1 /*
2 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
3 * (C) 1999 Antti Koivisto (koivisto@kde.org)
4 * (C) 2000 Dirk Mueller (mueller@kde.org)
5 * Copyright (C) 2003, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public License
18 * along with this library; see the file COPYING.LIB. If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
21 */
22
23 #include "config.h"
24 #include "ComplexTextController.h"
25
26 #if USE(ATSUI)
27
28 #include "Font.h"
29 #include "ShapeArabic.h"
30 #include "TextRun.h"
31 #include <wtf/unicode/CharacterNames.h>
32
33 #ifdef __LP64__
34 // ATSUTextInserted() is SPI in 64-bit.
35 extern "C" {
36 OSStatus ATSUTextInserted(ATSUTextLayout iTextLayout, UniCharArrayOffset iInsertionLocation, UniCharCount iInsertionLength);
37 }
38 #endif
39
40 using namespace WTF::Unicode;
41
42 namespace WebCore {
43
overrideLayoutOperation(ATSULayoutOperationSelector,ATSULineRef atsuLineRef,URefCon refCon,void *,ATSULayoutOperationCallbackStatus * callbackStatus)44 OSStatus ComplexTextController::ComplexTextRun::overrideLayoutOperation(ATSULayoutOperationSelector, ATSULineRef atsuLineRef, URefCon refCon, void*, ATSULayoutOperationCallbackStatus* callbackStatus)
45 {
46 ComplexTextRun* complexTextRun = reinterpret_cast<ComplexTextRun*>(refCon);
47 OSStatus status;
48 ItemCount count;
49 ATSLayoutRecord* layoutRecords;
50
51 status = ATSUDirectGetLayoutDataArrayPtrFromLineRef(atsuLineRef, kATSUDirectDataLayoutRecordATSLayoutRecordCurrent, true, reinterpret_cast<void**>(&layoutRecords), &count);
52 if (status != noErr) {
53 *callbackStatus = kATSULayoutOperationCallbackStatusContinue;
54 return status;
55 }
56
57 count--;
58 ItemCount j = 0;
59 CFIndex indexOffset = 0;
60
61 if (complexTextRun->m_directionalOverride) {
62 j++;
63 count -= 2;
64 indexOffset = -1;
65 }
66
67 complexTextRun->m_glyphCount = count;
68 complexTextRun->m_glyphsVector.reserveCapacity(count);
69 complexTextRun->m_advancesVector.reserveCapacity(count);
70 complexTextRun->m_atsuiIndices.reserveCapacity(count);
71
72 bool atBeginning = true;
73 CGFloat lastX = 0;
74
75 for (ItemCount i = 0; i < count; ++i, ++j) {
76 if (layoutRecords[j].glyphID == kATSDeletedGlyphcode) {
77 complexTextRun->m_glyphCount--;
78 continue;
79 }
80 complexTextRun->m_glyphsVector.uncheckedAppend(layoutRecords[j].glyphID);
81 complexTextRun->m_atsuiIndices.uncheckedAppend(layoutRecords[j].originalOffset / 2 + indexOffset);
82 CGFloat x = FixedToFloat(layoutRecords[j].realPos);
83 if (!atBeginning)
84 complexTextRun->m_advancesVector.uncheckedAppend(CGSizeMake(x - lastX, 0));
85 lastX = x;
86 atBeginning = false;
87 }
88
89 complexTextRun->m_advancesVector.uncheckedAppend(CGSizeMake(FixedToFloat(layoutRecords[j].realPos) - lastX, 0));
90
91 complexTextRun->m_glyphs = complexTextRun->m_glyphsVector.data();
92 complexTextRun->m_advances = complexTextRun->m_advancesVector.data();
93
94 status = ATSUDirectReleaseLayoutDataArrayPtr(atsuLineRef, kATSUDirectDataLayoutRecordATSLayoutRecordCurrent, reinterpret_cast<void**>(&layoutRecords));
95 *callbackStatus = kATSULayoutOperationCallbackStatusContinue;
96 return noErr;
97 }
98
isArabicLamWithAlefLigature(UChar c)99 static inline bool isArabicLamWithAlefLigature(UChar c)
100 {
101 return c >= 0xfef5 && c <= 0xfefc;
102 }
103
shapeArabic(const UChar * source,UChar * dest,unsigned totalLength)104 static void shapeArabic(const UChar* source, UChar* dest, unsigned totalLength)
105 {
106 unsigned shapingStart = 0;
107 while (shapingStart < totalLength) {
108 unsigned shapingEnd;
109 // We do not want to pass a Lam with Alef ligature followed by a space to the shaper,
110 // since we want to be able to identify this sequence as the result of shaping a Lam
111 // followed by an Alef and padding with a space.
112 bool foundLigatureSpace = false;
113 for (shapingEnd = shapingStart; !foundLigatureSpace && shapingEnd < totalLength - 1; ++shapingEnd)
114 foundLigatureSpace = isArabicLamWithAlefLigature(source[shapingEnd]) && source[shapingEnd + 1] == ' ';
115 shapingEnd++;
116
117 UErrorCode shapingError = U_ZERO_ERROR;
118 unsigned charsWritten = shapeArabic(source + shapingStart, shapingEnd - shapingStart, dest + shapingStart, shapingEnd - shapingStart, U_SHAPE_LETTERS_SHAPE | U_SHAPE_LENGTH_FIXED_SPACES_NEAR, &shapingError);
119
120 if (U_SUCCESS(shapingError) && charsWritten == shapingEnd - shapingStart) {
121 for (unsigned j = shapingStart; j < shapingEnd - 1; ++j) {
122 if (isArabicLamWithAlefLigature(dest[j]) && dest[j + 1] == ' ')
123 dest[++j] = zeroWidthSpace;
124 }
125 if (foundLigatureSpace) {
126 dest[shapingEnd] = ' ';
127 shapingEnd++;
128 } else if (isArabicLamWithAlefLigature(dest[shapingEnd - 1])) {
129 // u_shapeArabic quirk: if the last two characters in the source string are a Lam and an Alef,
130 // the space is put at the beginning of the string, despite U_SHAPE_LENGTH_FIXED_SPACES_NEAR.
131 ASSERT(dest[shapingStart] == ' ');
132 dest[shapingStart] = zeroWidthSpace;
133 }
134 } else {
135 // Something went wrong. Abandon shaping and just copy the rest of the buffer.
136 LOG_ERROR("u_shapeArabic failed(%d)", shapingError);
137 shapingEnd = totalLength;
138 memcpy(dest + shapingStart, source + shapingStart, (shapingEnd - shapingStart) * sizeof(UChar));
139 }
140 shapingStart = shapingEnd;
141 }
142 }
143
ComplexTextRun(ATSUTextLayout atsuTextLayout,const SimpleFontData * fontData,const UChar * characters,unsigned stringLocation,size_t stringLength,bool ltr,bool directionalOverride)144 ComplexTextController::ComplexTextRun::ComplexTextRun(ATSUTextLayout atsuTextLayout, const SimpleFontData* fontData, const UChar* characters, unsigned stringLocation, size_t stringLength, bool ltr, bool directionalOverride)
145 : m_fontData(fontData)
146 , m_characters(characters)
147 , m_stringLocation(stringLocation)
148 , m_stringLength(stringLength)
149 , m_indexEnd(stringLength)
150 , m_directionalOverride(directionalOverride)
151 , m_isMonotonic(true)
152 {
153 OSStatus status;
154
155 status = ATSUSetTextLayoutRefCon(atsuTextLayout, reinterpret_cast<URefCon>(this));
156
157 ATSLineLayoutOptions lineLayoutOptions = kATSLineKeepSpacesOutOfMargin | kATSLineHasNoHangers;
158
159 Boolean rtl = !ltr;
160
161 Vector<UChar, 256> substituteCharacters;
162 bool shouldCheckForMirroring = !ltr && !fontData->m_ATSUMirrors;
163 bool shouldCheckForArabic = !fontData->shapesArabic();
164 bool shouldShapeArabic = false;
165
166 bool mirrored = false;
167 for (size_t i = 0; i < stringLength; ++i) {
168 if (shouldCheckForMirroring) {
169 UChar mirroredChar = u_charMirror(characters[i]);
170 if (mirroredChar != characters[i]) {
171 if (!mirrored) {
172 mirrored = true;
173 substituteCharacters.grow(stringLength);
174 memcpy(substituteCharacters.data(), characters, stringLength * sizeof(UChar));
175 ATSUTextMoved(atsuTextLayout, substituteCharacters.data());
176 }
177 substituteCharacters[i] = mirroredChar;
178 }
179 }
180 if (shouldCheckForArabic && isArabicChar(characters[i])) {
181 shouldCheckForArabic = false;
182 shouldShapeArabic = true;
183 }
184 }
185
186 if (shouldShapeArabic) {
187 Vector<UChar, 256> shapedArabic(stringLength);
188 shapeArabic(substituteCharacters.isEmpty() ? characters : substituteCharacters.data(), shapedArabic.data(), stringLength);
189 substituteCharacters.swap(shapedArabic);
190 ATSUTextMoved(atsuTextLayout, substituteCharacters.data());
191 }
192
193 if (directionalOverride) {
194 UChar override = ltr ? leftToRightOverride : rightToLeftOverride;
195 if (substituteCharacters.isEmpty()) {
196 substituteCharacters.grow(stringLength + 2);
197 substituteCharacters[0] = override;
198 memcpy(substituteCharacters.data() + 1, characters, stringLength * sizeof(UChar));
199 substituteCharacters[stringLength + 1] = popDirectionalFormatting;
200 ATSUTextMoved(atsuTextLayout, substituteCharacters.data());
201 } else {
202 substituteCharacters.prepend(override);
203 substituteCharacters.append(popDirectionalFormatting);
204 }
205 ATSUTextInserted(atsuTextLayout, 0, 2);
206 }
207
208 ATSULayoutOperationOverrideSpecifier overrideSpecifier;
209 overrideSpecifier.operationSelector = kATSULayoutOperationPostLayoutAdjustment;
210 overrideSpecifier.overrideUPP = overrideLayoutOperation;
211
212 ATSUAttributeTag tags[] = { kATSULineLayoutOptionsTag, kATSULineDirectionTag, kATSULayoutOperationOverrideTag };
213 ByteCount sizes[] = { sizeof(ATSLineLayoutOptions), sizeof(Boolean), sizeof(ATSULayoutOperationOverrideSpecifier) };
214 ATSUAttributeValuePtr values[] = { &lineLayoutOptions, &rtl, &overrideSpecifier };
215
216 status = ATSUSetLayoutControls(atsuTextLayout, 3, tags, sizes, values);
217
218 ItemCount boundsCount;
219 status = ATSUGetGlyphBounds(atsuTextLayout, 0, 0, 0, m_stringLength, kATSUseFractionalOrigins, 0, 0, &boundsCount);
220
221 status = ATSUDisposeTextLayout(atsuTextLayout);
222 }
223
createTextRunFromFontDataATSUI(bool ltr)224 void ComplexTextController::ComplexTextRun::createTextRunFromFontDataATSUI(bool ltr)
225 {
226 m_atsuiIndices.reserveCapacity(m_stringLength);
227 unsigned r = 0;
228 while (r < m_stringLength) {
229 m_atsuiIndices.uncheckedAppend(r);
230 if (U_IS_SURROGATE(m_characters[r])) {
231 ASSERT(r + 1 < m_stringLength);
232 ASSERT(U_IS_SURROGATE_LEAD(m_characters[r]));
233 ASSERT(U_IS_TRAIL(m_characters[r + 1]));
234 r += 2;
235 } else
236 r++;
237 }
238 m_glyphCount = m_atsuiIndices.size();
239 if (!ltr) {
240 for (unsigned r = 0, end = m_glyphCount - 1; r < m_glyphCount / 2; ++r, --end)
241 std::swap(m_atsuiIndices[r], m_atsuiIndices[end]);
242 }
243
244 m_glyphsVector.fill(0, m_glyphCount);
245 m_glyphs = m_glyphsVector.data();
246 m_advancesVector.fill(CGSizeMake(m_fontData->widthForGlyph(0), 0), m_glyphCount);
247 m_advances = m_advancesVector.data();
248 }
249
fontHasMirroringInfo(ATSUFontID fontID)250 static bool fontHasMirroringInfo(ATSUFontID fontID)
251 {
252 ByteCount propTableSize;
253 OSStatus status = ATSFontGetTable(fontID, 'prop', 0, 0, 0, &propTableSize);
254 if (status == noErr) // naively assume that if a 'prop' table exists then it contains mirroring info
255 return true;
256 else if (status != kATSInvalidFontTableAccess) // anything other than a missing table is logged as an error
257 LOG_ERROR("ATSFontGetTable failed (%d)", static_cast<int>(status));
258
259 return false;
260 }
261
disableLigatures(const SimpleFontData * fontData,ATSUStyle atsuStyle,TypesettingFeatures typesettingFeatures)262 static void disableLigatures(const SimpleFontData* fontData, ATSUStyle atsuStyle, TypesettingFeatures typesettingFeatures)
263 {
264 // Don't be too aggressive: if the font doesn't contain 'a', then assume that any ligatures it contains are
265 // in characters that always go through ATSUI, and therefore allow them. Geeza Pro is an example.
266 // See bugzilla 5166.
267 if ((typesettingFeatures & Ligatures) || (fontData->platformData().orientation() == Horizontal && fontData->platformData().allowsLigatures()))
268 return;
269
270 ATSUFontFeatureType featureTypes[] = { kLigaturesType };
271 ATSUFontFeatureSelector featureSelectors[] = { kCommonLigaturesOffSelector };
272 OSStatus status = ATSUSetFontFeatures(atsuStyle, 1, featureTypes, featureSelectors);
273 if (status != noErr)
274 LOG_ERROR("ATSUSetFontFeatures failed (%d) -- ligatures remain enabled", static_cast<int>(status));
275 }
276
initializeATSUStyle(const SimpleFontData * fontData,TypesettingFeatures typesettingFeatures)277 static ATSUStyle initializeATSUStyle(const SimpleFontData* fontData, TypesettingFeatures typesettingFeatures)
278 {
279 unsigned key = typesettingFeatures + 1;
280 pair<HashMap<unsigned, ATSUStyle>::iterator, bool> addResult = fontData->m_ATSUStyleMap.add(key, 0);
281 ATSUStyle& atsuStyle = addResult.first->second;
282 if (!addResult.second)
283 return atsuStyle;
284
285 ATSUFontID fontID = fontData->platformData().ctFont() ? CTFontGetPlatformFont(fontData->platformData().ctFont(), 0) : 0;
286 if (!fontID) {
287 LOG_ERROR("unable to get ATSUFontID for %p", fontData->platformData().font());
288 fontData->m_ATSUStyleMap.remove(addResult.first);
289 return 0;
290 }
291
292 OSStatus status = ATSUCreateStyle(&atsuStyle);
293 if (status != noErr)
294 LOG_ERROR("ATSUCreateStyle failed (%d)", static_cast<int>(status));
295
296 Fixed fontSize = FloatToFixed(fontData->platformData().m_size);
297 Fract kerningInhibitFactor = FloatToFract(1);
298 static CGAffineTransform verticalFlip = CGAffineTransformMakeScale(1, -1);
299
300 ByteCount styleSizes[4] = { sizeof(fontSize), sizeof(fontID), sizeof(verticalFlip), sizeof(kerningInhibitFactor) };
301 ATSUAttributeTag styleTags[4] = { kATSUSizeTag, kATSUFontTag, kATSUFontMatrixTag, kATSUKerningInhibitFactorTag };
302 ATSUAttributeValuePtr styleValues[4] = { &fontSize, &fontID, &verticalFlip, &kerningInhibitFactor };
303
304 bool allowKerning = typesettingFeatures & Kerning;
305 status = ATSUSetAttributes(atsuStyle, allowKerning ? 3 : 4, styleTags, styleSizes, styleValues);
306 if (status != noErr)
307 LOG_ERROR("ATSUSetAttributes failed (%d)", static_cast<int>(status));
308
309 fontData->m_ATSUMirrors = fontHasMirroringInfo(fontID);
310
311 disableLigatures(fontData, atsuStyle, typesettingFeatures);
312 return atsuStyle;
313 }
314
collectComplexTextRunsForCharactersATSUI(const UChar * cp,unsigned length,unsigned stringLocation,const SimpleFontData * fontData)315 void ComplexTextController::collectComplexTextRunsForCharactersATSUI(const UChar* cp, unsigned length, unsigned stringLocation, const SimpleFontData* fontData)
316 {
317 if (!fontData) {
318 // Create a run of missing glyphs from the primary font.
319 m_complexTextRuns.append(ComplexTextRun::create(m_font.primaryFont(), cp, stringLocation, length, m_run.ltr()));
320 return;
321 }
322
323 if (m_fallbackFonts && fontData != m_font.primaryFont())
324 m_fallbackFonts->add(fontData);
325
326 ATSUStyle atsuStyle = initializeATSUStyle(fontData, m_font.typesettingFeatures());
327
328 OSStatus status;
329 ATSUTextLayout atsuTextLayout;
330 UniCharCount runLength = length;
331
332 status = ATSUCreateTextLayoutWithTextPtr(cp, 0, length, length, 1, &runLength, &atsuStyle, &atsuTextLayout);
333 if (status != noErr) {
334 LOG_ERROR("ATSUCreateTextLayoutWithTextPtr failed with error %d", static_cast<int>(status));
335 return;
336 }
337 m_complexTextRuns.append(ComplexTextRun::create(atsuTextLayout, fontData, cp, stringLocation, length, m_run.ltr(), m_run.directionalOverride()));
338 }
339
340 } // namespace WebCore
341
342 #endif // USE(ATSUI)
343