1 /* 2 * Copyright (C) 1999 Lars Knoll (knoll (at) kde.org) 3 * (C) 1999 Antti Koivisto (koivisto (at) kde.org) 4 * (C) 2000 Dirk Mueller (mueller (at) kde.org) 5 * Copyright (C) 2003, 2006, 2010, 2011 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 24 #include "config.h" 25 #include "platform/fonts/Font.h" 26 27 #include "platform/LayoutUnit.h" 28 #include "platform/RuntimeEnabledFeatures.h" 29 #include "platform/fonts/Character.h" 30 #include "platform/fonts/FontCache.h" 31 #include "platform/fonts/FontFallbackList.h" 32 #include "platform/fonts/FontPlatformFeatures.h" 33 #include "platform/fonts/GlyphBuffer.h" 34 #include "platform/fonts/GlyphPageTreeNode.h" 35 #include "platform/fonts/SimpleFontData.h" 36 #include "platform/fonts/WidthIterator.h" 37 #include "platform/geometry/FloatRect.h" 38 #include "platform/graphics/GraphicsContext.h" 39 #include "platform/text/TextRun.h" 40 #include "wtf/MainThread.h" 41 #include "wtf/StdLibExtras.h" 42 #include "wtf/unicode/CharacterNames.h" 43 #include "wtf/unicode/Unicode.h" 44 45 using namespace WTF; 46 using namespace Unicode; 47 48 namespace blink { 49 50 CodePath Font::s_codePath = AutoPath; 51 52 // ============================================================================================ 53 // Font Implementation (Cross-Platform Portion) 54 // ============================================================================================ 55 56 Font::Font() 57 { 58 } 59 60 Font::Font(const FontDescription& fd) 61 : m_fontDescription(fd) 62 { 63 } 64 65 Font::Font(const Font& other) 66 : m_fontDescription(other.m_fontDescription) 67 , m_fontFallbackList(other.m_fontFallbackList) 68 { 69 } 70 71 Font& Font::operator=(const Font& other) 72 { 73 m_fontDescription = other.m_fontDescription; 74 m_fontFallbackList = other.m_fontFallbackList; 75 return *this; 76 } 77 78 bool Font::operator==(const Font& other) const 79 { 80 // Our FontData don't have to be checked, since checking the font description will be fine. 81 // FIXME: This does not work if the font was made with the FontPlatformData constructor. 82 if (loadingCustomFonts() || other.loadingCustomFonts()) 83 return false; 84 85 FontSelector* first = m_fontFallbackList ? m_fontFallbackList->fontSelector() : 0; 86 FontSelector* second = other.m_fontFallbackList ? other.m_fontFallbackList->fontSelector() : 0; 87 88 return first == second 89 && m_fontDescription == other.m_fontDescription 90 && (m_fontFallbackList ? m_fontFallbackList->fontSelectorVersion() : 0) == (other.m_fontFallbackList ? other.m_fontFallbackList->fontSelectorVersion() : 0) 91 && (m_fontFallbackList ? m_fontFallbackList->generation() : 0) == (other.m_fontFallbackList ? other.m_fontFallbackList->generation() : 0); 92 } 93 94 void Font::update(PassRefPtrWillBeRawPtr<FontSelector> fontSelector) const 95 { 96 // FIXME: It is pretty crazy that we are willing to just poke into a RefPtr, but it ends up 97 // being reasonably safe (because inherited fonts in the render tree pick up the new 98 // style anyway. Other copies are transient, e.g., the state in the GraphicsContext, and 99 // won't stick around long enough to get you in trouble). Still, this is pretty disgusting, 100 // and could eventually be rectified by using RefPtrs for Fonts themselves. 101 if (!m_fontFallbackList) 102 m_fontFallbackList = FontFallbackList::create(); 103 m_fontFallbackList->invalidate(fontSelector); 104 } 105 106 float Font::drawText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const FloatPoint& point, CustomFontNotReadyAction customFontNotReadyAction) const 107 { 108 // Don't draw anything while we are using custom fonts that are in the process of loading, 109 // except if the 'force' argument is set to true (in which case it will use a fallback 110 // font). 111 if (shouldSkipDrawing() && customFontNotReadyAction == DoNotPaintIfFontNotReady) 112 return 0; 113 114 CodePath codePathToUse = codePath(runInfo.run); 115 // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050 116 if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length())) 117 codePathToUse = ComplexPath; 118 119 if (codePathToUse != ComplexPath) 120 return drawSimpleText(context, runInfo, point); 121 122 return drawComplexText(context, runInfo, point); 123 } 124 125 void Font::drawEmphasisMarks(GraphicsContext* context, const TextRunPaintInfo& runInfo, const AtomicString& mark, const FloatPoint& point) const 126 { 127 if (shouldSkipDrawing()) 128 return; 129 130 CodePath codePathToUse = codePath(runInfo.run); 131 // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050 132 if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length())) 133 codePathToUse = ComplexPath; 134 135 if (codePathToUse != ComplexPath) 136 drawEmphasisMarksForSimpleText(context, runInfo, mark, point); 137 else 138 drawEmphasisMarksForComplexText(context, runInfo, mark, point); 139 } 140 141 static inline void updateGlyphOverflowFromBounds(const IntRectExtent& glyphBounds, 142 const FontMetrics& fontMetrics, GlyphOverflow* glyphOverflow) 143 { 144 glyphOverflow->top = std::max<int>(glyphOverflow->top, 145 glyphBounds.top() - (glyphOverflow->computeBounds ? 0 : fontMetrics.ascent())); 146 glyphOverflow->bottom = std::max<int>(glyphOverflow->bottom, 147 glyphBounds.bottom() - (glyphOverflow->computeBounds ? 0 : fontMetrics.descent())); 148 glyphOverflow->left = glyphBounds.left(); 149 glyphOverflow->right = glyphBounds.right(); 150 } 151 152 float Font::width(const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* glyphOverflow) const 153 { 154 CodePath codePathToUse = codePath(run); 155 if (codePathToUse != ComplexPath) { 156 // The simple path can optimize the case where glyph overflow is not observable. 157 if (codePathToUse != SimpleWithGlyphOverflowPath && (glyphOverflow && !glyphOverflow->computeBounds)) 158 glyphOverflow = 0; 159 } 160 161 bool hasWordSpacingOrLetterSpacing = fontDescription().wordSpacing() || fontDescription().letterSpacing(); 162 bool isCacheable = codePathToUse == ComplexPath 163 && !hasWordSpacingOrLetterSpacing // Word spacing and letter spacing can change the width of a word. 164 && !run.allowTabs(); // If we allow tabs and a tab occurs inside a word, the width of the word varies based on its position on the line. 165 166 WidthCacheEntry* cacheEntry = isCacheable 167 ? m_fontFallbackList->widthCache().add(run, WidthCacheEntry()) 168 : 0; 169 if (cacheEntry && cacheEntry->isValid()) { 170 if (glyphOverflow) 171 updateGlyphOverflowFromBounds(cacheEntry->glyphBounds, fontMetrics(), glyphOverflow); 172 return cacheEntry->width; 173 } 174 175 float result; 176 IntRectExtent glyphBounds; 177 if (codePathToUse == ComplexPath) { 178 result = floatWidthForComplexText(run, fallbackFonts, &glyphBounds); 179 } else { 180 ASSERT(!isCacheable); 181 result = floatWidthForSimpleText(run, fallbackFonts, glyphOverflow ? &glyphBounds : 0); 182 } 183 184 if (cacheEntry && (!fallbackFonts || fallbackFonts->isEmpty())) { 185 cacheEntry->glyphBounds = glyphBounds; 186 cacheEntry->width = result; 187 } 188 189 if (glyphOverflow) 190 updateGlyphOverflowFromBounds(glyphBounds, fontMetrics(), glyphOverflow); 191 return result; 192 } 193 194 float Font::width(const TextRun& run, int& charsConsumed, Glyph& glyphId) const 195 { 196 #if ENABLE(SVG_FONTS) 197 if (TextRun::RenderingContext* renderingContext = run.renderingContext()) 198 return renderingContext->floatWidthUsingSVGFont(*this, run, charsConsumed, glyphId); 199 #endif 200 201 charsConsumed = run.length(); 202 glyphId = 0; 203 return width(run); 204 } 205 206 PassTextBlobPtr Font::buildTextBlob(const TextRunPaintInfo& runInfo, const FloatPoint& textOrigin, bool couldUseLCDRenderedText, CustomFontNotReadyAction customFontNotReadyAction) const 207 { 208 ASSERT(RuntimeEnabledFeatures::textBlobEnabled()); 209 210 // FIXME: Some logic in common with Font::drawText. Would be nice to 211 // deduplicate. 212 if (shouldSkipDrawing() && customFontNotReadyAction == DoNotPaintIfFontNotReady) 213 return nullptr; 214 215 CodePath codePathToUse = codePath(runInfo.run); 216 // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050 217 if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length())) 218 codePathToUse = ComplexPath; 219 220 if (codePathToUse != ComplexPath) 221 return buildTextBlobForSimpleText(runInfo, textOrigin, couldUseLCDRenderedText); 222 223 return nullptr; 224 } 225 226 PassTextBlobPtr Font::buildTextBlobForSimpleText(const TextRunPaintInfo& runInfo, const FloatPoint& textOrigin, bool couldUseLCDRenderedText) const 227 { 228 GlyphBuffer glyphBuffer; 229 float initialAdvance = getGlyphsAndAdvancesForSimpleText(runInfo, glyphBuffer); 230 ASSERT(!glyphBuffer.hasVerticalAdvances()); 231 232 if (glyphBuffer.isEmpty()) 233 return nullptr; 234 235 FloatRect blobBounds = runInfo.bounds; 236 blobBounds.moveBy(-textOrigin); 237 238 float ignoredWidth; 239 return buildTextBlob(glyphBuffer, initialAdvance, blobBounds, ignoredWidth, couldUseLCDRenderedText); 240 } 241 242 FloatRect Font::selectionRectForText(const TextRun& run, const FloatPoint& point, int h, int from, int to, bool accountForGlyphBounds) const 243 { 244 to = (to == -1 ? run.length() : to); 245 246 CodePath codePathToUse = codePath(run); 247 // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050 248 if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (from || to != run.length())) 249 codePathToUse = ComplexPath; 250 251 if (codePathToUse != ComplexPath) 252 return selectionRectForSimpleText(run, point, h, from, to, accountForGlyphBounds); 253 254 return selectionRectForComplexText(run, point, h, from, to); 255 } 256 257 int Font::offsetForPosition(const TextRun& run, float x, bool includePartialGlyphs) const 258 { 259 // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050 260 if (codePath(run) != ComplexPath && !fontDescription().typesettingFeatures()) 261 return offsetForPositionForSimpleText(run, x, includePartialGlyphs); 262 263 return offsetForPositionForComplexText(run, x, includePartialGlyphs); 264 } 265 266 void Font::setCodePath(CodePath p) 267 { 268 s_codePath = p; 269 } 270 271 CodePath Font::codePath() 272 { 273 return s_codePath; 274 } 275 276 CodePath Font::codePath(const TextRun& run) const 277 { 278 if (s_codePath != AutoPath) 279 return s_codePath; 280 281 #if ENABLE(SVG_FONTS) 282 if (run.renderingContext()) 283 return SimplePath; 284 #endif 285 286 if (m_fontDescription.featureSettings() && m_fontDescription.featureSettings()->size() > 0 && m_fontDescription.letterSpacing() == 0) 287 return ComplexPath; 288 289 if (m_fontDescription.widthVariant() != RegularWidth) 290 return ComplexPath; 291 292 if (run.length() > 1 && fontDescription().typesettingFeatures()) 293 return ComplexPath; 294 295 if (run.useComplexCodePath()) 296 return ComplexPath; 297 298 // FIXME: This really shouldn't be needed but for some reason the 299 // TextRendering setting doesn't propagate to typesettingFeatures in time 300 // for the prefs width calculation. 301 if (fontDescription().textRendering() == OptimizeLegibility || fontDescription().textRendering() == GeometricPrecision) 302 return ComplexPath; 303 304 if (!run.characterScanForCodePath()) 305 return SimplePath; 306 307 if (run.is8Bit()) 308 return SimplePath; 309 310 // Start from 0 since drawing and highlighting also measure the characters before run->from. 311 return Character::characterRangeCodePath(run.characters16(), run.length()); 312 } 313 314 void Font::willUseFontData(UChar32 character) const 315 { 316 const FontFamily& family = fontDescription().family(); 317 if (m_fontFallbackList && m_fontFallbackList->fontSelector() && !family.familyIsEmpty()) 318 m_fontFallbackList->fontSelector()->willUseFontData(fontDescription(), family.family(), character); 319 } 320 321 static inline bool isInRange(UChar32 character, UChar32 lowerBound, UChar32 upperBound) 322 { 323 return character >= lowerBound && character <= upperBound; 324 } 325 326 static bool shouldIgnoreRotation(UChar32 character) 327 { 328 if (character == 0x000A7 || character == 0x000A9 || character == 0x000AE) 329 return true; 330 331 if (character == 0x000B6 || character == 0x000BC || character == 0x000BD || character == 0x000BE) 332 return true; 333 334 if (isInRange(character, 0x002E5, 0x002EB)) 335 return true; 336 337 if (isInRange(character, 0x01100, 0x011FF) || isInRange(character, 0x01401, 0x0167F) || isInRange(character, 0x01800, 0x018FF)) 338 return true; 339 340 if (character == 0x02016 || character == 0x02018 || character == 0x02019 || character == 0x02020 || character == 0x02021 341 || character == 0x2030 || character == 0x02031) 342 return true; 343 344 if (isInRange(character, 0x0203B, 0x0203D) || character == 0x02042 || character == 0x02044 || character == 0x02047 345 || character == 0x02048 || character == 0x02049 || character == 0x2051) 346 return true; 347 348 if (isInRange(character, 0x02065, 0x02069) || isInRange(character, 0x020DD, 0x020E0) 349 || isInRange(character, 0x020E2, 0x020E4) || isInRange(character, 0x02100, 0x02117) 350 || isInRange(character, 0x02119, 0x02131) || isInRange(character, 0x02133, 0x0213F)) 351 return true; 352 353 if (isInRange(character, 0x02145, 0x0214A) || character == 0x0214C || character == 0x0214D 354 || isInRange(character, 0x0214F, 0x0218F)) 355 return true; 356 357 if (isInRange(character, 0x02300, 0x02307) || isInRange(character, 0x0230C, 0x0231F) 358 || isInRange(character, 0x02322, 0x0232B) || isInRange(character, 0x0237D, 0x0239A) 359 || isInRange(character, 0x023B4, 0x023B6) || isInRange(character, 0x023BA, 0x023CF) 360 || isInRange(character, 0x023D1, 0x023DB) || isInRange(character, 0x023E2, 0x024FF)) 361 return true; 362 363 if (isInRange(character, 0x025A0, 0x02619) || isInRange(character, 0x02620, 0x02767) 364 || isInRange(character, 0x02776, 0x02793) || isInRange(character, 0x02B12, 0x02B2F) 365 || isInRange(character, 0x02B4D, 0x02BFF) || isInRange(character, 0x02E80, 0x03007)) 366 return true; 367 368 if (character == 0x03012 || character == 0x03013 || isInRange(character, 0x03020, 0x0302F) 369 || isInRange(character, 0x03031, 0x0309F) || isInRange(character, 0x030A1, 0x030FB) 370 || isInRange(character, 0x030FD, 0x0A4CF)) 371 return true; 372 373 if (isInRange(character, 0x0A840, 0x0A87F) || isInRange(character, 0x0A960, 0x0A97F) 374 || isInRange(character, 0x0AC00, 0x0D7FF) || isInRange(character, 0x0E000, 0x0FAFF)) 375 return true; 376 377 if (isInRange(character, 0x0FE10, 0x0FE1F) || isInRange(character, 0x0FE30, 0x0FE48) 378 || isInRange(character, 0x0FE50, 0x0FE57) || isInRange(character, 0x0FE5F, 0x0FE62) 379 || isInRange(character, 0x0FE67, 0x0FE6F)) 380 return true; 381 382 if (isInRange(character, 0x0FF01, 0x0FF07) || isInRange(character, 0x0FF0A, 0x0FF0C) 383 || isInRange(character, 0x0FF0E, 0x0FF19) || isInRange(character, 0x0FF1F, 0x0FF3A)) 384 return true; 385 386 if (character == 0x0FF3C || character == 0x0FF3E) 387 return true; 388 389 if (isInRange(character, 0x0FF40, 0x0FF5A) || isInRange(character, 0x0FFE0, 0x0FFE2) 390 || isInRange(character, 0x0FFE4, 0x0FFE7) || isInRange(character, 0x0FFF0, 0x0FFF8) 391 || character == 0x0FFFD) 392 return true; 393 394 if (isInRange(character, 0x13000, 0x1342F) || isInRange(character, 0x1B000, 0x1B0FF) 395 || isInRange(character, 0x1D000, 0x1D1FF) || isInRange(character, 0x1D300, 0x1D37F) 396 || isInRange(character, 0x1F000, 0x1F64F) || isInRange(character, 0x1F680, 0x1F77F)) 397 return true; 398 399 if (isInRange(character, 0x20000, 0x2FFFD) || isInRange(character, 0x30000, 0x3FFFD)) 400 return true; 401 402 return false; 403 } 404 405 static inline std::pair<GlyphData, GlyphPage*> glyphDataAndPageForNonCJKCharacterWithGlyphOrientation(UChar32 character, NonCJKGlyphOrientation orientation, GlyphData& data, GlyphPage* page, unsigned pageNumber) 406 { 407 if (orientation == NonCJKGlyphOrientationUpright || shouldIgnoreRotation(character)) { 408 RefPtr<SimpleFontData> uprightFontData = data.fontData->uprightOrientationFontData(); 409 GlyphPageTreeNode* uprightNode = GlyphPageTreeNode::getRootChild(uprightFontData.get(), pageNumber); 410 GlyphPage* uprightPage = uprightNode->page(); 411 if (uprightPage) { 412 GlyphData uprightData = uprightPage->glyphDataForCharacter(character); 413 // If the glyphs are the same, then we know we can just use the horizontal glyph rotated vertically to be upright. 414 if (data.glyph == uprightData.glyph) 415 return std::make_pair(data, page); 416 // The glyphs are distinct, meaning that the font has a vertical-right glyph baked into it. We can't use that 417 // glyph, so we fall back to the upright data and use the horizontal glyph. 418 if (uprightData.fontData) 419 return std::make_pair(uprightData, uprightPage); 420 } 421 } else if (orientation == NonCJKGlyphOrientationVerticalRight) { 422 RefPtr<SimpleFontData> verticalRightFontData = data.fontData->verticalRightOrientationFontData(); 423 GlyphPageTreeNode* verticalRightNode = GlyphPageTreeNode::getRootChild(verticalRightFontData.get(), pageNumber); 424 GlyphPage* verticalRightPage = verticalRightNode->page(); 425 if (verticalRightPage) { 426 GlyphData verticalRightData = verticalRightPage->glyphDataForCharacter(character); 427 // If the glyphs are distinct, we will make the assumption that the font has a vertical-right glyph baked 428 // into it. 429 if (data.glyph != verticalRightData.glyph) 430 return std::make_pair(data, page); 431 // The glyphs are identical, meaning that we should just use the horizontal glyph. 432 if (verticalRightData.fontData) 433 return std::make_pair(verticalRightData, verticalRightPage); 434 } 435 } 436 return std::make_pair(data, page); 437 } 438 439 std::pair<GlyphData, GlyphPage*> Font::glyphDataAndPageForCharacter(UChar32& c, bool mirror, bool normalizeSpace, FontDataVariant variant) const 440 { 441 ASSERT(isMainThread()); 442 443 if (variant == AutoVariant) { 444 if (m_fontDescription.variant() == FontVariantSmallCaps && !primaryFont()->isSVGFont()) { 445 UChar32 upperC = toUpper(c); 446 if (upperC != c) { 447 c = upperC; 448 variant = SmallCapsVariant; 449 } else { 450 variant = NormalVariant; 451 } 452 } else { 453 variant = NormalVariant; 454 } 455 } 456 457 if (normalizeSpace && Character::isNormalizedCanvasSpaceCharacter(c)) 458 c = space; 459 460 if (mirror) 461 c = mirroredChar(c); 462 463 unsigned pageNumber = (c / GlyphPage::size); 464 465 GlyphPageTreeNode* node = m_fontFallbackList->getPageNode(pageNumber); 466 if (!node) { 467 node = GlyphPageTreeNode::getRootChild(fontDataAt(0), pageNumber); 468 m_fontFallbackList->setPageNode(pageNumber, node); 469 } 470 471 GlyphPage* page = 0; 472 if (variant == NormalVariant) { 473 // Fastest loop, for the common case (normal variant). 474 while (true) { 475 page = node->page(); 476 if (page) { 477 GlyphData data = page->glyphDataForCharacter(c); 478 if (data.fontData && (data.fontData->platformData().orientation() == Horizontal || data.fontData->isTextOrientationFallback())) 479 return std::make_pair(data, page); 480 481 if (data.fontData) { 482 if (Character::isCJKIdeographOrSymbol(c)) { 483 if (!data.fontData->hasVerticalGlyphs()) { 484 // Use the broken ideograph font data. The broken ideograph font will use the horizontal width of glyphs 485 // to make sure you get a square (even for broken glyphs like symbols used for punctuation). 486 variant = BrokenIdeographVariant; 487 break; 488 } 489 } else { 490 return glyphDataAndPageForNonCJKCharacterWithGlyphOrientation(c, m_fontDescription.nonCJKGlyphOrientation(), data, page, pageNumber); 491 } 492 493 return std::make_pair(data, page); 494 } 495 496 if (node->isSystemFallback()) 497 break; 498 } 499 500 // Proceed with the fallback list. 501 node = node->getChild(fontDataAt(node->level()), pageNumber); 502 m_fontFallbackList->setPageNode(pageNumber, node); 503 } 504 } 505 if (variant != NormalVariant) { 506 while (true) { 507 page = node->page(); 508 if (page) { 509 GlyphData data = page->glyphDataForCharacter(c); 510 if (data.fontData) { 511 // The variantFontData function should not normally return 0. 512 // But if it does, we will just render the capital letter big. 513 RefPtr<SimpleFontData> variantFontData = data.fontData->variantFontData(m_fontDescription, variant); 514 if (!variantFontData) 515 return std::make_pair(data, page); 516 517 GlyphPageTreeNode* variantNode = GlyphPageTreeNode::getRootChild(variantFontData.get(), pageNumber); 518 GlyphPage* variantPage = variantNode->page(); 519 if (variantPage) { 520 GlyphData data = variantPage->glyphDataForCharacter(c); 521 if (data.fontData) 522 return std::make_pair(data, variantPage); 523 } 524 525 // Do not attempt system fallback off the variantFontData. This is the very unlikely case that 526 // a font has the lowercase character but the small caps font does not have its uppercase version. 527 return std::make_pair(variantFontData->missingGlyphData(), page); 528 } 529 530 if (node->isSystemFallback()) 531 break; 532 } 533 534 // Proceed with the fallback list. 535 node = node->getChild(fontDataAt(node->level()), pageNumber); 536 m_fontFallbackList->setPageNode(pageNumber, node); 537 } 538 } 539 540 ASSERT(page); 541 ASSERT(node->isSystemFallback()); 542 543 // System fallback is character-dependent. When we get here, we 544 // know that the character in question isn't in the system fallback 545 // font's glyph page. Try to lazily create it here. 546 547 // FIXME: Unclear if this should normalizeSpaces above 0xFFFF. 548 // Doing so changes fast/text/international/plane2-diffs.html 549 UChar32 characterToRender = c; 550 if (characterToRender <= 0xFFFF) 551 characterToRender = Character::normalizeSpaces(characterToRender); 552 const SimpleFontData* fontDataToSubstitute = fontDataAt(0)->fontDataForCharacter(characterToRender); 553 RefPtr<SimpleFontData> characterFontData = FontCache::fontCache()->fallbackFontForCharacter(m_fontDescription, characterToRender, fontDataToSubstitute); 554 if (characterFontData) { 555 if (characterFontData->platformData().orientation() == Vertical && !characterFontData->hasVerticalGlyphs() && Character::isCJKIdeographOrSymbol(c)) 556 variant = BrokenIdeographVariant; 557 if (variant != NormalVariant) 558 characterFontData = characterFontData->variantFontData(m_fontDescription, variant); 559 } 560 if (characterFontData) { 561 // Got the fallback glyph and font. 562 GlyphPage* fallbackPage = GlyphPageTreeNode::getRootChild(characterFontData.get(), pageNumber)->page(); 563 GlyphData data = fallbackPage && fallbackPage->glyphForCharacter(c) ? fallbackPage->glyphDataForCharacter(c) : characterFontData->missingGlyphData(); 564 // Cache it so we don't have to do system fallback again next time. 565 if (variant == NormalVariant) { 566 page->setGlyphDataForCharacter(c, data.glyph, data.fontData); 567 data.fontData->setMaxGlyphPageTreeLevel(std::max(data.fontData->maxGlyphPageTreeLevel(), node->level())); 568 if (!Character::isCJKIdeographOrSymbol(c) && data.fontData->platformData().orientation() != Horizontal && !data.fontData->isTextOrientationFallback()) 569 return glyphDataAndPageForNonCJKCharacterWithGlyphOrientation(c, m_fontDescription.nonCJKGlyphOrientation(), data, page, pageNumber); 570 } 571 return std::make_pair(data, page); 572 } 573 574 // Even system fallback can fail; use the missing glyph in that case. 575 // FIXME: It would be nicer to use the missing glyph from the last resort font instead. 576 GlyphData data = primaryFont()->missingGlyphData(); 577 if (variant == NormalVariant) { 578 page->setGlyphDataForCharacter(c, data.glyph, data.fontData); 579 data.fontData->setMaxGlyphPageTreeLevel(std::max(data.fontData->maxGlyphPageTreeLevel(), node->level())); 580 } 581 return std::make_pair(data, page); 582 } 583 584 bool Font::primaryFontHasGlyphForCharacter(UChar32 character) const 585 { 586 unsigned pageNumber = (character / GlyphPage::size); 587 588 GlyphPageTreeNode* node = GlyphPageTreeNode::getRootChild(primaryFont(), pageNumber); 589 GlyphPage* page = node->page(); 590 591 return page && page->glyphForCharacter(character); 592 } 593 594 // FIXME: This function may not work if the emphasis mark uses a complex script, but none of the 595 // standard emphasis marks do so. 596 bool Font::getEmphasisMarkGlyphData(const AtomicString& mark, GlyphData& glyphData) const 597 { 598 if (mark.isEmpty()) 599 return false; 600 601 UChar32 character = mark[0]; 602 603 if (U16_IS_SURROGATE(character)) { 604 if (!U16_IS_SURROGATE_LEAD(character)) 605 return false; 606 607 if (mark.length() < 2) 608 return false; 609 610 UChar low = mark[1]; 611 if (!U16_IS_TRAIL(low)) 612 return false; 613 614 character = U16_GET_SUPPLEMENTARY(character, low); 615 } 616 617 bool normalizeSpace = false; 618 glyphData = glyphDataForCharacter(character, false, normalizeSpace, EmphasisMarkVariant); 619 return true; 620 } 621 622 int Font::emphasisMarkAscent(const AtomicString& mark) const 623 { 624 FontCachePurgePreventer purgePreventer; 625 626 GlyphData markGlyphData; 627 if (!getEmphasisMarkGlyphData(mark, markGlyphData)) 628 return 0; 629 630 const SimpleFontData* markFontData = markGlyphData.fontData; 631 ASSERT(markFontData); 632 if (!markFontData) 633 return 0; 634 635 return markFontData->fontMetrics().ascent(); 636 } 637 638 int Font::emphasisMarkDescent(const AtomicString& mark) const 639 { 640 FontCachePurgePreventer purgePreventer; 641 642 GlyphData markGlyphData; 643 if (!getEmphasisMarkGlyphData(mark, markGlyphData)) 644 return 0; 645 646 const SimpleFontData* markFontData = markGlyphData.fontData; 647 ASSERT(markFontData); 648 if (!markFontData) 649 return 0; 650 651 return markFontData->fontMetrics().descent(); 652 } 653 654 int Font::emphasisMarkHeight(const AtomicString& mark) const 655 { 656 FontCachePurgePreventer purgePreventer; 657 658 GlyphData markGlyphData; 659 if (!getEmphasisMarkGlyphData(mark, markGlyphData)) 660 return 0; 661 662 const SimpleFontData* markFontData = markGlyphData.fontData; 663 ASSERT(markFontData); 664 if (!markFontData) 665 return 0; 666 667 return markFontData->fontMetrics().height(); 668 } 669 670 float Font::getGlyphsAndAdvancesForSimpleText(const TextRunPaintInfo& runInfo, GlyphBuffer& glyphBuffer, ForTextEmphasisOrNot forTextEmphasis) const 671 { 672 float initialAdvance; 673 674 WidthIterator it(this, runInfo.run, 0, false, forTextEmphasis); 675 it.advance(runInfo.from); 676 float beforeWidth = it.m_runWidthSoFar; 677 it.advance(runInfo.to, &glyphBuffer); 678 679 if (glyphBuffer.isEmpty()) 680 return 0; 681 682 float afterWidth = it.m_runWidthSoFar; 683 684 if (runInfo.run.rtl()) { 685 it.advance(runInfo.run.length()); 686 initialAdvance = it.m_runWidthSoFar - afterWidth; 687 glyphBuffer.reverse(); 688 } else { 689 initialAdvance = beforeWidth; 690 } 691 692 return initialAdvance; 693 } 694 695 float Font::drawSimpleText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const FloatPoint& point) const 696 { 697 // This glyph buffer holds our glyphs+advances+font data for each glyph. 698 GlyphBuffer glyphBuffer; 699 float initialAdvance = getGlyphsAndAdvancesForSimpleText(runInfo, glyphBuffer); 700 ASSERT(!glyphBuffer.hasVerticalAdvances()); 701 702 if (glyphBuffer.isEmpty()) 703 return 0; 704 705 TextBlobPtr textBlob; 706 float advance = 0; 707 if (RuntimeEnabledFeatures::textBlobEnabled()) { 708 // Using text blob causes a small difference in how gradients and 709 // patterns are rendered. 710 // FIXME: Fix this, most likely in Skia. 711 if (!context->strokeGradient() && !context->strokePattern() && !context->fillGradient() && !context->fillPattern()) { 712 FloatRect blobBounds = runInfo.bounds; 713 blobBounds.moveBy(-point); 714 textBlob = buildTextBlob(glyphBuffer, initialAdvance, blobBounds, advance, context->couldUseLCDRenderedText()); 715 } 716 } 717 718 if (textBlob) { 719 drawTextBlob(context, textBlob.get(), point.data()); 720 return advance; 721 } 722 723 FloatPoint startPoint(point.x() + initialAdvance, point.y()); 724 return drawGlyphBuffer(context, runInfo, glyphBuffer, startPoint); 725 } 726 727 void Font::drawEmphasisMarksForSimpleText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const AtomicString& mark, const FloatPoint& point) const 728 { 729 GlyphBuffer glyphBuffer; 730 float initialAdvance = getGlyphsAndAdvancesForSimpleText(runInfo, glyphBuffer, ForTextEmphasis); 731 732 if (glyphBuffer.isEmpty()) 733 return; 734 735 drawEmphasisMarks(context, runInfo, glyphBuffer, mark, FloatPoint(point.x() + initialAdvance, point.y())); 736 } 737 738 float Font::drawGlyphBuffer(GraphicsContext* context, const TextRunPaintInfo& runInfo, const GlyphBuffer& glyphBuffer, const FloatPoint& point) const 739 { 740 // Draw each contiguous run of glyphs that use the same font data. 741 const SimpleFontData* fontData = glyphBuffer.fontDataAt(0); 742 FloatPoint startPoint(point); 743 FloatPoint nextPoint = startPoint + glyphBuffer.advanceAt(0); 744 unsigned lastFrom = 0; 745 unsigned nextGlyph = 1; 746 #if ENABLE(SVG_FONTS) 747 TextRun::RenderingContext* renderingContext = runInfo.run.renderingContext(); 748 #endif 749 750 float widthSoFar = 0; 751 widthSoFar += glyphBuffer.advanceAt(0).width(); 752 while (nextGlyph < glyphBuffer.size()) { 753 const SimpleFontData* nextFontData = glyphBuffer.fontDataAt(nextGlyph); 754 755 if (nextFontData != fontData) { 756 #if ENABLE(SVG_FONTS) 757 if (renderingContext && fontData->isSVGFont()) 758 renderingContext->drawSVGGlyphs(context, runInfo.run, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint); 759 else 760 #endif 761 drawGlyphs(context, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint, runInfo.bounds); 762 763 lastFrom = nextGlyph; 764 fontData = nextFontData; 765 startPoint = nextPoint; 766 } 767 nextPoint += glyphBuffer.advanceAt(nextGlyph); 768 widthSoFar += glyphBuffer.advanceAt(nextGlyph).width(); 769 nextGlyph++; 770 } 771 772 #if ENABLE(SVG_FONTS) 773 if (renderingContext && fontData->isSVGFont()) 774 renderingContext->drawSVGGlyphs(context, runInfo.run, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint); 775 else 776 #endif 777 drawGlyphs(context, fontData, glyphBuffer, lastFrom, nextGlyph - lastFrom, startPoint, runInfo.bounds); 778 return widthSoFar; 779 } 780 781 inline static float offsetToMiddleOfGlyph(const SimpleFontData* fontData, Glyph glyph) 782 { 783 if (fontData->platformData().orientation() == Horizontal) { 784 FloatRect bounds = fontData->boundsForGlyph(glyph); 785 return bounds.x() + bounds.width() / 2; 786 } 787 // FIXME: Use glyph bounds once they make sense for vertical fonts. 788 return fontData->widthForGlyph(glyph) / 2; 789 } 790 791 inline static float offsetToMiddleOfAdvanceAtIndex(const GlyphBuffer& glyphBuffer, size_t i) 792 { 793 return glyphBuffer.advanceAt(i).width() / 2; 794 } 795 796 void Font::drawEmphasisMarks(GraphicsContext* context, const TextRunPaintInfo& runInfo, const GlyphBuffer& glyphBuffer, const AtomicString& mark, const FloatPoint& point) const 797 { 798 FontCachePurgePreventer purgePreventer; 799 800 GlyphData markGlyphData; 801 if (!getEmphasisMarkGlyphData(mark, markGlyphData)) 802 return; 803 804 const SimpleFontData* markFontData = markGlyphData.fontData; 805 ASSERT(markFontData); 806 if (!markFontData) 807 return; 808 809 Glyph markGlyph = markGlyphData.glyph; 810 Glyph spaceGlyph = markFontData->spaceGlyph(); 811 812 float middleOfLastGlyph = offsetToMiddleOfAdvanceAtIndex(glyphBuffer, 0); 813 FloatPoint startPoint(point.x() + middleOfLastGlyph - offsetToMiddleOfGlyph(markFontData, markGlyph), point.y()); 814 815 GlyphBuffer markBuffer; 816 for (unsigned i = 0; i + 1 < glyphBuffer.size(); ++i) { 817 float middleOfNextGlyph = offsetToMiddleOfAdvanceAtIndex(glyphBuffer, i + 1); 818 float advance = glyphBuffer.advanceAt(i).width() - middleOfLastGlyph + middleOfNextGlyph; 819 markBuffer.add(glyphBuffer.glyphAt(i) ? markGlyph : spaceGlyph, markFontData, advance); 820 middleOfLastGlyph = middleOfNextGlyph; 821 } 822 markBuffer.add(glyphBuffer.glyphAt(glyphBuffer.size() - 1) ? markGlyph : spaceGlyph, markFontData, 0); 823 824 drawGlyphBuffer(context, runInfo, markBuffer, startPoint); 825 } 826 827 float Font::floatWidthForSimpleText(const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts, IntRectExtent* glyphBounds) const 828 { 829 WidthIterator it(this, run, fallbackFonts, glyphBounds); 830 it.advance(run.length()); 831 832 if (glyphBounds) { 833 glyphBounds->setTop(floorf(-it.minGlyphBoundingBoxY())); 834 glyphBounds->setBottom(ceilf(it.maxGlyphBoundingBoxY())); 835 glyphBounds->setLeft(floorf(it.firstGlyphOverflow())); 836 glyphBounds->setRight(ceilf(it.lastGlyphOverflow())); 837 } 838 839 return it.m_runWidthSoFar; 840 } 841 842 FloatRect Font::pixelSnappedSelectionRect(float fromX, float toX, float y, float height) 843 { 844 // Using roundf() rather than ceilf() for the right edge as a compromise to 845 // ensure correct caret positioning. 846 float roundedX = roundf(fromX); 847 return FloatRect(roundedX, y, roundf(toX - roundedX), height); 848 } 849 850 FloatRect Font::selectionRectForSimpleText(const TextRun& run, const FloatPoint& point, int h, int from, int to, bool accountForGlyphBounds) const 851 { 852 WidthIterator it(this, run, 0, accountForGlyphBounds); 853 it.advance(from); 854 float fromX = it.m_runWidthSoFar; 855 it.advance(to); 856 float toX = it.m_runWidthSoFar; 857 858 if (run.rtl()) { 859 it.advance(run.length()); 860 float totalWidth = it.m_runWidthSoFar; 861 float beforeWidth = fromX; 862 float afterWidth = toX; 863 fromX = totalWidth - afterWidth; 864 toX = totalWidth - beforeWidth; 865 } 866 867 return pixelSnappedSelectionRect(point.x() + fromX, point.x() + toX, 868 accountForGlyphBounds ? it.minGlyphBoundingBoxY() : point.y(), 869 accountForGlyphBounds ? it.maxGlyphBoundingBoxY() - it.minGlyphBoundingBoxY() : h); 870 } 871 872 int Font::offsetForPositionForSimpleText(const TextRun& run, float x, bool includePartialGlyphs) const 873 { 874 float delta = x; 875 876 WidthIterator it(this, run); 877 unsigned offset; 878 if (run.rtl()) { 879 delta -= floatWidthForSimpleText(run); 880 while (1) { 881 offset = it.m_currentCharacter; 882 float w; 883 if (!it.advanceOneCharacter(w)) 884 break; 885 delta += w; 886 if (includePartialGlyphs) { 887 if (delta - w / 2 >= 0) 888 break; 889 } else { 890 if (delta >= 0) 891 break; 892 } 893 } 894 } else { 895 while (1) { 896 offset = it.m_currentCharacter; 897 float w; 898 if (!it.advanceOneCharacter(w)) 899 break; 900 delta -= w; 901 if (includePartialGlyphs) { 902 if (delta + w / 2 <= 0) 903 break; 904 } else { 905 if (delta <= 0) 906 break; 907 } 908 } 909 } 910 911 return offset; 912 } 913 914 } // namespace blink 915