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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/LayoutRectRecorder.h"
39 #include "core/rendering/LayoutRepainter.h"
40 #include "core/rendering/RenderFlowThread.h"
41 #include "core/rendering/RenderLayer.h"
42 #include "core/rendering/RenderMultiColumnBlock.h"
43 #include "core/rendering/RenderText.h"
44 #include "core/rendering/RenderView.h"
45 #include "core/rendering/line/LineWidth.h"
46 #include "core/rendering/svg/SVGTextRunRenderingContext.h"
47 #include "platform/text/BidiTextRun.h"
53 bool RenderBlockFlow::s_canPropagateFloatIntoSibling = false;
55 struct SameSizeAsMarginInfo {
57 LayoutUnit margins[2];
60 COMPILE_ASSERT(sizeof(RenderBlockFlow::MarginValues) == sizeof(LayoutUnit[4]), MarginValues_should_stay_small);
63 // Collapsing flags for whether we can collapse our margins with our children's margins.
64 bool m_canCollapseWithChildren : 1;
65 bool m_canCollapseMarginBeforeWithChildren : 1;
66 bool m_canCollapseMarginAfterWithChildren : 1;
67 bool m_canCollapseMarginAfterWithLastChild: 1;
69 // Whether or not we are a quirky container, i.e., do we collapse away top and bottom
70 // margins in our container. Table cells and the body are the common examples. We
71 // also have a custom style property for Safari RSS to deal with TypePad blog articles.
72 bool m_quirkContainer : 1;
74 // This flag tracks whether we are still looking at child margins that can all collapse together at the beginning of a block.
75 // They may or may not collapse with the top margin of the block (|m_canCollapseTopWithChildren| tells us that), but they will
76 // always be collapsing with one another. This variable can remain set to true through multiple iterations
77 // as long as we keep encountering self-collapsing blocks.
78 bool m_atBeforeSideOfBlock : 1;
80 // This flag is set when we know we're examining bottom margins and we know we're at the bottom of the block.
81 bool m_atAfterSideOfBlock : 1;
83 // These variables are used to detect quirky margins that we need to collapse away (in table cells
84 // and in the body element).
85 bool m_hasMarginBeforeQuirk : 1;
86 bool m_hasMarginAfterQuirk : 1;
87 bool m_determinedMarginBeforeQuirk : 1;
89 bool m_discardMargin : 1;
91 // These flags track the previous maximal positive and negative margins.
92 LayoutUnit m_positiveMargin;
93 LayoutUnit m_negativeMargin;
96 MarginInfo(RenderBlockFlow*, LayoutUnit beforeBorderPadding, LayoutUnit afterBorderPadding);
98 void setAtBeforeSideOfBlock(bool b) { m_atBeforeSideOfBlock = b; }
99 void setAtAfterSideOfBlock(bool b) { m_atAfterSideOfBlock = b; }
102 m_positiveMargin = 0;
103 m_negativeMargin = 0;
105 void setHasMarginBeforeQuirk(bool b) { m_hasMarginBeforeQuirk = b; }
106 void setHasMarginAfterQuirk(bool b) { m_hasMarginAfterQuirk = b; }
107 void setDeterminedMarginBeforeQuirk(bool b) { m_determinedMarginBeforeQuirk = b; }
108 void setPositiveMargin(LayoutUnit p) { ASSERT(!m_discardMargin); m_positiveMargin = p; }
109 void setNegativeMargin(LayoutUnit n) { ASSERT(!m_discardMargin); m_negativeMargin = n; }
110 void setPositiveMarginIfLarger(LayoutUnit p)
112 ASSERT(!m_discardMargin);
113 if (p > m_positiveMargin)
114 m_positiveMargin = p;
116 void setNegativeMarginIfLarger(LayoutUnit n)
118 ASSERT(!m_discardMargin);
119 if (n > m_negativeMargin)
120 m_negativeMargin = n;
123 void setMargin(LayoutUnit p, LayoutUnit n) { ASSERT(!m_discardMargin); m_positiveMargin = p; m_negativeMargin = n; }
124 void setCanCollapseMarginAfterWithChildren(bool collapse) { m_canCollapseMarginAfterWithChildren = collapse; }
125 void setCanCollapseMarginAfterWithLastChild(bool collapse) { m_canCollapseMarginAfterWithLastChild = collapse; }
126 void setDiscardMargin(bool value) { m_discardMargin = value; }
128 bool atBeforeSideOfBlock() const { return m_atBeforeSideOfBlock; }
129 bool canCollapseWithMarginBefore() const { return m_atBeforeSideOfBlock && m_canCollapseMarginBeforeWithChildren; }
130 bool canCollapseWithMarginAfter() const { return m_atAfterSideOfBlock && m_canCollapseMarginAfterWithChildren; }
131 bool canCollapseMarginBeforeWithChildren() const { return m_canCollapseMarginBeforeWithChildren; }
132 bool canCollapseMarginAfterWithChildren() const { return m_canCollapseMarginAfterWithChildren; }
133 bool canCollapseMarginAfterWithLastChild() const { return m_canCollapseMarginAfterWithLastChild; }
134 bool quirkContainer() const { return m_quirkContainer; }
135 bool determinedMarginBeforeQuirk() const { return m_determinedMarginBeforeQuirk; }
136 bool hasMarginBeforeQuirk() const { return m_hasMarginBeforeQuirk; }
137 bool hasMarginAfterQuirk() const { return m_hasMarginAfterQuirk; }
138 LayoutUnit positiveMargin() const { return m_positiveMargin; }
139 LayoutUnit negativeMargin() const { return m_negativeMargin; }
140 bool discardMargin() const { return m_discardMargin; }
141 LayoutUnit margin() const { return m_positiveMargin - m_negativeMargin; }
143 static bool inNormalFlow(RenderBox* child)
145 RenderBlock* curr = child->containingBlock();
146 RenderView* renderView = child->view();
147 while (curr && curr != renderView) {
148 if (curr->hasColumns() || curr->isRenderFlowThread())
150 if (curr->isFloatingOrOutOfFlowPositioned())
152 curr = curr->containingBlock();
157 RenderBlockFlow::RenderBlockFlow(ContainerNode* node)
160 COMPILE_ASSERT(sizeof(MarginInfo) == sizeof(SameSizeAsMarginInfo), MarginInfo_should_stay_small);
163 RenderBlockFlow::~RenderBlockFlow()
167 RenderBlockFlow* RenderBlockFlow::createAnonymous(Document* document)
169 RenderBlockFlow* renderer = new RenderBlockFlow(0);
170 renderer->setDocumentForAnonymous(document);
174 RenderBlockFlow* RenderBlockFlow::createAnonymousBlockFlow() const
176 return toRenderBlockFlow(createAnonymousWithParentRendererAndDisplay(this, BLOCK));
179 void RenderBlockFlow::checkForPaginationLogicalHeightChange(LayoutUnit& pageLogicalHeight, bool& pageLogicalHeightChanged, bool& hasSpecifiedPageLogicalHeight)
181 ColumnInfo* colInfo = columnInfo();
183 if (!pageLogicalHeight) {
184 LayoutUnit oldLogicalHeight = logicalHeight();
186 // We need to go ahead and set our explicit page height if one exists, so that we can
187 // avoid doing two layout passes.
188 updateLogicalHeight();
189 LayoutUnit columnHeight = contentLogicalHeight();
190 if (columnHeight > 0) {
191 pageLogicalHeight = columnHeight;
192 hasSpecifiedPageLogicalHeight = true;
194 setLogicalHeight(oldLogicalHeight);
196 if (colInfo->columnHeight() != pageLogicalHeight && everHadLayout()) {
197 colInfo->setColumnHeight(pageLogicalHeight);
198 pageLogicalHeightChanged = true;
201 if (!hasSpecifiedPageLogicalHeight && !pageLogicalHeight)
202 colInfo->clearForcedBreaks();
203 } else if (isRenderFlowThread()) {
204 pageLogicalHeight = 1; // This is just a hack to always make sure we have a page logical height.
205 pageLogicalHeightChanged = toRenderFlowThread(this)->pageLogicalSizeChanged();
209 bool RenderBlockFlow::shouldRelayoutForPagination(LayoutUnit& pageLogicalHeight, LayoutUnit layoutOverflowLogicalBottom) const
211 // FIXME: We don't balance properly at all in the presence of forced page breaks. We need to understand what
212 // the distance between forced page breaks is so that we can avoid making the minimum column height too tall.
213 ColumnInfo* colInfo = columnInfo();
214 LayoutUnit columnHeight = pageLogicalHeight;
215 const int minColumnCount = colInfo->forcedBreaks() + 1;
216 const int desiredColumnCount = colInfo->desiredColumnCount();
217 if (minColumnCount >= desiredColumnCount) {
218 // The forced page breaks are in control of the balancing. Just set the column height to the
219 // maximum page break distance.
220 if (!pageLogicalHeight) {
221 LayoutUnit distanceBetweenBreaks = max<LayoutUnit>(colInfo->maximumDistanceBetweenForcedBreaks(),
222 view()->layoutState()->pageLogicalOffset(this, borderBefore() + paddingBefore() + layoutOverflowLogicalBottom) - colInfo->forcedBreakOffset());
223 columnHeight = max(colInfo->minimumColumnHeight(), distanceBetweenBreaks);
225 } else if (layoutOverflowLogicalBottom > boundedMultiply(pageLogicalHeight, desiredColumnCount)) {
226 // Now that we know the intrinsic height of the columns, we have to rebalance them.
227 columnHeight = max<LayoutUnit>(colInfo->minimumColumnHeight(), ceilf((float)layoutOverflowLogicalBottom / desiredColumnCount));
230 if (columnHeight && columnHeight != pageLogicalHeight) {
231 pageLogicalHeight = columnHeight;
238 void RenderBlockFlow::setColumnCountAndHeight(unsigned count, LayoutUnit pageLogicalHeight)
240 ColumnInfo* colInfo = columnInfo();
241 if (pageLogicalHeight)
242 colInfo->setColumnCountAndHeight(count, pageLogicalHeight);
244 if (columnCount(colInfo)) {
245 setLogicalHeight(borderBefore() + paddingBefore() + colInfo->columnHeight() + borderAfter() + paddingAfter() + scrollbarLogicalHeight());
250 bool RenderBlockFlow::isSelfCollapsingBlock() const
252 m_hasOnlySelfCollapsingChildren = RenderBlock::isSelfCollapsingBlock();
253 return m_hasOnlySelfCollapsingChildren;
256 void RenderBlockFlow::layoutBlock(bool relayoutChildren)
258 ASSERT(needsLayout());
259 ASSERT(isInlineBlockOrInlineTable() || !isInline());
261 // If we are self-collapsing with self-collapsing descendants this will get set to save us burrowing through our
262 // descendants every time in |isSelfCollapsingBlock|. We reset it here so that |isSelfCollapsingBlock| attempts to burrow
263 // at least once and so that it always gives a reliable result reflecting the latest layout.
264 m_hasOnlySelfCollapsingChildren = false;
266 if (!relayoutChildren && simplifiedLayout())
269 SubtreeLayoutScope layoutScope(this);
271 // Multiple passes might be required for column and pagination based layout
272 // In the case of the old column code the number of passes will only be two
273 // however, in the newer column code the number of passes could equal the
274 // number of columns.
276 LayoutUnit pageLogicalHeight = 0;
278 done = layoutBlockFlow(relayoutChildren, pageLogicalHeight, layoutScope);
281 inline bool RenderBlockFlow::layoutBlockFlow(bool relayoutChildren, LayoutUnit &pageLogicalHeight, SubtreeLayoutScope& layoutScope)
283 LayoutRepainter repainter(*this, checkForRepaintDuringLayout());
285 if (updateLogicalWidthAndColumnWidth())
286 relayoutChildren = true;
288 rebuildFloatsFromIntruding();
290 bool pageLogicalHeightChanged = false;
291 bool hasSpecifiedPageLogicalHeight = false;
292 checkForPaginationLogicalHeightChange(pageLogicalHeight, pageLogicalHeightChanged, hasSpecifiedPageLogicalHeight);
294 RenderView* renderView = view();
295 LayoutStateMaintainer statePusher(renderView, this, locationOffset(), hasColumns() || hasTransform() || hasReflection() || style()->isFlippedBlocksWritingMode(), pageLogicalHeight, pageLogicalHeightChanged, columnInfo());
297 // Regions changing widths can force us to relayout our children.
298 RenderFlowThread* flowThread = flowThreadContainingBlock();
299 if (updateRegionsAndShapesLogicalSize(flowThread))
300 relayoutChildren = true;
302 // We use four values, maxTopPos, maxTopNeg, maxBottomPos, and maxBottomNeg, to track
303 // our current maximal positive and negative margins. These values are used when we
304 // are collapsed with adjacent blocks, so for example, if you have block A and B
305 // collapsing together, then you'd take the maximal positive margin from both A and B
306 // and subtract it from the maximal negative margin from both A and B to get the
307 // true collapsed margin. This algorithm is recursive, so when we finish layout()
308 // our block knows its current maximal positive/negative values.
310 // Start out by setting our margin values to our current margins. Table cells have
311 // no margins, so we don't fill in the values for table cells.
312 if (!isTableCell()) {
313 initMaxMarginValues();
314 setHasMarginBeforeQuirk(style()->hasMarginBeforeQuirk());
315 setHasMarginAfterQuirk(style()->hasMarginAfterQuirk());
316 setPaginationStrut(0);
319 LayoutUnit beforeEdge = borderBefore() + paddingBefore();
320 LayoutUnit afterEdge = borderAfter() + paddingAfter() + scrollbarLogicalHeight();
321 LayoutUnit previousHeight = logicalHeight();
322 setLogicalHeight(beforeEdge);
324 m_repaintLogicalTop = 0;
325 m_repaintLogicalBottom = 0;
326 LayoutUnit maxFloatLogicalBottom = 0;
327 if (!firstChild() && !isAnonymousBlock())
328 setChildrenInline(true);
330 FastTextAutosizer::LayoutScope fastTextAutosizerLayoutScope(document(), this);
332 if (childrenInline())
333 layoutInlineChildren(relayoutChildren, m_repaintLogicalTop, m_repaintLogicalBottom, afterEdge);
335 layoutBlockChildren(relayoutChildren, maxFloatLogicalBottom, layoutScope, beforeEdge, afterEdge);
337 if (frameView()->partialLayout().isStopping()) {
342 // Expand our intrinsic height to encompass floats.
343 if (lowestFloatLogicalBottom() > (logicalHeight() - afterEdge) && createsBlockFormattingContext())
344 setLogicalHeight(lowestFloatLogicalBottom() + afterEdge);
346 if (isRenderMultiColumnBlock()) {
347 if (toRenderMultiColumnBlock(this)->shouldRelayoutMultiColumnBlock()) {
348 setChildNeedsLayout(MarkOnlyThis);
352 } else if (hasColumns()) {
353 OwnPtr<RenderOverflow> savedOverflow = m_overflow.release();
354 if (childrenInline())
355 addOverflowFromInlineChildren();
357 addOverflowFromBlockChildren();
358 LayoutUnit layoutOverflowLogicalBottom = (isHorizontalWritingMode() ? layoutOverflowRect().maxY() : layoutOverflowRect().maxX()) - borderBefore() - paddingBefore();
359 m_overflow = savedOverflow.release();
361 if (!hasSpecifiedPageLogicalHeight && shouldRelayoutForPagination(pageLogicalHeight, layoutOverflowLogicalBottom)) {
363 setEverHadLayout(true);
367 setColumnCountAndHeight(ceilf((float)layoutOverflowLogicalBottom / pageLogicalHeight), pageLogicalHeight);
370 if (shouldBreakAtLineToAvoidWidow()) {
372 setEverHadLayout(true);
376 // Calculate our new height.
377 LayoutUnit oldHeight = logicalHeight();
378 LayoutUnit oldClientAfterEdge = clientLogicalBottom();
380 if (isRenderFlowThread())
381 toRenderFlowThread(this)->applyBreakAfterContent(oldClientAfterEdge);
383 updateLogicalHeight();
384 LayoutUnit newHeight = logicalHeight();
385 if (oldHeight != newHeight) {
386 if (oldHeight > newHeight && maxFloatLogicalBottom > newHeight && !childrenInline()) {
387 // One of our children's floats may have become an overhanging float for us. We need to look for it.
388 for (RenderObject* child = firstChild(); child; child = child->nextSibling()) {
389 if (child->isRenderBlockFlow() && !child->isFloatingOrOutOfFlowPositioned()) {
390 RenderBlockFlow* block = toRenderBlockFlow(child);
391 if (block->lowestFloatLogicalBottom() + block->logicalTop() > newHeight)
392 addOverhangingFloats(block, false);
398 bool heightChanged = (previousHeight != newHeight);
400 relayoutChildren = true;
402 layoutPositionedObjects(relayoutChildren || isRoot());
404 updateRegionsAndShapesAfterChildLayout(flowThread, heightChanged);
406 // Add overflow from children (unless we're multi-column, since in that case all our child overflow is clipped anyway).
407 computeOverflow(oldClientAfterEdge);
411 fitBorderToLinesIfNeeded();
413 if (frameView()->partialLayout().isStopping())
416 if (renderView->layoutState()->m_pageLogicalHeight)
417 setPageLogicalOffset(renderView->layoutState()->pageLogicalOffset(this, logicalTop()));
419 updateLayerTransform();
421 // Update our scroll information if we're overflow:auto/scroll/hidden now that we know if
422 // we overflow or not.
423 updateScrollInfoAfterLayout();
425 // Repaint with our new bounds if they are different from our old bounds.
426 bool didFullRepaint = repainter.repaintAfterLayout();
427 if (!didFullRepaint && m_repaintLogicalTop != m_repaintLogicalBottom && (style()->visibility() == VISIBLE || enclosingLayer()->hasVisibleContent())) {
428 if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
429 setShouldRepaintOverflowIfNeeded(true);
438 void RenderBlockFlow::layoutBlockChild(RenderBox* child, MarginInfo& marginInfo, LayoutUnit& previousFloatLogicalBottom, LayoutUnit& maxFloatLogicalBottom)
440 LayoutUnit oldPosMarginBefore = maxPositiveMarginBefore();
441 LayoutUnit oldNegMarginBefore = maxNegativeMarginBefore();
443 // The child is a normal flow object. Compute the margins we will use for collapsing now.
444 child->computeAndSetBlockDirectionMargins(this);
446 // Try to guess our correct logical top position. In most cases this guess will
447 // be correct. Only if we're wrong (when we compute the real logical top position)
448 // will we have to potentially relayout.
449 LayoutUnit estimateWithoutPagination;
450 LayoutUnit logicalTopEstimate = estimateLogicalTopPosition(child, marginInfo, estimateWithoutPagination);
452 // Cache our old rect so that we can dirty the proper repaint rects if the child moves.
453 LayoutRect oldRect = child->frameRect();
454 LayoutUnit oldLogicalTop = logicalTopForChild(child);
457 LayoutSize oldLayoutDelta = RuntimeEnabledFeatures::repaintAfterLayoutEnabled() ? LayoutSize() : view()->layoutDelta();
459 // Go ahead and position the child as though it didn't collapse with the top.
460 setLogicalTopForChild(child, logicalTopEstimate, ApplyLayoutDelta);
462 RenderBlock* childRenderBlock = child->isRenderBlock() ? toRenderBlock(child) : 0;
463 RenderBlockFlow* childRenderBlockFlow = (childRenderBlock && child->isRenderBlockFlow()) ? toRenderBlockFlow(child) : 0;
464 bool markDescendantsWithFloats = false;
465 if (logicalTopEstimate != oldLogicalTop && !child->avoidsFloats() && childRenderBlock && childRenderBlock->containsFloats()) {
466 markDescendantsWithFloats = true;
467 } else if (UNLIKELY(logicalTopEstimate.mightBeSaturated())) {
468 // logicalTopEstimate, returned by estimateLogicalTopPosition, might be saturated for
469 // very large elements. If it does the comparison with oldLogicalTop might yield a
470 // false negative as adding and removing margins, borders etc from a saturated number
471 // might yield incorrect results. If this is the case always mark for layout.
472 markDescendantsWithFloats = true;
473 } else if (!child->avoidsFloats() || child->shrinkToAvoidFloats()) {
474 // If an element might be affected by the presence of floats, then always mark it for
476 LayoutUnit fb = max(previousFloatLogicalBottom, lowestFloatLogicalBottom());
477 if (fb > logicalTopEstimate)
478 markDescendantsWithFloats = true;
481 if (childRenderBlockFlow) {
482 if (markDescendantsWithFloats)
483 childRenderBlockFlow->markAllDescendantsWithFloatsForLayout();
484 if (!child->isWritingModeRoot())
485 previousFloatLogicalBottom = max(previousFloatLogicalBottom, oldLogicalTop + childRenderBlockFlow->lowestFloatLogicalBottom());
488 SubtreeLayoutScope layoutScope(child);
489 if (!child->needsLayout())
490 child->markForPaginationRelayoutIfNeeded(layoutScope);
492 bool childHadLayout = child->everHadLayout();
493 bool childNeededLayout = child->needsLayout();
494 if (childNeededLayout)
497 if (frameView()->partialLayout().isStopping())
500 // Cache if we are at the top of the block right now.
501 bool atBeforeSideOfBlock = marginInfo.atBeforeSideOfBlock();
502 bool childIsSelfCollapsing = child->isSelfCollapsingBlock();
504 // Now determine the correct ypos based off examination of collapsing margin
506 LayoutUnit logicalTopBeforeClear = collapseMargins(child, marginInfo, childIsSelfCollapsing);
508 // Now check for clear.
509 LayoutUnit logicalTopAfterClear = clearFloatsIfNeeded(child, marginInfo, oldPosMarginBefore, oldNegMarginBefore, logicalTopBeforeClear, childIsSelfCollapsing);
511 bool paginated = view()->layoutState()->isPaginated();
513 logicalTopAfterClear = adjustBlockChildForPagination(logicalTopAfterClear, estimateWithoutPagination, child,
514 atBeforeSideOfBlock && logicalTopBeforeClear == logicalTopAfterClear);
517 setLogicalTopForChild(child, logicalTopAfterClear, ApplyLayoutDelta);
519 // Now we have a final top position. See if it really does end up being different from our estimate.
520 // clearFloatsIfNeeded can also mark the child as needing a layout even though we didn't move. This happens
521 // when collapseMargins dynamically adds overhanging floats because of a child with negative margins.
522 if (logicalTopAfterClear != logicalTopEstimate || child->needsLayout() || (paginated && childRenderBlock && childRenderBlock->shouldBreakAtLineToAvoidWidow())) {
523 SubtreeLayoutScope layoutScope(child);
524 if (child->shrinkToAvoidFloats()) {
525 // The child's width depends on the line width.
526 // When the child shifts to clear an item, its width can
527 // change (because it has more available line width).
528 // So go ahead and mark the item as dirty.
529 layoutScope.setChildNeedsLayout(child);
532 if (childRenderBlock) {
533 if (!child->avoidsFloats() && childRenderBlock->containsFloats())
534 childRenderBlockFlow->markAllDescendantsWithFloatsForLayout();
535 if (!child->needsLayout())
536 child->markForPaginationRelayoutIfNeeded(layoutScope);
539 // Our guess was wrong. Make the child lay itself out again.
540 child->layoutIfNeeded();
543 // If we previously encountered a self-collapsing sibling of this child that had clearance then
544 // we set this bit to ensure we would not collapse the child's margins, and those of any subsequent
545 // self-collapsing siblings, with our parent. If this child is not self-collapsing then it can
546 // collapse its margins with the parent so reset the bit.
547 if (!marginInfo.canCollapseMarginAfterWithLastChild() && !childIsSelfCollapsing)
548 marginInfo.setCanCollapseMarginAfterWithLastChild(true);
550 // We are no longer at the top of the block if we encounter a non-empty child.
551 // This has to be done after checking for clear, so that margins can be reset if a clear occurred.
552 if (marginInfo.atBeforeSideOfBlock() && !childIsSelfCollapsing)
553 marginInfo.setAtBeforeSideOfBlock(false);
555 // Now place the child in the correct left position
556 determineLogicalLeftPositionForChild(child, ApplyLayoutDelta);
558 LayoutSize childOffset = child->location() - oldRect.location();
559 relayoutShapeDescendantIfMoved(childRenderBlock, childOffset);
561 // Update our height now that the child has been placed in the correct position.
562 setLogicalHeight(logicalHeight() + logicalHeightForChild(child));
563 if (mustSeparateMarginAfterForChild(child)) {
564 setLogicalHeight(logicalHeight() + marginAfterForChild(child));
565 marginInfo.clearMargin();
567 // If the child has overhanging floats that intrude into following siblings (or possibly out
568 // of this block), then the parent gets notified of the floats now.
569 if (childRenderBlockFlow && childRenderBlockFlow->containsFloats())
570 maxFloatLogicalBottom = max(maxFloatLogicalBottom, addOverhangingFloats(childRenderBlockFlow, !childNeededLayout));
572 if (childOffset.width() || childOffset.height()) {
573 if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
574 view()->addLayoutDelta(childOffset);
576 // If the child moved, we have to repaint it as well as any floating/positioned
577 // descendants. An exception is if we need a layout. In this case, we know we're going to
578 // repaint ourselves (and the child) anyway.
579 if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled() && childHadLayout && !selfNeedsLayout())
580 child->repaintOverhangingFloats(true);
581 else if (childHadLayout && !selfNeedsLayout() && child->checkForRepaintDuringLayout())
582 child->repaintDuringLayoutIfMoved(oldRect);
585 if (!childHadLayout && child->checkForRepaint()) {
586 if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
588 child->repaintOverhangingFloats(true);
592 // Check for an after page/column break.
593 LayoutUnit newHeight = applyAfterBreak(child, logicalHeight(), marginInfo);
594 if (newHeight != height())
595 setLogicalHeight(newHeight);
598 if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled()) {
599 ASSERT(view()->layoutDeltaMatches(oldLayoutDelta));
603 LayoutUnit RenderBlockFlow::adjustBlockChildForPagination(LayoutUnit logicalTopAfterClear, LayoutUnit estimateWithoutPagination, RenderBox* child, bool atBeforeSideOfBlock)
605 RenderBlock* childRenderBlock = child->isRenderBlock() ? toRenderBlock(child) : 0;
607 if (estimateWithoutPagination != logicalTopAfterClear) {
608 // Our guess prior to pagination movement was wrong. Before we attempt to paginate, let's try again at the new
610 setLogicalHeight(logicalTopAfterClear);
611 setLogicalTopForChild(child, logicalTopAfterClear, ApplyLayoutDelta);
613 if (child->shrinkToAvoidFloats()) {
614 // The child's width depends on the line width.
615 // When the child shifts to clear an item, its width can
616 // change (because it has more available line width).
617 // So go ahead and mark the item as dirty.
618 child->setChildNeedsLayout(MarkOnlyThis);
621 SubtreeLayoutScope layoutScope(child);
623 if (childRenderBlock) {
624 if (!child->avoidsFloats() && childRenderBlock->containsFloats())
625 toRenderBlockFlow(childRenderBlock)->markAllDescendantsWithFloatsForLayout();
626 if (!child->needsLayout())
627 child->markForPaginationRelayoutIfNeeded(layoutScope);
630 // Our guess was wrong. Make the child lay itself out again.
631 child->layoutIfNeeded();
634 LayoutUnit oldTop = logicalTopAfterClear;
636 // If the object has a page or column break value of "before", then we should shift to the top of the next page.
637 LayoutUnit result = applyBeforeBreak(child, logicalTopAfterClear);
639 if (pageLogicalHeightForOffset(result)) {
640 LayoutUnit remainingLogicalHeight = pageRemainingLogicalHeightForOffset(result, ExcludePageBoundary);
641 LayoutUnit spaceShortage = child->logicalHeight() - remainingLogicalHeight;
642 if (spaceShortage > 0) {
643 // If the child crosses a column boundary, report a break, in case nothing inside it has already
644 // done so. The column balancer needs to know how much it has to stretch the columns to make more
645 // content fit. If no breaks are reported (but do occur), the balancer will have no clue. FIXME:
646 // This should be improved, though, because here we just pretend that the child is
647 // unsplittable. A splittable child, on the other hand, has break opportunities at every position
648 // where there's no child content, border or padding. In other words, we risk stretching more
650 setPageBreak(result, spaceShortage);
654 // For replaced elements and scrolled elements, we want to shift them to the next page if they don't fit on the current one.
655 LayoutUnit logicalTopBeforeUnsplittableAdjustment = result;
656 LayoutUnit logicalTopAfterUnsplittableAdjustment = adjustForUnsplittableChild(child, result);
658 LayoutUnit paginationStrut = 0;
659 LayoutUnit unsplittableAdjustmentDelta = logicalTopAfterUnsplittableAdjustment - logicalTopBeforeUnsplittableAdjustment;
660 if (unsplittableAdjustmentDelta)
661 paginationStrut = unsplittableAdjustmentDelta;
662 else if (childRenderBlock && childRenderBlock->paginationStrut())
663 paginationStrut = childRenderBlock->paginationStrut();
665 if (paginationStrut) {
666 // We are willing to propagate out to our parent block as long as we were at the top of the block prior
667 // to collapsing our margins, and as long as we didn't clear or move as a result of other pagination.
668 if (atBeforeSideOfBlock && oldTop == result && !isOutOfFlowPositioned() && !isTableCell()) {
669 // FIXME: Should really check if we're exceeding the page height before propagating the strut, but we don't
670 // have all the information to do so (the strut only has the remaining amount to push). Gecko gets this wrong too
671 // and pushes to the next page anyway, so not too concerned about it.
672 setPaginationStrut(result + paginationStrut);
673 if (childRenderBlock)
674 childRenderBlock->setPaginationStrut(0);
676 result += paginationStrut;
680 // Similar to how we apply clearance. Go ahead and boost height() to be the place where we're going to position the child.
681 setLogicalHeight(logicalHeight() + (result - oldTop));
683 // Return the final adjusted logical top.
687 void RenderBlockFlow::rebuildFloatsFromIntruding()
689 if (m_floatingObjects)
690 m_floatingObjects->setHorizontalWritingMode(isHorizontalWritingMode());
692 HashSet<RenderBox*> oldIntrudingFloatSet;
693 if (!childrenInline() && m_floatingObjects) {
694 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
695 FloatingObjectSetIterator end = floatingObjectSet.end();
696 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
697 FloatingObject* floatingObject = *it;
698 if (!floatingObject->isDescendant())
699 oldIntrudingFloatSet.add(floatingObject->renderer());
703 // Inline blocks are covered by the isReplaced() check in the avoidFloats method.
704 if (avoidsFloats() || isRoot() || isRenderView() || isFloatingOrOutOfFlowPositioned() || isTableCell()) {
705 if (m_floatingObjects) {
706 m_floatingObjects->clear();
708 if (!oldIntrudingFloatSet.isEmpty())
709 markAllDescendantsWithFloatsForLayout();
713 RendererToFloatInfoMap floatMap;
715 if (m_floatingObjects) {
716 if (childrenInline())
717 m_floatingObjects->moveAllToFloatInfoMap(floatMap);
719 m_floatingObjects->clear();
722 // We should not process floats if the parent node is not a RenderBlockFlow. Otherwise, we will add
723 // floats in an invalid context. This will cause a crash arising from a bad cast on the parent.
724 // See <rdar://problem/8049753>, where float property is applied on a text node in a SVG.
725 if (!parent() || !parent()->isRenderBlockFlow())
728 // Attempt to locate a previous sibling with overhanging floats. We skip any elements that are
729 // out of flow (like floating/positioned elements), and we also skip over any objects that may have shifted
731 RenderBlockFlow* parentBlockFlow = toRenderBlockFlow(parent());
732 bool parentHasFloats = false;
733 RenderObject* prev = previousSibling();
734 while (prev && (prev->isFloatingOrOutOfFlowPositioned() || !prev->isBox() || !prev->isRenderBlock() || toRenderBlock(prev)->avoidsFloats())) {
735 if (prev->isFloating())
736 parentHasFloats = true;
737 prev = prev->previousSibling();
740 // First add in floats from the parent. Self-collapsing blocks let their parent track any floats that intrude into
741 // them (as opposed to floats they contain themselves) so check for those here too.
742 LayoutUnit logicalTopOffset = logicalTop();
743 if (parentHasFloats || (prev && toRenderBlockFlow(prev)->isSelfCollapsingBlock() && parentBlockFlow->lowestFloatLogicalBottom() > logicalTopOffset))
744 addIntrudingFloats(parentBlockFlow, parentBlockFlow->logicalLeftOffsetForContent(), logicalTopOffset);
746 LayoutUnit logicalLeftOffset = 0;
748 logicalTopOffset -= toRenderBox(prev)->logicalTop();
750 prev = parentBlockFlow;
751 logicalLeftOffset += parentBlockFlow->logicalLeftOffsetForContent();
754 // Add overhanging floats from the previous RenderBlockFlow, but only if it has a float that intrudes into our space.
755 RenderBlockFlow* blockFlow = toRenderBlockFlow(prev);
756 if (blockFlow->m_floatingObjects && blockFlow->lowestFloatLogicalBottom() > logicalTopOffset)
757 addIntrudingFloats(blockFlow, logicalLeftOffset, logicalTopOffset);
759 if (childrenInline()) {
760 LayoutUnit changeLogicalTop = LayoutUnit::max();
761 LayoutUnit changeLogicalBottom = LayoutUnit::min();
762 if (m_floatingObjects) {
763 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
764 FloatingObjectSetIterator end = floatingObjectSet.end();
765 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
766 FloatingObject* floatingObject = *it;
767 FloatingObject* oldFloatingObject = floatMap.get(floatingObject->renderer());
768 LayoutUnit logicalBottom = logicalBottomForFloat(floatingObject);
769 if (oldFloatingObject) {
770 LayoutUnit oldLogicalBottom = logicalBottomForFloat(oldFloatingObject);
771 if (logicalWidthForFloat(floatingObject) != logicalWidthForFloat(oldFloatingObject) || logicalLeftForFloat(floatingObject) != logicalLeftForFloat(oldFloatingObject)) {
772 changeLogicalTop = 0;
773 changeLogicalBottom = max(changeLogicalBottom, max(logicalBottom, oldLogicalBottom));
775 if (logicalBottom != oldLogicalBottom) {
776 changeLogicalTop = min(changeLogicalTop, min(logicalBottom, oldLogicalBottom));
777 changeLogicalBottom = max(changeLogicalBottom, max(logicalBottom, oldLogicalBottom));
779 LayoutUnit logicalTop = logicalTopForFloat(floatingObject);
780 LayoutUnit oldLogicalTop = logicalTopForFloat(oldFloatingObject);
781 if (logicalTop != oldLogicalTop) {
782 changeLogicalTop = min(changeLogicalTop, min(logicalTop, oldLogicalTop));
783 changeLogicalBottom = max(changeLogicalBottom, max(logicalTop, oldLogicalTop));
787 floatMap.remove(floatingObject->renderer());
788 if (oldFloatingObject->originatingLine() && !selfNeedsLayout()) {
789 ASSERT(oldFloatingObject->originatingLine()->renderer() == this);
790 oldFloatingObject->originatingLine()->markDirty();
792 delete oldFloatingObject;
794 changeLogicalTop = 0;
795 changeLogicalBottom = max(changeLogicalBottom, logicalBottom);
800 RendererToFloatInfoMap::iterator end = floatMap.end();
801 for (RendererToFloatInfoMap::iterator it = floatMap.begin(); it != end; ++it) {
802 FloatingObject* floatingObject = (*it).value;
803 if (!floatingObject->isDescendant()) {
804 changeLogicalTop = 0;
805 changeLogicalBottom = max(changeLogicalBottom, logicalBottomForFloat(floatingObject));
808 deleteAllValues(floatMap);
810 markLinesDirtyInBlockRange(changeLogicalTop, changeLogicalBottom);
811 } else if (!oldIntrudingFloatSet.isEmpty()) {
812 // If there are previously intruding floats that no longer intrude, then children with floats
813 // should also get layout because they might need their floating object lists cleared.
814 if (m_floatingObjects->set().size() < oldIntrudingFloatSet.size()) {
815 markAllDescendantsWithFloatsForLayout();
817 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
818 FloatingObjectSetIterator end = floatingObjectSet.end();
819 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end && !oldIntrudingFloatSet.isEmpty(); ++it)
820 oldIntrudingFloatSet.remove((*it)->renderer());
821 if (!oldIntrudingFloatSet.isEmpty())
822 markAllDescendantsWithFloatsForLayout();
827 void RenderBlockFlow::layoutBlockChildren(bool relayoutChildren, LayoutUnit& maxFloatLogicalBottom, SubtreeLayoutScope& layoutScope, LayoutUnit beforeEdge, LayoutUnit afterEdge)
829 dirtyForLayoutFromPercentageHeightDescendants(layoutScope);
831 // The margin struct caches all our current margin collapsing state. The compact struct caches state when we encounter compacts,
832 MarginInfo marginInfo(this, beforeEdge, afterEdge);
834 // Fieldsets need to find their legend and position it inside the border of the object.
835 // The legend then gets skipped during normal layout. The same is true for ruby text.
836 // It doesn't get included in the normal layout process but is instead skipped.
837 RenderObject* childToExclude = layoutSpecialExcludedChild(relayoutChildren, layoutScope);
839 LayoutUnit previousFloatLogicalBottom = 0;
840 maxFloatLogicalBottom = 0;
842 RenderBox* next = firstChildBox();
843 RenderBox* lastNormalFlowChild = 0;
846 RenderBox* child = next;
847 next = child->nextSiblingBox();
849 LayoutRectRecorder recorder(*child);
851 if (childToExclude == child)
852 continue; // Skip this child, since it will be positioned by the specialized subclass (fieldsets and ruby runs).
854 updateBlockChildDirtyBitsBeforeLayout(relayoutChildren, child);
856 if (child->isOutOfFlowPositioned()) {
857 child->containingBlock()->insertPositionedObject(child);
858 adjustPositionedBlock(child, marginInfo);
861 if (child->isFloating()) {
862 insertFloatingObject(child);
863 adjustFloatingBlock(marginInfo);
867 // Lay out the child.
868 layoutBlockChild(child, marginInfo, previousFloatLogicalBottom, maxFloatLogicalBottom);
869 lastNormalFlowChild = child;
871 // If doing a partial layout and the child was the target renderer, early exit here.
872 if (frameView()->partialLayout().checkPartialLayoutComplete(child))
877 // Now do the handling of the bottom of the block, adding in our bottom border/padding and
878 // determining the correct collapsed bottom margin information.
879 handleAfterSideOfBlock(lastNormalFlowChild, beforeEdge, afterEdge, marginInfo);
882 // Our MarginInfo state used when laying out block children.
883 MarginInfo::MarginInfo(RenderBlockFlow* blockFlow, LayoutUnit beforeBorderPadding, LayoutUnit afterBorderPadding)
884 : m_canCollapseMarginAfterWithLastChild(true)
885 , m_atBeforeSideOfBlock(true)
886 , m_atAfterSideOfBlock(false)
887 , m_hasMarginBeforeQuirk(false)
888 , m_hasMarginAfterQuirk(false)
889 , m_determinedMarginBeforeQuirk(false)
890 , m_discardMargin(false)
892 RenderStyle* blockStyle = blockFlow->style();
893 ASSERT(blockFlow->isRenderView() || blockFlow->parent());
894 m_canCollapseWithChildren = !blockFlow->createsBlockFormattingContext() && !blockFlow->isRenderFlowThread() && !blockFlow->isRenderView();
896 m_canCollapseMarginBeforeWithChildren = m_canCollapseWithChildren && !beforeBorderPadding && blockStyle->marginBeforeCollapse() != MSEPARATE;
898 // If any height other than auto is specified in CSS, then we don't collapse our bottom
899 // margins with our children's margins. To do otherwise would be to risk odd visual
900 // effects when the children overflow out of the parent block and yet still collapse
901 // with it. We also don't collapse if we have any bottom border/padding.
902 m_canCollapseMarginAfterWithChildren = m_canCollapseWithChildren && !afterBorderPadding
903 && (blockStyle->logicalHeight().isAuto() && !blockStyle->logicalHeight().value()) && blockStyle->marginAfterCollapse() != MSEPARATE;
905 m_quirkContainer = blockFlow->isTableCell() || blockFlow->isBody();
907 m_discardMargin = m_canCollapseMarginBeforeWithChildren && blockFlow->mustDiscardMarginBefore();
909 m_positiveMargin = (m_canCollapseMarginBeforeWithChildren && !blockFlow->mustDiscardMarginBefore()) ? blockFlow->maxPositiveMarginBefore() : LayoutUnit();
910 m_negativeMargin = (m_canCollapseMarginBeforeWithChildren && !blockFlow->mustDiscardMarginBefore()) ? blockFlow->maxNegativeMarginBefore() : LayoutUnit();
913 RenderBlockFlow::MarginValues RenderBlockFlow::marginValuesForChild(RenderBox* child) const
915 LayoutUnit childBeforePositive = 0;
916 LayoutUnit childBeforeNegative = 0;
917 LayoutUnit childAfterPositive = 0;
918 LayoutUnit childAfterNegative = 0;
920 LayoutUnit beforeMargin = 0;
921 LayoutUnit afterMargin = 0;
923 RenderBlockFlow* childRenderBlockFlow = child->isRenderBlockFlow() ? toRenderBlockFlow(child) : 0;
925 // If the child has the same directionality as we do, then we can just return its
926 // margins in the same direction.
927 if (!child->isWritingModeRoot()) {
928 if (childRenderBlockFlow) {
929 childBeforePositive = childRenderBlockFlow->maxPositiveMarginBefore();
930 childBeforeNegative = childRenderBlockFlow->maxNegativeMarginBefore();
931 childAfterPositive = childRenderBlockFlow->maxPositiveMarginAfter();
932 childAfterNegative = childRenderBlockFlow->maxNegativeMarginAfter();
934 beforeMargin = child->marginBefore();
935 afterMargin = child->marginAfter();
937 } else if (child->isHorizontalWritingMode() == isHorizontalWritingMode()) {
938 // The child has a different directionality. If the child is parallel, then it's just
939 // flipped relative to us. We can use the margins for the opposite edges.
940 if (childRenderBlockFlow) {
941 childBeforePositive = childRenderBlockFlow->maxPositiveMarginAfter();
942 childBeforeNegative = childRenderBlockFlow->maxNegativeMarginAfter();
943 childAfterPositive = childRenderBlockFlow->maxPositiveMarginBefore();
944 childAfterNegative = childRenderBlockFlow->maxNegativeMarginBefore();
946 beforeMargin = child->marginAfter();
947 afterMargin = child->marginBefore();
950 // The child is perpendicular to us, which means its margins don't collapse but are on the
951 // "logical left/right" sides of the child box. We can just return the raw margin in this case.
952 beforeMargin = marginBeforeForChild(child);
953 afterMargin = marginAfterForChild(child);
956 // Resolve uncollapsing margins into their positive/negative buckets.
958 if (beforeMargin > 0)
959 childBeforePositive = beforeMargin;
961 childBeforeNegative = -beforeMargin;
965 childAfterPositive = afterMargin;
967 childAfterNegative = -afterMargin;
970 return RenderBlockFlow::MarginValues(childBeforePositive, childBeforeNegative, childAfterPositive, childAfterNegative);
973 LayoutUnit RenderBlockFlow::collapseMargins(RenderBox* child, MarginInfo& marginInfo, bool childIsSelfCollapsing)
975 bool childDiscardMarginBefore = mustDiscardMarginBeforeForChild(child);
976 bool childDiscardMarginAfter = mustDiscardMarginAfterForChild(child);
978 // The child discards the before margin when the the after margin has discard in the case of a self collapsing block.
979 childDiscardMarginBefore = childDiscardMarginBefore || (childDiscardMarginAfter && childIsSelfCollapsing);
981 // Get the four margin values for the child and cache them.
982 const RenderBlockFlow::MarginValues childMargins = marginValuesForChild(child);
984 // Get our max pos and neg top margins.
985 LayoutUnit posTop = childMargins.positiveMarginBefore();
986 LayoutUnit negTop = childMargins.negativeMarginBefore();
988 // For self-collapsing blocks, collapse our bottom margins into our
989 // top to get new posTop and negTop values.
990 if (childIsSelfCollapsing) {
991 posTop = max(posTop, childMargins.positiveMarginAfter());
992 negTop = max(negTop, childMargins.negativeMarginAfter());
995 // See if the top margin is quirky. We only care if this child has
996 // margins that will collapse with us.
997 bool topQuirk = hasMarginBeforeQuirk(child);
999 if (marginInfo.canCollapseWithMarginBefore()) {
1000 if (!childDiscardMarginBefore && !marginInfo.discardMargin()) {
1001 // This child is collapsing with the top of the
1002 // block. If it has larger margin values, then we need to update
1003 // our own maximal values.
1004 if (!document().inQuirksMode() || !marginInfo.quirkContainer() || !topQuirk)
1005 setMaxMarginBeforeValues(max(posTop, maxPositiveMarginBefore()), max(negTop, maxNegativeMarginBefore()));
1007 // The minute any of the margins involved isn't a quirk, don't
1008 // collapse it away, even if the margin is smaller (www.webreference.com
1009 // has an example of this, a <dt> with 0.8em author-specified inside
1010 // a <dl> inside a <td>.
1011 if (!marginInfo.determinedMarginBeforeQuirk() && !topQuirk && (posTop - negTop)) {
1012 setHasMarginBeforeQuirk(false);
1013 marginInfo.setDeterminedMarginBeforeQuirk(true);
1016 if (!marginInfo.determinedMarginBeforeQuirk() && topQuirk && !marginBefore()) {
1017 // We have no top margin and our top child has a quirky margin.
1018 // We will pick up this quirky margin and pass it through.
1019 // This deals with the <td><div><p> case.
1020 // Don't do this for a block that split two inlines though. You do
1021 // still apply margins in this case.
1022 setHasMarginBeforeQuirk(true);
1025 // The before margin of the container will also discard all the margins it is collapsing with.
1026 setMustDiscardMarginBefore();
1030 // Once we find a child with discardMarginBefore all the margins collapsing with us must also discard.
1031 if (childDiscardMarginBefore) {
1032 marginInfo.setDiscardMargin(true);
1033 marginInfo.clearMargin();
1036 if (marginInfo.quirkContainer() && marginInfo.atBeforeSideOfBlock() && (posTop - negTop))
1037 marginInfo.setHasMarginBeforeQuirk(topQuirk);
1039 LayoutUnit beforeCollapseLogicalTop = logicalHeight();
1040 LayoutUnit logicalTop = beforeCollapseLogicalTop;
1042 LayoutUnit clearanceForSelfCollapsingBlock;
1043 RenderObject* prev = child->previousSibling();
1044 RenderBlockFlow* previousBlockFlow = prev && prev->isRenderBlockFlow() && !prev->isFloatingOrOutOfFlowPositioned() ? toRenderBlockFlow(prev) : 0;
1045 // 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
1046 // 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
1047 // 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.
1048 if (!marginInfo.canCollapseWithMarginBefore() && previousBlockFlow && previousBlockFlow->isSelfCollapsingBlock()) {
1049 clearanceForSelfCollapsingBlock = previousBlockFlow->marginOffsetForSelfCollapsingBlock();
1050 setLogicalHeight(logicalHeight() - clearanceForSelfCollapsingBlock);
1053 if (childIsSelfCollapsing) {
1054 // 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.
1055 // Also, the child's top position equals the logical height of the container.
1056 if (!childDiscardMarginBefore && !marginInfo.discardMargin()) {
1057 // This child has no height. We need to compute our
1058 // position before we collapse the child's margins together,
1059 // so that we can get an accurate position for the zero-height block.
1060 LayoutUnit collapsedBeforePos = max(marginInfo.positiveMargin(), childMargins.positiveMarginBefore());
1061 LayoutUnit collapsedBeforeNeg = max(marginInfo.negativeMargin(), childMargins.negativeMarginBefore());
1062 marginInfo.setMargin(collapsedBeforePos, collapsedBeforeNeg);
1064 // Now collapse the child's margins together, which means examining our
1065 // bottom margin values as well.
1066 marginInfo.setPositiveMarginIfLarger(childMargins.positiveMarginAfter());
1067 marginInfo.setNegativeMarginIfLarger(childMargins.negativeMarginAfter());
1069 if (!marginInfo.canCollapseWithMarginBefore()) {
1070 // We need to make sure that the position of the self-collapsing block
1071 // is correct, since it could have overflowing content
1072 // that needs to be positioned correctly (e.g., a block that
1073 // had a specified height of 0 but that actually had subcontent).
1074 logicalTop = logicalHeight() + collapsedBeforePos - collapsedBeforeNeg;
1078 if (mustSeparateMarginBeforeForChild(child)) {
1079 ASSERT(!marginInfo.discardMargin() || (marginInfo.discardMargin() && !marginInfo.margin()));
1080 // If we are at the before side of the block and we collapse, ignore the computed margin
1081 // and just add the child margin to the container height. This will correctly position
1082 // the child inside the container.
1083 LayoutUnit separateMargin = !marginInfo.canCollapseWithMarginBefore() ? marginInfo.margin() : LayoutUnit(0);
1084 setLogicalHeight(logicalHeight() + separateMargin + marginBeforeForChild(child));
1085 logicalTop = logicalHeight();
1086 } else if (!marginInfo.discardMargin() && (!marginInfo.atBeforeSideOfBlock()
1087 || (!marginInfo.canCollapseMarginBeforeWithChildren()
1088 && (!document().inQuirksMode() || !marginInfo.quirkContainer() || !marginInfo.hasMarginBeforeQuirk())))) {
1089 // We're collapsing with a previous sibling's margins and not
1090 // with the top of the block.
1091 setLogicalHeight(logicalHeight() + max(marginInfo.positiveMargin(), posTop) - max(marginInfo.negativeMargin(), negTop));
1092 logicalTop = logicalHeight();
1095 marginInfo.setDiscardMargin(childDiscardMarginAfter);
1097 if (!marginInfo.discardMargin()) {
1098 marginInfo.setPositiveMargin(childMargins.positiveMarginAfter());
1099 marginInfo.setNegativeMargin(childMargins.negativeMarginAfter());
1101 marginInfo.clearMargin();
1104 if (marginInfo.margin())
1105 marginInfo.setHasMarginAfterQuirk(hasMarginAfterQuirk(child));
1108 // If margins would pull us past the top of the next page, then we need to pull back and pretend like the margins
1109 // collapsed into the page edge.
1110 LayoutState* layoutState = view()->layoutState();
1111 if (layoutState->isPaginated() && layoutState->pageLogicalHeight() && logicalTop > beforeCollapseLogicalTop) {
1112 LayoutUnit oldLogicalTop = logicalTop;
1113 logicalTop = min(logicalTop, nextPageLogicalTop(beforeCollapseLogicalTop));
1114 setLogicalHeight(logicalHeight() + (logicalTop - oldLogicalTop));
1117 if (previousBlockFlow) {
1118 // 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
1119 // any floats from the parent will now overhang.
1120 LayoutUnit oldLogicalHeight = logicalHeight();
1121 setLogicalHeight(logicalTop);
1122 if (previousBlockFlow->containsFloats() && !previousBlockFlow->avoidsFloats() && (previousBlockFlow->logicalTop() + previousBlockFlow->lowestFloatLogicalBottom()) > logicalTop)
1123 addOverhangingFloats(previousBlockFlow, false);
1124 setLogicalHeight(oldLogicalHeight);
1126 // If |child|'s previous sibling is a self-collapsing block that cleared a float and margin collapsing resulted in |child| moving up
1127 // 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
1128 // floats in the parent that overhang |child|'s new logical top.
1129 bool logicalTopIntrudesIntoFloat = clearanceForSelfCollapsingBlock > 0 && logicalTop < beforeCollapseLogicalTop;
1130 if (logicalTopIntrudesIntoFloat && containsFloats() && !child->avoidsFloats() && lowestFloatLogicalBottom() > logicalTop)
1131 child->setNeedsLayout();
1137 void RenderBlockFlow::adjustPositionedBlock(RenderBox* child, const MarginInfo& marginInfo)
1139 bool isHorizontal = isHorizontalWritingMode();
1140 bool hasStaticBlockPosition = child->style()->hasStaticBlockPosition(isHorizontal);
1142 LayoutUnit logicalTop = logicalHeight();
1143 updateStaticInlinePositionForChild(child, logicalTop);
1145 if (!marginInfo.canCollapseWithMarginBefore()) {
1146 // Positioned blocks don't collapse margins, so add the margin provided by
1147 // the container now. The child's own margin is added later when calculating its logical top.
1148 LayoutUnit collapsedBeforePos = marginInfo.positiveMargin();
1149 LayoutUnit collapsedBeforeNeg = marginInfo.negativeMargin();
1150 logicalTop += collapsedBeforePos - collapsedBeforeNeg;
1153 RenderLayer* childLayer = child->layer();
1154 if (childLayer->staticBlockPosition() != logicalTop) {
1155 childLayer->setStaticBlockPosition(logicalTop);
1156 if (hasStaticBlockPosition)
1157 child->setChildNeedsLayout(MarkOnlyThis);
1161 LayoutUnit RenderBlockFlow::computeStartPositionDeltaForChildAvoidingFloats(const RenderBox* child, LayoutUnit childMarginStart)
1163 LayoutUnit startPosition = startOffsetForContent();
1165 // Add in our start margin.
1166 LayoutUnit oldPosition = startPosition + childMarginStart;
1167 LayoutUnit newPosition = oldPosition;
1169 LayoutUnit blockOffset = logicalTopForChild(child);
1170 LayoutUnit startOff = startOffsetForLine(blockOffset, false, logicalHeightForChild(child));
1172 if (style()->textAlign() != WEBKIT_CENTER && !child->style()->marginStartUsing(style()).isAuto()) {
1173 if (childMarginStart < 0)
1174 startOff += childMarginStart;
1175 newPosition = max(newPosition, startOff); // Let the float sit in the child's margin if it can fit.
1176 } else if (startOff != startPosition) {
1177 newPosition = startOff + childMarginStart;
1180 return newPosition - oldPosition;
1183 LayoutUnit RenderBlockFlow::clearFloatsIfNeeded(RenderBox* child, MarginInfo& marginInfo, LayoutUnit oldTopPosMargin, LayoutUnit oldTopNegMargin, LayoutUnit yPos, bool childIsSelfCollapsing)
1185 LayoutUnit heightIncrease = getClearDelta(child, yPos);
1186 if (!heightIncrease)
1189 if (childIsSelfCollapsing) {
1190 bool childDiscardMargin = mustDiscardMarginBeforeForChild(child) || mustDiscardMarginAfterForChild(child);
1192 // For self-collapsing blocks that clear, they can still collapse their
1193 // margins with following siblings. Reset the current margins to represent
1194 // the self-collapsing block's margins only.
1195 // If DISCARD is specified for -webkit-margin-collapse, reset the margin values.
1196 RenderBlockFlow::MarginValues childMargins = marginValuesForChild(child);
1197 if (!childDiscardMargin) {
1198 marginInfo.setPositiveMargin(max(childMargins.positiveMarginBefore(), childMargins.positiveMarginAfter()));
1199 marginInfo.setNegativeMargin(max(childMargins.negativeMarginBefore(), childMargins.negativeMarginAfter()));
1201 marginInfo.clearMargin();
1203 marginInfo.setDiscardMargin(childDiscardMargin);
1206 // "If the top and bottom margins of an element with clearance are adjoining, its margins collapse with
1207 // the adjoining margins of following siblings but that resulting margin does not collapse with the bottom margin of the parent block."
1208 // So the parent's bottom margin cannot collapse through this block or any subsequent self-collapsing blocks. Set a bit to ensure
1209 // this happens; it will get reset if we encounter an in-flow sibling that is not self-collapsing.
1210 marginInfo.setCanCollapseMarginAfterWithLastChild(false);
1212 // 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
1213 // its own at the correct vertical position. If subsequent siblings attempt to collapse with |child|'s margins in |collapseMargins| we will
1214 // 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
1215 // margins can collapse at the correct vertical position.
1216 // 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
1217 // (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],
1218 // i.e., clearance = [height of float] - margin-top".
1219 setLogicalHeight(child->logicalTop() + childMargins.negativeMarginBefore());
1221 // Increase our height by the amount we had to clear.
1222 setLogicalHeight(logicalHeight() + heightIncrease);
1225 if (marginInfo.canCollapseWithMarginBefore()) {
1226 // We can no longer collapse with the top of the block since a clear
1227 // occurred. The empty blocks collapse into the cleared block.
1228 // FIXME: This isn't quite correct. Need clarification for what to do
1229 // if the height the cleared block is offset by is smaller than the
1230 // margins involved.
1231 setMaxMarginBeforeValues(oldTopPosMargin, oldTopNegMargin);
1232 marginInfo.setAtBeforeSideOfBlock(false);
1234 // In case the child discarded the before margin of the block we need to reset the mustDiscardMarginBefore flag to the initial value.
1235 setMustDiscardMarginBefore(style()->marginBeforeCollapse() == MDISCARD);
1238 return yPos + heightIncrease;
1241 void RenderBlockFlow::setCollapsedBottomMargin(const MarginInfo& marginInfo)
1243 if (marginInfo.canCollapseWithMarginAfter() && !marginInfo.canCollapseWithMarginBefore()) {
1244 // 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.
1245 // Don't update the max margin values because we won't need them anyway.
1246 if (marginInfo.discardMargin()) {
1247 setMustDiscardMarginAfter();
1251 // Update our max pos/neg bottom margins, since we collapsed our bottom margins
1252 // with our children.
1253 setMaxMarginAfterValues(max(maxPositiveMarginAfter(), marginInfo.positiveMargin()), max(maxNegativeMarginAfter(), marginInfo.negativeMargin()));
1255 if (!marginInfo.hasMarginAfterQuirk())
1256 setHasMarginAfterQuirk(false);
1258 if (marginInfo.hasMarginAfterQuirk() && !marginAfter()) {
1259 // We have no bottom margin and our last child has a quirky margin.
1260 // We will pick up this quirky margin and pass it through.
1261 // This deals with the <td><div><p> case.
1262 setHasMarginAfterQuirk(true);
1267 void RenderBlockFlow::marginBeforeEstimateForChild(RenderBox* child, LayoutUnit& positiveMarginBefore, LayoutUnit& negativeMarginBefore, bool& discardMarginBefore) const
1269 // Give up if in quirks mode and we're a body/table cell and the top margin of the child box is quirky.
1270 // Give up if the child specified -webkit-margin-collapse: separate that prevents collapsing.
1271 // FIXME: Use writing mode independent accessor for marginBeforeCollapse.
1272 if ((document().inQuirksMode() && hasMarginAfterQuirk(child) && (isTableCell() || isBody())) || child->style()->marginBeforeCollapse() == MSEPARATE)
1275 // The margins are discarded by a child that specified -webkit-margin-collapse: discard.
1276 // FIXME: Use writing mode independent accessor for marginBeforeCollapse.
1277 if (child->style()->marginBeforeCollapse() == MDISCARD) {
1278 positiveMarginBefore = 0;
1279 negativeMarginBefore = 0;
1280 discardMarginBefore = true;
1284 LayoutUnit beforeChildMargin = marginBeforeForChild(child);
1285 positiveMarginBefore = max(positiveMarginBefore, beforeChildMargin);
1286 negativeMarginBefore = max(negativeMarginBefore, -beforeChildMargin);
1288 if (!child->isRenderBlockFlow())
1291 RenderBlockFlow* childBlockFlow = toRenderBlockFlow(child);
1292 if (childBlockFlow->childrenInline() || childBlockFlow->isWritingModeRoot())
1295 MarginInfo childMarginInfo(childBlockFlow, childBlockFlow->borderBefore() + childBlockFlow->paddingBefore(), childBlockFlow->borderAfter() + childBlockFlow->paddingAfter());
1296 if (!childMarginInfo.canCollapseMarginBeforeWithChildren())
1299 RenderBox* grandchildBox = childBlockFlow->firstChildBox();
1300 for ( ; grandchildBox; grandchildBox = grandchildBox->nextSiblingBox()) {
1301 if (!grandchildBox->isFloatingOrOutOfFlowPositioned())
1305 // Give up if there is clearance on the box, since it probably won't collapse into us.
1306 if (!grandchildBox || grandchildBox->style()->clear() != CNONE)
1309 // Make sure to update the block margins now for the grandchild box so that we're looking at current values.
1310 if (grandchildBox->needsLayout()) {
1311 grandchildBox->computeAndSetBlockDirectionMargins(this);
1312 if (grandchildBox->isRenderBlock()) {
1313 RenderBlock* grandchildBlock = toRenderBlock(grandchildBox);
1314 grandchildBlock->setHasMarginBeforeQuirk(grandchildBox->style()->hasMarginBeforeQuirk());
1315 grandchildBlock->setHasMarginAfterQuirk(grandchildBox->style()->hasMarginAfterQuirk());
1319 // Collapse the margin of the grandchild box with our own to produce an estimate.
1320 childBlockFlow->marginBeforeEstimateForChild(grandchildBox, positiveMarginBefore, negativeMarginBefore, discardMarginBefore);
1323 LayoutUnit RenderBlockFlow::estimateLogicalTopPosition(RenderBox* child, const MarginInfo& marginInfo, LayoutUnit& estimateWithoutPagination)
1325 // FIXME: We need to eliminate the estimation of vertical position, because when it's wrong we sometimes trigger a pathological
1326 // relayout if there are intruding floats.
1327 LayoutUnit logicalTopEstimate = logicalHeight();
1328 if (!marginInfo.canCollapseWithMarginBefore()) {
1329 LayoutUnit positiveMarginBefore = 0;
1330 LayoutUnit negativeMarginBefore = 0;
1331 bool discardMarginBefore = false;
1332 if (child->selfNeedsLayout()) {
1333 // Try to do a basic estimation of how the collapse is going to go.
1334 marginBeforeEstimateForChild(child, positiveMarginBefore, negativeMarginBefore, discardMarginBefore);
1336 // Use the cached collapsed margin values from a previous layout. Most of the time they
1338 RenderBlockFlow::MarginValues marginValues = marginValuesForChild(child);
1339 positiveMarginBefore = max(positiveMarginBefore, marginValues.positiveMarginBefore());
1340 negativeMarginBefore = max(negativeMarginBefore, marginValues.negativeMarginBefore());
1341 discardMarginBefore = mustDiscardMarginBeforeForChild(child);
1344 // Collapse the result with our current margins.
1345 if (!discardMarginBefore)
1346 logicalTopEstimate += max(marginInfo.positiveMargin(), positiveMarginBefore) - max(marginInfo.negativeMargin(), negativeMarginBefore);
1349 // Adjust logicalTopEstimate down to the next page if the margins are so large that we don't fit on the current
1351 LayoutState* layoutState = view()->layoutState();
1352 if (layoutState->isPaginated() && layoutState->pageLogicalHeight() && logicalTopEstimate > logicalHeight())
1353 logicalTopEstimate = min(logicalTopEstimate, nextPageLogicalTop(logicalHeight()));
1355 logicalTopEstimate += getClearDelta(child, logicalTopEstimate);
1357 estimateWithoutPagination = logicalTopEstimate;
1359 if (layoutState->isPaginated()) {
1360 // If the object has a page or column break value of "before", then we should shift to the top of the next page.
1361 logicalTopEstimate = applyBeforeBreak(child, logicalTopEstimate);
1363 // For replaced elements and scrolled elements, we want to shift them to the next page if they don't fit on the current one.
1364 logicalTopEstimate = adjustForUnsplittableChild(child, logicalTopEstimate);
1366 if (!child->selfNeedsLayout() && child->isRenderBlock())
1367 logicalTopEstimate += toRenderBlock(child)->paginationStrut();
1370 return logicalTopEstimate;
1373 LayoutUnit RenderBlockFlow::marginOffsetForSelfCollapsingBlock()
1375 ASSERT(isSelfCollapsingBlock());
1376 RenderBlockFlow* parentBlock = toRenderBlockFlow(parent());
1377 if (parentBlock && style()->clear() && parentBlock->getClearDelta(this, logicalHeight()))
1378 return marginValuesForChild(this).positiveMarginBefore();
1379 return LayoutUnit();
1382 void RenderBlockFlow::adjustFloatingBlock(const MarginInfo& marginInfo)
1384 // The float should be positioned taking into account the bottom margin
1385 // of the previous flow. We add that margin into the height, get the
1386 // float positioned properly, and then subtract the margin out of the
1387 // height again. In the case of self-collapsing blocks, we always just
1388 // use the top margins, since the self-collapsing block collapsed its
1389 // own bottom margin into its top margin.
1391 // Note also that the previous flow may collapse its margin into the top of
1392 // our block. If this is the case, then we do not add the margin in to our
1393 // height when computing the position of the float. This condition can be tested
1394 // for by simply calling canCollapseWithMarginBefore. See
1395 // http://www.hixie.ch/tests/adhoc/css/box/block/margin-collapse/046.html for
1396 // an example of this scenario.
1397 LayoutUnit marginOffset = marginInfo.canCollapseWithMarginBefore() ? LayoutUnit() : marginInfo.margin();
1398 setLogicalHeight(logicalHeight() + marginOffset);
1399 positionNewFloats();
1400 setLogicalHeight(logicalHeight() - marginOffset);
1403 void RenderBlockFlow::handleAfterSideOfBlock(RenderBox* lastChild, LayoutUnit beforeSide, LayoutUnit afterSide, MarginInfo& marginInfo)
1405 marginInfo.setAtAfterSideOfBlock(true);
1407 // If our last child was a self-collapsing block with clearance then our logical height is flush with the
1408 // bottom edge of the float that the child clears. The correct vertical position for the margin-collapsing we want
1409 // to perform now is at the child's margin-top - so adjust our height to that position.
1410 if (lastChild && lastChild->isRenderBlockFlow() && lastChild->isSelfCollapsingBlock())
1411 setLogicalHeight(logicalHeight() - toRenderBlockFlow(lastChild)->marginOffsetForSelfCollapsingBlock());
1413 if (marginInfo.canCollapseMarginAfterWithChildren() && !marginInfo.canCollapseMarginAfterWithLastChild())
1414 marginInfo.setCanCollapseMarginAfterWithChildren(false);
1416 // If we can't collapse with children then go ahead and add in the bottom margin.
1417 if (!marginInfo.discardMargin() && (!marginInfo.canCollapseWithMarginAfter() && !marginInfo.canCollapseWithMarginBefore()
1418 && (!document().inQuirksMode() || !marginInfo.quirkContainer() || !marginInfo.hasMarginAfterQuirk())))
1419 setLogicalHeight(logicalHeight() + marginInfo.margin());
1421 // Now add in our bottom border/padding.
1422 setLogicalHeight(logicalHeight() + afterSide);
1424 // Negative margins can cause our height to shrink below our minimal height (border/padding).
1425 // If this happens, ensure that the computed height is increased to the minimal height.
1426 setLogicalHeight(max(logicalHeight(), beforeSide + afterSide));
1428 // Update our bottom collapsed margin info.
1429 setCollapsedBottomMargin(marginInfo);
1432 void RenderBlockFlow::setMustDiscardMarginBefore(bool value)
1434 if (style()->marginBeforeCollapse() == MDISCARD) {
1439 if (!m_rareData && !value)
1443 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
1445 m_rareData->m_discardMarginBefore = value;
1448 void RenderBlockFlow::setMustDiscardMarginAfter(bool value)
1450 if (style()->marginAfterCollapse() == MDISCARD) {
1455 if (!m_rareData && !value)
1459 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
1461 m_rareData->m_discardMarginAfter = value;
1464 bool RenderBlockFlow::mustDiscardMarginBefore() const
1466 return style()->marginBeforeCollapse() == MDISCARD || (m_rareData && m_rareData->m_discardMarginBefore);
1469 bool RenderBlockFlow::mustDiscardMarginAfter() const
1471 return style()->marginAfterCollapse() == MDISCARD || (m_rareData && m_rareData->m_discardMarginAfter);
1474 bool RenderBlockFlow::mustDiscardMarginBeforeForChild(const RenderBox* child) const
1476 ASSERT(!child->selfNeedsLayout());
1477 if (!child->isWritingModeRoot())
1478 return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginBefore() : (child->style()->marginBeforeCollapse() == MDISCARD);
1479 if (child->isHorizontalWritingMode() == isHorizontalWritingMode())
1480 return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginAfter() : (child->style()->marginAfterCollapse() == MDISCARD);
1482 // FIXME: We return false here because the implementation is not geometrically complete. We have values only for before/after, not start/end.
1483 // In case the boxes are perpendicular we assume the property is not specified.
1487 bool RenderBlockFlow::mustDiscardMarginAfterForChild(const RenderBox* child) const
1489 ASSERT(!child->selfNeedsLayout());
1490 if (!child->isWritingModeRoot())
1491 return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginAfter() : (child->style()->marginAfterCollapse() == MDISCARD);
1492 if (child->isHorizontalWritingMode() == isHorizontalWritingMode())
1493 return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginBefore() : (child->style()->marginBeforeCollapse() == MDISCARD);
1495 // FIXME: See |mustDiscardMarginBeforeForChild| above.
1499 void RenderBlockFlow::setMaxMarginBeforeValues(LayoutUnit pos, LayoutUnit neg)
1502 if (pos == RenderBlockFlowRareData::positiveMarginBeforeDefault(this) && neg == RenderBlockFlowRareData::negativeMarginBeforeDefault(this))
1504 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
1506 m_rareData->m_margins.setPositiveMarginBefore(pos);
1507 m_rareData->m_margins.setNegativeMarginBefore(neg);
1510 void RenderBlockFlow::setMaxMarginAfterValues(LayoutUnit pos, LayoutUnit neg)
1513 if (pos == RenderBlockFlowRareData::positiveMarginAfterDefault(this) && neg == RenderBlockFlowRareData::negativeMarginAfterDefault(this))
1515 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
1517 m_rareData->m_margins.setPositiveMarginAfter(pos);
1518 m_rareData->m_margins.setNegativeMarginAfter(neg);
1521 bool RenderBlockFlow::mustSeparateMarginBeforeForChild(const RenderBox* child) const
1523 ASSERT(!child->selfNeedsLayout());
1524 const RenderStyle* childStyle = child->style();
1525 if (!child->isWritingModeRoot())
1526 return childStyle->marginBeforeCollapse() == MSEPARATE;
1527 if (child->isHorizontalWritingMode() == isHorizontalWritingMode())
1528 return childStyle->marginAfterCollapse() == MSEPARATE;
1530 // FIXME: See |mustDiscardMarginBeforeForChild| above.
1534 bool RenderBlockFlow::mustSeparateMarginAfterForChild(const RenderBox* child) const
1536 ASSERT(!child->selfNeedsLayout());
1537 const RenderStyle* childStyle = child->style();
1538 if (!child->isWritingModeRoot())
1539 return childStyle->marginAfterCollapse() == MSEPARATE;
1540 if (child->isHorizontalWritingMode() == isHorizontalWritingMode())
1541 return childStyle->marginBeforeCollapse() == MSEPARATE;
1543 // FIXME: See |mustDiscardMarginBeforeForChild| above.
1547 LayoutUnit RenderBlockFlow::applyBeforeBreak(RenderBox* child, LayoutUnit logicalOffset)
1549 // FIXME: Add page break checking here when we support printing.
1550 RenderFlowThread* flowThread = flowThreadContainingBlock();
1551 bool isInsideMulticolFlowThread = flowThread;
1552 bool checkColumnBreaks = isInsideMulticolFlowThread || view()->layoutState()->isPaginatingColumns();
1553 bool checkPageBreaks = !checkColumnBreaks && view()->layoutState()->m_pageLogicalHeight; // FIXME: Once columns can print we have to check this.
1554 bool checkBeforeAlways = (checkColumnBreaks && child->style()->columnBreakBefore() == PBALWAYS)
1555 || (checkPageBreaks && child->style()->pageBreakBefore() == PBALWAYS);
1556 if (checkBeforeAlways && inNormalFlow(child)) {
1557 if (checkColumnBreaks) {
1558 if (isInsideMulticolFlowThread) {
1559 LayoutUnit offsetBreakAdjustment = 0;
1560 if (flowThread->addForcedRegionBreak(offsetFromLogicalTopOfFirstPage() + logicalOffset, child, true, &offsetBreakAdjustment))
1561 return logicalOffset + offsetBreakAdjustment;
1563 view()->layoutState()->addForcedColumnBreak(child, logicalOffset);
1566 return nextPageLogicalTop(logicalOffset, IncludePageBoundary);
1568 return logicalOffset;
1571 LayoutUnit RenderBlockFlow::applyAfterBreak(RenderBox* child, LayoutUnit logicalOffset, MarginInfo& marginInfo)
1573 // FIXME: Add page break checking here when we support printing.
1574 RenderFlowThread* flowThread = flowThreadContainingBlock();
1575 bool isInsideMulticolFlowThread = flowThread;
1576 bool checkColumnBreaks = isInsideMulticolFlowThread || view()->layoutState()->isPaginatingColumns();
1577 bool checkPageBreaks = !checkColumnBreaks && view()->layoutState()->m_pageLogicalHeight; // FIXME: Once columns can print we have to check this.
1578 bool checkAfterAlways = (checkColumnBreaks && child->style()->columnBreakAfter() == PBALWAYS)
1579 || (checkPageBreaks && child->style()->pageBreakAfter() == PBALWAYS);
1580 if (checkAfterAlways && inNormalFlow(child)) {
1581 LayoutUnit marginOffset = marginInfo.canCollapseWithMarginBefore() ? LayoutUnit() : marginInfo.margin();
1583 // So our margin doesn't participate in the next collapsing steps.
1584 marginInfo.clearMargin();
1586 if (checkColumnBreaks) {
1587 if (isInsideMulticolFlowThread) {
1588 LayoutUnit offsetBreakAdjustment = 0;
1589 if (flowThread->addForcedRegionBreak(offsetFromLogicalTopOfFirstPage() + logicalOffset + marginOffset, child, false, &offsetBreakAdjustment))
1590 return logicalOffset + marginOffset + offsetBreakAdjustment;
1592 view()->layoutState()->addForcedColumnBreak(child, logicalOffset);
1595 return nextPageLogicalTop(logicalOffset, IncludePageBoundary);
1597 return logicalOffset;
1600 void RenderBlockFlow::addOverflowFromFloats()
1602 if (!m_floatingObjects)
1605 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1606 FloatingObjectSetIterator end = floatingObjectSet.end();
1607 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1608 FloatingObject* floatingObject = *it;
1609 if (floatingObject->isDescendant())
1610 addOverflowFromChild(floatingObject->renderer(), IntSize(xPositionForFloatIncludingMargin(floatingObject), yPositionForFloatIncludingMargin(floatingObject)));
1614 void RenderBlockFlow::computeOverflow(LayoutUnit oldClientAfterEdge, bool recomputeFloats)
1616 RenderBlock::computeOverflow(oldClientAfterEdge, recomputeFloats);
1617 if (!hasColumns() && (recomputeFloats || createsBlockFormattingContext() || hasSelfPaintingLayer()))
1618 addOverflowFromFloats();
1621 RootInlineBox* RenderBlockFlow::createAndAppendRootInlineBox()
1623 RootInlineBox* rootBox = createRootInlineBox();
1624 m_lineBoxes.appendLineBox(rootBox);
1626 if (UNLIKELY(AXObjectCache::accessibilityEnabled()) && m_lineBoxes.firstLineBox() == rootBox) {
1627 if (AXObjectCache* cache = document().existingAXObjectCache())
1628 cache->recomputeIsIgnored(this);
1634 void RenderBlockFlow::deleteLineBoxTree()
1636 if (containsFloats())
1637 m_floatingObjects->clearLineBoxTreePointers();
1638 RenderBlock::deleteLineBoxTree();
1641 void RenderBlockFlow::markAllDescendantsWithFloatsForLayout(RenderBox* floatToRemove, bool inLayout)
1643 if (!everHadLayout() && !containsFloats())
1646 MarkingBehavior markParents = inLayout ? MarkOnlyThis : MarkContainingBlockChain;
1647 setChildNeedsLayout(markParents);
1650 removeFloatingObject(floatToRemove);
1652 // Iterate over our children and mark them as needed.
1653 if (!childrenInline()) {
1654 for (RenderObject* child = firstChild(); child; child = child->nextSibling()) {
1655 if ((!floatToRemove && child->isFloatingOrOutOfFlowPositioned()) || !child->isRenderBlock())
1657 if (!child->isRenderBlockFlow()) {
1658 RenderBlock* childBlock = toRenderBlock(child);
1659 if (childBlock->shrinkToAvoidFloats() && childBlock->everHadLayout())
1660 childBlock->setChildNeedsLayout(markParents);
1663 RenderBlockFlow* childBlockFlow = toRenderBlockFlow(child);
1664 if ((floatToRemove ? childBlockFlow->containsFloat(floatToRemove) : childBlockFlow->containsFloats()) || childBlockFlow->shrinkToAvoidFloats())
1665 childBlockFlow->markAllDescendantsWithFloatsForLayout(floatToRemove, inLayout);
1670 void RenderBlockFlow::markSiblingsWithFloatsForLayout(RenderBox* floatToRemove)
1672 if (!m_floatingObjects)
1675 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1676 FloatingObjectSetIterator end = floatingObjectSet.end();
1678 for (RenderObject* next = nextSibling(); next; next = next->nextSibling()) {
1679 if (!next->isRenderBlockFlow() || next->isFloatingOrOutOfFlowPositioned() || toRenderBlock(next)->avoidsFloats())
1682 RenderBlockFlow* nextBlock = toRenderBlockFlow(next);
1683 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1684 RenderBox* floatingBox = (*it)->renderer();
1685 if (floatToRemove && floatingBox != floatToRemove)
1687 if (nextBlock->containsFloat(floatingBox))
1688 nextBlock->markAllDescendantsWithFloatsForLayout(floatingBox);
1693 LayoutUnit RenderBlockFlow::getClearDelta(RenderBox* child, LayoutUnit logicalTop)
1695 // There is no need to compute clearance if we have no floats.
1696 if (!containsFloats())
1699 // At least one float is present. We need to perform the clearance computation.
1700 bool clearSet = child->style()->clear() != CNONE;
1701 LayoutUnit logicalBottom = 0;
1702 switch (child->style()->clear()) {
1706 logicalBottom = lowestFloatLogicalBottom(FloatingObject::FloatLeft);
1709 logicalBottom = lowestFloatLogicalBottom(FloatingObject::FloatRight);
1712 logicalBottom = lowestFloatLogicalBottom();
1716 // 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).
1717 LayoutUnit result = clearSet ? max<LayoutUnit>(0, logicalBottom - logicalTop) : LayoutUnit();
1718 if (!result && child->avoidsFloats()) {
1719 LayoutUnit newLogicalTop = logicalTop;
1721 LayoutUnit availableLogicalWidthAtNewLogicalTopOffset = availableLogicalWidthForLine(newLogicalTop, false, logicalHeightForChild(child));
1722 if (availableLogicalWidthAtNewLogicalTopOffset == availableLogicalWidthForContent())
1723 return newLogicalTop - logicalTop;
1725 LayoutRect borderBox = child->borderBoxRect();
1726 LayoutUnit childLogicalWidthAtOldLogicalTopOffset = isHorizontalWritingMode() ? borderBox.width() : borderBox.height();
1728 // FIXME: None of this is right for perpendicular writing-mode children.
1729 LayoutUnit childOldLogicalWidth = child->logicalWidth();
1730 LayoutUnit childOldMarginLeft = child->marginLeft();
1731 LayoutUnit childOldMarginRight = child->marginRight();
1732 LayoutUnit childOldLogicalTop = child->logicalTop();
1734 child->setLogicalTop(newLogicalTop);
1735 child->updateLogicalWidth();
1736 borderBox = child->borderBoxRect();
1737 LayoutUnit childLogicalWidthAtNewLogicalTopOffset = isHorizontalWritingMode() ? borderBox.width() : borderBox.height();
1739 child->setLogicalTop(childOldLogicalTop);
1740 child->setLogicalWidth(childOldLogicalWidth);
1741 child->setMarginLeft(childOldMarginLeft);
1742 child->setMarginRight(childOldMarginRight);
1744 if (childLogicalWidthAtNewLogicalTopOffset <= availableLogicalWidthAtNewLogicalTopOffset) {
1745 // Even though we may not be moving, if the logical width did shrink because of the presence of new floats, then
1746 // we need to force a relayout as though we shifted. This happens because of the dynamic addition of overhanging floats
1747 // from previous siblings when negative margins exist on a child (see the addOverhangingFloats call at the end of collapseMargins).
1748 if (childLogicalWidthAtOldLogicalTopOffset != childLogicalWidthAtNewLogicalTopOffset)
1749 child->setChildNeedsLayout(MarkOnlyThis);
1750 return newLogicalTop - logicalTop;
1753 newLogicalTop = nextFloatLogicalBottomBelow(newLogicalTop);
1754 ASSERT(newLogicalTop >= logicalTop);
1755 if (newLogicalTop < logicalTop)
1758 ASSERT_NOT_REACHED();
1763 void RenderBlockFlow::createFloatingObjects()
1765 m_floatingObjects = adoptPtr(new FloatingObjects(this, isHorizontalWritingMode()));
1768 void RenderBlockFlow::styleWillChange(StyleDifference diff, const RenderStyle* newStyle)
1770 RenderStyle* oldStyle = style();
1771 s_canPropagateFloatIntoSibling = oldStyle ? !isFloatingOrOutOfFlowPositioned() && !avoidsFloats() : false;
1772 if (oldStyle && parent() && diff == StyleDifferenceLayout && oldStyle->position() != newStyle->position()
1773 && containsFloats() && !isFloating() && !isOutOfFlowPositioned() && newStyle->hasOutOfFlowPosition())
1774 markAllDescendantsWithFloatsForLayout();
1776 RenderBlock::styleWillChange(diff, newStyle);
1779 void RenderBlockFlow::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
1781 RenderBlock::styleDidChange(diff, oldStyle);
1783 // After our style changed, if we lose our ability to propagate floats into next sibling
1784 // blocks, then we need to find the top most parent containing that overhanging float and
1785 // then mark its descendants with floats for layout and clear all floats from its next
1786 // sibling blocks that exist in our floating objects list. See bug 56299 and 62875.
1787 bool canPropagateFloatIntoSibling = !isFloatingOrOutOfFlowPositioned() && !avoidsFloats();
1788 if (diff == StyleDifferenceLayout && s_canPropagateFloatIntoSibling && !canPropagateFloatIntoSibling && hasOverhangingFloats()) {
1789 RenderBlockFlow* parentBlockFlow = this;
1790 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1791 FloatingObjectSetIterator end = floatingObjectSet.end();
1793 for (RenderObject* curr = parent(); curr && !curr->isRenderView(); curr = curr->parent()) {
1794 if (curr->isRenderBlockFlow()) {
1795 RenderBlockFlow* currBlock = toRenderBlockFlow(curr);
1797 if (currBlock->hasOverhangingFloats()) {
1798 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1799 RenderBox* renderer = (*it)->renderer();
1800 if (currBlock->hasOverhangingFloat(renderer)) {
1801 parentBlockFlow = currBlock;
1809 parentBlockFlow->markAllDescendantsWithFloatsForLayout();
1810 parentBlockFlow->markSiblingsWithFloatsForLayout();
1814 void RenderBlockFlow::updateStaticInlinePositionForChild(RenderBox* child, LayoutUnit logicalTop)
1816 if (child->style()->isOriginalDisplayInlineType())
1817 setStaticInlinePositionForChild(child, logicalTop, startAlignedOffsetForLine(logicalTop, false));
1819 setStaticInlinePositionForChild(child, logicalTop, startOffsetForContent());
1822 void RenderBlockFlow::setStaticInlinePositionForChild(RenderBox* child, LayoutUnit blockOffset, LayoutUnit inlinePosition)
1824 child->layer()->setStaticInlinePosition(inlinePosition);
1827 void RenderBlockFlow::moveAllChildrenIncludingFloatsTo(RenderBlock* toBlock, bool fullRemoveInsert)
1829 RenderBlockFlow* toBlockFlow = toRenderBlockFlow(toBlock);
1830 moveAllChildrenTo(toBlockFlow, fullRemoveInsert);
1832 // When a portion of the render tree is being detached, anonymous blocks
1833 // will be combined as their children are deleted. In this process, the
1834 // anonymous block later in the tree is merged into the one preceeding it.
1835 // It can happen that the later block (this) contains floats that the
1836 // previous block (toBlockFlow) did not contain, and thus are not in the
1837 // floating objects list for toBlockFlow. This can result in toBlockFlow containing
1838 // floats that are not in it's floating objects list, but are in the
1839 // floating objects lists of siblings and parents. This can cause problems
1840 // when the float itself is deleted, since the deletion code assumes that
1841 // if a float is not in it's containing block's floating objects list, it
1842 // isn't in any floating objects list. In order to preserve this condition
1843 // (removing it has serious performance implications), we need to copy the
1844 // floating objects from the old block (this) to the new block (toBlockFlow).
1845 // The float's metrics will likely all be wrong, but since toBlockFlow is
1846 // already marked for layout, this will get fixed before anything gets
1848 // See bug https://code.google.com/p/chromium/issues/detail?id=230907
1849 if (m_floatingObjects) {
1850 if (!toBlockFlow->m_floatingObjects)
1851 toBlockFlow->createFloatingObjects();
1853 const FloatingObjectSet& fromFloatingObjectSet = m_floatingObjects->set();
1854 FloatingObjectSetIterator end = fromFloatingObjectSet.end();
1856 for (FloatingObjectSetIterator it = fromFloatingObjectSet.begin(); it != end; ++it) {
1857 FloatingObject* floatingObject = *it;
1859 // Don't insert the object again if it's already in the list
1860 if (toBlockFlow->containsFloat(floatingObject->renderer()))
1863 toBlockFlow->m_floatingObjects->add(floatingObject->unsafeClone());
1869 void RenderBlockFlow::repaintOverhangingFloats(bool paintAllDescendants)
1871 // Repaint any overhanging floats (if we know we're the one to paint them).
1872 // Otherwise, bail out.
1873 if (!hasOverhangingFloats())
1876 // FIXME: Avoid disabling LayoutState. At the very least, don't disable it for floats originating
1877 // in this block. Better yet would be to push extra state for the containers of other floats.
1878 LayoutStateDisabler layoutStateDisabler(view());
1879 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1880 FloatingObjectSetIterator end = floatingObjectSet.end();
1881 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1882 FloatingObject* floatingObject = *it;
1883 // Only repaint the object if it is overhanging, is not in its own layer, and
1884 // is our responsibility to paint (m_shouldPaint is set). When paintAllDescendants is true, the latter
1885 // condition is replaced with being a descendant of us.
1886 if (logicalBottomForFloat(floatingObject) > logicalHeight()
1887 && !floatingObject->renderer()->hasSelfPaintingLayer()
1888 && (floatingObject->shouldPaint() || (paintAllDescendants && floatingObject->renderer()->isDescendantOf(this)))) {
1890 RenderBox* floatingRenderer = floatingObject->renderer();
1891 LayoutRectRecorder recorder(*floatingRenderer);
1892 if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
1893 floatingRenderer->setShouldDoFullRepaintAfterLayout(true);
1895 floatingRenderer->repaint();
1897 floatingRenderer->repaintOverhangingFloats(false);
1902 void RenderBlockFlow::repaintOverflow()
1904 // FIXME: We could tighten up the left and right invalidation points if we let layoutInlineChildren fill them in based off the particular lines
1905 // it had to lay out. We wouldn't need the hasOverflowClip() hack in that case either.
1906 LayoutUnit repaintLogicalLeft = logicalLeftVisualOverflow();
1907 LayoutUnit repaintLogicalRight = logicalRightVisualOverflow();
1908 if (hasOverflowClip()) {
1909 // 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.
1910 // 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.
1911 // layoutInlineChildren should be patched to compute the entire repaint rect.
1912 repaintLogicalLeft = min(repaintLogicalLeft, logicalLeftLayoutOverflow());
1913 repaintLogicalRight = max(repaintLogicalRight, logicalRightLayoutOverflow());
1916 LayoutRect repaintRect;
1917 if (isHorizontalWritingMode())
1918 repaintRect = LayoutRect(repaintLogicalLeft, m_repaintLogicalTop, repaintLogicalRight - repaintLogicalLeft, m_repaintLogicalBottom - m_repaintLogicalTop);
1920 repaintRect = LayoutRect(m_repaintLogicalTop, repaintLogicalLeft, m_repaintLogicalBottom - m_repaintLogicalTop, repaintLogicalRight - repaintLogicalLeft);
1922 // The repaint rect may be split across columns, in which case adjustRectForColumns() will return the union.
1923 adjustRectForColumns(repaintRect);
1925 repaintRect.inflate(maximalOutlineSize(PaintPhaseOutline));
1927 if (hasOverflowClip()) {
1928 // Adjust repaint rect for scroll offset
1929 repaintRect.move(-scrolledContentOffset());
1931 // Don't allow this rect to spill out of our overflow box.
1932 repaintRect.intersect(LayoutRect(LayoutPoint(), size()));
1935 // Make sure the rect is still non-empty after intersecting for overflow above
1936 if (!repaintRect.isEmpty()) {
1937 repaintRectangle(repaintRect); // We need to do a partial repaint of our content.
1938 if (hasReflection())
1939 repaintRectangle(reflectedRect(repaintRect));
1942 m_repaintLogicalTop = 0;
1943 m_repaintLogicalBottom = 0;
1946 void RenderBlockFlow::paintFloats(PaintInfo& paintInfo, const LayoutPoint& paintOffset, bool preservePhase)
1948 if (!m_floatingObjects)
1951 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1952 FloatingObjectSetIterator end = floatingObjectSet.end();
1953 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1954 FloatingObject* floatingObject = *it;
1955 // Only paint the object if our m_shouldPaint flag is set.
1956 if (floatingObject->shouldPaint() && !floatingObject->renderer()->hasSelfPaintingLayer()) {
1957 PaintInfo currentPaintInfo(paintInfo);
1958 currentPaintInfo.phase = preservePhase ? paintInfo.phase : PaintPhaseBlockBackground;
1959 // FIXME: LayoutPoint version of xPositionForFloatIncludingMargin would make this much cleaner.
1960 LayoutPoint childPoint = flipFloatForWritingModeForChild(floatingObject, LayoutPoint(paintOffset.x() + xPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->x(), paintOffset.y() + yPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->y()));
1961 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
1962 if (!preservePhase) {
1963 currentPaintInfo.phase = PaintPhaseChildBlockBackgrounds;
1964 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
1965 currentPaintInfo.phase = PaintPhaseFloat;
1966 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
1967 currentPaintInfo.phase = PaintPhaseForeground;
1968 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
1969 currentPaintInfo.phase = PaintPhaseOutline;
1970 floatingObject->renderer()->paint(currentPaintInfo, childPoint);
1976 void RenderBlockFlow::clipOutFloatingObjects(RenderBlock* rootBlock, const PaintInfo* paintInfo, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock)
1978 if (m_floatingObjects) {
1979 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
1980 FloatingObjectSetIterator end = floatingObjectSet.end();
1981 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
1982 FloatingObject* floatingObject = *it;
1983 LayoutRect floatBox(offsetFromRootBlock.width() + xPositionForFloatIncludingMargin(floatingObject),
1984 offsetFromRootBlock.height() + yPositionForFloatIncludingMargin(floatingObject),
1985 floatingObject->renderer()->width(), floatingObject->renderer()->height());
1986 rootBlock->flipForWritingMode(floatBox);
1987 floatBox.move(rootBlockPhysicalPosition.x(), rootBlockPhysicalPosition.y());
1988 paintInfo->context->clipOut(pixelSnappedIntRect(floatBox));
1993 void RenderBlockFlow::clearFloats(EClear clear)
1995 positionNewFloats();
1997 LayoutUnit newY = 0;
2000 newY = lowestFloatLogicalBottom(FloatingObject::FloatLeft);
2003 newY = lowestFloatLogicalBottom(FloatingObject::FloatRight);
2006 newY = lowestFloatLogicalBottom();
2010 if (height() < newY)
2011 setLogicalHeight(newY);
2014 bool RenderBlockFlow::containsFloat(RenderBox* renderer) const
2016 return m_floatingObjects && m_floatingObjects->set().contains<FloatingObjectHashTranslator>(renderer);
2019 void RenderBlockFlow::removeFloatingObjects()
2021 if (!m_floatingObjects)
2024 m_floatingObjects->clear();
2027 LayoutPoint RenderBlockFlow::flipFloatForWritingModeForChild(const FloatingObject* child, const LayoutPoint& point) const
2029 if (!style()->isFlippedBlocksWritingMode())
2032 // This is similar to RenderBox::flipForWritingModeForChild. We have to subtract out our left/top offsets twice, since
2033 // it's going to get added back in. We hide this complication here so that the calling code looks normal for the unflipped
2035 if (isHorizontalWritingMode())
2036 return LayoutPoint(point.x(), point.y() + height() - child->renderer()->height() - 2 * yPositionForFloatIncludingMargin(child));
2037 return LayoutPoint(point.x() + width() - child->renderer()->width() - 2 * xPositionForFloatIncludingMargin(child), point.y());
2040 LayoutUnit RenderBlockFlow::logicalLeftOffsetForPositioningFloat(LayoutUnit logicalTop, LayoutUnit fixedOffset, bool applyTextIndent, LayoutUnit* heightRemaining) const
2042 LayoutUnit offset = fixedOffset;
2043 if (m_floatingObjects && m_floatingObjects->hasLeftObjects())
2044 offset = m_floatingObjects->logicalLeftOffsetForPositioningFloat(fixedOffset, logicalTop, heightRemaining);
2045 return adjustLogicalLeftOffsetForLine(offset, applyTextIndent);
2048 LayoutUnit RenderBlockFlow::logicalRightOffsetForPositioningFloat(LayoutUnit logicalTop, LayoutUnit fixedOffset, bool applyTextIndent, LayoutUnit* heightRemaining) const
2050 LayoutUnit offset = fixedOffset;
2051 if (m_floatingObjects && m_floatingObjects->hasRightObjects())
2052 offset = m_floatingObjects->logicalRightOffsetForPositioningFloat(fixedOffset, logicalTop, heightRemaining);
2053 return adjustLogicalRightOffsetForLine(offset, applyTextIndent);
2056 LayoutUnit RenderBlockFlow::adjustLogicalLeftOffsetForLine(LayoutUnit offsetFromFloats, bool applyTextIndent) const
2058 LayoutUnit left = offsetFromFloats;
2060 if (applyTextIndent && style()->isLeftToRightDirection())
2061 left += textIndentOffset();
2066 LayoutUnit RenderBlockFlow::adjustLogicalRightOffsetForLine(LayoutUnit offsetFromFloats, bool applyTextIndent) const
2068 LayoutUnit right = offsetFromFloats;
2070 if (applyTextIndent && !style()->isLeftToRightDirection())
2071 right -= textIndentOffset();
2076 LayoutPoint RenderBlockFlow::computeLogicalLocationForFloat(const FloatingObject* floatingObject, LayoutUnit logicalTopOffset) const
2078 RenderBox* childBox = floatingObject->renderer();
2079 LayoutUnit logicalLeftOffset = logicalLeftOffsetForContent(); // Constant part of left offset.
2080 LayoutUnit logicalRightOffset; // Constant part of right offset.
2081 // FIXME Bug 102948: This only works for shape outside directly set on this block.
2082 ShapeInsideInfo* shapeInsideInfo = this->layoutShapeInsideInfo();
2083 // FIXME: Implement behavior for right floats.
2084 if (shapeInsideInfo) {
2085 LayoutSize floatLogicalSize = logicalSizeForFloat(floatingObject);
2086 // floatingObject's logicalSize doesn't contain the actual height at this point, so we need to calculate it
2087 floatLogicalSize.setHeight(logicalHeightForChild(childBox) + marginBeforeForChild(childBox) + marginAfterForChild(childBox));
2089 // FIXME: If the float doesn't fit in the shape we should push it under the content box
2090 logicalTopOffset = shapeInsideInfo->computeFirstFitPositionForFloat(floatLogicalSize);
2091 if (logicalHeight() > logicalTopOffset)
2092 logicalTopOffset = logicalHeight();
2094 SegmentList segments = shapeInsideInfo->computeSegmentsForLine(logicalTopOffset, floatLogicalSize.height());
2095 // FIXME: Add support for shapes with multiple segments.
2096 if (segments.size() == 1) {
2097 // The segment offsets are relative to the content box.
2098 logicalRightOffset = logicalLeftOffset + segments[0].logicalRight;
2099 logicalLeftOffset += segments[0].logicalLeft;
2102 logicalRightOffset = logicalRightOffsetForContent();
2105 LayoutUnit floatLogicalWidth = min(logicalWidthForFloat(floatingObject), logicalRightOffset - logicalLeftOffset); // The width we look for.
2107 LayoutUnit floatLogicalLeft;
2109 bool insideFlowThread = flowThreadContainingBlock();
2111 if (childBox->style()->floating() == LeftFloat) {
2112 LayoutUnit heightRemainingLeft = 1;
2113 LayoutUnit heightRemainingRight = 1;
2114 floatLogicalLeft = logicalLeftOffsetForPositioningFloat(logicalTopOffset, logicalLeftOffset, false, &heightRemainingLeft);
2115 while (logicalRightOffsetForPositioningFloat(logicalTopOffset, logicalRightOffset, false, &heightRemainingRight) - floatLogicalLeft < floatLogicalWidth) {
2116 logicalTopOffset += min(heightRemainingLeft, heightRemainingRight);
2117 floatLogicalLeft = logicalLeftOffsetForPositioningFloat(logicalTopOffset, logicalLeftOffset, false, &heightRemainingLeft);
2118 if (insideFlowThread) {
2119 // Have to re-evaluate all of our offsets, since they may have changed.
2120 logicalRightOffset = logicalRightOffsetForContent(); // Constant part of right offset.
2121 logicalLeftOffset = logicalLeftOffsetForContent(); // Constant part of left offset.
2122 floatLogicalWidth = min(logicalWidthForFloat(floatingObject), logicalRightOffset - logicalLeftOffset);
2125 floatLogicalLeft = max(logicalLeftOffset - borderAndPaddingLogicalLeft(), floatLogicalLeft);
2127 LayoutUnit heightRemainingLeft = 1;
2128 LayoutUnit heightRemainingRight = 1;
2129 floatLogicalLeft = logicalRightOffsetForPositioningFloat(logicalTopOffset, logicalRightOffset, false, &heightRemainingRight);
2130 while (floatLogicalLeft - logicalLeftOffsetForPositioningFloat(logicalTopOffset, logicalLeftOffset, false, &heightRemainingLeft) < floatLogicalWidth) {
2131 logicalTopOffset += min(heightRemainingLeft, heightRemainingRight);
2132 floatLogicalLeft = logicalRightOffsetForPositioningFloat(logicalTopOffset, logicalRightOffset, false, &heightRemainingRight);
2133 if (insideFlowThread) {
2134 // Have to re-evaluate all of our offsets, since they may have changed.
2135 logicalRightOffset = logicalRightOffsetForContent(); // Constant part of right offset.
2136 logicalLeftOffset = logicalLeftOffsetForContent(); // Constant part of left offset.
2137 floatLogicalWidth = min(logicalWidthForFloat(floatingObject), logicalRightOffset - logicalLeftOffset);
2140 // Use the original width of the float here, since the local variable
2141 // |floatLogicalWidth| was capped to the available line width. See
2142 // fast/block/float/clamped-right-float.html.
2143 floatLogicalLeft -= logicalWidthForFloat(floatingObject);
2146 return LayoutPoint(floatLogicalLeft, logicalTopOffset);
2149 FloatingObject* RenderBlockFlow::insertFloatingObject(RenderBox* floatBox)
2151 ASSERT(floatBox->isFloating());
2153 // Create the list of special objects if we don't aleady have one
2154 if (!m_floatingObjects) {
2155 createFloatingObjects();
2157 // Don't insert the object again if it's already in the list
2158 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2159 FloatingObjectSetIterator it = floatingObjectSet.find<FloatingObjectHashTranslator>(floatBox);
2160 if (it != floatingObjectSet.end())
2164 // Create the special object entry & append it to the list
2166 OwnPtr<FloatingObject> newObj = FloatingObject::create(floatBox);
2168 // Our location is irrelevant if we're unsplittable or no pagination is in effect.
2169 // Just go ahead and lay out the float.
2170 bool isChildRenderBlock = floatBox->isRenderBlock();
2171 if (isChildRenderBlock && !floatBox->needsLayout() && view()->layoutState()->pageLogicalHeightChanged())
2172 floatBox->setChildNeedsLayout(MarkOnlyThis);
2174 bool needsBlockDirectionLocationSetBeforeLayout = isChildRenderBlock && view()->layoutState()->needsBlockDirectionLocationSetBeforeLayout();
2175 if (!needsBlockDirectionLocationSetBeforeLayout || isWritingModeRoot()) { // We are unsplittable if we're a block flow root.
2176 floatBox->layoutIfNeeded();
2178 floatBox->updateLogicalWidth();
2179 floatBox->computeAndSetBlockDirectionMargins(this);
2182 setLogicalWidthForFloat(newObj.get(), logicalWidthForChild(floatBox) + marginStartForChild(floatBox) + marginEndForChild(floatBox));
2184 return m_floatingObjects->add(newObj.release());
2187 void RenderBlockFlow::removeFloatingObject(RenderBox* floatBox)
2189 if (m_floatingObjects) {
2190 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2191 FloatingObjectSetIterator it = floatingObjectSet.find<FloatingObjectHashTranslator>(floatBox);
2192 if (it != floatingObjectSet.end()) {
2193 FloatingObject* floatingObject = *it;
2194 if (childrenInline()) {
2195 LayoutUnit logicalTop = logicalTopForFloat(floatingObject);
2196 LayoutUnit logicalBottom = logicalBottomForFloat(floatingObject);
2198 // Fix for https://bugs.webkit.org/show_bug.cgi?id=54995.
2199 if (logicalBottom < 0 || logicalBottom < logicalTop || logicalTop == LayoutUnit::max()) {
2200 logicalBottom = LayoutUnit::max();
2202 // Special-case zero- and less-than-zero-height floats: those don't touch
2203 // the line that they're on, but it still needs to be dirtied. This is
2204 // accomplished by pretending they have a height of 1.
2205 logicalBottom = max(logicalBottom, logicalTop + 1);
2207 if (floatingObject->originatingLine()) {
2208 if (!selfNeedsLayout()) {
2209 ASSERT(floatingObject->originatingLine()->renderer() == this);
2210 floatingObject->originatingLine()->markDirty();
2212 #if !ASSERT_DISABLED
2213 floatingObject->setOriginatingLine(0);
2216 markLinesDirtyInBlockRange(0, logicalBottom);
2218 m_floatingObjects->remove(floatingObject);
2223 void RenderBlockFlow::removeFloatingObjectsBelow(FloatingObject* lastFloat, int logicalOffset)
2225 if (!containsFloats())
2228 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2229 FloatingObject* curr = floatingObjectSet.last();
2230 while (curr != lastFloat && (!curr->isPlaced() || logicalTopForFloat(curr) >= logicalOffset)) {
2231 m_floatingObjects->remove(curr);
2232 if (floatingObjectSet.isEmpty())
2234 curr = floatingObjectSet.last();
2238 bool RenderBlockFlow::positionNewFloats()
2240 if (!m_floatingObjects)
2243 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2244 if (floatingObjectSet.isEmpty())
2247 // If all floats have already been positioned, then we have no work to do.
2248 if (floatingObjectSet.last()->isPlaced())
2251 // Move backwards through our floating object list until we find a float that has
2252 // already been positioned. Then we'll be able to move forward, positioning all of
2253 // the new floats that need it.
2254 FloatingObjectSetIterator it = floatingObjectSet.end();
2255 --it; // Go to last item.
2256 FloatingObjectSetIterator begin = floatingObjectSet.begin();
2257 FloatingObject* lastPlacedFloatingObject = 0;
2258 while (it != begin) {
2260 if ((*it)->isPlaced()) {
2261 lastPlacedFloatingObject = *it;
2267 LayoutUnit logicalTop = logicalHeight();
2269 // The float cannot start above the top position of the last positioned float.
2270 if (lastPlacedFloatingObject)
2271 logicalTop = max(logicalTopForFloat(lastPlacedFloatingObject), logicalTop);
2273 FloatingObjectSetIterator end = floatingObjectSet.end();
2274 // Now walk through the set of unpositioned floats and place them.
2275 for (; it != end; ++it) {
2276 FloatingObject* floatingObject = *it;
2277 // The containing block is responsible for positioning floats, so if we have floats in our
2278 // list that come from somewhere else, do not attempt to position them.
2279 if (floatingObject->renderer()->containingBlock() != this)
2282 RenderBox* childBox = floatingObject->renderer();
2283 LayoutRectRecorder childBoxRecorder(*childBox);
2285 LayoutUnit childLogicalLeftMargin = style()->isLeftToRightDirection() ? marginStartForChild(childBox) : marginEndForChild(childBox);
2286 LayoutRect oldRect = childBox->frameRect();
2288 if (childBox->style()->clear() & CLEFT)
2289 logicalTop = max(lowestFloatLogicalBottom(FloatingObject::FloatLeft), logicalTop);
2290 if (childBox->style()->clear() & CRIGHT)
2291 logicalTop = max(lowestFloatLogicalBottom(FloatingObject::FloatRight), logicalTop);
2293 LayoutPoint floatLogicalLocation = computeLogicalLocationForFloat(floatingObject, logicalTop);
2295 setLogicalLeftForFloat(floatingObject, floatLogicalLocation.x());
2297 setLogicalLeftForChild(childBox, floatLogicalLocation.x() + childLogicalLeftMargin);
2298 setLogicalTopForChild(childBox, floatLogicalLocation.y() + marginBeforeForChild(childBox));
2300 SubtreeLayoutScope layoutScope(childBox);
2301 LayoutState* layoutState = view()->layoutState();
2302 bool isPaginated = layoutState->isPaginated();
2303 if (isPaginated && !childBox->needsLayout())
2304 childBox->markForPaginationRelayoutIfNeeded(layoutScope);
2306 childBox->layoutIfNeeded();
2309 // If we are unsplittable and don't fit, then we need to move down.
2310 // We include our margins as part of the unsplittable area.
2311 LayoutUnit newLogicalTop = adjustForUnsplittableChild(childBox, floatLogicalLocation.y(), true);
2313 // See if we have a pagination strut that is making us move down further.
2314 // Note that an unsplittable child can't also have a pagination strut, so this is
2315 // exclusive with the case above.
2316 RenderBlock* childBlock = childBox->isRenderBlock() ? toRenderBlock(childBox) : 0;
2317 if (childBlock && childBlock->paginationStrut()) {
2318 newLogicalTop += childBlock->paginationStrut();
2319 childBlock->setPaginationStrut(0);
2322 if (newLogicalTop != floatLogicalLocation.y()) {
2323 floatingObject->setPaginationStrut(newLogicalTop - floatLogicalLocation.y());
2325 floatLogicalLocation = computeLogicalLocationForFloat(floatingObject, newLogicalTop);
2326 setLogicalLeftForFloat(floatingObject, floatLogicalLocation.x());
2328 setLogicalLeftForChild(childBox, floatLogicalLocation.x() + childLogicalLeftMargin);
2329 setLogicalTopForChild(childBox, floatLogicalLocation.y() + marginBeforeForChild(childBox));
2332 childBlock->setChildNeedsLayout(MarkOnlyThis);
2333 childBox->layoutIfNeeded();
2337 setLogicalTopForFloat(floatingObject, floatLogicalLocation.y());
2339 setLogicalHeightForFloat(floatingObject, logicalHeightForChild(childBox) + marginBeforeForChild(childBox) + marginAfterForChild(childBox));
2341 m_floatingObjects->addPlacedObject(floatingObject);
2343 if (ShapeOutsideInfo* shapeOutside = childBox->shapeOutsideInfo())
2344 shapeOutside->setShapeSize(logicalWidthForChild(childBox), logicalHeightForChild(childBox));
2346 // If the child moved, we have to repaint it.
2347 if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled()
2348 && childBox->checkForRepaintDuringLayout())
2349 childBox->repaintDuringLayoutIfMoved(oldRect);
2354 bool RenderBlockFlow::hasOverhangingFloat(RenderBox* renderer)
2356 if (!m_floatingObjects || hasColumns() || !parent())
2359 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2360 FloatingObjectSetIterator it = floatingObjectSet.find<FloatingObjectHashTranslator>(renderer);
2361 if (it == floatingObjectSet.end())
2364 return logicalBottomForFloat(*it) > logicalHeight();
2367 void RenderBlockFlow::addIntrudingFloats(RenderBlockFlow* prev, LayoutUnit logicalLeftOffset, LayoutUnit logicalTopOffset)
2369 ASSERT(!avoidsFloats());
2371 // If the parent or previous sibling doesn't have any floats to add, don't bother.
2372 if (!prev->m_floatingObjects)
2375 logicalLeftOffset += marginLogicalLeft();
2377 const FloatingObjectSet& prevSet = prev->m_floatingObjects->set();
2378 FloatingObjectSetIterator prevEnd = prevSet.end();
2379 for (FloatingObjectSetIterator prevIt = prevSet.begin(); prevIt != prevEnd; ++prevIt) {
2380 FloatingObject* floatingObject = *prevIt;
2381 if (logicalBottomForFloat(floatingObject) > logicalTopOffset) {
2382 if (!m_floatingObjects || !m_floatingObjects->set().contains(floatingObject)) {
2383 // We create the floating object list lazily.
2384 if (!m_floatingObjects)
2385 createFloatingObjects();
2387 // Applying the child's margin makes no sense in the case where the child was passed in.
2388 // since this margin was added already through the modification of the |logicalLeftOffset| variable
2389 // above. |logicalLeftOffset| will equal the margin in this case, so it's already been taken
2390 // into account. Only apply this code if prev is the parent, since otherwise the left margin
2391 // will get applied twice.
2392 LayoutSize offset = isHorizontalWritingMode()
2393 ? LayoutSize(logicalLeftOffset - (prev != parent() ? prev->marginLeft() : LayoutUnit()), logicalTopOffset)
2394 : LayoutSize(logicalTopOffset, logicalLeftOffset - (prev != parent() ? prev->marginTop() : LayoutUnit()));
2396 m_floatingObjects->add(floatingObject->copyToNewContainer(offset));
2402 LayoutUnit RenderBlockFlow::addOverhangingFloats(RenderBlockFlow* child, bool makeChildPaintOtherFloats)
2404 // Prevent floats from being added to the canvas by the root element, e.g., <html>.
2405 if (child->hasOverflowClip() || !child->containsFloats() || child->isRoot() || child->hasColumns() || child->isWritingModeRoot())
2408 LayoutUnit childLogicalTop = child->logicalTop();
2409 LayoutUnit childLogicalLeft = child->logicalLeft();
2410 LayoutUnit lowestFloatLogicalBottom = 0;
2412 // Floats that will remain the child's responsibility to paint should factor into its
2414 FloatingObjectSetIterator childEnd = child->m_floatingObjects->set().end();
2415 for (FloatingObjectSetIterator childIt = child->m_floatingObjects->set().begin(); childIt != childEnd; ++childIt) {
2416 FloatingObject* floatingObject = *childIt;
2417 LayoutUnit logicalBottomForFloat = min(this->logicalBottomForFloat(floatingObject), LayoutUnit::max() - childLogicalTop);
2418 LayoutUnit logicalBottom = childLogicalTop + logicalBottomForFloat;
2419 lowestFloatLogicalBottom = max(lowestFloatLogicalBottom, logicalBottom);
2421 if (logicalBottom > logicalHeight()) {
2422 // If the object is not in the list, we add it now.
2423 if (!containsFloat(floatingObject->renderer())) {
2424 LayoutSize offset = isHorizontalWritingMode() ? LayoutSize(-childLogicalLeft, -childLogicalTop) : LayoutSize(-childLogicalTop, -childLogicalLeft);
2425 bool shouldPaint = false;
2427 // The nearest enclosing layer always paints the float (so that zindex and stacking
2428 // behaves properly). We always want to propagate the desire to paint the float as
2429 // far out as we can, to the outermost block that overlaps the float, stopping only
2430 // if we hit a self-painting layer boundary.
2431 if (floatingObject->renderer()->enclosingFloatPaintingLayer() == enclosingFloatPaintingLayer()) {
2432 floatingObject->setShouldPaint(false);
2435 // We create the floating object list lazily.
2436 if (!m_floatingObjects)
2437 createFloatingObjects();
2439 m_floatingObjects->add(floatingObject->copyToNewContainer(offset, shouldPaint, true));
2442 if (makeChildPaintOtherFloats && !floatingObject->shouldPaint() && !floatingObject->renderer()->hasSelfPaintingLayer()
2443 && floatingObject->renderer()->isDescendantOf(child) && floatingObject->renderer()->enclosingFloatPaintingLayer() == child->enclosingFloatPaintingLayer()) {
2444 // The float is not overhanging from this block, so if it is a descendant of the child, the child should
2445 // paint it (the other case is that it is intruding into the child), unless it has its own layer or enclosing
2447 // If makeChildPaintOtherFloats is false, it means that the child must already know about all the floats
2449 floatingObject->setShouldPaint(true);
2452 // 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
2454 if (floatingObject->isDescendant())
2455 child->addOverflowFromChild(floatingObject->renderer(), LayoutSize(xPositionForFloatIncludingMargin(floatingObject), yPositionForFloatIncludingMargin(floatingObject)));
2458 return lowestFloatLogicalBottom;
2461 LayoutUnit RenderBlockFlow::lowestFloatLogicalBottom(FloatingObject::Type floatType) const
2463 if (!m_floatingObjects)
2466 return m_floatingObjects->lowestFloatLogicalBottom(floatType);
2469 LayoutUnit RenderBlockFlow::nextFloatLogicalBottomBelow(LayoutUnit logicalHeight, ShapeOutsideFloatOffsetMode offsetMode) const
2471 if (!m_floatingObjects)
2472 return logicalHeight;
2474 LayoutUnit logicalBottom = LayoutUnit::max();
2475 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2476 FloatingObjectSetIterator end = floatingObjectSet.end();
2477 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
2478 FloatingObject* floatingObject = *it;
2479 LayoutUnit floatLogicalBottom = logicalBottomForFloat(floatingObject);
2480 ShapeOutsideInfo* shapeOutside = floatingObject->renderer()->shapeOutsideInfo();
2481 if (shapeOutside && (offsetMode == ShapeOutsideFloatShapeOffset)) {
2482 LayoutUnit shapeLogicalBottom = logicalTopForFloat(floatingObject) + marginBeforeForChild(floatingObject->renderer()) + shapeOutside->shapeLogicalBottom();
2483 // Use the shapeLogicalBottom unless it extends outside of the margin box, in which case it is clipped.
2484 if (shapeLogicalBottom < floatLogicalBottom)
2485 floatLogicalBottom = shapeLogicalBottom;
2487 if (floatLogicalBottom > logicalHeight)
2488 logicalBottom = min(floatLogicalBottom, logicalBottom);
2491 return logicalBottom == LayoutUnit::max() ? LayoutUnit() : logicalBottom;
2494 bool RenderBlockFlow::hitTestFloats(const HitTestRequest& request, HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset)
2496 if (!m_floatingObjects)
2499 LayoutPoint adjustedLocation = accumulatedOffset;
2500 if (isRenderView()) {
2501 adjustedLocation += toLayoutSize(toRenderView(this)->frameView()->scrollPosition());
2504 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2505 FloatingObjectSetIterator begin = floatingObjectSet.begin();
2506 for (FloatingObjectSetIterator it = floatingObjectSet.end(); it != begin;) {
2508 FloatingObject* floatingObject = *it;
2509 if (floatingObject->shouldPaint() && !floatingObject->renderer()->hasSelfPaintingLayer()) {
2510 LayoutUnit xOffset = xPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->x();
2511 LayoutUnit yOffset = yPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->y();
2512 LayoutPoint childPoint = flipFloatForWritingModeForChild(floatingObject, adjustedLocation + LayoutSize(xOffset, yOffset));
2513 if (floatingObject->renderer()->hitTest(request, result, locationInContainer, childPoint)) {
2514 updateHitTestResult(result, locationInContainer.point() - toLayoutSize(childPoint));
2523 void RenderBlockFlow::adjustForBorderFit(LayoutUnit x, LayoutUnit& left, LayoutUnit& right) const
2525 RenderBlock::adjustForBorderFit(x, left, right);
2526 if (m_floatingObjects && style()->visibility() == VISIBLE) {
2527 const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
2528 FloatingObjectSetIterator end = floatingObjectSet.end();
2529 for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
2530 FloatingObject* floatingObject = *it;
2531 // Only examine the object if our m_shouldPaint flag is set.
2532 if (floatingObject->shouldPaint()) {
2533 LayoutUnit floatLeft = xPositionForFloatIncludingMargin(floatingObject) - floatingObject->renderer()->x();
2534 LayoutUnit floatRight = floatLeft + floatingObject->renderer()->width();
2535 left = min(left, floatLeft);
2536 right = max(right, floatRight);
2542 LayoutUnit RenderBlockFlow::logicalLeftFloatOffsetForLine(LayoutUnit logicalTop, LayoutUnit fixedOffset, LayoutUnit logicalHeight) const
2544 if (m_floatingObjects && m_floatingObjects->hasLeftObjects())
2545 return m_floatingObjects->logicalLeftOffset(fixedOffset, logicalTop, logicalHeight);
2550 LayoutUnit RenderBlockFlow::logicalRightFloatOffsetForLine(LayoutUnit logicalTop, LayoutUnit fixedOffset, LayoutUnit logicalHeight) const
2552 if (m_floatingObjects && m_floatingObjects->hasRightObjects())
2553 return m_floatingObjects->logicalRightOffset(fixedOffset, logicalTop, logicalHeight);
2558 GapRects RenderBlockFlow::inlineSelectionGaps(RenderBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock,
2559 LayoutUnit& lastLogicalTop, LayoutUnit& lastLogicalLeft, LayoutUnit& lastLogicalRight, const PaintInfo* paintInfo)
2563 bool containsStart = selectionState() == SelectionStart || selectionState() == SelectionBoth;
2565 if (!firstLineBox()) {
2566 if (containsStart) {
2567 // Go ahead and update our lastLogicalTop to be the bottom of the block. <hr>s or empty blocks with height can trip this
2569 lastLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + logicalHeight();
2570 lastLogicalLeft = logicalLeftSelectionOffset(rootBlock, logicalHeight());
2571 lastLogicalRight = logicalRightSelectionOffset(rootBlock, logicalHeight());
2576 RootInlineBox* lastSelectedLine = 0;
2577 RootInlineBox* curr;
2578 for (curr = firstRootBox(); curr && !curr->hasSelectedChildren(); curr = curr->nextRootBox()) { }
2580 // Now paint the gaps for the lines.
2581 for (; curr && curr->hasSelectedChildren(); curr = curr->nextRootBox()) {
2582 LayoutUnit selTop = curr->selectionTopAdjustedForPrecedingBlock();
2583 LayoutUnit selHeight = curr->selectionHeightAdjustedForPrecedingBlock();
2585 if (!containsStart && !lastSelectedLine && selectionState() != SelectionStart && selectionState() != SelectionBoth) {
2586 result.uniteCenter(blockSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, lastLogicalTop,
2587 lastLogicalLeft, lastLogicalRight, selTop, paintInfo));
2590 LayoutRect logicalRect(curr->logicalLeft(), selTop, curr->logicalWidth(), selTop + selHeight);
2591 logicalRect.move(isHorizontalWritingMode() ? offsetFromRootBlock : offsetFromRootBlock.transposedSize());
2592 LayoutRect physicalRect = rootBlock->logicalRectToPhysicalRect(rootBlockPhysicalPosition, logicalRect);
2593 if (!paintInfo || (isHorizontalWritingMode() && physicalRect.y() < paintInfo->rect.maxY() && physicalRect.maxY() > paintInfo->rect.y())
2594 || (!isHorizontalWritingMode() && physicalRect.x() < paintInfo->rect.maxX() && physicalRect.maxX() > paintInfo->rect.x()))
2595 result.unite(curr->lineSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, selTop, selHeight, paintInfo));
2597 lastSelectedLine = curr;
2600 if (containsStart && !lastSelectedLine) {
2601 // VisibleSelection must start just after our last line.
2602 lastSelectedLine = lastRootBox();
2605 if (lastSelectedLine && selectionState() != SelectionEnd && selectionState() != SelectionBoth) {
2606 // Go ahead and update our lastY to be the bottom of the last selected line.
2607 lastLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + lastSelectedLine->selectionBottom();
2608 lastLogicalLeft = logicalLeftSelectionOffset(rootBlock, lastSelectedLine->selectionBottom());
2609 lastLogicalRight = logicalRightSelectionOffset(rootBlock, lastSelectedLine->selectionBottom());
2614 LayoutUnit RenderBlockFlow::logicalLeftSelectionOffset(RenderBlock* rootBlock, LayoutUnit position)
2616 LayoutUnit logicalLeft = logicalLeftOffsetForLine(position, false);
2617 if (logicalLeft == logicalLeftOffsetForContent())
2618 return RenderBlock::logicalLeftSelectionOffset(rootBlock, position);
2620 RenderBlock* cb = this;
2621 while (cb != rootBlock) {
2622 logicalLeft += cb->logicalLeft();
2623 cb = cb->containingBlock();
2628 LayoutUnit RenderBlockFlow::logicalRightSelectionOffset(RenderBlock* rootBlock, LayoutUnit position)
2630 LayoutUnit logicalRight = logicalRightOffsetForLine(position, false);
2631 if (logicalRight == logicalRightOffsetForContent())
2632 return RenderBlock::logicalRightSelectionOffset(rootBlock, position);
2634 RenderBlock* cb = this;
2635 while (cb != rootBlock) {
2636 logicalRight += cb->logicalLeft();
2637 cb = cb->containingBlock();
2639 return logicalRight;
2642 /*template <typename CharacterType>
2643 static inline TextRun constructTextRunInternal(RenderObject* context, const Font& font, const CharacterType* characters, int length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2645 return constructTextRunInternal(context, font, characters, length, style, direction, expansion);
2648 template <typename CharacterType>
2649 static inline TextRun constructTextRunInternal(RenderObject* context, const Font& font, const CharacterType* characters, int length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2653 TextDirection textDirection = direction;
2654 bool directionalOverride = style->rtlOrdering() == VisualOrder;
2656 TextRun run(characters, length, 0, 0, expansion, textDirection, directionalOverride);
2657 if (textRunNeedsRenderingContext(font))
2658 run.setRenderingContext(SVGTextRunRenderingContext::create(context));
2663 template <typename CharacterType>
2664 static inline TextRun constructTextRunInternal(RenderObject* context, const Font& font, const CharacterType* characters, int length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion, TextRunFlags flags)
2668 TextDirection textDirection = direction;
2669 bool directionalOverride = style->rtlOrdering() == VisualOrder;
2670 if (flags != DefaultTextRunFlags) {
2671 if (flags & RespectDirection)
2672 textDirection = style->direction();
2673 if (flags & RespectDirectionOverride)
2674 directionalOverride |= isOverride(style->unicodeBidi());
2677 TextRun run(characters, length, 0, 0, expansion, textDirection, directionalOverride);
2678 if (textRunNeedsRenderingContext(font))
2679 run.setRenderingContext(SVGTextRunRenderingContext::create(context));
2684 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const LChar* characters, int length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2686 return constructTextRunInternal(context, font, characters, length, style, direction, expansion);
2689 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const UChar* characters, int length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2691 return constructTextRunInternal(context, font, characters, length, style, direction, expansion);
2694 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const RenderText* text, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2697 return constructTextRunInternal(context, font, text->characters8(), text->textLength(), style, direction, expansion);
2698 return constructTextRunInternal(context, font, text->characters16(), text->textLength(), style, direction, expansion);
2701 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const RenderText* text, unsigned offset, unsigned length, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion)
2703 ASSERT(offset + length <= text->textLength());
2705 return constructTextRunInternal(context, font, text->characters8() + offset, length, style, direction, expansion);
2706 return constructTextRunInternal(context, font, text->characters16() + offset, length, style, direction, expansion);
2709 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const String& string, RenderStyle* style, TextDirection direction, TextRun::ExpansionBehavior expansion, TextRunFlags flags)
2711 unsigned length = string.length();
2713 return constructTextRunInternal(context, font, static_cast<const LChar*>(0), length, style, direction, expansion, flags);
2714 if (string.is8Bit())
2715 return constructTextRunInternal(context, font, string.characters8(), length, style, direction, expansion, flags);
2716 return constructTextRunInternal(context, font, string.characters16(), length, style, direction, expansion, flags);
2719 TextRun RenderBlockFlow::constructTextRun(RenderObject* context, const Font& font, const String& string, RenderStyle* style, TextRun::ExpansionBehavior expansion, TextRunFlags flags)
2721 bool hasStrongDirectionality;
2722 return constructTextRun(context, font, string, style,
2723 determineDirectionality(string, hasStrongDirectionality),
2727 RootInlineBox* RenderBlockFlow::createRootInlineBox()
2729 return new RootInlineBox(this);
2732 RenderBlockFlow::RenderBlockFlowRareData& RenderBlockFlow::ensureRareData()
2737 m_rareData = adoptPtr(new RenderBlockFlowRareData(this));
2741 } // namespace WebCore