| /* |
| * Copyright (C) 2013 Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "core/layout/LayoutBlockFlow.h" |
| |
| #include "core/dom/AXObjectCache.h" |
| #include "core/frame/FrameView.h" |
| #include "core/frame/LocalFrame.h" |
| #include "core/frame/Settings.h" |
| #include "core/html/HTMLDialogElement.h" |
| #include "core/layout/HitTestLocation.h" |
| #include "core/layout/LayoutAnalyzer.h" |
| #include "core/layout/LayoutFlowThread.h" |
| #include "core/layout/LayoutMultiColumnFlowThread.h" |
| #include "core/layout/LayoutMultiColumnSpannerPlaceholder.h" |
| #include "core/layout/LayoutPagedFlowThread.h" |
| #include "core/layout/LayoutText.h" |
| #include "core/layout/LayoutView.h" |
| #include "core/layout/TextAutosizer.h" |
| #include "core/layout/line/LineBreaker.h" |
| #include "core/layout/line/LineWidth.h" |
| #include "core/paint/BlockFlowPainter.h" |
| #include "core/paint/ClipScope.h" |
| #include "core/paint/DeprecatedPaintLayer.h" |
| #include "core/paint/LayoutObjectDrawingRecorder.h" |
| #include "core/paint/PaintInfo.h" |
| #include "platform/RuntimeEnabledFeatures.h" |
| #include "platform/geometry/TransformState.h" |
| #include "platform/text/BidiTextRun.h" |
| |
| namespace blink { |
| |
| bool LayoutBlockFlow::s_canPropagateFloatIntoSibling = false; |
| |
| struct SameSizeAsMarginInfo { |
| uint16_t bitfields; |
| LayoutUnit margins[2]; |
| }; |
| |
| static_assert(sizeof(LayoutBlockFlow::MarginValues) == sizeof(LayoutUnit[4]), "MarginValues should stay small"); |
| |
| class MarginInfo { |
| // Collapsing flags for whether we can collapse our margins with our children's margins. |
| bool m_canCollapseWithChildren : 1; |
| bool m_canCollapseMarginBeforeWithChildren : 1; |
| bool m_canCollapseMarginAfterWithChildren : 1; |
| bool m_canCollapseMarginAfterWithLastChild: 1; |
| |
| // Whether or not we are a quirky container, i.e., do we collapse away top and bottom |
| // margins in our container. Table cells and the body are the common examples. We |
| // also have a custom style property for Safari RSS to deal with TypePad blog articles. |
| bool m_quirkContainer : 1; |
| |
| // This flag tracks whether we are still looking at child margins that can all collapse together at the beginning of a block. |
| // They may or may not collapse with the top margin of the block (|m_canCollapseTopWithChildren| tells us that), but they will |
| // always be collapsing with one another. This variable can remain set to true through multiple iterations |
| // as long as we keep encountering self-collapsing blocks. |
| bool m_atBeforeSideOfBlock : 1; |
| |
| // This flag is set when we know we're examining bottom margins and we know we're at the bottom of the block. |
| bool m_atAfterSideOfBlock : 1; |
| |
| // These variables are used to detect quirky margins that we need to collapse away (in table cells |
| // and in the body element). |
| bool m_hasMarginBeforeQuirk : 1; |
| bool m_hasMarginAfterQuirk : 1; |
| bool m_determinedMarginBeforeQuirk : 1; |
| |
| bool m_discardMargin : 1; |
| bool m_lastChildIsSelfCollapsingBlockWithClearance : 1; |
| |
| // These flags track the previous maximal positive and negative margins. |
| LayoutUnit m_positiveMargin; |
| LayoutUnit m_negativeMargin; |
| |
| public: |
| MarginInfo(LayoutBlockFlow*, LayoutUnit beforeBorderPadding, LayoutUnit afterBorderPadding); |
| |
| void setAtBeforeSideOfBlock(bool b) { m_atBeforeSideOfBlock = b; } |
| void setAtAfterSideOfBlock(bool b) { m_atAfterSideOfBlock = b; } |
| void clearMargin() |
| { |
| m_positiveMargin = 0; |
| m_negativeMargin = 0; |
| } |
| void setHasMarginBeforeQuirk(bool b) { m_hasMarginBeforeQuirk = b; } |
| void setHasMarginAfterQuirk(bool b) { m_hasMarginAfterQuirk = b; } |
| void setDeterminedMarginBeforeQuirk(bool b) { m_determinedMarginBeforeQuirk = b; } |
| void setPositiveMargin(LayoutUnit p) { ASSERT(!m_discardMargin); m_positiveMargin = p; } |
| void setNegativeMargin(LayoutUnit n) { ASSERT(!m_discardMargin); m_negativeMargin = n; } |
| void setPositiveMarginIfLarger(LayoutUnit p) |
| { |
| ASSERT(!m_discardMargin); |
| if (p > m_positiveMargin) |
| m_positiveMargin = p; |
| } |
| void setNegativeMarginIfLarger(LayoutUnit n) |
| { |
| ASSERT(!m_discardMargin); |
| if (n > m_negativeMargin) |
| m_negativeMargin = n; |
| } |
| |
| void setMargin(LayoutUnit p, LayoutUnit n) { ASSERT(!m_discardMargin); m_positiveMargin = p; m_negativeMargin = n; } |
| void setCanCollapseMarginAfterWithChildren(bool collapse) { m_canCollapseMarginAfterWithChildren = collapse; } |
| void setCanCollapseMarginAfterWithLastChild(bool collapse) { m_canCollapseMarginAfterWithLastChild = collapse; } |
| void setDiscardMargin(bool value) { m_discardMargin = value; } |
| |
| bool atBeforeSideOfBlock() const { return m_atBeforeSideOfBlock; } |
| bool canCollapseWithMarginBefore() const { return m_atBeforeSideOfBlock && m_canCollapseMarginBeforeWithChildren; } |
| bool canCollapseWithMarginAfter() const { return m_atAfterSideOfBlock && m_canCollapseMarginAfterWithChildren; } |
| bool canCollapseMarginBeforeWithChildren() const { return m_canCollapseMarginBeforeWithChildren; } |
| bool canCollapseMarginAfterWithChildren() const { return m_canCollapseMarginAfterWithChildren; } |
| bool canCollapseMarginAfterWithLastChild() const { return m_canCollapseMarginAfterWithLastChild; } |
| bool quirkContainer() const { return m_quirkContainer; } |
| bool determinedMarginBeforeQuirk() const { return m_determinedMarginBeforeQuirk; } |
| bool hasMarginBeforeQuirk() const { return m_hasMarginBeforeQuirk; } |
| bool hasMarginAfterQuirk() const { return m_hasMarginAfterQuirk; } |
| LayoutUnit positiveMargin() const { return m_positiveMargin; } |
| LayoutUnit negativeMargin() const { return m_negativeMargin; } |
| bool discardMargin() const { return m_discardMargin; } |
| LayoutUnit margin() const { return m_positiveMargin - m_negativeMargin; } |
| void setLastChildIsSelfCollapsingBlockWithClearance(bool value) { m_lastChildIsSelfCollapsingBlockWithClearance = value; } |
| bool lastChildIsSelfCollapsingBlockWithClearance() const { return m_lastChildIsSelfCollapsingBlockWithClearance; } |
| }; |
| static bool inNormalFlow(LayoutBox* child) |
| { |
| LayoutBlock* curr = child->containingBlock(); |
| LayoutView* layoutView = child->view(); |
| while (curr && curr != layoutView) { |
| if (curr->isLayoutFlowThread()) |
| return true; |
| if (curr->isFloatingOrOutOfFlowPositioned()) |
| return false; |
| curr = curr->containingBlock(); |
| } |
| return true; |
| } |
| |
| LayoutBlockFlow::LayoutBlockFlow(ContainerNode* node) |
| : LayoutBlock(node) |
| { |
| static_assert(sizeof(MarginInfo) == sizeof(SameSizeAsMarginInfo), "MarginInfo should stay small"); |
| setChildrenInline(true); |
| } |
| |
| LayoutBlockFlow::~LayoutBlockFlow() |
| { |
| } |
| |
| LayoutBlockFlow* LayoutBlockFlow::createAnonymous(Document* document) |
| { |
| LayoutBlockFlow* layoutBlockFlow = new LayoutBlockFlow(nullptr); |
| layoutBlockFlow->setDocumentForAnonymous(document); |
| return layoutBlockFlow; |
| } |
| |
| LayoutObject* LayoutBlockFlow::layoutSpecialExcludedChild(bool relayoutChildren, SubtreeLayoutScope& layoutScope) |
| { |
| LayoutMultiColumnFlowThread* flowThread = multiColumnFlowThread(); |
| if (!flowThread) |
| return nullptr; |
| setLogicalTopForChild(*flowThread, borderBefore() + paddingBefore()); |
| flowThread->layoutColumns(relayoutChildren, layoutScope); |
| determineLogicalLeftPositionForChild(*flowThread); |
| return flowThread; |
| } |
| |
| bool LayoutBlockFlow::updateLogicalWidthAndColumnWidth() |
| { |
| bool relayoutChildren = LayoutBlock::updateLogicalWidthAndColumnWidth(); |
| if (LayoutMultiColumnFlowThread* flowThread = multiColumnFlowThread()) { |
| if (flowThread->needsNewWidth()) |
| return true; |
| } |
| return relayoutChildren; |
| } |
| |
| void LayoutBlockFlow::checkForPaginationLogicalHeightChange(LayoutUnit& pageLogicalHeight, bool& pageLogicalHeightChanged, bool& hasSpecifiedPageLogicalHeight) |
| { |
| if (LayoutMultiColumnFlowThread* flowThread = multiColumnFlowThread()) { |
| LogicalExtentComputedValues computedValues; |
| computeLogicalHeight(LayoutUnit(), logicalTop(), computedValues); |
| LayoutUnit columnHeight = computedValues.m_extent - borderAndPaddingLogicalHeight() - scrollbarLogicalHeight(); |
| pageLogicalHeightChanged = columnHeight != flowThread->columnHeightAvailable(); |
| flowThread->setColumnHeightAvailable(std::max<LayoutUnit>(columnHeight, 0)); |
| } else if (isLayoutFlowThread()) { |
| LayoutFlowThread* flowThread = toLayoutFlowThread(this); |
| |
| // FIXME: This is a hack to always make sure we have a page logical height, if said height |
| // is known. The page logical height thing in LayoutState is meaningless for flow |
| // thread-based pagination (page height isn't necessarily uniform throughout the flow |
| // thread), but as long as it is used universally as a means to determine whether page |
| // height is known or not, we need this. Page height is unknown when column balancing is |
| // enabled and flow thread height is still unknown (i.e. during the first layout pass). When |
| // it's unknown, we need to prevent the pagination code from assuming page breaks everywhere |
| // and thereby eating every top margin. It should be trivial to clean up and get rid of this |
| // hack once the old multicol implementation is gone. |
| pageLogicalHeight = flowThread->isPageLogicalHeightKnown() ? LayoutUnit(1) : LayoutUnit(); |
| |
| pageLogicalHeightChanged = flowThread->pageLogicalSizeChanged(); |
| } |
| } |
| |
| void LayoutBlockFlow::setBreakAtLineToAvoidWidow(int lineToBreak) |
| { |
| ASSERT(lineToBreak >= 0); |
| ensureRareData(); |
| ASSERT(!m_rareData->m_didBreakAtLineToAvoidWidow); |
| m_rareData->m_lineBreakToAvoidWidow = lineToBreak; |
| } |
| |
| void LayoutBlockFlow::setDidBreakAtLineToAvoidWidow() |
| { |
| ASSERT(!shouldBreakAtLineToAvoidWidow()); |
| |
| // This function should be called only after a break was applied to avoid widows |
| // so assert |m_rareData| exists. |
| ASSERT(m_rareData); |
| |
| m_rareData->m_didBreakAtLineToAvoidWidow = true; |
| } |
| |
| void LayoutBlockFlow::clearDidBreakAtLineToAvoidWidow() |
| { |
| if (!m_rareData) |
| return; |
| |
| m_rareData->m_didBreakAtLineToAvoidWidow = false; |
| } |
| |
| void LayoutBlockFlow::clearShouldBreakAtLineToAvoidWidow() const |
| { |
| ASSERT(shouldBreakAtLineToAvoidWidow()); |
| if (!m_rareData) |
| return; |
| |
| m_rareData->m_lineBreakToAvoidWidow = -1; |
| } |
| |
| bool LayoutBlockFlow::isSelfCollapsingBlock() const |
| { |
| m_hasOnlySelfCollapsingChildren = LayoutBlock::isSelfCollapsingBlock(); |
| return m_hasOnlySelfCollapsingChildren; |
| } |
| |
| void LayoutBlockFlow::layoutBlock(bool relayoutChildren) |
| { |
| ASSERT(needsLayout()); |
| ASSERT(isInlineBlockOrInlineTable() || !isInline()); |
| |
| // If we are self-collapsing with self-collapsing descendants this will get set to save us burrowing through our |
| // descendants every time in |isSelfCollapsingBlock|. We reset it here so that |isSelfCollapsingBlock| attempts to burrow |
| // at least once and so that it always gives a reliable result reflecting the latest layout. |
| m_hasOnlySelfCollapsingChildren = false; |
| |
| if (!relayoutChildren && simplifiedLayout()) |
| return; |
| |
| LayoutAnalyzer::BlockScope analyzer(*this); |
| SubtreeLayoutScope layoutScope(*this); |
| |
| // Multiple passes might be required for column based layout. |
| // The number of passes could be as high as the number of columns. |
| bool done = false; |
| LayoutUnit pageLogicalHeight = 0; |
| while (!done) |
| done = layoutBlockFlow(relayoutChildren, pageLogicalHeight, layoutScope); |
| |
| LayoutView* layoutView = view(); |
| if (layoutView->layoutState()->pageLogicalHeight()) |
| setPageLogicalOffset(layoutView->layoutState()->pageLogicalOffset(*this, logicalTop())); |
| |
| updateLayerTransformAfterLayout(); |
| |
| // Update our scroll information if we're overflow:auto/scroll/hidden now that we know if |
| // we overflow or not. |
| updateScrollInfoAfterLayout(); |
| |
| if (m_paintInvalidationLogicalTop != m_paintInvalidationLogicalBottom) { |
| bool hasVisibleContent = style()->visibility() == VISIBLE; |
| if (!hasVisibleContent) { |
| DeprecatedPaintLayer* layer = enclosingLayer(); |
| layer->updateDescendantDependentFlags(); |
| hasVisibleContent = layer->hasVisibleContent(); |
| } |
| if (hasVisibleContent) |
| setShouldInvalidateOverflowForPaint(true); |
| } |
| |
| if (isHTMLDialogElement(node()) && isOutOfFlowPositioned()) |
| positionDialog(); |
| |
| clearNeedsLayout(); |
| } |
| |
| inline bool LayoutBlockFlow::layoutBlockFlow(bool relayoutChildren, LayoutUnit &pageLogicalHeight, SubtreeLayoutScope& layoutScope) |
| { |
| LayoutUnit oldLeft = logicalLeft(); |
| bool logicalWidthChanged = updateLogicalWidthAndColumnWidth(); |
| relayoutChildren |= logicalWidthChanged; |
| |
| rebuildFloatsFromIntruding(); |
| |
| bool pageLogicalHeightChanged = false; |
| bool hasSpecifiedPageLogicalHeight = false; |
| checkForPaginationLogicalHeightChange(pageLogicalHeight, pageLogicalHeightChanged, hasSpecifiedPageLogicalHeight); |
| if (pageLogicalHeightChanged) |
| relayoutChildren = true; |
| |
| LayoutState state(*this, locationOffset(), pageLogicalHeight, pageLogicalHeightChanged, logicalWidthChanged); |
| |
| // We use four values, maxTopPos, maxTopNeg, maxBottomPos, and maxBottomNeg, to track |
| // our current maximal positive and negative margins. These values are used when we |
| // are collapsed with adjacent blocks, so for example, if you have block A and B |
| // collapsing together, then you'd take the maximal positive margin from both A and B |
| // and subtract it from the maximal negative margin from both A and B to get the |
| // true collapsed margin. This algorithm is recursive, so when we finish layout() |
| // our block knows its current maximal positive/negative values. |
| // |
| // Start out by setting our margin values to our current margins. Table cells have |
| // no margins, so we don't fill in the values for table cells. |
| if (!isTableCell()) { |
| initMaxMarginValues(); |
| setHasMarginBeforeQuirk(style()->hasMarginBeforeQuirk()); |
| setHasMarginAfterQuirk(style()->hasMarginAfterQuirk()); |
| setPaginationStrut(0); |
| } |
| |
| LayoutUnit beforeEdge = borderBefore() + paddingBefore(); |
| LayoutUnit afterEdge = borderAfter() + paddingAfter() + scrollbarLogicalHeight(); |
| LayoutUnit previousHeight = logicalHeight(); |
| setLogicalHeight(beforeEdge); |
| |
| m_paintInvalidationLogicalTop = 0; |
| m_paintInvalidationLogicalBottom = 0; |
| if (!firstChild() && !isAnonymousBlock()) |
| setChildrenInline(true); |
| |
| TextAutosizer::LayoutScope textAutosizerLayoutScope(this); |
| |
| if (childrenInline()) |
| layoutInlineChildren(relayoutChildren, m_paintInvalidationLogicalTop, m_paintInvalidationLogicalBottom, afterEdge); |
| else |
| layoutBlockChildren(relayoutChildren, layoutScope, beforeEdge, afterEdge); |
| |
| // Expand our intrinsic height to encompass floats. |
| if (lowestFloatLogicalBottom() > (logicalHeight() - afterEdge) && createsNewFormattingContext()) |
| setLogicalHeight(lowestFloatLogicalBottom() + afterEdge); |
| |
| if (LayoutMultiColumnFlowThread* flowThread = multiColumnFlowThread()) { |
| if (flowThread->recalculateColumnHeights()) { |
| setChildNeedsLayout(MarkOnlyThis); |
| return false; |
| } |
| } |
| |
| if (shouldBreakAtLineToAvoidWidow()) { |
| setEverHadLayout(true); |
| return false; |
| } |
| |
| // Calculate our new height. |
| LayoutUnit oldHeight = logicalHeight(); |
| LayoutUnit oldClientAfterEdge = clientLogicalBottom(); |
| |
| updateLogicalHeight(); |
| LayoutUnit newHeight = logicalHeight(); |
| if (!childrenInline()) { |
| LayoutBlockFlow* lowestBlock = nullptr; |
| bool addedOverhangingFloats = false; |
| // One of our children's floats may have become an overhanging float for us. |
| for (LayoutObject* child = lastChild(); child; child = child->previousSibling()) { |
| // TODO(robhogan): We should exclude blocks that create formatting contexts, not just out of flow or floating blocks. |
| if (child->isLayoutBlockFlow() && !child->isFloatingOrOutOfFlowPositioned()) { |
| LayoutBlockFlow* block = toLayoutBlockFlow(child); |
| lowestBlock = block; |
| if (oldHeight <= newHeight || block->lowestFloatLogicalBottom() + block->logicalTop() <= newHeight) |
| break; |
| addOverhangingFloats(block, false); |
| addedOverhangingFloats = true; |
| } |
| } |
| if (!addedOverhangingFloats) |
| addLowestFloatFromChildren(lowestBlock); |
| } |
| |
| bool heightChanged = (previousHeight != newHeight); |
| if (heightChanged) |
| relayoutChildren = true; |
| |
| layoutPositionedObjects(relayoutChildren || isDocumentElement(), oldLeft != logicalLeft() ? ForcedLayoutAfterContainingBlockMoved : DefaultLayout); |
| |
| // Add overflow from children (unless we're multi-column, since in that case all our child overflow is clipped anyway). |
| computeOverflow(oldClientAfterEdge); |
| |
| m_descendantsWithFloatsMarkedForLayout = false; |
| return true; |
| } |
| |
| void LayoutBlockFlow::addLowestFloatFromChildren(LayoutBlockFlow* block) |
| { |
| // TODO(robhogan): Make createsNewFormattingContext an ASSERT. |
| if (!block || !block->containsFloats() || block->createsNewFormattingContext()) |
| return; |
| |
| FloatingObject* floatingObject = block->m_floatingObjects->lowestFloatingObject(); |
| if (!floatingObject || containsFloat(floatingObject->layoutObject())) |
| return; |
| |
| LayoutSize offset(-block->logicalLeft(), -block->logicalTop()); |
| if (!isHorizontalWritingMode()) |
| offset = offset.transposedSize(); |
| |
| if (!m_floatingObjects) |
| createFloatingObjects(); |
| FloatingObject* newFloatingObject = m_floatingObjects->add(floatingObject->copyToNewContainer(offset, false, true)); |
| newFloatingObject->setIsLowestNonOverhangingFloatInChild(true); |
| } |
| |
| void LayoutBlockFlow::determineLogicalLeftPositionForChild(LayoutBox& child) |
| { |
| LayoutUnit startPosition = borderStart() + paddingStart(); |
| LayoutUnit initialStartPosition = startPosition; |
| if (style()->shouldPlaceBlockDirectionScrollbarOnLogicalLeft()) |
| startPosition -= verticalScrollbarWidth(); |
| LayoutUnit totalAvailableLogicalWidth = borderAndPaddingLogicalWidth() + availableLogicalWidth(); |
| |
| LayoutUnit childMarginStart = marginStartForChild(child); |
| LayoutUnit newPosition = startPosition + childMarginStart; |
| |
| LayoutUnit positionToAvoidFloats; |
| if (child.avoidsFloats() && containsFloats() && !flowThreadContainingBlock()) |
| positionToAvoidFloats = startOffsetForLine(logicalTopForChild(child), false, logicalHeightForChild(child)); |
| |
| // If the child has an offset from the content edge to avoid floats then use that, otherwise let any negative |
| // margin pull it back over the content edge or any positive margin push it out. |
| // If the child is being centred then the margin calculated to do that has factored in any offset required to |
| // avoid floats, so use it if necessary. |
| if (style()->textAlign() == WEBKIT_CENTER || child.style()->marginStartUsing(style()).isAuto()) |
| newPosition = std::max(newPosition, positionToAvoidFloats + childMarginStart); |
| else if (positionToAvoidFloats > initialStartPosition) |
| newPosition = std::max(newPosition, positionToAvoidFloats); |
| |
| setLogicalLeftForChild(child, style()->isLeftToRightDirection() ? newPosition : totalAvailableLogicalWidth - newPosition - logicalWidthForChild(child)); |
| } |
| |
| void LayoutBlockFlow::setLogicalLeftForChild(LayoutBox& child, LayoutUnit logicalLeft) |
| { |
| if (isHorizontalWritingMode()) { |
| child.setX(logicalLeft); |
| } else { |
| child.setY(logicalLeft); |
| } |
| } |
| |
| void LayoutBlockFlow::setLogicalTopForChild(LayoutBox& child, LayoutUnit logicalTop) |
| { |
| if (isHorizontalWritingMode()) { |
| child.setY(logicalTop); |
| } else { |
| child.setX(logicalTop); |
| } |
| } |
| |
| void LayoutBlockFlow::layoutBlockChild(LayoutBox& child, MarginInfo& marginInfo, LayoutUnit& previousFloatLogicalBottom) |
| { |
| LayoutUnit oldPosMarginBefore = maxPositiveMarginBefore(); |
| LayoutUnit oldNegMarginBefore = maxNegativeMarginBefore(); |
| |
| // The child is a normal flow object. Compute the margins we will use for collapsing now. |
| child.computeAndSetBlockDirectionMargins(this); |
| |
| // Try to guess our correct logical top position. In most cases this guess will |
| // be correct. Only if we're wrong (when we compute the real logical top position) |
| // will we have to potentially relayout. |
| LayoutUnit estimateWithoutPagination; |
| LayoutUnit logicalTopEstimate = estimateLogicalTopPosition(child, marginInfo, estimateWithoutPagination); |
| |
| // Cache our old rect so that we can dirty the proper paint invalidation rects if the child moves. |
| LayoutRect oldRect = child.frameRect(); |
| LayoutUnit oldLogicalTop = logicalTopForChild(child); |
| |
| // Go ahead and position the child as though it didn't collapse with the top. |
| setLogicalTopForChild(child, logicalTopEstimate); |
| |
| LayoutBlockFlow* childLayoutBlockFlow = child.isLayoutBlockFlow() ? toLayoutBlockFlow(&child) : 0; |
| bool markDescendantsWithFloats = false; |
| if (logicalTopEstimate != oldLogicalTop && childLayoutBlockFlow && !childLayoutBlockFlow->avoidsFloats() && childLayoutBlockFlow->containsFloats()) { |
| markDescendantsWithFloats = true; |
| } else if (UNLIKELY(logicalTopEstimate.mightBeSaturated())) { |
| // logicalTopEstimate, returned by estimateLogicalTopPosition, might be saturated for |
| // very large elements. If it does the comparison with oldLogicalTop might yield a |
| // false negative as adding and removing margins, borders etc from a saturated number |
| // might yield incorrect results. If this is the case always mark for layout. |
| markDescendantsWithFloats = true; |
| } else if (!child.avoidsFloats() || child.shrinkToAvoidFloats()) { |
| // If an element might be affected by the presence of floats, then always mark it for |
| // layout. |
| LayoutUnit fb = std::max(previousFloatLogicalBottom, lowestFloatLogicalBottom()); |
| if (fb > logicalTopEstimate) |
| markDescendantsWithFloats = true; |
| } |
| |
| if (childLayoutBlockFlow) { |
| if (markDescendantsWithFloats) |
| childLayoutBlockFlow->markAllDescendantsWithFloatsForLayout(); |
| if (!child.isWritingModeRoot()) |
| previousFloatLogicalBottom = std::max(previousFloatLogicalBottom, oldLogicalTop + childLayoutBlockFlow->lowestFloatLogicalBottom()); |
| } |
| |
| SubtreeLayoutScope layoutScope(child); |
| if (!child.needsLayout()) |
| child.markForPaginationRelayoutIfNeeded(layoutScope); |
| |
| bool childNeededLayout = child.needsLayout(); |
| if (childNeededLayout) |
| child.layout(); |
| |
| // Cache if we are at the top of the block right now. |
| bool atBeforeSideOfBlock = marginInfo.atBeforeSideOfBlock(); |
| bool childIsSelfCollapsing = child.isSelfCollapsingBlock(); |
| |
| // Now determine the correct ypos based off examination of collapsing margin |
| // values. |
| LayoutUnit logicalTopBeforeClear = collapseMargins(child, marginInfo, childIsSelfCollapsing); |
| |
| // Now check for clear. |
| LayoutUnit logicalTopAfterClear = clearFloatsIfNeeded(child, marginInfo, oldPosMarginBefore, oldNegMarginBefore, logicalTopBeforeClear, childIsSelfCollapsing); |
| |
| bool paginated = view()->layoutState()->isPaginated(); |
| if (paginated) { |
| logicalTopAfterClear = adjustBlockChildForPagination(logicalTopAfterClear, estimateWithoutPagination, child, |
| atBeforeSideOfBlock && logicalTopBeforeClear == logicalTopAfterClear); |
| } |
| |
| setLogicalTopForChild(child, logicalTopAfterClear); |
| |
| // Now we have a final top position. See if it really does end up being different from our estimate. |
| // clearFloatsIfNeeded can also mark the child as needing a layout even though we didn't move. This happens |
| // when collapseMargins dynamically adds overhanging floats because of a child with negative margins. |
| if (logicalTopAfterClear != logicalTopEstimate || child.needsLayout() || (paginated && childLayoutBlockFlow && childLayoutBlockFlow->shouldBreakAtLineToAvoidWidow())) { |
| SubtreeLayoutScope layoutScope(child); |
| if (child.shrinkToAvoidFloats()) { |
| // The child's width depends on the line width. |
| // When the child shifts to clear an item, its width can |
| // change (because it has more available line width). |
| // So go ahead and mark the item as dirty. |
| layoutScope.setChildNeedsLayout(&child); |
| } |
| |
| if (childLayoutBlockFlow && !childLayoutBlockFlow->avoidsFloats() && childLayoutBlockFlow->containsFloats()) |
| childLayoutBlockFlow->markAllDescendantsWithFloatsForLayout(); |
| |
| if (!child.needsLayout()) |
| child.markForPaginationRelayoutIfNeeded(layoutScope); |
| |
| // Our guess was wrong. Make the child lay itself out again. |
| child.layoutIfNeeded(); |
| } |
| |
| // If we previously encountered a self-collapsing sibling of this child that had clearance then |
| // we set this bit to ensure we would not collapse the child's margins, and those of any subsequent |
| // self-collapsing siblings, with our parent. If this child is not self-collapsing then it can |
| // collapse its margins with the parent so reset the bit. |
| if (!marginInfo.canCollapseMarginAfterWithLastChild() && !childIsSelfCollapsing) |
| marginInfo.setCanCollapseMarginAfterWithLastChild(true); |
| |
| // We are no longer at the top of the block if we encounter a non-empty child. |
| // This has to be done after checking for clear, so that margins can be reset if a clear occurred. |
| if (marginInfo.atBeforeSideOfBlock() && !childIsSelfCollapsing) |
| marginInfo.setAtBeforeSideOfBlock(false); |
| |
| // Now place the child in the correct left position |
| determineLogicalLeftPositionForChild(child); |
| |
| LayoutSize childOffset = child.location() - oldRect.location(); |
| |
| // Update our height now that the child has been placed in the correct position. |
| setLogicalHeight(logicalHeight() + logicalHeightForChild(child)); |
| if (mustSeparateMarginAfterForChild(child)) { |
| setLogicalHeight(logicalHeight() + marginAfterForChild(child)); |
| marginInfo.clearMargin(); |
| } |
| // If the child has overhanging floats that intrude into following siblings (or possibly out |
| // of this block), then the parent gets notified of the floats now. |
| if (childLayoutBlockFlow) |
| addOverhangingFloats(childLayoutBlockFlow, !childNeededLayout); |
| |
| // If the child moved, we have to invalidate its paint as well as any floating/positioned |
| // descendants. An exception is if we need a layout. In this case, we know we're going to |
| // invalidate our paint (and the child) anyway. |
| if (!selfNeedsLayout() && (childOffset.width() || childOffset.height())) |
| child.invalidatePaintForOverhangingFloats(true); |
| |
| if (paginated) { |
| // Check for an after page/column break. |
| LayoutUnit newHeight = applyAfterBreak(child, logicalHeight(), marginInfo); |
| if (newHeight != size().height()) |
| setLogicalHeight(newHeight); |
| } |
| |
| if (child.isLayoutMultiColumnSpannerPlaceholder()) { |
| // The actual column-span:all element is positioned by this placeholder child. |
| positionSpannerDescendant(toLayoutMultiColumnSpannerPlaceholder(child)); |
| } |
| } |
| |
| LayoutUnit LayoutBlockFlow::adjustBlockChildForPagination(LayoutUnit logicalTopAfterClear, LayoutUnit estimateWithoutPagination, LayoutBox& child, bool atBeforeSideOfBlock) |
| { |
| LayoutBlockFlow* childBlockFlow = child.isLayoutBlockFlow() ? toLayoutBlockFlow(&child) : 0; |
| |
| if (estimateWithoutPagination != logicalTopAfterClear) { |
| // Our guess prior to pagination movement was wrong. Before we attempt to paginate, let's try again at the new |
| // position. |
| setLogicalHeight(logicalTopAfterClear); |
| setLogicalTopForChild(child, logicalTopAfterClear); |
| |
| if (child.shrinkToAvoidFloats()) { |
| // The child's width depends on the line width. |
| // When the child shifts to clear an item, its width can |
| // change (because it has more available line width). |
| // So go ahead and mark the item as dirty. |
| child.setChildNeedsLayout(MarkOnlyThis); |
| } |
| |
| SubtreeLayoutScope layoutScope(child); |
| |
| if (childBlockFlow) { |
| if (!childBlockFlow->avoidsFloats() && childBlockFlow->containsFloats()) |
| childBlockFlow->markAllDescendantsWithFloatsForLayout(); |
| if (!child.needsLayout()) |
| child.markForPaginationRelayoutIfNeeded(layoutScope); |
| } |
| |
| // Our guess was wrong. Make the child lay itself out again. |
| child.layoutIfNeeded(); |
| } |
| |
| LayoutUnit oldTop = logicalTopAfterClear; |
| |
| // If the object has a page or column break value of "before", then we should shift to the top of the next page. |
| LayoutUnit result = applyBeforeBreak(child, logicalTopAfterClear); |
| |
| // For replaced elements and scrolled elements, we want to shift them to the next page if they don't fit on the current one. |
| LayoutUnit logicalTopBeforeUnsplittableAdjustment = result; |
| LayoutUnit logicalTopAfterUnsplittableAdjustment = adjustForUnsplittableChild(child, result); |
| |
| LayoutUnit paginationStrut = 0; |
| LayoutUnit unsplittableAdjustmentDelta = logicalTopAfterUnsplittableAdjustment - logicalTopBeforeUnsplittableAdjustment; |
| LayoutUnit childLogicalHeight = child.logicalHeight(); |
| if (unsplittableAdjustmentDelta) { |
| setPageBreak(result, childLogicalHeight - unsplittableAdjustmentDelta); |
| paginationStrut = unsplittableAdjustmentDelta; |
| } else if (childBlockFlow && childBlockFlow->paginationStrut()) { |
| paginationStrut = childBlockFlow->paginationStrut(); |
| } |
| |
| if (paginationStrut) { |
| // We are willing to propagate out to our parent block as long as we were at the top of the block prior |
| // to collapsing our margins, and as long as we didn't clear or move as a result of other pagination. |
| if (atBeforeSideOfBlock && oldTop == result && !isOutOfFlowPositioned() && !isTableCell()) { |
| // FIXME: Should really check if we're exceeding the page height before propagating the strut, but we don't |
| // have all the information to do so (the strut only has the remaining amount to push). Gecko gets this wrong too |
| // and pushes to the next page anyway, so not too concerned about it. |
| setPaginationStrut(result + paginationStrut); |
| if (childBlockFlow) |
| childBlockFlow->setPaginationStrut(0); |
| } else { |
| result += paginationStrut; |
| } |
| } |
| |
| if (!unsplittableAdjustmentDelta) { |
| if (LayoutUnit pageLogicalHeight = pageLogicalHeightForOffset(result)) { |
| LayoutUnit remainingLogicalHeight = pageRemainingLogicalHeightForOffset(result, ExcludePageBoundary); |
| LayoutUnit spaceShortage = childLogicalHeight - remainingLogicalHeight; |
| if (spaceShortage > 0) { |
| // If the child crosses a column boundary, report a break, in case nothing inside it |
| // has already done so. The column balancer needs to know how much it has to stretch |
| // the columns to make more content fit. If no breaks are reported (but do occur), |
| // the balancer will have no clue. Only measure the space after the last column |
| // boundary, in case it crosses more than one. |
| LayoutUnit spaceShortageInLastColumn = intMod(spaceShortage, pageLogicalHeight); |
| setPageBreak(result, spaceShortageInLastColumn ? spaceShortageInLastColumn : spaceShortage); |
| } else if (remainingLogicalHeight == pageLogicalHeight && offsetFromLogicalTopOfFirstPage() + child.logicalTop()) { |
| // We're at the very top of a page or column, and it's not the first one. This child |
| // may turn out to be the smallest piece of content that causes a page break, so we |
| // need to report it. |
| setPageBreak(result, childLogicalHeight); |
| } |
| } |
| } |
| |
| // Similar to how we apply clearance. Go ahead and boost height() to be the place where we're going to position the child. |
| setLogicalHeight(logicalHeight() + (result - oldTop)); |
| |
| // Return the final adjusted logical top. |
| return result; |
| } |
| |
| static inline LayoutUnit calculateMinimumPageHeight(const ComputedStyle& style, RootInlineBox* lastLine, LayoutUnit lineTop, LayoutUnit lineBottom) |
| { |
| // We may require a certain minimum number of lines per page in order to satisfy |
| // orphans and widows, and that may affect the minimum page height. |
| unsigned lineCount = std::max<unsigned>(style.hasAutoOrphans() ? 1 : style.orphans(), style.widows()); |
| if (lineCount > 1) { |
| RootInlineBox* line = lastLine; |
| for (unsigned i = 1; i < lineCount && line->prevRootBox(); i++) |
| line = line->prevRootBox(); |
| |
| // FIXME: Paginating using line overflow isn't all fine. See FIXME in |
| // adjustLinePositionForPagination() for more details. |
| LayoutRect overflow = line->logicalVisualOverflowRect(line->lineTop(), line->lineBottom()); |
| lineTop = std::min(line->lineTopWithLeading(), overflow.y()); |
| } |
| return lineBottom - lineTop; |
| } |
| |
| void LayoutBlockFlow::adjustLinePositionForPagination(RootInlineBox& lineBox, LayoutUnit& delta) |
| { |
| // FIXME: For now we paginate using line overflow. This ensures that lines don't overlap at all when we |
| // put a strut between them for pagination purposes. However, this really isn't the desired layout, since |
| // the line on the top of the next page will appear too far down relative to the same kind of line at the top |
| // of the first column. |
| // |
| // The layout we would like to see is one where the lineTopWithLeading is at the top of the column, and any line overflow |
| // simply spills out above the top of the column. This effect would match what happens at the top of the first column. |
| // We can't achieve this layout, however, until we stop columns from clipping to the column bounds (thus allowing |
| // for overflow to occur), and then cache visible overflow for each column rect. |
| // |
| // Furthermore, the paint we have to do when a column has overflow has to be special. We need to exclude |
| // content that paints in a previous column (and content that paints in the following column). |
| // |
| // For now we'll at least honor the lineTopWithLeading when paginating if it is above the logical top overflow. This will |
| // at least make positive leading work in typical cases. |
| // |
| // FIXME: Another problem with simply moving lines is that the available line width may change (because of floats). |
| // Technically if the location we move the line to has a different line width than our old position, then we need to dirty the |
| // line and all following lines. |
| LayoutRect logicalVisualOverflow = lineBox.logicalVisualOverflowRect(lineBox.lineTop(), lineBox.lineBottom()); |
| LayoutUnit logicalOffset = std::min(lineBox.lineTopWithLeading(), logicalVisualOverflow.y()); |
| LayoutUnit logicalBottom = std::max(lineBox.lineBottomWithLeading(), logicalVisualOverflow.maxY()); |
| LayoutUnit lineHeight = logicalBottom - logicalOffset; |
| updateMinimumPageHeight(logicalOffset, calculateMinimumPageHeight(styleRef(), &lineBox, logicalOffset, logicalBottom)); |
| logicalOffset += delta; |
| lineBox.setPaginationStrut(0); |
| lineBox.setIsFirstAfterPageBreak(false); |
| LayoutUnit pageLogicalHeight = pageLogicalHeightForOffset(logicalOffset); |
| if (!pageLogicalHeight) |
| return; |
| LayoutUnit remainingLogicalHeight = pageRemainingLogicalHeightForOffset(logicalOffset, ExcludePageBoundary); |
| |
| int lineIndex = lineCount(&lineBox); |
| if (remainingLogicalHeight < lineHeight || (shouldBreakAtLineToAvoidWidow() && lineBreakToAvoidWidow() == lineIndex)) { |
| if (shouldBreakAtLineToAvoidWidow() && lineBreakToAvoidWidow() == lineIndex) { |
| clearShouldBreakAtLineToAvoidWidow(); |
| setDidBreakAtLineToAvoidWidow(); |
| } |
| if (lineHeight > pageLogicalHeight) { |
| // Split the top margin in order to avoid splitting the visible part of the line. |
| remainingLogicalHeight -= std::min(lineHeight - pageLogicalHeight, std::max<LayoutUnit>(0, logicalVisualOverflow.y() - lineBox.lineTopWithLeading())); |
| } |
| LayoutUnit totalLogicalHeight = lineHeight + std::max<LayoutUnit>(0, logicalOffset); |
| LayoutUnit pageLogicalHeightAtNewOffset = pageLogicalHeightForOffset(logicalOffset + remainingLogicalHeight); |
| setPageBreak(logicalOffset, lineHeight - remainingLogicalHeight); |
| if (((lineBox == firstRootBox() && totalLogicalHeight < pageLogicalHeightAtNewOffset) || (!style()->hasAutoOrphans() && style()->orphans() >= lineIndex)) |
| && !isOutOfFlowPositioned() && !isTableCell()) { |
| setPaginationStrut(remainingLogicalHeight + std::max<LayoutUnit>(0, logicalOffset)); |
| } else { |
| delta += remainingLogicalHeight; |
| lineBox.setPaginationStrut(remainingLogicalHeight); |
| lineBox.setIsFirstAfterPageBreak(true); |
| } |
| } else if (remainingLogicalHeight == pageLogicalHeight) { |
| // We're at the very top of a page or column. |
| if (lineBox != firstRootBox()) |
| lineBox.setIsFirstAfterPageBreak(true); |
| if (lineBox != firstRootBox() || offsetFromLogicalTopOfFirstPage()) |
| setPageBreak(logicalOffset, lineHeight); |
| } |
| } |
| |
| LayoutUnit LayoutBlockFlow::adjustForUnsplittableChild(LayoutBox& child, LayoutUnit logicalOffset, bool includeMargins) |
| { |
| bool checkColumnBreaks = flowThreadContainingBlock(); |
| bool checkPageBreaks = !checkColumnBreaks && view()->layoutState()->pageLogicalHeight(); |
| bool isUnsplittable = child.isUnsplittableForPagination() || (checkColumnBreaks && child.style()->columnBreakInside() == PBAVOID) |
| || (checkPageBreaks && child.style()->pageBreakInside() == PBAVOID); |
| if (!isUnsplittable) |
| return logicalOffset; |
| LayoutUnit childLogicalHeight = logicalHeightForChild(child) + (includeMargins ? marginBeforeForChild(child) + marginAfterForChild(child) : LayoutUnit()); |
| LayoutUnit pageLogicalHeight = pageLogicalHeightForOffset(logicalOffset); |
| updateMinimumPageHeight(logicalOffset, childLogicalHeight); |
| if (!pageLogicalHeight) |
| return logicalOffset; |
| LayoutUnit remainingLogicalHeight = pageRemainingLogicalHeightForOffset(logicalOffset, ExcludePageBoundary); |
| if (remainingLogicalHeight < childLogicalHeight) |
| return logicalOffset + remainingLogicalHeight; |
| return logicalOffset; |
| } |
| |
| void LayoutBlockFlow::rebuildFloatsFromIntruding() |
| { |
| if (m_floatingObjects) |
| m_floatingObjects->setHorizontalWritingMode(isHorizontalWritingMode()); |
| |
| HashSet<LayoutBox*> oldIntrudingFloatSet; |
| if (!childrenInline() && m_floatingObjects) { |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) { |
| const FloatingObject& floatingObject = *it->get(); |
| if (!floatingObject.isDescendant()) |
| oldIntrudingFloatSet.add(floatingObject.layoutObject()); |
| } |
| } |
| |
| // Inline blocks are covered by the isReplaced() check in the avoidFloats method. |
| if (avoidsFloats() || isDocumentElement() || isLayoutView() || isFloatingOrOutOfFlowPositioned() || isTableCell()) { |
| if (m_floatingObjects) { |
| m_floatingObjects->clear(); |
| } |
| if (!oldIntrudingFloatSet.isEmpty()) |
| markAllDescendantsWithFloatsForLayout(); |
| return; |
| } |
| |
| LayoutBoxToFloatInfoMap floatMap; |
| |
| if (m_floatingObjects) { |
| if (childrenInline()) |
| m_floatingObjects->moveAllToFloatInfoMap(floatMap); |
| else |
| m_floatingObjects->clear(); |
| } |
| |
| // We should not process floats if the parent node is not a LayoutBlockFlow. Otherwise, we will add |
| // floats in an invalid context. This will cause a crash arising from a bad cast on the parent. |
| // See <rdar://problem/8049753>, where float property is applied on a text node in a SVG. |
| if (!parent() || !parent()->isLayoutBlockFlow()) |
| return; |
| |
| // Attempt to locate a previous sibling with overhanging floats. We skip any elements that |
| // may have shifted to avoid floats, and any objects whose floats cannot interact with objects |
| // outside it (i.e. objects that create a new block formatting context). |
| LayoutBlockFlow* parentBlockFlow = toLayoutBlockFlow(parent()); |
| bool parentHasFloats = false; |
| LayoutObject* prev = previousSibling(); |
| while (prev && (!prev->isBox() || !prev->isLayoutBlock() || toLayoutBlock(prev)->avoidsFloats() || toLayoutBlock(prev)->createsNewFormattingContext())) { |
| if (prev->isFloating()) |
| parentHasFloats = true; |
| prev = prev->previousSibling(); |
| } |
| |
| // First add in floats from the parent. Self-collapsing blocks let their parent track any floats that intrude into |
| // them (as opposed to floats they contain themselves) so check for those here too. |
| LayoutUnit logicalTopOffset = logicalTop(); |
| bool parentHasIntrudingFloats = !parentHasFloats && (!prev || toLayoutBlockFlow(prev)->isSelfCollapsingBlock()) && parentBlockFlow->lowestFloatLogicalBottom() > logicalTopOffset; |
| if (parentHasFloats || parentHasIntrudingFloats) |
| addIntrudingFloats(parentBlockFlow, parentBlockFlow->logicalLeftOffsetForContent(), logicalTopOffset); |
| |
| // Add overhanging floats from the previous LayoutBlockFlow, but only if it has a float that intrudes into our space. |
| if (prev) { |
| LayoutBlockFlow* blockFlow = toLayoutBlockFlow(prev); |
| logicalTopOffset -= blockFlow->logicalTop(); |
| if (blockFlow->lowestFloatLogicalBottom() > logicalTopOffset) |
| addIntrudingFloats(blockFlow, 0, logicalTopOffset); |
| } |
| |
| if (childrenInline()) { |
| LayoutUnit changeLogicalTop = LayoutUnit::max(); |
| LayoutUnit changeLogicalBottom = LayoutUnit::min(); |
| if (m_floatingObjects) { |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) { |
| const FloatingObject& floatingObject = *it->get(); |
| FloatingObject* oldFloatingObject = floatMap.get(floatingObject.layoutObject()); |
| LayoutUnit logicalBottom = logicalBottomForFloat(floatingObject); |
| if (oldFloatingObject) { |
| LayoutUnit oldLogicalBottom = logicalBottomForFloat(*oldFloatingObject); |
| if (logicalWidthForFloat(floatingObject) != logicalWidthForFloat(*oldFloatingObject) || logicalLeftForFloat(floatingObject) != logicalLeftForFloat(*oldFloatingObject)) { |
| changeLogicalTop = 0; |
| changeLogicalBottom = std::max(changeLogicalBottom, std::max(logicalBottom, oldLogicalBottom)); |
| } else { |
| if (logicalBottom != oldLogicalBottom) { |
| changeLogicalTop = std::min(changeLogicalTop, std::min(logicalBottom, oldLogicalBottom)); |
| changeLogicalBottom = std::max(changeLogicalBottom, std::max(logicalBottom, oldLogicalBottom)); |
| } |
| LayoutUnit logicalTop = logicalTopForFloat(floatingObject); |
| LayoutUnit oldLogicalTop = logicalTopForFloat(*oldFloatingObject); |
| if (logicalTop != oldLogicalTop) { |
| changeLogicalTop = std::min(changeLogicalTop, std::min(logicalTop, oldLogicalTop)); |
| changeLogicalBottom = std::max(changeLogicalBottom, std::max(logicalTop, oldLogicalTop)); |
| } |
| } |
| |
| if (oldFloatingObject->originatingLine() && !selfNeedsLayout()) { |
| ASSERT(oldFloatingObject->originatingLine()->layoutObject() == this); |
| oldFloatingObject->originatingLine()->markDirty(); |
| } |
| |
| floatMap.remove(floatingObject.layoutObject()); |
| } else { |
| changeLogicalTop = 0; |
| changeLogicalBottom = std::max(changeLogicalBottom, logicalBottom); |
| } |
| } |
| } |
| |
| LayoutBoxToFloatInfoMap::iterator end = floatMap.end(); |
| for (LayoutBoxToFloatInfoMap::iterator it = floatMap.begin(); it != end; ++it) { |
| OwnPtr<FloatingObject>& floatingObject = it->value; |
| if (!floatingObject->isDescendant()) { |
| changeLogicalTop = 0; |
| changeLogicalBottom = std::max(changeLogicalBottom, logicalBottomForFloat(*floatingObject)); |
| } |
| } |
| |
| markLinesDirtyInBlockRange(changeLogicalTop, changeLogicalBottom); |
| } else if (!oldIntrudingFloatSet.isEmpty()) { |
| // If there are previously intruding floats that no longer intrude, then children with floats |
| // should also get layout because they might need their floating object lists cleared. |
| if (m_floatingObjects->set().size() < oldIntrudingFloatSet.size()) { |
| markAllDescendantsWithFloatsForLayout(); |
| } else { |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end && !oldIntrudingFloatSet.isEmpty(); ++it) |
| oldIntrudingFloatSet.remove((*it)->layoutObject()); |
| if (!oldIntrudingFloatSet.isEmpty()) |
| markAllDescendantsWithFloatsForLayout(); |
| } |
| } |
| } |
| |
| void LayoutBlockFlow::layoutBlockChildren(bool relayoutChildren, SubtreeLayoutScope& layoutScope, LayoutUnit beforeEdge, LayoutUnit afterEdge) |
| { |
| dirtyForLayoutFromPercentageHeightDescendants(layoutScope); |
| |
| // The margin struct caches all our current margin collapsing state. The compact struct caches state when we encounter compacts, |
| MarginInfo marginInfo(this, beforeEdge, afterEdge); |
| |
| // Fieldsets need to find their legend and position it inside the border of the object. |
| // The legend then gets skipped during normal layout. The same is true for ruby text. |
| // It doesn't get included in the normal layout process but is instead skipped. |
| LayoutObject* childToExclude = layoutSpecialExcludedChild(relayoutChildren, layoutScope); |
| |
| LayoutUnit previousFloatLogicalBottom = 0; |
| |
| LayoutBox* next = firstChildBox(); |
| LayoutBox* lastNormalFlowChild = nullptr; |
| |
| while (next) { |
| LayoutBox* child = next; |
| next = child->nextSiblingBox(); |
| |
| child->setMayNeedPaintInvalidation(); |
| |
| if (childToExclude == child) |
| continue; // Skip this child, since it will be positioned by the specialized subclass (fieldsets and ruby runs). |
| |
| updateBlockChildDirtyBitsBeforeLayout(relayoutChildren, *child); |
| |
| if (child->isOutOfFlowPositioned()) { |
| child->containingBlock()->insertPositionedObject(child); |
| adjustPositionedBlock(*child, marginInfo); |
| continue; |
| } |
| if (child->isFloating()) { |
| insertFloatingObject(*child); |
| adjustFloatingBlock(marginInfo); |
| continue; |
| } |
| if (child->isColumnSpanAll()) { |
| // This is not the containing block of the spanner. The spanner's placeholder will lay |
| // it out in due course. For now we just need to consult our flow thread, so that the |
| // columns (if any) preceding and following the spanner are laid out correctly. But |
| // first we apply the pending margin, so that it's taken into consideration and doesn't |
| // end up on the other side of the spanner. |
| setLogicalHeight(logicalHeight() + marginInfo.margin()); |
| marginInfo.clearMargin(); |
| |
| flowThreadContainingBlock()->skipColumnSpanner(child, offsetFromLogicalTopOfFirstPage() + logicalHeight()); |
| continue; |
| } |
| |
| // Lay out the child. |
| layoutBlockChild(*child, marginInfo, previousFloatLogicalBottom); |
| lastNormalFlowChild = child; |
| } |
| |
| // Now do the handling of the bottom of the block, adding in our bottom border/padding and |
| // determining the correct collapsed bottom margin information. |
| handleAfterSideOfBlock(lastNormalFlowChild, beforeEdge, afterEdge, marginInfo); |
| } |
| |
| // Our MarginInfo state used when laying out block children. |
| MarginInfo::MarginInfo(LayoutBlockFlow* blockFlow, LayoutUnit beforeBorderPadding, LayoutUnit afterBorderPadding) |
| : m_canCollapseMarginAfterWithLastChild(true) |
| , m_atBeforeSideOfBlock(true) |
| , m_atAfterSideOfBlock(false) |
| , m_hasMarginBeforeQuirk(false) |
| , m_hasMarginAfterQuirk(false) |
| , m_determinedMarginBeforeQuirk(false) |
| , m_discardMargin(false) |
| , m_lastChildIsSelfCollapsingBlockWithClearance(false) |
| { |
| const ComputedStyle& blockStyle = blockFlow->styleRef(); |
| ASSERT(blockFlow->isLayoutView() || blockFlow->parent()); |
| m_canCollapseWithChildren = !blockFlow->createsNewFormattingContext() && !blockFlow->isLayoutFlowThread() && !blockFlow->isLayoutView(); |
| |
| m_canCollapseMarginBeforeWithChildren = m_canCollapseWithChildren && !beforeBorderPadding && blockStyle.marginBeforeCollapse() != MSEPARATE; |
| |
| // If any height other than auto is specified in CSS, then we don't collapse our bottom |
| // margins with our children's margins. To do otherwise would be to risk odd visual |
| // effects when the children overflow out of the parent block and yet still collapse |
| // with it. We also don't collapse if we have any bottom border/padding. |
| m_canCollapseMarginAfterWithChildren = m_canCollapseWithChildren && !afterBorderPadding |
| && (blockStyle.logicalHeight().isAuto() && !blockStyle.logicalHeight().value()) && blockStyle.marginAfterCollapse() != MSEPARATE; |
| |
| m_quirkContainer = blockFlow->isTableCell() || blockFlow->isBody(); |
| |
| m_discardMargin = m_canCollapseMarginBeforeWithChildren && blockFlow->mustDiscardMarginBefore(); |
| |
| m_positiveMargin = (m_canCollapseMarginBeforeWithChildren && !blockFlow->mustDiscardMarginBefore()) ? blockFlow->maxPositiveMarginBefore() : LayoutUnit(); |
| m_negativeMargin = (m_canCollapseMarginBeforeWithChildren && !blockFlow->mustDiscardMarginBefore()) ? blockFlow->maxNegativeMarginBefore() : LayoutUnit(); |
| } |
| |
| LayoutBlockFlow::MarginValues LayoutBlockFlow::marginValuesForChild(LayoutBox& child) const |
| { |
| LayoutUnit childBeforePositive = 0; |
| LayoutUnit childBeforeNegative = 0; |
| LayoutUnit childAfterPositive = 0; |
| LayoutUnit childAfterNegative = 0; |
| |
| LayoutUnit beforeMargin = 0; |
| LayoutUnit afterMargin = 0; |
| |
| LayoutBlockFlow* childLayoutBlockFlow = child.isLayoutBlockFlow() ? toLayoutBlockFlow(&child) : 0; |
| |
| // If the child has the same directionality as we do, then we can just return its |
| // margins in the same direction. |
| if (!child.isWritingModeRoot()) { |
| if (childLayoutBlockFlow) { |
| childBeforePositive = childLayoutBlockFlow->maxPositiveMarginBefore(); |
| childBeforeNegative = childLayoutBlockFlow->maxNegativeMarginBefore(); |
| childAfterPositive = childLayoutBlockFlow->maxPositiveMarginAfter(); |
| childAfterNegative = childLayoutBlockFlow->maxNegativeMarginAfter(); |
| } else { |
| beforeMargin = child.marginBefore(); |
| afterMargin = child.marginAfter(); |
| } |
| } else if (child.isHorizontalWritingMode() == isHorizontalWritingMode()) { |
| // The child has a different directionality. If the child is parallel, then it's just |
| // flipped relative to us. We can use the margins for the opposite edges. |
| if (childLayoutBlockFlow) { |
| childBeforePositive = childLayoutBlockFlow->maxPositiveMarginAfter(); |
| childBeforeNegative = childLayoutBlockFlow->maxNegativeMarginAfter(); |
| childAfterPositive = childLayoutBlockFlow->maxPositiveMarginBefore(); |
| childAfterNegative = childLayoutBlockFlow->maxNegativeMarginBefore(); |
| } else { |
| beforeMargin = child.marginAfter(); |
| afterMargin = child.marginBefore(); |
| } |
| } else { |
| // The child is perpendicular to us, which means its margins don't collapse but are on the |
| // "logical left/right" sides of the child box. We can just return the raw margin in this case. |
| beforeMargin = marginBeforeForChild(child); |
| afterMargin = marginAfterForChild(child); |
| } |
| |
| // Resolve uncollapsing margins into their positive/negative buckets. |
| if (beforeMargin) { |
| if (beforeMargin > 0) |
| childBeforePositive = beforeMargin; |
| else |
| childBeforeNegative = -beforeMargin; |
| } |
| if (afterMargin) { |
| if (afterMargin > 0) |
| childAfterPositive = afterMargin; |
| else |
| childAfterNegative = -afterMargin; |
| } |
| |
| return LayoutBlockFlow::MarginValues(childBeforePositive, childBeforeNegative, childAfterPositive, childAfterNegative); |
| } |
| |
| LayoutUnit LayoutBlockFlow::collapseMargins(LayoutBox& child, MarginInfo& marginInfo, bool childIsSelfCollapsing) |
| { |
| bool childDiscardMarginBefore = mustDiscardMarginBeforeForChild(child); |
| bool childDiscardMarginAfter = mustDiscardMarginAfterForChild(child); |
| |
| // The child discards the before margin when the the after margin has discard in the case of a self collapsing block. |
| childDiscardMarginBefore = childDiscardMarginBefore || (childDiscardMarginAfter && childIsSelfCollapsing); |
| |
| // Get the four margin values for the child and cache them. |
| const LayoutBlockFlow::MarginValues childMargins = marginValuesForChild(child); |
| |
| // Get our max pos and neg top margins. |
| LayoutUnit posTop = childMargins.positiveMarginBefore(); |
| LayoutUnit negTop = childMargins.negativeMarginBefore(); |
| |
| // For self-collapsing blocks, collapse our bottom margins into our |
| // top to get new posTop and negTop values. |
| if (childIsSelfCollapsing) { |
| posTop = std::max(posTop, childMargins.positiveMarginAfter()); |
| negTop = std::max(negTop, childMargins.negativeMarginAfter()); |
| } |
| |
| // See if the top margin is quirky. We only care if this child has |
| // margins that will collapse with us. |
| bool topQuirk = hasMarginBeforeQuirk(&child); |
| |
| if (marginInfo.canCollapseWithMarginBefore()) { |
| if (!childDiscardMarginBefore && !marginInfo.discardMargin()) { |
| // This child is collapsing with the top of the |
| // block. If it has larger margin values, then we need to update |
| // our own maximal values. |
| if (!document().inQuirksMode() || !marginInfo.quirkContainer() || !topQuirk) |
| setMaxMarginBeforeValues(std::max(posTop, maxPositiveMarginBefore()), std::max(negTop, maxNegativeMarginBefore())); |
| |
| // The minute any of the margins involved isn't a quirk, don't |
| // collapse it away, even if the margin is smaller (www.webreference.com |
| // has an example of this, a <dt> with 0.8em author-specified inside |
| // a <dl> inside a <td>. |
| if (!marginInfo.determinedMarginBeforeQuirk() && !topQuirk && (posTop - negTop)) { |
| setHasMarginBeforeQuirk(false); |
| marginInfo.setDeterminedMarginBeforeQuirk(true); |
| } |
| |
| if (!marginInfo.determinedMarginBeforeQuirk() && topQuirk && !marginBefore()) { |
| // We have no top margin and our top child has a quirky margin. |
| // We will pick up this quirky margin and pass it through. |
| // This deals with the <td><div><p> case. |
| // Don't do this for a block that split two inlines though. You do |
| // still apply margins in this case. |
| setHasMarginBeforeQuirk(true); |
| } |
| } else { |
| // The before margin of the container will also discard all the margins it is collapsing with. |
| setMustDiscardMarginBefore(); |
| } |
| } |
| |
| // Once we find a child with discardMarginBefore all the margins collapsing with us must also discard. |
| if (childDiscardMarginBefore) { |
| marginInfo.setDiscardMargin(true); |
| marginInfo.clearMargin(); |
| } |
| |
| if (marginInfo.quirkContainer() && marginInfo.atBeforeSideOfBlock() && (posTop - negTop)) |
| marginInfo.setHasMarginBeforeQuirk(topQuirk); |
| |
| LayoutUnit beforeCollapseLogicalTop = logicalHeight(); |
| LayoutUnit logicalTop = beforeCollapseLogicalTop; |
| |
| LayoutUnit clearanceForSelfCollapsingBlock; |
| LayoutObject* prev = child.previousSibling(); |
| LayoutBlockFlow* previousBlockFlow = prev && prev->isLayoutBlockFlow() && !prev->isFloatingOrOutOfFlowPositioned() ? toLayoutBlockFlow(prev) : 0; |
| // 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 |
| // 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 |
| // 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. |
| if (!marginInfo.canCollapseWithMarginBefore() && previousBlockFlow && marginInfo.lastChildIsSelfCollapsingBlockWithClearance()) { |
| clearanceForSelfCollapsingBlock = marginValuesForChild(*previousBlockFlow).positiveMarginBefore(); |
| setLogicalHeight(logicalHeight() - clearanceForSelfCollapsingBlock); |
| } |
| |
| if (childIsSelfCollapsing) { |
| // 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. |
| // Also, the child's top position equals the logical height of the container. |
| if (!childDiscardMarginBefore && !marginInfo.discardMargin()) { |
| // This child has no height. We need to compute our |
| // position before we collapse the child's margins together, |
| // so that we can get an accurate position for the zero-height block. |
| LayoutUnit collapsedBeforePos = std::max(marginInfo.positiveMargin(), childMargins.positiveMarginBefore()); |
| LayoutUnit collapsedBeforeNeg = std::max(marginInfo.negativeMargin(), childMargins.negativeMarginBefore()); |
| marginInfo.setMargin(collapsedBeforePos, collapsedBeforeNeg); |
| |
| // Now collapse the child's margins together, which means examining our |
| // bottom margin values as well. |
| marginInfo.setPositiveMarginIfLarger(childMargins.positiveMarginAfter()); |
| marginInfo.setNegativeMarginIfLarger(childMargins.negativeMarginAfter()); |
| |
| if (!marginInfo.canCollapseWithMarginBefore()) { |
| // We need to make sure that the position of the self-collapsing block |
| // is correct, since it could have overflowing content |
| // that needs to be positioned correctly (e.g., a block that |
| // had a specified height of 0 but that actually had subcontent). |
| logicalTop = logicalHeight() + collapsedBeforePos - collapsedBeforeNeg; |
| } |
| } |
| } else { |
| if (mustSeparateMarginBeforeForChild(child)) { |
| ASSERT(!marginInfo.discardMargin() || (marginInfo.discardMargin() && !marginInfo.margin())); |
| // If we are at the before side of the block and we collapse, ignore the computed margin |
| // and just add the child margin to the container height. This will correctly position |
| // the child inside the container. |
| LayoutUnit separateMargin = !marginInfo.canCollapseWithMarginBefore() ? marginInfo.margin() : LayoutUnit(); |
| setLogicalHeight(logicalHeight() + separateMargin + marginBeforeForChild(child)); |
| logicalTop = logicalHeight(); |
| } else if (!marginInfo.discardMargin() && (!marginInfo.atBeforeSideOfBlock() |
| || (!marginInfo.canCollapseMarginBeforeWithChildren() |
| && (!document().inQuirksMode() || !marginInfo.quirkContainer() || !marginInfo.hasMarginBeforeQuirk())))) { |
| // We're collapsing with a previous sibling's margins and not |
| // with the top of the block. |
| setLogicalHeight(logicalHeight() + std::max(marginInfo.positiveMargin(), posTop) - std::max(marginInfo.negativeMargin(), negTop)); |
| logicalTop = logicalHeight(); |
| } |
| |
| marginInfo.setDiscardMargin(childDiscardMarginAfter); |
| |
| if (!marginInfo.discardMargin()) { |
| marginInfo.setPositiveMargin(childMargins.positiveMarginAfter()); |
| marginInfo.setNegativeMargin(childMargins.negativeMarginAfter()); |
| } else { |
| marginInfo.clearMargin(); |
| } |
| |
| if (marginInfo.margin()) |
| marginInfo.setHasMarginAfterQuirk(hasMarginAfterQuirk(&child)); |
| } |
| |
| // If margins would pull us past the top of the next page, then we need to pull back and pretend like the margins |
| // collapsed into the page edge. |
| LayoutState* layoutState = view()->layoutState(); |
| if (layoutState->isPaginated() && isPageLogicalHeightKnown(beforeCollapseLogicalTop) && logicalTop > beforeCollapseLogicalTop) { |
| LayoutUnit oldLogicalTop = logicalTop; |
| logicalTop = std::min(logicalTop, nextPageLogicalTop(beforeCollapseLogicalTop)); |
| setLogicalHeight(logicalHeight() + (logicalTop - oldLogicalTop)); |
| } |
| |
| if (previousBlockFlow) { |
| // 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 |
| // any floats from the parent will now overhang. |
| LayoutUnit oldLogicalHeight = logicalHeight(); |
| setLogicalHeight(logicalTop); |
| if (!previousBlockFlow->avoidsFloats() && (previousBlockFlow->logicalTop() + previousBlockFlow->lowestFloatLogicalBottom()) > logicalTop) |
| addOverhangingFloats(previousBlockFlow, false); |
| setLogicalHeight(oldLogicalHeight); |
| |
| // If |child|'s previous sibling is a self-collapsing block that cleared a float and margin collapsing resulted in |child| moving up |
| // 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 |
| // floats in the parent that overhang |child|'s new logical top. |
| bool logicalTopIntrudesIntoFloat = clearanceForSelfCollapsingBlock > 0 && logicalTop < beforeCollapseLogicalTop; |
| if (logicalTopIntrudesIntoFloat && containsFloats() && !child.avoidsFloats() && lowestFloatLogicalBottom() > logicalTop) |
| child.setNeedsLayoutAndFullPaintInvalidation(LayoutInvalidationReason::AncestorMarginCollapsing); |
| } |
| |
| return logicalTop; |
| } |
| |
| void LayoutBlockFlow::adjustPositionedBlock(LayoutBox& child, const MarginInfo& marginInfo) |
| { |
| LayoutUnit logicalTop = logicalHeight(); |
| updateStaticInlinePositionForChild(child, logicalTop); |
| |
| if (!marginInfo.canCollapseWithMarginBefore()) { |
| // Positioned blocks don't collapse margins, so add the margin provided by |
| // the container now. The child's own margin is added later when calculating its logical top. |
| LayoutUnit collapsedBeforePos = marginInfo.positiveMargin(); |
| LayoutUnit collapsedBeforeNeg = marginInfo.negativeMargin(); |
| logicalTop += collapsedBeforePos - collapsedBeforeNeg; |
| } |
| |
| DeprecatedPaintLayer* childLayer = child.layer(); |
| if (childLayer->staticBlockPosition() != logicalTop) |
| childLayer->setStaticBlockPosition(logicalTop); |
| } |
| |
| LayoutUnit LayoutBlockFlow::clearFloatsIfNeeded(LayoutBox& child, MarginInfo& marginInfo, LayoutUnit oldTopPosMargin, LayoutUnit oldTopNegMargin, LayoutUnit yPos, bool childIsSelfCollapsing) |
| { |
| LayoutUnit heightIncrease = getClearDelta(&child, yPos); |
| marginInfo.setLastChildIsSelfCollapsingBlockWithClearance(false); |
| |
| if (!heightIncrease) |
| return yPos; |
| |
| if (childIsSelfCollapsing) { |
| marginInfo.setLastChildIsSelfCollapsingBlockWithClearance(true); |
| bool childDiscardMargin = mustDiscardMarginBeforeForChild(child) || mustDiscardMarginAfterForChild(child); |
| marginInfo.setDiscardMargin(childDiscardMargin); |
| |
| // For self-collapsing blocks that clear, they can still collapse their |
| // margins with following siblings. Reset the current margins to represent |
| // the self-collapsing block's margins only. |
| // If DISCARD is specified for -webkit-margin-collapse, reset the margin values. |
| LayoutBlockFlow::MarginValues childMargins = marginValuesForChild(child); |
| if (!childDiscardMargin) { |
| marginInfo.setPositiveMargin(std::max(childMargins.positiveMarginBefore(), childMargins.positiveMarginAfter())); |
| marginInfo.setNegativeMargin(std::max(childMargins.negativeMarginBefore(), childMargins.negativeMarginAfter())); |
| } else { |
| marginInfo.clearMargin(); |
| } |
| |
| // CSS2.1 states: |
| // "If the top and bottom margins of an element with clearance are adjoining, its margins collapse with |
| // the adjoining margins of following siblings but that resulting margin does not collapse with the bottom margin of the parent block." |
| // So the parent's bottom margin cannot collapse through this block or any subsequent self-collapsing blocks. Set a bit to ensure |
| // this happens; it will get reset if we encounter an in-flow sibling that is not self-collapsing. |
| marginInfo.setCanCollapseMarginAfterWithLastChild(false); |
| |
| // 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 |
| // its own at the correct vertical position. If subsequent siblings attempt to collapse with |child|'s margins in |collapseMargins| we will |
| // 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 |
| // margins can collapse at the correct vertical position. |
| // 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 |
| // (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], |
| // i.e., clearance = [height of float] - margin-top". |
| setLogicalHeight(child.logicalTop() + childMargins.negativeMarginBefore()); |
| } else { |
| // Increase our height by the amount we had to clear. |
| setLogicalHeight(logicalHeight() + heightIncrease); |
| } |
| |
| if (marginInfo.canCollapseWithMarginBefore()) { |
| // We can no longer collapse with the top of the block since a clear |
| // occurred. The empty blocks collapse into the cleared block. |
| setMaxMarginBeforeValues(oldTopPosMargin, oldTopNegMargin); |
| marginInfo.setAtBeforeSideOfBlock(false); |
| |
| // In case the child discarded the before margin of the block we need to reset the mustDiscardMarginBefore flag to the initial value. |
| setMustDiscardMarginBefore(style()->marginBeforeCollapse() == MDISCARD); |
| } |
| |
| return yPos + heightIncrease; |
| } |
| |
| void LayoutBlockFlow::setCollapsedBottomMargin(const MarginInfo& marginInfo) |
| { |
| if (marginInfo.canCollapseWithMarginAfter() && !marginInfo.canCollapseWithMarginBefore()) { |
| // 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. |
| // Don't update the max margin values because we won't need them anyway. |
| if (marginInfo.discardMargin()) { |
| setMustDiscardMarginAfter(); |
| return; |
| } |
| |
| // Update our max pos/neg bottom margins, since we collapsed our bottom margins |
| // with our children. |
| setMaxMarginAfterValues(std::max(maxPositiveMarginAfter(), marginInfo.positiveMargin()), std::max(maxNegativeMarginAfter(), marginInfo.negativeMargin())); |
| |
| if (!marginInfo.hasMarginAfterQuirk()) |
| setHasMarginAfterQuirk(false); |
| |
| if (marginInfo.hasMarginAfterQuirk() && !marginAfter()) { |
| // We have no bottom margin and our last child has a quirky margin. |
| // We will pick up this quirky margin and pass it through. |
| // This deals with the <td><div><p> case. |
| setHasMarginAfterQuirk(true); |
| } |
| } |
| } |
| |
| void LayoutBlockFlow::marginBeforeEstimateForChild(LayoutBox& child, LayoutUnit& positiveMarginBefore, LayoutUnit& negativeMarginBefore, bool& discardMarginBefore) const |
| { |
| // Give up if in quirks mode and we're a body/table cell and the top margin of the child box is quirky. |
| // Give up if the child specified -webkit-margin-collapse: separate that prevents collapsing. |
| // FIXME: Use writing mode independent accessor for marginBeforeCollapse. |
| if ((document().inQuirksMode() && hasMarginBeforeQuirk(&child) && (isTableCell() || isBody())) || child.style()->marginBeforeCollapse() == MSEPARATE) |
| return; |
| |
| // The margins are discarded by a child that specified -webkit-margin-collapse: discard. |
| // FIXME: Use writing mode independent accessor for marginBeforeCollapse. |
| if (child.style()->marginBeforeCollapse() == MDISCARD) { |
| positiveMarginBefore = 0; |
| negativeMarginBefore = 0; |
| discardMarginBefore = true; |
| return; |
| } |
| |
| LayoutUnit beforeChildMargin = marginBeforeForChild(child); |
| positiveMarginBefore = std::max(positiveMarginBefore, beforeChildMargin); |
| negativeMarginBefore = std::max(negativeMarginBefore, -beforeChildMargin); |
| |
| if (!child.isLayoutBlockFlow()) |
| return; |
| |
| LayoutBlockFlow* childBlockFlow = toLayoutBlockFlow(&child); |
| if (childBlockFlow->childrenInline() || childBlockFlow->isWritingModeRoot()) |
| return; |
| |
| MarginInfo childMarginInfo(childBlockFlow, childBlockFlow->borderBefore() + childBlockFlow->paddingBefore(), childBlockFlow->borderAfter() + childBlockFlow->paddingAfter()); |
| if (!childMarginInfo.canCollapseMarginBeforeWithChildren()) |
| return; |
| |
| LayoutBox* grandchildBox = childBlockFlow->firstChildBox(); |
| for ( ; grandchildBox; grandchildBox = grandchildBox->nextSiblingBox()) { |
| if (!grandchildBox->isFloatingOrOutOfFlowPositioned() && !grandchildBox->isColumnSpanAll()) |
| break; |
| } |
| |
| if (!grandchildBox) |
| return; |
| |
| // Make sure to update the block margins now for the grandchild box so that we're looking at current values. |
| if (grandchildBox->needsLayout()) { |
| grandchildBox->computeAndSetBlockDirectionMargins(this); |
| if (grandchildBox->isLayoutBlock()) { |
| LayoutBlock* grandchildBlock = toLayoutBlock(grandchildBox); |
| grandchildBlock->setHasMarginBeforeQuirk(grandchildBox->style()->hasMarginBeforeQuirk()); |
| grandchildBlock->setHasMarginAfterQuirk(grandchildBox->style()->hasMarginAfterQuirk()); |
| } |
| } |
| |
| // If we have a 'clear' value but also have a margin we may not actually require clearance to move past any floats. |
| // If that's the case we want to be sure we estimate the correct position including margins after any floats rather |
| // than use 'clearance' later which could give us the wrong position. |
| if (grandchildBox->style()->clear() != CNONE && childBlockFlow->marginBeforeForChild(*grandchildBox) == 0) |
| return; |
| |
| // Collapse the margin of the grandchild box with our own to produce an estimate. |
| childBlockFlow->marginBeforeEstimateForChild(*grandchildBox, positiveMarginBefore, negativeMarginBefore, discardMarginBefore); |
| } |
| |
| LayoutUnit LayoutBlockFlow::estimateLogicalTopPosition(LayoutBox& child, const MarginInfo& marginInfo, LayoutUnit& estimateWithoutPagination) |
| { |
| // FIXME: We need to eliminate the estimation of vertical position, because when it's wrong we sometimes trigger a pathological |
| // relayout if there are intruding floats. |
| LayoutUnit logicalTopEstimate = logicalHeight(); |
| if (!marginInfo.canCollapseWithMarginBefore()) { |
| LayoutUnit positiveMarginBefore = 0; |
| LayoutUnit negativeMarginBefore = 0; |
| bool discardMarginBefore = false; |
| if (child.selfNeedsLayout()) { |
| // Try to do a basic estimation of how the collapse is going to go. |
| marginBeforeEstimateForChild(child, positiveMarginBefore, negativeMarginBefore, discardMarginBefore); |
| } else { |
| // Use the cached collapsed margin values from a previous layout. Most of the time they |
| // will be right. |
| LayoutBlockFlow::MarginValues marginValues = marginValuesForChild(child); |
| positiveMarginBefore = std::max(positiveMarginBefore, marginValues.positiveMarginBefore()); |
| negativeMarginBefore = std::max(negativeMarginBefore, marginValues.negativeMarginBefore()); |
| discardMarginBefore = mustDiscardMarginBeforeForChild(child); |
| } |
| |
| // Collapse the result with our current margins. |
| if (!discardMarginBefore) |
| logicalTopEstimate += std::max(marginInfo.positiveMargin(), positiveMarginBefore) - std::max(marginInfo.negativeMargin(), negativeMarginBefore); |
| } |
| |
| // Adjust logicalTopEstimate down to the next page if the margins are so large that we don't fit on the current |
| // page. |
| LayoutState* layoutState = view()->layoutState(); |
| if (layoutState->isPaginated() && isPageLogicalHeightKnown(logicalHeight()) && logicalTopEstimate > logicalHeight()) |
| logicalTopEstimate = std::min(logicalTopEstimate, nextPageLogicalTop(logicalHeight())); |
| |
| logicalTopEstimate += getClearDelta(&child, logicalTopEstimate); |
| |
| estimateWithoutPagination = logicalTopEstimate; |
| |
| if (layoutState->isPaginated()) { |
| // If the object has a page or column break value of "before", then we should shift to the top of the next page. |
| logicalTopEstimate = applyBeforeBreak(child, logicalTopEstimate); |
| |
| // For replaced elements and scrolled elements, we want to shift them to the next page if they don't fit on the current one. |
| logicalTopEstimate = adjustForUnsplittableChild(child, logicalTopEstimate); |
| |
| if (!child.selfNeedsLayout() && child.isLayoutBlockFlow()) |
| logicalTopEstimate += toLayoutBlockFlow(&child)->paginationStrut(); |
| } |
| |
| return logicalTopEstimate; |
| } |
| |
| void LayoutBlockFlow::adjustFloatingBlock(const MarginInfo& marginInfo) |
| { |
| // The float should be positioned taking into account the bottom margin |
| // of the previous flow. We add that margin into the height, get the |
| // float positioned properly, and then subtract the margin out of the |
| // height again. In the case of self-collapsing blocks, we always just |
| // use the top margins, since the self-collapsing block collapsed its |
| // own bottom margin into its top margin. |
| // |
| // Note also that the previous flow may collapse its margin into the top of |
| // our block. If this is the case, then we do not add the margin in to our |
| // height when computing the position of the float. This condition can be tested |
| // for by simply calling canCollapseWithMarginBefore. See |
| // http://www.hixie.ch/tests/adhoc/css/box/block/margin-collapse/046.html for |
| // an example of this scenario. |
| LayoutUnit marginOffset = marginInfo.canCollapseWithMarginBefore() ? LayoutUnit() : marginInfo.margin(); |
| setLogicalHeight(logicalHeight() + marginOffset); |
| positionNewFloats(); |
| setLogicalHeight(logicalHeight() - marginOffset); |
| } |
| |
| void LayoutBlockFlow::handleAfterSideOfBlock(LayoutBox* lastChild, LayoutUnit beforeSide, LayoutUnit afterSide, MarginInfo& marginInfo) |
| { |
| marginInfo.setAtAfterSideOfBlock(true); |
| |
| // If our last child was a self-collapsing block with clearance then our logical height is flush with the |
| // bottom edge of the float that the child clears. The correct vertical position for the margin-collapsing we want |
| // to perform now is at the child's margin-top - so adjust our height to that position. |
| if (marginInfo.lastChildIsSelfCollapsingBlockWithClearance()) { |
| ASSERT(lastChild); |
| setLogicalHeight(logicalHeight() - marginValuesForChild(*lastChild).positiveMarginBefore()); |
| } |
| |
| if (marginInfo.canCollapseMarginAfterWithChildren() && !marginInfo.canCollapseMarginAfterWithLastChild()) |
| marginInfo.setCanCollapseMarginAfterWithChildren(false); |
| |
| // If we can't collapse with children then go ahead and add in the bottom margin. |
| if (!marginInfo.discardMargin() && (!marginInfo.canCollapseWithMarginAfter() && !marginInfo.canCollapseWithMarginBefore() |
| && (!document().inQuirksMode() || !marginInfo.quirkContainer() || !marginInfo.hasMarginAfterQuirk()))) |
| setLogicalHeight(logicalHeight() + marginInfo.margin()); |
| |
| // Now add in our bottom border/padding. |
| setLogicalHeight(logicalHeight() + afterSide); |
| |
| // Negative margins can cause our height to shrink below our minimal height (border/padding). |
| // If this happens, ensure that the computed height is increased to the minimal height. |
| setLogicalHeight(std::max(logicalHeight(), beforeSide + afterSide)); |
| |
| // Update our bottom collapsed margin info. |
| setCollapsedBottomMargin(marginInfo); |
| } |
| |
| void LayoutBlockFlow::setMustDiscardMarginBefore(bool value) |
| { |
| if (style()->marginBeforeCollapse() == MDISCARD) { |
| ASSERT(value); |
| return; |
| } |
| |
| if (!m_rareData && !value) |
| return; |
| |
| if (!m_rareData) |
| m_rareData = adoptPtr(new LayoutBlockFlowRareData(this)); |
| |
| m_rareData->m_discardMarginBefore = value; |
| } |
| |
| void LayoutBlockFlow::setMustDiscardMarginAfter(bool value) |
| { |
| if (style()->marginAfterCollapse() == MDISCARD) { |
| ASSERT(value); |
| return; |
| } |
| |
| if (!m_rareData && !value) |
| return; |
| |
| if (!m_rareData) |
| m_rareData = adoptPtr(new LayoutBlockFlowRareData(this)); |
| |
| m_rareData->m_discardMarginAfter = value; |
| } |
| |
| bool LayoutBlockFlow::mustDiscardMarginBefore() const |
| { |
| return style()->marginBeforeCollapse() == MDISCARD || (m_rareData && m_rareData->m_discardMarginBefore); |
| } |
| |
| bool LayoutBlockFlow::mustDiscardMarginAfter() const |
| { |
| return style()->marginAfterCollapse() == MDISCARD || (m_rareData && m_rareData->m_discardMarginAfter); |
| } |
| |
| bool LayoutBlockFlow::mustDiscardMarginBeforeForChild(const LayoutBox& child) const |
| { |
| ASSERT(!child.selfNeedsLayout()); |
| if (!child.isWritingModeRoot()) |
| return child.isLayoutBlockFlow() ? toLayoutBlockFlow(&child)->mustDiscardMarginBefore() : (child.style()->marginBeforeCollapse() == MDISCARD); |
| if (child.isHorizontalWritingMode() == isHorizontalWritingMode()) |
| return child.isLayoutBlockFlow() ? toLayoutBlockFlow(&child)->mustDiscardMarginAfter() : (child.style()->marginAfterCollapse() == MDISCARD); |
| |
| // FIXME: We return false here because the implementation is not geometrically complete. We have values only for before/after, not start/end. |
| // In case the boxes are perpendicular we assume the property is not specified. |
| return false; |
| } |
| |
| bool LayoutBlockFlow::mustDiscardMarginAfterForChild(const LayoutBox& child) const |
| { |
| ASSERT(!child.selfNeedsLayout()); |
| if (!child.isWritingModeRoot()) |
| return child.isLayoutBlockFlow() ? toLayoutBlockFlow(&child)->mustDiscardMarginAfter() : (child.style()->marginAfterCollapse() == MDISCARD); |
| if (child.isHorizontalWritingMode() == isHorizontalWritingMode()) |
| return child.isLayoutBlockFlow() ? toLayoutBlockFlow(&child)->mustDiscardMarginBefore() : (child.style()->marginBeforeCollapse() == MDISCARD); |
| |
| // FIXME: See |mustDiscardMarginBeforeForChild| above. |
| return false; |
| } |
| |
| void LayoutBlockFlow::setMaxMarginBeforeValues(LayoutUnit pos, LayoutUnit neg) |
| { |
| if (!m_rareData) { |
| if (pos == LayoutBlockFlowRareData::positiveMarginBeforeDefault(this) && neg == LayoutBlockFlowRareData::negativeMarginBeforeDefault(this)) |
| return; |
| m_rareData = adoptPtr(new LayoutBlockFlowRareData(this)); |
| } |
| m_rareData->m_margins.setPositiveMarginBefore(pos); |
| m_rareData->m_margins.setNegativeMarginBefore(neg); |
| } |
| |
| void LayoutBlockFlow::setMaxMarginAfterValues(LayoutUnit pos, LayoutUnit neg) |
| { |
| if (!m_rareData) { |
| if (pos == LayoutBlockFlowRareData::positiveMarginAfterDefault(this) && neg == LayoutBlockFlowRareData::negativeMarginAfterDefault(this)) |
| return; |
| m_rareData = adoptPtr(new LayoutBlockFlowRareData(this)); |
| } |
| m_rareData->m_margins.setPositiveMarginAfter(pos); |
| m_rareData->m_margins.setNegativeMarginAfter(neg); |
| } |
| |
| bool LayoutBlockFlow::mustSeparateMarginBeforeForChild(const LayoutBox& child) const |
| { |
| ASSERT(!child.selfNeedsLayout()); |
| const ComputedStyle& childStyle = child.styleRef(); |
| if (!child.isWritingModeRoot()) |
| return childStyle.marginBeforeCollapse() == MSEPARATE; |
| if (child.isHorizontalWritingMode() == isHorizontalWritingMode()) |
| return childStyle.marginAfterCollapse() == MSEPARATE; |
| |
| // FIXME: See |mustDiscardMarginBeforeForChild| above. |
| return false; |
| } |
| |
| bool LayoutBlockFlow::mustSeparateMarginAfterForChild(const LayoutBox& child) const |
| { |
| ASSERT(!child.selfNeedsLayout()); |
| const ComputedStyle& childStyle = child.styleRef(); |
| if (!child.isWritingModeRoot()) |
| return childStyle.marginAfterCollapse() == MSEPARATE; |
| if (child.isHorizontalWritingMode() == isHorizontalWritingMode()) |
| return childStyle.marginBeforeCollapse() == MSEPARATE; |
| |
| // FIXME: See |mustDiscardMarginBeforeForChild| above. |
| return false; |
| } |
| |
| LayoutUnit LayoutBlockFlow::applyBeforeBreak(LayoutBox& child, LayoutUnit logicalOffset) |
| { |
| // FIXME: Add page break checking here when we support printing. |
| LayoutFlowThread* flowThread = flowThreadContainingBlock(); |
| bool checkColumnBreaks = flowThread; |
| bool checkPageBreaks = !checkColumnBreaks && view()->layoutState()->pageLogicalHeight(); // FIXME: Once columns can print we have to check this. |
| bool checkBeforeAlways = (checkColumnBreaks && child.style()->columnBreakBefore() == PBALWAYS) |
| || (checkPageBreaks && child.style()->pageBreakBefore() == PBALWAYS); |
| if (checkBeforeAlways && inNormalFlow(&child)) { |
| if (checkColumnBreaks) { |
| LayoutUnit offsetBreakAdjustment = 0; |
| if (flowThread->addForcedColumnBreak(offsetFromLogicalTopOfFirstPage() + logicalOffset, &child, true, &offsetBreakAdjustment)) |
| return logicalOffset + offsetBreakAdjustment; |
| } |
| return nextPageLogicalTop(logicalOffset, IncludePageBoundary); |
| } |
| return logicalOffset; |
| } |
| |
| LayoutUnit LayoutBlockFlow::applyAfterBreak(LayoutBox& child, LayoutUnit logicalOffset, MarginInfo& marginInfo) |
| { |
| // FIXME: Add page break checking here when we support printing. |
| LayoutFlowThread* flowThread = flowThreadContainingBlock(); |
| bool checkColumnBreaks = flowThread; |
| bool checkPageBreaks = !checkColumnBreaks && view()->layoutState()->pageLogicalHeight(); // FIXME: Once columns can print we have to check this. |
| bool checkAfterAlways = (checkColumnBreaks && child.style()->columnBreakAfter() == PBALWAYS) |
| || (checkPageBreaks && child.style()->pageBreakAfter() == PBALWAYS); |
| if (checkAfterAlways && inNormalFlow(&child)) { |
| // So our margin doesn't participate in the next collapsing steps. |
| marginInfo.clearMargin(); |
| |
| if (checkColumnBreaks) { |
| LayoutUnit offsetBreakAdjustment = 0; |
| if (flowThread->addForcedColumnBreak(offsetFromLogicalTopOfFirstPage() + logicalOffset, &child, false, &offsetBreakAdjustment)) |
| return logicalOffset + offsetBreakAdjustment; |
| } |
| return nextPageLogicalTop(logicalOffset, IncludePageBoundary); |
| } |
| return logicalOffset; |
| } |
| |
| void LayoutBlockFlow::addOverflowFromFloats() |
| { |
| if (!m_floatingObjects) |
| return; |
| |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) { |
| const FloatingObject& floatingObject = *it->get(); |
| if (floatingObject.isDescendant()) |
| addOverflowFromChild(floatingObject.layoutObject(), LayoutSize(xPositionForFloatIncludingMargin(floatingObject), yPositionForFloatIncludingMargin(floatingObject))); |
| } |
| } |
| |
| void LayoutBlockFlow::computeOverflow(LayoutUnit oldClientAfterEdge, bool recomputeFloats) |
| { |
| LayoutBlock::computeOverflow(oldClientAfterEdge, recomputeFloats); |
| if (recomputeFloats || createsNewFormattingContext() || hasSelfPaintingLayer()) |
| addOverflowFromFloats(); |
| } |
| |
| RootInlineBox* LayoutBlockFlow::createAndAppendRootInlineBox() |
| { |
| RootInlineBox* rootBox = createRootInlineBox(); |
| m_lineBoxes.appendLineBox(rootBox); |
| |
| return rootBox; |
| } |
| |
| void LayoutBlockFlow::deleteLineBoxTree() |
| { |
| if (containsFloats()) |
| m_floatingObjects->clearLineBoxTreePointers(); |
| |
| m_lineBoxes.deleteLineBoxTree(); |
| } |
| |
| void LayoutBlockFlow::markAllDescendantsWithFloatsForLayout(LayoutBox* floatToRemove, bool inLayout) |
| { |
| if (!everHadLayout() && !containsFloats()) |
| return; |
| |
| if (m_descendantsWithFloatsMarkedForLayout && !floatToRemove) |
| return; |
| m_descendantsWithFloatsMarkedForLayout |= !floatToRemove; |
| |
| MarkingBehavior markParents = inLayout ? MarkOnlyThis : MarkContainerChain; |
| setChildNeedsLayout(markParents); |
| |
| if (floatToRemove) |
| removeFloatingObject(floatToRemove); |
| |
| // Iterate over our children and mark them as needed. |
| if (!childrenInline() || floatToRemove) { |
| for (LayoutObject* child = firstChild(); child; child = child->nextSibling()) { |
| if ((!floatToRemove && child->isFloatingOrOutOfFlowPositioned()) || !child->isLayoutBlock()) |
| continue; |
| if (!child->isLayoutBlockFlow()) { |
| LayoutBlock* childBlock = toLayoutBlock(child); |
| if (childBlock->shrinkToAvoidFloats() && childBlock->everHadLayout()) |
| childBlock->setChildNeedsLayout(markParents); |
| continue; |
| } |
| LayoutBlockFlow* childBlockFlow = toLayoutBlockFlow(child); |
| if ((floatToRemove ? childBlockFlow->containsFloat(floatToRemove) : childBlockFlow->containsFloats()) || childBlockFlow->shrinkToAvoidFloats()) |
| childBlockFlow->markAllDescendantsWithFloatsForLayout(floatToRemove, inLayout); |
| } |
| } |
| } |
| |
| void LayoutBlockFlow::markSiblingsWithFloatsForLayout(LayoutBox* floatToRemove) |
| { |
| if (!m_floatingObjects) |
| return; |
| |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| |
| for (LayoutObject* next = nextSibling(); next; next = next->nextSibling()) { |
| if (!next->isLayoutBlockFlow() || (!floatToRemove && (next->isFloatingOrOutOfFlowPositioned() || toLayoutBlockFlow(next)->avoidsFloats()))) |
| continue; |
| |
| LayoutBlockFlow* nextBlock = toLayoutBlockFlow(next); |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) { |
| LayoutBox* floatingBox = (*it)->layoutObject(); |
| if (floatToRemove && floatingBox != floatToRemove) |
| continue; |
| if (nextBlock->containsFloat(floatingBox)) |
| nextBlock->markAllDescendantsWithFloatsForLayout(floatingBox); |
| } |
| } |
| } |
| |
| LayoutUnit LayoutBlockFlow::getClearDelta(LayoutBox* child, LayoutUnit logicalTop) |
| { |
| // There is no need to compute clearance if we have no floats. |
| if (!containsFloats()) |
| return LayoutUnit(); |
| |
| // At least one float is present. We need to perform the clearance computation. |
| bool clearSet = child->style()->clear() != CNONE; |
| LayoutUnit logicalBottom = 0; |
| switch (child->style()->clear()) { |
| case CNONE: |
| break; |
| case CLEFT: |
| logicalBottom = lowestFloatLogicalBottom(FloatingObject::FloatLeft); |
| break; |
| case CRIGHT: |
| logicalBottom = lowestFloatLogicalBottom(FloatingObject::FloatRight); |
| break; |
| case CBOTH: |
| logicalBottom = lowestFloatLogicalBottom(); |
| break; |
| } |
| |
| // 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). |
| LayoutUnit result = clearSet ? std::max<LayoutUnit>(0, logicalBottom - logicalTop) : LayoutUnit(); |
| if (!result && child->avoidsFloats()) { |
| LayoutUnit newLogicalTop = logicalTop; |
| LayoutRect borderBox = child->borderBoxRect(); |
| LayoutUnit childLogicalWidthAtOldLogicalTopOffset = isHorizontalWritingMode() ? borderBox.width() : borderBox.height(); |
| while (true) { |
| LayoutUnit availableLogicalWidthAtNewLogicalTopOffset = availableLogicalWidthForLine(newLogicalTop, false, logicalHeightForChild(*child)); |
| if (availableLogicalWidthAtNewLogicalTopOffset == availableLogicalWidthForContent()) |
| return newLogicalTop - logicalTop; |
| |
| LogicalExtentComputedValues computedValues; |
| child->logicalExtentAfterUpdatingLogicalWidth(newLogicalTop, computedValues); |
| LayoutUnit childLogicalWidthAtNewLogicalTopOffset = computedValues.m_extent; |
| |
| if (childLogicalWidthAtNewLogicalTopOffset <= availableLogicalWidthAtNewLogicalTopOffset) { |
| // Even though we may not be moving, if the logical width did shrink because of the presence of new floats, then |
| // we need to force a relayout as though we shifted. This happens because of the dynamic addition of overhanging floats |
| // from previous siblings when negative margins exist on a child (see the addOverhangingFloats call at the end of collapseMargins). |
| if (childLogicalWidthAtOldLogicalTopOffset != childLogicalWidthAtNewLogicalTopOffset) |
| child->setChildNeedsLayout(MarkOnlyThis); |
| return newLogicalTop - logicalTop; |
| } |
| |
| newLogicalTop = nextFloatLogicalBottomBelow(newLogicalTop); |
| ASSERT(newLogicalTop >= logicalTop); |
| if (newLogicalTop < logicalTop) |
| break; |
| } |
| ASSERT_NOT_REACHED(); |
| } |
| return result; |
| } |
| |
| void LayoutBlockFlow::createFloatingObjects() |
| { |
| m_floatingObjects = adoptPtr(new FloatingObjects(this, isHorizontalWritingMode())); |
| } |
| |
| void LayoutBlockFlow::styleWillChange(StyleDifference diff, const ComputedStyle& newStyle) |
| { |
| const ComputedStyle* oldStyle = style(); |
| s_canPropagateFloatIntoSibling = oldStyle ? !isFloatingOrOutOfFlowPositioned() && !avoidsFloats() : false; |
| if (oldStyle && parent() && diff.needsFullLayout() && oldStyle->position() != newStyle.position() |
| && containsFloats() && !isFloating() && !isOutOfFlowPositioned() && newStyle.hasOutOfFlowPosition()) |
| markAllDescendantsWithFloatsForLayout(); |
| |
| LayoutBlock::styleWillChange(diff, newStyle); |
| } |
| |
| void LayoutBlockFlow::styleDidChange(StyleDifference diff, const ComputedStyle* oldStyle) |
| { |
| LayoutBlock::styleDidChange(diff, oldStyle); |
| |
| // After our style changed, if we lose our ability to propagate floats into next sibling |
| // blocks, then we need to find the top most parent containing that overhanging float and |
| // then mark its descendants with floats for layout and clear all floats from its next |
| // sibling blocks that exist in our floating objects list. See bug 56299 and 62875. |
| bool canPropagateFloatIntoSibling = !isFloatingOrOutOfFlowPositioned() && !avoidsFloats(); |
| if (diff.needsFullLayout() && s_canPropagateFloatIntoSibling && !canPropagateFloatIntoSibling && hasOverhangingFloats()) { |
| LayoutBlockFlow* parentBlockFlow = this; |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| |
| for (LayoutObject* curr = parent(); curr && !curr->isLayoutView(); curr = curr->parent()) { |
| if (curr->isLayoutBlockFlow()) { |
| LayoutBlockFlow* currBlock = toLayoutBlockFlow(curr); |
| |
| if (currBlock->hasOverhangingFloats()) { |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) { |
| LayoutBox* layoutBox = (*it)->layoutObject(); |
| if (currBlock->hasOverhangingFloat(layoutBox)) { |
| parentBlockFlow = currBlock; |
| break; |
| } |
| } |
| } |
| } |
| } |
| |
| parentBlockFlow->markAllDescendantsWithFloatsForLayout(); |
| parentBlockFlow->markSiblingsWithFloatsForLayout(); |
| } |
| |
| if (diff.needsFullLayout() || !oldStyle) |
| createOrDestroyMultiColumnFlowThreadIfNeeded(oldStyle); |
| if (oldStyle) { |
| if (LayoutMultiColumnFlowThread* flowThread = multiColumnFlowThread()) { |
| if (!style()->columnRuleEquivalent(oldStyle)) { |
| // Column rules are painted by anonymous column set children of the multicol |
| // container. We need to notify them. |
| flowThread->columnRuleStyleDidChange(); |
| } |
| } |
| } |
| } |
| |
| void LayoutBlockFlow::updateBlockChildDirtyBitsBeforeLayout(bool relayoutChildren, LayoutBox& child) |
| { |
| if (child.isLayoutMultiColumnSpannerPlaceholder()) |
| toLayoutMultiColumnSpannerPlaceholder(child).markForLayoutIfObjectInFlowThreadNeedsLayout(); |
| LayoutBlock::updateBlockChildDirtyBitsBeforeLayout(relayoutChildren, child); |
| } |
| |
| void LayoutBlockFlow::updateStaticInlinePositionForChild(LayoutBox& child, LayoutUnit logicalTop) |
| { |
| if (child.style()->isOriginalDisplayInlineType()) |
| setStaticInlinePositionForChild(child, startAlignedOffsetForLine(logicalTop, false)); |
| else |
| setStaticInlinePositionForChild(child, startOffsetForContent()); |
| } |
| |
| void LayoutBlockFlow::setStaticInlinePositionForChild(LayoutBox& child, LayoutUnit inlinePosition) |
| { |
| child.layer()->setStaticInlinePosition(inlinePosition); |
| } |
| |
| void LayoutBlockFlow::addChild(LayoutObject* newChild, LayoutObject* beforeChild) |
| { |
| if (LayoutMultiColumnFlowThread* flowThread = multiColumnFlowThread()) { |
| if (beforeChild == flowThread) |
| beforeChild = flowThread->firstChild(); |
| ASSERT(!beforeChild || beforeChild->isDescendantOf(flowThread)); |
| flowThread->addChild(newChild, beforeChild); |
| return; |
| } |
| LayoutBlock::addChild(newChild, beforeChild); |
| } |
| |
| void LayoutBlockFlow::moveAllChildrenIncludingFloatsTo(LayoutBlock* toBlock, bool fullRemoveInsert) |
| { |
| LayoutBlockFlow* toBlockFlow = toLayoutBlockFlow(toBlock); |
| moveAllChildrenTo(toBlockFlow, fullRemoveInsert); |
| |
| // When a portion of the layout tree is being detached, anonymous blocks |
| // will be combined as their children are deleted. In this process, the |
| // anonymous block later in the tree is merged into the one preceeding it. |
| // It can happen that the later block (this) contains floats that the |
| // previous block (toBlockFlow) did not contain, and thus are not in the |
| // floating objects list for toBlockFlow. This can result in toBlockFlow containing |
| // floats that are not in it's floating objects list, but are in the |
| // floating objects lists of siblings and parents. This can cause problems |
| // when the float itself is deleted, since the deletion code assumes that |
| // if a float is not in it's containing block's floating objects list, it |
| // isn't in any floating objects list. In order to preserve this condition |
| // (removing it has serious performance implications), we need to copy the |
| // floating objects from the old block (this) to the new block (toBlockFlow). |
| // The float's metrics will likely all be wrong, but since toBlockFlow is |
| // already marked for layout, this will get fixed before anything gets |
| // displayed. |
| // See bug https://code.google.com/p/chromium/issues/detail?id=230907 |
| if (m_floatingObjects) { |
| if (!toBlockFlow->m_floatingObjects) |
| toBlockFlow->createFloatingObjects(); |
| |
| const FloatingObjectSet& fromFloatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = fromFloatingObjectSet.end(); |
| |
| for (FloatingObjectSetIterator it = fromFloatingObjectSet.begin(); it != end; ++it) { |
| const FloatingObject& floatingObject = *it->get(); |
| |
| // Don't insert the object again if it's already in the list |
| if (toBlockFlow->containsFloat(floatingObject.layoutObject())) |
| continue; |
| |
| toBlockFlow->m_floatingObjects->add(floatingObject.unsafeClone()); |
| } |
| } |
| |
| } |
| |
| void LayoutBlockFlow::invalidatePaintForOverhangingFloats(bool paintAllDescendants) |
| { |
| // Invalidate paint of any overhanging floats (if we know we're the one to paint them). |
| // Otherwise, bail out. |
| if (!hasOverhangingFloats()) |
| return; |
| |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) { |
| const FloatingObject& floatingObject = *it->get(); |
| // Only issue paint invaldiations for the object if it is overhanging, is not in its own layer, and |
| // is our responsibility to paint (m_shouldPaint is set). When paintAllDescendants is true, the latter |
| // condition is replaced with being a descendant of us. |
| if (logicalBottomForFloat(floatingObject) > logicalHeight() |
| && !floatingObject.layoutObject()->hasSelfPaintingLayer() |
| && (floatingObject.shouldPaint() || (paintAllDescendants && floatingObject.layoutObject()->isDescendantOf(this)))) { |
| |
| LayoutBox* floatingLayoutBox = floatingObject.layoutObject(); |
| floatingLayoutBox->setShouldDoFullPaintInvalidation(); |
| floatingLayoutBox->invalidatePaintForOverhangingFloats(false); |
| } |
| } |
| } |
| |
| void LayoutBlockFlow::invalidatePaintForOverflow() |
| { |
| // FIXME: We could tighten up the left and right invalidation points if we let layoutInlineChildren fill them in based off the particular lines |
| // it had to lay out. We wouldn't need the hasOverflowClip() hack in that case either. |
| LayoutUnit paintInvalidationLogicalLeft = logicalLeftVisualOverflow(); |
| LayoutUnit paintInvalidationLogicalRight = logicalRightVisualOverflow(); |
| if (hasOverflowClip()) { |
| // 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. |
| // 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. |
| // layoutInlineChildren should be patched to compute the entire paint invalidation rect. |
| paintInvalidationLogicalLeft = std::min(paintInvalidationLogicalLeft, logicalLeftLayoutOverflow()); |
| paintInvalidationLogicalRight = std::max(paintInvalidationLogicalRight, logicalRightLayoutOverflow()); |
| } |
| |
| LayoutRect paintInvalidationRect; |
| if (isHorizontalWritingMode()) |
| paintInvalidationRect = LayoutRect(paintInvalidationLogicalLeft, m_paintInvalidationLogicalTop, paintInvalidationLogicalRight - paintInvalidationLogicalLeft, m_paintInvalidationLogicalBottom - m_paintInvalidationLogicalTop); |
| else |
| paintInvalidationRect = LayoutRect(m_paintInvalidationLogicalTop, paintInvalidationLogicalLeft, m_paintInvalidationLogicalBottom - m_paintInvalidationLogicalTop, paintInvalidationLogicalRight - paintInvalidationLogicalLeft); |
| |
| if (hasOverflowClip()) { |
| // Adjust the paint invalidation rect for scroll offset |
| paintInvalidationRect.move(-scrolledContentOffset()); |
| |
| // Don't allow this rect to spill out of our overflow box. |
| paintInvalidationRect.intersect(LayoutRect(LayoutPoint(), size())); |
| } |
| |
| // Make sure the rect is still non-empty after intersecting for overflow above |
| if (!paintInvalidationRect.isEmpty()) { |
| // Hits in media/event-attributes.html |
| DisableCompositingQueryAsserts disabler; |
| |
| invalidatePaintRectangle(paintInvalidationRect); // We need to do a partial paint invalidation of our content. |
| if (hasReflection()) |
| invalidatePaintRectangle(reflectedRect(paintInvalidationRect)); |
| } |
| |
| m_paintInvalidationLogicalTop = 0; |
| m_paintInvalidationLogicalBottom = 0; |
| } |
| |
| void LayoutBlockFlow::paintFloats(const PaintInfo& paintInfo, const LayoutPoint& paintOffset, bool preservePhase) |
| { |
| BlockFlowPainter(*this).paintFloats(paintInfo, paintOffset, preservePhase); |
| } |
| |
| void LayoutBlockFlow::paintSelection(const PaintInfo& paintInfo, const LayoutPoint& paintOffset) |
| { |
| BlockFlowPainter(*this).paintSelection(paintInfo, paintOffset); |
| } |
| |
| void LayoutBlockFlow::clipOutFloatingObjects(const LayoutBlock* rootBlock, ClipScope& clipScope, |
| const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock) const |
| { |
| if (!m_floatingObjects) |
| return; |
| |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) { |
| const FloatingObject& floatingObject = *it->get(); |
| LayoutRect floatBox(LayoutPoint(offsetFromRootBlock), floatingObject.layoutObject()->size()); |
| floatBox.move(positionForFloatIncludingMargin(floatingObject)); |
| rootBlock->flipForWritingMode(floatBox); |
| floatBox.move(rootBlockPhysicalPosition.x(), rootBlockPhysicalPosition.y()); |
| |
| clipScope.clip(floatBox, SkRegion::kDifference_Op); |
| } |
| } |
| |
| void LayoutBlockFlow::clearFloats(EClear clear) |
| { |
| positionNewFloats(); |
| // set y position |
| LayoutUnit newY = 0; |
| switch (clear) { |
| case CLEFT: |
| newY = lowestFloatLogicalBottom(FloatingObject::FloatLeft); |
| break; |
| case CRIGHT: |
| newY = lowestFloatLogicalBottom(FloatingObject::FloatRight); |
| break; |
| case CBOTH: |
| newY = lowestFloatLogicalBottom(); |
| default: |
| break; |
| } |
| if (size().height() < newY) |
| setLogicalHeight(newY); |
| } |
| |
| bool LayoutBlockFlow::containsFloat(LayoutBox* layoutBox) const |
| { |
| return m_floatingObjects && m_floatingObjects->set().contains<FloatingObjectHashTranslator>(layoutBox); |
| } |
| |
| void LayoutBlockFlow::removeFloatingObjects() |
| { |
| if (!m_floatingObjects) |
| return; |
| |
| markSiblingsWithFloatsForLayout(); |
| |
| m_floatingObjects->clear(); |
| } |
| |
| LayoutPoint LayoutBlockFlow::flipFloatForWritingModeForChild(const FloatingObject& child, const LayoutPoint& point) const |
| { |
| if (!style()->isFlippedBlocksWritingMode()) |
| return point; |
| |
| // This is similar to LayoutBox::flipForWritingModeForChild. We have to subtract out our left/top offsets twice, since |
| // it's going to get added back in. We hide this complication here so that the calling code looks normal for the unflipped |
| // case. |
| if (isHorizontalWritingMode()) |
| return LayoutPoint(point.x(), point.y() + size().height() - child.layoutObject()->size().height() - 2 * yPositionForFloatIncludingMargin(child)); |
| return LayoutPoint(point.x() + size().width() - child.layoutObject()->size().width() - 2 * xPositionForFloatIncludingMargin(child), point.y()); |
| } |
| |
| LayoutUnit LayoutBlockFlow::logicalLeftOffsetForPositioningFloat(LayoutUnit logicalTop, LayoutUnit fixedOffset, bool applyTextIndent, LayoutUnit* heightRemaining) const |
| { |
| LayoutUnit offset = fixedOffset; |
| if (m_floatingObjects && m_floatingObjects->hasLeftObjects()) |
| offset = m_floatingObjects->logicalLeftOffsetForPositioningFloat(fixedOffset, logicalTop, heightRemaining); |
| return adjustLogicalLeftOffsetForLine(offset, applyTextIndent); |
| } |
| |
| LayoutUnit LayoutBlockFlow::logicalRightOffsetForPositioningFloat(LayoutUnit logicalTop, LayoutUnit fixedOffset, bool applyTextIndent, LayoutUnit* heightRemaining) const |
| { |
| LayoutUnit offset = fixedOffset; |
| if (m_floatingObjects && m_floatingObjects->hasRightObjects()) |
| offset = m_floatingObjects->logicalRightOffsetForPositioningFloat(fixedOffset, logicalTop, heightRemaining); |
| return adjustLogicalRightOffsetForLine(offset, applyTextIndent); |
| } |
| |
| LayoutUnit LayoutBlockFlow::adjustLogicalLeftOffsetForLine(LayoutUnit offsetFromFloats, bool applyTextIndent) const |
| { |
| LayoutUnit left = offsetFromFloats; |
| |
| if (applyTextIndent && style()->isLeftToRightDirection()) |
| left += textIndentOffset(); |
| |
| return left; |
| } |
| |
| LayoutUnit LayoutBlockFlow::adjustLogicalRightOffsetForLine(LayoutUnit offsetFromFloats, bool applyTextIndent) const |
| { |
| LayoutUnit right = offsetFromFloats; |
| |
| if (applyTextIndent && !style()->isLeftToRightDirection()) |
| right -= textIndentOffset(); |
| |
| return right; |
| } |
| |
| LayoutPoint LayoutBlockFlow::computeLogicalLocationForFloat(const FloatingObject& floatingObject, LayoutUnit logicalTopOffset) const |
| { |
| LayoutBox* childBox = floatingObject.layoutObject(); |
| LayoutUnit logicalLeftOffset = logicalLeftOffsetForContent(); // Constant part of left offset. |
| LayoutUnit logicalRightOffset; // Constant part of right offset. |
| logicalRightOffset = logicalRightOffsetForContent(); |
| |
| LayoutUnit floatLogicalWidth = std::min(logicalWidthForFloat(floatingObject), logicalRightOffset - logicalLeftOffset); // The width we look for. |
| |
| LayoutUnit floatLogicalLeft; |
| |
| bool insideFlowThread = flowThreadContainingBlock(); |
| |
| if (childBox->style()->floating() == LeftFloat) { |
| LayoutUnit heightRemainingLeft = 1; |
| LayoutUnit heightRemainingRight = 1; |
| floatLogicalLeft = logicalLeftOffsetForPositioningFloat(logicalTopOffset, logicalLeftOffset, false, &heightRemainingLeft); |
| while (logicalRightOffsetForPositioningFloat(logicalTopOffset, logicalRightOffset, false, &heightRemainingRight) - floatLogicalLeft < floatLogicalWidth) { |
| logicalTopOffset += std::min(heightRemainingLeft, heightRemainingRight); |
| floatLogicalLeft = logicalLeftOffsetForPositioningFloat(logicalTopOffset, logicalLeftOffset, false, &heightRemainingLeft); |
| if (insideFlowThread) { |
| // Have to re-evaluate all of our offsets, since they may have changed. |
| logicalRightOffset = logicalRightOffsetForContent(); // Constant part of right offset. |
| logicalLeftOffset = logicalLeftOffsetForContent(); // Constant part of left offset. |
| floatLogicalWidth = std::min(logicalWidthForFloat(floatingObject), logicalRightOffset - logicalLeftOffset); |
| } |
| } |
| floatLogicalLeft = std::max(logicalLeftOffset - borderAndPaddingLogicalLeft(), floatLogicalLeft); |
| } else { |
| LayoutUnit heightRemainingLeft = 1; |
| LayoutUnit heightRemainingRight = 1; |
| floatLogicalLeft = logicalRightOffsetForPositioningFloat(logicalTopOffset, logicalRightOffset, false, &heightRemainingRight); |
| while (floatLogicalLeft - logicalLeftOffsetForPositioningFloat(logicalTopOffset, logicalLeftOffset, false, &heightRemainingLeft) < floatLogicalWidth) { |
| logicalTopOffset += std::min(heightRemainingLeft, heightRemainingRight); |
| floatLogicalLeft = logicalRightOffsetForPositioningFloat(logicalTopOffset, logicalRightOffset, false, &heightRemainingRight); |
| if (insideFlowThread) { |
| // Have to re-evaluate all of our offsets, since they may have changed. |
| logicalRightOffset = logicalRightOffsetForContent(); // Constant part of right offset. |
| logicalLeftOffset = logicalLeftOffsetForContent(); // Constant part of left offset. |
| floatLogicalWidth = std::min(logicalWidthForFloat(floatingObject), logicalRightOffset - logicalLeftOffset); |
| } |
| } |
| // Use the original width of the float here, since the local variable |
| // |floatLogicalWidth| was capped to the available line width. See |
| // fast/block/float/clamped-right-float.html. |
| floatLogicalLeft -= logicalWidthForFloat(floatingObject); |
| } |
| |
| return LayoutPoint(floatLogicalLeft, logicalTopOffset); |
| } |
| |
| FloatingObject* LayoutBlockFlow::insertFloatingObject(LayoutBox& floatBox) |
| { |
| ASSERT(floatBox.isFloating()); |
| |
| // Create the list of special objects if we don't aleady have one |
| if (!m_floatingObjects) { |
| createFloatingObjects(); |
| } else { |
| // Don't insert the object again if it's already in the list |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator it = floatingObjectSet.find<FloatingObjectHashTranslator>(&floatBox); |
| if (it != floatingObjectSet.end()) |
| return it->get(); |
| } |
| |
| // Create the special object entry & append it to the list |
| |
| OwnPtr<FloatingObject> newObj = FloatingObject::create(&floatBox); |
| |
| // Our location is irrelevant if we're unsplittable or no pagination is in effect. |
| // Just go ahead and lay out the float. |
| bool isChildLayoutBlock = floatBox.isLayoutBlock(); |
| if (isChildLayoutBlock && !floatBox.needsLayout() && view()->layoutState()->pageLogicalHeightChanged()) |
| floatBox.setChildNeedsLayout(MarkOnlyThis); |
| |
| bool needsBlockDirectionLocationSetBeforeLayout = isChildLayoutBlock && view()->layoutState()->needsBlockDirectionLocationSetBeforeLayout(); |
| if (!needsBlockDirectionLocationSetBeforeLayout || isWritingModeRoot()) { // We are unsplittable if we're a block flow root. |
| floatBox.layoutIfNeeded(); |
| } else { |
| floatBox.updateLogicalWidth(); |
| floatBox.computeAndSetBlockDirectionMargins(this); |
| } |
| |
| setLogicalWidthForFloat(*newObj, logicalWidthForChild(floatBox) + marginStartForChild(floatBox) + marginEndForChild(floatBox)); |
| |
| return m_floatingObjects->add(newObj.release()); |
| } |
| |
| void LayoutBlockFlow::removeFloatingObject(LayoutBox* floatBox) |
| { |
| if (m_floatingObjects) { |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator it = floatingObjectSet.find<FloatingObjectHashTranslator>(floatBox); |
| if (it != floatingObjectSet.end()) { |
| FloatingObject& floatingObject = *it->get(); |
| if (childrenInline()) { |
| LayoutUnit logicalTop = logicalTopForFloat(floatingObject); |
| LayoutUnit logicalBottom = logicalBottomForFloat(floatingObject); |
| |
| // Fix for https://bugs.webkit.org/show_bug.cgi?id=54995. |
| if (logicalBottom < 0 || logicalBottom < logicalTop || logicalTop == LayoutUnit::max()) { |
| logicalBottom = LayoutUnit::max(); |
| } else { |
| // Special-case zero- and less-than-zero-height floats: those don't touch |
| // the line that they're on, but it still needs to be dirtied. This is |
| // accomplished by pretending they have a height of 1. |
| logicalBottom = std::max(logicalBottom, logicalTop + 1); |
| } |
| if (floatingObject.originatingLine()) { |
| if (!selfNeedsLayout()) { |
| ASSERT(floatingObject.originatingLine()->layoutObject() == this); |
| floatingObject.originatingLine()->markDirty(); |
| } |
| #if ENABLE(ASSERT) |
| floatingObject.setOriginatingLine(nullptr); |
| #endif |
| } |
| markLinesDirtyInBlockRange(0, logicalBottom); |
| } |
| m_floatingObjects->remove(&floatingObject); |
| } |
| } |
| } |
| |
| void LayoutBlockFlow::removeFloatingObjectsBelow(FloatingObject* lastFloat, int logicalOffset) |
| { |
| if (!containsFloats()) |
| return; |
| |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObject* curr = floatingObjectSet.last().get(); |
| while (curr != lastFloat && (!curr->isPlaced() || logicalTopForFloat(*curr) >= logicalOffset)) { |
| m_floatingObjects->remove(curr); |
| if (floatingObjectSet.isEmpty()) |
| break; |
| curr = floatingObjectSet.last().get(); |
| } |
| } |
| |
| bool LayoutBlockFlow::positionNewFloats(LineWidth* width) |
| { |
| if (!m_floatingObjects) |
| return false; |
| |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| if (floatingObjectSet.isEmpty()) |
| return false; |
| |
| // If all floats have already been positioned, then we have no work to do. |
| if (floatingObjectSet.last()->isPlaced()) |
| return false; |
| |
| // Move backwards through our floating object list until we find a float that has |
| // already been positioned. Then we'll be able to move forward, positioning all of |
| // the new floats that need it. |
| FloatingObjectSetIterator it = floatingObjectSet.end(); |
| --it; // Go to last item. |
| FloatingObjectSetIterator begin = floatingObjectSet.begin(); |
| FloatingObject* lastPlacedFloatingObject = nullptr; |
| while (it != begin) { |
| --it; |
| if ((*it)->isPlaced()) { |
| lastPlacedFloatingObject = it->get(); |
| ++it; |
| break; |
| } |
| } |
| |
| LayoutUnit logicalTop = logicalHeight(); |
| |
| // The float cannot start above the top position of the last positioned float. |
| if (lastPlacedFloatingObject) |
| logicalTop = std::max(logicalTopForFloat(*lastPlacedFloatingObject), logicalTop); |
| |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| // Now walk through the set of unpositioned floats and place them. |
| for (; it != end; ++it) { |
| FloatingObject& floatingObject = *it->get(); |
| // The containing block is responsible for positioning floats, so if we have floats in our |
| // list that come from somewhere else, do not attempt to position them. |
| if (floatingObject.layoutObject()->containingBlock() != this) |
| continue; |
| |
| LayoutBox* childBox = floatingObject.layoutObject(); |
| |
| // FIXME Investigate if this can be removed. crbug.com/370006 |
| childBox->setMayNeedPaintInvalidation(); |
| |
| LayoutUnit childLogicalLeftMargin = style()->isLeftToRightDirection() ? marginStartForChild(*childBox) : marginEndForChild(*childBox); |
| if (childBox->style()->clear() & CLEFT) |
| logicalTop = std::max(lowestFloatLogicalBottom(FloatingObject::FloatLeft), logicalTop); |
| if (childBox->style()->clear() & CRIGHT) |
| logicalTop = std::max(lowestFloatLogicalBottom(FloatingObject::FloatRight), logicalTop); |
| |
| LayoutPoint floatLogicalLocation = computeLogicalLocationForFloat(floatingObject, logicalTop); |
| |
| setLogicalLeftForFloat(floatingObject, floatLogicalLocation.x()); |
| |
| setLogicalLeftForChild(*childBox, floatLogicalLocation.x() + childLogicalLeftMargin); |
| setLogicalTopForChild(*childBox, floatLogicalLocation.y() + marginBeforeForChild(*childBox)); |
| |
| SubtreeLayoutScope layoutScope(*childBox); |
| LayoutState* layoutState = view()->layoutState(); |
| bool isPaginated = layoutState->isPaginated(); |
| if (isPaginated && !childBox->needsLayout()) |
| childBox->markForPaginationRelayoutIfNeeded(layoutScope); |
| |
| childBox->layoutIfNeeded(); |
| |
| if (isPaginated) { |
| // If we are unsplittable and don't fit, then we need to move down. |
| // We include our margins as part of the unsplittable area. |
| LayoutUnit newLogicalTop = adjustForUnsplittableChild(*childBox, floatLogicalLocation.y(), true); |
| |
| // See if we have a pagination strut that is making us move down further. |
| // Note that an unsplittable child can't also have a pagination strut, so this is |
| // exclusive with the case above. |
| LayoutBlockFlow* childBlockFlow = childBox->isLayoutBlockFlow() ? toLayoutBlockFlow(childBox) : 0; |
| if (childBlockFlow && childBlockFlow->paginationStrut()) { |
| newLogicalTop += childBlockFlow->paginationStrut(); |
| childBlockFlow->setPaginationStrut(0); |
| } |
| |
| if (newLogicalTop != floatLogicalLocation.y()) { |
| floatingObject.setPaginationStrut(newLogicalTop - floatLogicalLocation.y()); |
| |
| floatLogicalLocation = computeLogicalLocationForFloat(floatingObject, newLogicalTop); |
| setLogicalLeftForFloat(floatingObject, floatLogicalLocation.x()); |
| |
| setLogicalLeftForChild(*childBox, floatLogicalLocation.x() + childLogicalLeftMargin); |
| setLogicalTopForChild(*childBox, floatLogicalLocation.y() + marginBeforeForChild(*childBox)); |
| |
| if (childBox->isLayoutBlock()) |
| childBox->setChildNeedsLayout(MarkOnlyThis); |
| childBox->layoutIfNeeded(); |
| } |
| } |
| |
| setLogicalTopForFloat(floatingObject, floatLogicalLocation.y()); |
| |
| setLogicalHeightForFloat(floatingObject, logicalHeightForChild(*childBox) + marginBeforeForChild(*childBox) + marginAfterForChild(*childBox)); |
| |
| m_floatingObjects->addPlacedObject(floatingObject); |
| |
| if (ShapeOutsideInfo* shapeOutside = childBox->shapeOutsideInfo()) |
| shapeOutside->setReferenceBoxLogicalSize(logicalSizeForChild(*childBox)); |
| |
| if (width) |
| width->shrinkAvailableWidthForNewFloatIfNeeded(floatingObject); |
| } |
| return true; |
| } |
| |
| bool LayoutBlockFlow::hasOverhangingFloat(LayoutBox* layoutBox) |
| { |
| if (!m_floatingObjects || !parent()) |
| return false; |
| |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator it = floatingObjectSet.find<FloatingObjectHashTranslator>(layoutBox); |
| if (it == floatingObjectSet.end()) |
| return false; |
| |
| return logicalBottomForFloat(*it->get()) > logicalHeight(); |
| } |
| |
| void LayoutBlockFlow::addIntrudingFloats(LayoutBlockFlow* prev, LayoutUnit logicalLeftOffset, LayoutUnit logicalTopOffset) |
| { |
| ASSERT(!avoidsFloats()); |
| |
| // If we create our own block formatting context then our contents don't interact with floats outside it, even those from our parent. |
| if (createsNewFormattingContext()) |
| return; |
| |
| // If the parent or previous sibling doesn't have any floats to add, don't bother. |
| if (!prev->m_floatingObjects) |
| return; |
| |
| logicalLeftOffset += marginLogicalLeft(); |
| |
| const FloatingObjectSet& prevSet = prev->m_floatingObjects->set(); |
| FloatingObjectSetIterator prevEnd = prevSet.end(); |
| for (FloatingObjectSetIterator prevIt = prevSet.begin(); prevIt != prevEnd; ++prevIt) { |
| FloatingObject& floatingObject = *prevIt->get(); |
| if (logicalBottomForFloat(floatingObject) > logicalTopOffset) { |
| if (!m_floatingObjects || !m_floatingObjects->set().contains(&floatingObject)) { |
| // We create the floating object list lazily. |
| if (!m_floatingObjects) |
| createFloatingObjects(); |
| |
| // Applying the child's margin makes no sense in the case where the child was passed in. |
| // since this margin was added already through the modification of the |logicalLeftOffset| variable |
| // above. |logicalLeftOffset| will equal the margin in this case, so it's already been taken |
| // into account. Only apply this code if prev is the parent, since otherwise the left margin |
| // will get applied twice. |
| LayoutSize offset = isHorizontalWritingMode() |
| ? LayoutSize(logicalLeftOffset - (prev != parent() ? prev->marginLeft() : LayoutUnit()), logicalTopOffset) |
| : LayoutSize(logicalTopOffset, logicalLeftOffset - (prev != parent() ? prev->marginTop() : LayoutUnit())); |
| |
| m_floatingObjects->add(floatingObject.copyToNewContainer(offset)); |
| } |
| } |
| } |
| } |
| |
| void LayoutBlockFlow::addOverhangingFloats(LayoutBlockFlow* child, bool makeChildPaintOtherFloats) |
| { |
| // Prevent floats from being added to the canvas by the root element, e.g., <html>. |
| if (!child->containsFloats() || child->createsNewFormattingContext()) |
| return; |
| |
| LayoutUnit childLogicalTop = child->logicalTop(); |
| LayoutUnit childLogicalLeft = child->logicalLeft(); |
| |
| // Floats that will remain the child's responsibility to paint should factor into its |
| // overflow. |
| FloatingObjectSetIterator childEnd = child->m_floatingObjects->set().end(); |
| for (FloatingObjectSetIterator childIt = child->m_floatingObjects->set().begin(); childIt != childEnd; ++childIt) { |
| FloatingObject& floatingObject = *childIt->get(); |
| LayoutUnit logicalBottomForFloat = std::min(this->logicalBottomForFloat(floatingObject), LayoutUnit::max() - childLogicalTop); |
| LayoutUnit logicalBottom = childLogicalTop + logicalBottomForFloat; |
| |
| if (logicalBottom > logicalHeight()) { |
| // If the object is not in the list, we add it now. |
| if (!containsFloat(floatingObject.layoutObject())) { |
| LayoutSize offset = isHorizontalWritingMode() ? LayoutSize(-childLogicalLeft, -childLogicalTop) : LayoutSize(-childLogicalTop, -childLogicalLeft); |
| bool shouldPaint = false; |
| |
| // The nearest enclosing layer always paints the float (so that zindex and stacking |
| // behaves properly). We always want to propagate the desire to paint the float as |
| // far out as we can, to the outermost block that overlaps the float, stopping only |
| // if we hit a self-painting layer boundary. |
| if (floatingObject.layoutObject()->enclosingFloatPaintingLayer() == enclosingFloatPaintingLayer() && !floatingObject.isLowestNonOverhangingFloatInChild()) { |
| floatingObject.setShouldPaint(false); |
| shouldPaint = true; |
| } |
| // We create the floating object list lazily. |
| if (!m_floatingObjects) |
| createFloatingObjects(); |
| |
| m_floatingObjects->add(floatingObject.copyToNewContainer(offset, shouldPaint, true)); |
| } |
| } else { |
| if (makeChildPaintOtherFloats && !floatingObject.shouldPaint() && !floatingObject.layoutObject()->hasSelfPaintingLayer() && !floatingObject.isLowestNonOverhangingFloatInChild() |
| && floatingObject.layoutObject()->isDescendantOf(child) && floatingObject.layoutObject()->enclosingFloatPaintingLayer() == child->enclosingFloatPaintingLayer()) { |
| // The float is not overhanging from this block, so if it is a descendant of the child, the child should |
| // paint it (the other case is that it is intruding into the child), unless it has its own layer or enclosing |
| // layer. |
| // If makeChildPaintOtherFloats is false, it means that the child must already know about all the floats |
| // it should paint. |
| floatingObject.setShouldPaint(true); |
| } |
| |
| // 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 |
| // child now. |
| if (floatingObject.isDescendant()) |
| child->addOverflowFromChild(floatingObject.layoutObject(), LayoutSize(xPositionForFloatIncludingMargin(floatingObject), yPositionForFloatIncludingMargin(floatingObject))); |
| } |
| } |
| } |
| |
| LayoutUnit LayoutBlockFlow::lowestFloatLogicalBottom(FloatingObject::Type floatType) const |
| { |
| if (!m_floatingObjects) |
| return LayoutUnit(); |
| |
| return m_floatingObjects->lowestFloatLogicalBottom(floatType); |
| } |
| |
| LayoutUnit LayoutBlockFlow::nextFloatLogicalBottomBelow(LayoutUnit logicalHeight, ShapeOutsideFloatOffsetMode offsetMode) const |
| { |
| if (!m_floatingObjects) |
| return logicalHeight; |
| |
| LayoutUnit logicalBottom; |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) { |
| const FloatingObject& floatingObject = *it->get(); |
| LayoutUnit floatLogicalBottom = logicalBottomForFloat(floatingObject); |
| ShapeOutsideInfo* shapeOutside = floatingObject.layoutObject()->shapeOutsideInfo(); |
| if (shapeOutside && (offsetMode == ShapeOutsideFloatShapeOffset)) { |
| LayoutUnit shapeLogicalBottom = logicalTopForFloat(floatingObject) + marginBeforeForChild(*floatingObject.layoutObject()) + shapeOutside->shapeLogicalBottom(); |
| // Use the shapeLogicalBottom unless it extends outside of the margin box, in which case it is clipped. |
| if (shapeLogicalBottom < floatLogicalBottom) |
| floatLogicalBottom = shapeLogicalBottom; |
| } |
| if (floatLogicalBottom > logicalHeight) |
| logicalBottom = logicalBottom ? std::min(floatLogicalBottom, logicalBottom) : floatLogicalBottom; |
| } |
| |
| return logicalBottom; |
| } |
| |
| bool LayoutBlockFlow::hitTestFloats(HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset) |
| { |
| if (!m_floatingObjects) |
| return false; |
| |
| LayoutPoint adjustedLocation = accumulatedOffset; |
| if (isLayoutView()) { |
| DoublePoint position = toLayoutView(this)->frameView()->scrollPositionDouble(); |
| adjustedLocation.move(position.x(), position.y()); |
| } |
| |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator begin = floatingObjectSet.begin(); |
| for (FloatingObjectSetIterator it = floatingObjectSet.end(); it != begin;) { |
| --it; |
| const FloatingObject& floatingObject = *it->get(); |
| if (floatingObject.shouldPaint() && !floatingObject.layoutObject()->hasSelfPaintingLayer()) { |
| LayoutUnit xOffset = xPositionForFloatIncludingMargin(floatingObject) - floatingObject.layoutObject()->location().x(); |
| LayoutUnit yOffset = yPositionForFloatIncludingMargin(floatingObject) - floatingObject.layoutObject()->location().y(); |
| LayoutPoint childPoint = flipFloatForWritingModeForChild(floatingObject, adjustedLocation + LayoutSize(xOffset, yOffset)); |
| if (floatingObject.layoutObject()->hitTest(result, locationInContainer, childPoint)) { |
| updateHitTestResult(result, locationInContainer.point() - toLayoutSize(childPoint)); |
| return true; |
| } |
| } |
| } |
| |
| return false; |
| } |
| |
| LayoutUnit LayoutBlockFlow::logicalLeftFloatOffsetForLine(LayoutUnit logicalTop, LayoutUnit fixedOffset, LayoutUnit logicalHeight) const |
| { |
| if (m_floatingObjects && m_floatingObjects->hasLeftObjects()) |
| return m_floatingObjects->logicalLeftOffset(fixedOffset, logicalTop, logicalHeight); |
| |
| return fixedOffset; |
| } |
| |
| LayoutUnit LayoutBlockFlow::logicalRightFloatOffsetForLine(LayoutUnit logicalTop, LayoutUnit fixedOffset, LayoutUnit logicalHeight) const |
| { |
| if (m_floatingObjects && m_floatingObjects->hasRightObjects()) |
| return m_floatingObjects->logicalRightOffset(fixedOffset, logicalTop, logicalHeight); |
| |
| return fixedOffset; |
| } |
| |
| LayoutRect LayoutBlockFlow::selectionRectForPaintInvalidation(const LayoutBoxModelObject* paintInvalidationContainer) const |
| { |
| LayoutRect rect = selectionGapRectsForPaintInvalidation(paintInvalidationContainer); |
| // FIXME: groupedMapping() leaks the squashing abstraction. |
| if (paintInvalidationContainer->layer()->groupedMapping()) |
| DeprecatedPaintLayer::mapRectToPaintBackingCoordinates(paintInvalidationContainer, rect); |
| return rect; |
| } |
| |
| GapRects LayoutBlockFlow::selectionGapRectsForPaintInvalidation(const LayoutBoxModelObject* paintInvalidationContainer) const |
| { |
| ASSERT(!needsLayout()); |
| |
| if (!shouldPaintSelectionGaps()) |
| return GapRects(); |
| |
| TransformState transformState(TransformState::ApplyTransformDirection, FloatPoint()); |
| mapLocalToContainer(paintInvalidationContainer, transformState, ApplyContainerFlip | UseTransforms); |
| LayoutPoint offsetFromPaintInvalidationContainer = roundedLayoutPoint(transformState.mappedPoint()); |
| |
| if (hasOverflowClip()) |
| offsetFromPaintInvalidationContainer -= scrolledContentOffset(); |
| |
| LayoutUnit lastTop = 0; |
| LayoutUnit lastLeft = logicalLeftSelectionOffset(this, lastTop); |
| LayoutUnit lastRight = logicalRightSelectionOffset(this, lastTop); |
| |
| return selectionGaps(this, offsetFromPaintInvalidationContainer, LayoutSize(), lastTop, lastLeft, lastRight); |
| } |
| |
| static void clipOutPositionedObjects(ClipScope& clipScope, const LayoutPoint& offset, TrackedLayoutBoxListHashSet* positionedObjects) |
| { |
| if (!positionedObjects) |
| return; |
| |
| TrackedLayoutBoxListHashSet::const_iterator end = positionedObjects->end(); |
| for (TrackedLayoutBoxListHashSet::const_iterator it = positionedObjects->begin(); it != end; ++it) { |
| LayoutBox* r = *it; |
| clipScope.clip(LayoutRect(flooredIntPoint(r->location() + offset), flooredIntSize(r->size())), SkRegion::kDifference_Op); |
| } |
| } |
| |
| GapRects LayoutBlockFlow::selectionGaps(const LayoutBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, |
| const LayoutSize& offsetFromRootBlock, LayoutUnit& lastLogicalTop, LayoutUnit& lastLogicalLeft, LayoutUnit& lastLogicalRight, |
| const PaintInfo* paintInfo, ClipScope* clipScope) const |
| { |
| // IMPORTANT: Callers of this method that intend for painting to happen need to do a save/restore. |
| if (clipScope) { |
| // Note that we don't clip out overflow for positioned objects. We just stick to the border box. |
| LayoutRect flippedBlockRect(LayoutPoint(offsetFromRootBlock), size()); |
| rootBlock->flipForWritingMode(flippedBlockRect); |
| flippedBlockRect.moveBy(rootBlockPhysicalPosition); |
| clipOutPositionedObjects(*clipScope, flippedBlockRect.location(), positionedObjects()); |
| if (isBody() || isDocumentElement()) // The <body> must make sure to examine its containingBlock's positioned objects. |
| for (LayoutBlock* cb = containingBlock(); cb && !cb->isLayoutView(); cb = cb->containingBlock()) |
| clipOutPositionedObjects(*clipScope, cb->location(), cb->positionedObjects()); // FIXME: Not right for flipped writing modes. |
| clipOutFloatingObjects(rootBlock, *clipScope, rootBlockPhysicalPosition, offsetFromRootBlock); |
| } |
| |
| GapRects result; |
| |
| if (hasTransformRelatedProperty() || style()->columnSpan()) |
| return result; |
| |
| if (childrenInline()) |
| result = inlineSelectionGaps(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, lastLogicalTop, lastLogicalLeft, lastLogicalRight, paintInfo); |
| else |
| result = blockSelectionGaps(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, lastLogicalTop, lastLogicalLeft, lastLogicalRight, paintInfo); |
| |
| // Go ahead and fill the vertical gap all the way to the bottom of our block if the selection extends past our block. |
| if (rootBlock == this && (selectionState() != SelectionBoth && selectionState() != SelectionEnd)) { |
| result.uniteCenter(blockSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, |
| lastLogicalTop, lastLogicalLeft, lastLogicalRight, logicalHeight(), paintInfo)); |
| } |
| return result; |
| } |
| |
| |
| GapRects LayoutBlockFlow::inlineSelectionGaps(const LayoutBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock, |
| LayoutUnit& lastLogicalTop, LayoutUnit& lastLogicalLeft, LayoutUnit& lastLogicalRight, const PaintInfo* paintInfo) const |
| { |
| GapRects result; |
| |
| bool containsStart = selectionState() == SelectionStart || selectionState() == SelectionBoth; |
| |
| if (!firstLineBox()) { |
| if (containsStart) { |
| // Go ahead and update our lastLogicalTop to be the bottom of the block. <hr>s or empty blocks with height can trip this |
| // case. |
| lastLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + logicalHeight(); |
| lastLogicalLeft = logicalLeftSelectionOffset(rootBlock, logicalHeight()); |
| lastLogicalRight = logicalRightSelectionOffset(rootBlock, logicalHeight()); |
| } |
| return result; |
| } |
| |
| RootInlineBox* lastSelectedLine = nullptr; |
| RootInlineBox* curr; |
| for (curr = firstRootBox(); curr && !curr->hasSelectedChildren(); curr = curr->nextRootBox()) { } |
| |
| // Now paint the gaps for the lines. |
| for (; curr && curr->hasSelectedChildren(); curr = curr->nextRootBox()) { |
| LayoutUnit selTop = curr->selectionTopAdjustedForPrecedingBlock(); |
| LayoutUnit selHeight = curr->selectionHeightAdjustedForPrecedingBlock(); |
| |
| if (!containsStart && !lastSelectedLine && selectionState() != SelectionStart && selectionState() != SelectionBoth) { |
| result.uniteCenter(blockSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, lastLogicalTop, |
| lastLogicalLeft, lastLogicalRight, selTop, paintInfo)); |
| } |
| |
| LayoutRect logicalRect(curr->logicalLeft(), selTop, curr->logicalWidth(), selTop + selHeight); |
| logicalRect.move(isHorizontalWritingMode() ? offsetFromRootBlock : offsetFromRootBlock.transposedSize()); |
| LayoutRect physicalRect = rootBlock->logicalRectToPhysicalRect(rootBlockPhysicalPosition, logicalRect); |
| if (!paintInfo || (isHorizontalWritingMode() && physicalRect.y() < paintInfo->rect.maxY() && physicalRect.maxY() > paintInfo->rect.y()) |
| || (!isHorizontalWritingMode() && physicalRect.x() < paintInfo->rect.maxX() && physicalRect.maxX() > paintInfo->rect.x())) |
| result.unite(curr->lineSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, selTop, selHeight, paintInfo)); |
| |
| lastSelectedLine = curr; |
| } |
| |
| if (containsStart && !lastSelectedLine) { |
| // VisibleSelection must start just after our last line. |
| lastSelectedLine = lastRootBox(); |
| } |
| |
| if (lastSelectedLine && selectionState() != SelectionEnd && selectionState() != SelectionBoth) { |
| // Go ahead and update our lastY to be the bottom of the last selected line. |
| lastLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + lastSelectedLine->selectionBottom(); |
| lastLogicalLeft = logicalLeftSelectionOffset(rootBlock, lastSelectedLine->selectionBottom()); |
| lastLogicalRight = logicalRightSelectionOffset(rootBlock, lastSelectedLine->selectionBottom()); |
| } |
| return result; |
| } |
| |
| IntRect alignSelectionRectToDevicePixels(LayoutRect& rect) |
| { |
| LayoutUnit roundedX = rect.x().round(); |
| return IntRect(roundedX, rect.y().round(), |
| (rect.maxX() - roundedX).round(), |
| snapSizeToPixel(rect.height(), rect.y())); |
| } |
| |
| bool LayoutBlockFlow::shouldPaintSelectionGaps() const |
| { |
| return selectionState() != SelectionNone && style()->visibility() == VISIBLE && isSelectionRoot(); |
| } |
| |
| LayoutRect LayoutBlockFlow::blockSelectionGap(const LayoutBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock, |
| LayoutUnit lastLogicalTop, LayoutUnit lastLogicalLeft, LayoutUnit lastLogicalRight, LayoutUnit logicalBottom, const PaintInfo* paintInfo) const |
| { |
| LayoutUnit logicalTop = lastLogicalTop; |
| LayoutUnit logicalHeight = rootBlock->blockDirectionOffset(offsetFromRootBlock) + logicalBottom - logicalTop; |
| if (logicalHeight <= 0) |
| return LayoutRect(); |
| |
| // Get the selection offsets for the bottom of the gap |
| LayoutUnit logicalLeft = std::max(lastLogicalLeft, logicalLeftSelectionOffset(rootBlock, logicalBottom)); |
| LayoutUnit logicalRight = std::min(lastLogicalRight, logicalRightSelectionOffset(rootBlock, logicalBottom)); |
| LayoutUnit logicalWidth = logicalRight - logicalLeft; |
| if (logicalWidth <= 0) |
| return LayoutRect(); |
| |
| LayoutRect gapRect = rootBlock->logicalRectToPhysicalRect(rootBlockPhysicalPosition, LayoutRect(logicalLeft, logicalTop, logicalWidth, logicalHeight)); |
| if (paintInfo) { |
| IntRect selectionGapRect = alignSelectionRectToDevicePixels(gapRect); |
| paintInfo->context->fillRect(selectionGapRect, selectionBackgroundColor()); |
| } |
| return gapRect; |
| } |
| |
| GapRects LayoutBlockFlow::blockSelectionGaps(const LayoutBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock, |
| LayoutUnit& lastLogicalTop, LayoutUnit& lastLogicalLeft, LayoutUnit& lastLogicalRight, const PaintInfo* paintInfo) const |
| { |
| GapRects result; |
| |
| // Go ahead and jump right to the first block child that contains some selected objects. |
| LayoutBox* curr; |
| for (curr = firstChildBox(); curr && curr->selectionState() == SelectionNone; curr = curr->nextSiblingBox()) { } |
| |
| for (bool sawSelectionEnd = false; curr && !sawSelectionEnd; curr = curr->nextSiblingBox()) { |
| SelectionState childState = curr->selectionState(); |
| if (childState == SelectionBoth || childState == SelectionEnd) |
| sawSelectionEnd = true; |
| |
| if (curr->isFloatingOrOutOfFlowPositioned()) |
| continue; // We must be a normal flow object in order to even be considered. |
| |
| if (curr->isRelPositioned() && curr->hasLayer()) { |
| // If the relposition offset is anything other than 0, then treat this just like an absolute positioned element. |
| // Just disregard it completely. |
| LayoutSize relOffset = curr->layer()->offsetForInFlowPosition(); |
| if (relOffset.width() || relOffset.height()) |
| continue; |
| } |
| |
| bool paintsOwnSelection = curr->shouldPaintSelectionGaps() || curr->isTable(); // FIXME: Eventually we won't special-case table like this. |
| bool fillBlockGaps = paintsOwnSelection || (curr->canBeSelectionLeaf() && childState != SelectionNone); |
| if (fillBlockGaps) { |
| // We need to fill the vertical gap above this object. |
| if (childState == SelectionEnd || childState == SelectionInside) { |
| // Fill the gap above the object. |
| result.uniteCenter(blockSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, lastLogicalTop, lastLogicalLeft, lastLogicalRight, |
| curr->logicalTop(), paintInfo)); |
| } |
| |
| // Only fill side gaps for objects that paint their own selection if we know for sure the selection is going to extend all the way *past* |
| // our object. We know this if the selection did not end inside our object. |
| if (paintsOwnSelection && (childState == SelectionStart || sawSelectionEnd)) |
| childState = SelectionNone; |
| |
| // Fill side gaps on this object based off its state. |
| bool leftGap, rightGap; |
| getSelectionGapInfo(childState, leftGap, rightGap); |
| |
| if (leftGap) |
| result.uniteLeft(logicalLeftSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, this, curr->logicalLeft(), curr->logicalTop(), curr->logicalHeight(), paintInfo)); |
| if (rightGap) |
| result.uniteRight(logicalRightSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, this, curr->logicalRight(), curr->logicalTop(), curr->logicalHeight(), paintInfo)); |
| |
| // Update lastLogicalTop to be just underneath the object. lastLogicalLeft and lastLogicalRight extend as far as |
| // they can without bumping into floating or positioned objects. Ideally they will go right up |
| // to the border of the root selection block. |
| lastLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + curr->logicalBottom(); |
| lastLogicalLeft = logicalLeftSelectionOffset(rootBlock, curr->logicalBottom()); |
| lastLogicalRight = logicalRightSelectionOffset(rootBlock, curr->logicalBottom()); |
| } else if (childState != SelectionNone && curr->isLayoutBlockFlow()) { |
| // We must be a block that has some selected object inside it. Go ahead and recur. |
| result.unite(toLayoutBlockFlow(curr)->selectionGaps(rootBlock, rootBlockPhysicalPosition, LayoutSize(offsetFromRootBlock.width() + curr->location().x(), offsetFromRootBlock.height() + curr->location().y()), |
| lastLogicalTop, lastLogicalLeft, lastLogicalRight, paintInfo)); |
| } |
| } |
| return result; |
| } |
| |
| LayoutRect LayoutBlockFlow::logicalLeftSelectionGap(const LayoutBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock, |
| const LayoutObject* selObj, LayoutUnit logicalLeft, LayoutUnit logicalTop, LayoutUnit logicalHeight, const PaintInfo* paintInfo) const |
| { |
| LayoutUnit rootBlockLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + logicalTop; |
| LayoutUnit rootBlockLogicalLeft = std::max(logicalLeftSelectionOffset(rootBlock, logicalTop), logicalLeftSelectionOffset(rootBlock, logicalTop + logicalHeight)); |
| LayoutUnit rootBlockLogicalRight = std::min(rootBlock->inlineDirectionOffset(offsetFromRootBlock) + logicalLeft, std::min(logicalRightSelectionOffset(rootBlock, logicalTop), logicalRightSelectionOffset(rootBlock, logicalTop + logicalHeight))); |
| LayoutUnit rootBlockLogicalWidth = rootBlockLogicalRight - rootBlockLogicalLeft; |
| if (rootBlockLogicalWidth <= 0) |
| return LayoutRect(); |
| |
| LayoutRect gapRect = rootBlock->logicalRectToPhysicalRect(rootBlockPhysicalPosition, LayoutRect(rootBlockLogicalLeft, rootBlockLogicalTop, rootBlockLogicalWidth, logicalHeight)); |
| if (paintInfo) { |
| IntRect selectionGapRect = alignSelectionRectToDevicePixels(gapRect); |
| paintInfo->context->fillRect(selectionGapRect, selObj->selectionBackgroundColor()); |
| } |
| return gapRect; |
| } |
| |
| LayoutRect LayoutBlockFlow::logicalRightSelectionGap(const LayoutBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock, |
| const LayoutObject* selObj, LayoutUnit logicalRight, LayoutUnit logicalTop, LayoutUnit logicalHeight, const PaintInfo* paintInfo) const |
| { |
| LayoutUnit rootBlockLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + logicalTop; |
| LayoutUnit rootBlockLogicalLeft = std::max(rootBlock->inlineDirectionOffset(offsetFromRootBlock) + logicalRight, max(logicalLeftSelectionOffset(rootBlock, logicalTop), logicalLeftSelectionOffset(rootBlock, logicalTop + logicalHeight))); |
| LayoutUnit rootBlockLogicalRight = std::min(logicalRightSelectionOffset(rootBlock, logicalTop), logicalRightSelectionOffset(rootBlock, logicalTop + logicalHeight)); |
| LayoutUnit rootBlockLogicalWidth = rootBlockLogicalRight - rootBlockLogicalLeft; |
| if (rootBlockLogicalWidth <= 0) |
| return LayoutRect(); |
| |
| LayoutRect gapRect = rootBlock->logicalRectToPhysicalRect(rootBlockPhysicalPosition, LayoutRect(rootBlockLogicalLeft, rootBlockLogicalTop, rootBlockLogicalWidth, logicalHeight)); |
| if (paintInfo) { |
| IntRect selectionGapRect = alignSelectionRectToDevicePixels(gapRect); |
| paintInfo->context->fillRect(selectionGapRect, selObj->selectionBackgroundColor()); |
| } |
| return gapRect; |
| } |
| |
| void LayoutBlockFlow::getSelectionGapInfo(SelectionState state, bool& leftGap, bool& rightGap) const |
| { |
| bool ltr = style()->isLeftToRightDirection(); |
| leftGap = (state == LayoutObject::SelectionInside) |
| || (state == LayoutObject::SelectionEnd && ltr) |
| || (state == LayoutObject::SelectionStart && !ltr); |
| rightGap = (state == LayoutObject::SelectionInside) |
| || (state == LayoutObject::SelectionStart && ltr) |
| || (state == LayoutObject::SelectionEnd && !ltr); |
| } |
| |
| void LayoutBlockFlow::setPaginationStrut(LayoutUnit strut) |
| { |
| if (!m_rareData) { |
| if (!strut) |
| return; |
| m_rareData = adoptPtr(new LayoutBlockFlowRareData(this)); |
| } |
| m_rareData->m_paginationStrut = strut; |
| } |
| |
| void LayoutBlockFlow::positionSpannerDescendant(LayoutMultiColumnSpannerPlaceholder& child) |
| { |
| LayoutBox& spanner = *child.layoutObjectInFlowThread(); |
| // FIXME: |spanner| is a descendant, but never a direct child, so the names here are bad, if |
| // nothing else. |
| setLogicalTopForChild(spanner, child.logicalTop()); |
| determineLogicalLeftPositionForChild(spanner); |
| } |
| |
| bool LayoutBlockFlow::avoidsFloats() const |
| { |
| // Floats can't intrude into our box if we have a non-auto column count or width. |
| // Note: we need to use LayoutBox::avoidsFloats here since LayoutBlock::avoidsFloats is always true. |
| return LayoutBox::avoidsFloats() || !style()->hasAutoColumnCount() || !style()->hasAutoColumnWidth(); |
| } |
| |
| void LayoutBlockFlow::moveChildrenTo(LayoutBoxModelObject* toBoxModelObject, LayoutObject* startChild, LayoutObject* endChild, LayoutObject* beforeChild, bool fullRemoveInsert) |
| { |
| if (childrenInline()) |
| deleteLineBoxTree(); |
| LayoutBoxModelObject::moveChildrenTo(toBoxModelObject, startChild, endChild, beforeChild, fullRemoveInsert); |
| } |
| |
| LayoutUnit LayoutBlockFlow::logicalLeftSelectionOffset(const LayoutBlock* rootBlock, LayoutUnit position) const |
| { |
| LayoutUnit logicalLeft = logicalLeftOffsetForLine(position, false); |
| if (logicalLeft == logicalLeftOffsetForContent()) |
| return LayoutBlock::logicalLeftSelectionOffset(rootBlock, position); |
| |
| const LayoutBlock* cb = this; |
| while (cb != rootBlock) { |
| logicalLeft += cb->logicalLeft(); |
| cb = cb->containingBlock(); |
| } |
| return logicalLeft; |
| } |
| |
| LayoutUnit LayoutBlockFlow::logicalRightSelectionOffset(const LayoutBlock* rootBlock, LayoutUnit position) const |
| { |
| LayoutUnit logicalRight = logicalRightOffsetForLine(position, false); |
| if (logicalRight == logicalRightOffsetForContent()) |
| return LayoutBlock::logicalRightSelectionOffset(rootBlock, position); |
| |
| const LayoutBlock* cb = this; |
| while (cb != rootBlock) { |
| logicalRight += cb->logicalLeft(); |
| cb = cb->containingBlock(); |
| } |
| return logicalRight; |
| } |
| |
| RootInlineBox* LayoutBlockFlow::createRootInlineBox() |
| { |
| return new RootInlineBox(*this); |
| } |
| |
| bool LayoutBlockFlow::isPagedOverflow(const ComputedStyle& style) |
| { |
| return style.isOverflowPaged() && node() != document().viewportDefiningElement(); |
| } |
| |
| LayoutBlockFlow::FlowThreadType LayoutBlockFlow::flowThreadType(const ComputedStyle& style) |
| { |
| if (isPagedOverflow(style)) |
| return PagedFlowThread; |
| if (style.specifiesColumns()) |
| return MultiColumnFlowThread; |
| return NoFlowThread; |
| } |
| |
| LayoutMultiColumnFlowThread* LayoutBlockFlow::createMultiColumnFlowThread(FlowThreadType type) |
| { |
| switch (type) { |
| case MultiColumnFlowThread: |
| return LayoutMultiColumnFlowThread::createAnonymous(document(), styleRef()); |
| case PagedFlowThread: |
| // Paged overflow is currently done using the multicol implementation. |
| return LayoutPagedFlowThread::createAnonymous(document(), styleRef()); |
| default: |
| ASSERT_NOT_REACHED(); |
| return nullptr; |
| } |
| } |
| |
| void LayoutBlockFlow::createOrDestroyMultiColumnFlowThreadIfNeeded(const ComputedStyle* oldStyle) |
| { |
| // Paged overflow trumps multicol in this implementation. Ideally, it should be possible to have |
| // both paged overflow and multicol on the same element, but then we need two flow |
| // threads. Anyway, this is nothing to worry about until we can actually nest multicol properly |
| // inside other fragmentation contexts. |
| FlowThreadType type = flowThreadType(styleRef()); |
| |
| if (multiColumnFlowThread()) { |
| ASSERT(oldStyle); |
| if (type != flowThreadType(*oldStyle)) { |
| // If we're no longer to be multicol/paged, destroy the flow thread. Also destroy it |
| // when switching between multicol and paged, since that affects the column set |
| // structure (multicol containers may have spanners, paged containers may not). |
| multiColumnFlowThread()->evacuateAndDestroy(); |
| ASSERT(!multiColumnFlowThread()); |
| } |
| } |
| |
| if (type == NoFlowThread || multiColumnFlowThread()) |
| return; |
| |
| // Ruby elements manage child insertion in a special way, and would mess up insertion of the |
| // flow thread. The flow thread needs to be a direct child of the multicol block (|this|). |
| if (isRuby()) |
| return; |
| |
| // Fieldsets look for a legend special child (layoutSpecialExcludedChild()). We currently only |
| // support one special child per layout object, and the flow thread would make for a second one. |
| if (isFieldset()) |
| return; |
| |
| // Form controls are replaced content, and are therefore not supposed to support multicol. |
| if (isFileUploadControl() || isTextControl() || isListBox()) |
| return; |
| |
| LayoutMultiColumnFlowThread* flowThread = createMultiColumnFlowThread(type); |
| addChild(flowThread); |
| |
| // Check that addChild() put the flow thread as a direct child, and didn't do fancy things. |
| ASSERT(flowThread->parent() == this); |
| |
| flowThread->populate(); |
| LayoutBlockFlowRareData& rareData = ensureRareData(); |
| ASSERT(!rareData.m_multiColumnFlowThread); |
| rareData.m_multiColumnFlowThread = flowThread; |
| } |
| |
| LayoutBlockFlow::LayoutBlockFlowRareData& LayoutBlockFlow::ensureRareData() |
| { |
| if (m_rareData) |
| return *m_rareData; |
| |
| m_rareData = adoptPtr(new LayoutBlockFlowRareData(this)); |
| return *m_rareData; |
| } |
| |
| void LayoutBlockFlow::positionDialog() |
| { |
| HTMLDialogElement* dialog = toHTMLDialogElement(node()); |
| if (dialog->centeringMode() == HTMLDialogElement::NotCentered) |
| return; |
| |
| bool canCenterDialog = (style()->position() == AbsolutePosition || style()->position() == FixedPosition) |
| && style()->hasAutoTopAndBottom(); |
| |
| if (dialog->centeringMode() == HTMLDialogElement::Centered) { |
| if (canCenterDialog) |
| setY(dialog->centeredPosition()); |
| return; |
| } |
| |
| ASSERT(dialog->centeringMode() == HTMLDialogElement::NeedsCentering); |
| if (!canCenterDialog) { |
| dialog->setNotCentered(); |
| return; |
| } |
| |
| FrameView* frameView = document().view(); |
| LayoutUnit top = (style()->position() == FixedPosition) ? 0 : frameView->scrollOffset().height(); |
| int visibleHeight = frameView->visibleContentRect(IncludeScrollbars).height(); |
| if (size().height() < visibleHeight) |
| top += (visibleHeight - size().height()) / 2; |
| setY(top); |
| dialog->setCentered(top); |
| } |
| |
| } // namespace blink |