodingOffset);
73 break;
74
75 case 10:
76 offset10 = SWAPL(esh->encodingOffset);
77 break;
78 }
79 }
80 }
81
82
83 if (offset10 != 0)
84 {
85 subtable = (const CMAPEncodingSubtable *) ((const char *) cmap + offset10);
86 } else if (offset1 != 0) {
87 subtable = (const CMAPEncodingSubtable *) ((const char *) cmap + offset1);
88 } else {
89 return NULL;
90 }
91
92 switch (SWAPW(subtable->format)) {
93 case 4:
94 return new CMAPFormat4Mapper(cmap, (const CMAPFormat4Encoding *) subtable);
95
96 case 12:
97 {
98 const CMAPFormat12Encoding *encoding = (const CMAPFormat12Encoding *) subtable;
99
100 return new CMAPGroupMapper(cmap, encoding->groups, SWAPL(encoding->nGroups));
101 }
102
103 default:
104 break;
105 }
106
107 return NULL;
108 }
109
CMAPFormat4Mapper(const CMAPTable * cmap,const CMAPFormat4Encoding * header)110 CMAPFormat4Mapper::CMAPFormat4Mapper(const CMAPTable *cmap, const CMAPFormat4Encoding *header)
111 : CMAPMapper(cmap)
112 {
113 le_uint16 segCount = SWAPW(header->segCountX2) / 2;
114
115 fEntrySelector = SWAPW(header->entrySelector);
116 fRangeShift = SWAPW(header->rangeShift) / 2;
117 fEndCodes = &header->endCodes[0];
118 fStartCodes = &header->endCodes[segCount + 1]; // + 1 for reservedPad...
119 fIdDelta = &fStartCodes[segCount];
120 fIdRangeOffset = &fIdDelta[segCount];
121 }
122
unicodeToGlyph(LEUnicode32 unicode32) const123 LEGlyphID CMAPFormat4Mapper::unicodeToGlyph(LEUnicode32 unicode32) const
124 {
125 if (unicode32 >= 0x10000) {
126 return 0;
127 }
128
129 LEUnicode16 unicode = (LEUnicode16) unicode32;
130 le_uint16 index = 0;
131 le_uint16 probe = 1 << fEntrySelector;
132 TTGlyphID result = 0;
133
134 if (SWAPU16(fStartCodes[fRangeShift]) <= unicode) {
135 index = fRangeShift;
136 }
137
138 while (probe > (1 << 0)) {
139 probe >>= 1;
140
141 if (SWAPU16(fStartCodes[index + probe]) <= unicode) {
142 index += probe;
143 }
144 }
145
146 if (unicode >= SWAPU16(fStartCodes[index]) && unicode <= SWAPU16(fEndCodes[index])) {
147 if (fIdRangeOffset[index] == 0) {
148 result = (TTGlyphID) unicode;
149 } else {
150 le_uint16 offset = unicode - SWAPU16(fStartCodes[index]);
151 le_uint16 rangeOffset = SWAPW(fIdRangeOffset[index]);
152 le_uint16 *glyphIndexTable = (le_uint16 *) ((char *) &fIdRangeOffset[index] + rangeOffset);
153
154 result = SWAPW(glyphIndexTable[offset]);
155 }
156
157 result += SWAPW(fIdDelta[index]);
158 } else {
159 result = 0;
160 }
161
162 return LE_SET_GLYPH(0, result);
163 }
164
~CMAPFormat4Mapper()165 CMAPFormat4Mapper::~CMAPFormat4Mapper()
166 {
167 // parent destructor does it all
168 }
169
CMAPGroupMapper(const CMAPTable * cmap,const CMAPGroup * groups,le_uint32 nGroups)170 CMAPGroupMapper::CMAPGroupMapper(const CMAPTable *cmap, const CMAPGroup *groups, le_uint32 nGroups)
171 : CMAPMapper(cmap), fGroups(groups)
172 {
173 le_uint8 bit = highBit(nGroups);
174 fPower = 1 << bit;
175 fRangeOffset = nGroups - fPower;
176 }
177
unicodeToGlyph(LEUnicode32 unicode32) const178 LEGlyphID CMAPGroupMapper::unicodeToGlyph(LEUnicode32 unicode32) const
179 {
180 le_int32 probe = fPower;
181 le_int32 range = 0;
182
183 if (SWAPU32(fGroups[fRangeOffset].startCharCode) <= unicode32) {
184 range = fRangeOffset;
185 }
186
187 while (probe > (1 << 0)) {
188 probe >>= 1;
189
190 if (SWAPU32(fGroups[range + probe].startCharCode) <= unicode32) {
191 range += probe;
192 }
193 }
194
195 if (SWAPU32(fGroups[range].startCharCode) <= unicode32 && SWAPU32(fGroups[range].endCharCode) >= unicode32) {
196 return (LEGlyphID) (SWAPU32(fGroups[range].startGlyphCode) + unicode32 - SWAPU32(fGroups[range].startCharCode));
197 }
198
199 return 0;
200 }
201
~CMAPGroupMapper()202 CMAPGroupMapper::~CMAPGroupMapper()
203 {
204 // parent destructor does it all
205 }
206
207