| /* |
| * 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/rendering/RenderBlockFlow.h" |
| |
| #include "core/page/FrameView.h" |
| #include "core/rendering/LayoutRepainter.h" |
| #include "core/rendering/RenderLayer.h" |
| #include "core/rendering/RenderNamedFlowThread.h" |
| #include "core/rendering/RenderView.h" |
| |
| using namespace std; |
| |
| namespace WebCore { |
| |
| struct SameSizeAsMarginInfo { |
| uint16_t bitfields; |
| LayoutUnit margins[2]; |
| }; |
| |
| COMPILE_ASSERT(sizeof(RenderBlockFlow::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; |
| |
| // 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; |
| |
| // These flags track the previous maximal positive and negative margins. |
| LayoutUnit m_positiveMargin; |
| LayoutUnit m_negativeMargin; |
| |
| public: |
| MarginInfo(RenderBlockFlow*, 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 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 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; } |
| }; |
| |
| static bool inNormalFlow(RenderBox* child) |
| { |
| RenderBlock* curr = child->containingBlock(); |
| RenderView* renderView = child->view(); |
| while (curr && curr != renderView) { |
| if (curr->hasColumns() || curr->isRenderFlowThread()) |
| return true; |
| if (curr->isFloatingOrOutOfFlowPositioned()) |
| return false; |
| curr = curr->containingBlock(); |
| } |
| return true; |
| } |
| |
| RenderBlockFlow::RenderBlockFlow(ContainerNode* node) |
| : RenderBlock(node) |
| { |
| COMPILE_ASSERT(sizeof(MarginInfo) == sizeof(SameSizeAsMarginInfo), MarginInfo_should_stay_small); |
| } |
| |
| RenderBlockFlow::~RenderBlockFlow() |
| { |
| } |
| |
| void RenderBlockFlow::layoutBlock(bool relayoutChildren, LayoutUnit pageLogicalHeight) |
| { |
| ASSERT(needsLayout()); |
| |
| if (isInline() && !isInlineBlockOrInlineTable()) // Inline <form>s inside various table elements can cause us to come in here. Bail. |
| return; |
| |
| if (!relayoutChildren && simplifiedLayout()) |
| return; |
| |
| LayoutRepainter repainter(*this, checkForRepaintDuringLayout()); |
| |
| if (updateLogicalWidthAndColumnWidth()) |
| relayoutChildren = true; |
| |
| clearFloats(); |
| |
| LayoutUnit previousHeight = logicalHeight(); |
| // FIXME: should this start out as borderAndPaddingLogicalHeight() + scrollbarLogicalHeight(), |
| // for consistency with other render classes? |
| setLogicalHeight(0); |
| |
| bool pageLogicalHeightChanged = false; |
| bool hasSpecifiedPageLogicalHeight = false; |
| checkForPaginationLogicalHeightChange(pageLogicalHeight, pageLogicalHeightChanged, hasSpecifiedPageLogicalHeight); |
| |
| RenderView* renderView = view(); |
| RenderStyle* styleToUse = style(); |
| LayoutStateMaintainer statePusher(renderView, this, locationOffset(), hasColumns() || hasTransform() || hasReflection() || styleToUse->isFlippedBlocksWritingMode(), pageLogicalHeight, pageLogicalHeightChanged, columnInfo()); |
| |
| // Regions changing widths can force us to relayout our children. |
| RenderFlowThread* flowThread = flowThreadContainingBlock(); |
| if (logicalWidthChangedInRegions(flowThread)) |
| relayoutChildren = true; |
| if (updateRegionsAndShapesLogicalSize(flowThread)) |
| relayoutChildren = true; |
| |
| // 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. |
| bool isCell = isTableCell(); |
| if (!isCell) { |
| initMaxMarginValues(); |
| |
| setHasMarginBeforeQuirk(styleToUse->hasMarginBeforeQuirk()); |
| setHasMarginAfterQuirk(styleToUse->hasMarginAfterQuirk()); |
| setPaginationStrut(0); |
| } |
| |
| SubtreeLayoutScope layoutScope(this); |
| |
| LayoutUnit repaintLogicalTop = 0; |
| LayoutUnit repaintLogicalBottom = 0; |
| LayoutUnit maxFloatLogicalBottom = 0; |
| if (!firstChild() && !isAnonymousBlock()) |
| setChildrenInline(true); |
| if (childrenInline()) |
| layoutInlineChildren(relayoutChildren, repaintLogicalTop, repaintLogicalBottom); |
| else |
| layoutBlockChildren(relayoutChildren, maxFloatLogicalBottom, layoutScope); |
| |
| if (frameView()->partialLayout().isStopping()) { |
| statePusher.pop(); |
| return; |
| } |
| |
| // Expand our intrinsic height to encompass floats. |
| LayoutUnit toAdd = borderAfter() + paddingAfter() + scrollbarLogicalHeight(); |
| if (lowestFloatLogicalBottom() > (logicalHeight() - toAdd) && expandsToEncloseOverhangingFloats()) |
| setLogicalHeight(lowestFloatLogicalBottom() + toAdd); |
| |
| if (relayoutForPagination(hasSpecifiedPageLogicalHeight, pageLogicalHeight, statePusher)) |
| return; |
| |
| // Calculate our new height. |
| LayoutUnit oldHeight = logicalHeight(); |
| LayoutUnit oldClientAfterEdge = clientLogicalBottom(); |
| |
| // Before updating the final size of the flow thread make sure a forced break is applied after the content. |
| // This ensures the size information is correctly computed for the last auto-height region receiving content. |
| if (isRenderFlowThread()) |
| toRenderFlowThread(this)->applyBreakAfterContent(oldClientAfterEdge); |
| |
| updateLogicalHeight(); |
| LayoutUnit newHeight = logicalHeight(); |
| if (oldHeight != newHeight) { |
| if (oldHeight > newHeight && maxFloatLogicalBottom > newHeight && !childrenInline()) { |
| // One of our children's floats may have become an overhanging float for us. We need to look for it. |
| for (RenderObject* child = firstChild(); child; child = child->nextSibling()) { |
| if (child->isRenderBlockFlow() && !child->isFloatingOrOutOfFlowPositioned()) { |
| RenderBlock* block = toRenderBlock(child); |
| if (block->lowestFloatLogicalBottom() + block->logicalTop() > newHeight) |
| addOverhangingFloats(block, false); |
| } |
| } |
| } |
| } |
| |
| bool heightChanged = (previousHeight != newHeight); |
| if (heightChanged) |
| relayoutChildren = true; |
| |
| layoutPositionedObjects(relayoutChildren || isRoot()); |
| |
| updateRegionsAndShapesAfterChildLayout(flowThread, heightChanged); |
| |
| // Add overflow from children (unless we're multi-column, since in that case all our child overflow is clipped anyway). |
| computeOverflow(oldClientAfterEdge); |
| |
| statePusher.pop(); |
| |
| fitBorderToLinesIfNeeded(); |
| |
| if (frameView()->partialLayout().isStopping()) |
| return; |
| |
| if (renderView->layoutState()->m_pageLogicalHeight) |
| setPageLogicalOffset(renderView->layoutState()->pageLogicalOffset(this, logicalTop())); |
| |
| updateLayerTransform(); |
| |
| // Update our scroll information if we're overflow:auto/scroll/hidden now that we know if |
| // we overflow or not. |
| updateScrollInfoAfterLayout(); |
| |
| // FIXME: This repaint logic should be moved into a separate helper function! |
| // Repaint with our new bounds if they are different from our old bounds. |
| bool didFullRepaint = repainter.repaintAfterLayout(); |
| if (!didFullRepaint && repaintLogicalTop != repaintLogicalBottom && (styleToUse->visibility() == VISIBLE || enclosingLayer()->hasVisibleContent())) { |
| // 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 repaintLogicalLeft = logicalLeftVisualOverflow(); |
| LayoutUnit repaintLogicalRight = 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 repaint rect. |
| repaintLogicalLeft = min(repaintLogicalLeft, logicalLeftLayoutOverflow()); |
| repaintLogicalRight = max(repaintLogicalRight, logicalRightLayoutOverflow()); |
| } |
| |
| LayoutRect repaintRect; |
| if (isHorizontalWritingMode()) |
| repaintRect = LayoutRect(repaintLogicalLeft, repaintLogicalTop, repaintLogicalRight - repaintLogicalLeft, repaintLogicalBottom - repaintLogicalTop); |
| else |
| repaintRect = LayoutRect(repaintLogicalTop, repaintLogicalLeft, repaintLogicalBottom - repaintLogicalTop, repaintLogicalRight - repaintLogicalLeft); |
| |
| // The repaint rect may be split across columns, in which case adjustRectForColumns() will return the union. |
| adjustRectForColumns(repaintRect); |
| |
| repaintRect.inflate(maximalOutlineSize(PaintPhaseOutline)); |
| |
| if (hasOverflowClip()) { |
| // Adjust repaint rect for scroll offset |
| repaintRect.move(-scrolledContentOffset()); |
| |
| // Don't allow this rect to spill out of our overflow box. |
| repaintRect.intersect(LayoutRect(LayoutPoint(), size())); |
| } |
| |
| // Make sure the rect is still non-empty after intersecting for overflow above |
| if (!repaintRect.isEmpty()) { |
| repaintRectangle(repaintRect); // We need to do a partial repaint of our content. |
| if (hasReflection()) |
| repaintRectangle(reflectedRect(repaintRect)); |
| } |
| } |
| |
| clearNeedsLayout(); |
| } |
| |
| void RenderBlockFlow::layoutBlockChild(RenderBox* child, MarginInfo& marginInfo, LayoutUnit& previousFloatLogicalBottom, LayoutUnit& maxFloatLogicalBottom) |
| { |
| 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 repaint rects if the child moves. |
| LayoutRect oldRect = child->frameRect(); |
| LayoutUnit oldLogicalTop = logicalTopForChild(child); |
| |
| #if !ASSERT_DISABLED |
| LayoutSize oldLayoutDelta = view()->layoutDelta(); |
| #endif |
| // Go ahead and position the child as though it didn't collapse with the top. |
| setLogicalTopForChild(child, logicalTopEstimate, ApplyLayoutDelta); |
| |
| RenderBlock* childRenderBlock = child->isRenderBlock() ? toRenderBlock(child) : 0; |
| bool markDescendantsWithFloats = false; |
| if (logicalTopEstimate != oldLogicalTop && !child->avoidsFloats() && childRenderBlock && childRenderBlock->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 = max(previousFloatLogicalBottom, lowestFloatLogicalBottom()); |
| if (fb > logicalTopEstimate) |
| markDescendantsWithFloats = true; |
| } |
| |
| if (childRenderBlock) { |
| if (markDescendantsWithFloats) |
| childRenderBlock->markAllDescendantsWithFloatsForLayout(); |
| if (!child->isWritingModeRoot()) |
| previousFloatLogicalBottom = max(previousFloatLogicalBottom, oldLogicalTop + childRenderBlock->lowestFloatLogicalBottom()); |
| } |
| |
| SubtreeLayoutScope layoutScope(child); |
| if (!child->needsLayout()) |
| child->markForPaginationRelayoutIfNeeded(layoutScope); |
| |
| bool childHadLayout = child->everHadLayout(); |
| bool childNeededLayout = child->needsLayout(); |
| if (childNeededLayout) |
| child->layout(); |
| |
| if (frameView()->partialLayout().isStopping()) |
| return; |
| |
| // Cache if we are at the top of the block right now. |
| bool atBeforeSideOfBlock = marginInfo.atBeforeSideOfBlock(); |
| |
| // Now determine the correct ypos based off examination of collapsing margin |
| // values. |
| LayoutUnit logicalTopBeforeClear = collapseMargins(child, marginInfo); |
| |
| // Now check for clear. |
| LayoutUnit logicalTopAfterClear = clearFloatsIfNeeded(child, marginInfo, oldPosMarginBefore, oldNegMarginBefore, logicalTopBeforeClear); |
| |
| bool paginated = view()->layoutState()->isPaginated(); |
| if (paginated) { |
| logicalTopAfterClear = adjustBlockChildForPagination(logicalTopAfterClear, estimateWithoutPagination, child, |
| atBeforeSideOfBlock && logicalTopBeforeClear == logicalTopAfterClear); |
| } |
| |
| setLogicalTopForChild(child, logicalTopAfterClear, ApplyLayoutDelta); |
| |
| // 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 && childRenderBlock && childRenderBlock->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 (childRenderBlock) { |
| if (!child->avoidsFloats() && childRenderBlock->containsFloats()) |
| childRenderBlock->markAllDescendantsWithFloatsForLayout(); |
| if (!child->needsLayout()) |
| child->markForPaginationRelayoutIfNeeded(layoutScope); |
| } |
| |
| // Our guess was wrong. Make the child lay itself out again. |
| child->layoutIfNeeded(); |
| } |
| |
| // 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() && !child->isSelfCollapsingBlock()) |
| marginInfo.setAtBeforeSideOfBlock(false); |
| |
| // Now place the child in the correct left position |
| determineLogicalLeftPositionForChild(child, ApplyLayoutDelta); |
| |
| LayoutSize childOffset = child->location() - oldRect.location(); |
| relayoutShapeDescendantIfMoved(childRenderBlock, childOffset); |
| |
| // 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 (childRenderBlock && childRenderBlock->containsFloats()) |
| maxFloatLogicalBottom = max(maxFloatLogicalBottom, addOverhangingFloats(toRenderBlock(child), !childNeededLayout)); |
| |
| if (childOffset.width() || childOffset.height()) { |
| view()->addLayoutDelta(childOffset); |
| |
| // If the child moved, we have to repaint it as well as any floating/positioned |
| // descendants. An exception is if we need a layout. In this case, we know we're going to |
| // repaint ourselves (and the child) anyway. |
| if (childHadLayout && !selfNeedsLayout() && child->checkForRepaintDuringLayout()) |
| child->repaintDuringLayoutIfMoved(oldRect); |
| } |
| |
| if (!childHadLayout && child->checkForRepaintDuringLayout()) { |
| child->repaint(); |
| child->repaintOverhangingFloats(true); |
| } |
| |
| if (paginated) { |
| // Check for an after page/column break. |
| LayoutUnit newHeight = applyAfterBreak(child, logicalHeight(), marginInfo); |
| if (newHeight != height()) |
| setLogicalHeight(newHeight); |
| } |
| |
| ASSERT(view()->layoutDeltaMatches(oldLayoutDelta)); |
| } |
| |
| LayoutUnit RenderBlockFlow::adjustBlockChildForPagination(LayoutUnit logicalTopAfterClear, LayoutUnit estimateWithoutPagination, RenderBox* child, bool atBeforeSideOfBlock) |
| { |
| RenderBlock* childRenderBlock = child->isRenderBlock() ? toRenderBlock(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, ApplyLayoutDelta); |
| |
| 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 (childRenderBlock) { |
| if (!child->avoidsFloats() && childRenderBlock->containsFloats()) |
| childRenderBlock->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); |
| |
| if (pageLogicalHeightForOffset(result)) { |
| LayoutUnit remainingLogicalHeight = pageRemainingLogicalHeightForOffset(result, ExcludePageBoundary); |
| LayoutUnit spaceShortage = child->logicalHeight() - 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. FIXME: |
| // This should be improved, though, because here we just pretend that the child is |
| // unsplittable. A splittable child, on the other hand, has break opportunities at every position |
| // where there's no child content, border or padding. In other words, we risk stretching more |
| // than necessary. |
| setPageBreak(result, spaceShortage); |
| } |
| } |
| |
| // 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; |
| if (unsplittableAdjustmentDelta) |
| paginationStrut = unsplittableAdjustmentDelta; |
| else if (childRenderBlock && childRenderBlock->paginationStrut()) |
| paginationStrut = childRenderBlock->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 (childRenderBlock) |
| childRenderBlock->setPaginationStrut(0); |
| } else { |
| result += paginationStrut; |
| } |
| } |
| |
| // 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; |
| } |
| |
| void RenderBlockFlow::clearFloats() |
| { |
| if (m_floatingObjects) |
| m_floatingObjects->setHorizontalWritingMode(isHorizontalWritingMode()); |
| |
| HashSet<RenderBox*> oldIntrudingFloatSet; |
| if (!childrenInline() && m_floatingObjects) { |
| const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set(); |
| FloatingObjectSetIterator end = floatingObjectSet.end(); |
| for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) { |
| FloatingObject* floatingObject = *it; |
| if (!floatingObject->isDescendant()) |
| oldIntrudingFloatSet.add(floatingObject->renderer()); |
| } |
| } |
| |
| // Inline blocks are covered by the isReplaced() check in the avoidFloats method. |
| if (avoidsFloats() || isRoot() || isRenderView() || isFloatingOrOutOfFlowPositioned() || isTableCell()) { |
| if (m_floatingObjects) { |
| m_floatingObjects->clear(); |
| } |
| if (!oldIntrudingFloatSet.isEmpty()) |
| markAllDescendantsWithFloatsForLayout(); |
| return; |
| } |
| |
| RendererToFloatInfoMap 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 RenderBlock. 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()->isRenderBlock()) |
| return; |
| |
| // Attempt to locate a previous sibling with overhanging floats. We skip any elements that are |
| // out of flow (like floating/positioned elements), and we also skip over any objects that may have shifted |
| // to avoid floats. |
| RenderBlock* parentBlock = toRenderBlock(parent()); |
| bool parentHasFloats = false; |
| RenderObject* prev = previousSibling(); |
| while (prev && (prev->isFloatingOrOutOfFlowPositioned() || !prev->isBox() || !prev->isRenderBlock() || toRenderBlock(prev)->avoidsFloats())) { |
| if (prev->isFloating()) |
| parentHasFloats = true; |
| prev = prev->previousSibling(); |
| } |
| |
| // First add in floats from the parent. |
| LayoutUnit logicalTopOffset = logicalTop(); |
| if (parentHasFloats) |
| addIntrudingFloats(parentBlock, parentBlock->logicalLeftOffsetForContent(), logicalTopOffset); |
| |
| LayoutUnit logicalLeftOffset = 0; |
| if (prev) { |
| logicalTopOffset -= toRenderBox(prev)->logicalTop(); |
| } else { |
| prev = parentBlock; |
| logicalLeftOffset += parentBlock->logicalLeftOffsetForContent(); |
| } |
| |
| // Add overhanging floats from the previous RenderBlock, but only if it has a float that intrudes into our space. |
| RenderBlock* block = toRenderBlock(prev); |
| if (block->m_floatingObjects && block->lowestFloatLogicalBottom() > logicalTopOffset) |
| addIntrudingFloats(block, logicalLeftOffset, 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) { |
| FloatingObject* f = *it; |
| FloatingObject* oldFloatingObject = floatMap.get(f->renderer()); |
| LayoutUnit logicalBottom = f->logicalBottom(isHorizontalWritingMode()); |
| if (oldFloatingObject) { |
| LayoutUnit oldLogicalBottom = oldFloatingObject->logicalBottom(isHorizontalWritingMode()); |
| if (f->logicalWidth(isHorizontalWritingMode()) != oldFloatingObject->logicalWidth(isHorizontalWritingMode()) || f->logicalLeft(isHorizontalWritingMode()) != oldFloatingObject->logicalLeft(isHorizontalWritingMode())) { |
| changeLogicalTop = 0; |
| changeLogicalBottom = max(changeLogicalBottom, max(logicalBottom, oldLogicalBottom)); |
| } else { |
| if (logicalBottom != oldLogicalBottom) { |
| changeLogicalTop = min(changeLogicalTop, min(logicalBottom, oldLogicalBottom)); |
| changeLogicalBottom = max(changeLogicalBottom, max(logicalBottom, oldLogicalBottom)); |
| } |
| LayoutUnit logicalTop = f->logicalTop(isHorizontalWritingMode()); |
| LayoutUnit oldLogicalTop = oldFloatingObject->logicalTop(isHorizontalWritingMode()); |
| if (logicalTop != oldLogicalTop) { |
| changeLogicalTop = min(changeLogicalTop, min(logicalTop, oldLogicalTop)); |
| changeLogicalBottom = max(changeLogicalBottom, max(logicalTop, oldLogicalTop)); |
| } |
| } |
| |
| floatMap.remove(f->renderer()); |
| if (oldFloatingObject->originatingLine() && !selfNeedsLayout()) { |
| ASSERT(oldFloatingObject->originatingLine()->renderer() == this); |
| oldFloatingObject->originatingLine()->markDirty(); |
| } |
| delete oldFloatingObject; |
| } else { |
| changeLogicalTop = 0; |
| changeLogicalBottom = max(changeLogicalBottom, logicalBottom); |
| } |
| } |
| } |
| |
| RendererToFloatInfoMap::iterator end = floatMap.end(); |
| for (RendererToFloatInfoMap::iterator it = floatMap.begin(); it != end; ++it) { |
| FloatingObject* floatingObject = (*it).value; |
| if (!floatingObject->isDescendant()) { |
| changeLogicalTop = 0; |
| changeLogicalBottom = max(changeLogicalBottom, floatingObject->logicalBottom(isHorizontalWritingMode())); |
| } |
| } |
| deleteAllValues(floatMap); |
| |
| 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)->renderer()); |
| if (!oldIntrudingFloatSet.isEmpty()) |
| markAllDescendantsWithFloatsForLayout(); |
| } |
| } |
| } |
| |
| void RenderBlockFlow::layoutBlockChildren(bool relayoutChildren, LayoutUnit& maxFloatLogicalBottom, SubtreeLayoutScope& layoutScope) |
| { |
| dirtyForLayoutFromPercentageHeightDescendants(layoutScope); |
| |
| LayoutUnit beforeEdge = borderBefore() + paddingBefore(); |
| LayoutUnit afterEdge = borderAfter() + paddingAfter() + scrollbarLogicalHeight(); |
| |
| setLogicalHeight(beforeEdge); |
| |
| // Lay out our hypothetical grid line as though it occurs at the top of the block. |
| if (view()->layoutState()->lineGrid() == this) |
| layoutLineGridBox(); |
| |
| // 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. |
| RenderObject* childToExclude = layoutSpecialExcludedChild(relayoutChildren, layoutScope); |
| |
| LayoutUnit previousFloatLogicalBottom = 0; |
| maxFloatLogicalBottom = 0; |
| |
| RenderBox* next = firstChildBox(); |
| |
| while (next) { |
| RenderBox* child = next; |
| next = child->nextSiblingBox(); |
| |
| 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; |
| } |
| |
| // Lay out the child. |
| layoutBlockChild(child, marginInfo, previousFloatLogicalBottom, maxFloatLogicalBottom); |
| |
| // If doing a partial layout and the child was the target renderer, early exit here. |
| if (frameView()->partialLayout().checkPartialLayoutComplete(child)) |
| break; |
| } |
| |
| // 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(beforeEdge, afterEdge, marginInfo); |
| } |
| |
| // Our MarginInfo state used when laying out block children. |
| MarginInfo::MarginInfo(RenderBlockFlow* blockFlow, LayoutUnit beforeBorderPadding, LayoutUnit afterBorderPadding) |
| : m_atBeforeSideOfBlock(true) |
| , m_atAfterSideOfBlock(false) |
| , m_hasMarginBeforeQuirk(false) |
| , m_hasMarginAfterQuirk(false) |
| , m_determinedMarginBeforeQuirk(false) |
| , m_discardMargin(false) |
| { |
| RenderStyle* blockStyle = blockFlow->style(); |
| ASSERT(blockFlow->isRenderView() || blockFlow->parent()); |
| m_canCollapseWithChildren = !blockFlow->isRenderView() && !blockFlow->isRoot() && !blockFlow->isOutOfFlowPositioned() |
| && !blockFlow->isFloating() && !blockFlow->isTableCell() && !blockFlow->hasOverflowClip() && !blockFlow->isInlineBlockOrInlineTable() |
| && !blockFlow->isRenderFlowThread() && !blockFlow->isWritingModeRoot() && !blockFlow->parent()->isFlexibleBox() |
| && blockStyle->hasAutoColumnCount() && blockStyle->hasAutoColumnWidth() && !blockStyle->columnSpan(); |
| |
| 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(); |
| } |
| |
| RenderBlockFlow::MarginValues RenderBlockFlow::marginValuesForChild(RenderBox* child) const |
| { |
| LayoutUnit childBeforePositive = 0; |
| LayoutUnit childBeforeNegative = 0; |
| LayoutUnit childAfterPositive = 0; |
| LayoutUnit childAfterNegative = 0; |
| |
| LayoutUnit beforeMargin = 0; |
| LayoutUnit afterMargin = 0; |
| |
| RenderBlockFlow* childRenderBlockFlow = child->isRenderBlockFlow() ? toRenderBlockFlow(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 (childRenderBlockFlow) { |
| childBeforePositive = childRenderBlockFlow->maxPositiveMarginBefore(); |
| childBeforeNegative = childRenderBlockFlow->maxNegativeMarginBefore(); |
| childAfterPositive = childRenderBlockFlow->maxPositiveMarginAfter(); |
| childAfterNegative = childRenderBlockFlow->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 (childRenderBlockFlow) { |
| childBeforePositive = childRenderBlockFlow->maxPositiveMarginAfter(); |
| childBeforeNegative = childRenderBlockFlow->maxNegativeMarginAfter(); |
| childAfterPositive = childRenderBlockFlow->maxPositiveMarginBefore(); |
| childAfterNegative = childRenderBlockFlow->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 RenderBlockFlow::MarginValues(childBeforePositive, childBeforeNegative, childAfterPositive, childAfterNegative); |
| } |
| |
| LayoutUnit RenderBlockFlow::collapseMargins(RenderBox* child, MarginInfo& marginInfo) |
| { |
| bool childDiscardMarginBefore = mustDiscardMarginBeforeForChild(child); |
| bool childDiscardMarginAfter = mustDiscardMarginAfterForChild(child); |
| bool childIsSelfCollapsing = child->isSelfCollapsingBlock(); |
| |
| // 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 RenderBlockFlow::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 = max(posTop, childMargins.positiveMarginAfter()); |
| negTop = 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(max(posTop, maxPositiveMarginBefore()), 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; |
| 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 = max(marginInfo.positiveMargin(), childMargins.positiveMarginBefore()); |
| LayoutUnit collapsedBeforeNeg = 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(0); |
| 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() + max(marginInfo.positiveMargin(), posTop) - 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() && layoutState->pageLogicalHeight() && logicalTop > beforeCollapseLogicalTop |
| && hasNextPage(beforeCollapseLogicalTop)) { |
| LayoutUnit oldLogicalTop = logicalTop; |
| logicalTop = min(logicalTop, nextPageLogicalTop(beforeCollapseLogicalTop)); |
| setLogicalHeight(logicalHeight() + (logicalTop - oldLogicalTop)); |
| } |
| |
| // If we have collapsed into a previous sibling and so reduced the height of the parent, ensure any floats that now |
| // overhang from the previous sibling are added to our parent. If the child's previous sibling itself is a float the child will avoid |
| // or clear it anyway, so don't worry about any floating children it may contain. |
| LayoutUnit oldLogicalHeight = logicalHeight(); |
| setLogicalHeight(logicalTop); |
| RenderObject* prev = child->previousSibling(); |
| if (prev && prev->isRenderBlockFlow() && !prev->isFloatingOrOutOfFlowPositioned()) { |
| RenderBlockFlow* blockFlow = toRenderBlockFlow(prev); |
| if (blockFlow->containsFloats() && !blockFlow->avoidsFloats() && (blockFlow->logicalTop() + blockFlow->lowestFloatLogicalBottom()) > logicalTop) |
| addOverhangingFloats(blockFlow, false); |
| } |
| setLogicalHeight(oldLogicalHeight); |
| |
| return logicalTop; |
| } |
| |
| void RenderBlockFlow::adjustPositionedBlock(RenderBox* child, const MarginInfo& marginInfo) |
| { |
| bool isHorizontal = isHorizontalWritingMode(); |
| bool hasStaticBlockPosition = child->style()->hasStaticBlockPosition(isHorizontal); |
| |
| 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; |
| } |
| |
| RenderLayer* childLayer = child->layer(); |
| if (childLayer->staticBlockPosition() != logicalTop) { |
| childLayer->setStaticBlockPosition(logicalTop); |
| if (hasStaticBlockPosition) |
| child->setChildNeedsLayout(MarkOnlyThis); |
| } |
| } |
| |
| LayoutUnit RenderBlockFlow::clearFloatsIfNeeded(RenderBox* child, MarginInfo& marginInfo, LayoutUnit oldTopPosMargin, LayoutUnit oldTopNegMargin, LayoutUnit yPos) |
| { |
| LayoutUnit heightIncrease = getClearDelta(child, yPos); |
| if (!heightIncrease) |
| return yPos; |
| |
| if (child->isSelfCollapsingBlock()) { |
| bool childDiscardMargin = mustDiscardMarginBeforeForChild(child) || mustDiscardMarginAfterForChild(child); |
| |
| // 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. |
| if (!childDiscardMargin) { |
| RenderBlockFlow::MarginValues childMargins = marginValuesForChild(child); |
| marginInfo.setPositiveMargin(max(childMargins.positiveMarginBefore(), childMargins.positiveMarginAfter())); |
| marginInfo.setNegativeMargin(max(childMargins.negativeMarginBefore(), childMargins.negativeMarginAfter())); |
| } else { |
| marginInfo.clearMargin(); |
| } |
| marginInfo.setDiscardMargin(childDiscardMargin); |
| |
| // 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. Check subsequent siblings |
| // for a block with height - if none is found then don't allow the margins to collapse with the parent. |
| bool wouldCollapseMarginsWithParent = marginInfo.canCollapseMarginAfterWithChildren(); |
| for (RenderBox* curr = child->nextSiblingBox(); curr && wouldCollapseMarginsWithParent; curr = curr->nextSiblingBox()) { |
| if (!curr->isFloatingOrOutOfFlowPositioned() && !curr->isSelfCollapsingBlock()) |
| wouldCollapseMarginsWithParent = false; |
| } |
| if (wouldCollapseMarginsWithParent) |
| marginInfo.setCanCollapseMarginAfterWithChildren(false); |
| |
| // CSS2.1: "the amount of clearance is set so that clearance + margin-top = [height of float], i.e., clearance = [height of float] - margin-top" |
| // Move the top of the child box to the bottom of the float ignoring the child's top margin. |
| LayoutUnit collapsedMargin = collapsedMarginBeforeForChild(child); |
| setLogicalHeight(child->logicalTop() - collapsedMargin); |
| // A negative collapsed margin-top value cancels itself out as it has already been factored into |yPos| above. |
| heightIncrease -= max(LayoutUnit(), collapsedMargin); |
| } 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. |
| // FIXME: This isn't quite correct. Need clarification for what to do |
| // if the height the cleared block is offset by is smaller than the |
| // margins involved. |
| 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); |
| } |
| |
| LayoutUnit logicalTop = yPos + heightIncrease; |
| // After margin collapsing, one of our floats may now intrude into the child. If the child doesn't contain floats of its own it |
| // won't get picked up for relayout even though the logical top estimate was wrong - so add the newly intruding float now. |
| if (containsFloats() && child->isRenderBlock() && !toRenderBlock(child)->containsFloats() && !child->avoidsFloats() && lowestFloatLogicalBottom() > logicalTop) |
| toRenderBlock(child)->addIntrudingFloats(this, logicalLeftOffsetForContent(), logicalTop); |
| |
| return logicalTop; |
| } |
| |
| void RenderBlockFlow::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(max(maxPositiveMarginAfter(), marginInfo.positiveMargin()), 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 RenderBlockFlow::marginBeforeEstimateForChild(RenderBox* 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() && hasMarginAfterQuirk(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 = max(positiveMarginBefore, beforeChildMargin); |
| negativeMarginBefore = max(negativeMarginBefore, -beforeChildMargin); |
| |
| if (!child->isRenderBlockFlow()) |
| return; |
| |
| RenderBlockFlow* childBlockFlow = toRenderBlockFlow(child); |
| if (childBlockFlow->childrenInline() || childBlockFlow->isWritingModeRoot()) |
| return; |
| |
| MarginInfo childMarginInfo(childBlockFlow, childBlockFlow->borderBefore() + childBlockFlow->paddingBefore(), childBlockFlow->borderAfter() + childBlockFlow->paddingAfter()); |
| if (!childMarginInfo.canCollapseMarginBeforeWithChildren()) |
| return; |
| |
| RenderBox* grandchildBox = childBlockFlow->firstChildBox(); |
| for ( ; grandchildBox; grandchildBox = grandchildBox->nextSiblingBox()) { |
| if (!grandchildBox->isFloatingOrOutOfFlowPositioned()) |
| break; |
| } |
| |
| // Give up if there is clearance on the box, since it probably won't collapse into us. |
| if (!grandchildBox || grandchildBox->style()->clear() != CNONE) |
| 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->isRenderBlock()) { |
| RenderBlock* grandchildBlock = toRenderBlock(grandchildBox); |
| grandchildBlock->setHasMarginBeforeQuirk(grandchildBox->style()->hasMarginBeforeQuirk()); |
| grandchildBlock->setHasMarginAfterQuirk(grandchildBox->style()->hasMarginAfterQuirk()); |
| } |
| } |
| |
| // Collapse the margin of the grandchild box with our own to produce an estimate. |
| childBlockFlow->marginBeforeEstimateForChild(grandchildBox, positiveMarginBefore, negativeMarginBefore, discardMarginBefore); |
| } |
| |
| LayoutUnit RenderBlockFlow::estimateLogicalTopPosition(RenderBox* 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. |
| RenderBlockFlow::MarginValues marginValues = marginValuesForChild(child); |
| positiveMarginBefore = max(positiveMarginBefore, marginValues.positiveMarginBefore()); |
| negativeMarginBefore = max(negativeMarginBefore, marginValues.negativeMarginBefore()); |
| discardMarginBefore = mustDiscardMarginBeforeForChild(child); |
| } |
| |
| // Collapse the result with our current margins. |
| if (!discardMarginBefore) |
| logicalTopEstimate += max(marginInfo.positiveMargin(), positiveMarginBefore) - 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() && layoutState->pageLogicalHeight() && logicalTopEstimate > logicalHeight() |
| && hasNextPage(logicalHeight())) |
| logicalTopEstimate = 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->isRenderBlock()) |
| logicalTopEstimate += toRenderBlock(child)->paginationStrut(); |
| } |
| |
| return logicalTopEstimate; |
| } |
| |
| void RenderBlockFlow::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 RenderBlockFlow::handleAfterSideOfBlock(LayoutUnit beforeSide, LayoutUnit afterSide, MarginInfo& marginInfo) |
| { |
| marginInfo.setAtAfterSideOfBlock(true); |
| |
| // 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(max(logicalHeight(), beforeSide + afterSide)); |
| |
| // Update our bottom collapsed margin info. |
| setCollapsedBottomMargin(marginInfo); |
| } |
| |
| void RenderBlockFlow::setMustDiscardMarginBefore(bool value) |
| { |
| if (style()->marginBeforeCollapse() == MDISCARD) { |
| ASSERT(value); |
| return; |
| } |
| |
| if (!m_rareData && !value) |
| return; |
| |
| if (!m_rareData) |
| m_rareData = adoptPtr(new RenderBlockFlowRareData(this)); |
| |
| m_rareData->m_discardMarginBefore = value; |
| } |
| |
| void RenderBlockFlow::setMustDiscardMarginAfter(bool value) |
| { |
| if (style()->marginAfterCollapse() == MDISCARD) { |
| ASSERT(value); |
| return; |
| } |
| |
| if (!m_rareData && !value) |
| return; |
| |
| if (!m_rareData) |
| m_rareData = adoptPtr(new RenderBlockFlowRareData(this)); |
| |
| m_rareData->m_discardMarginAfter = value; |
| } |
| |
| bool RenderBlockFlow::mustDiscardMarginBefore() const |
| { |
| return style()->marginBeforeCollapse() == MDISCARD || (m_rareData && m_rareData->m_discardMarginBefore); |
| } |
| |
| bool RenderBlockFlow::mustDiscardMarginAfter() const |
| { |
| return style()->marginAfterCollapse() == MDISCARD || (m_rareData && m_rareData->m_discardMarginAfter); |
| } |
| |
| bool RenderBlockFlow::mustDiscardMarginBeforeForChild(const RenderBox* child) const |
| { |
| ASSERT(!child->selfNeedsLayout()); |
| if (!child->isWritingModeRoot()) |
| return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginBefore() : (child->style()->marginBeforeCollapse() == MDISCARD); |
| if (child->isHorizontalWritingMode() == isHorizontalWritingMode()) |
| return child->isRenderBlockFlow() ? toRenderBlockFlow(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 RenderBlockFlow::mustDiscardMarginAfterForChild(const RenderBox* child) const |
| { |
| ASSERT(!child->selfNeedsLayout()); |
| if (!child->isWritingModeRoot()) |
| return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginAfter() : (child->style()->marginAfterCollapse() == MDISCARD); |
| if (child->isHorizontalWritingMode() == isHorizontalWritingMode()) |
| return child->isRenderBlockFlow() ? toRenderBlockFlow(child)->mustDiscardMarginBefore() : (child->style()->marginBeforeCollapse() == MDISCARD); |
| |
| // FIXME: See |mustDiscardMarginBeforeForChild| above. |
| return false; |
| } |
| |
| void RenderBlockFlow::setMaxMarginBeforeValues(LayoutUnit pos, LayoutUnit neg) |
| { |
| if (!m_rareData) { |
| if (pos == RenderBlockFlowRareData::positiveMarginBeforeDefault(this) && neg == RenderBlockFlowRareData::negativeMarginBeforeDefault(this)) |
| return; |
| m_rareData = adoptPtr(new RenderBlockFlowRareData(this)); |
| } |
| m_rareData->m_margins.setPositiveMarginBefore(pos); |
| m_rareData->m_margins.setNegativeMarginBefore(neg); |
| } |
| |
| void RenderBlockFlow::setMaxMarginAfterValues(LayoutUnit pos, LayoutUnit neg) |
| { |
| if (!m_rareData) { |
| if (pos == RenderBlockFlowRareData::positiveMarginAfterDefault(this) && neg == RenderBlockFlowRareData::negativeMarginAfterDefault(this)) |
| return; |
| m_rareData = adoptPtr(new RenderBlockFlowRareData(this)); |
| } |
| m_rareData->m_margins.setPositiveMarginAfter(pos); |
| m_rareData->m_margins.setNegativeMarginAfter(neg); |
| } |
| |
| bool RenderBlockFlow::mustSeparateMarginBeforeForChild(const RenderBox* child) const |
| { |
| ASSERT(!child->selfNeedsLayout()); |
| const RenderStyle* childStyle = child->style(); |
| if (!child->isWritingModeRoot()) |
| return childStyle->marginBeforeCollapse() == MSEPARATE; |
| if (child->isHorizontalWritingMode() == isHorizontalWritingMode()) |
| return childStyle->marginAfterCollapse() == MSEPARATE; |
| |
| // FIXME: See |mustDiscardMarginBeforeForChild| above. |
| return false; |
| } |
| |
| bool RenderBlockFlow::mustSeparateMarginAfterForChild(const RenderBox* child) const |
| { |
| ASSERT(!child->selfNeedsLayout()); |
| const RenderStyle* childStyle = child->style(); |
| if (!child->isWritingModeRoot()) |
| return childStyle->marginAfterCollapse() == MSEPARATE; |
| if (child->isHorizontalWritingMode() == isHorizontalWritingMode()) |
| return childStyle->marginBeforeCollapse() == MSEPARATE; |
| |
| // FIXME: See |mustDiscardMarginBeforeForChild| above. |
| return false; |
| } |
| |
| LayoutUnit RenderBlockFlow::applyBeforeBreak(RenderBox* child, LayoutUnit logicalOffset) |
| { |
| // FIXME: Add page break checking here when we support printing. |
| bool checkColumnBreaks = view()->layoutState()->isPaginatingColumns(); |
| bool checkPageBreaks = !checkColumnBreaks && view()->layoutState()->m_pageLogicalHeight; // FIXME: Once columns can print we have to check this. |
| RenderFlowThread* flowThread = flowThreadContainingBlock(); |
| bool checkRegionBreaks = flowThread && flowThread->isRenderNamedFlowThread(); |
| bool checkBeforeAlways = (checkColumnBreaks && child->style()->columnBreakBefore() == PBALWAYS) || (checkPageBreaks && child->style()->pageBreakBefore() == PBALWAYS) |
| || (checkRegionBreaks && child->style()->regionBreakBefore() == PBALWAYS); |
| if (checkBeforeAlways && inNormalFlow(child) && hasNextPage(logicalOffset, IncludePageBoundary)) { |
| if (checkColumnBreaks) |
| view()->layoutState()->addForcedColumnBreak(child, logicalOffset); |
| if (checkRegionBreaks) { |
| LayoutUnit offsetBreakAdjustment = 0; |
| if (flowThread->addForcedRegionBreak(offsetFromLogicalTopOfFirstPage() + logicalOffset, child, true, &offsetBreakAdjustment)) |
| return logicalOffset + offsetBreakAdjustment; |
| } |
| return nextPageLogicalTop(logicalOffset, IncludePageBoundary); |
| } |
| return logicalOffset; |
| } |
| |
| LayoutUnit RenderBlockFlow::applyAfterBreak(RenderBox* child, LayoutUnit logicalOffset, MarginInfo& marginInfo) |
| { |
| // FIXME: Add page break checking here when we support printing. |
| bool checkColumnBreaks = view()->layoutState()->isPaginatingColumns(); |
| bool checkPageBreaks = !checkColumnBreaks && view()->layoutState()->m_pageLogicalHeight; // FIXME: Once columns can print we have to check this. |
| RenderFlowThread* flowThread = flowThreadContainingBlock(); |
| bool checkRegionBreaks = flowThread && flowThread->isRenderNamedFlowThread(); |
| bool checkAfterAlways = (checkColumnBreaks && child->style()->columnBreakAfter() == PBALWAYS) || (checkPageBreaks && child->style()->pageBreakAfter() == PBALWAYS) |
| || (checkRegionBreaks && child->style()->regionBreakAfter() == PBALWAYS); |
| if (checkAfterAlways && inNormalFlow(child) && hasNextPage(logicalOffset, IncludePageBoundary)) { |
| LayoutUnit marginOffset = marginInfo.canCollapseWithMarginBefore() ? LayoutUnit() : marginInfo.margin(); |
| |
| // So our margin doesn't participate in the next collapsing steps. |
| marginInfo.clearMargin(); |
| |
| if (checkColumnBreaks) |
| view()->layoutState()->addForcedColumnBreak(child, logicalOffset); |
| if (checkRegionBreaks) { |
| LayoutUnit offsetBreakAdjustment = 0; |
| if (flowThread->addForcedRegionBreak(offsetFromLogicalTopOfFirstPage() + logicalOffset + marginOffset, child, false, &offsetBreakAdjustment)) |
| return logicalOffset + marginOffset + offsetBreakAdjustment; |
| } |
| return nextPageLogicalTop(logicalOffset, IncludePageBoundary); |
| } |
| return logicalOffset; |
| } |
| |
| } // namespace WebCore |