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32 #include "core/rendering/RenderBlockFlow.h"
34 #include "core/accessibility/AXObjectCache.h"
35 #include "core/frame/FrameView.h"
36 #include "core/rendering/FastTextAutosizer.h"
37 #include "core/rendering/HitTestLocation.h"
38 #include "core/rendering/LayoutRepainter.h"
39 #include "core/rendering/RenderFlowThread.h"
40 #include "core/rendering/RenderLayer.h"
41 #include "core/rendering/RenderMultiColumnFlowThread.h"
42 #include "core/rendering/RenderText.h"
43 #include "core/rendering/RenderView.h"
44 #include "core/rendering/line/LineWidth.h"
45 #include "core/rendering/svg/SVGTextRunRenderingContext.h"
46 #include "platform/text/BidiTextRun.h"
52 bool RenderBlockFlow::s_canPropagateFloatIntoSibling = false;
54 struct SameSizeAsMarginInfo {
56 LayoutUnit margins[2];
59 COMPILE_ASSERT(sizeof(RenderBlockFlow::MarginValues) == sizeof(LayoutUnit[4]), MarginValues_should_stay_small);
62 // Collapsing flags for whether we can collapse our margins with our children's margins.
63 bool m_canCollapseWithChildren : 1;
64 bool m_canCollapseMarginBeforeWithChildren : 1;
65 bool m_canCollapseMarginAfterWithChildren : 1;
66 bool m_canCollapseMarginAfterWithLastChild: 1;
68 // Whether or not we are a quirky container, i.e., do we collapse away top and bottom
69 // margins in our container. Table cells and the body are the common examples. We
70 // also have a custom style property for Safari RSS to deal with TypePad blog articles.
71 bool m_quirkContainer : 1;
73 // This flag tracks whether we are still looking at child margins that can all collapse together at the beginning of a block.
74 // They may or may not collapse with the top margin of the block (|m_canCollapseTopWithChildren| tells us that), but they will
75 // always be collapsing with one another. This variable can remain set to true through multiple iterations
76 // as long as we keep encountering self-collapsing blocks.
77 bool m_atBeforeSideOfBlock : 1;
79 // This flag is set when we know we're examining bottom margins and we know we're at the bottom of the block.
80 bool m_atAfterSideOfBlock : 1;
82 // These variables are used to detect quirky margins that we need to collapse away (in table cells
83 // and in the body element).
84 bool m_hasMarginBeforeQuirk : 1;
85 bool m_hasMarginAfterQuirk : 1;
86 bool m_determinedMarginBeforeQuirk : 1;
88 bool m_discardMargin : 1;
90 // These flags track the previous maximal positive and negative margins.
91 LayoutUnit m_positiveMargin;
92 LayoutUnit m_negativeMargin;
95 MarginInfo(RenderBlockFlow*, LayoutUnit beforeBorderPadding, LayoutUnit afterBorderPadding);
97 void setAtBeforeSideOfBlock(bool b) { m_atBeforeSideOfBlock = b; }
98 void setAtAfterSideOfBlock(bool b) { m_atAfterSideOfBlock = b; }
101 m_positiveMargin = 0;
102 m_negativeMargin = 0;
104 void setHasMarginBeforeQuirk(bool b) { m_hasMarginBeforeQuirk = b; }
105 void setHasMarginAfterQuirk(bool b) { m_hasMarginAfterQuirk = b; }
106 void setDeterminedMarginBeforeQuirk(bool b) { m_determinedMarginBeforeQuirk = b; }
107 void setPositiveMargin(LayoutUnit p) { ASSERT(!m_discardMargin); m_positiveMargin = p; }
108 void setNegativeMargin(LayoutUnit n) { ASSERT(!m_discardMargin); m_negativeMargin = n; }
109 void setPositiveMarginIfLarger(LayoutUnit p)
111 ASSERT(!m_discardMargin);
112 if (p > m_positiveMargin)
113 m_positiveMargin = p;
115 void setNegativeMarginIfLarger(LayoutUnit n)
117 ASSERT(!m_discardMargin);
118 if (n > m_negativeMargin)
119 m_negativeMargin = n;
122 void setMargin(LayoutUnit p, LayoutUnit n) { ASSERT(!m_discardMargin); m_positiveMargin = p; m_negativeMargin = n; }
123 void setCanCollapseMarginAfterWithChildren(bool collapse) { m_canCollapseMarginAfterWithChildren = collapse; }
124 void setCanCollapseMarginAfterWithLastChild(bool collapse) { m_canCollapseMarginAfterWithLastChild = collapse; }
125 void setDiscardMargin(bool value) { m_discardMargin = value; }
127 bool atBeforeSideOfBlock() const { return m_atBeforeSideOfBlock; }
128 bool canCollapseWithMarginBefore() const { return m_atBeforeSideOfBlock && m_canCollapseMarginBeforeWithChildren; }
129 bool canCollapseWithMarginAfter() const { return m_atAfterSideOfBlock && m_canCollapseMarginAfterWithChildren; }
130 bool canCollapseMarginBeforeWithChildren() const { return m_canCollapseMarginBeforeWithChildren; }
131 bool canCollapseMarginAfterWithChildren() const { return m_canCollapseMarginAfterWithChildren; }
132 bool canCollapseMarginAfterWithLastChild() const { return m_canCollapseMarginAfterWithLastChild; }
133 bool quirkContainer() const { return m_quirkContainer; }
134 bool determinedMarginBeforeQuirk() const { return m_determinedMarginBeforeQuirk; }
135 bool hasMarginBeforeQuirk() const { return m_hasMarginBeforeQuirk; }
136 bool hasMarginAfterQuirk() const { return m_hasMarginAfterQuirk; }
137 LayoutUnit positiveMargin() const { return m_positiveMargin; }
138 LayoutUnit negativeMargin() const { return m_negativeMargin; }
139 bool discardMargin() const { return m_discardMargin; }
140 LayoutUnit margin() const { return m_positiveMargin - m_negativeMargin; }
142 static bool inNormalFlow(RenderBox* child)
144 RenderBlock* curr = child->containingBlock();
145 RenderView* renderView = child->view();
146 while (curr && curr != renderView) {
147 if (curr->hasColumns() || curr->isRenderFlowThread())
149 if (curr->isFloatingOrOutOfFlowPositioned())
151 curr = curr->containingBlock();
156 RenderBlockFlow::RenderBlockFlow(ContainerNode* node)
159 COMPILE_ASSERT(sizeof(MarginInfo) == sizeof(SameSizeAsMarginInfo), MarginInfo_should_stay_small);
162 RenderBlockFlow::~RenderBlockFlow()
166 RenderBlockFlow* RenderBlockFlow::createAnonymous(Document* document)
168 RenderBlockFlow* renderer = new RenderBlockFlow(0);
169 renderer->setDocumentForAnonymous(document);
173 RenderObject* RenderBlockFlow::layoutSpecialExcludedChild(bool relayoutChildren, SubtreeLayoutScope& layoutScope)
175 RenderMultiColumnFlowThread* flowThread = multiColumnFlowThread();
178 setLogicalTopForChild(flowThread, borderBefore() + paddingBefore());
179 flowThread->layoutColumns(relayoutChildren, layoutScope);
180 determineLogicalLeftPositionForChild(flowThread);
184 bool RenderBlockFlow::updateLogicalWidthAndColumnWidth()
186 bool relayoutChildren = RenderBlock::updateLogicalWidthAndColumnWidth();
187 if (RenderMultiColumnFlowThread* flowThread = multiColumnFlowThread()) {
188 if (flowThread->needsNewWidth())
191 return relayoutChildren;
194 void RenderBlockFlow::checkForPaginationLogicalHeightChange(LayoutUnit& pageLogicalHeight, bool& pageLogicalHeightChanged, bool& hasSpecifiedPageLogicalHeight)
196 if (RenderMultiColumnFlowThread* flowThread = multiColumnFlowThread()) {
197 LogicalExtentComputedValues computedValues;
198 computeLogicalHeight(LayoutUnit(), logicalTop(), computedValues);
199 LayoutUnit columnHeight = computedValues.m_extent - borderAndPaddingLogicalHeight() - scrollbarLogicalHeight();
200 pageLogicalHeightChanged = columnHeight != flowThread->columnHeightAvailable();
201 flowThread->setColumnHeightAvailable(std::max<LayoutUnit>(columnHeight, 0));
202 } else if (hasColumns()) {
203 ColumnInfo* colInfo = columnInfo();
205 if (!pageLogicalHeight) {
206 LayoutUnit oldLogicalHeight = logicalHeight();
208 // We need to go ahead and set our explicit page height if one exists, so that we can
209 // avoid doing two layout passes.
210 updateLogicalHeight();
211 LayoutUnit columnHeight = contentLogicalHeight();
212 if (columnHeight > 0) {
213 pageLogicalHeight = columnHeight;
214 hasSpecifiedPageLogicalHeight = true;
216 setLogicalHeight(oldLogicalHeight);
218 if (colInfo->columnHeight() != pageLogicalHeight && everHadLayout()) {
219 colInfo->setColumnHeight(pageLogicalHeight);
220 pageLogicalHeightChanged = true;
223 if (!hasSpecifiedPageLogicalHeight && !pageLogicalHeight)
224 colInfo->clearForcedBreaks();
225 } else if (isRenderFlowThread()) {
226 RenderFlowThread* flowThread = toRenderFlowThread(this);
228 // FIXME: This is a hack to always make sure we have a page logical height, if said height
229 // is known. The page logical height thing in LayoutState is meaningless for flow
230 // thread-based pagination (page height isn't necessarily uniform throughout the flow
231 // thread), but as long as it is used universally as a means to determine whether page
232 // height is known or not, we need this. Page height is unknown when column balancing is
233 // enabled and flow thread height is still unknown (i.e. during the first layout pass). When
234 // it's unknown, we need to prevent the pagination code from assuming page breaks everywhere
235 // and thereby eating every top margin. It should be trivial to clean up and get rid of this
236 // hack once the old multicol implementation is gone.
237 pageLogicalHeight = flowThread->isPageLogicalHeightKnown() ? LayoutUnit(1) : LayoutUnit(0);
239 pageLogicalHeightChanged = flowThread->pageLogicalSizeChanged();
243 bool RenderBlockFlow::shouldRelayoutForPagination(LayoutUnit& pageLogicalHeight, LayoutUnit layoutOverflowLogicalBottom) const
245 // FIXME: We don't balance properly at all in the presence of forced page breaks. We need to understand what
246 // the distance between forced page breaks is so that we can avoid making the minimum column height too tall.
247 ColumnInfo* colInfo = columnInfo();
248 LayoutUnit columnHeight = pageLogicalHeight;
249 const int minColumnCount = colInfo->forcedBreaks() + 1;
250 const int desiredColumnCount = colInfo->desiredColumnCount();
251 if (minColumnCount >= desiredColumnCount) {
252 // The forced page breaks are in control of the balancing. Just set the column height to the
253 // maximum page break distance.
254 if (!pageLogicalHeight) {
255 LayoutUnit distanceBetweenBreaks = max<LayoutUnit>(colInfo->maximumDistanceBetweenForcedBreaks(),
256 view()->layoutState()->pageLogicalOffset(*this, borderBefore() + paddingBefore() + layoutOverflowLogicalBottom) - colInfo->forcedBreakOffset());
257 columnHeight = max(colInfo->minimumColumnHeight(), distanceBetweenBreaks);
259 } else if (layoutOverflowLogicalBottom > boundedMultiply(pageLogicalHeight, desiredColumnCount)) {
260 // Now that we know the intrinsic height of the columns, we have to rebalance them.
261 columnHeight = max<LayoutUnit>(colInfo->minimumColumnHeight(), ceilf(layoutOverflowLogicalBottom.toFloat() / desiredColumnCount));
264 if (columnHeight && columnHeight != pageLogicalHeight) {
265 pageLogicalHeight = columnHeight;
272 void RenderBlockFlow::setColumnCountAndHeight(unsigned count, LayoutUnit pageLogicalHeight)
274 ColumnInfo* colInfo = columnInfo();
275 if (pageLogicalHeight)
276 colInfo->setColumnCountAndHeight(count, pageLogicalHeight);
278 if (columnCount(colInfo)) {
279 setLogicalHeight(borderBefore() + paddingBefore() + colInfo->columnHeight() + borderAfter() + paddingAfter() + scrollbarLogicalHeight());
284 bool RenderBlockFlow::isSelfCollapsingBlock() const
286 m_hasOnlySelfCollapsingChildren = RenderBlock::isSelfCollapsingBlock();
287 return m_hasOnlySelfCollapsingChildren;
290 void RenderBlockFlow::layoutBlock(bool relayoutChildren)
292 ASSERT(needsLayout());
293 ASSERT(isInlineBlockOrInlineTable() || !isInline());
295 // If we are self-collapsing with self-collapsing descendants this will get set to save us burrowing through our
296 // descendants every time in |isSelfCollapsingBlock|. We reset it here so that |isSelfCollapsingBlock| attempts to burrow
297 // at least once and so that it always gives a reliable result reflecting the latest layout.
298 m_hasOnlySelfCollapsingChildren = false;
300 if (!relayoutChildren && simplifiedLayout())
303 SubtreeLayoutScope layoutScope(*this);
305 // Multiple passes might be required for column and pagination based layout
306 // In the case of the old column code the number of passes will only be two
307 // however, in the newer column code the number of passes could equal the
308 // number of columns.
310 LayoutUnit pageLogicalHeight = 0;
311 LayoutRepainter repainter(*this, checkForPaintInvalidationDuringLayout());
313 done = layoutBlockFlow(relayoutChildren, pageLogicalHeight, layoutScope);
315 fitBorderToLinesIfNeeded();
317 RenderView* renderView = view();
318 if (renderView->layoutState()->pageLogicalHeight())
319 setPageLogicalOffset(renderView->layoutState()->pageLogicalOffset(*this, logicalTop()));
321 updateLayerTransformAfterLayout();
323 // Update our scroll information if we're overflow:auto/scroll/hidden now that we know if
324 // we overflow or not.
325 updateScrollInfoAfterLayout();
327 // Repaint with our new bounds if they are different from our old bounds.
328 bool didFullRepaint = repainter.repaintAfterLayout();
329 if (!didFullRepaint && m_repaintLogicalTop != m_repaintLogicalBottom && (style()->visibility() == VISIBLE || enclosingLayer()->hasVisibleContent())) {
330 if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
331 setShouldInvalidateOverflowForPaint(true);
333 invalidatePaintForOverflow();
338 inline bool RenderBlockFlow::layoutBlockFlow(bool relayoutChildren, LayoutUnit &pageLogicalHeight, SubtreeLayoutScope& layoutScope)
340 LayoutUnit oldLeft = logicalLeft();
341 if (updateLogicalWidthAndColumnWidth())
342 relayoutChildren = true;
344 rebuildFloatsFromIntruding();
346 bool pageLogicalHeightChanged = false;
347 bool hasSpecifiedPageLogicalHeight = false;
348 checkForPaginationLogicalHeightChange(pageLogicalHeight, pageLogicalHeightChanged, hasSpecifiedPageLogicalHeight);
349 if (pageLogicalHeightChanged)
350 relayoutChildren = true;
352 LayoutState state(*this, locationOffset(), pageLogicalHeight, pageLogicalHeightChanged, columnInfo());
354 // We use four values, maxTopPos, maxTopNeg, maxBottomPos, and maxBottomNeg, to track
355 // our current maximal positive and negative margins. These values are used when we
356 // are collapsed with adjacent blocks, so for example, if you have block A and B
357 // collapsing together, then you'd take the maximal positive margin from both A and B
358 // and subtract it from the maximal negative margin from both A and B to get the
359 // true collapsed margin. This algorithm is recursive, so when we finish layout()
360 // our block knows its current maximal positive/negative values.
362 // Start out by setting our margin values to our current margins. Table cells have
363 // no margins, so we don't fill in the values for table cells.
364 if (!isTableCell()) {
365 initMaxMarginValues();
366 setHasMarginBeforeQuirk(style()->hasMarginBeforeQuirk());
367 setHasMarginAfterQuirk(style()->hasMarginAfterQuirk());
368 setPaginationStrut(0);
371 LayoutUnit beforeEdge = borderBefore() + paddingBefore();
372 LayoutUnit afterEdge = borderAfter() + paddingAfter() + scrollbarLogicalHeight();
373 LayoutUnit previousHeight = logicalHeight();
374 setLogicalHeight(beforeEdge);
376 m_repaintLogicalTop = 0;
377 m_repaintLogicalBottom = 0;
378 if (!firstChild() && !isAnonymousBlock())
379 setChildrenInline(true);
381 FastTextAutosizer::LayoutScope fastTextAutosizerLayoutScope(this);
383 if (childrenInline())
384 layoutInlineChildren(relayoutChildren, m_repaintLogicalTop, m_repaintLogicalBottom, afterEdge);
386 layoutBlockChildren(relayoutChildren, layoutScope, beforeEdge, afterEdge);
388 // Expand our intrinsic height to encompass floats.
389 if (lowestFloatLogicalBottom() > (logicalHeight() - afterEdge) && createsBlockFormattingContext())
390 setLogicalHeight(lowestFloatLogicalBottom() + afterEdge);
392 if (RenderMultiColumnFlowThread* flowThread = multiColumnFlowThread()) {
393 if (flowThread->recalculateColumnHeights()) {
394 setChildNeedsLayout(MarkOnlyThis);
397 } else if (hasColumns()) {
398 OwnPtr<RenderOverflow> savedOverflow = m_overflow.release();
399 if (childrenInline())
400 addOverflowFromInlineChildren();
402 addOverflowFromBlockChildren();
403 LayoutUnit layoutOverflowLogicalBottom = (isHorizontalWritingMode() ? layoutOverflowRect().maxY() : layoutOverflowRect().maxX()) - borderBefore() - paddingBefore();
404 m_overflow = savedOverflow.release();
406 if (!hasSpecifiedPageLogicalHeight && shouldRelayoutForPagination(pageLogicalHeight, layoutOverflowLogicalBottom)) {
407 setEverHadLayout(true);
411 setColumnCountAndHeight(ceilf(layoutOverflowLogicalBottom.toFloat() / pageLogicalHeight.toFloat()), pageLogicalHeight.toFloat());
414 if (shouldBreakAtLineToAvoidWidow()) {
415 setEverHadLayout(true);
419 // Calculate our new height.
420 LayoutUnit oldHeight = logicalHeight();
421 LayoutUnit oldClientAfterEdge = clientLogicalBottom();
423 updateLogicalHeight();
424 LayoutUnit newHeight = logicalHeight();
425 if (oldHeight > newHeight && !childrenInline()) {
426 // One of our children's floats may have become an overhanging float for us.
427 for (RenderObject* child = lastChild(); child; child = child->previousSibling()) {
428 if (child->isRenderBlockFlow() && !child->isFloatingOrOutOfFlowPositioned()) {
429 RenderBlockFlow* block = toRenderBlockFlow(child);
430 if (block->lowestFloatLogicalBottom() + block->logicalTop() <= newHeight)
432 addOverhangingFloats(block, false);
437 bool heightChanged = (previousHeight != newHeight);
439 relayoutChildren = true;
441 layoutPositionedObjects(relayoutChildren || isDocumentElement(), oldLeft != logicalLeft() ? ForcedLayoutAfterContainingBlockMoved : DefaultLayout);
443 computeRegionRangeForBlock(flowThreadContainingBlock());
445 // Add overflow from children (unless we're multi-column, since in that case all our child overflow is clipped anyway).
446 computeOverflow(oldClientAfterEdge);
451 void RenderBlockFlow::determineLogicalLeftPositionForChild(RenderBox* child, ApplyLayoutDeltaMode applyDelta)
453 LayoutUnit startPosition = borderStart() + paddingStart();
454 if (style()->shouldPlaceBlockDirectionScrollbarOnLogicalLeft())
455 startPosition -= verticalScrollbarWidth();
456 LayoutUnit totalAvailableLogicalWidth = borderAndPaddingLogicalWidth() + availableLogicalWidth();
458 // Add in our start margin.
459 LayoutUnit childMarginStart = marginStartForChild(child);
460 LayoutUnit newPosition = startPosition + childMarginStart;
462 // Some objects (e.g., tables, horizontal rules, overflow:auto blocks) avoid floats. They need
463 // to shift over as necessary to dodge any floats that might get in the way.
464 if (child->avoidsFloats() && containsFloats() && !flowThreadContainingBlock())
465 newPosition += computeStartPositionDeltaForChildAvoidingFloats(child, marginStartForChild(child));
467 setLogicalLeftForChild(child, style()->isLeftToRightDirection() ? newPosition : totalAvailableLogicalWidth - newPosition - logicalWidthForChild(child), applyDelta);
470 void RenderBlockFlow::setLogicalLeftForChild(RenderBox* child, LayoutUnit logicalLeft, ApplyLayoutDeltaMode applyDelta)
472 if (isHorizontalWritingMode()) {
473 if (applyDelta == ApplyLayoutDelta && !RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
474 view()->addLayoutDelta(LayoutSize(child->x() - logicalLeft, 0));
475 child->setX(logicalLeft);
477 if (applyDelta == ApplyLayoutDelta && !RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
478 view()->addLayoutDelta(LayoutSize(0, child->y() - logicalLeft));
479 child->setY(logicalLeft);
483 void RenderBlockFlow::setLogicalTopForChild(RenderBox* child, LayoutUnit logicalTop, ApplyLayoutDeltaMode applyDelta)
485 if (isHorizontalWritingMode()) {
486 if (applyDelta == ApplyLayoutDelta && !RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
487 view()->addLayoutDelta(LayoutSize(0, child->y() - logicalTop));
488 child->setY(logicalTop);
490 if (applyDelta == ApplyLayoutDelta && !RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
491 view()->addLayoutDelta(LayoutSize(child->x() - logicalTop, 0));
492 child->setX(logicalTop);
496 void RenderBlockFlow::layoutBlockChild(RenderBox* child, MarginInfo& marginInfo, LayoutUnit& previousFloatLogicalBottom)
498 LayoutUnit oldPosMarginBefore = maxPositiveMarginBefore();
499 LayoutUnit oldNegMarginBefore = maxNegativeMarginBefore();
501 // The child is a normal flow object. Compute the margins we will use for collapsing now.
502 child->computeAndSetBlockDirectionMargins(this);
504 // Try to guess our correct logical top position. In most cases this guess will
505 // be correct. Only if we're wrong (when we compute the real logical top position)
506 // will we have to potentially relayout.
507 LayoutUnit estimateWithoutPagination;
508 LayoutUnit logicalTopEstimate = estimateLogicalTopPosition(child, marginInfo, estimateWithoutPagination);
510 // Cache our old rect so that we can dirty the proper repaint rects if the child moves.
511 LayoutRect oldRect = child->frameRect();
512 LayoutUnit oldLogicalTop = logicalTopForChild(child);
515 LayoutSize oldLayoutDelta = RuntimeEnabledFeatures::repaintAfterLayoutEnabled() ? LayoutSize() : view()->layoutDelta();
517 // Go ahead and position the child as though it didn't collapse with the top.
518 setLogicalTopForChild(child, logicalTopEstimate, ApplyLayoutDelta);
520 RenderBlock* childRenderBlock = child->isRenderBlock() ? toRenderBlock(child) : 0;
521 RenderBlockFlow* childRenderBlockFlow = (childRenderBlock && child->isRenderBlockFlow()) ? toRenderBlockFlow(child) : 0;
522 bool markDescendantsWithFloats = false;
523 if (logicalTopEstimate != oldLogicalTop && !child->avoidsFloats() && childRenderBlock && childRenderBlock->containsFloats()) {
524 markDescendantsWithFloats = true;
525 } else if (UNLIKELY(logicalTopEstimate.mightBeSaturated())) {
526 // logicalTopEstimate, returned by estimateLogicalTopPosition, might be saturated for
527 // very large elements. If it does the comparison with oldLogicalTop might yield a
528 // false negative as adding and removing margins, borders etc from a saturated number
529 // might yield incorrect results. If this is the case always mark for layout.
530 markDescendantsWithFloats = true;
531 } else if (!child->avoidsFloats() || child->shrinkToAvoidFloats()) {
532 // If an element might be affected by the presence of floats, then always mark it for
534 LayoutUnit fb = max(previousFloatLogicalBottom, lowestFloatLogicalBottom());
535 if (fb > logicalTopEstimate)
536 markDescendantsWithFloats = true;
539 if (childRenderBlockFlow) {
540 if (markDescendantsWithFloats)
541 childRenderBlockFlow->markAllDescendantsWithFloatsForLayout();
542 if (!child->isWritingModeRoot())
543 previousFloatLogicalBottom = max(previousFloatLogicalBottom, oldLogicalTop + childRenderBlockFlow->lowestFloatLogicalBottom());
546 SubtreeLayoutScope layoutScope(*child);
547 if (!child->needsLayout())
548 child->markForPaginationRelayoutIfNeeded(layoutScope);
550 bool childHadLayout = child->everHadLayout();
551 bool childNeededLayout = child->needsLayout();
552 if (childNeededLayout)
555 // Cache if we are at the top of the block right now.
556 bool atBeforeSideOfBlock = marginInfo.atBeforeSideOfBlock();
557 bool childIsSelfCollapsing = child->isSelfCollapsingBlock();
559 // Now determine the correct ypos based off examination of collapsing margin
561 LayoutUnit logicalTopBeforeClear = collapseMargins(child, marginInfo, childIsSelfCollapsing);
563 // Now check for clear.
564 LayoutUnit logicalTopAfterClear = clearFloatsIfNeeded(child, marginInfo, oldPosMarginBefore, oldNegMarginBefore, logicalTopBeforeClear, childIsSelfCollapsing);
566 bool paginated = view()->layoutState()->isPaginated();
568 logicalTopAfterClear = adjustBlockChildForPagination(logicalTopAfterClear, estimateWithoutPagination, child,
569 atBeforeSideOfBlock && logicalTopBeforeClear == logicalTopAfterClear);
572 setLogicalTopForChild(child, logicalTopAfterClear, ApplyLayoutDelta);
574 // Now we have a final top position. See if it really does end up being different from our estimate.
575 // clearFloatsIfNeeded can also mark the child as needing a layout even though we didn't move. This happens
576 // when collapseMargins dynamically adds overhanging floats because of a child with negative margins.
577 if (logicalTopAfterClear != logicalTopEstimate || child->needsLayout() || (paginated && childRenderBlock && childRenderBlock->shouldBreakAtLineToAvoidWidow())) {
578 SubtreeLayoutScope layoutScope(*child);
579 if (child->shrinkToAvoidFloats()) {
580 // The child's width depends on the line width.
581 // When the child shifts to clear an item, its width can
582 // change (because it has more available line width).
583 // So go ahead and mark the item as dirty.
584 layoutScope.setChildNeedsLayout(child);
587 if (childRenderBlock) {
588 if (!child->avoidsFloats() && childRenderBlock->containsFloats())
589 childRenderBlockFlow->markAllDescendantsWithFloatsForLayout();
590 if (!child->needsLayout())
591 child->markForPaginationRelayoutIfNeeded(layoutScope);
594 // Our guess was wrong. Make the child lay itself out again.
595 child->layoutIfNeeded();
598 // If we previously encountered a self-collapsing sibling of this child that had clearance then
599 // we set this bit to ensure we would not collapse the child's margins, and those of any subsequent
600 // self-collapsing siblings, with our parent. If this child is not self-collapsing then it can
601 // collapse its margins with the parent so reset the bit.
602 if (!marginInfo.canCollapseMarginAfterWithLastChild() && !childIsSelfCollapsing)
603 marginInfo.setCanCollapseMarginAfterWithLastChild(true);
605 // We are no longer at the top of the block if we encounter a non-empty child.
606 // This has to be done after checking for clear, so that margins can be reset if a clear occurred.
607 if (marginInfo.atBeforeSideOfBlock() && !childIsSelfCollapsing)
608 marginInfo.setAtBeforeSideOfBlock(false);
610 // Now place the child in the correct left position
611 determineLogicalLeftPositionForChild(child, ApplyLayoutDelta);
613 LayoutSize childOffset = child->location() - oldRect.location();
615 // Update our height now that the child has been placed in the correct position.
616 setLogicalHeight(logicalHeight() + logicalHeightForChild(child));
617 if (mustSeparateMarginAfterForChild(child)) {
618 setLogicalHeight(logicalHeight() + marginAfterForChild(child));
619 marginInfo.clearMargin();
621 // If the child has overhanging floats that intrude into following siblings (or possibly out
622 // of this block), then the parent gets notified of the floats now.
623 if (childRenderBlockFlow)
624 addOverhangingFloats(childRenderBlockFlow, !childNeededLayout);
626 if (childOffset.width() || childOffset.height()) {
627 if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
628 view()->addLayoutDelta(childOffset);
630 // If the child moved, we have to repaint it as well as any floating/positioned
631 // descendants. An exception is if we need a layout. In this case, we know we're going to
632 // repaint ourselves (and the child) anyway.
633 if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled() && childHadLayout && !selfNeedsLayout())
634 child->repaintOverhangingFloats(true);
635 else if (childHadLayout && !selfNeedsLayout() && child->checkForPaintInvalidationDuringLayout())
636 child->repaintDuringLayoutIfMoved(oldRect);
639 if (!childHadLayout && child->checkForPaintInvalidation()) {
640 if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
641 child->paintInvalidationForWholeRenderer();
642 child->repaintOverhangingFloats(true);
646 // Check for an after page/column break.
647 LayoutUnit newHeight = applyAfterBreak(child, logicalHeight(), marginInfo);
648 if (newHeight != height())
649 setLogicalHeight(newHeight);
652 if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled()) {
653 ASSERT(view()->layoutDeltaMatches(oldLayoutDelta));
657 LayoutUnit RenderBlockFlow::adjustBlockChildForPagination(LayoutUnit logicalTopAfterClear, LayoutUnit estimateWithoutPagination, RenderBox* child, bool atBeforeSideOfBlock)
659 RenderBlock* childRenderBlock = child->isRenderBlock() ? toRenderBlock(child) : 0;
661 if (estimateWithoutPagination != logicalTopAfterClear) {
662 // Our guess prior to pagination movement was wrong. Before we attempt to paginate, let's try again at the new
664 setLogicalHeight(logicalTopAfterClear);
665 setLogicalTopForChild(child, logicalTopAfterClear, ApplyLayoutDelta);
667 if (child->shrinkToAvoidFloats()) {
668 // The child's width depends on the line width.
669 // When the child shifts to clear an item, its width can
670 // change (because it has more available line width).
671 // So go ahead and mark the item as dirty.
672 child->setChildNeedsLayout(MarkOnlyThis);
675 SubtreeLayoutScope layoutScope(*child);
677 if (childRenderBlock) {
678 if (!child->avoidsFloats() && childRenderBlock->containsFloats())
679 toRenderBlockFlow(childRenderBlock)->markAllDescendantsWithFloatsForLayout();
680 if (!child->needsLayout())
681 child->markForPaginationRelayoutIfNeeded(layoutScope);
684 // Our guess was wrong. Make the child lay itself out again.
685 child->layoutIfNeeded();
688 LayoutUnit oldTop = logicalTopAfterClear;
690 // If the object has a page or column break value of "before", then we should shift to the top of the next page.
691 LayoutUnit result = applyBeforeBreak(child, logicalTopAfterClear);
693 // For replaced elements and scrolled elements, we want to shift them to the next page if they don't fit on the current one.
694 LayoutUnit logicalTopBeforeUnsplittableAdjustment = result;
695 LayoutUnit logicalTopAfterUnsplittableAdjustment = adjustForUnsplittableChild(child, result);
697 LayoutUnit paginationStrut = 0;
698 LayoutUnit unsplittableAdjustmentDelta = logicalTopAfterUnsplittableAdjustment - logicalTopBeforeUnsplittableAdjustment;
699 LayoutUnit childLogicalHeight = child->logicalHeight();
700 if (unsplittableAdjustmentDelta) {
701 setPageBreak(result, childLogicalHeight - unsplittableAdjustmentDelta);
702 paginationStrut = unsplittableAdjustmentDelta;
703 } else if (childRenderBlock && childRenderBlock->paginationStrut()) {
704 paginationStrut = childRenderBlock->paginationStrut();
707 if (paginationStrut) {
708 // We are willing to propagate out to our parent block as long as we were at the top of the block prior
709 // to collapsing our margins, and as long as we didn't clear or move as a result of other pagination.
710 if (atBeforeSideOfBlock && oldTop == result && !isOutOfFlowPositioned() && !isTableCell()) {
711 // FIXME: Should really check if we're exceeding the page height before propagating the strut, but we don't
712 // have all the information to do so (the strut only has the remaining amount to push). Gecko gets this wrong too
713 // and pushes to the next page anyway, so not too concerned about it.
714 setPaginationStrut(result + paginationStrut);
715 if (childRenderBlock)
716 childRenderBlock->setPaginationStrut(0);
718 result += paginationStrut;
722 if (!unsplittableAdjustmentDelta) {
723 if (LayoutUnit pageLogicalHeight = pageLogicalHeightForOffset(result)) {
724 LayoutUnit remainingLogicalHeight = pageRemainingLogicalHeightForOffset(result, ExcludePageBoundary);
725 LayoutUnit spaceShortage = childLogicalHeight - remainingLogicalHeight;
726 if (spaceShortage > 0) {
727 // If the child crosses a column boundary, report a break, in case nothing inside it
728 // has already done so. The column balancer needs to know how much it has to stretch
729 // the columns to make more content fit. If no breaks are reported (but do occur),
730 // the balancer will have no clue. Only measure the space after the last column
731 // boundary, in case it crosses more than one.
732 LayoutUnit spaceShortageInLastColumn = intMod(spaceShortage, pageLogicalHeight);
733 setPageBreak(result, spaceShortageInLastColumn ? spaceShortageInLastColumn : spaceShortage);
734 } else if (remainingLogicalHeight == pageLogicalHeight && offsetFromLogicalTopOfFirstPage() + child->logicalTop()) {
735 // We're at the very top of a page or column, and it's not the first one. This child
736 // may turn out to be the smallest piece of content that causes a page break, so we
737 // need to report it.
738 setPageBreak(result, childLogicalHeight);
743 // Similar to how we apply clearance. Go ahead and boost height() to be the place where we're going to position the child.
744 setLogicalHeight(logicalHeight() + (result - oldTop));
746 // Return the final adjusted logical top.
750 void RenderBlockFlow::rebuildFloatsFromIntruding()
752 if (m_floatingObjects)
753 m_floatingObjects->setHorizontalWritingMode(isHorizontalWritingMode());
755 HashSet<RenderBox*> oldIntrudingFloatSet;
756 if (!childrenInline() && m_floatingObjects) {
757 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
758 FloatingObjectSetIterator end = floatingObjectSet.end();
759 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
760 FloatingObject* floatingObject = it->get();
761 if (!floatingObject->isDescendant())
762 oldIntrudingFloatSet.add(floatingObject->renderer());
766 // Inline blocks are covered by the isReplaced() check in the avoidFloats method.
767 if (avoidsOrIgnoresFloats() || isRenderView()) {
768 if (m_floatingObjects) {
769 m_floatingObjects->clear();
771 if (!oldIntrudingFloatSet.isEmpty())
772 markAllDescendantsWithFloatsForLayout();
776 RendererToFloatInfoMap floatMap;
778 if (m_floatingObjects) {
779 if (childrenInline())
780 m_floatingObjects->moveAllToFloatInfoMap(floatMap);
782 m_floatingObjects->clear();
785 // We should not process floats if the parent node is not a RenderBlockFlow. Otherwise, we will add
786 // floats in an invalid context. This will cause a crash arising from a bad cast on the parent.
787 // See <rdar://problem/8049753>, where float property is applied on a text node in a SVG.
788 if (!parent() || !parent()->isRenderBlockFlow())
791 // Attempt to locate a previous sibling with overhanging floats. We skip any elements that
792 // may have shifted to avoid floats, and any objects whose floats cannot interact with objects
793 // outside it (i.e. objects that create a new block formatting context).
794 RenderBlockFlow* parentBlockFlow = toRenderBlockFlow(parent());
795 bool parentHasFloats = false;
796 RenderObject* prev = previousSibling();
797 while (prev && (!prev->isBox() || !prev->isRenderBlock() || toRenderBlock(prev)->avoidsOrIgnoresFloats())) {
798 if (prev->isFloating())
799 parentHasFloats = true;
800 prev = prev->previousSibling();
803 // First add in floats from the parent. Self-collapsing blocks let their parent track any floats that intrude into
804 // them (as opposed to floats they contain themselves) so check for those here too.
805 LayoutUnit logicalTopOffset = logicalTop();
806 bool parentHasIntrudingFloats = !parentHasFloats && (!prev || toRenderBlockFlow(prev)->isSelfCollapsingBlock()) && parentBlockFlow->lowestFloatLogicalBottom() > logicalTopOffset;
807 if (parentHasFloats || parentHasIntrudingFloats)
808 addIntrudingFloats(parentBlockFlow, parentBlockFlow->logicalLeftOffsetForContent(), logicalTopOffset);
810 // Add overhanging floats from the previous RenderBlockFlow, but only if it has a float that intrudes into our space.
812 RenderBlockFlow* blockFlow = toRenderBlockFlow(prev);
813 logicalTopOffset -= blockFlow->logicalTop();
814 if (blockFlow->lowestFloatLogicalBottom() > logicalTopOffset)
815 addIntrudingFloats(blockFlow, 0, logicalTopOffset);
818 if (childrenInline()) {
819 LayoutUnit changeLogicalTop = LayoutUnit::max();
820 LayoutUnit changeLogicalBottom = LayoutUnit::min();
821 if (m_floatingObjects) {
822 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
823 FloatingObjectSetIterator end = floatingObjectSet.end();
824 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
825 FloatingObject* floatingObject = it->get();
826 FloatingObject* oldFloatingObject = floatMap.get(floatingObject->renderer());
827 LayoutUnit logicalBottom = logicalBottomForFloat(floatingObject);
828 if (oldFloatingObject) {
829 LayoutUnit oldLogicalBottom = logicalBottomForFloat(oldFloatingObject);
830 if (logicalWidthForFloat(floatingObject) != logicalWidthForFloat(oldFloatingObject) || logicalLeftForFloat(floatingObject) != logicalLeftForFloat(oldFloatingObject)) {
831 changeLogicalTop = 0;
832 changeLogicalBottom = max(changeLogicalBottom, max(logicalBottom, oldLogicalBottom));
834 if (logicalBottom != oldLogicalBottom) {
835 changeLogicalTop = min(changeLogicalTop, min(logicalBottom, oldLogicalBottom));
836 changeLogicalBottom = max(changeLogicalBottom, max(logicalBottom, oldLogicalBottom));
838 LayoutUnit logicalTop = logicalTopForFloat(floatingObject);
839 LayoutUnit oldLogicalTop = logicalTopForFloat(oldFloatingObject);
840 if (logicalTop != oldLogicalTop) {
841 changeLogicalTop = min(changeLogicalTop, min(logicalTop, oldLogicalTop));
842 changeLogicalBottom = max(changeLogicalBottom, max(logicalTop, oldLogicalTop));
846 if (oldFloatingObject->originatingLine() && !selfNeedsLayout()) {
847 ASSERT(oldFloatingObject->originatingLine()->renderer() == this);
848 oldFloatingObject->originatingLine()->markDirty();
851 floatMap.remove(floatingObject->renderer());
853 changeLogicalTop = 0;
854 changeLogicalBottom = max(changeLogicalBottom, logicalBottom);
859 RendererToFloatInfoMap::iterator end = floatMap.end();
860 for (RendererToFloatInfoMap::iterator it = floatMap.begin(); it != end; ++it) {
861 OwnPtr<FloatingObject>& floatingObject = it->value;
862 if (!floatingObject->isDescendant()) {
863 changeLogicalTop = 0;
864 changeLogicalBottom = max(changeLogicalBottom, logicalBottomForFloat(floatingObject.get()));
868 markLinesDirtyInBlockRange(changeLogicalTop, changeLogicalBottom);
869 } else if (!oldIntrudingFloatSet.isEmpty()) {
870 // If there are previously intruding floats that no longer intrude, then children with floats
871 // should also get layout because they might need their floating object lists cleared.
872 if (m_floatingObjects->set().size() < oldIntrudingFloatSet.size()) {
873 markAllDescendantsWithFloatsForLayout();
875 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
876 FloatingObjectSetIterator end = floatingObjectSet.end();
877 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end && !oldIntrudingFloatSet.isEmpty(); ++it)
878 oldIntrudingFloatSet.remove((*it)->renderer());
879 if (!oldIntrudingFloatSet.isEmpty())
880 markAllDescendantsWithFloatsForLayout();
885 void RenderBlockFlow::layoutBlockChildren(bool relayoutChildren, SubtreeLayoutScope& layoutScope, LayoutUnit beforeEdge, LayoutUnit afterEdge)
887 dirtyForLayoutFromPercentageHeightDescendants(layoutScope);
889 // The margin struct caches all our current margin collapsing state. The compact struct caches state when we encounter compacts,
890 MarginInfo marginInfo(this, beforeEdge, afterEdge);
892 // Fieldsets need to find their legend and position it inside the border of the object.
893 // The legend then gets skipped during normal layout. The same is true for ruby text.
894 // It doesn't get included in the normal layout process but is instead skipped.
895 RenderObject* childToExclude = layoutSpecialExcludedChild(relayoutChildren, layoutScope);
897 LayoutUnit previousFloatLogicalBottom = 0;
899 RenderBox* next = firstChildBox();
900 RenderBox* lastNormalFlowChild = 0;
903 RenderBox* child = next;
904 next = child->nextSiblingBox();
906 // FIXME: this should only be set from clearNeedsLayout crbug.com/361250
907 child->setLayoutDidGetCalled(true);
909 if (childToExclude == child)
910 continue; // Skip this child, since it will be positioned by the specialized subclass (fieldsets and ruby runs).
912 updateBlockChildDirtyBitsBeforeLayout(relayoutChildren, child);
914 if (child->isOutOfFlowPositioned()) {
915 child->containingBlock()->insertPositionedObject(child);
916 adjustPositionedBlock(child, marginInfo);
919 if (child->isFloating()) {
920 insertFloatingObject(child);
921 adjustFloatingBlock(marginInfo);
925 // Lay out the child.
926 layoutBlockChild(child, marginInfo, previousFloatLogicalBottom);
927 lastNormalFlowChild = child;
930 // Now do the handling of the bottom of the block, adding in our bottom border/padding and
931 // determining the correct collapsed bottom margin information.
932 handleAfterSideOfBlock(lastNormalFlowChild, beforeEdge, afterEdge, marginInfo);
935 // Our MarginInfo state used when laying out block children.
936 MarginInfo::MarginInfo(RenderBlockFlow* blockFlow, LayoutUnit beforeBorderPadding, LayoutUnit afterBorderPadding)
937 : m_canCollapseMarginAfterWithLastChild(true)
938 , m_atBeforeSideOfBlock(true)
939 , m_atAfterSideOfBlock(false)
940 , m_hasMarginBeforeQuirk(false)
941 , m_hasMarginAfterQuirk(false)
942 , m_determinedMarginBeforeQuirk(false)
943 , m_discardMargin(false)
945 RenderStyle* blockStyle = blockFlow->style();
946 ASSERT(blockFlow->isRenderView() || blockFlow->parent());
947 m_canCollapseWithChildren = !blockFlow->createsBlockFormattingContext() && !blockFlow->isRenderFlowThread() && !blockFlow->isRenderView();
949 m_canCollapseMarginBeforeWithChildren = m_canCollapseWithChildren && !beforeBorderPadding && blockStyle->marginBeforeCollapse() != MSEPARATE;
951 // If any height other than auto is specified in CSS, then we don't collapse our bottom
952 // margins with our children's margins. To do otherwise would be to risk odd visual
953 // effects when the children overflow out of the parent block and yet still collapse
954 // with it. We also don't collapse if we have any bottom border/padding.
955 m_canCollapseMarginAfterWithChildren = m_canCollapseWithChildren && !afterBorderPadding
956 && (blockStyle->logicalHeight().isAuto() && !blockStyle->logicalHeight().value()) && blockStyle->marginAfterCollapse() != MSEPARATE;
958 m_quirkContainer = blockFlow->isTableCell() || blockFlow->isBody();
960 m_discardMargin = m_canCollapseMarginBeforeWithChildren && blockFlow->mustDiscardMarginBefore();
962 m_positiveMargin = (m_canCollapseMarginBeforeWithChildren && !blockFlow->mustDiscardMarginBefore()) ? blockFlow->maxPositiveMarginBefore() : LayoutUnit();
963 m_negativeMargin = (m_canCollapseMarginBeforeWithChildren && !blockFlow->mustDiscardMarginBefore()) ? blockFlow->maxNegativeMarginBefore() : LayoutUnit();
966 RenderBlockFlow::MarginValues RenderBlockFlow::marginValuesForChild(RenderBox* child) const
968 LayoutUnit childBeforePositive = 0;
969 LayoutUnit childBeforeNegative = 0;
970 LayoutUnit childAfterPositive = 0;
971 LayoutUnit childAfterNegative = 0;
973 LayoutUnit beforeMargin = 0;
974 LayoutUnit afterMargin = 0;
976 RenderBlockFlow* childRenderBlockFlow = child->isRenderBlockFlow() ? toRenderBlockFlow(child) : 0;
978 // If the child has the same directionality as we do, then we can just return its
979 // margins in the same direction.
980 if (!child->isWritingModeRoot()) {
981 if (childRenderBlockFlow) {
982 childBeforePositive = childRenderBlockFlow->maxPositiveMarginBefore();
983 childBeforeNegative = childRenderBlockFlow->maxNegativeMarginBefore();
984 childAfterPositive = childRenderBlockFlow->maxPositiveMarginAfter();
985 childAfterNegative = childRenderBlockFlow->maxNegativeMarginAfter();
987 beforeMargin = child->marginBefore();
988 afterMargin = child->marginAfter();
990 } else if (child->isHorizontalWritingMode() == isHorizontalWritingMode()) {
991 // The child has a different directionality. If the child is parallel, then it's just
992 // flipped relative to us. We can use the margins for the opposite edges.
993 if (childRenderBlockFlow) {
994 childBeforePositive = childRenderBlockFlow->maxPositiveMarginAfter();
995 childBeforeNegative = childRenderBlockFlow->maxNegativeMarginAfter();
996 childAfterPositive = childRenderBlockFlow->maxPositiveMarginBefore();
997 childAfterNegative = childRenderBlockFlow->maxNegativeMarginBefore();
999 beforeMargin = child->marginAfter();
1000 afterMargin = child->marginBefore();
1003 // The child is perpendicular to us, which means its margins don't collapse but are on the
1004 // "logical left/right" sides of the child box. We can just return the raw margin in this case.
1005 beforeMargin = marginBeforeForChild(child);
1006 afterMargin = marginAfterForChild(child);
1009 // Resolve uncollapsing margins into their positive/negative buckets.
1011 if (beforeMargin > 0)
1012 childBeforePositive = beforeMargin;
1014 childBeforeNegative = -beforeMargin;
1017 if (afterMargin > 0)
1018 childAfterPositive = afterMargin;
1020 childAfterNegative = -afterMargin;
1023 return RenderBlockFlow::MarginValues(childBeforePositive, childBeforeNegative, childAfterPositive, childAfterNegative);
1026 LayoutUnit RenderBlockFlow::collapseMargins(RenderBox* child, MarginInfo& marginInfo, bool childIsSelfCollapsing)
1028 bool childDiscardMarginBefore = mustDiscardMarginBeforeForChild(child);
1029 bool childDiscardMarginAfter = mustDiscardMarginAfterForChild(child);
1031 // The child discards the before margin when the the after margin has discard in the case of a self collapsing block.
1032 childDiscardMarginBefore = childDiscardMarginBefore || (childDiscardMarginAfter && childIsSelfCollapsing);
1034 // Get the four margin values for the child and cache them.
1035 const RenderBlockFlow::MarginValues childMargins = marginValuesForChild(child);
1037 // Get our max pos and neg top margins.
1038 LayoutUnit posTop = childMargins.positiveMarginBefore();
1039 LayoutUnit negTop = childMargins.negativeMarginBefore();
1041 // For self-collapsing blocks, collapse our bottom margins into our
1042 // top to get new posTop and negTop values.
1043 if (childIsSelfCollapsing) {
1044 posTop = max(posTop, childMargins.positiveMarginAfter());
1045 negTop = max(negTop, childMargins.negativeMarginAfter());
1048 // See if the top margin is quirky. We only care if this child has
1049 // margins that will collapse with us.
1050 bool topQuirk = hasMarginBeforeQuirk(child);
1052 if (marginInfo.canCollapseWithMarginBefore()) {
1053 if (!childDiscardMarginBefore && !marginInfo.discardMargin()) {
1054 // This child is collapsing with the top of the
1055 // block. If it has larger margin values, then we need to update
1056 // our own maximal values.
1057 if (!document().inQuirksMode() || !marginInfo.quirkContainer() || !topQuirk)
1058 setMaxMarginBeforeValues(max(posTop, maxPositiveMarginBefore()), max(negTop, maxNegativeMarginBefore()));
1060 // The minute any of the margins involved isn't a quirk, don't
1061 // collapse it away, even if the margin is smaller (www.webreference.com
1062 // has an example of this, a <dt> with 0.8em author-specified inside
1063 // a <dl> inside a <td>.
1064 if (!marginInfo.determinedMarginBeforeQuirk() && !topQuirk && (posTop - negTop)) {
1065 setHasMarginBeforeQuirk(false);
1066 marginInfo.setDeterminedMarginBeforeQuirk(true);
1069 if (!marginInfo.determinedMarginBeforeQuirk() && topQuirk && !marginBefore()) {
1070 // We have no top margin and our top child has a quirky margin.
1071 // We will pick up this quirky margin and pass it through.
1072 // This deals with the <td><div><p> case.
1073 // Don't do this for a block that split two inlines though. You do
1074 // still apply margins in this case.
1075 setHasMarginBeforeQuirk(true);
1078 // The before margin of the container will also discard all the margins it is collapsing with.
1079 setMustDiscardMarginBefore();
1083 // Once we find a child with discardMarginBefore all the margins collapsing with us must also discard.
1084 if (childDiscardMarginBefore) {
1085 marginInfo.setDiscardMargin(true);
1086 marginInfo.clearMargin();
1089 if (marginInfo.quirkContainer() && marginInfo.atBeforeSideOfBlock() && (posTop - negTop))
1090 marginInfo.setHasMarginBeforeQuirk(topQuirk);
1092 LayoutUnit beforeCollapseLogicalTop = logicalHeight();
1093 LayoutUnit logicalTop = beforeCollapseLogicalTop;
1095 LayoutUnit clearanceForSelfCollapsingBlock;
1096 RenderObject* prev = child->previousSibling();
1097 RenderBlockFlow* previousBlockFlow = prev && prev->isRenderBlockFlow() && !prev->isFloatingOrOutOfFlowPositioned() ? toRenderBlockFlow(prev) : 0;
1098 // If the child's previous sibling is a self-collapsing block that cleared a float then its top border edge has been set at the bottom border edge
1099 // of the float. Since we want to collapse the child's top margin with the self-collapsing block's top and bottom margins we need to adjust our parent's height to match the
1100 // margin top of the self-collapsing block. If the resulting collapsed margin leaves the child still intruding into the float then we will want to clear it.
1101 if (!marginInfo.canCollapseWithMarginBefore() && previousBlockFlow && previousBlockFlow->isSelfCollapsingBlock()) {
1102 clearanceForSelfCollapsingBlock = previousBlockFlow->marginOffsetForSelfCollapsingBlock();
1103 setLogicalHeight(logicalHeight() - clearanceForSelfCollapsingBlock);
1106 if (childIsSelfCollapsing) {
1107 // For a self collapsing block both the before and after margins get discarded. The block doesn't contribute anything to the height of the block.
1108 // Also, the child's top position equals the logical height of the container.
1109 if (!childDiscardMarginBefore && !marginInfo.discardMargin()) {
1110 // This child has no height. We need to compute our
1111 // position before we collapse the child's margins together,
1112 // so that we can get an accurate position for the zero-height block.
1113 LayoutUnit collapsedBeforePos = max(marginInfo.positiveMargin(), childMargins.positiveMarginBefore());
1114 LayoutUnit collapsedBeforeNeg = max(marginInfo.negativeMargin(), childMargins.negativeMarginBefore());
1115 marginInfo.setMargin(collapsedBeforePos, collapsedBeforeNeg);
1117 // Now collapse the child's margins together, which means examining our
1118 // bottom margin values as well.
1119 marginInfo.setPositiveMarginIfLarger(childMargins.positiveMarginAfter());
1120 marginInfo.setNegativeMarginIfLarger(childMargins.negativeMarginAfter());
1122 if (!marginInfo.canCollapseWithMarginBefore()) {
1123 // We need to make sure that the position of the self-collapsing block
1124 // is correct, since it could have overflowing content
1125 // that needs to be positioned correctly (e.g., a block that
1126 // had a specified height of 0 but that actually had subcontent).
1127 logicalTop = logicalHeight() + collapsedBeforePos - collapsedBeforeNeg;
1131 if (mustSeparateMarginBeforeForChild(child)) {
1132 ASSERT(!marginInfo.discardMargin() || (marginInfo.discardMargin() && !marginInfo.margin()));
1133 // If we are at the before side of the block and we collapse, ignore the computed margin
1134 // and just add the child margin to the container height. This will correctly position
1135 // the child inside the container.
1136 LayoutUnit separateMargin = !marginInfo.canCollapseWithMarginBefore() ? marginInfo.margin() : LayoutUnit(0);
1137 setLogicalHeight(logicalHeight() + separateMargin + marginBeforeForChild(child));
1138 logicalTop = logicalHeight();
1139 } else if (!marginInfo.discardMargin() && (!marginInfo.atBeforeSideOfBlock()
1140 || (!marginInfo.canCollapseMarginBeforeWithChildren()
1141 && (!document().inQuirksMode() || !marginInfo.quirkContainer() || !marginInfo.hasMarginBeforeQuirk())))) {
1142 // We're collapsing with a previous sibling's margins and not
1143 // with the top of the block.
1144 setLogicalHeight(logicalHeight() + max(marginInfo.positiveMargin(), posTop) - max(marginInfo.negativeMargin(), negTop));
1145 logicalTop = logicalHeight();
1148 marginInfo.setDiscardMargin(childDiscardMarginAfter);
1150 if (!marginInfo.discardMargin()) {
1151 marginInfo.setPositiveMargin(childMargins.positiveMarginAfter());
1152 marginInfo.setNegativeMargin(childMargins.negativeMarginAfter());
1154 marginInfo.clearMargin();
1157 if (marginInfo.margin())
1158 marginInfo.setHasMarginAfterQuirk(hasMarginAfterQuirk(child));
1161 // If margins would pull us past the top of the next page, then we need to pull back and pretend like the margins
1162 // collapsed into the page edge.
1163 LayoutState* layoutState = view()->layoutState();
1164 if (layoutState->isPaginated() && layoutState->pageLogicalHeight() && logicalTop > beforeCollapseLogicalTop) {
1165 LayoutUnit oldLogicalTop = logicalTop;
1166 logicalTop = min(logicalTop, nextPageLogicalTop(beforeCollapseLogicalTop));
1167 setLogicalHeight(logicalHeight() + (logicalTop - oldLogicalTop));
1170 if (previousBlockFlow) {
1171 // If |child| is a self-collapsing block it may have collapsed into a previous sibling and although it hasn't reduced the height of the parent yet
1172 // any floats from the parent will now overhang.
1173 LayoutUnit oldLogicalHeight = logicalHeight();
1174 setLogicalHeight(logicalTop);
1175 if (!previousBlockFlow->avoidsFloats() && (previousBlockFlow->logicalTop() + previousBlockFlow->lowestFloatLogicalBottom()) > logicalTop)
1176 addOverhangingFloats(previousBlockFlow, false);
1177 setLogicalHeight(oldLogicalHeight);
1179 // If |child|'s previous sibling is a self-collapsing block that cleared a float and margin collapsing resulted in |child| moving up
1180 // into the margin area of the self-collapsing block then the float it clears is now intruding into |child|. Layout again so that we can look for
1181 // floats in the parent that overhang |child|'s new logical top.
1182 bool logicalTopIntrudesIntoFloat = clearanceForSelfCollapsingBlock > 0 && logicalTop < beforeCollapseLogicalTop;
1183 if (logicalTopIntrudesIntoFloat && containsFloats() && !child->avoidsFloats() && lowestFloatLogicalBottom() > logicalTop)
1184 child->setNeedsLayoutAndFullPaintInvalidation();
1190 void RenderBlockFlow::adjustPositionedBlock(RenderBox* child, const MarginInfo& marginInfo)
1192 bool isHorizontal = isHorizontalWritingMode();
1193 bool hasStaticBlockPosition = child->style()->hasStaticBlockPosition(isHorizontal);
1195 LayoutUnit logicalTop = logicalHeight();
1196 updateStaticInlinePositionForChild(child, logicalTop);
1198 if (!marginInfo.canCollapseWithMarginBefore()) {
1199 // Positioned blocks don't collapse margins, so add the margin provided by
1200 // the container now. The child's own margin is added later when calculating its logical top.
1201 LayoutUnit collapsedBeforePos = marginInfo.positiveMargin();
1202 LayoutUnit collapsedBeforeNeg = marginInfo.negativeMargin();
1203 logicalTop += collapsedBeforePos - collapsedBeforeNeg;
1206 RenderLayer* childLayer = child->layer();
1207 if (childLayer->staticBlockPosition() != logicalTop) {
1208 childLayer->setStaticBlockPosition(logicalTop);
1209 if (hasStaticBlockPosition)
1210 child->setChildNeedsLayout(MarkOnlyThis);
1214 LayoutUnit RenderBlockFlow::computeStartPositionDeltaForChildAvoidingFloats(const RenderBox* child, LayoutUnit childMarginStart)
1216 LayoutUnit startPosition = startOffsetForContent();
1218 // Add in our start margin.
1219 LayoutUnit oldPosition = startPosition + childMarginStart;
1220 LayoutUnit newPosition = oldPosition;
1222 LayoutUnit blockOffset = logicalTopForChild(child);
1223 LayoutUnit startOff = startOffsetForLine(blockOffset, false, logicalHeightForChild(child));
1225 if (style()->textAlign() != WEBKIT_CENTER && !child->style()->marginStartUsing(style()).isAuto()) {
1226 if (childMarginStart < 0)
1227 startOff += childMarginStart;
1228 newPosition = max(newPosition, startOff); // Let the float sit in the child's margin if it can fit.
1229 } else if (startOff != startPosition) {
1230 newPosition = startOff + childMarginStart;
1233 return newPosition - oldPosition;
1236 LayoutUnit RenderBlockFlow::clearFloatsIfNeeded(RenderBox* child, MarginInfo& marginInfo, LayoutUnit oldTopPosMargin, LayoutUnit oldTopNegMargin, LayoutUnit yPos, bool childIsSelfCollapsing)
1238 LayoutUnit heightIncrease = getClearDelta(child, yPos);
1239 if (!heightIncrease)
1242 if (childIsSelfCollapsing) {
1243 bool childDiscardMargin = mustDiscardMarginBeforeForChild(child) || mustDiscardMarginAfterForChild(child);
1245 // For self-collapsing blocks that clear, they can still collapse their
1246 // margins with following siblings. Reset the current margins to represent
1247 // the self-collapsing block's margins only.
1248 // If DISCARD is specified for -webkit-margin-collapse, reset the margin values.
1249 RenderBlockFlow::MarginValues childMargins = marginValuesForChild(child);
1250 if (!childDiscardMargin) {
1251 marginInfo.setPositiveMargin(max(childMargins.positiveMarginBefore(), childMargins.positiveMarginAfter()));
1252 marginInfo.setNegativeMargin(max(childMargins.negativeMarginBefore(), childMargins.negativeMarginAfter()));
1254 marginInfo.clearMargin();
1256 marginInfo.setDiscardMargin(childDiscardMargin);
1259 // "If the top and bottom margins of an element with clearance are adjoining, its margins collapse with
1260 // the adjoining margins of following siblings but that resulting margin does not collapse with the bottom margin of the parent block."
1261 // So the parent's bottom margin cannot collapse through this block or any subsequent self-collapsing blocks. Set a bit to ensure
1262 // this happens; it will get reset if we encounter an in-flow sibling that is not self-collapsing.
1263 marginInfo.setCanCollapseMarginAfterWithLastChild(false);
1265 // For now set the border-top of |child| flush with the bottom border-edge of the float so it can layout any floating or positioned children of
1266 // its own at the correct vertical position. If subsequent siblings attempt to collapse with |child|'s margins in |collapseMargins| we will
1267 // adjust the height of the parent to |child|'s margin top (which if it is positive sits up 'inside' the float it's clearing) so that all three
1268 // margins can collapse at the correct vertical position.
1269 // Per CSS2.1 we need to ensure that any negative margin-top clears |child| beyond the bottom border-edge of the float so that the top border edge of the child
1270 // (i.e. its clearance) is at a position that satisfies the equation: "the amount of clearance is set so that clearance + margin-top = [height of float],
1271 // i.e., clearance = [height of float] - margin-top".
1272 setLogicalHeight(child->logicalTop() + childMargins.negativeMarginBefore());
1274 // Increase our height by the amount we had to clear.
1275 setLogicalHeight(logicalHeight() + heightIncrease);
1278 if (marginInfo.canCollapseWithMarginBefore()) {
1279 // We can no longer collapse with the top of the block since a clear
1280 // occurred. The empty blocks collapse into the cleared block.
1281 setMaxMarginBeforeValues(oldTopPosMargin, oldTopNegMargin);
1282 marginInfo.setAtBeforeSideOfBlock(false);
1284 // In case the child discarded the before margin of the block we need to reset the mustDiscardMarginBefore flag to the initial value.
1285 setMustDiscardMarginBefore(style()->marginBeforeCollapse() == MDISCARD);
1288 return yPos + heightIncrease;
1291 void RenderBlockFlow::setCollapsedBottomMargin(const MarginInfo& marginInfo)
1293 if (marginInfo.canCollapseWithMarginAfter() && !marginInfo.canCollapseWithMarginBefore()) {
1294 // Update the after side margin of the container to discard if the after margin of the last child also discards and we collapse with it.
1295 // Don't update the max margin values because we won't need them anyway.
1296 if (marginInfo.discardMargin()) {
1297 setMustDiscardMarginAfter();
1301 // Update our max pos/neg bottom margins, since we collapsed our bottom margins
1302 // with our children.
1303 setMaxMarginAfterValues(max(maxPositiveMarginAfter(), marginInfo.positiveMargin()), max(maxNegativeMarginAfter(), marginInfo.negativeMargin()));
1305 if (!marginInfo.hasMarginAfterQuirk())
1306 setHasMarginAfterQuirk(false);
1308 if (marginInfo.hasMarginAfterQuirk() && !marginAfter()) {
1309 // We have no bottom margin and our last child has a quirky margin.
1310 // We will pick up this quirky margin and pass it through.
1311 // This deals with the <td><div><p> case.
1312 setHasMarginAfterQuirk(true);
1317 void RenderBlockFlow::marginBeforeEstimateForChild(RenderBox* child, LayoutUnit& positiveMarginBefore, LayoutUnit& negativeMarginBefore, bool& discardMarginBefore) const
1319 // Give up if in quirks mode and we're a body/table cell and the top margin of the child box is quirky.
1320 // Give up if the child specified -webkit-margin-collapse: separate that prevents collapsing.
1321 // FIXME: Use writing mode independent accessor for marginBeforeCollapse.
1322 if ((document().inQuirksMode() && hasMarginBeforeQuirk(child) && (isTableCell() || isBody())) || child->style()->marginBeforeCollapse() == MSEPARATE)
1325 // The margins are discarded by a child that specified -webkit-margin-collapse: discard.
1326 // FIXME: Use writing mode independent accessor for marginBeforeCollapse.
1327 if (child->style()->marginBeforeCollapse() == MDISCARD) {
1328 positiveMarginBefore = 0;
1329 negativeMarginBefore = 0;
1330 discardMarginBefore = true;
1334 LayoutUnit beforeChildMargin = marginBeforeForChild(child);
1335 positiveMarginBefore = max(positiveMarginBefore, beforeChildMargin);
1336 negativeMarginBefore = max(negativeMarginBefore, -beforeChildMargin);
1338 if (!child->isRenderBlockFlow())
1341 RenderBlockFlow* childBlockFlow = toRenderBlockFlow(child);
1342 if (childBlockFlow->childrenInline() || childBlockFlow->isWritingModeRoot())
1345 MarginInfo childMarginInfo(childBlockFlow, childBlockFlow->borderBefore() + childBlockFlow->paddingBefore(), childBlockFlow->borderAfter() + childBlockFlow->paddingAfter());
1346 if (!childMarginInfo.canCollapseMarginBeforeWithChildren())
1349 RenderBox* grandchildBox = childBlockFlow->firstChildBox();
1350 for ( ; grandchildBox; grandchildBox = grandchildBox->nextSiblingBox()) {
1351 if (!grandchildBox->isFloatingOrOutOfFlowPositioned())
1355 // Give up if there is clearance on the box, since it probably won't collapse into us.
1356 if (!grandchildBox || grandchildBox->style()->clear() != CNONE)
1359 // Make sure to update the block margins now for the grandchild box so that we're looking at current values.
1360 if (grandchildBox->needsLayout()) {
1361 grandchildBox->computeAndSetBlockDirectionMargins(this);
1362 if (grandchildBox->isRenderBlock()) {
1363 RenderBlock* grandchildBlock = toRenderBlock(grandchildBox);
1364 grandchildBlock->setHasMarginBeforeQuirk(grandchildBox->style()->hasMarginBeforeQuirk());
1365 grandchildBlock->setHasMarginAfterQuirk(grandchildBox->style()->hasMarginAfterQuirk());
1369 // Collapse the margin of the grandchild box with our own to produce an estimate.
1370 childBlockFlow->marginBeforeEstimateForChild(grandchildBox, positiveMarginBefore, negativeMarginBefore, discardMarginBefore);
1373 LayoutUnit RenderBlockFlow::estimateLogicalTopPosition(RenderBox* child, const MarginInfo& marginInfo, LayoutUnit& estimateWithoutPagination)
1375 // FIXME: We need to eliminate the estimation of vertical position, because when it's wrong we sometimes trigger a pathological
1376 // relayout if there are intruding floats.
1377 LayoutUnit logicalTopEstimate = logicalHeight();
1378 if (!marginInfo.canCollapseWithMarginBefore()) {
1379 LayoutUnit positiveMarginBefore = 0;
1380 LayoutUnit negativeMarginBefore = 0;
1381 bool discardMarginBefore = false;
1382 if (child->selfNeedsLayout()) {
1383 // Try to do a basic estimation of how the collapse is going to go.
1384 marginBeforeEstimateForChild(child, positiveMarginBefore, negativeMarginBefore, discardMarginBefore);
1386 // Use the cached collapsed margin values from a previous layout. Most of the time they
1388 RenderBlockFlow::MarginValues marginValues = marginValuesForChild(child);
1389 positiveMarginBefore = max(positiveMarginBefore, marginValues.positiveMarginBefore());
1390 negativeMarginBefore = max(negativeMarginBefore, marginValues.negativeMarginBefore());
1391 discardMarginBefore = mustDiscardMarginBeforeForChild(child);
1394 // Collapse the result with our current margins.
1395 if (!discardMarginBefore)
1396 logicalTopEstimate += max(marginInfo.positiveMargin(), positiveMarginBefore) - max(marginInfo.negativeMargin(), negativeMarginBefore);
1399 // Adjust logicalTopEstimate down to the next page if the margins are so large that we don't fit on the current
1401 LayoutState* layoutState = view()->layoutState();
1402 if (layoutState->isPaginated() && layoutState->pageLogicalHeight() && logicalTopEstimate > logicalHeight())
1403 logicalTopEstimate = min(logicalTopEstimate, nextPageLogicalTop(logicalHeight()));
1405 logicalTopEstimate += getClearDelta(child, logicalTopEstimate);
1407 estimateWithoutPagination = logicalTopEstimate;
1409 if (layoutState->isPaginated()) {
1410 // If the object has a page or column break value of "before", then we should shift to the top of the next page.
1411 logicalTopEstimate = applyBeforeBreak(child, logicalTopEstimate);
1413 // For replaced elements and scrolled elements, we want to shift them to the next page if they don't fit on the current one.
1414 logicalTopEstimate = adjustForUnsplittableChild(child, logicalTopEstimate);
1416 if (!child->selfNeedsLayout() && child->isRenderBlock())
1417 logicalTopEstimate += toRenderBlock(child)->paginationStrut();
1420 return logicalTopEstimate;
1423 LayoutUnit RenderBlockFlow::marginOffsetForSelfCollapsingBlock()
1425 ASSERT(isSelfCollapsingBlock());
1426 RenderBlockFlow* parentBlock = toRenderBlockFlow(parent());
1427 if (parentBlock && style()->clear() && parentBlock->getClearDelta(this, logicalHeight()))
1428 return marginValuesForChild(this).positiveMarginBefore();
1429 return LayoutUnit();
1432 void RenderBlockFlow::adjustFloatingBlock(const MarginInfo& marginInfo)
1434 // The float should be positioned taking into account the bottom margin
1435 // of the previous flow. We add that margin into the height, get the
1436 // float positioned properly, and then subtract the margin out of the
1437 // height again. In the case of self-collapsing blocks, we always just
1438 // use the top margins, since the self-collapsing block collapsed its
1439 // own bottom margin into its top margin.
1441 // Note also that the previous flow may collapse its margin into the top of
1442 // our block. If this is the case, then we do not add the margin in to our
1443 // height when computing the position of the float. This condition can be tested
1444 // for by simply calling canCollapseWithMarginBefore. See
1445 // http://www.hixie.ch/tests/adhoc/css/box/block/margin-collapse/046.html for
1446 // an example of this scenario.
1447 LayoutUnit marginOffset = marginInfo.canCollapseWithMarginBefore() ? LayoutUnit() : marginInfo.margin();
1448 setLogicalHeight(logicalHeight() + marginOffset);
1449 positionNewFloats();
1450 setLogicalHeight(logicalHeight() - marginOffset);
1453 void RenderBlockFlow::handleAfterSideOfBlock(RenderBox* lastChild, LayoutUnit beforeSide, LayoutUnit afterSide, MarginInfo& marginInfo)
1455 marginInfo.setAtAfterSideOfBlock(true);
1457 // If our last child was a self-collapsing block with clearance then our logical height is flush with the
1458 // bottom edge of the float that the child clears. The correct vertical position for the margin-collapsing we want
1459 // to perform now is at the child's margin-top - so adjust our height to that position.
1460 if (lastChild && lastChild->isRenderBlockFlow() && lastChild->isSelfCollapsingBlock())
1461 setLogicalHeight(logicalHeight() - toRenderBlockFlow(lastChild)->marginOffsetForSelfCollapsingBlock());
1463 if (marginInfo.canCollapseMarginAfterWithChildren() && !marginInfo.canCollapseMarginAfterWithLastChild())
1464 marginInfo.setCanCollapseMarginAfterWithChildren(false);
1466 // If we can't collapse with children then go ahead and add in the bottom margin.
1467 if (!marginInfo.discardMargin() && (!marginInfo.canCollapseWithMarginAfter() && !marginInfo.canCollapseWithMarginBefore()
1468 && (!document().inQuirksMode() || !marginInfo.quirkContainer() || !marginInfo.hasMarginAfterQuirk())))
1469 setLogicalHeight(logicalHeight() + marginInfo.margin());
1471 // Now add in our bottom border/padding.
1472 setLogicalHeight(logicalHeight() + afterSide);
1474 // Negative margins can cause our height to shrink below our minimal height (border/padding).
1475 // If this happens, ensure that the computed height is increased to the minimal height.
1476 setLogicalHeight(max(logicalHeight(), beforeSide + afterSide));
1478 // Update our bottom collapsed margin info.
1479 setCollapsedBottomMargin(marginInfo);
1482 void RenderBlockFlow::setMustDiscardMarginBefore(bool value)
1484 if (style()->marginBeforeCollapse() == MDISCARD) {
1489 if (!m_rareData && !value)
1493 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
1495 m_rareData->m_discardMarginBefore = value;
1498 void RenderBlockFlow::setMustDiscardMarginAfter(bool value)
1500 if (style()->marginAfterCollapse() == MDISCARD) {
1505 if (!m_rareData && !value)
1509 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
1511 m_rareData->m_discardMarginAfter = value;
1514 bool RenderBlockFlow::mustDiscardMarginBefore() const
1516 return style()->marginBeforeCollapse() == MDISCARD || (m_rareData && m_rareData->m_discardMarginBefore);
1519 bool RenderBlockFlow::mustDiscardMarginAfter() const
1521 return style()->marginAfterCollapse() == MDISCARD || (m_rareData && m_rareData->m_discardMarginAfter);
1524 bool RenderBlockFlow::mustDiscardMarginBeforeForChild(const RenderBox* child) const
1526 ASSERT(!child->selfNeedsLayout());
1527 if (!child->isWritingModeRoot())
1528 return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginBefore() : (child->style()->marginBeforeCollapse() == MDISCARD);
1529 if (child->isHorizontalWritingMode() == isHorizontalWritingMode())
1530 return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginAfter() : (child->style()->marginAfterCollapse() == MDISCARD);
1532 // FIXME: We return false here because the implementation is not geometrically complete. We have values only for before/after, not start/end.
1533 // In case the boxes are perpendicular we assume the property is not specified.
1537 bool RenderBlockFlow::mustDiscardMarginAfterForChild(const RenderBox* child) const
1539 ASSERT(!child->selfNeedsLayout());
1540 if (!child->isWritingModeRoot())
1541 return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginAfter() : (child->style()->marginAfterCollapse() == MDISCARD);
1542 if (child->isHorizontalWritingMode() == isHorizontalWritingMode())
1543 return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginBefore() : (child->style()->marginBeforeCollapse() == MDISCARD);
1545 // FIXME: See |mustDiscardMarginBeforeForChild| above.
1549 void RenderBlockFlow::setMaxMarginBeforeValues(LayoutUnit pos, LayoutUnit neg)
1552 if (pos == RenderBlockFlowRareData::positiveMarginBeforeDefault(this) && neg == RenderBlockFlowRareData::negativeMarginBeforeDefault(this))
1554 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
1556 m_rareData->m_margins.setPositiveMarginBefore(pos);
1557 m_rareData->m_margins.setNegativeMarginBefore(neg);
1560 void RenderBlockFlow::setMaxMarginAfterValues(LayoutUnit pos, LayoutUnit neg)
1563 if (pos == RenderBlockFlowRareData::positiveMarginAfterDefault(this) && neg == RenderBlockFlowRareData::negativeMarginAfterDefault(this))
1565 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
1567 m_rareData->m_margins.setPositiveMarginAfter(pos);
1568 m_rareData->m_margins.setNegativeMarginAfter(neg);
1571 bool RenderBlockFlow::mustSeparateMarginBeforeForChild(const RenderBox* child) const
1573 ASSERT(!child->selfNeedsLayout());
1574 const RenderStyle* childStyle = child->style();
1575 if (!child->isWritingModeRoot())
1576 return childStyle->marginBeforeCollapse() == MSEPARATE;
1577 if (child->isHorizontalWritingMode() == isHorizontalWritingMode())
1578 return childStyle->marginAfterCollapse() == MSEPARATE;
1580 // FIXME: See |mustDiscardMarginBeforeForChild| above.
1584 bool RenderBlockFlow::mustSeparateMarginAfterForChild(const RenderBox* child) const
1586 ASSERT(!child->selfNeedsLayout());
1587 const RenderStyle* childStyle = child->style();
1588 if (!child->isWritingModeRoot())
1589 return childStyle->marginAfterCollapse() == MSEPARATE;
1590 if (child->isHorizontalWritingMode() == isHorizontalWritingMode())
1591 return childStyle->marginBeforeCollapse() == MSEPARATE;
1593 // FIXME: See |mustDiscardMarginBeforeForChild| above.
1597 LayoutUnit RenderBlockFlow::applyBeforeBreak(RenderBox* child, LayoutUnit logicalOffset)
1599 // FIXME: Add page break checking here when we support printing.
1600 RenderFlowThread* flowThread = flowThreadContainingBlock();
1601 bool isInsideMulticolFlowThread = flowThread;
1602 bool checkColumnBreaks = isInsideMulticolFlowThread || view()->layoutState()->isPaginatingColumns();
1603 bool checkPageBreaks = !checkColumnBreaks && view()->layoutState()->pageLogicalHeight(); // FIXME: Once columns can print we have to check this.
1604 bool checkBeforeAlways = (checkColumnBreaks && child->style()->columnBreakBefore() == PBALWAYS)
1605 || (checkPageBreaks && child->style()->pageBreakBefore() == PBALWAYS);
1606 if (checkBeforeAlways && inNormalFlow(child)) {
1607 if (checkColumnBreaks) {
1608 if (isInsideMulticolFlowThread) {
1609 LayoutUnit offsetBreakAdjustment = 0;
1610 if (flowThread->addForcedRegionBreak(offsetFromLogicalTopOfFirstPage() + logicalOffset, child, true, &offsetBreakAdjustment))
1611 return logicalOffset + offsetBreakAdjustment;
1613 view()->layoutState()->addForcedColumnBreak(*child, logicalOffset);
1616 return nextPageLogicalTop(logicalOffset, IncludePageBoundary);
1618 return logicalOffset;
1621 LayoutUnit RenderBlockFlow::applyAfterBreak(RenderBox* child, LayoutUnit logicalOffset, MarginInfo& marginInfo)
1623 // FIXME: Add page break checking here when we support printing.
1624 RenderFlowThread* flowThread = flowThreadContainingBlock();
1625 bool isInsideMulticolFlowThread = flowThread;
1626 bool checkColumnBreaks = isInsideMulticolFlowThread || view()->layoutState()->isPaginatingColumns();
1627 bool checkPageBreaks = !checkColumnBreaks && view()->layoutState()->pageLogicalHeight(); // FIXME: Once columns can print we have to check this.
1628 bool checkAfterAlways = (checkColumnBreaks && child->style()->columnBreakAfter() == PBALWAYS)
1629 || (checkPageBreaks && child->style()->pageBreakAfter() == PBALWAYS);
1630 if (checkAfterAlways && inNormalFlow(child)) {
1631 LayoutUnit marginOffset = marginInfo.canCollapseWithMarginBefore() ? LayoutUnit() : marginInfo.margin();
1633 // So our margin doesn't participate in the next collapsing steps.
1634 marginInfo.clearMargin();
1636 if (checkColumnBreaks) {
1637 if (isInsideMulticolFlowThread) {
1638 LayoutUnit offsetBreakAdjustment = 0;
1639 if (flowThread->addForcedRegionBreak(offsetFromLogicalTopOfFirstPage() + logicalOffset + marginOffset, child, false, &offsetBreakAdjustment))
1640 return logicalOffset + marginOffset + offsetBreakAdjustment;
1642 view()->layoutState()->addForcedColumnBreak(*child, logicalOffset);
1645 return nextPageLogicalTop(logicalOffset, IncludePageBoundary);
1647 return logicalOffset;
1650 void RenderBlockFlow::addOverflowFromFloats()
1652 if (!m_floatingObjects)
1655 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1656 FloatingObjectSetIterator end = floatingObjectSet.end();
1657 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1658 FloatingObject* floatingObject = it->get();
1659 if (floatingObject->isDescendant())
1660 addOverflowFromChild(floatingObject->renderer(), IntSize(xPositionForFloatIncludingMargin(floatingObject), yPositionForFloatIncludingMargin(floatingObject)));
1664 void RenderBlockFlow::computeOverflow(LayoutUnit oldClientAfterEdge, bool recomputeFloats)
1666 RenderBlock::computeOverflow(oldClientAfterEdge, recomputeFloats);
1667 if (!hasColumns() && (recomputeFloats || createsBlockFormattingContext() || hasSelfPaintingLayer()))
1668 addOverflowFromFloats();
1671 RootInlineBox* RenderBlockFlow::createAndAppendRootInlineBox()
1673 RootInlineBox* rootBox = createRootInlineBox();
1674 m_lineBoxes.appendLineBox(rootBox);
1676 if (UNLIKELY(AXObjectCache::accessibilityEnabled()) && m_lineBoxes.firstLineBox() == rootBox) {
1677 if (AXObjectCache* cache = document().existingAXObjectCache())
1678 cache->recomputeIsIgnored(this);
1684 void RenderBlockFlow::deleteLineBoxTree()
1686 if (containsFloats())
1687 m_floatingObjects->clearLineBoxTreePointers();
1688 RenderBlock::deleteLineBoxTree();
1691 void RenderBlockFlow::markAllDescendantsWithFloatsForLayout(RenderBox* floatToRemove, bool inLayout)
1693 if (!everHadLayout() && !containsFloats())
1696 MarkingBehavior markParents = inLayout ? MarkOnlyThis : MarkContainingBlockChain;
1697 setChildNeedsLayout(markParents);
1700 removeFloatingObject(floatToRemove);
1702 // Iterate over our children and mark them as needed.
1703 if (!childrenInline()) {
1704 for (RenderObject* child = firstChild(); child; child = child->nextSibling()) {
1705 if ((!floatToRemove && child->isFloatingOrOutOfFlowPositioned()) || !child->isRenderBlock())
1707 if (!child->isRenderBlockFlow()) {
1708 RenderBlock* childBlock = toRenderBlock(child);
1709 if (childBlock->shrinkToAvoidFloats() && childBlock->everHadLayout())
1710 childBlock->setChildNeedsLayout(markParents);
1713 RenderBlockFlow* childBlockFlow = toRenderBlockFlow(child);
1714 if ((floatToRemove ? childBlockFlow->containsFloat(floatToRemove) : childBlockFlow->containsFloats()) || childBlockFlow->shrinkToAvoidFloats())
1715 childBlockFlow->markAllDescendantsWithFloatsForLayout(floatToRemove, inLayout);
1720 void RenderBlockFlow::markSiblingsWithFloatsForLayout(RenderBox* floatToRemove)
1722 if (!m_floatingObjects)
1725 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1726 FloatingObjectSetIterator end = floatingObjectSet.end();
1728 for (RenderObject* next = nextSibling(); next; next = next->nextSibling()) {
1729 if (!next->isRenderBlockFlow() || avoidsOrIgnoresFloats())
1732 RenderBlockFlow* nextBlock = toRenderBlockFlow(next);
1733 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1734 RenderBox* floatingBox = (*it)->renderer();
1735 if (floatToRemove && floatingBox != floatToRemove)
1737 if (nextBlock->containsFloat(floatingBox))
1738 nextBlock->markAllDescendantsWithFloatsForLayout(floatingBox);
1743 LayoutUnit RenderBlockFlow::getClearDelta(RenderBox* child, LayoutUnit logicalTop)
1745 // There is no need to compute clearance if we have no floats.
1746 if (!containsFloats())
1749 // At least one float is present. We need to perform the clearance computation.
1750 bool clearSet = child->style()->clear() != CNONE;
1751 LayoutUnit logicalBottom = 0;
1752 switch (child->style()->clear()) {
1756 logicalBottom = lowestFloatLogicalBottom(FloatingObject::FloatLeft);
1759 logicalBottom = lowestFloatLogicalBottom(FloatingObject::FloatRight);
1762 logicalBottom = lowestFloatLogicalBottom();
1766 // We also clear floats if we are too big to sit on the same line as a float (and wish to avoid floats by default).
1767 LayoutUnit result = clearSet ? max<LayoutUnit>(0, logicalBottom - logicalTop) : LayoutUnit();
1768 if (!result && child->avoidsFloats()) {
1769 LayoutUnit newLogicalTop = logicalTop;
1771 LayoutUnit availableLogicalWidthAtNewLogicalTopOffset = availableLogicalWidthForLine(newLogicalTop, false, logicalHeightForChild(child));
1772 if (availableLogicalWidthAtNewLogicalTopOffset == availableLogicalWidthForContent())
1773 return newLogicalTop - logicalTop;
1775 LayoutRect borderBox = child->borderBoxRect();
1776 LayoutUnit childLogicalWidthAtOldLogicalTopOffset = isHorizontalWritingMode() ? borderBox.width() : borderBox.height();
1778 // FIXME: None of this is right for perpendicular writing-mode children.
1779 LayoutUnit childOldLogicalWidth = child->logicalWidth();
1780 LayoutUnit childOldMarginLeft = child->marginLeft();
1781 LayoutUnit childOldMarginRight = child->marginRight();
1782 LayoutUnit childOldLogicalTop = child->logicalTop();
1784 child->setLogicalTop(newLogicalTop);
1785 child->updateLogicalWidth();
1786 borderBox = child->borderBoxRect();
1787 LayoutUnit childLogicalWidthAtNewLogicalTopOffset = isHorizontalWritingMode() ? borderBox.width() : borderBox.height();
1789 child->setLogicalTop(childOldLogicalTop);
1790 child->setLogicalWidth(childOldLogicalWidth);
1791 child->setMarginLeft(childOldMarginLeft);
1792 child->setMarginRight(childOldMarginRight);
1794 if (childLogicalWidthAtNewLogicalTopOffset <= availableLogicalWidthAtNewLogicalTopOffset) {
1795 // Even though we may not be moving, if the logical width did shrink because of the presence of new floats, then
1796 // we need to force a relayout as though we shifted. This happens because of the dynamic addition of overhanging floats
1797 // from previous siblings when negative margins exist on a child (see the addOverhangingFloats call at the end of collapseMargins).
1798 if (childLogicalWidthAtOldLogicalTopOffset != childLogicalWidthAtNewLogicalTopOffset)
1799 child->setChildNeedsLayout(MarkOnlyThis);
1800 return newLogicalTop - logicalTop;
1803 newLogicalTop = nextFloatLogicalBottomBelow(newLogicalTop);
1804 ASSERT(newLogicalTop >= logicalTop);
1805 if (newLogicalTop < logicalTop)
1808 ASSERT_NOT_REACHED();
1813 void RenderBlockFlow::createFloatingObjects()
1815 m_floatingObjects = adoptPtr(new FloatingObjects(this, isHorizontalWritingMode()));
1818 void RenderBlockFlow::styleWillChange(StyleDifference diff, const RenderStyle& newStyle)
1820 RenderStyle* oldStyle = style();
1821 s_canPropagateFloatIntoSibling = oldStyle ? !createsBlockFormattingContext() : false;
1822 if (oldStyle && parent() && diff.needsFullLayout() && oldStyle->position() != newStyle.position()
1823 && containsFloats() && !isFloating() && !isOutOfFlowPositioned() && newStyle.hasOutOfFlowPosition())
1824 markAllDescendantsWithFloatsForLayout();
1826 RenderBlock::styleWillChange(diff, newStyle);
1829 void RenderBlockFlow::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
1831 RenderBlock::styleDidChange(diff, oldStyle);
1833 // After our style changed, if we lose our ability to propagate floats into next sibling
1834 // blocks, then we need to find the top most parent containing that overhanging float and
1835 // then mark its descendants with floats for layout and clear all floats from its next
1836 // sibling blocks that exist in our floating objects list. See bug 56299 and 62875.
1837 bool canPropagateFloatIntoSibling = !avoidsOrIgnoresFloats();
1838 if (diff.needsFullLayout() && s_canPropagateFloatIntoSibling && !canPropagateFloatIntoSibling && hasOverhangingFloats()) {
1839 RenderBlockFlow* parentBlockFlow = this;
1840 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1841 FloatingObjectSetIterator end = floatingObjectSet.end();
1843 for (RenderObject* curr = parent(); curr && !curr->isRenderView(); curr = curr->parent()) {
1844 if (curr->isRenderBlockFlow()) {
1845 RenderBlockFlow* currBlock = toRenderBlockFlow(curr);
1847 if (currBlock->hasOverhangingFloats()) {
1848 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1849 RenderBox* renderer = (*it)->renderer();
1850 if (currBlock->hasOverhangingFloat(renderer)) {
1851 parentBlockFlow = currBlock;
1859 parentBlockFlow->markAllDescendantsWithFloatsForLayout();
1860 parentBlockFlow->markSiblingsWithFloatsForLayout();
1863 if (diff.needsFullLayout() || !oldStyle)
1864 createOrDestroyMultiColumnFlowThreadIfNeeded();
1867 void RenderBlockFlow::updateStaticInlinePositionForChild(RenderBox* child, LayoutUnit logicalTop)
1869 if (child->style()->isOriginalDisplayInlineType())
1870 setStaticInlinePositionForChild(child, logicalTop, startAlignedOffsetForLine(logicalTop, false));
1872 setStaticInlinePositionForChild(child, logicalTop, startOffsetForContent());
1875 void RenderBlockFlow::setStaticInlinePositionForChild(RenderBox* child, LayoutUnit blockOffset, LayoutUnit inlinePosition)
1877 child->layer()->setStaticInlinePosition(inlinePosition);
1880 void RenderBlockFlow::addChild(RenderObject* newChild, RenderObject* beforeChild)
1882 if (RenderMultiColumnFlowThread* flowThread = multiColumnFlowThread()) {
1883 flowThread->addChild(newChild, beforeChild);
1886 RenderBlock::addChild(newChild, beforeChild);
1889 void RenderBlockFlow::moveAllChildrenIncludingFloatsTo(RenderBlock* toBlock, bool fullRemoveInsert)
1891 RenderBlockFlow* toBlockFlow = toRenderBlockFlow(toBlock);
1892 moveAllChildrenTo(toBlockFlow, fullRemoveInsert);
1894 // When a portion of the render tree is being detached, anonymous blocks
1895 // will be combined as their children are deleted. In this process, the
1896 // anonymous block later in the tree is merged into the one preceeding it.
1897 // It can happen that the later block (this) contains floats that the
1898 // previous block (toBlockFlow) did not contain, and thus are not in the
1899 // floating objects list for toBlockFlow. This can result in toBlockFlow containing
1900 // floats that are not in it's floating objects list, but are in the
1901 // floating objects lists of siblings and parents. This can cause problems
1902 // when the float itself is deleted, since the deletion code assumes that
1903 // if a float is not in it's containing block's floating objects list, it
1904 // isn't in any floating objects list. In order to preserve this condition
1905 // (removing it has serious performance implications), we need to copy the
1906 // floating objects from the old block (this) to the new block (toBlockFlow).
1907 // The float's metrics will likely all be wrong, but since toBlockFlow is
1908 // already marked for layout, this will get fixed before anything gets
1910 // See bug https://code.google.com/p/chromium/issues/detail?id=230907
1911 if (m_floatingObjects) {
1912 if (!toBlockFlow->m_floatingObjects)
1913 toBlockFlow->createFloatingObjects();
1915 const FloatingObjectSet& fromFloatingObjectSet = m_floatingObjects->set();
1916 FloatingObjectSetIterator end = fromFloatingObjectSet.end();
1918 for (FloatingObjectSetIterator it = fromFloatingObjectSet.begin(); it != end; ++it) {
1919 FloatingObject* floatingObject = it->get();
1921 // Don't insert the object again if it's already in the list
1922 if (toBlockFlow->containsFloat(floatingObject->renderer()))
1925 toBlockFlow->m_floatingObjects->add(floatingObject->unsafeClone());
1931 void RenderBlockFlow::repaintOverhangingFloats(bool paintAllDescendants)
1933 // Repaint any overhanging floats (if we know we're the one to paint them).
1934 // Otherwise, bail out.
1935 if (!hasOverhangingFloats())
1938 // FIXME: Avoid disabling LayoutState. At the very least, don't disable it for floats originating
1939 // in this block. Better yet would be to push extra state for the containers of other floats.
1940 ForceHorriblySlowRectMapping slowRectMapping(*this);
1941 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1942 FloatingObjectSetIterator end = floatingObjectSet.end();
1943 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1944 FloatingObject* floatingObject = it->get();
1945 // Only repaint the object if it is overhanging, is not in its own layer, and
1946 // is our responsibility to paint (m_shouldPaint is set). When paintAllDescendants is true, the latter
1947 // condition is replaced with being a descendant of us.
1948 if (logicalBottomForFloat(floatingObject) > logicalHeight()
1949 && !floatingObject->renderer()->hasSelfPaintingLayer()
1950 && (floatingObject->shouldPaint() || (paintAllDescendants && floatingObject->renderer()->isDescendantOf(this)))) {
1952 RenderBox* floatingRenderer = floatingObject->renderer();
1953 if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
1954 floatingRenderer->setShouldDoFullPaintInvalidationAfterLayout(true);
1956 floatingRenderer->paintInvalidationForWholeRenderer();
1958 floatingRenderer->repaintOverhangingFloats(false);
1963 void RenderBlockFlow::invalidatePaintForOverflow()
1965 // FIXME: We could tighten up the left and right invalidation points if we let layoutInlineChildren fill them in based off the particular lines
1966 // it had to lay out. We wouldn't need the hasOverflowClip() hack in that case either.
1967 LayoutUnit repaintLogicalLeft = logicalLeftVisualOverflow();
1968 LayoutUnit repaintLogicalRight = logicalRightVisualOverflow();
1969 if (hasOverflowClip()) {
1970 // If we have clipped overflow, we should use layout overflow as well, since visual overflow from lines didn't propagate to our block's overflow.
1971 // Note the old code did this as well but even for overflow:visible. The addition of hasOverflowClip() at least tightens up the hack a bit.
1972 // layoutInlineChildren should be patched to compute the entire repaint rect.
1973 repaintLogicalLeft = min(repaintLogicalLeft, logicalLeftLayoutOverflow());
1974 repaintLogicalRight = max(repaintLogicalRight, logicalRightLayoutOverflow());
1977 LayoutRect repaintRect;
1978 if (isHorizontalWritingMode())
1979 repaintRect = LayoutRect(repaintLogicalLeft, m_repaintLogicalTop, repaintLogicalRight - repaintLogicalLeft, m_repaintLogicalBottom - m_repaintLogicalTop);
1981 repaintRect = LayoutRect(m_repaintLogicalTop, repaintLogicalLeft, m_repaintLogicalBottom - m_repaintLogicalTop, repaintLogicalRight - repaintLogicalLeft);
1983 // The repaint rect may be split across columns, in which case adjustRectForColumns() will return the union.
1984 adjustRectForColumns(repaintRect);
1986 if (hasOverflowClip()) {
1987 // Adjust repaint rect for scroll offset
1988 repaintRect.move(-scrolledContentOffset());
1990 // Don't allow this rect to spill out of our overflow box.
1991 repaintRect.intersect(LayoutRect(LayoutPoint(), size()));
1994 // Make sure the rect is still non-empty after intersecting for overflow above
1995 if (!repaintRect.isEmpty()) {
1996 // Hits in media/event-attributes.html
1997 DisableCompositingQueryAsserts disabler;
1999 invalidatePaintRectangle(repaintRect); // We need to do a partial repaint of our content.
2000 if (hasReflection())
2001 invalidatePaintRectangle(reflectedRect(repaintRect));
2004 m_repaintLogicalTop = 0;
2005 m_repaintLogicalBottom = 0;
2008 void RenderBlockFlow::paintFloats(PaintInfo& paintInfo, const LayoutPoint& paintOffset, bool preservePhase)
2010 if (!m_floatingObjects)
2013 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2014 FloatingObjectSetIterator end = floatingObjectSet.end();
2015 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
2016 FloatingObject* floatingObject = it->get();
2017 // Only paint the object if our m_shouldPaint flag is set.
2018 if (floatingObject->shouldPaint() && !floatingObject->renderer()->hasSelfPaintingLayer()) {
2019 PaintInfo currentPaintInfo(paintInfo);
2020 currentPaintInfo.phase = preservePhase ? paintInfo.phase : PaintPhaseBlockBackground;
2021 // FIXME: LayoutPoint version of xPositionForFloatIncludingMargin would make this much cleaner.
2022 LayoutPoint childPoint = flipFloatForWritingModeForChild(floatingObject, LayoutPoint(paintOffset.x() + xPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->x(), paintOffset.y() + yPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->y()));
2023 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
2024 if (!preservePhase) {
2025 currentPaintInfo.phase = PaintPhaseChildBlockBackgrounds;
2026 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
2027 currentPaintInfo.phase = PaintPhaseFloat;
2028 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
2029 currentPaintInfo.phase = PaintPhaseForeground;
2030 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
2031 currentPaintInfo.phase = PaintPhaseOutline;
2032 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
2038 void RenderBlockFlow::clipOutFloatingObjects(RenderBlock* rootBlock, const PaintInfo* paintInfo, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock)
2040 if (m_floatingObjects) {
2041 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2042 FloatingObjectSetIterator end = floatingObjectSet.end();
2043 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
2044 FloatingObject* floatingObject = it->get();
2045 LayoutRect floatBox(offsetFromRootBlock.width() + xPositionForFloatIncludingMargin(floatingObject),
2046 offsetFromRootBlock.height() + yPositionForFloatIncludingMargin(floatingObject),
2047 floatingObject->renderer()->width(), floatingObject->renderer()->height());
2048 rootBlock->flipForWritingMode(floatBox);
2049 floatBox.move(rootBlockPhysicalPosition.x(), rootBlockPhysicalPosition.y());
2050 paintInfo->context->clipOut(pixelSnappedIntRect(floatBox));
2055 void RenderBlockFlow::clearFloats(EClear clear)
2057 positionNewFloats();
2059 LayoutUnit newY = 0;
2062 newY = lowestFloatLogicalBottom(FloatingObject::FloatLeft);
2065 newY = lowestFloatLogicalBottom(FloatingObject::FloatRight);
2068 newY = lowestFloatLogicalBottom();
2072 if (height() < newY)
2073 setLogicalHeight(newY);
2076 bool RenderBlockFlow::containsFloat(RenderBox* renderer) const
2078 return m_floatingObjects && m_floatingObjects->set().contains<FloatingObjectHashTranslator>(renderer);
2081 void RenderBlockFlow::removeFloatingObjects()
2083 if (!m_floatingObjects)
2086 markSiblingsWithFloatsForLayout();
2088 m_floatingObjects->clear();
2091 LayoutPoint RenderBlockFlow::flipFloatForWritingModeForChild(const FloatingObject* child, const LayoutPoint& point) const
2093 if (!style()->isFlippedBlocksWritingMode())
2096 // This is similar to RenderBox::flipForWritingModeForChild. We have to subtract out our left/top offsets twice, since
2097 // it's going to get added back in. We hide this complication here so that the calling code looks normal for the unflipped
2099 if (isHorizontalWritingMode())
2100 return LayoutPoint(point.x(), point.y() + height() - child->renderer()->height() - 2 * yPositionForFloatIncludingMargin(child));
2101 return LayoutPoint(point.x() + width() - child->renderer()->width() - 2 * xPositionForFloatIncludingMargin(child), point.y());
2104 LayoutUnit RenderBlockFlow::logicalLeftOffsetForPositioningFloat(LayoutUnit logicalTop, LayoutUnit fixedOffset, bool applyTextIndent, LayoutUnit* heightRemaining) const
2106 LayoutUnit offset = fixedOffset;
2107 if (m_floatingObjects && m_floatingObjects->hasLeftObjects())
2108 offset = m_floatingObjects->logicalLeftOffsetForPositioningFloat(fixedOffset, logicalTop, heightRemaining);
2109 return adjustLogicalLeftOffsetForLine(offset, applyTextIndent);
2112 LayoutUnit RenderBlockFlow::logicalRightOffsetForPositioningFloat(LayoutUnit logicalTop, LayoutUnit fixedOffset, bool applyTextIndent, LayoutUnit* heightRemaining) const
2114 LayoutUnit offset = fixedOffset;
2115 if (m_floatingObjects && m_floatingObjects->hasRightObjects())
2116 offset = m_floatingObjects->logicalRightOffsetForPositioningFloat(fixedOffset, logicalTop, heightRemaining);
2117 return adjustLogicalRightOffsetForLine(offset, applyTextIndent);
2120 LayoutUnit RenderBlockFlow::adjustLogicalLeftOffsetForLine(LayoutUnit offsetFromFloats, bool applyTextIndent) const
2122 LayoutUnit left = offsetFromFloats;
2124 if (applyTextIndent && style()->isLeftToRightDirection())
2125 left += textIndentOffset();
2130 LayoutUnit RenderBlockFlow::adjustLogicalRightOffsetForLine(LayoutUnit offsetFromFloats, bool applyTextIndent) const
2132 LayoutUnit right = offsetFromFloats;
2134 if (applyTextIndent && !style()->isLeftToRightDirection())
2135 right -= textIndentOffset();
2140 LayoutPoint RenderBlockFlow::computeLogicalLocationForFloat(const FloatingObject* floatingObject, LayoutUnit logicalTopOffset) const
2142 RenderBox* childBox = floatingObject->renderer();
2143 LayoutUnit logicalLeftOffset = logicalLeftOffsetForContent(); // Constant part of left offset.
2144 LayoutUnit logicalRightOffset; // Constant part of right offset.
2145 logicalRightOffset = logicalRightOffsetForContent();
2147 LayoutUnit floatLogicalWidth = min(logicalWidthForFloat(floatingObject), logicalRightOffset - logicalLeftOffset); // The width we look for.
2149 LayoutUnit floatLogicalLeft;
2151 bool insideFlowThread = flowThreadContainingBlock();
2153 if (childBox->style()->floating() == LeftFloat) {
2154 LayoutUnit heightRemainingLeft = 1;
2155 LayoutUnit heightRemainingRight = 1;
2156 floatLogicalLeft = logicalLeftOffsetForPositioningFloat(logicalTopOffset, logicalLeftOffset, false, &heightRemainingLeft);
2157 while (logicalRightOffsetForPositioningFloat(logicalTopOffset, logicalRightOffset, false, &heightRemainingRight) - floatLogicalLeft < floatLogicalWidth) {
2158 logicalTopOffset += min(heightRemainingLeft, heightRemainingRight);
2159 floatLogicalLeft = logicalLeftOffsetForPositioningFloat(logicalTopOffset, logicalLeftOffset, false, &heightRemainingLeft);
2160 if (insideFlowThread) {
2161 // Have to re-evaluate all of our offsets, since they may have changed.
2162 logicalRightOffset = logicalRightOffsetForContent(); // Constant part of right offset.
2163 logicalLeftOffset = logicalLeftOffsetForContent(); // Constant part of left offset.
2164 floatLogicalWidth = min(logicalWidthForFloat(floatingObject), logicalRightOffset - logicalLeftOffset);
2167 floatLogicalLeft = max(logicalLeftOffset - borderAndPaddingLogicalLeft(), floatLogicalLeft);
2169 LayoutUnit heightRemainingLeft = 1;
2170 LayoutUnit heightRemainingRight = 1;
2171 floatLogicalLeft = logicalRightOffsetForPositioningFloat(logicalTopOffset, logicalRightOffset, false, &heightRemainingRight);
2172 while (floatLogicalLeft - logicalLeftOffsetForPositioningFloat(logicalTopOffset, logicalLeftOffset, false, &heightRemainingLeft) < floatLogicalWidth) {
2173 logicalTopOffset += min(heightRemainingLeft, heightRemainingRight);
2174 floatLogicalLeft = logicalRightOffsetForPositioningFloat(logicalTopOffset, logicalRightOffset, false, &heightRemainingRight);
2175 if (insideFlowThread) {
2176 // Have to re-evaluate all of our offsets, since they may have changed.
2177 logicalRightOffset = logicalRightOffsetForContent(); // Constant part of right offset.
2178 logicalLeftOffset = logicalLeftOffsetForContent(); // Constant part of left offset.
2179 floatLogicalWidth = min(logicalWidthForFloat(floatingObject), logicalRightOffset - logicalLeftOffset);
2182 // Use the original width of the float here, since the local variable
2183 // |floatLogicalWidth| was capped to the available line width. See
2184 // fast/block/float/clamped-right-float.html.
2185 floatLogicalLeft -= logicalWidthForFloat(floatingObject);
2188 return LayoutPoint(floatLogicalLeft, logicalTopOffset);
2191 FloatingObject* RenderBlockFlow::insertFloatingObject(RenderBox* floatBox)
2193 ASSERT(floatBox->isFloating());
2195 // Create the list of special objects if we don't aleady have one
2196 if (!m_floatingObjects) {
2197 createFloatingObjects();
2199 // Don't insert the object again if it's already in the list
2200 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2201 FloatingObjectSetIterator it = floatingObjectSet.find<FloatingObjectHashTranslator>(floatBox);
2202 if (it != floatingObjectSet.end())
2206 // Create the special object entry & append it to the list
2208 OwnPtr<FloatingObject> newObj = FloatingObject::create(floatBox);
2210 // Our location is irrelevant if we're unsplittable or no pagination is in effect.
2211 // Just go ahead and lay out the float.
2212 bool isChildRenderBlock = floatBox->isRenderBlock();
2213 if (isChildRenderBlock && !floatBox->needsLayout() && view()->layoutState()->pageLogicalHeightChanged())
2214 floatBox->setChildNeedsLayout(MarkOnlyThis);
2216 bool needsBlockDirectionLocationSetBeforeLayout = isChildRenderBlock && view()->layoutState()->needsBlockDirectionLocationSetBeforeLayout();
2217 if (!needsBlockDirectionLocationSetBeforeLayout || isWritingModeRoot()) { // We are unsplittable if we're a block flow root.
2218 floatBox->layoutIfNeeded();
2220 floatBox->updateLogicalWidth();
2221 floatBox->computeAndSetBlockDirectionMargins(this);
2224 setLogicalWidthForFloat(newObj.get(), logicalWidthForChild(floatBox) + marginStartForChild(floatBox) + marginEndForChild(floatBox));
2226 return m_floatingObjects->add(newObj.release());
2229 void RenderBlockFlow::removeFloatingObject(RenderBox* floatBox)
2231 if (m_floatingObjects) {
2232 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2233 FloatingObjectSetIterator it = floatingObjectSet.find<FloatingObjectHashTranslator>(floatBox);
2234 if (it != floatingObjectSet.end()) {
2235 FloatingObject* floatingObject = it->get();
2236 if (childrenInline()) {
2237 LayoutUnit logicalTop = logicalTopForFloat(floatingObject);
2238 LayoutUnit logicalBottom = logicalBottomForFloat(floatingObject);
2240 // Fix for https://bugs.webkit.org/show_bug.cgi?id=54995.
2241 if (logicalBottom < 0 || logicalBottom < logicalTop || logicalTop == LayoutUnit::max()) {
2242 logicalBottom = LayoutUnit::max();
2244 // Special-case zero- and less-than-zero-height floats: those don't touch
2245 // the line that they're on, but it still needs to be dirtied. This is
2246 // accomplished by pretending they have a height of 1.
2247 logicalBottom = max(logicalBottom, logicalTop + 1);
2249 if (floatingObject->originatingLine()) {
2250 if (!selfNeedsLayout()) {
2251 ASSERT(floatingObject->originatingLine()->renderer() == this);
2252 floatingObject->originatingLine()->markDirty();
2255 floatingObject->setOriginatingLine(0);
2258 markLinesDirtyInBlockRange(0, logicalBottom);
2260 m_floatingObjects->remove(floatingObject);
2265 void RenderBlockFlow::removeFloatingObjectsBelow(FloatingObject* lastFloat, int logicalOffset)
2267 if (!containsFloats())
2270 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2271 FloatingObject* curr = floatingObjectSet.last().get();
2272 while (curr != lastFloat && (!curr->isPlaced() || logicalTopForFloat(curr) >= logicalOffset)) {
2273 m_floatingObjects->remove(curr);
2274 if (floatingObjectSet.isEmpty())
2276 curr = floatingObjectSet.last().get();
2280 bool RenderBlockFlow::positionNewFloats()
2282 if (!m_floatingObjects)
2285 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2286 if (floatingObjectSet.isEmpty())
2289 // If all floats have already been positioned, then we have no work to do.
2290 if (floatingObjectSet.last()->isPlaced())
2293 // Move backwards through our floating object list until we find a float that has
2294 // already been positioned. Then we'll be able to move forward, positioning all of
2295 // the new floats that need it.
2296 FloatingObjectSetIterator it = floatingObjectSet.end();
2297 --it; // Go to last item.
2298 FloatingObjectSetIterator begin = floatingObjectSet.begin();
2299 FloatingObject* lastPlacedFloatingObject = 0;
2300 while (it != begin) {
2302 if ((*it)->isPlaced()) {
2303 lastPlacedFloatingObject = it->get();
2309 LayoutUnit logicalTop = logicalHeight();
2311 // The float cannot start above the top position of the last positioned float.
2312 if (lastPlacedFloatingObject)
2313 logicalTop = max(logicalTopForFloat(lastPlacedFloatingObject), logicalTop);
2315 FloatingObjectSetIterator end = floatingObjectSet.end();
2316 // Now walk through the set of unpositioned floats and place them.
2317 for (; it != end; ++it) {
2318 FloatingObject* floatingObject = it->get();
2319 // The containing block is responsible for positioning floats, so if we have floats in our
2320 // list that come from somewhere else, do not attempt to position them.
2321 if (floatingObject->renderer()->containingBlock() != this)
2324 RenderBox* childBox = floatingObject->renderer();
2326 // FIXME Investigate if this can be removed. crbug.com/370006
2327 childBox->setMayNeedPaintInvalidation(true);
2329 LayoutUnit childLogicalLeftMargin = style()->isLeftToRightDirection() ? marginStartForChild(childBox) : marginEndForChild(childBox);
2330 LayoutRect oldRect = childBox->frameRect();
2332 if (childBox->style()->clear() & CLEFT)
2333 logicalTop = max(lowestFloatLogicalBottom(FloatingObject::FloatLeft), logicalTop);
2334 if (childBox->style()->clear() & CRIGHT)
2335 logicalTop = max(lowestFloatLogicalBottom(FloatingObject::FloatRight), logicalTop);
2337 LayoutPoint floatLogicalLocation = computeLogicalLocationForFloat(floatingObject, logicalTop);
2339 setLogicalLeftForFloat(floatingObject, floatLogicalLocation.x());
2341 setLogicalLeftForChild(childBox, floatLogicalLocation.x() + childLogicalLeftMargin);
2342 setLogicalTopForChild(childBox, floatLogicalLocation.y() + marginBeforeForChild(childBox));
2344 SubtreeLayoutScope layoutScope(*childBox);
2345 LayoutState* layoutState = view()->layoutState();
2346 bool isPaginated = layoutState->isPaginated();
2347 if (isPaginated && !childBox->needsLayout())
2348 childBox->markForPaginationRelayoutIfNeeded(layoutScope);
2350 childBox->layoutIfNeeded();
2353 // If we are unsplittable and don't fit, then we need to move down.
2354 // We include our margins as part of the unsplittable area.
2355 LayoutUnit newLogicalTop = adjustForUnsplittableChild(childBox, floatLogicalLocation.y(), true);
2357 // See if we have a pagination strut that is making us move down further.
2358 // Note that an unsplittable child can't also have a pagination strut, so this is
2359 // exclusive with the case above.
2360 RenderBlock* childBlock = childBox->isRenderBlock() ? toRenderBlock(childBox) : 0;
2361 if (childBlock && childBlock->paginationStrut()) {
2362 newLogicalTop += childBlock->paginationStrut();
2363 childBlock->setPaginationStrut(0);
2366 if (newLogicalTop != floatLogicalLocation.y()) {
2367 floatingObject->setPaginationStrut(newLogicalTop - floatLogicalLocation.y());
2369 floatLogicalLocation = computeLogicalLocationForFloat(floatingObject, newLogicalTop);
2370 setLogicalLeftForFloat(floatingObject, floatLogicalLocation.x());
2372 setLogicalLeftForChild(childBox, floatLogicalLocation.x() + childLogicalLeftMargin);
2373 setLogicalTopForChild(childBox, floatLogicalLocation.y() + marginBeforeForChild(childBox));
2376 childBlock->setChildNeedsLayout(MarkOnlyThis);
2377 childBox->layoutIfNeeded();
2381 setLogicalTopForFloat(floatingObject, floatLogicalLocation.y());
2383 setLogicalHeightForFloat(floatingObject, logicalHeightForChild(childBox) + marginBeforeForChild(childBox) + marginAfterForChild(childBox));
2385 m_floatingObjects->addPlacedObject(floatingObject);
2387 if (ShapeOutsideInfo* shapeOutside = childBox->shapeOutsideInfo())
2388 shapeOutside->setReferenceBoxLogicalSize(logicalSizeForChild(childBox));
2390 // If the child moved, we have to repaint it.
2391 if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled()
2392 && childBox->checkForPaintInvalidationDuringLayout())
2393 childBox->repaintDuringLayoutIfMoved(oldRect);
2398 bool RenderBlockFlow::hasOverhangingFloat(RenderBox* renderer)
2400 if (!m_floatingObjects || hasColumns() || !parent())
2403 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2404 FloatingObjectSetIterator it = floatingObjectSet.find<FloatingObjectHashTranslator>(renderer);
2405 if (it == floatingObjectSet.end())
2408 return logicalBottomForFloat(it->get()) > logicalHeight();
2411 void RenderBlockFlow::addIntrudingFloats(RenderBlockFlow* prev, LayoutUnit logicalLeftOffset, LayoutUnit logicalTopOffset)
2413 ASSERT(!avoidsFloats());
2415 // If we create our own block formatting context then our contents don't interact with floats outside it, even those from our parent.
2416 if (createsBlockFormattingContext())
2419 // If the parent or previous sibling doesn't have any floats to add, don't bother.
2420 if (!prev->m_floatingObjects)
2423 logicalLeftOffset += marginLogicalLeft();
2425 const FloatingObjectSet& prevSet = prev->m_floatingObjects->set();
2426 FloatingObjectSetIterator prevEnd = prevSet.end();
2427 for (FloatingObjectSetIterator prevIt = prevSet.begin(); prevIt != prevEnd; ++prevIt) {
2428 FloatingObject* floatingObject = prevIt->get();
2429 if (logicalBottomForFloat(floatingObject) > logicalTopOffset) {
2430 if (!m_floatingObjects || !m_floatingObjects->set().contains(floatingObject)) {
2431 // We create the floating object list lazily.
2432 if (!m_floatingObjects)
2433 createFloatingObjects();
2435 // Applying the child's margin makes no sense in the case where the child was passed in.
2436 // since this margin was added already through the modification of the |logicalLeftOffset| variable
2437 // above. |logicalLeftOffset| will equal the margin in this case, so it's already been taken
2438 // into account. Only apply this code if prev is the parent, since otherwise the left margin
2439 // will get applied twice.
2440 LayoutSize offset = isHorizontalWritingMode()
2441 ? LayoutSize(logicalLeftOffset - (prev != parent() ? prev->marginLeft() : LayoutUnit()), logicalTopOffset)
2442 : LayoutSize(logicalTopOffset, logicalLeftOffset - (prev != parent() ? prev->marginTop() : LayoutUnit()));
2444 m_floatingObjects->add(floatingObject->copyToNewContainer(offset));
2450 void RenderBlockFlow::addOverhangingFloats(RenderBlockFlow* child, bool makeChildPaintOtherFloats)
2452 // Prevent floats from being added to the canvas by the root element, e.g., <html>.
2453 if (!child->containsFloats() || child->isRenderRegion() || child->createsBlockFormattingContext())
2456 LayoutUnit childLogicalTop = child->logicalTop();
2457 LayoutUnit childLogicalLeft = child->logicalLeft();
2459 // Floats that will remain the child's responsibility to paint should factor into its
2461 FloatingObjectSetIterator childEnd = child->m_floatingObjects->set().end();
2462 for (FloatingObjectSetIterator childIt = child->m_floatingObjects->set().begin(); childIt != childEnd; ++childIt) {
2463 FloatingObject* floatingObject = childIt->get();
2464 LayoutUnit logicalBottomForFloat = min(this->logicalBottomForFloat(floatingObject), LayoutUnit::max() - childLogicalTop);
2465 LayoutUnit logicalBottom = childLogicalTop + logicalBottomForFloat;
2467 if (logicalBottom > logicalHeight()) {
2468 // If the object is not in the list, we add it now.
2469 if (!containsFloat(floatingObject->renderer())) {
2470 LayoutSize offset = isHorizontalWritingMode() ? LayoutSize(-childLogicalLeft, -childLogicalTop) : LayoutSize(-childLogicalTop, -childLogicalLeft);
2471 bool shouldPaint = false;
2473 // The nearest enclosing layer always paints the float (so that zindex and stacking
2474 // behaves properly). We always want to propagate the desire to paint the float as
2475 // far out as we can, to the outermost block that overlaps the float, stopping only
2476 // if we hit a self-painting layer boundary.
2477 if (floatingObject->renderer()->enclosingFloatPaintingLayer() == enclosingFloatPaintingLayer()) {
2478 floatingObject->setShouldPaint(false);
2481 // We create the floating object list lazily.
2482 if (!m_floatingObjects)
2483 createFloatingObjects();
2485 m_floatingObjects->add(floatingObject->copyToNewContainer(offset, shouldPaint, true));
2488 if (makeChildPaintOtherFloats && !floatingObject->shouldPaint() && !floatingObject->renderer()->hasSelfPaintingLayer()
2489 && floatingObject->renderer()->isDescendantOf(child) && floatingObject->renderer()->enclosingFloatPaintingLayer() == child->enclosingFloatPaintingLayer()) {
2490 // The float is not overhanging from this block, so if it is a descendant of the child, the child should
2491 // paint it (the other case is that it is intruding into the child), unless it has its own layer or enclosing
2493 // If makeChildPaintOtherFloats is false, it means that the child must already know about all the floats
2495 floatingObject->setShouldPaint(true);
2498 // Since the float doesn't overhang, it didn't get put into our list. We need to go ahead and add its overflow in to the
2500 if (floatingObject->isDescendant())
2501 child->addOverflowFromChild(floatingObject->renderer(), LayoutSize(xPositionForFloatIncludingMargin(floatingObject), yPositionForFloatIncludingMargin(floatingObject)));
2506 LayoutUnit RenderBlockFlow::lowestFloatLogicalBottom(FloatingObject::Type floatType) const
2508 if (!m_floatingObjects)
2511 return m_floatingObjects->lowestFloatLogicalBottom(floatType);
2514 LayoutUnit RenderBlockFlow::nextFloatLogicalBottomBelow(LayoutUnit logicalHeight, ShapeOutsideFloatOffsetMode offsetMode) const
2516 if (!m_floatingObjects)
2517 return logicalHeight;
2519 LayoutUnit logicalBottom;
2520 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2521 FloatingObjectSetIterator end = floatingObjectSet.end();
2522 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
2523 FloatingObject* floatingObject = it->get();
2524 LayoutUnit floatLogicalBottom = logicalBottomForFloat(floatingObject);
2525 ShapeOutsideInfo* shapeOutside = floatingObject->renderer()->shapeOutsideInfo();
2526 if (shapeOutside && (offsetMode == ShapeOutsideFloatShapeOffset)) {
2527 LayoutUnit shapeLogicalBottom = logicalTopForFloat(floatingObject) + marginBeforeForChild(floatingObject->renderer()) + shapeOutside->shapeLogicalBottom();
2528 // Use the shapeLogicalBottom unless it extends outside of the margin box, in which case it is clipped.
2529 if (shapeLogicalBottom < floatLogicalBottom)
2530 floatLogicalBottom = shapeLogicalBottom;
2532 if (floatLogicalBottom > logicalHeight)
2533 logicalBottom = logicalBottom ? min(floatLogicalBottom, logicalBottom) : floatLogicalBottom;
2536 return logicalBottom;
2539 bool RenderBlockFlow::hitTestFloats(const HitTestRequest& request, HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset)
2541 if (!m_floatingObjects)
2544 LayoutPoint adjustedLocation = accumulatedOffset;
2545 if (isRenderView()) {
2546 adjustedLocation += toLayoutSize(toRenderView(this)->frameView()->scrollPosition());
2549 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2550 FloatingObjectSetIterator begin = floatingObjectSet.begin();
2551 for (FloatingObjectSetIterator it = floatingObjectSet.end(); it != begin;) {
2553 FloatingObject* floatingObject = it->get();
2554 if (floatingObject->shouldPaint() && !floatingObject->renderer()->hasSelfPaintingLayer()) {
2555 LayoutUnit xOffset = xPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->x();
2556 LayoutUnit yOffset = yPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->y();
2557 LayoutPoint childPoint = flipFloatForWritingModeForChild(floatingObject, adjustedLocation + LayoutSize(xOffset, yOffset));
2558 if (floatingObject->renderer()->hitTest(request, result, locationInContainer, childPoint)) {
2559 updateHitTestResult(result, locationInContainer.point() - toLayoutSize(childPoint));
2568 void RenderBlockFlow::adjustForBorderFit(LayoutUnit x, LayoutUnit& left, LayoutUnit& right) const
2570 RenderBlock::adjustForBorderFit(x, left, right);
2571 if (m_floatingObjects && style()->visibility() == VISIBLE) {
2572 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2573 FloatingObjectSetIterator end = floatingObjectSet.end();
2574 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
2575 FloatingObject* floatingObject = it->get();
2576 // Only examine the object if our m_shouldPaint flag is set.
2577 if (floatingObject->shouldPaint()) {
2578 LayoutUnit floatLeft = xPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->x();
2579 LayoutUnit floatRight = floatLeft + floatingObject->renderer()->width();
2580 left = min(left, floatLeft);
2581 right = max(right, floatRight);
2587 LayoutUnit RenderBlockFlow::logicalLeftFloatOffsetForLine(LayoutUnit logicalTop, LayoutUnit fixedOffset, LayoutUnit logicalHeight) const
2589 if (m_floatingObjects && m_floatingObjects->hasLeftObjects())
2590 return m_floatingObjects->logicalLeftOffset(fixedOffset, logicalTop, logicalHeight);
2595 LayoutUnit RenderBlockFlow::logicalRightFloatOffsetForLine(LayoutUnit logicalTop, LayoutUnit fixedOffset, LayoutUnit logicalHeight) const
2597 if (m_floatingObjects && m_floatingObjects->hasRightObjects())
2598 return m_floatingObjects->logicalRightOffset(fixedOffset, logicalTop, logicalHeight);
2603 GapRects RenderBlockFlow::inlineSelectionGaps(RenderBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock,
2604 LayoutUnit& lastLogicalTop, LayoutUnit& lastLogicalLeft, LayoutUnit& lastLogicalRight, const PaintInfo* paintInfo)
2608 bool containsStart = selectionState() == SelectionStart || selectionState() == SelectionBoth;
2610 if (!firstLineBox()) {
2611 if (containsStart) {
2612 // Go ahead and update our lastLogicalTop to be the bottom of the block. <hr>s or empty blocks with height can trip this
2614 lastLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + logicalHeight();
2615 lastLogicalLeft = logicalLeftSelectionOffset(rootBlock, logicalHeight());
2616 lastLogicalRight = logicalRightSelectionOffset(rootBlock, logicalHeight());
2621 RootInlineBox* lastSelectedLine = 0;
2622 RootInlineBox* curr;
2623 for (curr = firstRootBox(); curr && !curr->hasSelectedChildren(); curr = curr->nextRootBox()) { }
2625 // Now paint the gaps for the lines.
2626 for (; curr && curr->hasSelectedChildren(); curr = curr->nextRootBox()) {
2627 LayoutUnit selTop = curr->selectionTopAdjustedForPrecedingBlock();
2628 LayoutUnit selHeight = curr->selectionHeightAdjustedForPrecedingBlock();
2630 if (!containsStart && !lastSelectedLine && selectionState() != SelectionStart && selectionState() != SelectionBoth) {
2631 result.uniteCenter(blockSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, lastLogicalTop,
2632 lastLogicalLeft, lastLogicalRight, selTop, paintInfo));
2635 LayoutRect logicalRect(curr->logicalLeft(), selTop, curr->logicalWidth(), selTop + selHeight);
2636 logicalRect.move(isHorizontalWritingMode() ? offsetFromRootBlock : offsetFromRootBlock.transposedSize());
2637 LayoutRect physicalRect = rootBlock->logicalRectToPhysicalRect(rootBlockPhysicalPosition, logicalRect);
2638 if (!paintInfo || (isHorizontalWritingMode() && physicalRect.y() < paintInfo->rect.maxY() && physicalRect.maxY() > paintInfo->rect.y())
2639 || (!isHorizontalWritingMode() && physicalRect.x() < paintInfo->rect.maxX() && physicalRect.maxX() > paintInfo->rect.x()))
2640 result.unite(curr->lineSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, selTop, selHeight, paintInfo));
2642 lastSelectedLine = curr;
2645 if (containsStart && !lastSelectedLine) {
2646 // VisibleSelection must start just after our last line.
2647 lastSelectedLine = lastRootBox();
2650 if (lastSelectedLine && selectionState() != SelectionEnd && selectionState() != SelectionBoth) {
2651 // Go ahead and update our lastY to be the bottom of the last selected line.
2652 lastLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + lastSelectedLine->selectionBottom();
2653 lastLogicalLeft = logicalLeftSelectionOffset(rootBlock, lastSelectedLine->selectionBottom());
2654 lastLogicalRight = logicalRightSelectionOffset(rootBlock, lastSelectedLine->selectionBottom());
2659 LayoutUnit RenderBlockFlow::logicalLeftSelectionOffset(RenderBlock* rootBlock, LayoutUnit position)
2661 LayoutUnit logicalLeft = logicalLeftOffsetForLine(position, false);
2662 if (logicalLeft == logicalLeftOffsetForContent())
2663 return RenderBlock::logicalLeftSelectionOffset(rootBlock, position);
2665 RenderBlock* cb = this;
2666 while (cb != rootBlock) {
2667 logicalLeft += cb->logicalLeft();
2668 cb = cb->containingBlock();
2673 LayoutUnit RenderBlockFlow::logicalRightSelectionOffset(RenderBlock* rootBlock, LayoutUnit position)
2675 LayoutUnit logicalRight = logicalRightOffsetForLine(position, false);
2676 if (logicalRight == logicalRightOffsetForContent())
2677 return RenderBlock::logicalRightSelectionOffset(rootBlock, position);
2679 RenderBlock* cb = this;
2680 while (cb != rootBlock) {
2681 logicalRight += cb->logicalLeft();
2682 cb = cb->containingBlock();
2684 return logicalRight;
2687 template <typename CharacterType>
2688 static inline TextRun constructTextRunInternal(RenderObject* context, const Font& font, const CharacterType* characters, int length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2692 TextDirection textDirection = direction;
2693 bool directionalOverride = style->rtlOrdering() == VisualOrder;
2695 TextRun run(characters, length, 0, 0, expansion, textDirection, directionalOverride);
2696 if (textRunNeedsRenderingContext(font))
2697 run.setRenderingContext(SVGTextRunRenderingContext::create(context));
2702 template <typename CharacterType>
2703 static inline TextRun constructTextRunInternal(RenderObject* context, const Font& font, const CharacterType* characters, int length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion, TextRunFlags flags)
2707 TextDirection textDirection = direction;
2708 bool directionalOverride = style->rtlOrdering() == VisualOrder;
2709 if (flags != DefaultTextRunFlags) {
2710 if (flags & RespectDirection)
2711 textDirection = style->direction();
2712 if (flags & RespectDirectionOverride)
2713 directionalOverride |= isOverride(style->unicodeBidi());
2716 TextRun run(characters, length, 0, 0, expansion, textDirection, directionalOverride);
2717 if (textRunNeedsRenderingContext(font))
2718 run.setRenderingContext(SVGTextRunRenderingContext::create(context));
2723 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const LChar* characters, int length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2725 return constructTextRunInternal(context, font, characters, length, style, direction, expansion);
2728 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const UChar* characters, int length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2730 return constructTextRunInternal(context, font, characters, length, style, direction, expansion);
2733 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const RenderText* text, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2736 return constructTextRunInternal(context, font, text->characters8(), text->textLength(), style, direction, expansion);
2737 return constructTextRunInternal(context, font, text->characters16(), text->textLength(), style, direction, expansion);
2740 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const RenderText* text, unsigned offset, unsigned length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2742 ASSERT(offset + length <= text->textLength());
2744 return constructTextRunInternal(context, font, text->characters8() + offset, length, style, direction, expansion);
2745 return constructTextRunInternal(context, font, text->characters16() + offset, length, style, direction, expansion);
2748 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const String& string, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion, TextRunFlags flags)
2750 unsigned length = string.length();
2752 return constructTextRunInternal(context, font, static_cast<const LChar*>(0), length, style, direction, expansion, flags);
2753 if (string.is8Bit())
2754 return constructTextRunInternal(context, font, string.characters8(), length, style, direction, expansion, flags);
2755 return constructTextRunInternal(context, font, string.characters16(), length, style, direction, expansion, flags);
2758 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const String& string, RenderStyle* style, TextRun::ExpansionBehavior expansion, TextRunFlags flags)
2760 bool hasStrongDirectionality;
2761 return constructTextRun(context, font, string, style,
2762 determineDirectionality(string, hasStrongDirectionality),
2766 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const RenderText* text, unsigned offset, unsigned length, RenderStyle* style, TextRun::ExpansionBehavior expansion)
2768 ASSERT(offset + length <= text->textLength());
2769 TextRun run = text->is8Bit()
2770 ? constructTextRunInternal(context, font, text->characters8() + offset, length, style, LTR, expansion)
2771 : constructTextRunInternal(context, font, text->characters16() + offset, length, style, LTR, expansion);
2772 bool hasStrongDirectionality;
2773 run.setDirection(directionForRun(run, hasStrongDirectionality));
2777 RootInlineBox* RenderBlockFlow::createRootInlineBox()
2779 return new RootInlineBox(*this);
2782 void RenderBlockFlow::createOrDestroyMultiColumnFlowThreadIfNeeded()
2784 if (!document().regionBasedColumnsEnabled())
2787 bool needsFlowThread = style()->specifiesColumns();
2788 if (needsFlowThread != static_cast<bool>(multiColumnFlowThread())) {
2789 if (needsFlowThread) {
2790 RenderMultiColumnFlowThread* flowThread = RenderMultiColumnFlowThread::createAnonymous(document(), style());
2791 addChild(flowThread);
2792 flowThread->populate();
2793 RenderBlockFlowRareData& rareData = ensureRareData();
2794 ASSERT(!rareData.m_multiColumnFlowThread);
2795 rareData.m_multiColumnFlowThread = flowThread;
2797 multiColumnFlowThread()->evacuateAndDestroy();
2798 ASSERT(!multiColumnFlowThread());
2803 RenderBlockFlow::RenderBlockFlowRareData& RenderBlockFlow::ensureRareData()
2808 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
2812 } // namespace WebCore