1 /*
2 *
3 * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
4 *
5 */
6
7 #include "LETypes.h"
8 #include "LEGlyphFilter.h"
9 #include "OpenTypeTables.h"
10 #include "LEGlyphStorage.h"
11 #include "ThaiShaping.h"
12
13 U_NAMESPACE_BEGIN
14
15 enum {
16 CH_SPACE = 0x0020,
17 CH_YAMAKKAN = 0x0E4E,
18 CH_MAI_HANAKAT = 0x0E31,
19 CH_SARA_AA = 0x0E32,
20 CH_SARA_AM = 0x0E33,
21 CH_SARA_UEE = 0x0E37,
22 CH_MAITAIKHU = 0x0E47,
23 CH_NIKHAHIT = 0x0E4D,
24 CH_SARA_U = 0x0E38,
25 CH_PHINTHU = 0x0E3A,
26 CH_YO_YING = 0x0E0D,
27 CH_THO_THAN = 0x0E10,
28 CH_DOTTED_CIRCLE = 0x25CC
29 };
30
getCharClass(LEUnicode ch)31 le_uint8 ThaiShaping::getCharClass(LEUnicode ch)
32 {
33 le_uint8 charClass = NON;
34
35 if (ch >= 0x0E00 && ch <= 0x0E5B) {
36 charClass = classTable[ch - 0x0E00];
37 }
38
39 return charClass;
40 }
41
42
leftAboveVowel(LEUnicode vowel,le_uint8 glyphSet)43 LEUnicode ThaiShaping::leftAboveVowel(LEUnicode vowel, le_uint8 glyphSet)
44 {
45 static const LEUnicode leftAboveVowels[][7] = {
46 {0x0E61, 0x0E32, 0x0E33, 0x0E64, 0x0E65, 0x0E66, 0x0E67},
47 {0xF710, 0x0E32, 0x0E33, 0xF701, 0xF702, 0xF703, 0xF704},
48 {0xF884, 0x0E32, 0x0E33, 0xF885, 0xF886, 0xF887, 0xF788},
49 {0x0E31, 0x0E32, 0x0E33, 0x0E34, 0x0E35, 0x0E36, 0x0E37}
50 };
51
52 if (vowel >= CH_MAI_HANAKAT && vowel <= CH_SARA_UEE) {
53 return leftAboveVowels[glyphSet][vowel - CH_MAI_HANAKAT];
54 }
55
56 if (vowel == CH_YAMAKKAN && glyphSet == 0) {
57 return 0x0E7E;
58 }
59
60 return vowel;
61 }
62
lowerRightTone(LEUnicode tone,le_uint8 glyphSet)63 LEUnicode ThaiShaping::lowerRightTone(LEUnicode tone, le_uint8 glyphSet)
64 {
65 static const LEUnicode lowerRightTones[][7] = {
66 {0x0E68, 0x0E69, 0x0E6A, 0x0E6B, 0x0E6C, 0x0E6D, 0x0E6E},
67 {0x0E47, 0xF70A, 0xF70B, 0xF70C, 0xF70D, 0xF70E, 0x0E4D},
68 {0x0E47, 0xF88B, 0xF88E, 0xF891, 0xF894, 0xF897, 0x0E4D},
69 {0x0E47, 0x0E48, 0x0E49, 0x0E4A, 0x0E4B, 0x0E4C, 0x0E4D}
70 };
71
72 if (tone >= CH_MAITAIKHU && tone <= CH_NIKHAHIT) {
73 return lowerRightTones[glyphSet][tone - CH_MAITAIKHU];
74 }
75
76 return tone;
77 }
78
lowerLeftTone(LEUnicode tone,le_uint8 glyphSet)79 LEUnicode ThaiShaping::lowerLeftTone(LEUnicode tone, le_uint8 glyphSet)
80 {
81 static const LEUnicode lowerLeftTones[][7] = {
82 {0x0E76, 0x0E77, 0x0E78, 0x0E79, 0x0E7A, 0x0E7B, 0x0E7C},
83 {0xF712, 0xF705, 0xF706, 0xF707, 0xF708, 0xF709, 0xF711},
84 {0xF889, 0xF88C, 0xF88F, 0xF892, 0xF895, 0xF898, 0xF899},
85 {0x0E47, 0x0E48, 0x0E49, 0x0E4A, 0x0E4B, 0x0E4C, 0x0E4D}
86 };
87
88 if (tone >= CH_MAITAIKHU && tone <= CH_NIKHAHIT) {
89 return lowerLeftTones[glyphSet][tone - CH_MAITAIKHU];
90 }
91
92 return tone;
93 }
94
upperLeftTone(LEUnicode tone,le_uint8 glyphSet)95 LEUnicode ThaiShaping::upperLeftTone(LEUnicode tone, le_uint8 glyphSet)
96 {
97 static const LEUnicode upperLeftTones[][7] = {
98 {0x0E6F, 0x0E70, 0x0E71, 0x0E72, 0x0E73, 0x0E74, 0x0E75},
99 {0xF712, 0xF713, 0xF714, 0xF715, 0xF716, 0xF717, 0xF711},
100 {0xF889, 0xF88A, 0xF88D, 0xF890, 0xF893, 0xF896, 0xF899},
101 {0x0E47, 0x0E48, 0x0E49, 0x0E4A, 0x0E4B, 0x0E4C, 0x0E4D}
102 };
103
104 if (tone >= CH_MAITAIKHU && tone <= CH_NIKHAHIT) {
105 return upperLeftTones[glyphSet][tone - CH_MAITAIKHU];
106 }
107
108 return tone;
109 }
110
lowerBelowVowel(LEUnicode vowel,le_uint8 glyphSet)111 LEUnicode ThaiShaping::lowerBelowVowel(LEUnicode vowel, le_uint8 glyphSet)
112 {
113 static const LEUnicode lowerBelowVowels[][3] = {
114 {0x0E3C, 0x0E3D, 0x0E3E},
115 {0xF718, 0xF719, 0xF71A},
116 {0x0E38, 0x0E39, 0x0E3A},
117 {0x0E38, 0x0E39, 0x0E3A}
118
119 };
120
121 if (vowel >= CH_SARA_U && vowel <= CH_PHINTHU) {
122 return lowerBelowVowels[glyphSet][vowel - CH_SARA_U];
123 }
124
125 return vowel;
126 }
127
noDescenderCOD(LEUnicode cod,le_uint8 glyphSet)128 LEUnicode ThaiShaping::noDescenderCOD(LEUnicode cod, le_uint8 glyphSet)
129 {
130 static const LEUnicode noDescenderCODs[][4] = {
131 {0x0E60, 0x0E0E, 0x0E0F, 0x0E63},
132 {0xF70F, 0x0E0E, 0x0E0F, 0xF700},
133 {0x0E0D, 0x0E0E, 0x0E0F, 0x0E10},
134 {0x0E0D, 0x0E0E, 0x0E0F, 0x0E10}
135
136 };
137
138 if (cod >= CH_YO_YING && cod <= CH_THO_THAN) {
139 return noDescenderCODs[glyphSet][cod - CH_YO_YING];
140 }
141
142 return cod;
143 }
144
doTransition(StateTransition transition,LEUnicode currChar,le_int32 inputIndex,le_uint8 glyphSet,LEUnicode errorChar,LEUnicode * outputBuffer,LEGlyphStorage & glyphStorage,le_int32 & outputIndex)145 le_uint8 ThaiShaping::doTransition (StateTransition transition, LEUnicode currChar, le_int32 inputIndex, le_uint8 glyphSet,
146 LEUnicode errorChar, LEUnicode *outputBuffer, LEGlyphStorage &glyphStorage, le_int32 &outputIndex)
147 {
148 LEErrorCode success = LE_NO_ERROR;
149
150 switch (transition.action) {
151 case tA:
152 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
153 outputBuffer[outputIndex++] = currChar;
154 break;
155
156 case tC:
157 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
158 outputBuffer[outputIndex++] = currChar;
159 break;
160
161 case tD:
162 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
163 outputBuffer[outputIndex++] = leftAboveVowel(currChar, glyphSet);
164 break;
165
166 case tE:
167 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
168 outputBuffer[outputIndex++] = lowerRightTone(currChar, glyphSet);
169 break;
170
171 case tF:
172 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
173 outputBuffer[outputIndex++] = lowerLeftTone(currChar, glyphSet);
174 break;
175
176 case tG:
177 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
178 outputBuffer[outputIndex++] = upperLeftTone(currChar, glyphSet);
179 break;
180
181 case tH:
182 {
183 LEUnicode cod = outputBuffer[outputIndex - 1];
184 LEUnicode coa = noDescenderCOD(cod, glyphSet);
185
186 if (cod != coa) {
187 outputBuffer[outputIndex - 1] = coa;
188
189 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
190 outputBuffer[outputIndex++] = currChar;
191 break;
192 }
193
194 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
195 outputBuffer[outputIndex++] = lowerBelowVowel(currChar, glyphSet);
196 break;
197 }
198
199 case tR:
200 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
201 outputBuffer[outputIndex++] = errorChar;
202
203 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
204 outputBuffer[outputIndex++] = currChar;
205 break;
206
207 case tS:
208 if (currChar == CH_SARA_AM) {
209 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
210 outputBuffer[outputIndex++] = errorChar;
211 }
212
213 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
214 outputBuffer[outputIndex++] = currChar;
215 break;
216
217 default:
218 // FIXME: if we get here, there's an error
219 // in the state table!
220 glyphStorage.setCharIndex(outputIndex, inputIndex, success);
221 outputBuffer[outputIndex++] = currChar;
222 break;
223 }
224
225 return transition.nextState;
226 }
227
getNextState(LEUnicode ch,le_uint8 prevState,le_int32 inputIndex,le_uint8 glyphSet,LEUnicode errorChar,le_uint8 & charClass,LEUnicode * output,LEGlyphStorage & glyphStorage,le_int32 & outputIndex)228 le_uint8 ThaiShaping::getNextState(LEUnicode ch, le_uint8 prevState, le_int32 inputIndex, le_uint8 glyphSet, LEUnicode errorChar,
229 le_uint8 &charClass, LEUnicode *output, LEGlyphStorage &glyphStorage, le_int32 &outputIndex)
230 {
231 StateTransition transition;
232
233 charClass = getCharClass(ch);
234 transition = getTransition(prevState, charClass);
235
236 return doTransition(transition, ch, inputIndex, glyphSet, errorChar, output, glyphStorage, outputIndex);
237 }
238
isLegalHere(LEUnicode ch,le_uint8 prevState)239 le_bool ThaiShaping::isLegalHere(LEUnicode ch, le_uint8 prevState)
240 {
241 le_uint8 charClass = getCharClass(ch);
242 StateTransition transition = getTransition(prevState, charClass);
243
244 switch (transition.action) {
245 case tA:
246 case tC:
247 case tD:
248 case tE:
249 case tF:
250 case tG:
251 case tH:
252 return TRUE;
253
254 case tR:
255 case tS:
256 return FALSE;
257
258 default:
259 // FIXME: if we get here, there's an error
260 // in the state table!
261 return FALSE;
262 }
263 }
264
compose(const LEUnicode * input,le_int32 offset,le_int32 charCount,le_uint8 glyphSet,LEUnicode errorChar,LEUnicode * output,LEGlyphStorage & glyphStorage)265 le_int32 ThaiShaping::compose(const LEUnicode *input, le_int32 offset, le_int32 charCount, le_uint8 glyphSet,
266 LEUnicode errorChar, LEUnicode *output, LEGlyphStorage &glyphStorage)
267 {
268 le_uint8 state = 0;
269 le_int32 inputIndex;
270 le_int32 outputIndex = 0;
271 le_uint8 conState = 0xFF;
272 le_int32 conInput = -1;
273 le_int32 conOutput = -1;
274
275 for (inputIndex = 0; inputIndex < charCount; inputIndex += 1) {
276 LEUnicode ch = input[inputIndex + offset];
277 le_uint8 charClass;
278
279 // Decompose SARA AM into NIKHAHIT + SARA AA
280 if (ch == CH_SARA_AM && isLegalHere(ch, state)) {
281 outputIndex = conOutput;
282 state = getNextState(CH_NIKHAHIT, conState, inputIndex, glyphSet, errorChar, charClass,
283 output, glyphStorage, outputIndex);
284
285 for (int j = conInput + 1; j < inputIndex; j += 1) {
286 ch = input[j + offset];
287 state = getNextState(ch, state, j, glyphSet, errorChar, charClass,
288 output, glyphStorage, outputIndex);
289 }
290
291 ch = CH_SARA_AA;
292 }
293
294 state = getNextState(ch, state, inputIndex, glyphSet, errorChar, charClass,
295 output, glyphStorage, outputIndex);
296
297 if (charClass >= CON && charClass <= COD) {
298 conState = state;
299 conInput = inputIndex;
300 conOutput = outputIndex;
301 }
302 }
303
304 return outputIndex;
305 }
306
307 U_NAMESPACE_END
308