Commit | Line | Data |
---|---|---|
b75a7d8f A |
1 | /*************************************************************************** |
2 | * | |
3 | * Copyright (C) 1998-2002, International Business Machines | |
4 | * Corporation and others. All Rights Reserved. | |
5 | * | |
6 | ************************************************************************/ | |
7 | ||
8 | #include <stdio.h> | |
9 | ||
10 | #include "LETypes.h" | |
11 | #include "FontObject.h" | |
12 | #include "LESwaps.h" | |
13 | ||
14 | FontObject::FontObject(char *fileName) | |
15 | : directory(NULL), numTables(0), searchRange(0),entrySelector(0), | |
16 | cmapTable(NULL), cmSegCount(0), cmSearchRange(0), cmEntrySelector(0), | |
17 | cmEndCodes(NULL), cmStartCodes(NULL), cmIdDelta(0), cmIdRangeOffset(0), | |
18 | headTable(NULL), hmtxTable(NULL), numGlyphs(0), numOfLongHorMetrics(0), file(NULL) | |
19 | { | |
20 | file = fopen(fileName, "rb"); | |
21 | ||
22 | if (file == NULL) { | |
23 | printf("?? Couldn't open %s", fileName); | |
24 | return; | |
25 | } | |
26 | ||
27 | SFNTDirectory tempDir; | |
28 | ||
29 | fread(&tempDir, sizeof tempDir, 1, file); | |
30 | ||
31 | numTables = SWAPW(tempDir.numTables); | |
32 | searchRange = SWAPW(tempDir.searchRange) >> 4; | |
33 | entrySelector = SWAPW(tempDir.entrySelector); | |
34 | rangeShift = SWAPW(tempDir.rangeShift) >> 4; | |
35 | ||
36 | int dirSize = sizeof tempDir + ((numTables - ANY_NUMBER) * sizeof(DirectoryEntry)); | |
37 | ||
38 | directory = (SFNTDirectory *) new char[dirSize]; | |
39 | ||
40 | fseek(file, 0L, SEEK_SET); | |
41 | fread(directory, sizeof(char), dirSize, file); | |
42 | ||
43 | initUnicodeCMAP(); | |
44 | } | |
45 | ||
46 | FontObject::~FontObject() | |
47 | { | |
48 | fclose(file); | |
49 | delete[] directory; | |
50 | delete[] cmapTable; | |
51 | delete[] headTable; | |
52 | delete[] hmtxTable; | |
53 | } | |
54 | ||
55 | void FontObject::deleteTable(void *table) | |
56 | { | |
57 | delete[] (char *) table; | |
58 | } | |
59 | ||
60 | DirectoryEntry *FontObject::findTable(LETag tag) | |
61 | { | |
62 | le_uint16 table = 0; | |
63 | le_uint16 probe = 1 << entrySelector; | |
64 | ||
65 | if (SWAPL(directory->tableDirectory[rangeShift].tag) <= tag) { | |
66 | table = rangeShift; | |
67 | } | |
68 | ||
69 | while (probe > (1 << 0)) { | |
70 | probe >>= 1; | |
71 | ||
72 | if (SWAPL(directory->tableDirectory[table + probe].tag) <= tag) { | |
73 | table += probe; | |
74 | } | |
75 | } | |
76 | ||
77 | if (SWAPL(directory->tableDirectory[table].tag) == tag) { | |
78 | return &directory->tableDirectory[table]; | |
79 | } | |
80 | ||
81 | return NULL; | |
82 | } | |
83 | ||
84 | void *FontObject::readTable(LETag tag, le_uint32 *length) | |
85 | { | |
86 | DirectoryEntry *entry = findTable(tag); | |
87 | ||
88 | if (entry == NULL) { | |
89 | *length = 0; | |
90 | return NULL; | |
91 | } | |
92 | ||
93 | *length = SWAPL(entry->length); | |
94 | ||
95 | void *table = new char[*length]; | |
96 | ||
97 | fseek(file, SWAPL(entry->offset), SEEK_SET); | |
98 | fread(table, sizeof(char), *length, file); | |
99 | ||
100 | return table; | |
101 | } | |
102 | ||
103 | CMAPEncodingSubtable *FontObject::findCMAP(le_uint16 platformID, le_uint16 platformSpecificID) | |
104 | { | |
105 | LETag cmapTag = 0x636D6170; // 'cmap' | |
106 | ||
107 | if (cmapTable == NULL) { | |
108 | le_uint32 length; | |
109 | ||
110 | cmapTable = (CMAPTable *) readTable(cmapTag, &length); | |
111 | } | |
112 | ||
113 | if (cmapTable != NULL) { | |
114 | le_uint16 i; | |
115 | le_uint16 nSubtables = SWAPW(cmapTable->numberSubtables); | |
116 | ||
117 | ||
118 | for (i = 0; i < nSubtables; i += 1) { | |
119 | CMAPEncodingSubtableHeader *esh = &cmapTable->encodingSubtableHeaders[i]; | |
120 | ||
121 | if (SWAPW(esh->platformID) == platformID && | |
122 | SWAPW(esh->platformSpecificID) == platformSpecificID) { | |
123 | return (CMAPEncodingSubtable *) ((char *) cmapTable + SWAPL(esh->encodingOffset)); | |
124 | } | |
125 | } | |
126 | } | |
127 | ||
128 | return NULL; | |
129 | } | |
130 | ||
131 | void FontObject::initUnicodeCMAP() | |
132 | { | |
133 | CMAPEncodingSubtable *encodingSubtable = findCMAP(3, 1); | |
134 | ||
135 | if (encodingSubtable == 0 || | |
136 | SWAPW(encodingSubtable->format) != 4) { | |
137 | printf("Can't find unicode 'cmap'"); | |
138 | return; | |
139 | } | |
140 | ||
141 | CMAPFormat4Encoding *header = (CMAPFormat4Encoding *) encodingSubtable; | |
142 | ||
143 | cmSegCount = SWAPW(header->segCountX2) / 2; | |
144 | cmSearchRange = SWAPW(header->searchRange); | |
145 | cmEntrySelector = SWAPW(header->entrySelector); | |
146 | cmRangeShift = SWAPW(header->rangeShift) / 2; | |
147 | cmEndCodes = &header->endCodes[0]; | |
148 | cmStartCodes = &header->endCodes[cmSegCount + 1]; // + 1 for reservedPad... | |
149 | cmIdDelta = &cmStartCodes[cmSegCount]; | |
150 | cmIdRangeOffset = &cmIdDelta[cmSegCount]; | |
151 | } | |
152 | ||
153 | LEGlyphID FontObject::unicodeToGlyph(LEUnicode32 unicode32) | |
154 | { | |
155 | if (unicode32 >= 0x10000) { | |
156 | return 0; | |
157 | } | |
158 | ||
159 | LEUnicode16 unicode = (LEUnicode16) unicode32; | |
160 | le_uint16 index = 0; | |
161 | le_uint16 probe = 1 << cmEntrySelector; | |
162 | LEGlyphID result = 0; | |
163 | ||
164 | if (SWAPW(cmStartCodes[cmRangeShift]) <= unicode) { | |
165 | index = cmRangeShift; | |
166 | } | |
167 | ||
168 | while (probe > (1 << 0)) { | |
169 | probe >>= 1; | |
170 | ||
171 | if (SWAPW(cmStartCodes[index + probe]) <= unicode) { | |
172 | index += probe; | |
173 | } | |
174 | } | |
175 | ||
176 | if (unicode >= SWAPW(cmStartCodes[index]) && unicode <= SWAPW(cmEndCodes[index])) { | |
177 | if (cmIdRangeOffset[index] == 0) { | |
178 | result = (LEGlyphID) unicode; | |
179 | } else { | |
180 | le_uint16 offset = unicode - SWAPW(cmStartCodes[index]); | |
181 | le_uint16 rangeOffset = SWAPW(cmIdRangeOffset[index]); | |
182 | le_uint16 *glyphIndexTable = (le_uint16 *) ((char *) &cmIdRangeOffset[index] + rangeOffset); | |
183 | ||
184 | result = SWAPW(glyphIndexTable[offset]); | |
185 | } | |
186 | ||
187 | result += SWAPW(cmIdDelta[index]); | |
188 | } else { | |
189 | result = 0; | |
190 | } | |
191 | ||
192 | return result; | |
193 | } | |
194 | ||
195 | le_uint16 FontObject::getUnitsPerEM() | |
196 | { | |
197 | if (headTable == NULL) { | |
198 | LETag headTag = 0x68656164; // 'head' | |
199 | le_uint32 length; | |
200 | ||
201 | headTable = (HEADTable *) readTable(headTag, &length); | |
202 | } | |
203 | ||
204 | return SWAPW(headTable->unitsPerEm); | |
205 | } | |
206 | ||
207 | le_uint16 FontObject::getGlyphAdvance(LEGlyphID glyph) | |
208 | { | |
209 | if (hmtxTable == NULL) { | |
210 | LETag maxpTag = 0x6D617870; // 'maxp' | |
211 | LETag hheaTag = 0x68686561; // 'hhea' | |
212 | LETag hmtxTag = 0x686D7478; // 'hmtx' | |
213 | le_uint32 length; | |
214 | HHEATable *hheaTable; | |
215 | MAXPTable *maxpTable = (MAXPTable *) readTable(maxpTag, &length); | |
216 | ||
217 | numGlyphs = SWAPW(maxpTable->numGlyphs); | |
218 | deleteTable(maxpTable); | |
219 | ||
220 | hheaTable = (HHEATable *) readTable(hheaTag, &length); | |
221 | numOfLongHorMetrics = SWAPW(hheaTable->numOfLongHorMetrics); | |
222 | deleteTable(hheaTable); | |
223 | ||
224 | hmtxTable = (HMTXTable *) readTable(hmtxTag, &length); | |
225 | } | |
226 | ||
227 | le_uint16 index = glyph; | |
228 | ||
229 | if (glyph >= numGlyphs) { | |
230 | return 0; | |
231 | } | |
232 | ||
233 | if (glyph >= numOfLongHorMetrics) { | |
234 | index = numOfLongHorMetrics - 1; | |
235 | } | |
236 | ||
237 | return SWAPW(hmtxTable->hMetrics[index].advanceWidth); | |
238 | } | |
239 | ||
240 |