1/* 2 * Copyright (C) Research In Motion Limited 2010-2012. All rights reserved. 3 * 4 * This library is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Library General Public 6 * License as published by the Free Software Foundation; either 7 * version 2 of the License, or (at your option) any later version. 8 * 9 * This library is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * Library General Public License for more details. 13 * 14 * You should have received a copy of the GNU Library General Public License 15 * along with this library; see the file COPYING.LIB. If not, write to 16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 17 * Boston, MA 02110-1301, USA. 18 */ 19 20#include "config.h" 21 22#include "core/rendering/svg/SVGTextLayoutEngine.h" 23 24#include "core/rendering/svg/RenderSVGInlineText.h" 25#include "core/rendering/svg/RenderSVGTextPath.h" 26#include "core/rendering/svg/SVGInlineTextBox.h" 27#include "core/rendering/svg/SVGTextLayoutEngineBaseline.h" 28#include "core/rendering/svg/SVGTextLayoutEngineSpacing.h" 29#include "core/svg/SVGElement.h" 30#include "core/svg/SVGLengthContext.h" 31 32// Set to a value > 0 to dump the text fragments 33#define DUMP_TEXT_FRAGMENTS 0 34 35namespace blink { 36 37SVGTextLayoutEngine::SVGTextLayoutEngine(Vector<SVGTextLayoutAttributes*>& layoutAttributes) 38 : m_layoutAttributes(layoutAttributes) 39 , m_layoutAttributesPosition(0) 40 , m_logicalCharacterOffset(0) 41 , m_logicalMetricsListOffset(0) 42 , m_visualCharacterOffset(0) 43 , m_visualMetricsListOffset(0) 44 , m_x(0) 45 , m_y(0) 46 , m_dx(0) 47 , m_dy(0) 48 , m_isVerticalText(false) 49 , m_inPathLayout(false) 50 , m_textPathCalculator(0) 51 , m_textPathLength(0) 52 , m_textPathCurrentOffset(0) 53 , m_textPathSpacing(0) 54 , m_textPathScaling(1) 55{ 56 ASSERT(!m_layoutAttributes.isEmpty()); 57} 58 59void SVGTextLayoutEngine::updateCharacterPositionIfNeeded(float& x, float& y) 60{ 61 if (m_inPathLayout) 62 return; 63 64 // Replace characters x/y position, with the current text position plus any 65 // relative adjustments, if it doesn't specify an absolute position itself. 66 if (x == SVGTextLayoutAttributes::emptyValue()) 67 x = m_x + m_dx; 68 69 if (y == SVGTextLayoutAttributes::emptyValue()) 70 y = m_y + m_dy; 71 72 m_dx = 0; 73 m_dy = 0; 74} 75 76void SVGTextLayoutEngine::updateCurrentTextPosition(float x, float y, float glyphAdvance) 77{ 78 // Update current text position after processing the character. 79 if (m_isVerticalText) { 80 m_x = x; 81 m_y = y + glyphAdvance; 82 } else { 83 m_x = x + glyphAdvance; 84 m_y = y; 85 } 86} 87 88void SVGTextLayoutEngine::updateRelativePositionAdjustmentsIfNeeded(float dx, float dy) 89{ 90 // Update relative positioning information. 91 if (dx == SVGTextLayoutAttributes::emptyValue() && dy == SVGTextLayoutAttributes::emptyValue()) 92 return; 93 94 if (dx == SVGTextLayoutAttributes::emptyValue()) 95 dx = 0; 96 if (dy == SVGTextLayoutAttributes::emptyValue()) 97 dy = 0; 98 99 if (m_inPathLayout) { 100 if (m_isVerticalText) { 101 m_dx += dx; 102 m_dy = dy; 103 } else { 104 m_dx = dx; 105 m_dy += dy; 106 } 107 108 return; 109 } 110 111 m_dx = dx; 112 m_dy = dy; 113} 114 115void SVGTextLayoutEngine::recordTextFragment(SVGInlineTextBox* textBox, const Vector<SVGTextMetrics>& textMetricsValues) 116{ 117 ASSERT(!m_currentTextFragment.length); 118 ASSERT(m_visualMetricsListOffset > 0); 119 120 // Figure out length of fragment. 121 m_currentTextFragment.length = m_visualCharacterOffset - m_currentTextFragment.characterOffset; 122 123 // Figure out fragment metrics. 124 const SVGTextMetrics& lastCharacterMetrics = textMetricsValues.at(m_visualMetricsListOffset - 1); 125 m_currentTextFragment.width = lastCharacterMetrics.width(); 126 m_currentTextFragment.height = lastCharacterMetrics.height(); 127 128 if (m_currentTextFragment.length > 1) { 129 // SVGTextLayoutAttributesBuilder assures that the length of the range is equal to the sum of the individual lengths of the glyphs. 130 float length = 0; 131 if (m_isVerticalText) { 132 for (unsigned i = m_currentTextFragment.metricsListOffset; i < m_visualMetricsListOffset; ++i) 133 length += textMetricsValues.at(i).height(); 134 m_currentTextFragment.height = length; 135 } else { 136 for (unsigned i = m_currentTextFragment.metricsListOffset; i < m_visualMetricsListOffset; ++i) 137 length += textMetricsValues.at(i).width(); 138 m_currentTextFragment.width = length; 139 } 140 } 141 142 textBox->textFragments().append(m_currentTextFragment); 143 m_currentTextFragment = SVGTextFragment(); 144} 145 146bool SVGTextLayoutEngine::parentDefinesTextLength(RenderObject* parent) const 147{ 148 RenderObject* currentParent = parent; 149 while (currentParent) { 150 if (SVGTextContentElement* textContentElement = SVGTextContentElement::elementFromRenderer(currentParent)) { 151 SVGLengthContext lengthContext(textContentElement); 152 if (textContentElement->lengthAdjust()->currentValue()->enumValue() == SVGLengthAdjustSpacing && textContentElement->textLengthIsSpecifiedByUser()) 153 return true; 154 } 155 156 if (currentParent->isSVGText()) 157 return false; 158 159 currentParent = currentParent->parent(); 160 } 161 162 ASSERT_NOT_REACHED(); 163 return false; 164} 165 166void SVGTextLayoutEngine::beginTextPathLayout(RenderObject* object, SVGTextLayoutEngine& lineLayout) 167{ 168 ASSERT(object); 169 170 m_inPathLayout = true; 171 RenderSVGTextPath* textPath = toRenderSVGTextPath(object); 172 173 Path path = textPath->layoutPath(); 174 if (path.isEmpty()) 175 return; 176 m_textPathCalculator = new Path::PositionCalculator(path); 177 m_textPathStartOffset = textPath->startOffset(); 178 m_textPathLength = path.length(); 179 if (m_textPathStartOffset > 0 && m_textPathStartOffset <= 1) 180 m_textPathStartOffset *= m_textPathLength; 181 182 float totalLength = 0; 183 unsigned totalCharacters = 0; 184 185 lineLayout.m_chunkLayoutBuilder.buildTextChunks(lineLayout.m_lineLayoutBoxes); 186 const Vector<SVGTextChunk>& textChunks = lineLayout.m_chunkLayoutBuilder.textChunks(); 187 188 unsigned size = textChunks.size(); 189 for (unsigned i = 0; i < size; ++i) { 190 const SVGTextChunk& chunk = textChunks.at(i); 191 192 float length = 0; 193 unsigned characters = 0; 194 chunk.calculateLength(length, characters); 195 196 // Handle text-anchor as additional start offset for text paths. 197 m_textPathStartOffset += chunk.calculateTextAnchorShift(length); 198 199 totalLength += length; 200 totalCharacters += characters; 201 } 202 203 m_textPathCurrentOffset = m_textPathStartOffset; 204 205 // Eventually handle textLength adjustments. 206 SVGLengthAdjustType lengthAdjust = SVGLengthAdjustUnknown; 207 float desiredTextLength = 0; 208 209 if (SVGTextContentElement* textContentElement = SVGTextContentElement::elementFromRenderer(textPath)) { 210 SVGLengthContext lengthContext(textContentElement); 211 lengthAdjust = textContentElement->lengthAdjust()->currentValue()->enumValue(); 212 if (textContentElement->textLengthIsSpecifiedByUser()) 213 desiredTextLength = textContentElement->textLength()->currentValue()->value(lengthContext); 214 else 215 desiredTextLength = 0; 216 } 217 218 if (!desiredTextLength) 219 return; 220 221 if (lengthAdjust == SVGLengthAdjustSpacing) 222 m_textPathSpacing = (desiredTextLength - totalLength) / totalCharacters; 223 else 224 m_textPathScaling = desiredTextLength / totalLength; 225} 226 227void SVGTextLayoutEngine::endTextPathLayout() 228{ 229 m_inPathLayout = false; 230 delete m_textPathCalculator; 231 m_textPathCalculator = 0; 232 m_textPathLength = 0; 233 m_textPathStartOffset = 0; 234 m_textPathCurrentOffset = 0; 235 m_textPathSpacing = 0; 236 m_textPathScaling = 1; 237} 238 239void SVGTextLayoutEngine::layoutInlineTextBox(SVGInlineTextBox* textBox) 240{ 241 ASSERT(textBox); 242 243 RenderSVGInlineText& text = toRenderSVGInlineText(textBox->renderer()); 244 ASSERT(text.parent()); 245 ASSERT(text.parent()->node()); 246 ASSERT(text.parent()->node()->isSVGElement()); 247 248 const RenderStyle* style = text.style(); 249 ASSERT(style); 250 251 textBox->clearTextFragments(); 252 m_isVerticalText = style->svgStyle().isVerticalWritingMode(); 253 layoutTextOnLineOrPath(textBox, text, *style); 254 255 if (m_inPathLayout) { 256 m_pathLayoutBoxes.append(textBox); 257 return; 258 } 259 260 m_lineLayoutBoxes.append(textBox); 261} 262 263#if DUMP_TEXT_FRAGMENTS > 0 264static inline void dumpTextBoxes(Vector<SVGInlineTextBox*>& boxes) 265{ 266 unsigned boxCount = boxes.size(); 267 fprintf(stderr, "Dumping all text fragments in text sub tree, %i boxes\n", boxCount); 268 269 for (unsigned boxPosition = 0; boxPosition < boxCount; ++boxPosition) { 270 SVGInlineTextBox* textBox = boxes.at(boxPosition); 271 Vector<SVGTextFragment>& fragments = textBox->textFragments(); 272 fprintf(stderr, "-> Box %i: Dumping text fragments for SVGInlineTextBox, textBox=%p, textRenderer=%p\n", boxPosition, textBox, textBox->textRenderer()); 273 fprintf(stderr, " textBox properties, start=%i, len=%i, box direction=%i\n", textBox->start(), textBox->len(), textBox->direction()); 274 fprintf(stderr, " textRenderer properties, textLength=%i\n", textBox->textRenderer()->textLength()); 275 276 String characters = textBox->textRenderer()->text(); 277 278 unsigned fragmentCount = fragments.size(); 279 for (unsigned i = 0; i < fragmentCount; ++i) { 280 SVGTextFragment& fragment = fragments.at(i); 281 String fragmentString = characters.substring(fragment.characterOffset, fragment.length); 282 fprintf(stderr, " -> Fragment %i, x=%lf, y=%lf, width=%lf, height=%lf, characterOffset=%i, length=%i, characters='%s'\n" 283 , i, fragment.x, fragment.y, fragment.width, fragment.height, fragment.characterOffset, fragment.length, fragmentString.utf8().data()); 284 } 285 } 286} 287#endif 288 289void SVGTextLayoutEngine::finalizeTransformMatrices(Vector<SVGInlineTextBox*>& boxes) 290{ 291 unsigned boxCount = boxes.size(); 292 if (!boxCount) 293 return; 294 295 for (unsigned boxPosition = 0; boxPosition < boxCount; ++boxPosition) { 296 SVGInlineTextBox* textBox = boxes.at(boxPosition); 297 AffineTransform textBoxTransformation = m_chunkLayoutBuilder.transformationForTextBox(textBox); 298 if (textBoxTransformation.isIdentity()) 299 continue; 300 301 Vector<SVGTextFragment>& fragments = textBox->textFragments(); 302 unsigned fragmentCount = fragments.size(); 303 for (unsigned i = 0; i < fragmentCount; ++i) { 304 ASSERT(fragments[i].lengthAdjustTransform.isIdentity()); 305 fragments[i].lengthAdjustTransform = textBoxTransformation; 306 } 307 } 308 309 boxes.clear(); 310} 311 312void SVGTextLayoutEngine::finishLayout() 313{ 314 // After all text fragments are stored in their correpsonding SVGInlineTextBoxes, we can layout individual text chunks. 315 // Chunk layouting is only performed for line layout boxes, not for path layout, where it has already been done. 316 m_chunkLayoutBuilder.layoutTextChunks(m_lineLayoutBoxes); 317 318 // Finalize transform matrices, after the chunk layout corrections have been applied, and all fragment x/y positions are finalized. 319 if (!m_lineLayoutBoxes.isEmpty()) { 320#if DUMP_TEXT_FRAGMENTS > 0 321 fprintf(stderr, "Line layout: "); 322 dumpTextBoxes(m_lineLayoutBoxes); 323#endif 324 325 finalizeTransformMatrices(m_lineLayoutBoxes); 326 } 327 328 if (!m_pathLayoutBoxes.isEmpty()) { 329#if DUMP_TEXT_FRAGMENTS > 0 330 fprintf(stderr, "Path layout: "); 331 dumpTextBoxes(m_pathLayoutBoxes); 332#endif 333 334 finalizeTransformMatrices(m_pathLayoutBoxes); 335 } 336} 337 338bool SVGTextLayoutEngine::currentLogicalCharacterAttributes(SVGTextLayoutAttributes*& logicalAttributes) 339{ 340 if (m_layoutAttributesPosition == m_layoutAttributes.size()) 341 return false; 342 343 logicalAttributes = m_layoutAttributes[m_layoutAttributesPosition]; 344 ASSERT(logicalAttributes); 345 346 if (m_logicalCharacterOffset != logicalAttributes->context()->textLength()) 347 return true; 348 349 ++m_layoutAttributesPosition; 350 if (m_layoutAttributesPosition == m_layoutAttributes.size()) 351 return false; 352 353 logicalAttributes = m_layoutAttributes[m_layoutAttributesPosition]; 354 m_logicalMetricsListOffset = 0; 355 m_logicalCharacterOffset = 0; 356 return true; 357} 358 359bool SVGTextLayoutEngine::currentLogicalCharacterMetrics(SVGTextLayoutAttributes*& logicalAttributes, SVGTextMetrics& logicalMetrics) 360{ 361 const Vector<SVGTextMetrics>* textMetricsValues = &logicalAttributes->textMetricsValues(); 362 unsigned textMetricsSize = textMetricsValues->size(); 363 while (true) { 364 if (m_logicalMetricsListOffset == textMetricsSize) { 365 if (!currentLogicalCharacterAttributes(logicalAttributes)) 366 return false; 367 368 textMetricsValues = &logicalAttributes->textMetricsValues(); 369 textMetricsSize = textMetricsValues->size(); 370 continue; 371 } 372 373 ASSERT(textMetricsSize); 374 ASSERT(m_logicalMetricsListOffset < textMetricsSize); 375 logicalMetrics = textMetricsValues->at(m_logicalMetricsListOffset); 376 if (logicalMetrics.isEmpty() || (!logicalMetrics.width() && !logicalMetrics.height())) { 377 advanceToNextLogicalCharacter(logicalMetrics); 378 continue; 379 } 380 381 // Stop if we found the next valid logical text metrics object. 382 return true; 383 } 384 385 ASSERT_NOT_REACHED(); 386 return true; 387} 388 389bool SVGTextLayoutEngine::currentVisualCharacterMetrics(SVGInlineTextBox* textBox, const Vector<SVGTextMetrics>& visualMetricsValues, SVGTextMetrics& visualMetrics) 390{ 391 ASSERT(!visualMetricsValues.isEmpty()); 392 unsigned textMetricsSize = visualMetricsValues.size(); 393 unsigned boxStart = textBox->start(); 394 unsigned boxLength = textBox->len(); 395 396 while (m_visualMetricsListOffset < textMetricsSize) { 397 // Advance to text box start location. 398 if (m_visualCharacterOffset < boxStart) { 399 advanceToNextVisualCharacter(visualMetricsValues[m_visualMetricsListOffset]); 400 continue; 401 } 402 403 // Stop if we've finished processing this text box. 404 if (m_visualCharacterOffset >= boxStart + boxLength) 405 return false; 406 407 visualMetrics = visualMetricsValues[m_visualMetricsListOffset]; 408 return true; 409 } 410 411 return false; 412} 413 414void SVGTextLayoutEngine::advanceToNextLogicalCharacter(const SVGTextMetrics& logicalMetrics) 415{ 416 ++m_logicalMetricsListOffset; 417 m_logicalCharacterOffset += logicalMetrics.length(); 418} 419 420void SVGTextLayoutEngine::advanceToNextVisualCharacter(const SVGTextMetrics& visualMetrics) 421{ 422 ++m_visualMetricsListOffset; 423 m_visualCharacterOffset += visualMetrics.length(); 424} 425 426void SVGTextLayoutEngine::layoutTextOnLineOrPath(SVGInlineTextBox* textBox, const RenderSVGInlineText& text, const RenderStyle& style) 427{ 428 if (m_inPathLayout && !m_textPathCalculator) 429 return; 430 431 SVGElement* lengthContext = toSVGElement(text.parent()->node()); 432 433 RenderObject* textParent = text.parent(); 434 bool definesTextLength = textParent ? parentDefinesTextLength(textParent) : false; 435 436 const SVGRenderStyle& svgStyle = style.svgStyle(); 437 438 m_visualMetricsListOffset = 0; 439 m_visualCharacterOffset = 0; 440 441 const Vector<SVGTextMetrics>& visualMetricsValues = text.layoutAttributes()->textMetricsValues(); 442 ASSERT(!visualMetricsValues.isEmpty()); 443 444 const Font& font = style.font(); 445 446 SVGTextLayoutEngineSpacing spacingLayout(font, style.effectiveZoom()); 447 SVGTextLayoutEngineBaseline baselineLayout(font); 448 449 bool didStartTextFragment = false; 450 bool applySpacingToNextCharacter = false; 451 452 float lastAngle = 0; 453 float baselineShift = baselineLayout.calculateBaselineShift(svgStyle, lengthContext); 454 baselineShift -= baselineLayout.calculateAlignmentBaselineShift(m_isVerticalText, &text); 455 456 // Main layout algorithm. 457 while (true) { 458 // Find the start of the current text box in this list, respecting ligatures. 459 SVGTextMetrics visualMetrics(SVGTextMetrics::SkippedSpaceMetrics); 460 if (!currentVisualCharacterMetrics(textBox, visualMetricsValues, visualMetrics)) 461 break; 462 463 if (visualMetrics.isEmpty()) { 464 advanceToNextVisualCharacter(visualMetrics); 465 continue; 466 } 467 468 SVGTextLayoutAttributes* logicalAttributes = 0; 469 if (!currentLogicalCharacterAttributes(logicalAttributes)) 470 break; 471 472 ASSERT(logicalAttributes); 473 SVGTextMetrics logicalMetrics(SVGTextMetrics::SkippedSpaceMetrics); 474 if (!currentLogicalCharacterMetrics(logicalAttributes, logicalMetrics)) 475 break; 476 477 SVGCharacterDataMap& characterDataMap = logicalAttributes->characterDataMap(); 478 SVGCharacterData data; 479 SVGCharacterDataMap::iterator it = characterDataMap.find(m_logicalCharacterOffset + 1); 480 if (it != characterDataMap.end()) 481 data = it->value; 482 483 float x = data.x; 484 float y = data.y; 485 486 // When we've advanced to the box start offset, determine using the original x/y values, 487 // whether this character starts a new text chunk, before doing any further processing. 488 if (m_visualCharacterOffset == textBox->start()) 489 textBox->setStartsNewTextChunk(logicalAttributes->context()->characterStartsNewTextChunk(m_logicalCharacterOffset)); 490 491 float angle = data.rotate == SVGTextLayoutAttributes::emptyValue() ? 0 : data.rotate; 492 493 // Calculate glyph orientation angle. 494 UChar currentCharacter = text.characterAt(m_visualCharacterOffset); 495 float orientationAngle = baselineLayout.calculateGlyphOrientationAngle(m_isVerticalText, svgStyle, currentCharacter); 496 497 // Calculate glyph advance & x/y orientation shifts. 498 float xOrientationShift = 0; 499 float yOrientationShift = 0; 500 float glyphAdvance = baselineLayout.calculateGlyphAdvanceAndOrientation(m_isVerticalText, visualMetrics, orientationAngle, xOrientationShift, yOrientationShift); 501 502 // Assign current text position to x/y values, if needed. 503 updateCharacterPositionIfNeeded(x, y); 504 505 // Apply dx/dy value adjustments to current text position, if needed. 506 updateRelativePositionAdjustmentsIfNeeded(data.dx, data.dy); 507 508 // Calculate SVG Fonts kerning, if needed. 509 float kerning = spacingLayout.calculateSVGKerning(m_isVerticalText, visualMetrics.glyph()); 510 511 // Calculate CSS 'letter-spacing' and 'word-spacing' for next character, if needed. 512 float spacing = spacingLayout.calculateCSSSpacing(currentCharacter); 513 514 float textPathOffset = 0; 515 if (m_inPathLayout) { 516 float scaledGlyphAdvance = glyphAdvance * m_textPathScaling; 517 if (m_isVerticalText) { 518 // If there's an absolute y position available, it marks the beginning of a new position along the path. 519 if (y != SVGTextLayoutAttributes::emptyValue()) 520 m_textPathCurrentOffset = y + m_textPathStartOffset; 521 522 m_textPathCurrentOffset += m_dy - kerning; 523 m_dy = 0; 524 525 // Apply dx/dy correction and setup translations that move to the glyph midpoint. 526 xOrientationShift += m_dx + baselineShift; 527 yOrientationShift -= scaledGlyphAdvance / 2; 528 } else { 529 // If there's an absolute x position available, it marks the beginning of a new position along the path. 530 if (x != SVGTextLayoutAttributes::emptyValue()) 531 m_textPathCurrentOffset = x + m_textPathStartOffset; 532 533 m_textPathCurrentOffset += m_dx - kerning; 534 m_dx = 0; 535 536 // Apply dx/dy correction and setup translations that move to the glyph midpoint. 537 xOrientationShift -= scaledGlyphAdvance / 2; 538 yOrientationShift += m_dy - baselineShift; 539 } 540 541 // Calculate current offset along path. 542 textPathOffset = m_textPathCurrentOffset + scaledGlyphAdvance / 2; 543 544 // Move to next character. 545 m_textPathCurrentOffset += scaledGlyphAdvance + m_textPathSpacing + spacing * m_textPathScaling; 546 547 // Skip character, if we're before the path. 548 if (textPathOffset < 0) { 549 advanceToNextLogicalCharacter(logicalMetrics); 550 advanceToNextVisualCharacter(visualMetrics); 551 continue; 552 } 553 554 // Stop processing, if the next character lies behind the path. 555 if (textPathOffset > m_textPathLength) 556 break; 557 558 FloatPoint point; 559 bool ok = m_textPathCalculator->pointAndNormalAtLength(textPathOffset, point, angle); 560 ASSERT_UNUSED(ok, ok); 561 x = point.x(); 562 y = point.y(); 563 564 // For vertical text on path, the actual angle has to be rotated 90 degrees anti-clockwise, not the orientation angle! 565 if (m_isVerticalText) 566 angle -= 90; 567 } else { 568 // Apply all previously calculated shift values. 569 if (m_isVerticalText) { 570 x += baselineShift; 571 y -= kerning; 572 } else { 573 x -= kerning; 574 y -= baselineShift; 575 } 576 577 x += m_dx; 578 y += m_dy; 579 } 580 581 // Determine whether we have to start a new fragment. 582 bool shouldStartNewFragment = m_dx || m_dy || m_isVerticalText || m_inPathLayout || angle || angle != lastAngle 583 || orientationAngle || kerning || applySpacingToNextCharacter || definesTextLength; 584 585 // If we already started a fragment, close it now. 586 if (didStartTextFragment && shouldStartNewFragment) { 587 applySpacingToNextCharacter = false; 588 recordTextFragment(textBox, visualMetricsValues); 589 } 590 591 // Eventually start a new fragment, if not yet done. 592 if (!didStartTextFragment || shouldStartNewFragment) { 593 ASSERT(!m_currentTextFragment.characterOffset); 594 ASSERT(!m_currentTextFragment.length); 595 596 didStartTextFragment = true; 597 m_currentTextFragment.characterOffset = m_visualCharacterOffset; 598 m_currentTextFragment.metricsListOffset = m_visualMetricsListOffset; 599 m_currentTextFragment.x = x; 600 m_currentTextFragment.y = y; 601 602 // Build fragment transformation. 603 if (angle) 604 m_currentTextFragment.transform.rotate(angle); 605 606 if (xOrientationShift || yOrientationShift) 607 m_currentTextFragment.transform.translate(xOrientationShift, yOrientationShift); 608 609 if (orientationAngle) 610 m_currentTextFragment.transform.rotate(orientationAngle); 611 612 m_currentTextFragment.isTextOnPath = m_inPathLayout && m_textPathScaling != 1; 613 if (m_currentTextFragment.isTextOnPath) { 614 if (m_isVerticalText) 615 m_currentTextFragment.lengthAdjustTransform.scaleNonUniform(1, m_textPathScaling); 616 else 617 m_currentTextFragment.lengthAdjustTransform.scaleNonUniform(m_textPathScaling, 1); 618 } 619 } 620 621 // Update current text position, after processing of the current character finished. 622 if (m_inPathLayout) 623 updateCurrentTextPosition(x, y, glyphAdvance); 624 else { 625 // Apply CSS 'kerning', 'letter-spacing' and 'word-spacing' to next character, if needed. 626 if (spacing) 627 applySpacingToNextCharacter = true; 628 629 float xNew = x - m_dx; 630 float yNew = y - m_dy; 631 632 if (m_isVerticalText) 633 xNew -= baselineShift; 634 else 635 yNew += baselineShift; 636 637 updateCurrentTextPosition(xNew, yNew, glyphAdvance + spacing); 638 } 639 640 advanceToNextLogicalCharacter(logicalMetrics); 641 advanceToNextVisualCharacter(visualMetrics); 642 lastAngle = angle; 643 } 644 645 if (!didStartTextFragment) 646 return; 647 648 // Close last open fragment, if needed. 649 recordTextFragment(textBox, visualMetricsValues); 650} 651 652} 653