1 /* 2 * Copyright (c) 2006, 2007, 2008, 2009, 2012 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include "config.h" 32 #include "platform/fonts/win/UniscribeHelper.h" 33 34 #include "platform/fonts/Font.h" 35 #include "platform/fonts/skia/SkiaFontWin.h" 36 #include "platform/fonts/FontFallbackWin.h" 37 #include "platform/graphics/GraphicsContext.h" 38 #include "platform/win/HWndDC.h" 39 #include "third_party/skia/include/core/SkPoint.h" 40 #include "wtf/Assertions.h" 41 42 namespace WebCore { 43 44 // The function types for ScriptItemizeOpenType() and ScriptShapeOpenType(). 45 // We want to use these functions for OpenType feature support, but we can't 46 // call them directly because usp10.dll does not always have them. 47 // Instead, we use GetProcAddress() to check whether we can actually use these 48 // function. If we can't use these functions, we substitute ScriptItemze() and 49 // ScriptShape(). 50 typedef HRESULT (WINAPI *ScriptItemizeOpenTypeFunc)(const WCHAR*, int, int, 51 const SCRIPT_CONTROL*, 52 const SCRIPT_STATE*, 53 SCRIPT_ITEM*, 54 OPENTYPE_TAG*, int*); 55 typedef HRESULT (WINAPI *ScriptShapeOpenTypeFunc)(HDC, SCRIPT_CACHE*, 56 SCRIPT_ANALYSIS*, 57 OPENTYPE_TAG, OPENTYPE_TAG, 58 int*, TEXTRANGE_PROPERTIES**, 59 int, const WCHAR*, int, int, 60 WORD*, SCRIPT_CHARPROP*, 61 WORD*, SCRIPT_GLYPHPROP*, 62 int*); 63 64 static ScriptItemizeOpenTypeFunc gScriptItemizeOpenTypeFunc = 0; 65 static ScriptShapeOpenTypeFunc gScriptShapeOpenTypeFunc = 0; 66 static bool gOpenTypeFunctionsLoaded = false; 67 68 static void loadOpenTypeFunctions() 69 { 70 HMODULE hModule = GetModuleHandle(L"usp10"); 71 if (hModule) { 72 gScriptItemizeOpenTypeFunc = reinterpret_cast<ScriptItemizeOpenTypeFunc>(GetProcAddress(hModule, "ScriptItemizeOpenType")); 73 gScriptShapeOpenTypeFunc = reinterpret_cast<ScriptShapeOpenTypeFunc>(GetProcAddress(hModule, "ScriptShapeOpenType")); 74 } 75 if (!gScriptItemizeOpenTypeFunc || !gScriptShapeOpenTypeFunc) { 76 gScriptItemizeOpenTypeFunc = 0; 77 gScriptShapeOpenTypeFunc = 0; 78 } 79 gOpenTypeFunctionsLoaded = true; 80 } 81 82 enum { 83 FontStyleNormal = 0, 84 FontStyleBold = 1, 85 FontStyleItalic = 2, 86 FontStyleUnderlined = 4 87 }; 88 89 int getStyleFromLogfont(const LOGFONT* logfont) 90 { 91 // FIXME: consider defining UNDEFINED or INVALID for style and 92 // returning it when logfont is 0 93 if (!logfont) { 94 ASSERT_NOT_REACHED(); 95 return FontStyleNormal; 96 } 97 return (logfont->lfItalic ? FontStyleItalic : FontStyleNormal) | 98 (logfont->lfUnderline ? FontStyleUnderlined : FontStyleNormal) | 99 (logfont->lfWeight >= 700 ? FontStyleBold : FontStyleNormal); 100 } 101 102 103 // HFONT is the 'incarnation' of 'everything' about font, but it's an opaque 104 // handle and we can't directly query it to make a new HFONT sharing 105 // its characteristics (height, style, etc) except for family name. 106 // This function uses GetObject to convert HFONT back to LOGFONT, 107 // resets the fields of LOGFONT and calculates style to use later 108 // for the creation of a font identical to HFONT other than family name. 109 static void setLogFontAndStyle(HFONT hfont, LOGFONT *logfont, int *style) 110 { 111 ASSERT(hfont && logfont); 112 if (!hfont || !logfont) 113 return; 114 115 GetObject(hfont, sizeof(LOGFONT), logfont); 116 // We reset these fields to values appropriate for CreateFontIndirect. 117 // while keeping lfHeight, which is the most important value in creating 118 // a new font similar to hfont. 119 logfont->lfWidth = 0; 120 logfont->lfEscapement = 0; 121 logfont->lfOrientation = 0; 122 logfont->lfCharSet = DEFAULT_CHARSET; 123 logfont->lfOutPrecision = OUT_TT_ONLY_PRECIS; 124 logfont->lfQuality = DEFAULT_QUALITY; // Honor user's desktop settings. 125 logfont->lfPitchAndFamily = DEFAULT_PITCH | FF_DONTCARE; 126 if (style) 127 *style = getStyleFromLogfont(logfont); 128 } 129 130 // This memory DC will NOT be released but it's OK 131 // since we want to keep it for the whole life span of the process. 132 HDC UniscribeHelper::m_cachedDC = 0; 133 134 static bool canUseGlyphIndex(const SCRIPT_ITEM& run) 135 { 136 // On early version of Uniscribe, ScriptShape() sets run.a.fNoGlyphIndex 137 // to TRUE when it can't shape the run with glyph indexes. This could 138 // occur when we use CFF webfonts(See http://crbug.com/39017). 139 // We don't use the font in that case and try to use fallback fonts. 140 return !run.a.fNoGlyphIndex; 141 } 142 143 UniscribeHelper::UniscribeHelper(const UChar* input, 144 int inputLength, 145 bool isRtl, 146 HFONT hfont, 147 SCRIPT_CACHE* scriptCache, 148 SCRIPT_FONTPROPERTIES* fontProperties, 149 WORD spaceGlyph) 150 : m_input(input) 151 , m_inputLength(inputLength) 152 , m_isRtl(isRtl) 153 , m_hfont(hfont) 154 , m_scriptCache(scriptCache) 155 , m_fontProperties(fontProperties) 156 , m_spaceGlyph(spaceGlyph) 157 , m_directionalOverride(false) 158 , m_inhibitLigate(false) 159 , m_letterSpacing(0) 160 , m_spaceWidth(0) 161 , m_wordSpacing(0) 162 , m_ascent(0) 163 , m_disableFontFallback(false) 164 165 { 166 m_logfont.lfFaceName[0] = 0; 167 if (!gOpenTypeFunctionsLoaded) 168 loadOpenTypeFunctions(); 169 } 170 171 UniscribeHelper::~UniscribeHelper() 172 { 173 } 174 175 void UniscribeHelper::initWithOptionalLengthProtection(bool lengthProtection) 176 { 177 // We cap the input length and just don't do anything. We'll allocate a lot 178 // of things of the size of the number of characters, so the allocated 179 // memory will be several times the input length. Plus shaping such a large 180 // buffer may be a form of denial of service. No legitimate text should be 181 // this long. It also appears that Uniscribe flatly rejects very long 182 // strings, so we don't lose anything by doing this. 183 // 184 // The input length protection may be disabled by the unit tests to cause 185 // an error condition. 186 static const int kMaxInputLength = 65535; 187 if (m_inputLength == 0 || (lengthProtection && m_inputLength > kMaxInputLength)) 188 return; 189 190 fillRuns(); 191 fillShapes(); 192 fillScreenOrder(); 193 } 194 195 int UniscribeHelper::width() const 196 { 197 int width = 0; 198 for (int itemIndex = 0; itemIndex < static_cast<int>(m_runs.size()); itemIndex++) 199 width += advanceForItem(itemIndex); 200 return width; 201 } 202 203 void UniscribeHelper::justify(int additionalSpace) 204 { 205 // Count the total number of glyphs we have so we know how big to make the 206 // buffers below. 207 int totalGlyphs = 0; 208 for (size_t run = 0; run < m_runs.size(); run++) { 209 int runIndex = m_screenOrder[run]; 210 totalGlyphs += static_cast<int>(m_shapes[runIndex].glyphLength()); 211 } 212 if (totalGlyphs == 0) 213 return; // Nothing to do. 214 215 // We make one big buffer in screen order of all the glyphs we are drawing 216 // across runs so that the justification function will adjust evenly across 217 // all glyphs. 218 Vector<SCRIPT_VISATTR, 64> visualAttributes; 219 visualAttributes.resize(totalGlyphs); 220 Vector<int, 64> advances; 221 advances.resize(totalGlyphs); 222 Vector<int, 64> justify; 223 justify.resize(totalGlyphs); 224 225 // Build the packed input. 226 int destIndex = 0; 227 for (size_t run = 0; run < m_runs.size(); run++) { 228 int runIndex = m_screenOrder[run]; 229 const Shaping& shaping = m_shapes[runIndex]; 230 231 for (int i = 0; i < shaping.glyphLength(); i++, destIndex++) { 232 memcpy(&visualAttributes[destIndex], &shaping.m_visualAttributes[i], 233 sizeof(SCRIPT_VISATTR)); 234 advances[destIndex] = shaping.m_advance[i]; 235 } 236 } 237 238 // The documentation for Scriptjustify is wrong, the parameter is the space 239 // to add and not the width of the column you want. 240 int minKashida; 241 // Disable kashida justification based on 242 // http://blogs.msdn.com/b/michkap/archive/2010/08/31/10056140.aspx. 243 for (int i = 0; i < totalGlyphs; ++i) { 244 if (visualAttributes[i].uJustification == SCRIPT_JUSTIFY_ARABIC_KASHIDA) 245 visualAttributes[i].uJustification = SCRIPT_JUSTIFY_NONE; 246 } 247 minKashida = 0; 248 ScriptJustify(&visualAttributes[0], &advances[0], totalGlyphs, 249 additionalSpace, minKashida, &justify[0]); 250 251 // Now we have to unpack the justification amounts back into the runs so 252 // the glyph indices match. 253 int globalGlyphIndex = 0; 254 for (size_t run = 0; run < m_runs.size(); run++) { 255 int runIndex = m_screenOrder[run]; 256 Shaping& shaping = m_shapes[runIndex]; 257 258 shaping.m_justify.resize(shaping.glyphLength()); 259 for (int i = 0; i < shaping.glyphLength(); i++, globalGlyphIndex++) 260 shaping.m_justify[i] = justify[globalGlyphIndex]; 261 } 262 } 263 264 int UniscribeHelper::characterToX(int offset) const 265 { 266 HRESULT hr; 267 ASSERT(offset <= m_inputLength); 268 269 // Our algorithm is to traverse the items in screen order from left to 270 // right, adding in each item's screen width until we find the item with 271 // the requested character in it. 272 int width = 0; 273 for (size_t screenIndex = 0; screenIndex < m_runs.size(); screenIndex++) { 274 // Compute the length of this run. 275 int itemIndex = m_screenOrder[screenIndex]; 276 const SCRIPT_ITEM& item = m_runs[itemIndex]; 277 const Shaping& shaping = m_shapes[itemIndex]; 278 int itemLength = shaping.charLength(); 279 280 if (offset >= item.iCharPos && offset <= item.iCharPos + itemLength) { 281 // Character offset is in this run. 282 int charLength = offset - item.iCharPos; 283 284 int curX = 0; 285 hr = ScriptCPtoX(charLength, FALSE, itemLength, 286 shaping.glyphLength(), 287 &shaping.m_logs[0], &shaping.m_visualAttributes[0], 288 shaping.effectiveAdvances(), &item.a, &curX); 289 if (FAILED(hr)) 290 return 0; 291 292 width += curX + shaping.m_prePadding; 293 ASSERT(width >= 0); 294 return width; 295 } 296 297 // Move to the next item. 298 width += advanceForItem(itemIndex); 299 } 300 ASSERT(width >= 0); 301 return width; 302 } 303 304 int UniscribeHelper::xToCharacter(int x) const 305 { 306 // We iterate in screen order until we find the item with the given pixel 307 // position in it. When we find that guy, we ask Uniscribe for the 308 // character index. 309 HRESULT hr; 310 for (size_t screenIndex = 0; screenIndex < m_runs.size(); screenIndex++) { 311 int itemIndex = m_screenOrder[screenIndex]; 312 int itemAdvance = advanceForItem(itemIndex); 313 314 // Note that the run may be empty if shaping failed, so we want to skip 315 // over it. 316 const Shaping& shaping = m_shapes[itemIndex]; 317 int itemLength = shaping.charLength(); 318 if (x <= itemAdvance && itemLength > 0) { 319 // The requested offset is within this item. 320 const SCRIPT_ITEM& item = m_runs[itemIndex]; 321 322 // Account for the leading space we've added to this run that 323 // Uniscribe doesn't know about. 324 x -= shaping.m_prePadding; 325 326 int charX = 0; 327 int trailing; 328 hr = ScriptXtoCP(x, itemLength, shaping.glyphLength(), 329 &shaping.m_logs[0], &shaping.m_visualAttributes[0], 330 shaping.effectiveAdvances(), &item.a, &charX, 331 &trailing); 332 333 // The character offset is within the item. We need to add the 334 // item's offset to transform it into the space of the TextRun 335 return charX + item.iCharPos; 336 } 337 338 // The offset is beyond this item, account for its length and move on. 339 x -= itemAdvance; 340 } 341 342 // Error condition, we don't know what to do if we don't have that X 343 // position in any of our items. 344 return 0; 345 } 346 347 void UniscribeHelper::draw(GraphicsContext* graphicsContext, 348 const FontPlatformData& fontPlatformData, HDC dc, int x, int y, 349 const FloatRect& textRect, int from, int to) 350 { 351 HGDIOBJ oldFont = 0; 352 int curX = x; 353 bool firstRun = true; 354 355 for (size_t screenIndex = 0; screenIndex < m_runs.size(); screenIndex++) { 356 int itemIndex = m_screenOrder[screenIndex]; 357 const SCRIPT_ITEM& item = m_runs[itemIndex]; 358 const Shaping& shaping = m_shapes[itemIndex]; 359 360 // Character offsets within this run. THESE MAY NOT BE IN RANGE and may 361 // be negative, etc. The code below handles this. 362 int fromChar = from - item.iCharPos; 363 int toChar = to - item.iCharPos; 364 365 // See if we need to draw any characters in this item. 366 if (shaping.charLength() == 0 || 367 fromChar >= shaping.charLength() || toChar <= 0) { 368 // No chars in this item to display. 369 curX += advanceForItem(itemIndex); 370 continue; 371 } 372 373 // Compute the starting glyph within this span. |from| and |to| are 374 // global offsets that may intersect arbitrarily with our local run. 375 int fromGlyph, afterGlyph; 376 if (item.a.fRTL) { 377 // To compute the first glyph when going RTL, we use |to|. 378 if (toChar >= shaping.charLength()) 379 // The end of the text is after (to the left) of us. 380 fromGlyph = 0; 381 else { 382 // Since |to| is exclusive, the first character we draw on the 383 // left is actually the one right before (to the right) of 384 // |to|. 385 fromGlyph = shaping.m_logs[toChar - 1]; 386 } 387 388 // The last glyph is actually the first character in the range. 389 if (fromChar <= 0) { 390 // The first character to draw is before (to the right) of this 391 // span, so draw all the way to the end. 392 afterGlyph = shaping.glyphLength(); 393 } else { 394 // We want to draw everything up until the character to the 395 // right of |from|. To the right is - 1, so we look that up 396 // (remember our character could be more than one glyph, so we 397 // can't look up our glyph and add one). 398 afterGlyph = shaping.m_logs[fromChar - 1]; 399 } 400 } else { 401 // Easy case, everybody agrees about directions. We only need to 402 // handle boundary conditions to get a range inclusive at the 403 // beginning, and exclusive at the ending. We have to do some 404 // computation to see the glyph one past the end. 405 fromGlyph = shaping.m_logs[fromChar < 0 ? 0 : fromChar]; 406 if (toChar >= shaping.charLength()) 407 afterGlyph = shaping.glyphLength(); 408 else 409 afterGlyph = shaping.m_logs[toChar]; 410 } 411 412 // Account for the characters that were skipped in this run. When 413 // WebKit asks us to draw a subset of the run, it actually tells us 414 // to draw at the X offset of the beginning of the run, since it 415 // doesn't know the internal position of any of our characters. 416 const int* effectiveAdvances = shaping.effectiveAdvances(); 417 int innerOffset = 0; 418 for (int i = 0; i < fromGlyph; i++) 419 innerOffset += effectiveAdvances[i]; 420 421 // Actually draw the glyphs we found. 422 int glyphCount = afterGlyph - fromGlyph; 423 if (fromGlyph >= 0 && glyphCount > 0) { 424 // Account for the preceding space we need to add to this run. We 425 // don't need to count for the following space because that will be 426 // counted in advanceForItem below when we move to the next run. 427 innerOffset += shaping.m_prePadding; 428 429 // Pass 0 in when there is no justification. 430 const int* justify = shaping.m_justify.size() == 0 ? 0 : &shaping.m_justify[fromGlyph]; 431 432 const int* advances = shaping.m_justify.size() ? 433 &shaping.m_justify[fromGlyph] 434 : &shaping.m_advance[fromGlyph]; 435 436 // Fonts with different ascents can be used to render different 437 // runs. 'Across-runs' y-coordinate correction needs to be 438 // adjusted for each font. 439 bool textOutOk = false; 440 for (int executions = 0; executions < 2; ++executions) { 441 SkPoint origin; 442 origin.fX = curX + + innerOffset; 443 origin.fY = y + m_ascent; 444 paintSkiaText(graphicsContext, 445 fontPlatformData, 446 shaping.m_hfont, 447 glyphCount, 448 &shaping.m_glyphs[fromGlyph], 449 advances, 450 &shaping.m_offsets[fromGlyph], 451 origin, 452 textRect); 453 textOutOk = true; 454 455 if (!textOutOk && 0 == executions) { 456 // If TextOut is called from the renderer it might fail 457 // because the sandbox is preventing it from opening the 458 // font files. If we are running in the renderer, 459 // TryToPreloadFont is overridden to ask the browser to 460 // preload the font for us so we can access it. 461 tryToPreloadFont(shaping.m_hfont); 462 continue; 463 } 464 break; 465 } 466 } 467 468 curX += advanceForItem(itemIndex); 469 } 470 471 if (oldFont) 472 SelectObject(dc, oldFont); 473 } 474 475 WORD UniscribeHelper::firstGlyphForCharacter(int charOffset) const 476 { 477 // Find the run for the given character. 478 for (int i = 0; i < static_cast<int>(m_runs.size()); i++) { 479 int firstChar = m_runs[i].iCharPos; 480 const Shaping& shaping = m_shapes[i]; 481 int localOffset = charOffset - firstChar; 482 if (localOffset >= 0 && localOffset < shaping.charLength()) { 483 // The character is in this run, return the first glyph for it 484 // (should generally be the only glyph). It seems Uniscribe gives 485 // glyph 0 for empty, which is what we want to return in the 486 // "missing" case. 487 size_t glyphIndex = shaping.m_logs[localOffset]; 488 if (glyphIndex >= shaping.m_glyphs.size()) { 489 // The glyph should be in this run, but the run has too few 490 // actual characters. This can happen when shaping the run 491 // fails, in which case, we should have no data in the logs at 492 // all. 493 ASSERT(shaping.m_glyphs.size() == 0); 494 return 0; 495 } 496 return shaping.m_glyphs[glyphIndex]; 497 } 498 } 499 500 return 0; 501 } 502 503 void UniscribeHelper::fillRuns() 504 { 505 HRESULT hr; 506 m_runs.resize(cUniscribeHelperStackRuns); 507 m_scriptTags.resize(cUniscribeHelperStackRuns); 508 509 SCRIPT_STATE inputState; 510 inputState.uBidiLevel = m_isRtl; 511 inputState.fOverrideDirection = m_directionalOverride; 512 inputState.fInhibitSymSwap = false; 513 inputState.fCharShape = false; // Not implemented in Uniscribe 514 inputState.fDigitSubstitute = false; // Do we want this for Arabic? 515 inputState.fInhibitLigate = m_inhibitLigate; 516 inputState.fDisplayZWG = false; // Don't draw control characters. 517 inputState.fArabicNumContext = m_isRtl; // Do we want this for Arabic? 518 inputState.fGcpClusters = false; 519 inputState.fReserved = 0; 520 inputState.fEngineReserved = 0; 521 // The psControl argument to ScriptItemize should be non-0 for RTL text, 522 // per http://msdn.microsoft.com/en-us/library/ms776532.aspx . So use a 523 // SCRIPT_CONTROL that is set to all zeros. Zero as a locale ID means the 524 // neutral locale per http://msdn.microsoft.com/en-us/library/ms776294.aspx 525 static SCRIPT_CONTROL inputControl = {0, // uDefaultLanguage :16; 526 0, // fContextDigits :1; 527 0, // fInvertPreBoundDir :1; 528 0, // fInvertPostBoundDir :1; 529 0, // fLinkStringBefore :1; 530 0, // fLinkStringAfter :1; 531 0, // fNeutralOverride :1; 532 0, // fNumericOverride :1; 533 0, // fLegacyBidiClass :1; 534 0, // fMergeNeutralItems :1; 535 0};// fReserved :7; 536 // Calling ScriptApplyDigitSubstitution( 0, &inputControl, &inputState) 537 // here would be appropriate if we wanted to set the language ID, and get 538 // local digit substitution behavior. For now, don't do it. 539 540 while (true) { 541 int numberOfItems = 0; 542 543 // Ideally, we would have a way to know the runs before and after this 544 // one, and put them into the control parameter of ScriptItemize. This 545 // would allow us to shape characters properly that cross style 546 // boundaries (WebKit bug 6148). 547 // 548 // We tell ScriptItemize that the output list of items is one smaller 549 // than it actually is. According to Mozilla bug 366643, if there is 550 // not enough room in the array on pre-SP2 systems, ScriptItemize will 551 // write one past the end of the buffer. 552 // 553 // ScriptItemize is very strange. It will often require a much larger 554 // ITEM buffer internally than it will give us as output. For example, 555 // it will say a 16-item buffer is not big enough, and will write 556 // interesting numbers into all those items. But when we give it a 32 557 // item buffer and it succeeds, it only has one item output. 558 // 559 // It seems to be doing at least two passes, the first where it puts a 560 // lot of intermediate data into our items, and the second where it 561 // collates them. 562 if (gScriptItemizeOpenTypeFunc) { 563 hr = gScriptItemizeOpenTypeFunc(m_input, m_inputLength, 564 static_cast<int>(m_runs.size()) - 1, 565 &inputControl, &inputState, 566 &m_runs[0], &m_scriptTags[0], 567 &numberOfItems); 568 569 if (SUCCEEDED(hr)) { 570 // Pack consecutive runs, the script tag of which are 571 // SCRIPT_TAG_UNKNOWN, to reduce the number of runs. 572 for (int i = 0; i < numberOfItems; ++i) { 573 // Do not pack with whitespace characters at the head. 574 // Otherwise whole the run is rendered as a whitespace. 575 WCHAR ch = m_input[m_runs[i].iCharPos]; 576 if (m_scriptTags[i] == SCRIPT_TAG_UNKNOWN && !Font::treatAsSpace(ch) && !Font::treatAsZeroWidthSpace(ch)) { 577 int j = 1; 578 while (i + j < numberOfItems && m_scriptTags[i + j] == SCRIPT_TAG_UNKNOWN) 579 ++j; 580 if (--j) { 581 m_runs.remove(i + 1, j); 582 m_scriptTags.remove(i + 1, j); 583 numberOfItems -= j; 584 } 585 } 586 } 587 m_scriptTags.resize(numberOfItems); 588 } 589 } else { 590 hr = ScriptItemize(m_input, m_inputLength, 591 static_cast<int>(m_runs.size()) - 1, 592 &inputControl, &inputState, &m_runs[0], 593 &numberOfItems); 594 } 595 if (SUCCEEDED(hr)) { 596 m_runs.resize(numberOfItems); 597 break; 598 } 599 if (hr != E_OUTOFMEMORY) { 600 // Some kind of unexpected error. 601 m_runs.resize(0); 602 break; 603 } 604 // There was not enough items for it to write into, expand. 605 m_runs.resize(m_runs.size() * 2); 606 m_scriptTags.resize(m_runs.size()); 607 } 608 } 609 610 const int kUndefinedAscent = std::numeric_limits<int>::min(); 611 612 // Given an HFONT, return the ascent. If GetTextMetrics fails, 613 // kUndefinedAscent is returned, instead. 614 int getAscent(HFONT hfont) 615 { 616 HWndDC dc(0); 617 HGDIOBJ oldFont = SelectObject(dc, hfont); 618 TEXTMETRIC tm; 619 BOOL gotMetrics = GetTextMetrics(dc, &tm); 620 SelectObject(dc, oldFont); 621 return gotMetrics ? tm.tmAscent : kUndefinedAscent; 622 } 623 624 const WORD kUnsupportedGlyph = 0xffff; 625 626 WORD getSpaceGlyph(HFONT hfont) 627 { 628 HWndDC dc(0); 629 HGDIOBJ oldFont = SelectObject(dc, hfont); 630 WCHAR space = L' '; 631 WORD spaceGlyph = kUnsupportedGlyph; 632 GetGlyphIndices(dc, &space, 1, &spaceGlyph, GGI_MARK_NONEXISTING_GLYPHS); 633 SelectObject(dc, oldFont); 634 return spaceGlyph; 635 } 636 637 struct ShaperFontData { 638 ShaperFontData() 639 : hfont(0) 640 , ascent(kUndefinedAscent) 641 , scriptCache(0) 642 , spaceGlyph(0) 643 { 644 } 645 646 HFONT hfont; 647 int ascent; 648 mutable SCRIPT_CACHE scriptCache; 649 WORD spaceGlyph; 650 }; 651 652 // Again, using hash_map does not earn us much here. page_cycler_test intl2 653 // gave us a 'better' result with map than with hash_map even though they're 654 // well-within 1-sigma of each other so that the difference is not significant. 655 // On the other hand, some pages in intl2 seem to take longer to load with map 656 // in the 1st pass. Need to experiment further. 657 typedef HashMap<String, ShaperFontData> ShaperFontDataCache; 658 659 // Derive a new HFONT by replacing lfFaceName of LOGFONT with |family|, 660 // calculate the ascent for the derived HFONT, and initialize SCRIPT_CACHE 661 // in ShaperFontData. 662 // |style| is only used for cache key generation. |style| is 663 // bit-wise OR of BOLD(1), UNDERLINED(2) and ITALIC(4) and 664 // should match what's contained in LOGFONT. It should be calculated 665 // by calling GetStyleFromLogFont. 666 // Returns false if the font is not accessible, in which case |ascent| field 667 // of |ShaperFontData| is set to kUndefinedAscent. 668 // Be aware that this is not thread-safe. 669 // FIXME: Instead of having three out params, we'd better have one 670 // (|*ShaperFontData|), but somehow it mysteriously messes up the layout for 671 // certain complex script pages (e.g. hi.wikipedia.org) and also crashes 672 // at the start-up if recently visited page list includes pages with complex 673 // scripts in their title. Moreover, somehow the very first-pass of 674 // intl2 page-cycler test is noticeably slower with one out param than 675 // the current version although the subsequent 9 passes take about the 676 // same time. 677 // Be aware that this is not thread-safe. 678 static bool getDerivedFontData(const UChar* family, int style, LOGFONT* logfont, 679 int* ascent, HFONT* hfont, SCRIPT_CACHE** scriptCache, WORD* spaceGlyph) 680 { 681 ASSERT(logfont); 682 ASSERT(family); 683 ASSERT(*family); 684 685 // It does not matter that we leak font data when we exit. 686 static ShaperFontDataCache* gFontDataCache = 0; 687 if (!gFontDataCache) 688 gFontDataCache = new ShaperFontDataCache(); 689 690 // FIXME: This comes up pretty high in the profile so that 691 // we need to measure whether using SHA256 (after coercing all the 692 // fields to char*) is faster than String::format. 693 String fontKey = String::format("%1d:%d:%ls", style, logfont->lfHeight, family); 694 ShaperFontDataCache::iterator iter = gFontDataCache->find(fontKey); 695 ShaperFontData* derived; 696 if (iter == gFontDataCache->end()) { 697 ASSERT(wcslen(family) < LF_FACESIZE); 698 wcscpy_s(logfont->lfFaceName, LF_FACESIZE, family); 699 // FIXME: CreateFontIndirect always comes up with 700 // a font even if there's no font matching the name. Need to 701 // check it against what we actually want (as is done in 702 // FontCacheWin.cpp) 703 ShaperFontDataCache::AddResult entry = gFontDataCache->add(fontKey, ShaperFontData()); 704 derived = &entry.iterator->value; 705 derived->hfont = CreateFontIndirect(logfont); 706 // GetAscent may return kUndefinedAscent, but we still want to 707 // cache it so that we won't have to call CreateFontIndirect once 708 // more for HFONT next time. 709 derived->ascent = getAscent(derived->hfont); 710 derived->spaceGlyph = getSpaceGlyph(derived->hfont); 711 } else { 712 derived = &iter->value; 713 // Last time, getAscent or getSpaceGlyph failed so that only HFONT was 714 // cached. Try once more assuming that TryPreloadFont 715 // was called by a caller between calls. 716 if (kUndefinedAscent == derived->ascent) 717 derived->ascent = getAscent(derived->hfont); 718 if (kUnsupportedGlyph == derived->spaceGlyph) 719 derived->spaceGlyph = getSpaceGlyph(derived->hfont); 720 } 721 *hfont = derived->hfont; 722 *ascent = derived->ascent; 723 *scriptCache = &(derived->scriptCache); 724 *spaceGlyph = derived->spaceGlyph; 725 return *ascent != kUndefinedAscent && *spaceGlyph != kUnsupportedGlyph; 726 } 727 728 bool UniscribeHelper::shape(const UChar* input, 729 int itemLength, 730 int numGlyphs, 731 SCRIPT_ITEM& run, 732 OPENTYPE_TAG scriptTag, 733 Shaping& shaping) 734 { 735 HFONT hfont = m_hfont; 736 SCRIPT_CACHE* scriptCache = m_scriptCache; 737 SCRIPT_FONTPROPERTIES* fontProperties = m_fontProperties; 738 Vector<SCRIPT_CHARPROP, cUniscribeHelperStackChars> charProps; 739 Vector<SCRIPT_GLYPHPROP, cUniscribeHelperStackChars> glyphProps; 740 int ascent = m_ascent; 741 WORD spaceGlyph = m_spaceGlyph; 742 HRESULT hr; 743 // When used to fill up glyph pages for simple scripts in non-BMP, 744 // we don't want any font fallback in this class. The simple script 745 // font path can take care of font fallback. 746 bool lastFallbackTried = m_disableFontFallback; 747 bool result; 748 749 int generatedGlyphs = 0; 750 751 // In case HFONT passed in ctor cannot render this run, we have to scan 752 // other fonts from the beginning of the font list. 753 resetFontIndex(); 754 755 // Compute shapes. 756 while (true) { 757 shaping.m_logs.resize(itemLength); 758 shaping.m_glyphs.resize(numGlyphs); 759 shaping.m_visualAttributes.resize(numGlyphs); 760 charProps.resize(itemLength); 761 glyphProps.resize(numGlyphs); 762 run.a.fNoGlyphIndex = FALSE; 763 764 #ifdef PURIFY 765 // http://code.google.com/p/chromium/issues/detail?id=5309 766 // Purify isn't able to track the assignments that ScriptShape makes to 767 // shaping.m_glyphs. Consequently, any bytes with value 0xCD that it 768 // writes, will be considered un-initialized data. 769 // 770 // This hack avoid the false-positive UMRs by marking the buffer as 771 // initialized. 772 // 773 // FIXME: A better solution would be to use Purify's API and mark only 774 // the populated range as initialized: 775 // 776 // PurifyMarkAsInitialized( 777 // &shaping.m_glyphs[0], 778 // sizeof(shaping.m_glyphs[0] * generatedGlyphs); 779 780 ZeroMemory(&shaping.m_glyphs[0], 781 sizeof(shaping.m_glyphs[0]) * shaping.m_glyphs.size()); 782 #endif 783 // If our DC is already created, select the font in it so we can use it now. 784 // Otherwise, we'll create it as needed afterward... 785 if (m_cachedDC) 786 SelectObject(m_cachedDC, hfont); 787 788 // Firefox sets SCRIPT_ANALYSIS.SCRIPT_STATE.fDisplayZWG to true 789 // here. Is that what we want? It will display control characters. 790 if (gScriptShapeOpenTypeFunc) { 791 TEXTRANGE_PROPERTIES* rangeProps = m_featureRecords.size() ? &m_rangeProperties : 0; 792 hr = gScriptShapeOpenTypeFunc(m_cachedDC, scriptCache, &run.a, 793 scriptTag, 0, &itemLength, 794 &rangeProps, rangeProps ? 1 : 0, 795 input, itemLength, numGlyphs, 796 &shaping.m_logs[0], &charProps[0], 797 &shaping.m_glyphs[0], &glyphProps[0], 798 &generatedGlyphs); 799 if (SUCCEEDED(hr)) { 800 // If we use ScriptShapeOpenType(), visual attributes 801 // information for each characters are stored in 802 // |glyphProps[i].sva|. 803 for (int i = 0; i < generatedGlyphs; ++i) 804 memcpy(&shaping.m_visualAttributes[i], &glyphProps[i].sva, sizeof(SCRIPT_VISATTR)); 805 } 806 } else { 807 hr = ScriptShape(m_cachedDC, scriptCache, input, itemLength, 808 numGlyphs, &run.a, 809 &shaping.m_glyphs[0], &shaping.m_logs[0], 810 &shaping.m_visualAttributes[0], &generatedGlyphs); 811 } 812 // We receive E_PENDING when we need to try again with a Drawing Context, 813 // but we don't want to retry again if we already tried with non-zero DC. 814 if (hr == E_PENDING && !m_cachedDC) { 815 EnsureCachedDCCreated(); 816 continue; 817 } 818 if (hr == E_OUTOFMEMORY) { 819 numGlyphs *= 2; 820 continue; 821 } 822 if (SUCCEEDED(hr) && (lastFallbackTried || !containsMissingGlyphs(shaping, run, fontProperties) && canUseGlyphIndex(run))) 823 break; 824 825 // The current font can't render this run, try next font. 826 if (!m_disableFontFallback && 827 nextWinFontData(hfont, scriptCache, fontProperties, ascent, spaceGlyph)) { 828 // The primary font does not support this run. Try next font. 829 // In case of web page rendering, they come from fonts specified in 830 // CSS stylesheets. 831 continue; 832 } else if (!lastFallbackTried) { 833 lastFallbackTried = true; 834 835 // Generate a last fallback font based on the script of 836 // a character to draw while inheriting size and styles 837 // from the primary font 838 if (!m_logfont.lfFaceName[0]) 839 setLogFontAndStyle(m_hfont, &m_logfont, &m_style); 840 841 // TODO(jungshik): generic type should come from webkit for 842 // UniscribeHelperTextRun (a derived class used in webkit). 843 const UChar *family = getFallbackFamilyForFirstNonCommonCharacter(input, itemLength, 844 FontDescription::StandardFamily); 845 bool fontOk = getDerivedFontData(family, m_style, &m_logfont, 846 &ascent, &hfont, &scriptCache, 847 &spaceGlyph); 848 849 850 if (!fontOk) { 851 // If this GetDerivedFontData is called from the renderer it 852 // might fail because the sandbox is preventing it from opening 853 // the font files. If we are running in the renderer, 854 // TryToPreloadFont is overridden to ask the browser to preload 855 // the font for us so we can access it. 856 tryToPreloadFont(hfont); 857 858 // Try again. 859 fontOk = getDerivedFontData(family, m_style, &m_logfont, 860 &ascent, &hfont, &scriptCache, 861 &spaceGlyph); 862 ASSERT(fontOk); 863 } 864 865 // TODO(jungshik) : Currently GetDerivedHFont always returns a 866 // a valid HFONT, but in the future, I may change it to return 0. 867 ASSERT(hfont); 868 869 // We don't need a font_properties for the last resort fallback font 870 // because we don't have anything more to try and are forced to 871 // accept empty glyph boxes. If we tried a series of fonts as 872 // 'last-resort fallback', we'd need it, but currently, we don't. 873 continue; 874 } else if (hr == USP_E_SCRIPT_NOT_IN_FONT) { 875 run.a.eScript = SCRIPT_UNDEFINED; 876 continue; 877 } else if (FAILED(hr)) { 878 // Error shaping. 879 generatedGlyphs = 0; 880 result = false; 881 goto cleanup; 882 } 883 } 884 885 // Sets Windows font data for this run to those corresponding to 886 // a font supporting this run. we don't need to store font_properties 887 // because it's not used elsewhere. 888 shaping.m_hfont = hfont; 889 shaping.m_scriptCache = scriptCache; 890 shaping.m_spaceGlyph = spaceGlyph; 891 892 // The ascent of a font for this run can be different from 893 // that of the primary font so that we need to keep track of 894 // the difference per run and take that into account when calling 895 // ScriptTextOut in |draw|. Otherwise, different runs rendered by 896 // different fonts would not be aligned vertically. 897 shaping.m_ascentOffset = m_ascent ? ascent - m_ascent : 0; 898 result = true; 899 900 cleanup: 901 shaping.m_glyphs.resize(generatedGlyphs); 902 shaping.m_visualAttributes.resize(generatedGlyphs); 903 shaping.m_advance.resize(generatedGlyphs); 904 shaping.m_offsets.resize(generatedGlyphs); 905 906 // On failure, our logs don't mean anything, so zero those out. 907 if (!result) 908 shaping.m_logs.clear(); 909 910 return result; 911 } 912 913 void UniscribeHelper::EnsureCachedDCCreated() 914 { 915 if (m_cachedDC) 916 return; 917 // Allocate a memory DC that is compatible with the Desktop DC since we don't have any window, 918 // and we don't want to use the Desktop DC directly since it can have nasty side effects 919 // as identified in Chrome Issue http://crbug.com/59315. 920 HWndDC screenDC(0); 921 m_cachedDC = ::CreateCompatibleDC(screenDC); 922 ASSERT(m_cachedDC); 923 } 924 925 void UniscribeHelper::fillShapes() 926 { 927 m_shapes.resize(m_runs.size()); 928 for (size_t i = 0; i < m_runs.size(); i++) { 929 int startItem = m_runs[i].iCharPos; 930 int itemLength = m_inputLength - startItem; 931 if (i < m_runs.size() - 1) 932 itemLength = m_runs[i + 1].iCharPos - startItem; 933 934 int numGlyphs; 935 if (itemLength < cUniscribeHelperStackChars) { 936 // We'll start our buffer sizes with the current stack space 937 // available in our buffers if the current input fits. As long as 938 // it doesn't expand past that we'll save a lot of time mallocing. 939 numGlyphs = cUniscribeHelperStackChars; 940 } else { 941 // When the input doesn't fit, give up with the stack since it will 942 // almost surely not be enough room (unless the input actually 943 // shrinks, which is unlikely) and just start with the length 944 // recommended by the Uniscribe documentation as a "usually fits" 945 // size. 946 numGlyphs = itemLength * 3 / 2 + 16; 947 } 948 949 // Convert a string to a glyph string trying the primary font, fonts in 950 // the fallback list and then script-specific last resort font. 951 Shaping& shaping = m_shapes[i]; 952 if (!shape(&m_input[startItem], itemLength, numGlyphs, m_runs[i], m_scriptTags[i], shaping)) 953 continue; 954 955 // At the moment, the only time m_disableFontFallback is set is 956 // when we look up glyph indices for non-BMP code ranges. So, 957 // we can skip the glyph placement. When that becomes not the case 958 // any more, we have to add a new flag to control glyph placement. 959 if (m_disableFontFallback) 960 continue; 961 962 // Compute placements. Note that offsets is documented incorrectly 963 // and is actually an array. 964 EnsureCachedDCCreated(); 965 SelectObject(m_cachedDC, shaping.m_hfont); 966 shaping.m_prePadding = 0; 967 if (FAILED(ScriptPlace(m_cachedDC, shaping.m_scriptCache, 968 &shaping.m_glyphs[0], 969 static_cast<int>(shaping.m_glyphs.size()), 970 &shaping.m_visualAttributes[0], &m_runs[i].a, 971 &shaping.m_advance[0], &shaping.m_offsets[0], 972 &shaping.m_abc))) { 973 // Some error we don't know how to handle. Nuke all of our data 974 // since we can't deal with partially valid data later. 975 m_runs.clear(); 976 m_scriptTags.clear(); 977 m_shapes.clear(); 978 m_screenOrder.clear(); 979 } 980 } 981 982 adjustSpaceAdvances(); 983 984 if (m_letterSpacing != 0 || m_wordSpacing != 0) 985 applySpacing(); 986 } 987 988 void UniscribeHelper::fillScreenOrder() 989 { 990 m_screenOrder.resize(m_runs.size()); 991 992 // We assume that the input has only one text direction in it. 993 // TODO(brettw) are we sure we want to keep this restriction? 994 if (m_isRtl) { 995 for (int i = 0; i < static_cast<int>(m_screenOrder.size()); i++) 996 m_screenOrder[static_cast<int>(m_screenOrder.size()) - i - 1] = i; 997 } else { 998 for (int i = 0; i < static_cast<int>(m_screenOrder.size()); i++) 999 m_screenOrder[i] = i; 1000 } 1001 } 1002 1003 void UniscribeHelper::adjustSpaceAdvances() 1004 { 1005 if (m_spaceWidth == 0) 1006 return; 1007 1008 int spaceWidthWithoutLetterSpacing = m_spaceWidth - m_letterSpacing; 1009 1010 // This mostly matches what WebKit's UniscribeController::shapeAndPlaceItem. 1011 for (size_t run = 0; run < m_runs.size(); run++) { 1012 Shaping& shaping = m_shapes[run]; 1013 1014 // FIXME: This loop is not UTF-16-safe. Unicode 6.0 has a couple 1015 // of complex script blocks in Plane 1. 1016 for (int i = 0; i < shaping.charLength(); i++) { 1017 UChar c = m_input[m_runs[run].iCharPos + i]; 1018 bool treatAsSpace = Font::treatAsSpace(c); 1019 if (!treatAsSpace && !Font::treatAsZeroWidthSpaceInComplexScript(c)) 1020 continue; 1021 1022 int glyphIndex = shaping.m_logs[i]; 1023 int currentAdvance = shaping.m_advance[glyphIndex]; 1024 1025 shaping.m_glyphs[glyphIndex] = shaping.m_spaceGlyph; 1026 1027 if (treatAsSpace) { 1028 // currentAdvance does not include additional letter-spacing, 1029 // but m_spaceWidth does. Here we find out how off we are from 1030 // the correct width (spaceWidthWithoutLetterSpacing) and 1031 // just subtract that diff. 1032 int diff = currentAdvance - spaceWidthWithoutLetterSpacing; 1033 // The shaping can consist of a run of text, so only subtract 1034 // the difference in the width of the glyph. 1035 shaping.m_advance[glyphIndex] -= diff; 1036 shaping.m_abc.abcB -= diff; 1037 continue; 1038 } 1039 1040 // For characters treated as zero-width space in complex 1041 // scripts, set the advance width to zero, adjust 1042 // |abcB| of the current run accordingly and set 1043 // the glyph to m_spaceGlyph (invisible). 1044 shaping.m_advance[glyphIndex] = 0; 1045 shaping.m_abc.abcB -= currentAdvance; 1046 shaping.m_offsets[glyphIndex].du = 0; 1047 shaping.m_offsets[glyphIndex].dv = 0; 1048 } 1049 } 1050 } 1051 1052 void UniscribeHelper::applySpacing() 1053 { 1054 for (size_t run = 0; run < m_runs.size(); run++) { 1055 Shaping& shaping = m_shapes[run]; 1056 bool isRtl = m_runs[run].a.fRTL; 1057 1058 if (m_letterSpacing != 0) { 1059 // RTL text gets padded to the left of each character. We increment 1060 // the run's advance to make this happen. This will be balanced out 1061 // by NOT adding additional advance to the last glyph in the run. 1062 if (isRtl) 1063 shaping.m_prePadding += m_letterSpacing; 1064 1065 // Go through all the glyphs in this run and increase the "advance" 1066 // to account for letter spacing. We adjust letter spacing only on 1067 // cluster boundaries. 1068 // 1069 // This works for most scripts, but may have problems with some 1070 // indic scripts. This behavior is better than Firefox or IE for 1071 // Hebrew. 1072 for (int i = 0; i < shaping.glyphLength(); i++) { 1073 if (shaping.m_visualAttributes[i].fClusterStart) { 1074 // Ick, we need to assign the extra space so that the glyph 1075 // comes first, then is followed by the space. This is 1076 // opposite for RTL. 1077 if (isRtl) { 1078 if (i != shaping.glyphLength() - 1) { 1079 // All but the last character just get the spacing 1080 // applied to their advance. The last character 1081 // doesn't get anything, 1082 shaping.m_advance[i] += m_letterSpacing; 1083 shaping.m_abc.abcB += m_letterSpacing; 1084 } 1085 } else { 1086 // LTR case is easier, we just add to the advance. 1087 shaping.m_advance[i] += m_letterSpacing; 1088 shaping.m_abc.abcB += m_letterSpacing; 1089 } 1090 } 1091 } 1092 } 1093 1094 // Go through all the characters to find whitespace and insert the 1095 // extra wordspacing amount for the glyphs they correspond to. 1096 if (m_wordSpacing != 0) { 1097 for (int i = 0; i < shaping.charLength(); i++) { 1098 if (!Font::treatAsSpace(m_input[m_runs[run].iCharPos + i])) 1099 continue; 1100 1101 // The char in question is a word separator... 1102 int glyphIndex = shaping.m_logs[i]; 1103 1104 // Spaces will not have a glyph in Uniscribe, it will just add 1105 // additional advance to the character to the left of the 1106 // space. The space's corresponding glyph will be the character 1107 // following it in reading order. 1108 if (isRtl) { 1109 // In RTL, the glyph to the left of the space is the same 1110 // as the first glyph of the following character, so we can 1111 // just increment it. 1112 shaping.m_advance[glyphIndex] += m_wordSpacing; 1113 shaping.m_abc.abcB += m_wordSpacing; 1114 } else { 1115 // LTR is actually more complex here, we apply it to the 1116 // previous character if there is one, otherwise we have to 1117 // apply it to the leading space of the run. 1118 if (glyphIndex == 0) 1119 shaping.m_prePadding += m_wordSpacing; 1120 else { 1121 shaping.m_advance[glyphIndex - 1] += m_wordSpacing; 1122 shaping.m_abc.abcB += m_wordSpacing; 1123 } 1124 } 1125 } 1126 } // m_wordSpacing != 0 1127 1128 // Loop for next run... 1129 } 1130 } 1131 1132 // The advance is the ABC width of the run 1133 int UniscribeHelper::advanceForItem(int itemIndex) const 1134 { 1135 int accum = 0; 1136 const Shaping& shaping = m_shapes[itemIndex]; 1137 1138 if (shaping.m_justify.size() == 0) { 1139 // Easy case with no justification, the width is just the ABC width of 1140 // the run. (The ABC width is the sum of the advances). 1141 return shaping.m_abc.abcA + shaping.m_abc.abcB + 1142 shaping.m_abc.abcC + shaping.m_prePadding; 1143 } 1144 1145 // With justification, we use the justified amounts instead. The 1146 // justification array contains both the advance and the extra space 1147 // added for justification, so is the width we want. 1148 int justification = 0; 1149 for (size_t i = 0; i < shaping.m_justify.size(); i++) 1150 justification += shaping.m_justify[i]; 1151 1152 return shaping.m_prePadding + justification; 1153 } 1154 1155 // SCRIPT_FONTPROPERTIES contains glyph indices for default, invalid 1156 // and blank glyphs. Just because ScriptShape succeeds does not mean 1157 // that a text run is rendered correctly. Some characters may be rendered 1158 // with default/invalid/blank glyphs. Therefore, we need to check if the glyph 1159 // array returned by ScriptShape contains any of those glyphs to make 1160 // sure that the text run is rendered successfully. 1161 // However, we should not subject zero-width characters to this test. 1162 1163 bool UniscribeHelper::containsMissingGlyphs(const Shaping& shaping, 1164 const SCRIPT_ITEM& run, 1165 const SCRIPT_FONTPROPERTIES* properties) const 1166 { 1167 for (int i = 0; i < shaping.charLength(); i++) { 1168 UChar c = m_input[run.iCharPos + i]; 1169 // Skip zero-width space characters because they're not considered to 1170 // be missing in a font. 1171 if (Font::treatAsZeroWidthSpaceInComplexScript(c)) 1172 continue; 1173 int glyphIndex = shaping.m_logs[i]; 1174 WORD glyph = shaping.m_glyphs[glyphIndex]; 1175 // Note on the thrid condition: Windows Vista sometimes returns glyphs 1176 // equal to wgBlank (instead of wgDefault), with fZeroWidth set. Treat 1177 // such cases as having missing glyphs if the corresponding character 1178 // is not a zero width whitespace. 1179 if (glyph == properties->wgDefault 1180 || (glyph == properties->wgInvalid && glyph != properties->wgBlank) 1181 || (glyph == properties->wgBlank && shaping.m_visualAttributes[glyphIndex].fZeroWidth && !Font::treatAsZeroWidthSpace(c))) 1182 return true; 1183 } 1184 return false; 1185 } 1186 1187 static OPENTYPE_TAG convertFeatureTag(const String& tag) 1188 { 1189 return ((tag[0] & 0xFF) | ((tag[1] & 0xFF) << 8) | ((tag[2] & 0xFF) << 16) | ((tag[3] & 0xFF) << 24)); 1190 } 1191 1192 void UniscribeHelper::setRangeProperties(const FontFeatureSettings* featureSettings) 1193 { 1194 if (!featureSettings || !featureSettings->size()) { 1195 m_featureRecords.resize(0); 1196 return; 1197 } 1198 1199 m_featureRecords.resize(featureSettings->size()); 1200 for (unsigned i = 0; i < featureSettings->size(); ++i) { 1201 m_featureRecords[i].lParameter = featureSettings->at(i).value(); 1202 m_featureRecords[i].tagFeature = convertFeatureTag(featureSettings->at(i).tag()); 1203 } 1204 m_rangeProperties.potfRecords = &m_featureRecords[0]; 1205 m_rangeProperties.cotfRecords = m_featureRecords.size(); 1206 } 1207 1208 } // namespace WebCore 1209
