FCL/sf/mw/qtwebkit: comparison WebCore/rendering/RenderBlockLineLayout.cpp

equal deleted inserted replaced

--1:000000000000
+:4f2f89ce4247
+/*
+* Copyright (C) 2000 Lars Knoll (knoll@kde.org)
+* Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010 Apple Inc. All right reserved.
+* Copyright (C) 2010 Google Inc. All rights reserved.
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Library General Public
+* License as published by the Free Software Foundation; either
+* version 2 of the License, or (at your option) any later version.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Library General Public License for more details.
+*
+* You should have received a copy of the GNU Library General Public License
+* along with this library; see the file COPYING.LIB.  If not, write to
+* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+* Boston, MA 02110-1301, USA.
+*
+*/
+#include "config.h"
+#include "BidiResolver.h"
+#include "CharacterNames.h"
+#include "Hyphenation.h"
+#include "InlineIterator.h"
+#include "InlineTextBox.h"
+#include "Logging.h"
+#include "RenderArena.h"
+#include "RenderInline.h"
+#include "RenderLayer.h"
+#include "RenderListMarker.h"
+#include "RenderView.h"
+#include "TrailingFloatsRootInlineBox.h"
+#include "break_lines.h"
+#include <wtf/AlwaysInline.h>
+#include <wtf/RefCountedLeakCounter.h>
+#include <wtf/StdLibExtras.h>
+#include <wtf/Vector.h>
+#if ENABLE(SVG)
+#include "SVGRootInlineBox.h"
+#endif
+using namespace std;
+using namespace WTF;
+using namespace Unicode;
+namespace WebCore {
+// We don't let our line box tree for a single line get any deeper than this.
+const unsigned cMaxLineDepth = 200;
+static int getBorderPaddingMargin(RenderBoxModelObject* child, bool endOfInline)
+{
+bool leftSide = (child->style()->direction() == LTR) ? !endOfInline : endOfInline;
+if (leftSide)
+return child->marginLeft() + child->paddingLeft() + child->borderLeft();
+return child->marginRight() + child->paddingRight() + child->borderRight();
+}
+static int inlineWidth(RenderObject* child, bool start = true, bool end = true)
+{
+unsigned lineDepth = 1;
+int extraWidth = 0;
+RenderObject* parent = child->parent();
+while (parent->isInline() && !parent->isInlineBlockOrInlineTable() && lineDepth++ < cMaxLineDepth) {
+if (start && !child->previousSibling())
+extraWidth += getBorderPaddingMargin(toRenderBoxModelObject(parent), false);
+if (end && !child->nextSibling())
+extraWidth += getBorderPaddingMargin(toRenderBoxModelObject(parent), true);
+child = parent;
+parent = child->parent();
+}
+return extraWidth;
+}
+static void chopMidpointsAt(LineMidpointState& lineMidpointState, RenderObject* obj, unsigned pos)
+{
+if (!lineMidpointState.numMidpoints)
+return;
+InlineIterator* midpoints = lineMidpointState.midpoints.data();
+for (int i = lineMidpointState.numMidpoints - 1; i >= 0; i--) {
+const InlineIterator& point = midpoints[i];
+if (point.obj == obj && point.pos == pos) {
+lineMidpointState.numMidpoints = i;
+break;
+}
+}
+}
+static void checkMidpoints(LineMidpointState& lineMidpointState, InlineIterator& lBreak)
+{
+// Check to see if our last midpoint is a start point beyond the line break.  If so,
+// shave it off the list, and shave off a trailing space if the previous end point doesn't
+// preserve whitespace.
+if (lBreak.obj && lineMidpointState.numMidpoints && !(lineMidpointState.numMidpoints % 2)) {
+InlineIterator* midpoints = lineMidpointState.midpoints.data();
+InlineIterator& endpoint = midpoints[lineMidpointState.numMidpoints - 2];
+const InlineIterator& startpoint = midpoints[lineMidpointState.numMidpoints - 1];
+InlineIterator currpoint = endpoint;
+while (!currpoint.atEnd() && currpoint != startpoint && currpoint != lBreak)
+currpoint.increment();
+if (currpoint == lBreak) {
+// We hit the line break before the start point.  Shave off the start point.
+lineMidpointState.numMidpoints--;
+if (endpoint.obj->style()->collapseWhiteSpace()) {
+if (endpoint.obj->isText()) {
+// Don't shave a character off the endpoint if it was from a soft hyphen.
+RenderText* textObj = toRenderText(endpoint.obj);
+if (endpoint.pos + 1 < textObj->textLength()) {
+if (textObj->characters()[endpoint.pos+1] == softHyphen)
+return;
+} else if (startpoint.obj->isText()) {
+RenderText *startText = toRenderText(startpoint.obj);
+if (startText->textLength() && startText->characters()[0] == softHyphen)
+return;
+}
+}
+endpoint.pos--;
+}
+}
+}
+}
+static void addMidpoint(LineMidpointState& lineMidpointState, const InlineIterator& midpoint)
+{
+if (lineMidpointState.midpoints.size() <= lineMidpointState.numMidpoints)
+lineMidpointState.midpoints.grow(lineMidpointState.numMidpoints + 10);
+InlineIterator* midpoints = lineMidpointState.midpoints.data();
+midpoints[lineMidpointState.numMidpoints++] = midpoint;
+}
+void RenderBlock::appendRunsForObject(int start, int end, RenderObject* obj, InlineBidiResolver& resolver)
+{
+if (start > end || obj->isFloating() ||
+(obj->isPositioned() && !obj->style()->hasStaticX() && !obj->style()->hasStaticY() && !obj->container()->isRenderInline()))
+return;
+LineMidpointState& lineMidpointState = resolver.midpointState();
+bool haveNextMidpoint = (lineMidpointState.currentMidpoint < lineMidpointState.numMidpoints);
+InlineIterator nextMidpoint;
+if (haveNextMidpoint)
+nextMidpoint = lineMidpointState.midpoints[lineMidpointState.currentMidpoint];
+if (lineMidpointState.betweenMidpoints) {
+if (!(haveNextMidpoint && nextMidpoint.obj == obj))
+return;
+// This is a new start point. Stop ignoring objects and
+// adjust our start.
+lineMidpointState.betweenMidpoints = false;
+start = nextMidpoint.pos;
+lineMidpointState.currentMidpoint++;
+if (start < end)
+return appendRunsForObject(start, end, obj, resolver);
+} else {
+if (!haveNextMidpoint || (obj != nextMidpoint.obj)) {
+resolver.addRun(new (obj->renderArena()) BidiRun(start, end, obj, resolver.context(), resolver.dir()));
+return;
+}
+// An end midpoint has been encountered within our object.  We
+// need to go ahead and append a run with our endpoint.
+if (static_cast<int>(nextMidpoint.pos + 1) <= end) {
+lineMidpointState.betweenMidpoints = true;
+lineMidpointState.currentMidpoint++;
+if (nextMidpoint.pos != UINT_MAX) { // UINT_MAX means stop at the object and don't include any of it.
+if (static_cast<int>(nextMidpoint.pos + 1) > start)
+resolver.addRun(new (obj->renderArena())
+BidiRun(start, nextMidpoint.pos + 1, obj, resolver.context(), resolver.dir()));
+return appendRunsForObject(nextMidpoint.pos + 1, end, obj, resolver);
+}
+} else
+resolver.addRun(new (obj->renderArena()) BidiRun(start, end, obj, resolver.context(), resolver.dir()));
+}
+}
+static inline InlineBox* createInlineBoxForRenderer(RenderObject* obj, bool isRootLineBox, bool isOnlyRun = false)
+{
+if (isRootLineBox)
+return toRenderBlock(obj)->createAndAppendRootInlineBox();
+if (obj->isText()) {
+InlineTextBox* textBox = toRenderText(obj)->createInlineTextBox();
+// We only treat a box as text for a <br> if we are on a line by ourself or in strict mode
+// (Note the use of strict mode.  In "almost strict" mode, we don't treat the box for <br> as text.)
+if (obj->isBR())
+textBox->setIsText(isOnlyRun || obj->document()->inStrictMode());
+return textBox;
+}
+if (obj->isBox())
+return toRenderBox(obj)->createInlineBox();
+return toRenderInline(obj)->createAndAppendInlineFlowBox();
+}
+static inline void dirtyLineBoxesForRenderer(RenderObject* o, bool fullLayout)
+{
+if (o->isText()) {
+if (o->prefWidthsDirty() && o->isCounter())
+toRenderText(o)->calcPrefWidths(0); // FIXME: Counters depend on this hack. No clue why. Should be investigated and removed.
+toRenderText(o)->dirtyLineBoxes(fullLayout);
+} else
+toRenderInline(o)->dirtyLineBoxes(fullLayout);
+}
+InlineFlowBox* RenderBlock::createLineBoxes(RenderObject* obj, bool firstLine)
+{
+// See if we have an unconstructed line box for this object that is also
+// the last item on the line.
+unsigned lineDepth = 1;
+InlineFlowBox* childBox = 0;
+InlineFlowBox* parentBox = 0;
+InlineFlowBox* result = 0;
+do {
+ASSERT(obj->isRenderInline() || obj == this);
+// Get the last box we made for this render object.
+parentBox = obj->isRenderInline() ? toRenderInline(obj)->lastLineBox() : toRenderBlock(obj)->lastLineBox();
+// If this box is constructed then it is from a previous line, and we need
+// to make a new box for our line.  If this box is unconstructed but it has
+// something following it on the line, then we know we have to make a new box
+// as well.  In this situation our inline has actually been split in two on
+// the same line (this can happen with very fancy language mixtures).
+bool constructedNewBox = false;
+if (!parentBox || parentBox->isConstructed() || parentBox->nextOnLine()) {
+// We need to make a new box for this render object.  Once
+// made, we need to place it at the end of the current line.
+InlineBox* newBox = createInlineBoxForRenderer(obj, obj == this);
+ASSERT(newBox->isInlineFlowBox());
+parentBox = static_cast<InlineFlowBox*>(newBox);
+parentBox->setFirstLineStyleBit(firstLine);
+constructedNewBox = true;
+}
+if (!result)
+result = parentBox;
+// If we have hit the block itself, then |box| represents the root
+// inline box for the line, and it doesn't have to be appended to any parent
+// inline.
+if (childBox)
+parentBox->addToLine(childBox);
+if (!constructedNewBox || obj == this)
+break;
+childBox = parentBox;
+// If we've exceeded our line depth, then jump straight to the root and skip all the remaining
+// intermediate inline flows.
+obj = (++lineDepth >= cMaxLineDepth) ? this : obj->parent();
+} while (true);
+return result;
+}
+RootInlineBox* RenderBlock::constructLine(unsigned runCount, BidiRun* firstRun, BidiRun* lastRun, bool firstLine, bool lastLine, RenderObject* endObject)
+{
+ASSERT(firstRun);
+InlineFlowBox* parentBox = 0;
+for (BidiRun* r = firstRun; r; r = r->next()) {
+// Create a box for our object.
+bool isOnlyRun = (runCount == 1);
+if (runCount == 2 && !r->m_object->isListMarker())
+isOnlyRun = ((style()->direction() == RTL) ? lastRun : firstRun)->m_object->isListMarker();
+InlineBox* box = createInlineBoxForRenderer(r->m_object, false, isOnlyRun);
+r->m_box = box;
+ASSERT(box);
+if (!box)
+continue;
+// If we have no parent box yet, or if the run is not simply a sibling,
+// then we need to construct inline boxes as necessary to properly enclose the
+// run's inline box.
+if (!parentBox || parentBox->renderer() != r->m_object->parent())
+// Create new inline boxes all the way back to the appropriate insertion point.
+parentBox = createLineBoxes(r->m_object->parent(), firstLine);
+// Append the inline box to this line.
+parentBox->addToLine(box);
+bool visuallyOrdered = r->m_object->style()->visuallyOrdered();
+box->setBidiLevel(visuallyOrdered ? 0 : r->level());
+if (box->isInlineTextBox()) {
+InlineTextBox* text = static_cast<InlineTextBox*>(box);
+text->setStart(r->m_start);
+text->setLen(r->m_stop - r->m_start);
+text->m_dirOverride = r->dirOverride(visuallyOrdered);
+if (r->m_hasHyphen)
+text->setHasHyphen(true);
+}
+}
+// We should have a root inline box.  It should be unconstructed and
+// be the last continuation of our line list.
+ASSERT(lastLineBox() && !lastLineBox()->isConstructed());
+// Set bits on our inline flow boxes that indicate which sides should
+// paint borders/margins/padding.  This knowledge will ultimately be used when
+// we determine the horizontal positions and widths of all the inline boxes on
+// the line.
+lastLineBox()->determineSpacingForFlowBoxes(lastLine, endObject);
+// Now mark the line boxes as being constructed.
+lastLineBox()->setConstructed();
+// Return the last line.
+return lastRootBox();
+}
+void RenderBlock::computeHorizontalPositionsForLine(RootInlineBox* lineBox, bool firstLine, BidiRun* firstRun, BidiRun* trailingSpaceRun, bool reachedEnd, GlyphOverflowAndFallbackFontsMap& textBoxDataMap)
+{
+// First determine our total width.
+int availableWidth = lineWidth(height(), firstLine);
+int totWidth = lineBox->getFlowSpacingWidth();
+bool needsWordSpacing = false;
+unsigned numSpaces = 0;
+ETextAlign textAlign = style()->textAlign();
+for (BidiRun* r = firstRun; r; r = r->next()) {
+if (!r->m_box || r->m_object->isPositioned() || r->m_box->isLineBreak())
+continue; // Positioned objects are only participating to figure out their
+// correct static x position.  They have no effect on the width.
+// Similarly, line break boxes have no effect on the width.
+if (r->m_object->isText()) {
+RenderText* rt = toRenderText(r->m_object);
+if (textAlign == JUSTIFY && r != trailingSpaceRun) {
+const UChar* characters = rt->characters();
+for (int i = r->m_start; i < r->m_stop; i++) {
+UChar c = characters[i];
+if (c == ' ' || c == '\n' || c == '\t')
+numSpaces++;
+}
+}
+if (int length = rt->textLength()) {
+if (!r->m_start && needsWordSpacing && isSpaceOrNewline(rt->characters()[r->m_start]))
+totWidth += rt->style(firstLine)->font().wordSpacing();
+needsWordSpacing = !isSpaceOrNewline(rt->characters()[r->m_stop - 1]) && r->m_stop == length;
+}
+HashSet<const SimpleFontData*> fallbackFonts;
+GlyphOverflow glyphOverflow;
+int hyphenWidth = 0;
+if (static_cast<InlineTextBox*>(r->m_box)->hasHyphen()) {
+const AtomicString& hyphenString = rt->style()->hyphenString();
+hyphenWidth = rt->style(firstLine)->font().width(TextRun(hyphenString.characters(), hyphenString.length()));
+}
+r->m_box->setWidth(rt->width(r->m_start, r->m_stop - r->m_start, totWidth, firstLine, &fallbackFonts, &glyphOverflow) + hyphenWidth);
+if (!fallbackFonts.isEmpty()) {
+ASSERT(r->m_box->isText());
+GlyphOverflowAndFallbackFontsMap::iterator it = textBoxDataMap.add(static_cast<InlineTextBox*>(r->m_box), make_pair(Vector<const SimpleFontData*>(), GlyphOverflow())).first;
+ASSERT(it->second.first.isEmpty());
+copyToVector(fallbackFonts, it->second.first);
+}
+if ((glyphOverflow.top || glyphOverflow.bottom || glyphOverflow.left || glyphOverflow.right)) {
+ASSERT(r->m_box->isText());
+GlyphOverflowAndFallbackFontsMap::iterator it = textBoxDataMap.add(static_cast<InlineTextBox*>(r->m_box), make_pair(Vector<const SimpleFontData*>(), GlyphOverflow())).first;
+it->second.second = glyphOverflow;
+}
+} else if (!r->m_object->isRenderInline()) {
+RenderBox* renderBox = toRenderBox(r->m_object);
+renderBox->calcWidth();
+r->m_box->setWidth(renderBox->width());
+totWidth += renderBox->marginLeft() + renderBox->marginRight();
+}
+totWidth += r->m_box->width();
+}
+// Armed with the total width of the line (without justification),
+// we now examine our text-align property in order to determine where to position the
+// objects horizontally.  The total width of the line can be increased if we end up
+// justifying text.
+int x = leftOffset(height(), firstLine);
+switch (textAlign) {
+case LEFT:
+case WEBKIT_LEFT:
+// The direction of the block should determine what happens with wide lines.  In
+// particular with RTL blocks, wide lines should still spill out to the left.
+if (style()->direction() == LTR) {
+if (totWidth > availableWidth && trailingSpaceRun)
+trailingSpaceRun->m_box->setWidth(max(0, trailingSpaceRun->m_box->width() - totWidth + availableWidth));
+} else {
+if (trailingSpaceRun)
+trailingSpaceRun->m_box->setWidth(0);
+else if (totWidth > availableWidth)
+x -= (totWidth - availableWidth);
+}
+break;
+case JUSTIFY:
+if (numSpaces && !reachedEnd && !lineBox->endsWithBreak()) {
+if (trailingSpaceRun) {
+totWidth -= trailingSpaceRun->m_box->width();
+trailingSpaceRun->m_box->setWidth(0);
+}
+break;
+}
+// fall through
+case TAAUTO:
+numSpaces = 0;
+// for right to left fall through to right aligned
+if (style()->direction() == LTR) {
+if (totWidth > availableWidth && trailingSpaceRun)
+trailingSpaceRun->m_box->setWidth(max(0, trailingSpaceRun->m_box->width() - totWidth + availableWidth));
+break;
+}
+case RIGHT:
+case WEBKIT_RIGHT:
+// Wide lines spill out of the block based off direction.
+// So even if text-align is right, if direction is LTR, wide lines should overflow out of the right
+// side of the block.
+if (style()->direction() == LTR) {
+if (trailingSpaceRun) {
+totWidth -= trailingSpaceRun->m_box->width();
+trailingSpaceRun->m_box->setWidth(0);
+}
+if (totWidth < availableWidth)
+x += availableWidth - totWidth;
+} else {
+if (totWidth > availableWidth && trailingSpaceRun) {
+trailingSpaceRun->m_box->setWidth(max(0, trailingSpaceRun->m_box->width() - totWidth + availableWidth));
+totWidth -= trailingSpaceRun->m_box->width();
+} else
+x += availableWidth - totWidth;
+}
+break;
+case CENTER:
+case WEBKIT_CENTER:
+int trailingSpaceWidth = 0;
+if (trailingSpaceRun) {
+totWidth -= trailingSpaceRun->m_box->width();
+trailingSpaceWidth = min(trailingSpaceRun->m_box->width(), (availableWidth - totWidth + 1) / 2);
+trailingSpaceRun->m_box->setWidth(max(0, trailingSpaceWidth));
+}
+if (style()->direction() == LTR)
+x += max((availableWidth - totWidth) / 2, 0);
+else
+x += totWidth > availableWidth ? (availableWidth - totWidth) : (availableWidth - totWidth) / 2 - trailingSpaceWidth;
+break;
+}
+if (numSpaces) {
+for (BidiRun* r = firstRun; r; r = r->next()) {
+if (!r->m_box || r == trailingSpaceRun)
+continue;
+int spaceAdd = 0;
+if (r->m_object->isText()) {
+unsigned spaces = 0;
+const UChar* characters = toRenderText(r->m_object)->characters();
+for (int i = r->m_start; i < r->m_stop; i++) {
+UChar c = characters[i];
+if (c == ' ' || c == '\n' || c == '\t')
+spaces++;
+}
+ASSERT(spaces <= numSpaces);
+// Only justify text if whitespace is collapsed.
+if (r->m_object->style()->collapseWhiteSpace()) {
+spaceAdd = (availableWidth - totWidth) * spaces / numSpaces;
+static_cast<InlineTextBox*>(r->m_box)->setSpaceAdd(spaceAdd);
+totWidth += spaceAdd;
+}
+numSpaces -= spaces;
+if (!numSpaces)
+break;
+}
+}
+}
+// The widths of all runs are now known.  We can now place every inline box (and
+// compute accurate widths for the inline flow boxes).
+needsWordSpacing = false;
+lineBox->placeBoxesHorizontally(x, needsWordSpacing, textBoxDataMap);
+}
+void RenderBlock::computeVerticalPositionsForLine(RootInlineBox* lineBox, BidiRun* firstRun, GlyphOverflowAndFallbackFontsMap& textBoxDataMap)
+{
+setHeight(lineBox->verticallyAlignBoxes(height(), textBoxDataMap));
+lineBox->setBlockHeight(height());
+// Now make sure we place replaced render objects correctly.
+for (BidiRun* r = firstRun; r; r = r->next()) {
+ASSERT(r->m_box);
+if (!r->m_box)
+continue; // Skip runs with no line boxes.
+// Align positioned boxes with the top of the line box.  This is
+// a reasonable approximation of an appropriate y position.
+if (r->m_object->isPositioned())
+r->m_box->setY(height());
+// Position is used to properly position both replaced elements and
+// to update the static normal flow x/y of positioned elements.
+if (r->m_object->isText())
+toRenderText(r->m_object)->positionLineBox(r->m_box);
+else if (r->m_object->isBox())
+toRenderBox(r->m_object)->positionLineBox(r->m_box);
+}
+// Positioned objects and zero-length text nodes destroy their boxes in
+// position(), which unnecessarily dirties the line.
+lineBox->markDirty(false);
+}
+static inline bool isCollapsibleSpace(UChar character, RenderText* renderer)
+{
+if (character == ' ' || character == '\t' || character == softHyphen)
+return true;
+if (character == '\n')
+return !renderer->style()->preserveNewline();
+if (character == noBreakSpace)
+return renderer->style()->nbspMode() == SPACE;
+return false;
+}
+void RenderBlock::layoutInlineChildren(bool relayoutChildren, int& repaintTop, int& repaintBottom)
+{
+bool useRepaintBounds = false;
+m_overflow.clear();
+setHeight(borderTop() + paddingTop());
+int toAdd = borderBottom() + paddingBottom() + horizontalScrollbarHeight();
+// Figure out if we should clear out our line boxes.
+// FIXME: Handle resize eventually!
+bool fullLayout = !firstLineBox() || selfNeedsLayout() || relayoutChildren;
+if (fullLayout)
+lineBoxes()->deleteLineBoxes(renderArena());
+// Text truncation only kicks in if your overflow isn't visible and your text-overflow-mode isn't
+// clip.
+// FIXME: CSS3 says that descendants that are clipped must also know how to truncate.  This is insanely
+// difficult to figure out (especially in the middle of doing layout), and is really an esoteric pile of nonsense
+// anyway, so we won't worry about following the draft here.
+bool hasTextOverflow = style()->textOverflow() && hasOverflowClip();
+// Walk all the lines and delete our ellipsis line boxes if they exist.
+if (hasTextOverflow)
+deleteEllipsisLineBoxes();
+if (firstChild()) {
+// layout replaced elements
+bool endOfInline = false;
+RenderObject* o = bidiFirst(this, 0, false);
+Vector<FloatWithRect> floats;
+bool hasInlineChild = false;
+while (o) {
+if (o->isReplaced() || o->isFloating() || o->isPositioned()) {
+RenderBox* box = toRenderBox(o);
+if (relayoutChildren || o->style()->width().isPercent() || o->style()->height().isPercent())
+o->setChildNeedsLayout(true, false);
+// If relayoutChildren is set and we have percentage padding, we also need to invalidate the child's pref widths.
+if (relayoutChildren && (o->style()->paddingLeft().isPercent() || o->style()->paddingRight().isPercent()))
+o->setPrefWidthsDirty(true, false);
+if (o->isPositioned())
+o->containingBlock()->insertPositionedObject(box);
+else {
+if (o->isFloating())
+floats.append(FloatWithRect(box));
+else if (fullLayout || o->needsLayout()) // Replaced elements
+toRenderBox(o)->dirtyLineBoxes(fullLayout);
+o->layoutIfNeeded();
+}
+} else if (o->isText() || (o->isRenderInline() && !endOfInline)) {
+hasInlineChild = true;
+if (fullLayout || o->selfNeedsLayout())
+dirtyLineBoxesForRenderer(o, fullLayout);
+o->setNeedsLayout(false);
+if (!o->isText())
+toRenderInline(o)->invalidateVerticalPosition(); // FIXME: Should do better here and not always invalidate everything.
+}
+o = bidiNext(this, o, 0, false, &endOfInline);
+}
+// We want to skip ahead to the first dirty line
+InlineBidiResolver resolver;
+unsigned floatIndex;
+bool firstLine = true;
+bool previousLineBrokeCleanly = true;
+RootInlineBox* startLine = determineStartPosition(firstLine, fullLayout, previousLineBrokeCleanly, resolver, floats, floatIndex);
+if (fullLayout && hasInlineChild && !selfNeedsLayout()) {
+setNeedsLayout(true, false);  // Mark ourselves as needing a full layout. This way we'll repaint like
+// we're supposed to.
+RenderView* v = view();
+if (v && !v->doingFullRepaint() && hasLayer()) {
+// Because we waited until we were already inside layout to discover
+// that the block really needed a full layout, we missed our chance to repaint the layer
+// before layout started.  Luckily the layer has cached the repaint rect for its original
+// position and size, and so we can use that to make a repaint happen now.
+repaintUsingContainer(containerForRepaint(), layer()->repaintRect());
+}
+}
+FloatingObject* lastFloat = m_floatingObjects ? m_floatingObjects->last() : 0;
+LineMidpointState& lineMidpointState = resolver.midpointState();
+// We also find the first clean line and extract these lines.  We will add them back
+// if we determine that we're able to synchronize after handling all our dirty lines.
+InlineIterator cleanLineStart;
+BidiStatus cleanLineBidiStatus;
+int endLineYPos = 0;
+RootInlineBox* endLine = (fullLayout || !startLine) ?
+0 : determineEndPosition(startLine, cleanLineStart, cleanLineBidiStatus, endLineYPos);
+if (startLine) {
+useRepaintBounds = true;
+repaintTop = height();
+repaintBottom = height();
+RenderArena* arena = renderArena();
+RootInlineBox* box = startLine;
+while (box) {
+repaintTop = min(repaintTop, box->topVisibleOverflow());
+repaintBottom = max(repaintBottom, box->bottomVisibleOverflow());
+RootInlineBox* next = box->nextRootBox();
+box->deleteLine(arena);
+box = next;
+}
+}
+InlineIterator end = resolver.position();
+if (!fullLayout && lastRootBox() && lastRootBox()->endsWithBreak()) {
+// If the last line before the start line ends with a line break that clear floats,
+// adjust the height accordingly.
+// A line break can be either the first or the last object on a line, depending on its direction.
+if (InlineBox* lastLeafChild = lastRootBox()->lastLeafChild()) {
+RenderObject* lastObject = lastLeafChild->renderer();
+if (!lastObject->isBR())
+lastObject = lastRootBox()->firstLeafChild()->renderer();
+if (lastObject->isBR()) {
+EClear clear = lastObject->style()->clear();
+if (clear != CNONE)
+newLine(clear);
+}
+}
+}
+bool endLineMatched = false;
+bool checkForEndLineMatch = endLine;
+bool checkForFloatsFromLastLine = false;
+bool isLineEmpty = true;
+while (!end.atEnd()) {
+// FIXME: Is this check necessary before the first iteration or can it be moved to the end?
+if (checkForEndLineMatch && (endLineMatched = matchedEndLine(resolver, cleanLineStart, cleanLineBidiStatus, endLine, endLineYPos, repaintBottom, repaintTop)))
+break;
+lineMidpointState.reset();
+isLineEmpty = true;
+EClear clear = CNONE;
+bool hyphenated;
+end = findNextLineBreak(resolver, firstLine, isLineEmpty, previousLineBrokeCleanly, hyphenated, &clear);
+if (resolver.position().atEnd()) {
+resolver.deleteRuns();
+checkForFloatsFromLastLine = true;
+break;
+}
+ASSERT(end != resolver.position());
+if (!isLineEmpty) {
+resolver.createBidiRunsForLine(end, style()->visuallyOrdered(), previousLineBrokeCleanly);
+ASSERT(resolver.position() == end);
+BidiRun* trailingSpaceRun = 0;
+if (!previousLineBrokeCleanly && resolver.runCount() && resolver.logicallyLastRun()->m_object->style()->breakOnlyAfterWhiteSpace()
+&& resolver.logicallyLastRun()->m_object->style()->autoWrap()) {
+trailingSpaceRun = resolver.logicallyLastRun();
+RenderObject* lastObject = trailingSpaceRun->m_object;
+if (lastObject->isText()) {
+RenderText* lastText = toRenderText(lastObject);
+const UChar* characters = lastText->characters();
+int firstSpace = trailingSpaceRun->stop();
+while (firstSpace > trailingSpaceRun->start()) {
+UChar current = characters[firstSpace - 1];
+if (!isCollapsibleSpace(current, lastText))
+break;
+firstSpace--;
+}
+if (firstSpace == trailingSpaceRun->stop())
+trailingSpaceRun = 0;
+else {
+TextDirection direction = style()->direction();
+bool shouldReorder = trailingSpaceRun != (direction == LTR ? resolver.lastRun() : resolver.firstRun());
+if (firstSpace != trailingSpaceRun->start()) {
+BidiContext* baseContext = resolver.context();
+while (BidiContext* parent = baseContext->parent())
+baseContext = parent;
+BidiRun* newTrailingRun = new (renderArena()) BidiRun(firstSpace, trailingSpaceRun->m_stop, trailingSpaceRun->m_object, baseContext, OtherNeutral);
+trailingSpaceRun->m_stop = firstSpace;
+if (direction == LTR)
+resolver.addRun(newTrailingRun);
+else
+resolver.prependRun(newTrailingRun);
+trailingSpaceRun = newTrailingRun;
+shouldReorder = false;
+}
+if (shouldReorder) {
+if (direction == LTR) {
+resolver.moveRunToEnd(trailingSpaceRun);
+trailingSpaceRun->m_level = 0;
+} else {
+resolver.moveRunToBeginning(trailingSpaceRun);
+trailingSpaceRun->m_level = 1;
+}
+}
+}
+} else
+trailingSpaceRun = 0;
+}
+// Now that the runs have been ordered, we create the line boxes.
+// At the same time we figure out where border/padding/margin should be applied for
+// inline flow boxes.
+RootInlineBox* lineBox = 0;
+if (resolver.runCount()) {
+if (hyphenated)
+resolver.logicallyLastRun()->m_hasHyphen = true;
+lineBox = constructLine(resolver.runCount(), resolver.firstRun(), resolver.lastRun(), firstLine, !end.obj, end.obj && !end.pos ? end.obj : 0);
+if (lineBox) {
+lineBox->setEndsWithBreak(previousLineBrokeCleanly);
+#if ENABLE(SVG)
+bool isSVGRootInlineBox = lineBox->isSVGRootInlineBox();
+#else
+bool isSVGRootInlineBox = false;
+#endif
+GlyphOverflowAndFallbackFontsMap textBoxDataMap;
+// Now we position all of our text runs horizontally.
+if (!isSVGRootInlineBox)
+computeHorizontalPositionsForLine(lineBox, firstLine, resolver.firstRun(), trailingSpaceRun, end.atEnd(), textBoxDataMap);
+// Now position our text runs vertically.
+computeVerticalPositionsForLine(lineBox, resolver.firstRun(), textBoxDataMap);
+#if ENABLE(SVG)
+// SVG text layout code computes vertical & horizontal positions on its own.
+// Note that we still need to execute computeVerticalPositionsForLine() as
+// it calls InlineTextBox::positionLineBox(), which tracks whether the box
+// contains reversed text or not. If we wouldn't do that editing and thus
+// text selection in RTL boxes would not work as expected.
+if (isSVGRootInlineBox) {
+ASSERT(isSVGText());
+static_cast<SVGRootInlineBox*>(lineBox)->computePerCharacterLayoutInformation();
+}
+#endif
+#if PLATFORM(MAC)
+// Highlight acts as an overflow inflation.
+if (style()->highlight() != nullAtom)
+lineBox->addHighlightOverflow();
+#endif
+}
+}
+resolver.deleteRuns();
+if (lineBox) {
+lineBox->setLineBreakInfo(end.obj, end.pos, resolver.status());
+if (useRepaintBounds) {
+repaintTop = min(repaintTop, lineBox->topVisibleOverflow());
+repaintBottom = max(repaintBottom, lineBox->bottomVisibleOverflow());
+}
+}
+firstLine = false;
+newLine(clear);
+}
+if (m_floatingObjects && lastRootBox()) {
+if (lastFloat) {
+for (FloatingObject* f = m_floatingObjects->last(); f != lastFloat; f = m_floatingObjects->prev()) {
+}
+m_floatingObjects->next();
+} else
+m_floatingObjects->first();
+for (FloatingObject* f = m_floatingObjects->current(); f; f = m_floatingObjects->next()) {
+lastRootBox()->floats().append(f->m_renderer);
+ASSERT(f->m_renderer == floats[floatIndex].object);
+// If a float's geometry has changed, give up on syncing with clean lines.
+if (floats[floatIndex].rect != IntRect(f->m_left, f->m_top, f->m_width, f->m_bottom - f->m_top))
+checkForEndLineMatch = false;
+floatIndex++;
+}
+lastFloat = m_floatingObjects->last();
+}
+lineMidpointState.reset();
+resolver.setPosition(end);
+}
+if (endLine) {
+if (endLineMatched) {
+// Attach all the remaining lines, and then adjust their y-positions as needed.
+int delta = height() - endLineYPos;
+for (RootInlineBox* line = endLine; line; line = line->nextRootBox()) {
+line->attachLine();
+if (delta) {
+repaintTop = min(repaintTop, line->topVisibleOverflow() + min(delta, 0));
+repaintBottom = max(repaintBottom, line->bottomVisibleOverflow() + max(delta, 0));
+line->adjustPosition(0, delta);
+}
+if (Vector<RenderBox*>* cleanLineFloats = line->floatsPtr()) {
+Vector<RenderBox*>::iterator end = cleanLineFloats->end();
+for (Vector<RenderBox*>::iterator f = cleanLineFloats->begin(); f != end; ++f) {
+int floatTop = (*f)->y() - (*f)->marginTop();
+insertFloatingObject(*f);
+setHeight(floatTop + delta);
+positionNewFloats();
+}
+}
+}
+setHeight(lastRootBox()->blockHeight());
+} else {
+// Delete all the remaining lines.
+RootInlineBox* line = endLine;
+RenderArena* arena = renderArena();
+while (line) {
+repaintTop = min(repaintTop, line->topVisibleOverflow());
+repaintBottom = max(repaintBottom, line->bottomVisibleOverflow());
+RootInlineBox* next = line->nextRootBox();
+line->deleteLine(arena);
+line = next;
+}
+}
+}
+if (m_floatingObjects && (checkForFloatsFromLastLine || positionNewFloats()) && lastRootBox()) {
+// In case we have a float on the last line, it might not be positioned up to now.
+// This has to be done before adding in the bottom border/padding, or the float will
+// include the padding incorrectly. -dwh
+if (checkForFloatsFromLastLine) {
+int bottomVisualOverflow = lastRootBox()->bottomVisualOverflow();
+int bottomLayoutOverflow = lastRootBox()->bottomLayoutOverflow();
+TrailingFloatsRootInlineBox* trailingFloatsLineBox = new (renderArena()) TrailingFloatsRootInlineBox(this);
+m_lineBoxes.appendLineBox(trailingFloatsLineBox);
+trailingFloatsLineBox->setConstructed();
+GlyphOverflowAndFallbackFontsMap textBoxDataMap;
+trailingFloatsLineBox->verticallyAlignBoxes(height(), textBoxDataMap);
+trailingFloatsLineBox->setVerticalOverflowPositions(height(), bottomLayoutOverflow, height(), bottomVisualOverflow, 0);
+trailingFloatsLineBox->setBlockHeight(height());
+}
+if (lastFloat) {
+for (FloatingObject* f = m_floatingObjects->last(); f != lastFloat; f = m_floatingObjects->prev()) {
+}
+m_floatingObjects->next();
+} else
+m_floatingObjects->first();
+for (FloatingObject* f = m_floatingObjects->current(); f; f = m_floatingObjects->next())
+lastRootBox()->floats().append(f->m_renderer);
+lastFloat = m_floatingObjects->last();
+}
+size_t floatCount = floats.size();
+// Floats that did not have layout did not repaint when we laid them out. They would have
+// painted by now if they had moved, but if they stayed at (0, 0), they still need to be
+// painted.
+for (size_t i = 0; i < floatCount; ++i) {
+if (!floats[i].everHadLayout) {
+RenderBox* f = floats[i].object;
+if (!f->x() && !f->y() && f->checkForRepaintDuringLayout())
+f->repaint();
+}
+}
+}
+// Now add in the bottom border/padding.
+setHeight(height() + toAdd);
+if (!firstLineBox() && hasLineIfEmpty())
+setHeight(height() + lineHeight(true, true));
+// See if we have any lines that spill out of our block.  If we do, then we will possibly need to
+// truncate text.
+if (hasTextOverflow)
+checkLinesForTextOverflow();
+}
+RootInlineBox* RenderBlock::determineStartPosition(bool& firstLine, bool& fullLayout, bool& previousLineBrokeCleanly,
+InlineBidiResolver& resolver, Vector<FloatWithRect>& floats, unsigned& numCleanFloats)
+{
+RootInlineBox* curr = 0;
+RootInlineBox* last = 0;
+bool dirtiedByFloat = false;
+if (!fullLayout) {
+size_t floatIndex = 0;
+for (curr = firstRootBox(); curr && !curr->isDirty(); curr = curr->nextRootBox()) {
+if (Vector<RenderBox*>* cleanLineFloats = curr->floatsPtr()) {
+Vector<RenderBox*>::iterator end = cleanLineFloats->end();
+for (Vector<RenderBox*>::iterator o = cleanLineFloats->begin(); o != end; ++o) {
+RenderBox* f = *o;
+IntSize newSize(f->width() + f->marginLeft() +f->marginRight(), f->height() + f->marginTop() + f->marginBottom());
+ASSERT(floatIndex < floats.size());
+if (floats[floatIndex].object != f) {
+// A new float has been inserted before this line or before its last known float.
+// Just do a full layout.
+fullLayout = true;
+break;
+}
+if (floats[floatIndex].rect.size() != newSize) {
+int floatTop = floats[floatIndex].rect.y();
+curr->markDirty();
+markLinesDirtyInVerticalRange(curr->blockHeight(), floatTop + max(floats[floatIndex].rect.height(), newSize.height()), curr);
+floats[floatIndex].rect.setSize(newSize);
+dirtiedByFloat = true;
+}
+floatIndex++;
+}
+}
+if (dirtiedByFloat || fullLayout)
+break;
+}
+// Check if a new float has been inserted after the last known float.
+if (!curr && floatIndex < floats.size())
+fullLayout = true;
+}
+if (fullLayout) {
+// Nuke all our lines.
+if (firstRootBox()) {
+RenderArena* arena = renderArena();
+curr = firstRootBox();
+while (curr) {
+RootInlineBox* next = curr->nextRootBox();
+curr->deleteLine(arena);
+curr = next;
+}
+ASSERT(!firstLineBox() && !lastLineBox());
+}
+} else {
+if (curr) {
+// We have a dirty line.
+if (RootInlineBox* prevRootBox = curr->prevRootBox()) {
+// We have a previous line.
+if (!dirtiedByFloat && (!prevRootBox->endsWithBreak() || (prevRootBox->lineBreakObj()->isText() && prevRootBox->lineBreakPos() >= toRenderText(prevRootBox->lineBreakObj())->textLength())))
+// The previous line didn't break cleanly or broke at a newline
+// that has been deleted, so treat it as dirty too.
+curr = prevRootBox;
+}
+} else {
+// No dirty lines were found.
+// If the last line didn't break cleanly, treat it as dirty.
+if (lastRootBox() && !lastRootBox()->endsWithBreak())
+curr = lastRootBox();
+}
+// If we have no dirty lines, then last is just the last root box.
+last = curr ? curr->prevRootBox() : lastRootBox();
+}
+numCleanFloats = 0;
+if (!floats.isEmpty()) {
+int savedHeight = height();
+// Restore floats from clean lines.
+RootInlineBox* line = firstRootBox();
+while (line != curr) {
+if (Vector<RenderBox*>* cleanLineFloats = line->floatsPtr()) {
+Vector<RenderBox*>::iterator end = cleanLineFloats->end();
+for (Vector<RenderBox*>::iterator f = cleanLineFloats->begin(); f != end; ++f) {
+insertFloatingObject(*f);
+setHeight((*f)->y() - (*f)->marginTop());
+positionNewFloats();
+ASSERT(floats[numCleanFloats].object == *f);
+numCleanFloats++;
+}
+}
+line = line->nextRootBox();
+}
+setHeight(savedHeight);
+}
+firstLine = !last;
+previousLineBrokeCleanly = !last || last->endsWithBreak();
+RenderObject* startObj;
+int pos = 0;
+if (last) {
+setHeight(last->blockHeight());
+startObj = last->lineBreakObj();
+pos = last->lineBreakPos();
+resolver.setStatus(last->lineBreakBidiStatus());
+} else {
+bool ltr = style()->direction() == LTR
+#if ENABLE(SVG)
+|| (style()->unicodeBidi() == UBNormal && isSVGText())
+#endif
+;
+Direction direction = ltr ? LeftToRight : RightToLeft;
+resolver.setLastStrongDir(direction);
+resolver.setLastDir(direction);
+resolver.setEorDir(direction);
+resolver.setContext(BidiContext::create(ltr ? 0 : 1, direction, style()->unicodeBidi() == Override));
+startObj = bidiFirst(this, &resolver);
+}
+resolver.setPosition(InlineIterator(this, startObj, pos));
+return curr;
+}
+RootInlineBox* RenderBlock::determineEndPosition(RootInlineBox* startLine, InlineIterator& cleanLineStart, BidiStatus& cleanLineBidiStatus, int& yPos)
+{
+RootInlineBox* last = 0;
+if (!startLine)
+last = 0;
+else {
+for (RootInlineBox* curr = startLine->nextRootBox(); curr; curr = curr->nextRootBox()) {
+if (curr->isDirty())
+last = 0;
+else if (!last)
+last = curr;
+}
+}
+if (!last)
+return 0;
+RootInlineBox* prev = last->prevRootBox();
+cleanLineStart = InlineIterator(this, prev->lineBreakObj(), prev->lineBreakPos());
+cleanLineBidiStatus = prev->lineBreakBidiStatus();
+yPos = prev->blockHeight();
+for (RootInlineBox* line = last; line; line = line->nextRootBox())
+line->extractLine(); // Disconnect all line boxes from their render objects while preserving
+// their connections to one another.
+return last;
+}
+bool RenderBlock::matchedEndLine(const InlineBidiResolver& resolver, const InlineIterator& endLineStart, const BidiStatus& endLineStatus, RootInlineBox*& endLine, int& endYPos, int& repaintBottom, int& repaintTop)
+{
+if (resolver.position() == endLineStart) {
+if (resolver.status() != endLineStatus)
+return false;
+int delta = height() - endYPos;
+if (!delta || !m_floatingObjects)
+return true;
+// See if any floats end in the range along which we want to shift the lines vertically.
+int top = min(height(), endYPos);
+RootInlineBox* lastLine = endLine;
+while (RootInlineBox* nextLine = lastLine->nextRootBox())
+lastLine = nextLine;
+int bottom = lastLine->blockHeight() + abs(delta);
+for (FloatingObject* f = m_floatingObjects->first(); f; f = m_floatingObjects->next()) {
+if (f->m_bottom >= top && f->m_bottom < bottom)
+return false;
+}
+return true;
+}
+// The first clean line doesn't match, but we can check a handful of following lines to try
+// to match back up.
+static int numLines = 8; // The # of lines we're willing to match against.
+RootInlineBox* line = endLine;
+for (int i = 0; i < numLines && line; i++, line = line->nextRootBox()) {
+if (line->lineBreakObj() == resolver.position().obj && line->lineBreakPos() == resolver.position().pos) {
+// We have a match.
+if (line->lineBreakBidiStatus() != resolver.status())
+return false; // ...but the bidi state doesn't match.
+RootInlineBox* result = line->nextRootBox();
+// Set our yPos to be the block height of endLine.
+if (result)
+endYPos = line->blockHeight();
+int delta = height() - endYPos;
+if (delta && m_floatingObjects) {
+// See if any floats end in the range along which we want to shift the lines vertically.
+int top = min(height(), endYPos);
+RootInlineBox* lastLine = endLine;
+while (RootInlineBox* nextLine = lastLine->nextRootBox())
+lastLine = nextLine;
+int bottom = lastLine->blockHeight() + abs(delta);
+for (FloatingObject* f = m_floatingObjects->first(); f; f = m_floatingObjects->next()) {
+if (f->m_bottom >= top && f->m_bottom < bottom)
+return false;
+}
+}
+// Now delete the lines that we failed to sync.
+RootInlineBox* boxToDelete = endLine;
+RenderArena* arena = renderArena();
+while (boxToDelete && boxToDelete != result) {
+repaintTop = min(repaintTop, boxToDelete->topVisibleOverflow());
+repaintBottom = max(repaintBottom, boxToDelete->bottomVisibleOverflow());
+RootInlineBox* next = boxToDelete->nextRootBox();
+boxToDelete->deleteLine(arena);
+boxToDelete = next;
+}
+endLine = result;
+return result;
+}
+}
+return false;
+}
+static inline bool skipNonBreakingSpace(const InlineIterator& it, bool isLineEmpty, bool previousLineBrokeCleanly)
+{
+if (it.obj->style()->nbspMode() != SPACE || it.current() != noBreakSpace)
+return false;
+// FIXME: This is bad.  It makes nbsp inconsistent with space and won't work correctly
+// with m_minWidth/m_maxWidth.
+// Do not skip a non-breaking space if it is the first character
+// on a line after a clean line break (or on the first line, since previousLineBrokeCleanly starts off
+// |true|).
+if (isLineEmpty && previousLineBrokeCleanly)
+return false;
+return true;
+}
+static inline bool shouldCollapseWhiteSpace(const RenderStyle* style, bool isLineEmpty, bool previousLineBrokeCleanly)
+{
+return style->collapseWhiteSpace() || (style->whiteSpace() == PRE_WRAP && (!isLineEmpty || !previousLineBrokeCleanly));
+}
+static inline bool shouldPreserveNewline(RenderObject* object)
+{
+#if ENABLE(SVG)
+if (object->isSVGInlineText())
+return false;
+#endif
+return object->style()->preserveNewline();
+}
+static bool inlineFlowRequiresLineBox(RenderInline* flow)
+{
+// FIXME: Right now, we only allow line boxes for inlines that are truly empty.
+// We need to fix this, though, because at the very least, inlines containing only
+// ignorable whitespace should should also have line boxes.
+return !flow->firstChild() && flow->hasHorizontalBordersPaddingOrMargin();
+}
+bool RenderBlock::requiresLineBox(const InlineIterator& it, bool isLineEmpty, bool previousLineBrokeCleanly)
+{
+if (it.obj->isFloatingOrPositioned())
+return false;
+if (it.obj->isRenderInline() && !inlineFlowRequiresLineBox(toRenderInline(it.obj)))
+return false;
+if (!shouldCollapseWhiteSpace(it.obj->style(), isLineEmpty, previousLineBrokeCleanly) || it.obj->isBR())
+return true;
+UChar current = it.current();
+return current != ' ' && current != '\t' && current != softHyphen && (current != '\n' || shouldPreserveNewline(it.obj))
+&& !skipNonBreakingSpace(it, isLineEmpty, previousLineBrokeCleanly);
+}
+bool RenderBlock::generatesLineBoxesForInlineChild(RenderObject* inlineObj, bool isLineEmpty, bool previousLineBrokeCleanly)
+{
+ASSERT(inlineObj->parent() == this);
+InlineIterator it(this, inlineObj, 0);
+while (!it.atEnd() && !requiresLineBox(it, isLineEmpty, previousLineBrokeCleanly))
+it.increment();
+return !it.atEnd();
+}
+// FIXME: The entire concept of the skipTrailingWhitespace function is flawed, since we really need to be building
+// line boxes even for containers that may ultimately collapse away.  Otherwise we'll never get positioned
+// elements quite right.  In other words, we need to build this function's work into the normal line
+// object iteration process.
+// NB. this function will insert any floating elements that would otherwise
+// be skipped but it will not position them.
+void RenderBlock::skipTrailingWhitespace(InlineIterator& iterator, bool isLineEmpty, bool previousLineBrokeCleanly)
+{
+while (!iterator.atEnd() && !requiresLineBox(iterator, isLineEmpty, previousLineBrokeCleanly)) {
+RenderObject* object = iterator.obj;
+if (object->isFloating()) {
+insertFloatingObject(toRenderBox(object));
+} else if (object->isPositioned()) {
+// FIXME: The math here is actually not really right.  It's a best-guess approximation that
+// will work for the common cases
+RenderObject* c = object->container();
+if (c->isRenderInline()) {
+// A relative positioned inline encloses us.  In this case, we also have to determine our
+// position as though we were an inline.  Set |staticX| and |staticY| on the relative positioned
+// inline so that we can obtain the value later.
+toRenderInline(c)->layer()->setStaticX(style()->direction() == LTR ? leftOffset(height(), false) : rightOffset(height(), false));
+toRenderInline(c)->layer()->setStaticY(height());
+}
+RenderBox* box = toRenderBox(object);
+if (box->style()->hasStaticX()) {
+if (box->style()->isOriginalDisplayInlineType())
+box->layer()->setStaticX(style()->direction() == LTR ? leftOffset(height(), false) : width() - rightOffset(height(), false));
+else
+box->layer()->setStaticX(style()->direction() == LTR ? borderLeft() + paddingLeft() : borderRight() + paddingRight());
+}
+if (box->style()->hasStaticY())
+box->layer()->setStaticY(height());
+}
+iterator.increment();
+}
+}
+int RenderBlock::skipLeadingWhitespace(InlineBidiResolver& resolver, bool firstLine, bool isLineEmpty, bool previousLineBrokeCleanly)
+{
+int availableWidth = lineWidth(height(), firstLine);
+while (!resolver.position().atEnd() && !requiresLineBox(resolver.position(), isLineEmpty, previousLineBrokeCleanly)) {
+RenderObject* object = resolver.position().obj;
+if (object->isFloating()) {
+insertFloatingObject(toRenderBox(object));
+positionNewFloats();
+availableWidth = lineWidth(height(), firstLine);
+} else if (object->isPositioned()) {
+// FIXME: The math here is actually not really right.  It's a best-guess approximation that
+// will work for the common cases
+RenderObject* c = object->container();
+if (c->isRenderInline()) {
+// A relative positioned inline encloses us.  In this case, we also have to determine our
+// position as though we were an inline.  Set |staticX| and |staticY| on the relative positioned
+// inline so that we can obtain the value later.
+toRenderInline(c)->layer()->setStaticX(style()->direction() == LTR ? leftOffset(height(), firstLine) : rightOffset(height(), firstLine));
+toRenderInline(c)->layer()->setStaticY(height());
+}
+RenderBox* box = toRenderBox(object);
+if (box->style()->hasStaticX()) {
+if (box->style()->isOriginalDisplayInlineType())
+box->layer()->setStaticX(style()->direction() == LTR ? leftOffset(height(), firstLine) : width() - rightOffset(height(), firstLine));
+else
+box->layer()->setStaticX(style()->direction() == LTR ? borderLeft() + paddingLeft() : borderRight() + paddingRight());
+}
+if (box->style()->hasStaticY())
+box->layer()->setStaticY(height());
+}
+resolver.increment();
+}
+resolver.commitExplicitEmbedding();
+return availableWidth;
+}
+// This is currently just used for list markers and inline flows that have line boxes. Neither should
+// have an effect on whitespace at the start of the line.
+static bool shouldSkipWhitespaceAfterStartObject(RenderBlock* block, RenderObject* o, LineMidpointState& lineMidpointState)
+{
+RenderObject* next = bidiNext(block, o);
+if (next && !next->isBR() && next->isText() && toRenderText(next)->textLength() > 0) {
+RenderText* nextText = toRenderText(next);
+UChar nextChar = nextText->characters()[0];
+if (nextText->style()->isCollapsibleWhiteSpace(nextChar)) {
+addMidpoint(lineMidpointState, InlineIterator(0, o, 0));
+return true;
+}
+}
+return false;
+}
+void RenderBlock::fitBelowFloats(int widthToFit, bool firstLine, int& availableWidth)
+{
+ASSERT(widthToFit > availableWidth);
+int floatBottom;
+int lastFloatBottom = height();
+int newLineWidth = availableWidth;
+while (true) {
+floatBottom = nextFloatBottomBelow(lastFloatBottom);
+if (!floatBottom)
+break;
+newLineWidth = lineWidth(floatBottom, firstLine);
+lastFloatBottom = floatBottom;
+if (newLineWidth >= widthToFit)
+break;
+}
+if (newLineWidth > availableWidth) {
+setHeight(lastFloatBottom);
+availableWidth = newLineWidth;
+}
+}
+static inline unsigned textWidth(RenderText* text, unsigned from, unsigned len, const Font& font, int xPos, bool isFixedPitch, bool collapseWhiteSpace)
+{
+if (isFixedPitch || (!from && len == text->textLength()))
+return text->width(from, len, font, xPos);
+return font.width(TextRun(text->characters() + from, len, !collapseWhiteSpace, xPos));
+}
+static void tryHyphenating(RenderText* text, const Font& font, int lastSpace, int pos, int xPos, int availableWidth, bool isFixedPitch, bool collapseWhiteSpace, int lastSpaceWordSpacing, InlineIterator& lineBreak, int nextBreakable, bool& hyphenated)
+{
+const AtomicString& hyphenString = text->style()->hyphenString();
+int hyphenWidth = font.width(TextRun(hyphenString.characters(), hyphenString.length()));
+unsigned prefixLength = font.offsetForPosition(TextRun(text->characters() + lastSpace, pos - lastSpace, !collapseWhiteSpace, xPos + lastSpaceWordSpacing), availableWidth - xPos - hyphenWidth - lastSpaceWordSpacing, false);
+if (!prefixLength)
+return;
+prefixLength = 1 + lastHyphenLocation(text->characters() + lastSpace + 1, pos - lastSpace - 1, prefixLength - 1);
+if (prefixLength <= 1)
+return;
+#if !ASSERT_DISABLED
+int prefixWidth = hyphenWidth + textWidth(text, lastSpace, prefixLength, font, xPos, isFixedPitch, collapseWhiteSpace) + lastSpaceWordSpacing;
+ASSERT(xPos + prefixWidth <= availableWidth);
+#else
+UNUSED_PARAM(isFixedPitch);
+#endif
+lineBreak.obj = text;
+lineBreak.pos = lastSpace + prefixLength;
+lineBreak.nextBreakablePosition = nextBreakable;
+hyphenated = true;
+}
+InlineIterator RenderBlock::findNextLineBreak(InlineBidiResolver& resolver, bool firstLine,  bool& isLineEmpty, bool& previousLineBrokeCleanly,
+bool& hyphenated, EClear* clear)
+{
+ASSERT(resolver.position().block == this);
+bool appliedStartWidth = resolver.position().pos > 0;
+LineMidpointState& lineMidpointState = resolver.midpointState();
+int width = skipLeadingWhitespace(resolver, firstLine, isLineEmpty, previousLineBrokeCleanly);
+int w = 0;
+int tmpW = 0;
+if (resolver.position().atEnd())
+return resolver.position();
+// This variable is used only if whitespace isn't set to PRE, and it tells us whether
+// or not we are currently ignoring whitespace.
+bool ignoringSpaces = false;
+InlineIterator ignoreStart;
+// This variable tracks whether the very last character we saw was a space.  We use
+// this to detect when we encounter a second space so we know we have to terminate
+// a run.
+bool currentCharacterIsSpace = false;
+bool currentCharacterIsWS = false;
+RenderObject* trailingSpaceObject = 0;
+InlineIterator lBreak = resolver.position();
+RenderObject *o = resolver.position().obj;
+RenderObject *last = o;
+unsigned pos = resolver.position().pos;
+int nextBreakable = resolver.position().nextBreakablePosition;
+bool atStart = true;
+bool prevLineBrokeCleanly = previousLineBrokeCleanly;
+previousLineBrokeCleanly = false;
+hyphenated = false;
+bool autoWrapWasEverTrueOnLine = false;
+bool floatsFitOnLine = true;
+// Firefox and Opera will allow a table cell to grow to fit an image inside it under
+// very specific circumstances (in order to match common WinIE renderings).
+// Not supporting the quirk has caused us to mis-render some real sites. (See Bugzilla 10517.)
+bool allowImagesToBreak = !style()->htmlHacks() || !isTableCell() || !style()->width().isIntrinsicOrAuto();
+EWhiteSpace currWS = style()->whiteSpace();
+EWhiteSpace lastWS = currWS;
+while (o) {
+currWS = o->isReplaced() ? o->parent()->style()->whiteSpace() : o->style()->whiteSpace();
+lastWS = last->isReplaced() ? last->parent()->style()->whiteSpace() : last->style()->whiteSpace();
+bool autoWrap = RenderStyle::autoWrap(currWS);
+autoWrapWasEverTrueOnLine = autoWrapWasEverTrueOnLine || autoWrap;
+#if ENABLE(SVG)
+bool preserveNewline = o->isSVGInlineText() ? false : RenderStyle::preserveNewline(currWS);
+#else
+bool preserveNewline = RenderStyle::preserveNewline(currWS);
+#endif
+bool collapseWhiteSpace = RenderStyle::collapseWhiteSpace(currWS);
+if (o->isBR()) {
+if (w + tmpW <= width) {
+lBreak.obj = o;
+lBreak.pos = 0;
+lBreak.nextBreakablePosition = -1;
+lBreak.increment();
+// A <br> always breaks a line, so don't let the line be collapsed
+// away. Also, the space at the end of a line with a <br> does not
+// get collapsed away.  It only does this if the previous line broke
+// cleanly.  Otherwise the <br> has no effect on whether the line is
+// empty or not.
+if (prevLineBrokeCleanly)
+isLineEmpty = false;
+trailingSpaceObject = 0;
+previousLineBrokeCleanly = true;
+if (!isLineEmpty && clear)
+*clear = o->style()->clear();
+}
+goto end;
+}
+if (o->isFloatingOrPositioned()) {
+// add to special objects...
+if (o->isFloating()) {
+RenderBox* floatBox = toRenderBox(o);
+insertFloatingObject(floatBox);
+// check if it fits in the current line.
+// If it does, position it now, otherwise, position
+// it after moving to next line (in newLine() func)
+if (floatsFitOnLine && floatBox->width() + floatBox->marginLeft() + floatBox->marginRight() + w + tmpW <= width) {
+positionNewFloats();
+width = lineWidth(height(), firstLine);
+} else
+floatsFitOnLine = false;
+} else if (o->isPositioned()) {
+// If our original display wasn't an inline type, then we can
+// go ahead and determine our static x position now.
+RenderBox* box = toRenderBox(o);
+bool isInlineType = box->style()->isOriginalDisplayInlineType();
+bool needToSetStaticX = box->style()->hasStaticX();
+if (box->style()->hasStaticX() && !isInlineType) {
+box->layer()->setStaticX(o->parent()->style()->direction() == LTR ?
+borderLeft() + paddingLeft() :
+borderRight() + paddingRight());
+needToSetStaticX = false;
+}
+// If our original display was an INLINE type, then we can go ahead
+// and determine our static y position now.
+bool needToSetStaticY = box->style()->hasStaticY();
+if (box->style()->hasStaticY() && isInlineType) {
+box->layer()->setStaticY(height());
+needToSetStaticY = false;
+}
+bool needToCreateLineBox = needToSetStaticX || needToSetStaticY;
+RenderObject* c = o->container();
+if (c->isRenderInline() && (!needToSetStaticX || !needToSetStaticY))
+needToCreateLineBox = true;
+// If we're ignoring spaces, we have to stop and include this object and
+// then start ignoring spaces again.
+if (needToCreateLineBox) {
+trailingSpaceObject = 0;
+ignoreStart.obj = o;
+ignoreStart.pos = 0;
+if (ignoringSpaces) {
+addMidpoint(lineMidpointState, ignoreStart); // Stop ignoring spaces.
+addMidpoint(lineMidpointState, ignoreStart); // Start ignoring again.
+}
+}
+}
+} else if (o->isRenderInline()) {
+// Right now, we should only encounter empty inlines here.
+ASSERT(!o->firstChild());
+RenderInline* flowBox = toRenderInline(o);
+// Now that some inline flows have line boxes, if we are already ignoring spaces, we need
+// to make sure that we stop to include this object and then start ignoring spaces again.
+// If this object is at the start of the line, we need to behave like list markers and
+// start ignoring spaces.
+if (inlineFlowRequiresLineBox(flowBox)) {
+isLineEmpty = false;
+if (ignoringSpaces) {
+trailingSpaceObject = 0;
+addMidpoint(lineMidpointState, InlineIterator(0, o, 0)); // Stop ignoring spaces.
+addMidpoint(lineMidpointState, InlineIterator(0, o, 0)); // Start ignoring again.
+} else if (style()->collapseWhiteSpace() && resolver.position().obj == o
+&& shouldSkipWhitespaceAfterStartObject(this, o, lineMidpointState)) {
+// Like with list markers, we start ignoring spaces to make sure that any
+// additional spaces we see will be discarded.
+currentCharacterIsSpace = true;
+currentCharacterIsWS = true;
+ignoringSpaces = true;
+}
+}
+tmpW += flowBox->marginLeft() + flowBox->borderLeft() + flowBox->paddingLeft() +
+flowBox->marginRight() + flowBox->borderRight() + flowBox->paddingRight();
+} else if (o->isReplaced()) {
+RenderBox* replacedBox = toRenderBox(o);
+// Break on replaced elements if either has normal white-space.
+if ((autoWrap || RenderStyle::autoWrap(lastWS)) && (!o->isImage() || allowImagesToBreak)) {
+w += tmpW;
+tmpW = 0;
+lBreak.obj = o;
+lBreak.pos = 0;
+lBreak.nextBreakablePosition = -1;
+}
+if (ignoringSpaces)
+addMidpoint(lineMidpointState, InlineIterator(0, o, 0));
+isLineEmpty = false;
+ignoringSpaces = false;
+currentCharacterIsSpace = false;
+currentCharacterIsWS = false;
+trailingSpaceObject = 0;
+// Optimize for a common case. If we can't find whitespace after the list
+// item, then this is all moot. -dwh
+if (o->isListMarker()) {
+if (style()->collapseWhiteSpace() && shouldSkipWhitespaceAfterStartObject(this, o, lineMidpointState)) {
+// Like with inline flows, we start ignoring spaces to make sure that any
+// additional spaces we see will be discarded.
+currentCharacterIsSpace = true;
+currentCharacterIsWS = true;
+ignoringSpaces = true;
+}
+if (toRenderListMarker(o)->isInside())
+tmpW += replacedBox->width() + replacedBox->marginLeft() + replacedBox->marginRight() + inlineWidth(o);
+} else
+tmpW += replacedBox->width() + replacedBox->marginLeft() + replacedBox->marginRight() + inlineWidth(o);
+} else if (o->isText()) {
+if (!pos)
+appliedStartWidth = false;
+RenderText* t = toRenderText(o);
+int strlen = t->textLength();
+int len = strlen - pos;
+const UChar* str = t->characters();
+RenderStyle* style = t->style(firstLine);
+const Font& f = style->font();
+bool isFixedPitch = f.isFixedPitch();
+bool canHyphenate = style->hyphens() == HyphensAuto;
+int lastSpace = pos;
+int wordSpacing = o->style()->wordSpacing();
+int lastSpaceWordSpacing = 0;
+// Non-zero only when kerning is enabled, in which case we measure words with their trailing
+// space, then subtract its width.
+int wordTrailingSpaceWidth = f.typesettingFeatures() & Kerning ? f.width(TextRun(&space, 1)) + wordSpacing : 0;
+int wrapW = tmpW + inlineWidth(o, !appliedStartWidth, true);
+int charWidth = 0;
+bool breakNBSP = autoWrap && o->style()->nbspMode() == SPACE;
+// Auto-wrapping text should wrap in the middle of a word only if it could not wrap before the word,
+// which is only possible if the word is the first thing on the line, that is, if |w| is zero.
+bool breakWords = o->style()->breakWords() && ((autoWrap && !w) || currWS == PRE);
+bool midWordBreak = false;
+bool breakAll = o->style()->wordBreak() == BreakAllWordBreak && autoWrap;
+if (t->isWordBreak()) {
+w += tmpW;
+tmpW = 0;
+lBreak.obj = o;
+lBreak.pos = 0;
+lBreak.nextBreakablePosition = -1;
+ASSERT(!len);
+}
+while (len) {
+bool previousCharacterIsSpace = currentCharacterIsSpace;
+bool previousCharacterIsWS = currentCharacterIsWS;
+UChar c = str[pos];
+currentCharacterIsSpace = c == ' ' || c == '\t' || (!preserveNewline && (c == '\n'));
+if (!collapseWhiteSpace || !currentCharacterIsSpace)
+isLineEmpty = false;
+// Check for soft hyphens.  Go ahead and ignore them.
+if (c == softHyphen) {
+if (!ignoringSpaces) {
+// Ignore soft hyphens
+InlineIterator beforeSoftHyphen;
+if (pos)
+beforeSoftHyphen = InlineIterator(0, o, pos - 1);
+else
+beforeSoftHyphen = InlineIterator(0, last, last->isText() ? toRenderText(last)->textLength() - 1 : 0);
+// Two consecutive soft hyphens. Avoid overlapping midpoints.
+if (lineMidpointState.numMidpoints && lineMidpointState.midpoints[lineMidpointState.numMidpoints - 1].obj == o &&
+lineMidpointState.midpoints[lineMidpointState.numMidpoints - 1].pos == pos)
+lineMidpointState.numMidpoints--;
+else
+addMidpoint(lineMidpointState, beforeSoftHyphen);
+// Add the width up to but not including the hyphen.
+tmpW += textWidth(t, lastSpace, pos - lastSpace, f, w + tmpW, isFixedPitch, collapseWhiteSpace) + lastSpaceWordSpacing;
+// For wrapping text only, include the hyphen.  We need to ensure it will fit
+// on the line if it shows when we break.
+if (autoWrap)
+tmpW += textWidth(t, pos, 1, f, w + tmpW, isFixedPitch, collapseWhiteSpace);
+InlineIterator afterSoftHyphen(0, o, pos);
+afterSoftHyphen.increment();
+addMidpoint(lineMidpointState, afterSoftHyphen);
+}
+pos++;
+len--;
+lastSpaceWordSpacing = 0;
+lastSpace = pos; // Cheesy hack to prevent adding in widths of the run twice.
+if (style->hyphens() == HyphensNone) {
+// Prevent a line break at the soft hyphen by ensuring that betweenWords is false
+// in the next iteration.
+atStart = true;
+}
+continue;
+}
+bool applyWordSpacing = false;
+currentCharacterIsWS = currentCharacterIsSpace || (breakNBSP && c == noBreakSpace);
+if ((breakAll || breakWords) && !midWordBreak) {
+wrapW += charWidth;
+charWidth = textWidth(t, pos, 1, f, w + wrapW, isFixedPitch, collapseWhiteSpace);
+midWordBreak = w + wrapW + charWidth > width;
+}
+bool betweenWords = c == '\n' || (currWS != PRE && !atStart && isBreakable(str, pos, strlen, nextBreakable, breakNBSP));
+if (betweenWords || midWordBreak) {
+bool stoppedIgnoringSpaces = false;
+if (ignoringSpaces) {
+if (!currentCharacterIsSpace) {
+// Stop ignoring spaces and begin at this
+// new point.
+ignoringSpaces = false;
+lastSpaceWordSpacing = 0;
+lastSpace = pos; // e.g., "Foo    goo", don't add in any of the ignored spaces.
+addMidpoint(lineMidpointState, InlineIterator(0, o, pos));
+stoppedIgnoringSpaces = true;
+} else {
+// Just keep ignoring these spaces.
+pos++;
+len--;
+continue;
+}
+}
+int additionalTmpW;
+if (wordTrailingSpaceWidth && currentCharacterIsSpace)
+additionalTmpW = textWidth(t, lastSpace, pos + 1 - lastSpace, f, w + tmpW, isFixedPitch, collapseWhiteSpace) - wordTrailingSpaceWidth + lastSpaceWordSpacing;
+else
+additionalTmpW = textWidth(t, lastSpace, pos - lastSpace, f, w + tmpW, isFixedPitch, collapseWhiteSpace) + lastSpaceWordSpacing;
+tmpW += additionalTmpW;
+if (!appliedStartWidth) {
+tmpW += inlineWidth(o, true, false);
+appliedStartWidth = true;
+}
+applyWordSpacing =  wordSpacing && currentCharacterIsSpace && !previousCharacterIsSpace;
+if (!w && autoWrap && tmpW > width)
+fitBelowFloats(tmpW, firstLine, width);
+if (autoWrap || breakWords) {
+// If we break only after white-space, consider the current character
+// as candidate width for this line.
+bool lineWasTooWide = false;
+if (w + tmpW <= width && currentCharacterIsWS && o->style()->breakOnlyAfterWhiteSpace() && !midWordBreak) {
+int charWidth = textWidth(t, pos, 1, f, w + tmpW, isFixedPitch, collapseWhiteSpace) + (applyWordSpacing ? wordSpacing : 0);
+// Check if line is too big even without the extra space
+// at the end of the line. If it is not, do nothing.
+// If the line needs the extra whitespace to be too long,
+// then move the line break to the space and skip all
+// additional whitespace.
+if (w + tmpW + charWidth > width) {
+lineWasTooWide = true;
+lBreak.obj = o;
+lBreak.pos = pos;
+lBreak.nextBreakablePosition = nextBreakable;
+skipTrailingWhitespace(lBreak, isLineEmpty, previousLineBrokeCleanly);
+}
+}
+if (lineWasTooWide || w + tmpW > width) {
+if (canHyphenate && w + tmpW > width) {
+tryHyphenating(t, f, lastSpace, pos, w + tmpW - additionalTmpW, width, isFixedPitch, collapseWhiteSpace, lastSpaceWordSpacing, lBreak, nextBreakable, hyphenated);
+if (hyphenated)
+goto end;
+}
+if (lBreak.obj && shouldPreserveNewline(lBreak.obj) && lBreak.obj->isText() && toRenderText(lBreak.obj)->textLength() && !toRenderText(lBreak.obj)->isWordBreak() && toRenderText(lBreak.obj)->characters()[lBreak.pos] == '\n') {
+if (!stoppedIgnoringSpaces && pos > 0) {
+// We need to stop right before the newline and then start up again.
+addMidpoint(lineMidpointState, InlineIterator(0, o, pos - 1)); // Stop
+addMidpoint(lineMidpointState, InlineIterator(0, o, pos)); // Start
+}
+lBreak.increment();
+previousLineBrokeCleanly = true;
+}
+goto end; // Didn't fit. Jump to the end.
+} else {
+if (!betweenWords || (midWordBreak && !autoWrap))
+tmpW -= additionalTmpW;
+if (pos > 0 && str[pos-1] == softHyphen)
+// Subtract the width of the soft hyphen out since we fit on a line.
+tmpW -= textWidth(t, pos - 1, 1, f, w + tmpW, isFixedPitch, collapseWhiteSpace);
+}
+}
+if (c == '\n' && preserveNewline) {
+if (!stoppedIgnoringSpaces && pos > 0) {
+// We need to stop right before the newline and then start up again.
+addMidpoint(lineMidpointState, InlineIterator(0, o, pos - 1)); // Stop
+addMidpoint(lineMidpointState, InlineIterator(0, o, pos)); // Start
+}
+lBreak.obj = o;
+lBreak.pos = pos;
+lBreak.nextBreakablePosition = nextBreakable;
+lBreak.increment();
+previousLineBrokeCleanly = true;
+return lBreak;
+}
+if (autoWrap && betweenWords) {
+w += tmpW;
+wrapW = 0;
+tmpW = 0;
+lBreak.obj = o;
+lBreak.pos = pos;
+lBreak.nextBreakablePosition = nextBreakable;
+// Auto-wrapping text should not wrap in the middle of a word once it has had an
+// opportunity to break after a word.
+breakWords = false;
+}
+if (midWordBreak) {
+// Remember this as a breakable position in case
+// adding the end width forces a break.
+lBreak.obj = o;
+lBreak.pos = pos;
+lBreak.nextBreakablePosition = nextBreakable;
+midWordBreak &= (breakWords || breakAll);
+}
+if (betweenWords) {
+lastSpaceWordSpacing = applyWordSpacing ? wordSpacing : 0;
+lastSpace = pos;
+}
+if (!ignoringSpaces && o->style()->collapseWhiteSpace()) {
+// If we encounter a newline, or if we encounter a
+// second space, we need to go ahead and break up this
+// run and enter a mode where we start collapsing spaces.
+if (currentCharacterIsSpace && previousCharacterIsSpace) {
+ignoringSpaces = true;
+// We just entered a mode where we are ignoring
+// spaces. Create a midpoint to terminate the run
+// before the second space.
+addMidpoint(lineMidpointState, ignoreStart);
+}
+}
+} else if (ignoringSpaces) {
+// Stop ignoring spaces and begin at this
+// new point.
+ignoringSpaces = false;
+lastSpaceWordSpacing = applyWordSpacing ? wordSpacing : 0;
+lastSpace = pos; // e.g., "Foo    goo", don't add in any of the ignored spaces.
+addMidpoint(lineMidpointState, InlineIterator(0, o, pos));
+}
+if (currentCharacterIsSpace && !previousCharacterIsSpace) {
+ignoreStart.obj = o;
+ignoreStart.pos = pos;
+}
+if (!currentCharacterIsWS && previousCharacterIsWS) {
+if (autoWrap && o->style()->breakOnlyAfterWhiteSpace()) {
+lBreak.obj = o;
+lBreak.pos = pos;
+lBreak.nextBreakablePosition = nextBreakable;
+}
+}
+if (collapseWhiteSpace && currentCharacterIsSpace && !ignoringSpaces)
+trailingSpaceObject = o;
+else if (!o->style()->collapseWhiteSpace() || !currentCharacterIsSpace)
+trailingSpaceObject = 0;
+pos++;
+len--;
+atStart = false;
+}
+// IMPORTANT: pos is > length here!
+int additionalTmpW = ignoringSpaces ? 0 : textWidth(t, lastSpace, pos - lastSpace, f, w + tmpW, isFixedPitch, collapseWhiteSpace) + lastSpaceWordSpacing;
+tmpW += additionalTmpW;
+tmpW += inlineWidth(o, !appliedStartWidth, true);
+if (canHyphenate && w + tmpW > width) {
+tryHyphenating(t, f, lastSpace, pos, w + tmpW - additionalTmpW, width, isFixedPitch, collapseWhiteSpace, lastSpaceWordSpacing, lBreak, nextBreakable, hyphenated);
+if (hyphenated)
+goto end;
+}
+} else
+ASSERT_NOT_REACHED();
+RenderObject* next = bidiNext(this, o);
+bool checkForBreak = autoWrap;
+if (w && w + tmpW > width && lBreak.obj && currWS == NOWRAP)
+checkForBreak = true;
+else if (next && o->isText() && next->isText() && !next->isBR()) {
+if (autoWrap || (next->style()->autoWrap())) {
+if (currentCharacterIsSpace)
+checkForBreak = true;
+else {
+checkForBreak = false;
+RenderText* nextText = toRenderText(next);
+if (nextText->textLength()) {
+UChar c = nextText->characters()[0];
+if (c == ' ' || c == '\t' || (c == '\n' && !shouldPreserveNewline(next)))
+// If the next item on the line is text, and if we did not end with
+// a space, then the next text run continues our word (and so it needs to
+// keep adding to |tmpW|.  Just update and continue.
+checkForBreak = true;
+} else if (nextText->isWordBreak())
+checkForBreak = true;
+bool willFitOnLine = w + tmpW <= width;
+if (!willFitOnLine && !w) {
+fitBelowFloats(tmpW, firstLine, width);
+willFitOnLine = tmpW <= width;
+}
+bool canPlaceOnLine = willFitOnLine || !autoWrapWasEverTrueOnLine;
+if (canPlaceOnLine && checkForBreak) {
+w += tmpW;
+tmpW = 0;
+lBreak.obj = next;
+lBreak.pos = 0;
+lBreak.nextBreakablePosition = -1;
+}
+}
+}
+}
+if (checkForBreak && (w + tmpW > width)) {
+// if we have floats, try to get below them.
+if (currentCharacterIsSpace && !ignoringSpaces && o->style()->collapseWhiteSpace())
+trailingSpaceObject = 0;
+if (w)
+goto end;
+fitBelowFloats(tmpW, firstLine, width);
+// |width| may have been adjusted because we got shoved down past a float (thus
+// giving us more room), so we need to retest, and only jump to
+// the end label if we still don't fit on the line. -dwh
+if (w + tmpW > width)
+goto end;
+}
+if (!o->isFloatingOrPositioned()) {
+last = o;
+if (last->isReplaced() && autoWrap && (!last->isImage() || allowImagesToBreak) && (!last->isListMarker() || toRenderListMarker(last)->isInside())) {
+w += tmpW;
+tmpW = 0;
+lBreak.obj = next;
+lBreak.pos = 0;
+lBreak.nextBreakablePosition = -1;
+}
+}
+o = next;
+nextBreakable = -1;
+// Clear out our character space bool, since inline <pre>s don't collapse whitespace
+// with adjacent inline normal/nowrap spans.
+if (!collapseWhiteSpace)
+currentCharacterIsSpace = false;
+pos = 0;
+atStart = false;
+}
+if (w + tmpW <= width || lastWS == NOWRAP) {
+lBreak.obj = 0;
+lBreak.pos = 0;
+lBreak.nextBreakablePosition = -1;
+}
+end:
+if (lBreak == resolver.position() && (!lBreak.obj || !lBreak.obj->isBR())) {
+// we just add as much as possible
+if (style()->whiteSpace() == PRE) {
+// FIXME: Don't really understand this case.
+if (pos != 0) {
+lBreak.obj = o;
+lBreak.pos = pos - 1;
+} else {
+lBreak.obj = last;
+lBreak.pos = last->isText() ? last->length() : 0;
+lBreak.nextBreakablePosition = -1;
+}
+} else if (lBreak.obj) {
+// Don't ever break in the middle of a word if we can help it.
+// There's no room at all. We just have to be on this line,
+// even though we'll spill out.
+lBreak.obj = o;
+lBreak.pos = pos;
+lBreak.nextBreakablePosition = -1;
+}
+}
+// make sure we consume at least one char/object.
+if (lBreak == resolver.position())
+lBreak.increment();
+// Sanity check our midpoints.
+checkMidpoints(lineMidpointState, lBreak);
+if (trailingSpaceObject) {
+// This object is either going to be part of the last midpoint, or it is going
+// to be the actual endpoint.  In both cases we just decrease our pos by 1 level to
+// exclude the space, allowing it to - in effect - collapse into the newline.
+if (lineMidpointState.numMidpoints % 2) {
+InlineIterator* midpoints = lineMidpointState.midpoints.data();
+midpoints[lineMidpointState.numMidpoints - 1].pos--;
+}
+//else if (lBreak.pos > 0)
+//    lBreak.pos--;
+else if (lBreak.obj == 0 && trailingSpaceObject->isText()) {
+// Add a new end midpoint that stops right at the very end.
+RenderText* text = toRenderText(trailingSpaceObject);
+unsigned length = text->textLength();
+unsigned pos = length >= 2 ? length - 2 : UINT_MAX;
+InlineIterator endMid(0, trailingSpaceObject, pos);
+addMidpoint(lineMidpointState, endMid);
+}
+}
+// We might have made lBreak an iterator that points past the end
+// of the object. Do this adjustment to make it point to the start
+// of the next object instead to avoid confusing the rest of the
+// code.
+if (lBreak.pos > 0) {
+lBreak.pos--;
+lBreak.increment();
+}
+if (lBreak.obj && lBreak.pos >= 2 && lBreak.obj->isText()) {
+// For soft hyphens on line breaks, we have to chop out the midpoints that made us
+// ignore the hyphen so that it will render at the end of the line.
+UChar c = toRenderText(lBreak.obj)->characters()[lBreak.pos - 1];
+if (c == softHyphen)
+chopMidpointsAt(lineMidpointState, lBreak.obj, lBreak.pos - 2);
+}
+return lBreak;
+}
+void RenderBlock::addOverflowFromInlineChildren()
+{
+for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
+addLayoutOverflow(curr->layoutOverflowRect());
+if (!hasOverflowClip())
+addVisualOverflow(curr->visualOverflowRect());
+}
+}
+void RenderBlock::deleteEllipsisLineBoxes()
+{
+for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox())
+curr->clearTruncation();
+}
+void RenderBlock::checkLinesForTextOverflow()
+{
+// Determine the width of the ellipsis using the current font.
+// FIXME: CSS3 says this is configurable, also need to use 0x002E (FULL STOP) if horizontal ellipsis is "not renderable"
+TextRun ellipsisRun(&horizontalEllipsis, 1);
+DEFINE_STATIC_LOCAL(AtomicString, ellipsisStr, (&horizontalEllipsis, 1));
+const Font& firstLineFont = firstLineStyle()->font();
+const Font& font = style()->font();
+int firstLineEllipsisWidth = firstLineFont.width(ellipsisRun);
+int ellipsisWidth = (font == firstLineFont) ? firstLineEllipsisWidth : font.width(ellipsisRun);
+// For LTR text truncation, we want to get the right edge of our padding box, and then we want to see
+// if the right edge of a line box exceeds that.  For RTL, we use the left edge of the padding box and
+// check the left edge of the line box to see if it is less
+// Include the scrollbar for overflow blocks, which means we want to use "contentWidth()"
+bool ltr = style()->direction() == LTR;
+for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
+int blockRightEdge = rightOffset(curr->y(), curr == firstRootBox());
+int blockLeftEdge = leftOffset(curr->y(), curr == firstRootBox());
+int lineBoxEdge = ltr ? curr->x() + curr->width() : curr->x();
+if ((ltr && lineBoxEdge > blockRightEdge) || (!ltr && lineBoxEdge < blockLeftEdge)) {
+// This line spills out of our box in the appropriate direction.  Now we need to see if the line
+// can be truncated.  In order for truncation to be possible, the line must have sufficient space to
+// accommodate our truncation string, and no replaced elements (images, tables) can overlap the ellipsis
+// space.
+int width = curr == firstRootBox() ? firstLineEllipsisWidth : ellipsisWidth;
+int blockEdge = ltr ? blockRightEdge : blockLeftEdge;
+if (curr->canAccommodateEllipsis(ltr, blockEdge, lineBoxEdge, width))
+curr->placeEllipsis(ellipsisStr, ltr, blockLeftEdge, blockRightEdge, width);
+}
+}
+}
+}