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/*
* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
* Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include "RenderView.h"
#include "Document.h"
#include "Element.h"
#include "FloatQuad.h"
#include "FloatingObjects.h"
#include "FlowThreadController.h"
#include "Frame.h"
#include "FrameSelection.h"
#include "FrameView.h"
#include "GraphicsContext.h"
#include "HTMLFrameOwnerElement.h"
#include "HTMLIFrameElement.h"
#include "HitTestResult.h"
#include "ImageQualityController.h"
#include "NodeTraversal.h"
#include "Page.h"
#include "RenderGeometryMap.h"
#include "RenderIterator.h"
#include "RenderLayer.h"
#include "RenderLayerBacking.h"
#include "RenderLayerCompositor.h"
#include "RenderMultiColumnFlowThread.h"
#include "RenderMultiColumnSet.h"
#include "RenderMultiColumnSpannerPlaceholder.h"
#include "RenderNamedFlowThread.h"
#include "RenderSelectionInfo.h"
#include "RenderWidget.h"
#include "Settings.h"
#include "StyleInheritedData.h"
#include "TransformState.h"
#include <wtf/StackStats.h>
namespace WebCore {
struct SelectionIterator {
RenderObject* m_current;
Vector<RenderMultiColumnSpannerPlaceholder*> m_spannerStack;
SelectionIterator(RenderObject* o)
{
m_current = o;
checkForSpanner();
}
void checkForSpanner()
{
if (!m_current || !m_current->isRenderMultiColumnSpannerPlaceholder())
return;
RenderMultiColumnSpannerPlaceholder* placeholder = toRenderMultiColumnSpannerPlaceholder(m_current);
m_spannerStack.append(placeholder);
m_current = placeholder->spanner();
}
RenderObject* current()
{
return m_current;
}
RenderObject* next()
{
RenderObject* currentSpan = m_spannerStack.isEmpty() ? 0 : m_spannerStack.last()->spanner();
m_current = m_current->nextInPreOrder(currentSpan);
checkForSpanner();
if (!m_current && currentSpan) {
RenderObject* placeholder = m_spannerStack.last();
m_spannerStack.removeLast();
m_current = placeholder->nextInPreOrder();
checkForSpanner();
}
return m_current;
}
};
RenderView::RenderView(Document& document, PassRef<RenderStyle> style)
: RenderBlockFlow(document, std::move(style))
, m_frameView(*document.view())
, m_selectionStart(0)
, m_selectionEnd(0)
, m_selectionStartPos(-1)
, m_selectionEndPos(-1)
, m_rendererCount(0)
, m_maximalOutlineSize(0)
, m_lazyRepaintTimer(this, &RenderView::lazyRepaintTimerFired)
, m_pageLogicalHeight(0)
, m_pageLogicalHeightChanged(false)
, m_layoutState(nullptr)
, m_layoutStateDisableCount(0)
, m_renderQuoteHead(0)
, m_renderCounterCount(0)
, m_selectionWasCaret(false)
#if ENABLE(CSS_FILTERS)
, m_hasSoftwareFilters(false)
#endif
#if ENABLE(SERVICE_CONTROLS)
, m_selectionRectGatherer(*this)
#endif
{
setIsRenderView();
// FIXME: We should find a way to enforce this at compile time.
ASSERT(document.view());
// init RenderObject attributes
setInline(false);
m_minPreferredLogicalWidth = 0;
m_maxPreferredLogicalWidth = 0;
setPreferredLogicalWidthsDirty(true, MarkOnlyThis);
setPositionState(AbsolutePosition); // to 0,0 :)
}
RenderView::~RenderView()
{
}
void RenderView::scheduleLazyRepaint(RenderBox& renderer)
{
if (renderer.renderBoxNeedsLazyRepaint())
return;
renderer.setRenderBoxNeedsLazyRepaint(true);
m_renderersNeedingLazyRepaint.add(&renderer);
if (!m_lazyRepaintTimer.isActive())
m_lazyRepaintTimer.startOneShot(0);
}
void RenderView::unscheduleLazyRepaint(RenderBox& renderer)
{
if (!renderer.renderBoxNeedsLazyRepaint())
return;
renderer.setRenderBoxNeedsLazyRepaint(false);
m_renderersNeedingLazyRepaint.remove(&renderer);
if (m_renderersNeedingLazyRepaint.isEmpty())
m_lazyRepaintTimer.stop();
}
void RenderView::lazyRepaintTimerFired(Timer<RenderView>&)
{
bool shouldRepaint = !document().inPageCache();
for (auto& renderer : m_renderersNeedingLazyRepaint) {
if (shouldRepaint)
renderer->repaint();
renderer->setRenderBoxNeedsLazyRepaint(false);
}
m_renderersNeedingLazyRepaint.clear();
}
bool RenderView::hitTest(const HitTestRequest& request, HitTestResult& result)
{
return hitTest(request, result.hitTestLocation(), result);
}
bool RenderView::hitTest(const HitTestRequest& request, const HitTestLocation& location, HitTestResult& result)
{
if (layer()->hitTest(request, location, result))
return true;
// FIXME: Consider if this test should be done unconditionally.
if (request.allowsFrameScrollbars()) {
// ScrollView scrollbars are not the same as RenderLayer scrollbars tested by RenderLayer::hitTestOverflowControls,
// so we need to test ScrollView scrollbars separately here.
Scrollbar* frameScrollbar = frameView().scrollbarAtPoint(location.roundedPoint());
if (frameScrollbar) {
result.setScrollbar(frameScrollbar);
return true;
}
}
return false;
}
void RenderView::computeLogicalHeight(LayoutUnit logicalHeight, LayoutUnit, LogicalExtentComputedValues& computedValues) const
{
computedValues.m_extent = !shouldUsePrintingLayout() ? LayoutUnit(viewLogicalHeight()) : logicalHeight;
}
void RenderView::updateLogicalWidth()
{
if (!shouldUsePrintingLayout())
setLogicalWidth(viewLogicalWidth());
}
LayoutUnit RenderView::availableLogicalHeight(AvailableLogicalHeightType) const
{
// FIXME: Need to patch for new columns?
#if PLATFORM(IOS)
// Workaround for <rdar://problem/7166808>.
if (document().isPluginDocument() && frameView().useFixedLayout())
return frameView().fixedLayoutSize().height();
#endif
return isHorizontalWritingMode() ? frameView().visibleHeight() : frameView().visibleWidth();
}
bool RenderView::isChildAllowed(const RenderObject& child, const RenderStyle&) const
{
return child.isBox();
}
void RenderView::layoutContent(const LayoutState& state)
{
UNUSED_PARAM(state);
ASSERT(needsLayout());
RenderBlockFlow::layout();
if (hasRenderNamedFlowThreads())
flowThreadController().layoutRenderNamedFlowThreads();
#ifndef NDEBUG
checkLayoutState(state);
#endif
}
#ifndef NDEBUG
void RenderView::checkLayoutState(const LayoutState& state)
{
ASSERT(layoutDeltaMatches(LayoutSize()));
ASSERT(!m_layoutStateDisableCount);
ASSERT(m_layoutState.get() == &state);
}
#endif
void RenderView::initializeLayoutState(LayoutState& state)
{
// FIXME: May be better to push a clip and avoid issuing offscreen repaints.
state.m_clipped = false;
state.m_pageLogicalHeight = m_pageLogicalHeight;
state.m_pageLogicalHeightChanged = m_pageLogicalHeightChanged;
state.m_isPaginated = state.m_pageLogicalHeight;
}
// The algorithm below assumes this is a full layout. In case there are previously computed values for regions, supplemental steps are taken
// to ensure the results are the same as those obtained from a full layout (i.e. the auto-height regions from all the flows are marked as needing
// layout).
// 1. The flows are laid out from the outer flow to the inner flow. This successfully computes the outer non-auto-height regions size so the
// inner flows have the necessary information to correctly fragment the content.
// 2. The flows are laid out from the inner flow to the outer flow. After an inner flow is laid out it goes into the constrained layout phase
// and marks the auto-height regions they need layout. This means the outer flows will relayout if they depend on regions with auto-height regions
// belonging to inner flows. This step will correctly set the computedAutoHeight for the auto-height regions. It's possible for non-auto-height
// regions to relayout if they depend on auto-height regions. This will invalidate the inner flow threads and mark them as needing layout.
// 3. The last step is to do one last layout if there are pathological dependencies between non-auto-height regions and auto-height regions
// as detected in the previous step.
void RenderView::layoutContentInAutoLogicalHeightRegions(const LayoutState& state)
{
// We need to invalidate all the flows with auto-height regions if one such flow needs layout.
// If none is found we do a layout a check back again afterwards.
if (!flowThreadController().updateFlowThreadsNeedingLayout()) {
// Do a first layout of the content. In some cases more layouts are not needed (e.g. only flows with non-auto-height regions have changed).
layoutContent(state);
// If we find no named flow needing a two step layout after the first layout, exit early.
// Otherwise, initiate the two step layout algorithm and recompute all the flows.
if (!flowThreadController().updateFlowThreadsNeedingTwoStepLayout())
return;
}
// Layout to recompute all the named flows with auto-height regions.
layoutContent(state);
// Propagate the computed auto-height values upwards.
// Non-auto-height regions may invalidate the flow thread because they depended on auto-height regions, but that's ok.
flowThreadController().updateFlowThreadsIntoConstrainedPhase();
// Do one last layout that should update the auto-height regions found in the main flow
// and solve pathological dependencies between regions (e.g. a non-auto-height region depending
// on an auto-height one).
if (needsLayout())
layoutContent(state);
}
void RenderView::layoutContentToComputeOverflowInRegions(const LayoutState& state)
{
if (!hasRenderNamedFlowThreads())
return;
// First pass through the flow threads and mark the regions as needing a simple layout.
// The regions extract the overflow from the flow thread and pass it to their containg
// block chain.
flowThreadController().updateFlowThreadsIntoOverflowPhase();
if (needsLayout())
layoutContent(state);
// In case scrollbars resized the regions a new pass is necessary to update the flow threads
// and recompute the overflow on regions. This is the final state of the flow threads.
flowThreadController().updateFlowThreadsIntoFinalPhase();
if (needsLayout())
layoutContent(state);
// Finally reset the layout state of the flow threads.
flowThreadController().updateFlowThreadsIntoMeasureContentPhase();
}
void RenderView::layout()
{
StackStats::LayoutCheckPoint layoutCheckPoint;
if (!document().paginated())
setPageLogicalHeight(0);
if (shouldUsePrintingLayout())
m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = logicalWidth();
// Use calcWidth/Height to get the new width/height, since this will take the full page zoom factor into account.
bool relayoutChildren = !shouldUsePrintingLayout() && (width() != viewWidth() || height() != viewHeight());
if (relayoutChildren) {
setChildNeedsLayout(MarkOnlyThis);
for (auto& box : childrenOfType<RenderBox>(*this)) {
if (box.hasRelativeLogicalHeight()
|| box.style().logicalHeight().isPercent()
|| box.style().logicalMinHeight().isPercent()
|| box.style().logicalMaxHeight().isPercent()
|| box.isSVGRoot()
)
box.setChildNeedsLayout(MarkOnlyThis);
}
}
ASSERT(!m_layoutState);
if (!needsLayout())
return;
m_layoutState = std::make_unique<LayoutState>();
initializeLayoutState(*m_layoutState);
m_pageLogicalHeightChanged = false;
if (checkTwoPassLayoutForAutoHeightRegions())
layoutContentInAutoLogicalHeightRegions(*m_layoutState);
else
layoutContent(*m_layoutState);
layoutContentToComputeOverflowInRegions(*m_layoutState);
#ifndef NDEBUG
checkLayoutState(*m_layoutState);
#endif
m_layoutState = nullptr;
clearNeedsLayout();
}
LayoutUnit RenderView::pageOrViewLogicalHeight() const
{
if (document().printing())
return pageLogicalHeight();
if (multiColumnFlowThread() && !style().hasInlineColumnAxis()) {
if (int pageLength = frameView().pagination().pageLength)
return pageLength;
}
return viewLogicalHeight();
}
LayoutUnit RenderView::clientLogicalWidthForFixedPosition() const
{
// FIXME: If the FrameView's fixedVisibleContentRect() is not empty, perhaps it should be consulted here too?
if (frameView().fixedElementsLayoutRelativeToFrame())
return (isHorizontalWritingMode() ? frameView().visibleWidth() : frameView().visibleHeight()) / frameView().frame().frameScaleFactor();
#if PLATFORM(IOS)
if (frameView().useCustomFixedPositionLayoutRect())
return isHorizontalWritingMode() ? frameView().customFixedPositionLayoutRect().width() : frameView().customFixedPositionLayoutRect().height();
#endif
return clientLogicalWidth();
}
LayoutUnit RenderView::clientLogicalHeightForFixedPosition() const
{
// FIXME: If the FrameView's fixedVisibleContentRect() is not empty, perhaps it should be consulted here too?
if (frameView().fixedElementsLayoutRelativeToFrame())
return (isHorizontalWritingMode() ? frameView().visibleHeight() : frameView().visibleWidth()) / frameView().frame().frameScaleFactor();
#if PLATFORM(IOS)
if (frameView().useCustomFixedPositionLayoutRect())
return isHorizontalWritingMode() ? frameView().customFixedPositionLayoutRect().height() : frameView().customFixedPositionLayoutRect().width();
#endif
return clientLogicalHeight();
}
#if PLATFORM(IOS)
static inline LayoutSize fixedPositionOffset(const FrameView& frameView)
{
return frameView.useCustomFixedPositionLayoutRect() ? (frameView.customFixedPositionLayoutRect().location() - LayoutPoint()) : frameView.scrollOffset();
}
#endif
void RenderView::mapLocalToContainer(const RenderLayerModelObject* repaintContainer, TransformState& transformState, MapCoordinatesFlags mode, bool* wasFixed) const
{
// If a container was specified, and was not 0 or the RenderView,
// then we should have found it by now.
ASSERT_ARG(repaintContainer, !repaintContainer || repaintContainer == this);
ASSERT_UNUSED(wasFixed, !wasFixed || *wasFixed == (mode & IsFixed));
if (!repaintContainer && mode & UseTransforms && shouldUseTransformFromContainer(0)) {
TransformationMatrix t;
getTransformFromContainer(0, LayoutSize(), t);
transformState.applyTransform(t);
}
if (mode & IsFixed)
#if PLATFORM(IOS)
transformState.move(fixedPositionOffset(m_frameView));
#else
transformState.move(frameView().scrollOffsetForFixedPosition());
#endif
}
const RenderObject* RenderView::pushMappingToContainer(const RenderLayerModelObject* ancestorToStopAt, RenderGeometryMap& geometryMap) const
{
// If a container was specified, and was not 0 or the RenderView,
// then we should have found it by now.
ASSERT_ARG(ancestorToStopAt, !ancestorToStopAt || ancestorToStopAt == this);
#if PLATFORM(IOS)
LayoutSize scrollOffset = fixedPositionOffset(frameView());
#else
LayoutSize scrollOffset = frameView().scrollOffsetForFixedPosition();
#endif
if (!ancestorToStopAt && shouldUseTransformFromContainer(0)) {
TransformationMatrix t;
getTransformFromContainer(0, LayoutSize(), t);
geometryMap.pushView(this, scrollOffset, &t);
} else
geometryMap.pushView(this, scrollOffset);
return 0;
}
void RenderView::mapAbsoluteToLocalPoint(MapCoordinatesFlags mode, TransformState& transformState) const
{
if (mode & IsFixed)
#if PLATFORM(IOS)
transformState.move(fixedPositionOffset(frameView()));
#else
transformState.move(frameView().scrollOffsetForFixedPosition());
#endif
if (mode & UseTransforms && shouldUseTransformFromContainer(0)) {
TransformationMatrix t;
getTransformFromContainer(0, LayoutSize(), t);
transformState.applyTransform(t);
}
}
bool RenderView::requiresColumns(int) const
{
return frameView().pagination().mode != Pagination::Unpaginated;
}
void RenderView::computeColumnCountAndWidth()
{
int columnWidth = contentLogicalWidth();
if (style().hasInlineColumnAxis()) {
if (int pageLength = frameView().pagination().pageLength)
columnWidth = pageLength;
}
setComputedColumnCountAndWidth(1, columnWidth);
}
void RenderView::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
{
// If we ever require layout but receive a paint anyway, something has gone horribly wrong.
ASSERT(!needsLayout());
// RenderViews should never be called to paint with an offset not on device pixels.
ASSERT(LayoutPoint(IntPoint(paintOffset.x(), paintOffset.y())) == paintOffset);
// This avoids painting garbage between columns if there is a column gap.
if (frameView().pagination().mode != Pagination::Unpaginated && paintInfo.shouldPaintWithinRoot(*this))
paintInfo.context->fillRect(paintInfo.rect, frameView().baseBackgroundColor(), ColorSpaceDeviceRGB);
paintObject(paintInfo, paintOffset);
}
static inline bool isComposited(RenderElement* object)
{
return object->hasLayer() && toRenderLayerModelObject(object)->layer()->isComposited();
}
static inline bool rendererObscuresBackground(RenderElement* rootObject)
{
if (!rootObject)
return false;
const RenderStyle& style = rootObject->style();
if (style.visibility() != VISIBLE
|| style.opacity() != 1
|| style.hasTransform())
return false;
if (isComposited(rootObject))
return false;
if (rootObject->rendererForRootBackground().style().backgroundClip() == TextFillBox)
return false;
return true;
}
void RenderView::paintBoxDecorations(PaintInfo& paintInfo, const LayoutPoint&)
{
if (!paintInfo.shouldPaintWithinRoot(*this))
return;
// Check to see if we are enclosed by a layer that requires complex painting rules. If so, we cannot blit
// when scrolling, and we need to use slow repaints. Examples of layers that require this are transparent layers,
// layers with reflections, or transformed layers.
// FIXME: This needs to be dynamic. We should be able to go back to blitting if we ever stop being inside
// a transform, transparency layer, etc.
Element* elt;
for (elt = document().ownerElement(); elt && elt->renderer(); elt = elt->document().ownerElement()) {
RenderLayer* layer = elt->renderer()->enclosingLayer();
if (layer->cannotBlitToWindow()) {
frameView().setCannotBlitToWindow();
break;
}
if (RenderLayer* compositingLayer = layer->enclosingCompositingLayerForRepaint()) {
if (!compositingLayer->backing()->paintsIntoWindow()) {
frameView().setCannotBlitToWindow();
break;
}
}
}
if (document().ownerElement())
return;
if (paintInfo.skipRootBackground())
return;
bool rootFillsViewport = false;
bool rootObscuresBackground = false;
Element* documentElement = document().documentElement();
if (RenderElement* rootRenderer = documentElement ? documentElement->renderer() : 0) {
// The document element's renderer is currently forced to be a block, but may not always be.
RenderBox* rootBox = rootRenderer->isBox() ? toRenderBox(rootRenderer) : 0;
rootFillsViewport = rootBox && !rootBox->x() && !rootBox->y() && rootBox->width() >= width() && rootBox->height() >= height();
rootObscuresBackground = rendererObscuresBackground(rootRenderer);
}
compositor().setRootExtendedBackgroundColor(frameView().frame().settings().backgroundShouldExtendBeyondPage()
? frameView().documentBackgroundColor() : Color());
Page* page = document().page();
float pageScaleFactor = page ? page->pageScaleFactor() : 1;
// If painting will entirely fill the view, no need to fill the background.
if (rootFillsViewport && rootObscuresBackground && pageScaleFactor >= 1)
return;
// This code typically only executes if the root element's visibility has been set to hidden,
// if there is a transform on the <html>, or if there is a page scale factor less than 1.
// Only fill with the base background color (typically white) if we're the root document,
// since iframes/frames with no background in the child document should show the parent's background.
if (frameView().isTransparent()) // FIXME: This needs to be dynamic. We should be able to go back to blitting if we ever stop being transparent.
frameView().setCannotBlitToWindow(); // The parent must show behind the child.
else {
Color backgroundColor = frameView().baseBackgroundColor();
if (backgroundColor.alpha()) {
CompositeOperator previousOperator = paintInfo.context->compositeOperation();
paintInfo.context->setCompositeOperation(CompositeCopy);
paintInfo.context->fillRect(paintInfo.rect, backgroundColor, style().colorSpace());
paintInfo.context->setCompositeOperation(previousOperator);
} else
paintInfo.context->clearRect(paintInfo.rect);
}
}
bool RenderView::shouldRepaint(const LayoutRect& rect) const
{
return !printing() && !rect.isEmpty();
}
void RenderView::repaintRootContents()
{
if (layer()->isComposited()) {
layer()->setBackingNeedsRepaint(GraphicsLayer::DoNotClipToLayer);
return;
}
repaint();
}
void RenderView::repaintViewRectangle(const LayoutRect& repaintRect) const
{
if (!shouldRepaint(repaintRect))
return;
if (auto ownerElement = document().ownerElement()) {
RenderBox* ownerBox = ownerElement->renderBox();
if (!ownerBox)
return;
LayoutRect viewRect = this->viewRect();
#if PLATFORM(IOS)
// Don't clip using the visible rect since clipping is handled at a higher level on iPhone.
LayoutRect adjustedRect = repaintRect;
#else
LayoutRect adjustedRect = intersection(repaintRect, viewRect);
#endif
adjustedRect.moveBy(-viewRect.location());
adjustedRect.moveBy(ownerBox->contentBoxRect().location());
ownerBox->repaintRectangle(adjustedRect);
return;
}
frameView().addTrackedRepaintRect(pixelSnappedForPainting(repaintRect, document().deviceScaleFactor()));
// FIXME: convert all repaint rect dependencies to FloatRect.
IntRect enclosingRect = enclosingIntRect(repaintRect);
if (!m_accumulatedRepaintRegion) {
frameView().repaintContentRectangle(enclosingRect);
return;
}
m_accumulatedRepaintRegion->unite(enclosingRect);
// Region will get slow if it gets too complex. Merge all rects so far to bounds if this happens.
// FIXME: Maybe there should be a region type that does this automatically.
static const unsigned maximumRepaintRegionGridSize = 16 * 16;
if (m_accumulatedRepaintRegion->gridSize() > maximumRepaintRegionGridSize)
m_accumulatedRepaintRegion = std::make_unique<Region>(m_accumulatedRepaintRegion->bounds());
}
void RenderView::flushAccumulatedRepaintRegion() const
{
ASSERT(!document().ownerElement());
ASSERT(m_accumulatedRepaintRegion);
auto repaintRects = m_accumulatedRepaintRegion->rects();
for (auto& rect : repaintRects)
frameView().repaintContentRectangle(rect);
m_accumulatedRepaintRegion = nullptr;
}
void RenderView::repaintViewAndCompositedLayers()
{
repaintRootContents();
RenderLayerCompositor& compositor = this->compositor();
if (compositor.inCompositingMode())
compositor.repaintCompositedLayers();
}
LayoutRect RenderView::visualOverflowRect() const
{
if (frameView().paintsEntireContents())
return layoutOverflowRect();
return RenderBlockFlow::visualOverflowRect();
}
void RenderView::computeRectForRepaint(const RenderLayerModelObject* repaintContainer, LayoutRect& rect, bool fixed) const
{
// If a container was specified, and was not 0 or the RenderView,
// then we should have found it by now.
ASSERT_ARG(repaintContainer, !repaintContainer || repaintContainer == this);
if (printing())
return;
if (style().isFlippedBlocksWritingMode()) {
// We have to flip by hand since the view's logical height has not been determined. We
// can use the viewport width and height.
if (style().isHorizontalWritingMode())
rect.setY(viewHeight() - rect.maxY());
else
rect.setX(viewWidth() - rect.maxX());
}
if (fixed) {
#if PLATFORM(IOS)
rect.move(fixedPositionOffset(frameView()));
#else
rect.move(frameView().scrollOffsetForFixedPosition());
#endif
}
// Apply our transform if we have one (because of full page zooming).
if (!repaintContainer && layer() && layer()->transform())
rect = LayoutRect(layer()->transform()->mapRect(pixelSnappedForPainting(rect, document().deviceScaleFactor())));
}
void RenderView::absoluteRects(Vector<IntRect>& rects, const LayoutPoint& accumulatedOffset) const
{
rects.append(pixelSnappedIntRect(accumulatedOffset, layer()->size()));
}
void RenderView::absoluteQuads(Vector<FloatQuad>& quads, bool* wasFixed) const
{
if (wasFixed)
*wasFixed = false;
quads.append(FloatRect(FloatPoint(), layer()->size()));
}
static RenderObject* rendererAfterPosition(RenderObject* object, unsigned offset)
{
if (!object)
return 0;
RenderObject* child = object->childAt(offset);
return child ? child : object->nextInPreOrderAfterChildren();
}
IntRect RenderView::selectionBounds(bool clipToVisibleContent) const
{
LayoutRect selRect = subtreeSelectionBounds(*this, clipToVisibleContent);
if (hasRenderNamedFlowThreads()) {
for (auto* namedFlowThread : *m_flowThreadController->renderNamedFlowThreadList()) {
LayoutRect currRect = subtreeSelectionBounds(*namedFlowThread, clipToVisibleContent);
selRect.unite(currRect);
}
}
return pixelSnappedIntRect(selRect);
}
LayoutRect RenderView::subtreeSelectionBounds(const SelectionSubtreeRoot& root, bool clipToVisibleContent) const
{
typedef HashMap<RenderObject*, std::unique_ptr<RenderSelectionInfo>> SelectionMap;
SelectionMap selectedObjects;
RenderObject* os = root.selectionStart();
RenderObject* stop = rendererAfterPosition(root.selectionEnd(), root.selectionEndPos());
SelectionIterator selectionIterator(os);
while (os && os != stop) {
if ((os->canBeSelectionLeaf() || os == root.selectionStart() || os == root.selectionEnd()) && os->selectionState() != SelectionNone) {
// Blocks are responsible for painting line gaps and margin gaps. They must be examined as well.
selectedObjects.set(os, std::make_unique<RenderSelectionInfo>(os, clipToVisibleContent));
RenderBlock* cb = os->containingBlock();
while (cb && !cb->isRenderView()) {
std::unique_ptr<RenderSelectionInfo>& blockInfo = selectedObjects.add(cb, nullptr).iterator->value;
if (blockInfo)
break;
blockInfo = std::make_unique<RenderSelectionInfo>(cb, clipToVisibleContent);
cb = cb->containingBlock();
}
}
os = selectionIterator.next();
}
// Now create a single bounding box rect that encloses the whole selection.
LayoutRect selRect;
SelectionMap::iterator end = selectedObjects.end();
for (SelectionMap::iterator i = selectedObjects.begin(); i != end; ++i) {
RenderSelectionInfo* info = i->value.get();
// RenderSelectionInfo::rect() is in the coordinates of the repaintContainer, so map to page coordinates.
LayoutRect currRect = info->rect();
if (RenderLayerModelObject* repaintContainer = info->repaintContainer()) {
FloatQuad absQuad = repaintContainer->localToAbsoluteQuad(FloatRect(currRect));
currRect = absQuad.enclosingBoundingBox();
}
selRect.unite(currRect);
}
return selRect;
}
void RenderView::repaintSelection() const
{
repaintSubtreeSelection(*this);
if (hasRenderNamedFlowThreads()) {
for (auto* namedFlowThread : *m_flowThreadController->renderNamedFlowThreadList())
repaintSubtreeSelection(*namedFlowThread);
}
}
void RenderView::repaintSubtreeSelection(const SelectionSubtreeRoot& root) const
{
HashSet<RenderBlock*> processedBlocks;
RenderObject* end = rendererAfterPosition(root.selectionEnd(), root.selectionEndPos());
SelectionIterator selectionIterator(root.selectionStart());
for (RenderObject* o = selectionIterator.current(); o && o != end; o = selectionIterator.next()) {
if (!o->canBeSelectionLeaf() && o != root.selectionStart() && o != root.selectionEnd())
continue;
if (o->selectionState() == SelectionNone)
continue;
RenderSelectionInfo(o, true).repaint();
// Blocks are responsible for painting line gaps and margin gaps. They must be examined as well.
for (RenderBlock* block = o->containingBlock(); block && !block->isRenderView(); block = block->containingBlock()) {
if (!processedBlocks.add(block).isNewEntry)
break;
RenderSelectionInfo(block, true).repaint();
}
}
}
// Compositing layer dimensions take outline size into account, so we have to recompute layer
// bounds when it changes.
// FIXME: This is ugly; it would be nice to have a better way to do this.
void RenderView::setMaximalOutlineSize(int o)
{
if (o != m_maximalOutlineSize) {
m_maximalOutlineSize = o;
// maximalOutlineSize affects compositing layer dimensions.
compositor().setCompositingLayersNeedRebuild(); // FIXME: this really just needs to be a geometry update.
}
}
void RenderView::setSelection(RenderObject* start, int startPos, RenderObject* end, int endPos, SelectionRepaintMode blockRepaintMode)
{
#if ENABLE(SERVICE_CONTROLS)
// Clear the current rects and create a notifier for the new rects we are about to gather.
// The Notifier updates the Editor when it goes out of scope and is destroyed.
std::unique_ptr<SelectionRectGatherer::Notifier> rectNotifier = m_selectionRectGatherer.clearAndCreateNotifier();
#endif // ENABLE(SERVICE_CONTROLS)
// Make sure both our start and end objects are defined.
// Check www.msnbc.com and try clicking around to find the case where this happened.
if ((start && !end) || (end && !start))
return;
bool caretChanged = m_selectionWasCaret != view().frame().selection().isCaret();
m_selectionWasCaret = view().frame().selection().isCaret();
// Just return if the selection hasn't changed.
if (m_selectionStart == start && m_selectionStartPos == startPos &&
m_selectionEnd == end && m_selectionEndPos == endPos && !caretChanged)
return;
// Set global positions for new selection.
m_selectionStart = start;
m_selectionStartPos = startPos;
m_selectionEnd = end;
m_selectionEndPos = endPos;
// If there is no RenderNamedFlowThreads we follow the regular selection.
if (!hasRenderNamedFlowThreads()) {
setSubtreeSelection(*this, start, startPos, end, endPos, blockRepaintMode);
return;
}
splitSelectionBetweenSubtrees(start, startPos, end, endPos, blockRepaintMode);
}
void RenderView::splitSelectionBetweenSubtrees(RenderObject* start, int startPos, RenderObject* end, int endPos, SelectionRepaintMode blockRepaintMode)
{
// Compute the visible selection end points for each of the subtrees.
typedef HashMap<SelectionSubtreeRoot*, SelectionSubtreeRoot> RenderSubtreesMap;
RenderSubtreesMap renderSubtreesMap;
SelectionSubtreeRoot initialSelection;
renderSubtreesMap.set(this, initialSelection);
for (auto* namedFlowThread : *flowThreadController().renderNamedFlowThreadList())
renderSubtreesMap.set(namedFlowThread, initialSelection);
if (start && end) {
Node* startNode = start->node();
Node* endNode = end->node();
Node* stopNode = NodeTraversal::nextSkippingChildren(endNode);
for (Node* node = startNode; node != stopNode; node = NodeTraversal::next(node)) {
RenderObject* renderer = node->renderer();
if (!renderer)
continue;
SelectionSubtreeRoot& root = renderer->selectionRoot();
SelectionSubtreeRoot selectionData = renderSubtreesMap.get(&root);
if (selectionData.selectionClear()) {
selectionData.setSelectionStart(node->renderer());
selectionData.setSelectionStartPos(node == startNode ? startPos : 0);
}
selectionData.setSelectionEnd(node->renderer());
if (node == endNode)
selectionData.setSelectionEndPos(endPos);
else
selectionData.setSelectionEndPos(node->offsetInCharacters() ? node->maxCharacterOffset() : node->childNodeCount());
renderSubtreesMap.set(&root, selectionData);
}
}
for (RenderSubtreesMap::iterator i = renderSubtreesMap.begin(); i != renderSubtreesMap.end(); ++i) {
SelectionSubtreeRoot subtreeSelectionData = i->value;
subtreeSelectionData.adjustForVisibleSelection(document());
setSubtreeSelection(*i->key, subtreeSelectionData.selectionStart(), subtreeSelectionData.selectionStartPos(),
subtreeSelectionData.selectionEnd(), subtreeSelectionData.selectionEndPos(), blockRepaintMode);
}
}
void RenderView::setSubtreeSelection(SelectionSubtreeRoot& root, RenderObject* start, int startPos, RenderObject* end, int endPos, SelectionRepaintMode blockRepaintMode)
{
// Record the old selected objects. These will be used later
// when we compare against the new selected objects.
int oldStartPos = root.selectionStartPos();
int oldEndPos = root.selectionEndPos();
// Objects each have a single selection rect to examine.
typedef HashMap<RenderObject*, std::unique_ptr<RenderSelectionInfo>> SelectedObjectMap;
SelectedObjectMap oldSelectedObjects;
SelectedObjectMap newSelectedObjects;
// Blocks contain selected objects and fill gaps between them, either on the left, right, or in between lines and blocks.
// In order to get the repaint rect right, we have to examine left, middle, and right rects individually, since otherwise
// the union of those rects might remain the same even when changes have occurred.
typedef HashMap<RenderBlock*, std::unique_ptr<RenderBlockSelectionInfo>> SelectedBlockMap;
SelectedBlockMap oldSelectedBlocks;
SelectedBlockMap newSelectedBlocks;
RenderObject* os = root.selectionStart();
RenderObject* stop = rendererAfterPosition(root.selectionEnd(), root.selectionEndPos());
SelectionIterator selectionIterator(os);
while (os && os != stop) {
if ((os->canBeSelectionLeaf() || os == root.selectionStart() || os == root.selectionEnd())
&& os->selectionState() != SelectionNone) {
// Blocks are responsible for painting line gaps and margin gaps. They must be examined as well.
oldSelectedObjects.set(os, std::make_unique<RenderSelectionInfo>(os, true));
if (blockRepaintMode == RepaintNewXOROld) {
RenderBlock* cb = os->containingBlock();
while (cb && !cb->isRenderView()) {
std::unique_ptr<RenderBlockSelectionInfo>& blockInfo = oldSelectedBlocks.add(cb, nullptr).iterator->value;
if (blockInfo)
break;
blockInfo = std::make_unique<RenderBlockSelectionInfo>(cb);
cb = cb->containingBlock();
}
}
}
os = selectionIterator.next();
}
// Now clear the selection.
SelectedObjectMap::iterator oldObjectsEnd = oldSelectedObjects.end();
for (SelectedObjectMap::iterator i = oldSelectedObjects.begin(); i != oldObjectsEnd; ++i)
i->key->setSelectionStateIfNeeded(SelectionNone);
// set selection start and end
root.setSelectionStart(start);
root.setSelectionStartPos(startPos);
root.setSelectionEnd(end);
root.setSelectionEndPos(endPos);
// Update the selection status of all objects between selectionStart and selectionEnd
if (start && start == end)
start->setSelectionStateIfNeeded(SelectionBoth);
else {
if (start)
start->setSelectionStateIfNeeded(SelectionStart);
if (end)
end->setSelectionStateIfNeeded(SelectionEnd);
}
RenderObject* o = start;
stop = rendererAfterPosition(end, endPos);
selectionIterator = SelectionIterator(o);
while (o && o != stop) {
if (o != start && o != end && o->canBeSelectionLeaf())
o->setSelectionStateIfNeeded(SelectionInside);
o = selectionIterator.next();
}
if (blockRepaintMode != RepaintNothing)
layer()->clearBlockSelectionGapsBounds();
// Now that the selection state has been updated for the new objects, walk them again and
// put them in the new objects list.
o = start;
selectionIterator = SelectionIterator(o);
while (o && o != stop) {
if ((o->canBeSelectionLeaf() || o == start || o == end) && o->selectionState() != SelectionNone) {
std::unique_ptr<RenderSelectionInfo> selectionInfo = std::make_unique<RenderSelectionInfo>(o, true);
#if ENABLE(SERVICE_CONTROLS)
m_selectionRectGatherer.addRect(selectionInfo->rect());
#endif
newSelectedObjects.set(o, std::move(selectionInfo));
RenderBlock* cb = o->containingBlock();
while (cb && !cb->isRenderView()) {
std::unique_ptr<RenderBlockSelectionInfo>& blockInfo = newSelectedBlocks.add(cb, nullptr).iterator->value;
if (blockInfo)
break;
blockInfo = std::make_unique<RenderBlockSelectionInfo>(cb);
cb = cb->containingBlock();
#if ENABLE(SERVICE_CONTROLS)
m_selectionRectGatherer.addRects(blockInfo->rects());
#endif
}
}
o = selectionIterator.next();
}
if (blockRepaintMode == RepaintNothing)
return;
// Have any of the old selected objects changed compared to the new selection?
for (SelectedObjectMap::iterator i = oldSelectedObjects.begin(); i != oldObjectsEnd; ++i) {
RenderObject* obj = i->key;
RenderSelectionInfo* newInfo = newSelectedObjects.get(obj);
RenderSelectionInfo* oldInfo = i->value.get();
if (!newInfo || oldInfo->rect() != newInfo->rect() || oldInfo->state() != newInfo->state()
|| (root.selectionStart() == obj && oldStartPos != root.selectionStartPos())
|| (root.selectionEnd() == obj && oldEndPos != root.selectionEndPos())) {
oldInfo->repaint();
if (newInfo) {
newInfo->repaint();
newSelectedObjects.remove(obj);
}
}
}
// Any new objects that remain were not found in the old objects dict, and so they need to be updated.
SelectedObjectMap::iterator newObjectsEnd = newSelectedObjects.end();
for (SelectedObjectMap::iterator i = newSelectedObjects.begin(); i != newObjectsEnd; ++i)
i->value->repaint();
// Have any of the old blocks changed?
SelectedBlockMap::iterator oldBlocksEnd = oldSelectedBlocks.end();
for (SelectedBlockMap::iterator i = oldSelectedBlocks.begin(); i != oldBlocksEnd; ++i) {
RenderBlock* block = i->key;
RenderBlockSelectionInfo* newInfo = newSelectedBlocks.get(block);
RenderBlockSelectionInfo* oldInfo = i->value.get();
if (!newInfo || oldInfo->rects() != newInfo->rects() || oldInfo->state() != newInfo->state()) {
oldInfo->repaint();
if (newInfo) {
newInfo->repaint();
newSelectedBlocks.remove(block);
}
}
}
// Any new blocks that remain were not found in the old blocks dict, and so they need to be updated.
SelectedBlockMap::iterator newBlocksEnd = newSelectedBlocks.end();
for (SelectedBlockMap::iterator i = newSelectedBlocks.begin(); i != newBlocksEnd; ++i)
i->value->repaint();
}
void RenderView::getSelection(RenderObject*& startRenderer, int& startOffset, RenderObject*& endRenderer, int& endOffset) const
{
startRenderer = m_selectionStart;
startOffset = m_selectionStartPos;
endRenderer = m_selectionEnd;
endOffset = m_selectionEndPos;
}
void RenderView::clearSelection()
{
layer()->repaintBlockSelectionGaps();
setSelection(0, -1, 0, -1, RepaintNewMinusOld);
}
bool RenderView::printing() const
{
return document().printing();
}
bool RenderView::shouldUsePrintingLayout() const
{
if (!printing())
return false;
return frameView().frame().shouldUsePrintingLayout();
}
LayoutRect RenderView::viewRect() const
{
if (shouldUsePrintingLayout())
return LayoutRect(LayoutPoint(), size());
return frameView().visibleContentRect(ScrollableArea::LegacyIOSDocumentVisibleRect);
}
IntRect RenderView::unscaledDocumentRect() const
{
LayoutRect overflowRect(layoutOverflowRect());
flipForWritingMode(overflowRect);
return pixelSnappedIntRect(overflowRect);
}
bool RenderView::rootBackgroundIsEntirelyFixed() const
{
RenderElement* rootObject = document().documentElement() ? document().documentElement()->renderer() : 0;
if (!rootObject)
return false;
return rootObject->rendererForRootBackground().hasEntirelyFixedBackground();
}
LayoutRect RenderView::unextendedBackgroundRect(RenderBox*) const
{
// FIXME: What is this? Need to patch for new columns?
return unscaledDocumentRect();
}
LayoutRect RenderView::backgroundRect(RenderBox* backgroundRenderer) const
{
// FIXME: New columns care about this?
if (frameView().hasExtendedBackgroundRectForPainting())
return frameView().extendedBackgroundRectForPainting();
return unextendedBackgroundRect(backgroundRenderer);
}
IntRect RenderView::documentRect() const
{
FloatRect overflowRect(unscaledDocumentRect());
if (hasTransform())
overflowRect = layer()->currentTransform().mapRect(overflowRect);
return IntRect(overflowRect);
}
int RenderView::viewHeight() const
{
int height = 0;
if (!shouldUsePrintingLayout()) {
height = frameView().layoutHeight();
height = frameView().useFixedLayout() ? ceilf(style().effectiveZoom() * float(height)) : height;
}
return height;
}
int RenderView::viewWidth() const
{
int width = 0;
if (!shouldUsePrintingLayout()) {
width = frameView().layoutWidth();
width = frameView().useFixedLayout() ? ceilf(style().effectiveZoom() * float(width)) : width;
}
return width;
}
int RenderView::viewLogicalHeight() const
{
int height = style().isHorizontalWritingMode() ? viewHeight() : viewWidth();
return height;
}
float RenderView::zoomFactor() const
{
return frameView().frame().pageZoomFactor();
}
void RenderView::pushLayoutState(RenderObject& root)
{
ASSERT(m_layoutStateDisableCount == 0);
ASSERT(m_layoutState == 0);
m_layoutState = std::make_unique<LayoutState>(root);
pushLayoutStateForCurrentFlowThread(root);
}
bool RenderView::shouldDisableLayoutStateForSubtree(RenderObject* renderer) const
{
RenderObject* o = renderer;
while (o) {
if (o->hasTransform() || o->hasReflection())
return true;
o = o->container();
}
return false;
}
IntSize RenderView::viewportSizeForCSSViewportUnits() const
{
return frameView().viewportSizeForCSSViewportUnits();
}
void RenderView::updateHitTestResult(HitTestResult& result, const LayoutPoint& point)
{
if (result.innerNode())
return;
Node* node = document().documentElement();
if (node) {
result.setInnerNode(node);
if (!result.innerNonSharedNode())
result.setInnerNonSharedNode(node);
LayoutPoint adjustedPoint = point;
offsetForContents(adjustedPoint);
result.setLocalPoint(adjustedPoint);
}
}
// FIXME: This function is obsolete and only used by embedded WebViews inside AppKit NSViews.
// Do not add callers of this function!
// The idea here is to take into account what object is moving the pagination point, and
// thus choose the best place to chop it.
void RenderView::setBestTruncatedAt(int y, RenderBoxModelObject* forRenderer, bool forcedBreak)
{
// Nobody else can set a page break once we have a forced break.
if (m_legacyPrinting.m_forcedPageBreak)
return;
// Forced breaks always win over unforced breaks.
if (forcedBreak) {
m_legacyPrinting.m_forcedPageBreak = true;
m_legacyPrinting.m_bestTruncatedAt = y;
return;
}
// Prefer the widest object that tries to move the pagination point
IntRect boundingBox = forRenderer->borderBoundingBox();
if (boundingBox.width() > m_legacyPrinting.m_truncatorWidth) {
m_legacyPrinting.m_truncatorWidth = boundingBox.width();
m_legacyPrinting.m_bestTruncatedAt = y;
}
}
bool RenderView::usesCompositing() const
{
return m_compositor && m_compositor->inCompositingMode();
}
RenderLayerCompositor& RenderView::compositor()
{
if (!m_compositor)
m_compositor = std::make_unique<RenderLayerCompositor>(*this);
return *m_compositor;
}
void RenderView::setIsInWindow(bool isInWindow)
{
if (m_compositor)
m_compositor->setIsInWindow(isInWindow);
}
void RenderView::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
{
RenderBlockFlow::styleDidChange(diff, oldStyle);
if (hasRenderNamedFlowThreads())
flowThreadController().styleDidChange();
frameView().styleDidChange();
}
bool RenderView::hasRenderNamedFlowThreads() const
{
return m_flowThreadController && m_flowThreadController->hasRenderNamedFlowThreads();
}
bool RenderView::checkTwoPassLayoutForAutoHeightRegions() const
{
return hasRenderNamedFlowThreads() && m_flowThreadController->hasFlowThreadsWithAutoLogicalHeightRegions();
}
FlowThreadController& RenderView::flowThreadController()
{
if (!m_flowThreadController)
m_flowThreadController = std::make_unique<FlowThreadController>(this);
return *m_flowThreadController;
}
void RenderView::pushLayoutStateForCurrentFlowThread(const RenderObject& object)
{
if (!m_flowThreadController)
return;
RenderFlowThread* currentFlowThread = m_flowThreadController->currentRenderFlowThread();
if (!currentFlowThread)
return;
currentFlowThread->pushFlowThreadLayoutState(object);
}
void RenderView::popLayoutStateForCurrentFlowThread()
{
if (!m_flowThreadController)
return;
RenderFlowThread* currentFlowThread = m_flowThreadController->currentRenderFlowThread();
if (!currentFlowThread)
return;
currentFlowThread->popFlowThreadLayoutState();
}
IntervalArena* RenderView::intervalArena()
{
if (!m_intervalArena)
m_intervalArena = IntervalArena::create();
return m_intervalArena.get();
}
ImageQualityController& RenderView::imageQualityController()
{
if (!m_imageQualityController)
m_imageQualityController = std::make_unique<ImageQualityController>(*this);
return *m_imageQualityController;
}
void RenderView::addRendererWithPausedImageAnimations(RenderElement& renderer)
{
if (renderer.hasPausedImageAnimations()) {
ASSERT(m_renderersWithPausedImageAnimation.contains(&renderer));
return;
}
renderer.setHasPausedImageAnimations(true);
m_renderersWithPausedImageAnimation.add(&renderer);
}
void RenderView::removeRendererWithPausedImageAnimations(RenderElement& renderer)
{
ASSERT(renderer.hasPausedImageAnimations());
ASSERT(m_renderersWithPausedImageAnimation.contains(&renderer));
renderer.setHasPausedImageAnimations(false);
m_renderersWithPausedImageAnimation.remove(&renderer);
}
void RenderView::resumePausedImageAnimationsIfNeeded()
{
auto visibleRect = frameView().visibleContentRect();
Vector<RenderElement*, 10> toRemove;
for (auto* renderer : m_renderersWithPausedImageAnimation) {
if (renderer->repaintForPausedImageAnimationsIfNeeded(visibleRect))
toRemove.append(renderer);
}
for (auto& renderer : toRemove)
removeRendererWithPausedImageAnimations(*renderer);
}
RenderView::RepaintRegionAccumulator::RepaintRegionAccumulator(RenderView* view)
: m_rootView(view ? view->document().topDocument().renderView() : nullptr)
{
if (!m_rootView)
return;
m_wasAccumulatingRepaintRegion = !!m_rootView->m_accumulatedRepaintRegion;
if (!m_wasAccumulatingRepaintRegion)
m_rootView->m_accumulatedRepaintRegion = std::make_unique<Region>();
}
RenderView::RepaintRegionAccumulator::~RepaintRegionAccumulator()
{
if (!m_rootView)
return;
if (m_wasAccumulatingRepaintRegion)
return;
m_rootView->flushAccumulatedRepaintRegion();
}
unsigned RenderView::pageNumberForBlockProgressionOffset(int offset) const
{
int columnNumber = 0;
const Pagination& pagination = frameView().frame().page()->pagination();
if (pagination.mode == Pagination::Unpaginated)
return columnNumber;
bool progressionIsInline = false;
bool progressionIsReversed = false;
if (multiColumnFlowThread()) {
progressionIsInline = multiColumnFlowThread()->progressionIsInline();
progressionIsReversed = multiColumnFlowThread()->progressionIsReversed();
} else
return columnNumber;
if (!progressionIsInline) {
if (!progressionIsReversed)
columnNumber = (pagination.pageLength + pagination.gap - offset) / (pagination.pageLength + pagination.gap);
else
columnNumber = offset / (pagination.pageLength + pagination.gap);
}
return columnNumber;
}
unsigned RenderView::pageCount() const
{
const Pagination& pagination = frameView().frame().page()->pagination();
if (pagination.mode == Pagination::Unpaginated)
return 0;
if (multiColumnFlowThread() && multiColumnFlowThread()->firstMultiColumnSet())
return multiColumnFlowThread()->firstMultiColumnSet()->columnCount();
return 0;
}
} // namespace WebCore