FCL/sf/mw/qtwebkit: comparison WebCore/rendering/RenderObject.cpp

equal deleted inserted replaced

--1:000000000000
+:4f2f89ce4247
+/*
+* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
+*           (C) 1999 Antti Koivisto (koivisto@kde.org)
+*           (C) 2000 Dirk Mueller (mueller@kde.org)
+*           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
+* Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
+* Copyright (C) 2009 Google Inc. All rights reserved.
+* Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
+*
+* 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 "RenderObject.h"
+#include "AXObjectCache.h"
+#include "Chrome.h"
+#include "CSSStyleSelector.h"
+#include "DashArray.h"
+#include "FloatQuad.h"
+#include "Frame.h"
+#include "FrameView.h"
+#include "GraphicsContext.h"
+#include "HTMLNames.h"
+#include "HitTestResult.h"
+#include "Page.h"
+#include "RenderArena.h"
+#include "RenderCounter.h"
+#include "RenderFlexibleBox.h"
+#include "RenderImageGeneratedContent.h"
+#include "RenderInline.h"
+#include "RenderLayer.h"
+#include "RenderListItem.h"
+#include "RenderRuby.h"
+#include "RenderRubyText.h"
+#include "RenderTableCell.h"
+#include "RenderTableCol.h"
+#include "RenderTableRow.h"
+#include "RenderTheme.h"
+#include "RenderView.h"
+#include "TransformState.h"
+#include "htmlediting.h"
+#include <algorithm>
+#include <stdio.h>
+#include <wtf/RefCountedLeakCounter.h>
+#include <wtf/UnusedParam.h>
+#if USE(ACCELERATED_COMPOSITING)
+#include "RenderLayerCompositor.h"
+#endif
+#if ENABLE(WML)
+#include "WMLNames.h"
+#endif
+#if ENABLE(SVG)
+#include "RenderSVGResourceContainer.h"
+#include "SVGRenderSupport.h"
+#endif
+using namespace std;
+namespace WebCore {
+using namespace HTMLNames;
+#ifndef NDEBUG
+static void* baseOfRenderObjectBeingDeleted;
+#endif
+bool RenderObject::s_affectsParentBlock = false;
+void* RenderObject::operator new(size_t sz, RenderArena* renderArena) throw()
+{
+return renderArena->allocate(sz);
+}
+void RenderObject::operator delete(void* ptr, size_t sz)
+{
+ASSERT(baseOfRenderObjectBeingDeleted == ptr);
+// Stash size where destroy can find it.
+*(size_t *)ptr = sz;
+}
+RenderObject* RenderObject::createObject(Node* node, RenderStyle* style)
+{
+Document* doc = node->document();
+RenderArena* arena = doc->renderArena();
+// Minimal support for content properties replacing an entire element.
+// Works only if we have exactly one piece of content and it's a URL.
+// Otherwise acts as if we didn't support this feature.
+const ContentData* contentData = style->contentData();
+if (contentData && !contentData->next() && contentData->isImage() && doc != node) {
+RenderImageGeneratedContent* image = new (arena) RenderImageGeneratedContent(node);
+image->setStyle(style);
+if (StyleImage* styleImage = contentData->image())
+image->setStyleImage(styleImage);
+return image;
+}
+#if ENABLE(RUBY)
+if (node->hasTagName(rubyTag)) {
+if (style->display() == INLINE)
+return new (arena) RenderRubyAsInline(node);
+else if (style->display() == BLOCK)
+return new (arena) RenderRubyAsBlock(node);
+}
+// treat <rt> as ruby text ONLY if it still has its default treatment of block
+if (node->hasTagName(rtTag) && style->display() == BLOCK)
+return new (arena) RenderRubyText(node);
+#endif
+switch (style->display()) {
+case NONE:
+return 0;
+case INLINE:
+return new (arena) RenderInline(node);
+case BLOCK:
+case INLINE_BLOCK:
+case RUN_IN:
+case COMPACT:
+return new (arena) RenderBlock(node);
+case LIST_ITEM:
+return new (arena) RenderListItem(node);
+case TABLE:
+case INLINE_TABLE:
+return new (arena) RenderTable(node);
+case TABLE_ROW_GROUP:
+case TABLE_HEADER_GROUP:
+case TABLE_FOOTER_GROUP:
+return new (arena) RenderTableSection(node);
+case TABLE_ROW:
+return new (arena) RenderTableRow(node);
+case TABLE_COLUMN_GROUP:
+case TABLE_COLUMN:
+return new (arena) RenderTableCol(node);
+case TABLE_CELL:
+return new (arena) RenderTableCell(node);
+case TABLE_CAPTION:
+#if ENABLE(WCSS)
+// As per the section 17.1 of the spec WAP-239-WCSS-20011026-a.pdf,
+// the marquee box inherits and extends the characteristics of the
+// principal block box ([CSS2] section 9.2.1).
+case WAP_MARQUEE:
+#endif
+return new (arena) RenderBlock(node);
+case BOX:
+case INLINE_BOX:
+return new (arena) RenderFlexibleBox(node);
+}
+return 0;
+}
+#ifndef NDEBUG
+static WTF::RefCountedLeakCounter renderObjectCounter("RenderObject");
+#endif
+RenderObject::RenderObject(Node* node)
+: CachedResourceClient()
+, m_style(0)
+, m_node(node)
+, m_parent(0)
+, m_previous(0)
+, m_next(0)
+#ifndef NDEBUG
+, m_hasAXObject(false)
+, m_setNeedsLayoutForbidden(false)
+#endif
+, m_needsLayout(false)
+, m_needsPositionedMovementLayout(false)
+, m_normalChildNeedsLayout(false)
+, m_posChildNeedsLayout(false)
+, m_prefWidthsDirty(false)
+, m_floating(false)
+, m_positioned(false)
+, m_relPositioned(false)
+, m_paintBackground(false)
+, m_isAnonymous(node == node->document())
+, m_isText(false)
+, m_isBox(false)
+, m_inline(true)
+, m_replaced(false)
+, m_isDragging(false)
+, m_hasLayer(false)
+, m_hasOverflowClip(false)
+, m_hasTransform(false)
+, m_hasReflection(false)
+, m_hasOverrideSize(false)
+, m_hasCounterNodeMap(false)
+, m_everHadLayout(false)
+, m_childrenInline(false)
+, m_topMarginQuirk(false)
+, m_bottomMarginQuirk(false)
+, m_hasMarkupTruncation(false)
+, m_selectionState(SelectionNone)
+, m_hasColumns(false)
+, m_cellWidthChanged(false)
+{
+#ifndef NDEBUG
+renderObjectCounter.increment();
+#endif
+ASSERT(node);
+}
+RenderObject::~RenderObject()
+{
+ASSERT(!node() || documentBeingDestroyed() || !frame()->view() || frame()->view()->layoutRoot() != this);
+#ifndef NDEBUG
+ASSERT(!m_hasAXObject);
+renderObjectCounter.decrement();
+#endif
+}
+RenderTheme* RenderObject::theme() const
+{
+ASSERT(document()->page());
+return document()->page()->theme();
+}
+bool RenderObject::isDescendantOf(const RenderObject* obj) const
+{
+for (const RenderObject* r = this; r; r = r->m_parent) {
+if (r == obj)
+return true;
+}
+return false;
+}
+bool RenderObject::isBody() const
+{
+return node() && node()->hasTagName(bodyTag);
+}
+bool RenderObject::isHR() const
+{
+return node() && node()->hasTagName(hrTag);
+}
+bool RenderObject::isHTMLMarquee() const
+{
+return node() && node()->renderer() == this && node()->hasTagName(marqueeTag);
+}
+void RenderObject::addChild(RenderObject* newChild, RenderObject* beforeChild)
+{
+RenderObjectChildList* children = virtualChildren();
+ASSERT(children);
+if (!children)
+return;
+bool needsTable = false;
+if (newChild->isTableCol() && newChild->style()->display() == TABLE_COLUMN_GROUP)
+needsTable = !isTable();
+else if (newChild->isRenderBlock() && newChild->style()->display() == TABLE_CAPTION)
+needsTable = !isTable();
+else if (newChild->isTableSection())
+needsTable = !isTable();
+else if (newChild->isTableRow())
+needsTable = !isTableSection();
+else if (newChild->isTableCell()) {
+needsTable = !isTableRow();
+// I'm not 100% sure this is the best way to fix this, but without this
+// change we recurse infinitely when trying to render the CSS2 test page:
+// http://www.bath.ac.uk/%7Epy8ieh/internet/eviltests/htmlbodyheadrendering2.html.
+// See Radar 2925291.
+if (needsTable && isTableCell() && !children->firstChild() && !newChild->isTableCell())
+needsTable = false;
+}
+if (needsTable) {
+RenderTable* table;
+RenderObject* afterChild = beforeChild ? beforeChild->previousSibling() : children->lastChild();
+if (afterChild && afterChild->isAnonymous() && afterChild->isTable())
+table = toRenderTable(afterChild);
+else {
+table = new (renderArena()) RenderTable(document() /* is anonymous */);
+RefPtr<RenderStyle> newStyle = RenderStyle::create();
+newStyle->inheritFrom(style());
+newStyle->setDisplay(TABLE);
+table->setStyle(newStyle.release());
+addChild(table, beforeChild);
+}
+table->addChild(newChild);
+} else {
+// Just add it...
+children->insertChildNode(this, newChild, beforeChild);
+}
+RenderCounter::rendererSubtreeAttached(newChild);
+if (newChild->isText() && newChild->style()->textTransform() == CAPITALIZE) {
+RefPtr<StringImpl> textToTransform = toRenderText(newChild)->originalText();
+if (textToTransform)
+toRenderText(newChild)->setText(textToTransform.release(), true);
+}
+}
+void RenderObject::removeChild(RenderObject* oldChild)
+{
+RenderObjectChildList* children = virtualChildren();
+ASSERT(children);
+if (!children)
+return;
+// We do this here instead of in removeChildNode, since the only extremely low-level uses of remove/appendChildNode
+// cannot affect the positioned object list, and the floating object list is irrelevant (since the list gets cleared on
+// layout anyway).
+if (oldChild->isFloatingOrPositioned())
+toRenderBox(oldChild)->removeFloatingOrPositionedChildFromBlockLists();
+children->removeChildNode(this, oldChild);
+}
+RenderObject* RenderObject::nextInPreOrder() const
+{
+if (RenderObject* o = firstChild())
+return o;
+return nextInPreOrderAfterChildren();
+}
+RenderObject* RenderObject::nextInPreOrderAfterChildren() const
+{
+RenderObject* o;
+if (!(o = nextSibling())) {
+o = parent();
+while (o && !o->nextSibling())
+o = o->parent();
+if (o)
+o = o->nextSibling();
+}
+return o;
+}
+RenderObject* RenderObject::nextInPreOrder(RenderObject* stayWithin) const
+{
+if (RenderObject* o = firstChild())
+return o;
+return nextInPreOrderAfterChildren(stayWithin);
+}
+RenderObject* RenderObject::nextInPreOrderAfterChildren(RenderObject* stayWithin) const
+{
+if (this == stayWithin)
+return 0;
+const RenderObject* current = this;
+RenderObject* next;
+while (!(next = current->nextSibling())) {
+current = current->parent();
+if (!current || current == stayWithin)
+return 0;
+}
+return next;
+}
+RenderObject* RenderObject::previousInPreOrder() const
+{
+if (RenderObject* o = previousSibling()) {
+while (o->lastChild())
+o = o->lastChild();
+return o;
+}
+return parent();
+}
+RenderObject* RenderObject::childAt(unsigned index) const
+{
+RenderObject* child = firstChild();
+for (unsigned i = 0; child && i < index; i++)
+child = child->nextSibling();
+return child;
+}
+RenderObject* RenderObject::firstLeafChild() const
+{
+RenderObject* r = firstChild();
+while (r) {
+RenderObject* n = 0;
+n = r->firstChild();
+if (!n)
+break;
+r = n;
+}
+return r;
+}
+RenderObject* RenderObject::lastLeafChild() const
+{
+RenderObject* r = lastChild();
+while (r) {
+RenderObject* n = 0;
+n = r->lastChild();
+if (!n)
+break;
+r = n;
+}
+return r;
+}
+static void addLayers(RenderObject* obj, RenderLayer* parentLayer, RenderObject*& newObject,
+RenderLayer*& beforeChild)
+{
+if (obj->hasLayer()) {
+if (!beforeChild && newObject) {
+// We need to figure out the layer that follows newObject.  We only do
+// this the first time we find a child layer, and then we update the
+// pointer values for newObject and beforeChild used by everyone else.
+beforeChild = newObject->parent()->findNextLayer(parentLayer, newObject);
+newObject = 0;
+}
+parentLayer->addChild(toRenderBoxModelObject(obj)->layer(), beforeChild);
+return;
+}
+for (RenderObject* curr = obj->firstChild(); curr; curr = curr->nextSibling())
+addLayers(curr, parentLayer, newObject, beforeChild);
+}
+void RenderObject::addLayers(RenderLayer* parentLayer, RenderObject* newObject)
+{
+if (!parentLayer)
+return;
+RenderObject* object = newObject;
+RenderLayer* beforeChild = 0;
+WebCore::addLayers(this, parentLayer, object, beforeChild);
+}
+void RenderObject::removeLayers(RenderLayer* parentLayer)
+{
+if (!parentLayer)
+return;
+if (hasLayer()) {
+parentLayer->removeChild(toRenderBoxModelObject(this)->layer());
+return;
+}
+for (RenderObject* curr = firstChild(); curr; curr = curr->nextSibling())
+curr->removeLayers(parentLayer);
+}
+void RenderObject::moveLayers(RenderLayer* oldParent, RenderLayer* newParent)
+{
+if (!newParent)
+return;
+if (hasLayer()) {
+RenderLayer* layer = toRenderBoxModelObject(this)->layer();
+ASSERT(oldParent == layer->parent());
+if (oldParent)
+oldParent->removeChild(layer);
+newParent->addChild(layer);
+return;
+}
+for (RenderObject* curr = firstChild(); curr; curr = curr->nextSibling())
+curr->moveLayers(oldParent, newParent);
+}
+RenderLayer* RenderObject::findNextLayer(RenderLayer* parentLayer, RenderObject* startPoint,
+bool checkParent)
+{
+// Error check the parent layer passed in.  If it's null, we can't find anything.
+if (!parentLayer)
+return 0;
+// Step 1: If our layer is a child of the desired parent, then return our layer.
+RenderLayer* ourLayer = hasLayer() ? toRenderBoxModelObject(this)->layer() : 0;
+if (ourLayer && ourLayer->parent() == parentLayer)
+return ourLayer;
+// Step 2: If we don't have a layer, or our layer is the desired parent, then descend
+// into our siblings trying to find the next layer whose parent is the desired parent.
+if (!ourLayer || ourLayer == parentLayer) {
+for (RenderObject* curr = startPoint ? startPoint->nextSibling() : firstChild();
+curr; curr = curr->nextSibling()) {
+RenderLayer* nextLayer = curr->findNextLayer(parentLayer, 0, false);
+if (nextLayer)
+return nextLayer;
+}
+}
+// Step 3: If our layer is the desired parent layer, then we're finished.  We didn't
+// find anything.
+if (parentLayer == ourLayer)
+return 0;
+// Step 4: If |checkParent| is set, climb up to our parent and check its siblings that
+// follow us to see if we can locate a layer.
+if (checkParent && parent())
+return parent()->findNextLayer(parentLayer, this, true);
+return 0;
+}
+RenderLayer* RenderObject::enclosingLayer() const
+{
+const RenderObject* curr = this;
+while (curr) {
+RenderLayer* layer = curr->hasLayer() ? toRenderBoxModelObject(curr)->layer() : 0;
+if (layer)
+return layer;
+curr = curr->parent();
+}
+return 0;
+}
+RenderLayer* RenderObject::enclosingSelfPaintingLayer() const
+{
+const RenderObject* curr = this;
+while (curr) {
+RenderLayer* layer = curr->hasLayer() ? toRenderBoxModelObject(curr)->layer() : 0;
+if (layer && layer->isSelfPaintingLayer())
+return layer;
+curr = curr->parent();
+}
+return 0;
+}
+RenderBox* RenderObject::enclosingBox() const
+{
+RenderObject* curr = const_cast<RenderObject*>(this);
+while (curr) {
+if (curr->isBox())
+return toRenderBox(curr);
+curr = curr->parent();
+}
+ASSERT_NOT_REACHED();
+return 0;
+}
+RenderBoxModelObject* RenderObject::enclosingBoxModelObject() const
+{
+RenderObject* curr = const_cast<RenderObject*>(this);
+while (curr) {
+if (curr->isBoxModelObject())
+return toRenderBoxModelObject(curr);
+curr = curr->parent();
+}
+ASSERT_NOT_REACHED();
+return 0;
+}
+RenderBlock* RenderObject::firstLineBlock() const
+{
+return 0;
+}
+void RenderObject::setPrefWidthsDirty(bool b, bool markParents)
+{
+bool alreadyDirty = m_prefWidthsDirty;
+m_prefWidthsDirty = b;
+if (b && !alreadyDirty && markParents && (isText() || (style()->position() != FixedPosition && style()->position() != AbsolutePosition)))
+invalidateContainerPrefWidths();
+}
+void RenderObject::invalidateContainerPrefWidths()
+{
+// In order to avoid pathological behavior when inlines are deeply nested, we do include them
+// in the chain that we mark dirty (even though they're kind of irrelevant).
+RenderObject* o = isTableCell() ? containingBlock() : container();
+while (o && !o->m_prefWidthsDirty) {
+// Don't invalidate the outermost object of an unrooted subtree. That object will be
+// invalidated when the subtree is added to the document.
+RenderObject* container = o->isTableCell() ? o->containingBlock() : o->container();
+if (!container && !o->isRenderView())
+break;
+o->m_prefWidthsDirty = true;
+if (o->style()->position() == FixedPosition || o->style()->position() == AbsolutePosition)
+// A positioned object has no effect on the min/max width of its containing block ever.
+// We can optimize this case and not go up any further.
+break;
+o = container;
+}
+}
+void RenderObject::setLayerNeedsFullRepaint()
+{
+ASSERT(hasLayer());
+toRenderBoxModelObject(this)->layer()->setNeedsFullRepaint(true);
+}
+RenderBlock* RenderObject::containingBlock() const
+{
+if (isTableCell()) {
+const RenderTableCell* cell = toRenderTableCell(this);
+if (parent() && cell->section())
+return cell->table();
+return 0;
+}
+if (isRenderView())
+return const_cast<RenderView*>(toRenderView(this));
+RenderObject* o = parent();
+if (!isText() && m_style->position() == FixedPosition) {
+while (o && !o->isRenderView() && !(o->hasTransform() && o->isRenderBlock()))
+o = o->parent();
+} else if (!isText() && m_style->position() == AbsolutePosition) {
+while (o && (o->style()->position() == StaticPosition || (o->isInline() && !o->isReplaced())) && !o->isRenderView() && !(o->hasTransform() && o->isRenderBlock())) {
+// For relpositioned inlines, we return the nearest enclosing block.  We don't try
+// to return the inline itself.  This allows us to avoid having a positioned objects
+// list in all RenderInlines and lets us return a strongly-typed RenderBlock* result
+// from this method.  The container() method can actually be used to obtain the
+// inline directly.
+if (o->style()->position() == RelativePosition && o->isInline() && !o->isReplaced())
+return o->containingBlock();
+#if ENABLE(SVG)
+if (o->isSVGForeignObject()) //foreignObject is the containing block for contents inside it
+break;
+#endif
+o = o->parent();
+}
+} else {
+while (o && ((o->isInline() && !o->isReplaced()) || o->isTableRow() || o->isTableSection()
+|| o->isTableCol() || o->isFrameSet() || o->isMedia()
+#if ENABLE(SVG)
+|| o->isSVGContainer() || o->isSVGRoot()
+#endif
+))
+o = o->parent();
+}
+if (!o || !o->isRenderBlock())
+return 0; // This can still happen in case of an orphaned tree
+return toRenderBlock(o);
+}
+static bool mustRepaintFillLayers(const RenderObject* renderer, const FillLayer* layer)
+{
+// Nobody will use multiple layers without wanting fancy positioning.
+if (layer->next())
+return true;
+// Make sure we have a valid image.
+StyleImage* img = layer->image();
+if (!img || !img->canRender(renderer->style()->effectiveZoom()))
+return false;
+if (!layer->xPosition().isZero() || !layer->yPosition().isZero())
+return true;
+if (layer->size().type == SizeLength) {
+if (layer->size().size.width().isPercent() || layer->size().size.height().isPercent())
+return true;
+} else if (layer->size().type == Contain || layer->size().type == Cover || img->usesImageContainerSize())
+return true;
+return false;
+}
+bool RenderObject::mustRepaintBackgroundOrBorder() const
+{
+if (hasMask() && mustRepaintFillLayers(this, style()->maskLayers()))
+return true;
+// If we don't have a background/border/mask, then nothing to do.
+if (!hasBoxDecorations())
+return false;
+if (mustRepaintFillLayers(this, style()->backgroundLayers()))
+return true;
+// Our fill layers are ok.  Let's check border.
+if (style()->hasBorder()) {
+// Border images are not ok.
+StyleImage* borderImage = style()->borderImage().image();
+bool shouldPaintBorderImage = borderImage && borderImage->canRender(style()->effectiveZoom());
+// If the image hasn't loaded, we're still using the normal border style.
+if (shouldPaintBorderImage && borderImage->isLoaded())
+return true;
+}
+return false;
+}
+void RenderObject::drawLineForBoxSide(GraphicsContext* graphicsContext, int x1, int y1, int x2, int y2,
+BoxSide s, Color c, EBorderStyle style,
+int adjbw1, int adjbw2)
+{
+int width = (s == BSTop || s == BSBottom ? y2 - y1 : x2 - x1);
+if (style == DOUBLE && width < 3)
+style = SOLID;
+switch (style) {
+case BNONE:
+case BHIDDEN:
+return;
+case DOTTED:
+case DASHED:
+graphicsContext->setStrokeColor(c, m_style->colorSpace());
+graphicsContext->setStrokeThickness(width);
+graphicsContext->setStrokeStyle(style == DASHED ? DashedStroke : DottedStroke);
+if (width > 0)
+switch (s) {
+case BSBottom:
+case BSTop:
+graphicsContext->drawLine(IntPoint(x1, (y1 + y2) / 2), IntPoint(x2, (y1 + y2) / 2));
+break;
+case BSRight:
+case BSLeft:
+graphicsContext->drawLine(IntPoint((x1 + x2) / 2, y1), IntPoint((x1 + x2) / 2, y2));
+break;
+}
+break;
+case DOUBLE: {
+int third = (width + 1) / 3;
+if (adjbw1 == 0 && adjbw2 == 0) {
+graphicsContext->setStrokeStyle(NoStroke);
+graphicsContext->setFillColor(c, m_style->colorSpace());
+switch (s) {
+case BSTop:
+case BSBottom:
+graphicsContext->drawRect(IntRect(x1, y1, x2 - x1, third));
+graphicsContext->drawRect(IntRect(x1, y2 - third, x2 - x1, third));
+break;
+case BSLeft:
+graphicsContext->drawRect(IntRect(x1, y1 + 1, third, y2 - y1 - 1));
+graphicsContext->drawRect(IntRect(x2 - third, y1 + 1, third, y2 - y1 - 1));
+break;
+case BSRight:
+graphicsContext->drawRect(IntRect(x1, y1 + 1, third, y2 - y1 - 1));
+graphicsContext->drawRect(IntRect(x2 - third, y1 + 1, third, y2 - y1 - 1));
+break;
+}
+} else {
+int adjbw1bigthird = ((adjbw1 > 0) ? adjbw1 + 1 : adjbw1 - 1) / 3;
+int adjbw2bigthird = ((adjbw2 > 0) ? adjbw2 + 1 : adjbw2 - 1) / 3;
+switch (s) {
+case BSTop:
+drawLineForBoxSide(graphicsContext, x1 + max((-adjbw1 * 2 + 1) / 3, 0),
+y1, x2 - max((-adjbw2 * 2 + 1) / 3, 0), y1 + third,
+s, c, SOLID, adjbw1bigthird, adjbw2bigthird);
+drawLineForBoxSide(graphicsContext, x1 + max((adjbw1 * 2 + 1) / 3, 0),
+y2 - third, x2 - max((adjbw2 * 2 + 1) / 3, 0), y2,
+s, c, SOLID, adjbw1bigthird, adjbw2bigthird);
+break;
+case BSLeft:
+drawLineForBoxSide(graphicsContext, x1, y1 + max((-adjbw1 * 2 + 1) / 3, 0),
+x1 + third, y2 - max((-adjbw2 * 2 + 1) / 3, 0),
+s, c, SOLID, adjbw1bigthird, adjbw2bigthird);
+drawLineForBoxSide(graphicsContext, x2 - third, y1 + max((adjbw1 * 2 + 1) / 3, 0),
+x2, y2 - max((adjbw2 * 2 + 1) / 3, 0),
+s, c, SOLID, adjbw1bigthird, adjbw2bigthird);
+break;
+case BSBottom:
+drawLineForBoxSide(graphicsContext, x1 + max((adjbw1 * 2 + 1) / 3, 0),
+y1, x2 - max((adjbw2 * 2 + 1) / 3, 0), y1 + third,
+s, c, SOLID, adjbw1bigthird, adjbw2bigthird);
+drawLineForBoxSide(graphicsContext, x1 + max((-adjbw1 * 2 + 1) / 3, 0),
+y2 - third, x2 - max((-adjbw2 * 2 + 1) / 3, 0), y2,
+s, c, SOLID, adjbw1bigthird, adjbw2bigthird);
+break;
+case BSRight:
+drawLineForBoxSide(graphicsContext, x1, y1 + max((adjbw1 * 2 + 1) / 3, 0),
+x1 + third, y2 - max((adjbw2 * 2 + 1) / 3, 0),
+s, c, SOLID, adjbw1bigthird, adjbw2bigthird);
+drawLineForBoxSide(graphicsContext, x2 - third, y1 + max((-adjbw1 * 2 + 1) / 3, 0),
+x2, y2 - max((-adjbw2 * 2 + 1) / 3, 0),
+s, c, SOLID, adjbw1bigthird, adjbw2bigthird);
+break;
+default:
+break;
+}
+}
+break;
+}
+case RIDGE:
+case GROOVE:
+{
+EBorderStyle s1;
+EBorderStyle s2;
+if (style == GROOVE) {
+s1 = INSET;
+s2 = OUTSET;
+} else {
+s1 = OUTSET;
+s2 = INSET;
+}
+int adjbw1bighalf = ((adjbw1 > 0) ? adjbw1 + 1 : adjbw1 - 1) / 2;
+int adjbw2bighalf = ((adjbw2 > 0) ? adjbw2 + 1 : adjbw2 - 1) / 2;
+switch (s) {
+case BSTop:
+drawLineForBoxSide(graphicsContext, x1 + max(-adjbw1, 0) / 2, y1, x2 - max(-adjbw2, 0) / 2, (y1 + y2 + 1) / 2,
+s, c, s1, adjbw1bighalf, adjbw2bighalf);
+drawLineForBoxSide(graphicsContext, x1 + max(adjbw1 + 1, 0) / 2, (y1 + y2 + 1) / 2, x2 - max(adjbw2 + 1, 0) / 2, y2,
+s, c, s2, adjbw1 / 2, adjbw2 / 2);
+break;
+case BSLeft:
+drawLineForBoxSide(graphicsContext, x1, y1 + max(-adjbw1, 0) / 2, (x1 + x2 + 1) / 2, y2 - max(-adjbw2, 0) / 2,
+s, c, s1, adjbw1bighalf, adjbw2bighalf);
+drawLineForBoxSide(graphicsContext, (x1 + x2 + 1) / 2, y1 + max(adjbw1 + 1, 0) / 2, x2, y2 - max(adjbw2 + 1, 0) / 2,
+s, c, s2, adjbw1 / 2, adjbw2 / 2);
+break;
+case BSBottom:
+drawLineForBoxSide(graphicsContext, x1 + max(adjbw1, 0) / 2, y1, x2 - max(adjbw2, 0) / 2, (y1 + y2 + 1) / 2,
+s, c, s2, adjbw1bighalf, adjbw2bighalf);
+drawLineForBoxSide(graphicsContext, x1 + max(-adjbw1 + 1, 0) / 2, (y1 + y2 + 1) / 2, x2 - max(-adjbw2 + 1, 0) / 2, y2,
+s, c, s1, adjbw1 / 2, adjbw2 / 2);
+break;
+case BSRight:
+drawLineForBoxSide(graphicsContext, x1, y1 + max(adjbw1, 0) / 2, (x1 + x2 + 1) / 2, y2 - max(adjbw2, 0) / 2,
+s, c, s2, adjbw1bighalf, adjbw2bighalf);
+drawLineForBoxSide(graphicsContext, (x1 + x2 + 1) / 2, y1 + max(-adjbw1 + 1, 0) / 2, x2, y2 - max(-adjbw2 + 1, 0) / 2,
+s, c, s1, adjbw1 / 2, adjbw2 / 2);
+break;
+}
+break;
+}
+case INSET:
+if (s == BSTop || s == BSLeft)
+c = c.dark();
+// fall through
+case OUTSET:
+if (style == OUTSET && (s == BSBottom || s == BSRight))
+c = c.dark();
+// fall through
+case SOLID: {
+graphicsContext->setStrokeStyle(NoStroke);
+graphicsContext->setFillColor(c, m_style->colorSpace());
+ASSERT(x2 >= x1);
+ASSERT(y2 >= y1);
+if (!adjbw1 && !adjbw2) {
+graphicsContext->drawRect(IntRect(x1, y1, x2 - x1, y2 - y1));
+return;
+}
+FloatPoint quad[4];
+switch (s) {
+case BSTop:
+quad[0] = FloatPoint(x1 + max(-adjbw1, 0), y1);
+quad[1] = FloatPoint(x1 + max(adjbw1, 0), y2);
+quad[2] = FloatPoint(x2 - max(adjbw2, 0), y2);
+quad[3] = FloatPoint(x2 - max(-adjbw2, 0), y1);
+break;
+case BSBottom:
+quad[0] = FloatPoint(x1 + max(adjbw1, 0), y1);
+quad[1] = FloatPoint(x1 + max(-adjbw1, 0), y2);
+quad[2] = FloatPoint(x2 - max(-adjbw2, 0), y2);
+quad[3] = FloatPoint(x2 - max(adjbw2, 0), y1);
+break;
+case BSLeft:
+quad[0] = FloatPoint(x1, y1 + max(-adjbw1, 0));
+quad[1] = FloatPoint(x1, y2 - max(-adjbw2, 0));
+quad[2] = FloatPoint(x2, y2 - max(adjbw2, 0));
+quad[3] = FloatPoint(x2, y1 + max(adjbw1, 0));
+break;
+case BSRight:
+quad[0] = FloatPoint(x1, y1 + max(adjbw1, 0));
+quad[1] = FloatPoint(x1, y2 - max(adjbw2, 0));
+quad[2] = FloatPoint(x2, y2 - max(-adjbw2, 0));
+quad[3] = FloatPoint(x2, y1 + max(-adjbw1, 0));
+break;
+}
+graphicsContext->drawConvexPolygon(4, quad);
+break;
+}
+}
+}
+IntRect RenderObject::borderInnerRect(const IntRect& borderRect, unsigned short topWidth, unsigned short bottomWidth, unsigned short leftWidth, unsigned short rightWidth) const
+{
+return IntRect(
+borderRect.x() + leftWidth,
+borderRect.y() + topWidth,
+borderRect.width() - leftWidth - rightWidth,
+borderRect.height() - topWidth - bottomWidth);
+}
+#if HAVE(PATH_BASED_BORDER_RADIUS_DRAWING)
+void RenderObject::drawBoxSideFromPath(GraphicsContext* graphicsContext, IntRect borderRect, Path borderPath,
+float thickness, float drawThickness, BoxSide s, const RenderStyle* style,
+Color c, EBorderStyle borderStyle)
+{
+if (thickness <= 0)
+return;
+if (borderStyle == DOUBLE && thickness < 3)
+borderStyle = SOLID;
+switch (borderStyle) {
+case BNONE:
+case BHIDDEN:
+return;
+case DOTTED:
+case DASHED: {
+graphicsContext->setStrokeColor(c, style->colorSpace());
+// The stroke is doubled here because the provided path is the
+// outside edge of the border so half the stroke is clipped off.
+// The extra multiplier is so that the clipping mask can antialias
+// the edges to prevent jaggies.
+graphicsContext->setStrokeThickness(drawThickness * 2 * 1.1f);
+graphicsContext->setStrokeStyle(borderStyle == DASHED ? DashedStroke : DottedStroke);
+// If the number of dashes that fit in the path is odd and non-integral then we
+// will have an awkwardly-sized dash at the end of the path. To try to avoid that
+// here, we simply make the whitespace dashes ever so slightly bigger.
+// FIXME: This could be even better if we tried to manipulate the dash offset
+// and possibly the whiteSpaceWidth to get the corners dash-symmetrical.
+float patWidth = thickness * ((borderStyle == DASHED) ? 3.0f : 1.0f);
+float whiteSpaceWidth = patWidth;
+float numberOfDashes = borderPath.length() / patWidth;
+bool evenNumberOfFullDashes = !((int)numberOfDashes % 2);
+bool integralNumberOfDashes = !(numberOfDashes - (int)numberOfDashes);
+if (!evenNumberOfFullDashes && !integralNumberOfDashes) {
+float numberOfWhitespaceDashes = numberOfDashes / 2;
+whiteSpaceWidth += (patWidth  / numberOfWhitespaceDashes);
+}
+DashArray lineDash;
+lineDash.append(patWidth);
+lineDash.append(whiteSpaceWidth);
+graphicsContext->setLineDash(lineDash, patWidth);
+graphicsContext->addPath(borderPath);
+graphicsContext->strokePath();
+return;
+}
+case DOUBLE: {
+int outerBorderTopWidth = style->borderTopWidth() / 3;
+int outerBorderRightWidth = style->borderRightWidth() / 3;
+int outerBorderBottomWidth = style->borderBottomWidth() / 3;
+int outerBorderLeftWidth = style->borderLeftWidth() / 3;
+int innerBorderTopWidth = style->borderTopWidth() * 2 / 3;
+int innerBorderRightWidth = style->borderRightWidth() * 2 / 3;
+int innerBorderBottomWidth = style->borderBottomWidth() * 2 / 3;
+int innerBorderLeftWidth = style->borderLeftWidth() * 2 / 3;
+// We need certain integer rounding results
+if (style->borderTopWidth() % 3 == 2)
+outerBorderTopWidth += 1;
+if (style->borderRightWidth() % 3 == 2)
+outerBorderRightWidth += 1;
+if (style->borderBottomWidth() % 3 == 2)
+outerBorderBottomWidth += 1;
+if (style->borderLeftWidth() % 3 == 2)
+outerBorderLeftWidth += 1;
+if (style->borderTopWidth() % 3 == 1)
+innerBorderTopWidth += 1;
+if (style->borderRightWidth() % 3 == 1)
+innerBorderRightWidth += 1;
+if (style->borderBottomWidth() % 3 == 1)
+innerBorderBottomWidth += 1;
+if (style->borderLeftWidth() % 3 == 1)
+innerBorderLeftWidth += 1;
+// Get the inner border rects for both the outer border line and the inner border line
+IntRect outerBorderInnerRect = borderInnerRect(borderRect, outerBorderTopWidth, outerBorderBottomWidth,
+outerBorderLeftWidth, outerBorderRightWidth);
+IntRect innerBorderInnerRect = borderInnerRect(borderRect, innerBorderTopWidth, innerBorderBottomWidth,
+innerBorderLeftWidth, innerBorderRightWidth);
+// Get the inner radii for the outer border line
+IntSize outerBorderTopLeftInnerRadius, outerBorderTopRightInnerRadius, outerBorderBottomLeftInnerRadius,
+outerBorderBottomRightInnerRadius;
+style->getInnerBorderRadiiForRectWithBorderWidths(outerBorderInnerRect, outerBorderTopWidth, outerBorderBottomWidth,
+outerBorderLeftWidth, outerBorderRightWidth, outerBorderTopLeftInnerRadius, outerBorderTopRightInnerRadius,
+outerBorderBottomLeftInnerRadius, outerBorderBottomRightInnerRadius);
+// Get the inner radii for the inner border line
+IntSize innerBorderTopLeftInnerRadius, innerBorderTopRightInnerRadius, innerBorderBottomLeftInnerRadius,
+innerBorderBottomRightInnerRadius;
+style->getInnerBorderRadiiForRectWithBorderWidths(innerBorderInnerRect, innerBorderTopWidth, innerBorderBottomWidth,
+innerBorderLeftWidth, innerBorderRightWidth, innerBorderTopLeftInnerRadius, innerBorderTopRightInnerRadius,
+innerBorderBottomLeftInnerRadius, innerBorderBottomRightInnerRadius);
+// Draw inner border line
+graphicsContext->save();
+graphicsContext->addRoundedRectClip(innerBorderInnerRect, innerBorderTopLeftInnerRadius,
+innerBorderTopRightInnerRadius, innerBorderBottomLeftInnerRadius, innerBorderBottomRightInnerRadius);
+drawBoxSideFromPath(graphicsContext, borderRect, borderPath, thickness, drawThickness, s, style, c, SOLID);
+graphicsContext->restore();
+// Draw outer border line
+graphicsContext->save();
+graphicsContext->clipOutRoundedRect(outerBorderInnerRect, outerBorderTopLeftInnerRadius,
+outerBorderTopRightInnerRadius, outerBorderBottomLeftInnerRadius, outerBorderBottomRightInnerRadius);
+drawBoxSideFromPath(graphicsContext, borderRect, borderPath, thickness, drawThickness, s, style, c, SOLID);
+graphicsContext->restore();
+return;
+}
+case RIDGE:
+case GROOVE:
+{
+EBorderStyle s1;
+EBorderStyle s2;
+if (borderStyle == GROOVE) {
+s1 = INSET;
+s2 = OUTSET;
+} else {
+s1 = OUTSET;
+s2 = INSET;
+}
+IntRect halfBorderRect = borderInnerRect(borderRect, style->borderLeftWidth() / 2, style->borderBottomWidth() / 2,
+style->borderLeftWidth() / 2, style->borderRightWidth() / 2);
+IntSize topLeftHalfRadius, topRightHalfRadius, bottomLeftHalfRadius, bottomRightHalfRadius;
+style->getInnerBorderRadiiForRectWithBorderWidths(halfBorderRect, style->borderLeftWidth() / 2,
+style->borderBottomWidth() / 2, style->borderLeftWidth() / 2, style->borderRightWidth() / 2,
+topLeftHalfRadius, topRightHalfRadius, bottomLeftHalfRadius, bottomRightHalfRadius);
+// Paint full border
+drawBoxSideFromPath(graphicsContext, borderRect, borderPath, thickness, drawThickness, s, style, c, s1);
+// Paint inner only
+graphicsContext->save();
+graphicsContext->addRoundedRectClip(halfBorderRect, topLeftHalfRadius, topRightHalfRadius,
+bottomLeftHalfRadius, bottomRightHalfRadius);
+drawBoxSideFromPath(graphicsContext, borderRect, borderPath, thickness, drawThickness, s, style, c, s2);
+graphicsContext->restore();
+return;
+}
+case INSET:
+if (s == BSTop || s == BSLeft)
+c = c.dark();
+break;
+case OUTSET:
+if (s == BSBottom || s == BSRight)
+c = c.dark();
+break;
+default:
+break;
+}
+graphicsContext->setStrokeStyle(NoStroke);
+graphicsContext->setFillColor(c, style->colorSpace());
+graphicsContext->drawRect(borderRect);
+}
+#else
+void RenderObject::drawArcForBoxSide(GraphicsContext* graphicsContext, int x, int y, float thickness, IntSize radius,
+int angleStart, int angleSpan, BoxSide s, Color c,
+EBorderStyle style, bool firstCorner)
+{
+// FIXME: This function should be removed when all ports implement GraphicsContext::clipConvexPolygon()!!
+// At that time, everyone can use RenderObject::drawBoxSideFromPath() instead. This should happen soon.
+if ((style == DOUBLE && thickness / 2 < 3) || ((style == RIDGE || style == GROOVE) && thickness / 2 < 2))
+style = SOLID;
+switch (style) {
+case BNONE:
+case BHIDDEN:
+return;
+case DOTTED:
+case DASHED:
+graphicsContext->setStrokeColor(c, m_style->colorSpace());
+graphicsContext->setStrokeStyle(style == DOTTED ? DottedStroke : DashedStroke);
+graphicsContext->setStrokeThickness(thickness);
+graphicsContext->strokeArc(IntRect(x, y, radius.width() * 2, radius.height() * 2), angleStart, angleSpan);
+break;
+case DOUBLE: {
+float third = thickness / 3.0f;
+float innerThird = (thickness + 1.0f) / 6.0f;
+int shiftForInner = static_cast<int>(innerThird * 2.5f);
+int outerY = y;
+int outerHeight = radius.height() * 2;
+int innerX = x + shiftForInner;
+int innerY = y + shiftForInner;
+int innerWidth = (radius.width() - shiftForInner) * 2;
+int innerHeight = (radius.height() - shiftForInner) * 2;
+if (innerThird > 1 && (s == BSTop || (firstCorner && (s == BSLeft || s == BSRight)))) {
+outerHeight += 2;
+innerHeight += 2;
+}
+graphicsContext->setStrokeStyle(SolidStroke);
+graphicsContext->setStrokeColor(c, m_style->colorSpace());
+graphicsContext->setStrokeThickness(third);
+graphicsContext->strokeArc(IntRect(x, outerY, radius.width() * 2, outerHeight), angleStart, angleSpan);
+graphicsContext->setStrokeThickness(innerThird > 2 ? innerThird - 1 : innerThird);
+graphicsContext->strokeArc(IntRect(innerX, innerY, innerWidth, innerHeight), angleStart, angleSpan);
+break;
+}
+case GROOVE:
+case RIDGE: {
+Color c2;
+if ((style == RIDGE && (s == BSTop || s == BSLeft)) ||
+(style == GROOVE && (s == BSBottom || s == BSRight)))
+c2 = c.dark();
+else {
+c2 = c;
+c = c.dark();
+}
+graphicsContext->setStrokeStyle(SolidStroke);
+graphicsContext->setStrokeColor(c, m_style->colorSpace());
+graphicsContext->setStrokeThickness(thickness);
+graphicsContext->strokeArc(IntRect(x, y, radius.width() * 2, radius.height() * 2), angleStart, angleSpan);
+float halfThickness = (thickness + 1.0f) / 4.0f;
+int shiftForInner = static_cast<int>(halfThickness * 1.5f);
+graphicsContext->setStrokeColor(c2, m_style->colorSpace());
+graphicsContext->setStrokeThickness(halfThickness > 2 ? halfThickness - 1 : halfThickness);
+graphicsContext->strokeArc(IntRect(x + shiftForInner, y + shiftForInner, (radius.width() - shiftForInner) * 2,
+(radius.height() - shiftForInner) * 2), angleStart, angleSpan);
+break;
+}
+case INSET:
+if (s == BSTop || s == BSLeft)
+c = c.dark();
+case OUTSET:
+if (style == OUTSET && (s == BSBottom || s == BSRight))
+c = c.dark();
+case SOLID:
+graphicsContext->setStrokeStyle(SolidStroke);
+graphicsContext->setStrokeColor(c, m_style->colorSpace());
+graphicsContext->setStrokeThickness(thickness);
+graphicsContext->strokeArc(IntRect(x, y, radius.width() * 2, radius.height() * 2), angleStart, angleSpan);
+break;
+}
+}
+#endif
+void RenderObject::addPDFURLRect(GraphicsContext* context, const IntRect& rect)
+{
+if (rect.isEmpty())
+return;
+Node* n = node();
+if (!n || !n->isLink() || !n->isElementNode())
+return;
+const AtomicString& href = static_cast<Element*>(n)->getAttribute(hrefAttr);
+if (href.isNull())
+return;
+context->setURLForRect(n->document()->completeURL(href), rect);
+}
+void RenderObject::paintOutline(GraphicsContext* graphicsContext, int tx, int ty, int w, int h)
+{
+if (!hasOutline())
+return;
+RenderStyle* styleToUse = style();
+int ow = styleToUse->outlineWidth();
+EBorderStyle os = styleToUse->outlineStyle();
+Color oc = styleToUse->visitedDependentColor(CSSPropertyOutlineColor);
+int offset = styleToUse->outlineOffset();
+if (styleToUse->outlineStyleIsAuto() || hasOutlineAnnotation()) {
+if (!theme()->supportsFocusRing(styleToUse)) {
+// Only paint the focus ring by hand if the theme isn't able to draw the focus ring.
+Vector<IntRect> focusRingRects;
+addFocusRingRects(focusRingRects, tx, ty);
+if (styleToUse->outlineStyleIsAuto())
+graphicsContext->drawFocusRing(focusRingRects, ow, offset, oc);
+else
+addPDFURLRect(graphicsContext, unionRect(focusRingRects));
+}
+}
+if (styleToUse->outlineStyleIsAuto() || styleToUse->outlineStyle() == BNONE)
+return;
+tx -= offset;
+ty -= offset;
+w += 2 * offset;
+h += 2 * offset;
+if (h < 0 || w < 0)
+return;
+drawLineForBoxSide(graphicsContext, tx - ow, ty - ow, tx, ty + h + ow, BSLeft, oc, os, ow, ow);
+drawLineForBoxSide(graphicsContext, tx - ow, ty - ow, tx + w + ow, ty, BSTop, oc, os, ow, ow);
+drawLineForBoxSide(graphicsContext, tx + w, ty - ow, tx + w + ow, ty + h + ow, BSRight, oc, os, ow, ow);
+drawLineForBoxSide(graphicsContext, tx - ow, ty + h, tx + w + ow, ty + h + ow, BSBottom, oc, os, ow, ow);
+}
+IntRect RenderObject::absoluteBoundingBoxRect(bool useTransforms)
+{
+if (useTransforms) {
+Vector<FloatQuad> quads;
+absoluteQuads(quads);
+size_t n = quads.size();
+if (!n)
+return IntRect();
+IntRect result = quads[0].enclosingBoundingBox();
+for (size_t i = 1; i < n; ++i)
+result.unite(quads[i].enclosingBoundingBox());
+return result;
+}
+FloatPoint absPos = localToAbsolute();
+Vector<IntRect> rects;
+absoluteRects(rects, absPos.x(), absPos.y());
+size_t n = rects.size();
+if (!n)
+return IntRect();
+IntRect result = rects[0];
+for (size_t i = 1; i < n; ++i)
+result.unite(rects[i]);
+return result;
+}
+void RenderObject::absoluteFocusRingQuads(Vector<FloatQuad>& quads)
+{
+Vector<IntRect> rects;
+// FIXME: addFocusRingRects() needs to be passed this transform-unaware
+// localToAbsolute() offset here because RenderInline::addFocusRingRects()
+// implicitly assumes that. This doesn't work correctly with transformed
+// descendants.
+FloatPoint absolutePoint = localToAbsolute();
+addFocusRingRects(rects, absolutePoint.x(), absolutePoint.y());
+size_t count = rects.size();
+for (size_t i = 0; i < count; ++i) {
+IntRect rect = rects[i];
+rect.move(-absolutePoint.x(), -absolutePoint.y());
+quads.append(localToAbsoluteQuad(FloatQuad(rect)));
+}
+}
+void RenderObject::addAbsoluteRectForLayer(IntRect& result)
+{
+if (hasLayer())
+result.unite(absoluteBoundingBoxRect());
+for (RenderObject* current = firstChild(); current; current = current->nextSibling())
+current->addAbsoluteRectForLayer(result);
+}
+IntRect RenderObject::paintingRootRect(IntRect& topLevelRect)
+{
+IntRect result = absoluteBoundingBoxRect();
+topLevelRect = result;
+for (RenderObject* current = firstChild(); current; current = current->nextSibling())
+current->addAbsoluteRectForLayer(result);
+return result;
+}
+void RenderObject::paint(PaintInfo& /*paintInfo*/, int /*tx*/, int /*ty*/)
+{
+}
+RenderBoxModelObject* RenderObject::containerForRepaint() const
+{
+#if USE(ACCELERATED_COMPOSITING)
+if (RenderView* v = view()) {
+if (v->usesCompositing()) {
+RenderLayer* compLayer = enclosingLayer()->enclosingCompositingLayer();
+return compLayer ? compLayer->renderer() : 0;
+}
+}
+#endif
+// Do root-relative repaint.
+return 0;
+}
+void RenderObject::repaintUsingContainer(RenderBoxModelObject* repaintContainer, const IntRect& r, bool immediate)
+{
+if (!repaintContainer) {
+view()->repaintViewRectangle(r, immediate);
+return;
+}
+#if USE(ACCELERATED_COMPOSITING)
+RenderView* v = view();
+if (repaintContainer->isRenderView()) {
+ASSERT(repaintContainer == v);
+if (!v->hasLayer() || !v->layer()->isComposited() || v->layer()->backing()->paintingGoesToWindow()) {
+v->repaintViewRectangle(r, immediate);
+return;
+}
+}
+if (v->usesCompositing()) {
+ASSERT(repaintContainer->hasLayer() && repaintContainer->layer()->isComposited());
+repaintContainer->layer()->setBackingNeedsRepaintInRect(r);
+}
+#else
+if (repaintContainer->isRenderView())
+toRenderView(repaintContainer)->repaintViewRectangle(r, immediate);
+#endif
+}
+void RenderObject::repaint(bool immediate)
+{
+// Don't repaint if we're unrooted (note that view() still returns the view when unrooted)
+RenderView* view;
+if (!isRooted(&view))
+return;
+if (view->printing())
+return; // Don't repaint if we're printing.
+RenderBoxModelObject* repaintContainer = containerForRepaint();
+repaintUsingContainer(repaintContainer ? repaintContainer : view, clippedOverflowRectForRepaint(repaintContainer), immediate);
+}
+void RenderObject::repaintRectangle(const IntRect& r, bool immediate)
+{
+// Don't repaint if we're unrooted (note that view() still returns the view when unrooted)
+RenderView* view;
+if (!isRooted(&view))
+return;
+if (view->printing())
+return; // Don't repaint if we're printing.
+IntRect dirtyRect(r);
+// FIXME: layoutDelta needs to be applied in parts before/after transforms and
+// repaint containers. https://bugs.webkit.org/show_bug.cgi?id=23308
+dirtyRect.move(view->layoutDelta());
+RenderBoxModelObject* repaintContainer = containerForRepaint();
+computeRectForRepaint(repaintContainer, dirtyRect);
+repaintUsingContainer(repaintContainer ? repaintContainer : view, dirtyRect, immediate);
+}
+bool RenderObject::repaintAfterLayoutIfNeeded(RenderBoxModelObject* repaintContainer, const IntRect& oldBounds, const IntRect& oldOutlineBox, const IntRect* newBoundsPtr, const IntRect* newOutlineBoxRectPtr)
+{
+RenderView* v = view();
+if (v->printing())
+return false; // Don't repaint if we're printing.
+// This ASSERT fails due to animations.  See https://bugs.webkit.org/show_bug.cgi?id=37048
+// ASSERT(!newBoundsPtr || *newBoundsPtr == clippedOverflowRectForRepaint(repaintContainer));
+IntRect newBounds = newBoundsPtr ? *newBoundsPtr : clippedOverflowRectForRepaint(repaintContainer);
+IntRect newOutlineBox;
+bool fullRepaint = selfNeedsLayout();
+// Presumably a background or a border exists if border-fit:lines was specified.
+if (!fullRepaint && style()->borderFit() == BorderFitLines)
+fullRepaint = true;
+if (!fullRepaint) {
+// This ASSERT fails due to animations.  See https://bugs.webkit.org/show_bug.cgi?id=37048
+// ASSERT(!newOutlineBoxRectPtr || *newOutlineBoxRectPtr == outlineBoundsForRepaint(repaintContainer));
+newOutlineBox = newOutlineBoxRectPtr ? *newOutlineBoxRectPtr : outlineBoundsForRepaint(repaintContainer);
+if (newOutlineBox.location() != oldOutlineBox.location() || (mustRepaintBackgroundOrBorder() && (newBounds != oldBounds || newOutlineBox != oldOutlineBox)))
+fullRepaint = true;
+}
+if (!repaintContainer)
+repaintContainer = v;
+if (fullRepaint) {
+repaintUsingContainer(repaintContainer, oldBounds);
+if (newBounds != oldBounds)
+repaintUsingContainer(repaintContainer, newBounds);
+return true;
+}
+if (newBounds == oldBounds && newOutlineBox == oldOutlineBox)
+return false;
+int deltaLeft = newBounds.x() - oldBounds.x();
+if (deltaLeft > 0)
+repaintUsingContainer(repaintContainer, IntRect(oldBounds.x(), oldBounds.y(), deltaLeft, oldBounds.height()));
+else if (deltaLeft < 0)
+repaintUsingContainer(repaintContainer, IntRect(newBounds.x(), newBounds.y(), -deltaLeft, newBounds.height()));
+int deltaRight = newBounds.right() - oldBounds.right();
+if (deltaRight > 0)
+repaintUsingContainer(repaintContainer, IntRect(oldBounds.right(), newBounds.y(), deltaRight, newBounds.height()));
+else if (deltaRight < 0)
+repaintUsingContainer(repaintContainer, IntRect(newBounds.right(), oldBounds.y(), -deltaRight, oldBounds.height()));
+int deltaTop = newBounds.y() - oldBounds.y();
+if (deltaTop > 0)
+repaintUsingContainer(repaintContainer, IntRect(oldBounds.x(), oldBounds.y(), oldBounds.width(), deltaTop));
+else if (deltaTop < 0)
+repaintUsingContainer(repaintContainer, IntRect(newBounds.x(), newBounds.y(), newBounds.width(), -deltaTop));
+int deltaBottom = newBounds.bottom() - oldBounds.bottom();
+if (deltaBottom > 0)
+repaintUsingContainer(repaintContainer, IntRect(newBounds.x(), oldBounds.bottom(), newBounds.width(), deltaBottom));
+else if (deltaBottom < 0)
+repaintUsingContainer(repaintContainer, IntRect(oldBounds.x(), newBounds.bottom(), oldBounds.width(), -deltaBottom));
+if (newOutlineBox == oldOutlineBox)
+return false;
+// We didn't move, but we did change size.  Invalidate the delta, which will consist of possibly
+// two rectangles (but typically only one).
+RenderStyle* outlineStyle = outlineStyleForRepaint();
+int ow = outlineStyle->outlineSize();
+int width = abs(newOutlineBox.width() - oldOutlineBox.width());
+if (width) {
+int shadowLeft;
+int shadowRight;
+style()->getBoxShadowHorizontalExtent(shadowLeft, shadowRight);
+int borderRight = isBox() ? toRenderBox(this)->borderRight() : 0;
+int borderWidth = max(-outlineStyle->outlineOffset(), max(borderRight, max(style()->borderTopRightRadius().width(), style()->borderBottomRightRadius().width()))) + max(ow, shadowRight);
+IntRect rightRect(newOutlineBox.x() + min(newOutlineBox.width(), oldOutlineBox.width()) - borderWidth,
+newOutlineBox.y(),
+width + borderWidth,
+max(newOutlineBox.height(), oldOutlineBox.height()));
+int right = min(newBounds.right(), oldBounds.right());
+if (rightRect.x() < right) {
+rightRect.setWidth(min(rightRect.width(), right - rightRect.x()));
+repaintUsingContainer(repaintContainer, rightRect);
+}
+}
+int height = abs(newOutlineBox.height() - oldOutlineBox.height());
+if (height) {
+int shadowTop;
+int shadowBottom;
+style()->getBoxShadowVerticalExtent(shadowTop, shadowBottom);
+int borderBottom = isBox() ? toRenderBox(this)->borderBottom() : 0;
+int borderHeight = max(-outlineStyle->outlineOffset(), max(borderBottom, max(style()->borderBottomLeftRadius().height(), style()->borderBottomRightRadius().height()))) + max(ow, shadowBottom);
+IntRect bottomRect(newOutlineBox.x(),
+min(newOutlineBox.bottom(), oldOutlineBox.bottom()) - borderHeight,
+max(newOutlineBox.width(), oldOutlineBox.width()),
+height + borderHeight);
+int bottom = min(newBounds.bottom(), oldBounds.bottom());
+if (bottomRect.y() < bottom) {
+bottomRect.setHeight(min(bottomRect.height(), bottom - bottomRect.y()));
+repaintUsingContainer(repaintContainer, bottomRect);
+}
+}
+return false;
+}
+void RenderObject::repaintDuringLayoutIfMoved(const IntRect&)
+{
+}
+void RenderObject::repaintOverhangingFloats(bool)
+{
+}
+bool RenderObject::checkForRepaintDuringLayout() const
+{
+// FIXME: <https://bugs.webkit.org/show_bug.cgi?id=20885> It is probably safe to also require
+// m_everHadLayout. Currently, only RenderBlock::layoutBlock() adds this condition. See also
+// <https://bugs.webkit.org/show_bug.cgi?id=15129>.
+return !document()->view()->needsFullRepaint() && !hasLayer();
+}
+IntRect RenderObject::rectWithOutlineForRepaint(RenderBoxModelObject* repaintContainer, int outlineWidth)
+{
+IntRect r(clippedOverflowRectForRepaint(repaintContainer));
+r.inflate(outlineWidth);
+return r;
+}
+IntRect RenderObject::clippedOverflowRectForRepaint(RenderBoxModelObject*)
+{
+ASSERT_NOT_REACHED();
+return IntRect();
+}
+void RenderObject::computeRectForRepaint(RenderBoxModelObject* repaintContainer, IntRect& rect, bool fixed)
+{
+if (repaintContainer == this)
+return;
+if (RenderObject* o = parent()) {
+if (o->isBlockFlow()) {
+RenderBlock* cb = toRenderBlock(o);
+if (cb->hasColumns())
+cb->adjustRectForColumns(rect);
+}
+if (o->hasOverflowClip()) {
+// o->height() is inaccurate if we're in the middle of a layout of |o|, so use the
+// layer's size instead.  Even if the layer's size is wrong, the layer itself will repaint
+// anyway if its size does change.
+RenderBox* boxParent = toRenderBox(o);
+IntRect repaintRect(rect);
+repaintRect.move(-boxParent->layer()->scrolledContentOffset()); // For overflow:auto/scroll/hidden.
+IntRect boxRect(0, 0, boxParent->layer()->width(), boxParent->layer()->height());
+rect = intersection(repaintRect, boxRect);
+if (rect.isEmpty())
+return;
+}
+o->computeRectForRepaint(repaintContainer, rect, fixed);
+}
+}
+void RenderObject::dirtyLinesFromChangedChild(RenderObject*)
+{
+}
+#ifndef NDEBUG
+void RenderObject::showTreeForThis() const
+{
+if (node())
+node()->showTreeForThis();
+}
+void RenderObject::showRenderObject() const
+{
+showRenderObject(0);
+}
+void RenderObject::showRenderObject(int printedCharacters) const
+{
+// As this function is intended to be used when debugging, the
+// this pointer may be 0.
+if (!this) {
+fputs("(null)\n", stderr);
+return;
+}
+printedCharacters += fprintf(stderr, "%s %p", renderName(), this);
+if (node()) {
+if (printedCharacters)
+for (; printedCharacters < 39; printedCharacters++)
+fputc(' ', stderr);
+fputc('\t', stderr);
+node()->showNode();
+} else
+fputc('\n', stderr);
+}
+void RenderObject::showRenderTreeAndMark(const RenderObject* markedObject1, const char* markedLabel1, const RenderObject* markedObject2, const char* markedLabel2, int depth) const
+{
+int printedCharacters = 0;
+if (markedObject1 == this && markedLabel1)
+printedCharacters += fprintf(stderr, "%s", markedLabel1);
+if (markedObject2 == this && markedLabel2)
+printedCharacters += fprintf(stderr, "%s", markedLabel2);
+for (; printedCharacters < depth * 2; printedCharacters++)
+fputc(' ', stderr);
+showRenderObject(printedCharacters);
+if (!this)
+return;
+for (const RenderObject* child = firstChild(); child; child = child->nextSibling())
+child->showRenderTreeAndMark(markedObject1, markedLabel1, markedObject2, markedLabel2, depth + 1);
+}
+#endif // NDEBUG
+Color RenderObject::selectionBackgroundColor() const
+{
+Color color;
+if (style()->userSelect() != SELECT_NONE) {
+RefPtr<RenderStyle> pseudoStyle = getUncachedPseudoStyle(SELECTION);
+if (pseudoStyle && pseudoStyle->visitedDependentColor(CSSPropertyBackgroundColor).isValid())
+color = pseudoStyle->visitedDependentColor(CSSPropertyBackgroundColor).blendWithWhite();
+else
+color = frame()->selection()->isFocusedAndActive() ?
+theme()->activeSelectionBackgroundColor() :
+theme()->inactiveSelectionBackgroundColor();
+}
+return color;
+}
+Color RenderObject::selectionForegroundColor() const
+{
+Color color;
+if (style()->userSelect() == SELECT_NONE)
+return color;
+if (RefPtr<RenderStyle> pseudoStyle = getUncachedPseudoStyle(SELECTION)) {
+color = pseudoStyle->visitedDependentColor(CSSPropertyWebkitTextFillColor);
+if (!color.isValid())
+color = pseudoStyle->visitedDependentColor(CSSPropertyColor);
+} else
+color = frame()->selection()->isFocusedAndActive() ?
+theme()->activeSelectionForegroundColor() :
+theme()->inactiveSelectionForegroundColor();
+return color;
+}
+#if ENABLE(DRAG_SUPPORT)
+Node* RenderObject::draggableNode(bool dhtmlOK, bool uaOK, int x, int y, bool& dhtmlWillDrag) const
+{
+if (!dhtmlOK && !uaOK)
+return 0;
+for (const RenderObject* curr = this; curr; curr = curr->parent()) {
+Node* elt = curr->node();
+if (elt && elt->nodeType() == Node::TEXT_NODE) {
+// Since there's no way for the author to address the -webkit-user-drag style for a text node,
+// we use our own judgement.
+if (uaOK && view()->frameView()->frame()->eventHandler()->shouldDragAutoNode(curr->node(), IntPoint(x, y))) {
+dhtmlWillDrag = false;
+return curr->node();
+}
+if (elt->canStartSelection())
+// In this case we have a click in the unselected portion of text.  If this text is
+// selectable, we want to start the selection process instead of looking for a parent
+// to try to drag.
+return 0;
+} else {
+EUserDrag dragMode = curr->style()->userDrag();
+if (dhtmlOK && dragMode == DRAG_ELEMENT) {
+dhtmlWillDrag = true;
+return curr->node();
+}
+if (uaOK && dragMode == DRAG_AUTO
+&& view()->frameView()->frame()->eventHandler()->shouldDragAutoNode(curr->node(), IntPoint(x, y))) {
+dhtmlWillDrag = false;
+return curr->node();
+}
+}
+}
+return 0;
+}
+#endif // ENABLE(DRAG_SUPPORT)
+void RenderObject::selectionStartEnd(int& spos, int& epos) const
+{
+view()->selectionStartEnd(spos, epos);
+}
+void RenderObject::handleDynamicFloatPositionChange()
+{
+// We have gone from not affecting the inline status of the parent flow to suddenly
+// having an impact.  See if there is a mismatch between the parent flow's
+// childrenInline() state and our state.
+setInline(style()->isDisplayInlineType());
+if (isInline() != parent()->childrenInline()) {
+if (!isInline())
+toRenderBoxModelObject(parent())->childBecameNonInline(this);
+else {
+// An anonymous block must be made to wrap this inline.
+RenderBlock* block = toRenderBlock(parent())->createAnonymousBlock();
+RenderObjectChildList* childlist = parent()->virtualChildren();
+childlist->insertChildNode(parent(), block, this);
+block->children()->appendChildNode(block, childlist->removeChildNode(parent(), this));
+}
+}
+}
+void RenderObject::setAnimatableStyle(PassRefPtr<RenderStyle> style)
+{
+if (!isText() && style)
+setStyle(animation()->updateAnimations(this, style.get()));
+else
+setStyle(style);
+}
+StyleDifference RenderObject::adjustStyleDifference(StyleDifference diff, unsigned contextSensitiveProperties) const
+{
+#if USE(ACCELERATED_COMPOSITING)
+// If transform changed, and we are not composited, need to do a layout.
+if (contextSensitiveProperties & ContextSensitivePropertyTransform) {
+// Text nodes share style with their parents but transforms don't apply to them,
+// hence the !isText() check.
+// FIXME: when transforms are taken into account for overflow, we will need to do a layout.
+if (!isText() && (!hasLayer() || !toRenderBoxModelObject(this)->layer()->isComposited()))
+diff = StyleDifferenceLayout;
+else if (diff < StyleDifferenceRecompositeLayer)
+diff = StyleDifferenceRecompositeLayer;
+}
+// If opacity changed, and we are not composited, need to repaint (also
+// ignoring text nodes)
+if (contextSensitiveProperties & ContextSensitivePropertyOpacity) {
+if (!isText() && (!hasLayer() || !toRenderBoxModelObject(this)->layer()->isComposited()))
+diff = StyleDifferenceRepaintLayer;
+else if (diff < StyleDifferenceRecompositeLayer)
+diff = StyleDifferenceRecompositeLayer;
+}
+// The answer to requiresLayer() for plugins and iframes can change outside of the style system,
+// since it depends on whether we decide to composite these elements. When the layer status of
+// one of these elements changes, we need to force a layout.
+if (diff == StyleDifferenceEqual && style() && isBoxModelObject()) {
+if (hasLayer() != toRenderBoxModelObject(this)->requiresLayer())
+diff = StyleDifferenceLayout;
+}
+#else
+UNUSED_PARAM(contextSensitiveProperties);
+#endif
+// If we have no layer(), just treat a RepaintLayer hint as a normal Repaint.
+if (diff == StyleDifferenceRepaintLayer && !hasLayer())
+diff = StyleDifferenceRepaint;
+return diff;
+}
+void RenderObject::setStyle(PassRefPtr<RenderStyle> style)
+{
+if (m_style == style)
+return;
+StyleDifference diff = StyleDifferenceEqual;
+unsigned contextSensitiveProperties = ContextSensitivePropertyNone;
+if (m_style)
+diff = m_style->diff(style.get(), contextSensitiveProperties);
+diff = adjustStyleDifference(diff, contextSensitiveProperties);
+styleWillChange(diff, style.get());
+RefPtr<RenderStyle> oldStyle = m_style.release();
+m_style = style;
+updateFillImages(oldStyle ? oldStyle->backgroundLayers() : 0, m_style ? m_style->backgroundLayers() : 0);
+updateFillImages(oldStyle ? oldStyle->maskLayers() : 0, m_style ? m_style->maskLayers() : 0);
+updateImage(oldStyle ? oldStyle->borderImage().image() : 0, m_style ? m_style->borderImage().image() : 0);
+updateImage(oldStyle ? oldStyle->maskBoxImage().image() : 0, m_style ? m_style->maskBoxImage().image() : 0);
+// We need to ensure that view->maximalOutlineSize() is valid for any repaints that happen
+// during styleDidChange (it's used by clippedOverflowRectForRepaint()).
+if (m_style->outlineWidth() > 0 && m_style->outlineSize() > maximalOutlineSize(PaintPhaseOutline))
+toRenderView(document()->renderer())->setMaximalOutlineSize(m_style->outlineSize());
+styleDidChange(diff, oldStyle.get());
+if (!m_parent || isText())
+return;
+// Now that the layer (if any) has been updated, we need to adjust the diff again,
+// check whether we should layout now, and decide if we need to repaint.
+StyleDifference updatedDiff = adjustStyleDifference(diff, contextSensitiveProperties);
+if (diff <= StyleDifferenceLayoutPositionedMovementOnly) {
+if (updatedDiff == StyleDifferenceLayout)
+setNeedsLayoutAndPrefWidthsRecalc();
+else if (updatedDiff == StyleDifferenceLayoutPositionedMovementOnly)
+setNeedsPositionedMovementLayout();
+}
+if (updatedDiff == StyleDifferenceRepaintLayer || updatedDiff == StyleDifferenceRepaint) {
+// Do a repaint with the new style now, e.g., for example if we go from
+// not having an outline to having an outline.
+repaint();
+}
+}
+void RenderObject::setStyleInternal(PassRefPtr<RenderStyle> style)
+{
+m_style = style;
+}
+void RenderObject::styleWillChange(StyleDifference diff, const RenderStyle* newStyle)
+{
+if (m_style) {
+// If our z-index changes value or our visibility changes,
+// we need to dirty our stacking context's z-order list.
+if (newStyle) {
+bool visibilityChanged = m_style->visibility() != newStyle->visibility()
+|| m_style->zIndex() != newStyle->zIndex()
+|| m_style->hasAutoZIndex() != newStyle->hasAutoZIndex();
+#if ENABLE(DASHBOARD_SUPPORT)
+if (visibilityChanged)
+document()->setDashboardRegionsDirty(true);
+#endif
+if (visibilityChanged && AXObjectCache::accessibilityEnabled())
+document()->axObjectCache()->childrenChanged(this);
+// Keep layer hierarchy visibility bits up to date if visibility changes.
+if (m_style->visibility() != newStyle->visibility()) {
+if (RenderLayer* l = enclosingLayer()) {
+if (newStyle->visibility() == VISIBLE)
+l->setHasVisibleContent(true);
+else if (l->hasVisibleContent() && (this == l->renderer() || l->renderer()->style()->visibility() != VISIBLE)) {
+l->dirtyVisibleContentStatus();
+if (diff > StyleDifferenceRepaintLayer)
+repaint();
+}
+}
+}
+}
+if (m_parent && (diff == StyleDifferenceRepaint || newStyle->outlineSize() < m_style->outlineSize()))
+repaint();
+if (isFloating() && (m_style->floating() != newStyle->floating()))
+// For changes in float styles, we need to conceivably remove ourselves
+// from the floating objects list.
+toRenderBox(this)->removeFloatingOrPositionedChildFromBlockLists();
+else if (isPositioned() && (m_style->position() != newStyle->position()))
+// For changes in positioning styles, we need to conceivably remove ourselves
+// from the positioned objects list.
+toRenderBox(this)->removeFloatingOrPositionedChildFromBlockLists();
+s_affectsParentBlock = isFloatingOrPositioned() &&
+(!newStyle->isFloating() && newStyle->position() != AbsolutePosition && newStyle->position() != FixedPosition)
+&& parent() && (parent()->isBlockFlow() || parent()->isRenderInline());
+// reset style flags
+if (diff == StyleDifferenceLayout || diff == StyleDifferenceLayoutPositionedMovementOnly) {
+m_floating = false;
+m_positioned = false;
+m_relPositioned = false;
+}
+m_paintBackground = false;
+m_hasOverflowClip = false;
+m_hasTransform = false;
+m_hasReflection = false;
+} else
+s_affectsParentBlock = false;
+if (view()->frameView()) {
+bool shouldBlitOnFixedBackgroundImage = false;
+#if ENABLE(FAST_MOBILE_SCROLLING)
+// On low-powered/mobile devices, preventing blitting on a scroll can cause noticeable delays
+// when scrolling a page with a fixed background image. As an optimization, assuming there are
+// no fixed positoned elements on the page, we can acclerate scrolling (via blitting) if we
+// ignore the CSS property "background-attachment: fixed".
+shouldBlitOnFixedBackgroundImage = true;
+#endif
+bool newStyleSlowScroll = newStyle && !shouldBlitOnFixedBackgroundImage && newStyle->hasFixedBackgroundImage();
+bool oldStyleSlowScroll = m_style && !shouldBlitOnFixedBackgroundImage && m_style->hasFixedBackgroundImage();
+if (oldStyleSlowScroll != newStyleSlowScroll) {
+if (oldStyleSlowScroll)
+view()->frameView()->removeSlowRepaintObject();
+if (newStyleSlowScroll)
+view()->frameView()->addSlowRepaintObject();
+}
+}
+}
+void RenderObject::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
+{
+if (s_affectsParentBlock)
+handleDynamicFloatPositionChange();
+if (!m_parent)
+return;
+if (diff == StyleDifferenceLayout) {
+RenderCounter::rendererStyleChanged(this, oldStyle, m_style.get());
+// If the object already needs layout, then setNeedsLayout won't do
+// any work. But if the containing block has changed, then we may need
+// to mark the new containing blocks for layout. The change that can
+// directly affect the containing block of this object is a change to
+// the position style.
+if (m_needsLayout && oldStyle->position() != m_style->position())
+markContainingBlocksForLayout();
+setNeedsLayoutAndPrefWidthsRecalc();
+} else if (diff == StyleDifferenceLayoutPositionedMovementOnly)
+setNeedsPositionedMovementLayout();
+// Don't check for repaint here; we need to wait until the layer has been
+// updated by subclasses before we know if we have to repaint (in setStyle()).
+}
+void RenderObject::updateFillImages(const FillLayer* oldLayers, const FillLayer* newLayers)
+{
+// Optimize the common case
+if (oldLayers && !oldLayers->next() && newLayers && !newLayers->next() && (oldLayers->image() == newLayers->image()))
+return;
+// Go through the new layers and addClients first, to avoid removing all clients of an image.
+for (const FillLayer* currNew = newLayers; currNew; currNew = currNew->next()) {
+if (currNew->image())
+currNew->image()->addClient(this);
+}
+for (const FillLayer* currOld = oldLayers; currOld; currOld = currOld->next()) {
+if (currOld->image())
+currOld->image()->removeClient(this);
+}
+}
+void RenderObject::updateImage(StyleImage* oldImage, StyleImage* newImage)
+{
+if (oldImage != newImage) {
+if (oldImage)
+oldImage->removeClient(this);
+if (newImage)
+newImage->addClient(this);
+}
+}
+IntRect RenderObject::viewRect() const
+{
+return view()->viewRect();
+}
+FloatPoint RenderObject::localToAbsolute(FloatPoint localPoint, bool fixed, bool useTransforms) const
+{
+TransformState transformState(TransformState::ApplyTransformDirection, localPoint);
+mapLocalToContainer(0, fixed, useTransforms, transformState);
+transformState.flatten();
+return transformState.lastPlanarPoint();
+}
+FloatPoint RenderObject::absoluteToLocal(FloatPoint containerPoint, bool fixed, bool useTransforms) const
+{
+TransformState transformState(TransformState::UnapplyInverseTransformDirection, containerPoint);
+mapAbsoluteToLocalPoint(fixed, useTransforms, transformState);
+transformState.flatten();
+return transformState.lastPlanarPoint();
+}
+void RenderObject::mapLocalToContainer(RenderBoxModelObject* repaintContainer, bool fixed, bool useTransforms, TransformState& transformState) const
+{
+if (repaintContainer == this)
+return;
+RenderObject* o = parent();
+if (!o)
+return;
+IntSize columnOffset;
+o->adjustForColumns(columnOffset, roundedIntPoint(transformState.mappedPoint()));
+if (!columnOffset.isZero())
+transformState.move(columnOffset);
+if (o->hasOverflowClip())
+transformState.move(-toRenderBox(o)->layer()->scrolledContentOffset());
+o->mapLocalToContainer(repaintContainer, fixed, useTransforms, transformState);
+}
+void RenderObject::mapAbsoluteToLocalPoint(bool fixed, bool useTransforms, TransformState& transformState) const
+{
+RenderObject* o = parent();
+if (o) {
+o->mapAbsoluteToLocalPoint(fixed, useTransforms, transformState);
+if (o->hasOverflowClip())
+transformState.move(toRenderBox(o)->layer()->scrolledContentOffset());
+}
+}
+bool RenderObject::shouldUseTransformFromContainer(const RenderObject* containerObject) const
+{
+#if ENABLE(3D_RENDERING)
+// hasTransform() indicates whether the object has transform, transform-style or perspective. We just care about transform,
+// so check the layer's transform directly.
+return (hasLayer() && toRenderBoxModelObject(this)->layer()->transform()) || (containerObject && containerObject->style()->hasPerspective());
+#else
+UNUSED_PARAM(containerObject);
+return hasTransform();
+#endif
+}
+void RenderObject::getTransformFromContainer(const RenderObject* containerObject, const IntSize& offsetInContainer, TransformationMatrix& transform) const
+{
+transform.makeIdentity();
+transform.translate(offsetInContainer.width(), offsetInContainer.height());
+RenderLayer* layer;
+if (hasLayer() && (layer = toRenderBoxModelObject(this)->layer()) && layer->transform())
+transform.multLeft(layer->currentTransform());
+#if ENABLE(3D_RENDERING)
+if (containerObject && containerObject->hasLayer() && containerObject->style()->hasPerspective()) {
+// Perpsective on the container affects us, so we have to factor it in here.
+ASSERT(containerObject->hasLayer());
+FloatPoint perspectiveOrigin = toRenderBox(containerObject)->layer()->perspectiveOrigin();
+TransformationMatrix perspectiveMatrix;
+perspectiveMatrix.applyPerspective(containerObject->style()->perspective());
+transform.translateRight3d(-perspectiveOrigin.x(), -perspectiveOrigin.y(), 0);
+transform.multiply(perspectiveMatrix);
+transform.translateRight3d(perspectiveOrigin.x(), perspectiveOrigin.y(), 0);
+}
+#else
+UNUSED_PARAM(containerObject);
+#endif
+}
+FloatQuad RenderObject::localToContainerQuad(const FloatQuad& localQuad, RenderBoxModelObject* repaintContainer, bool fixed) const
+{
+// Track the point at the center of the quad's bounding box. As mapLocalToContainer() calls offsetFromContainer(),
+// it will use that point as the reference point to decide which column's transform to apply in multiple-column blocks.
+TransformState transformState(TransformState::ApplyTransformDirection, localQuad.boundingBox().center(), &localQuad);
+mapLocalToContainer(repaintContainer, fixed, true, transformState);
+transformState.flatten();
+return transformState.lastPlanarQuad();
+}
+IntSize RenderObject::offsetFromContainer(RenderObject* o, const IntPoint& point) const
+{
+ASSERT(o == container());
+IntSize offset;
+o->adjustForColumns(offset, point);
+if (o->hasOverflowClip())
+offset -= toRenderBox(o)->layer()->scrolledContentOffset();
+return offset;
+}
+IntSize RenderObject::offsetFromAncestorContainer(RenderObject* container) const
+{
+IntSize offset;
+IntPoint referencePoint;
+const RenderObject* currContainer = this;
+do {
+RenderObject* nextContainer = currContainer->container();
+ASSERT(nextContainer);  // This means we reached the top without finding container.
+if (!nextContainer)
+break;
+ASSERT(!currContainer->hasTransform());
+IntSize currentOffset = currContainer->offsetFromContainer(nextContainer, referencePoint);
+offset += currentOffset;
+referencePoint.move(currentOffset);
+currContainer = nextContainer;
+} while (currContainer != container);
+return offset;
+}
+IntRect RenderObject::localCaretRect(InlineBox*, int, int* extraWidthToEndOfLine)
+{
+if (extraWidthToEndOfLine)
+*extraWidthToEndOfLine = 0;
+return IntRect();
+}
+RenderView* RenderObject::view() const
+{
+return toRenderView(document()->renderer());
+}
+bool RenderObject::isRooted(RenderView** view)
+{
+RenderObject* o = this;
+while (o->parent())
+o = o->parent();
+if (!o->isRenderView())
+return false;
+if (view)
+*view = toRenderView(o);
+return true;
+}
+bool RenderObject::hasOutlineAnnotation() const
+{
+return node() && node()->isLink() && document()->printing();
+}
+RenderObject* RenderObject::container(RenderBoxModelObject* repaintContainer, bool* repaintContainerSkipped) const
+{
+if (repaintContainerSkipped)
+*repaintContainerSkipped = false;
+// This method is extremely similar to containingBlock(), but with a few notable
+// exceptions.
+// (1) It can be used on orphaned subtrees, i.e., it can be called safely even when
+// the object is not part of the primary document subtree yet.
+// (2) For normal flow elements, it just returns the parent.
+// (3) For absolute positioned elements, it will return a relative positioned inline.
+// containingBlock() simply skips relpositioned inlines and lets an enclosing block handle
+// the layout of the positioned object.  This does mean that calcAbsoluteHorizontal and
+// calcAbsoluteVertical have to use container().
+RenderObject* o = parent();
+if (isText())
+return o;
+EPosition pos = m_style->position();
+if (pos == FixedPosition) {
+// container() can be called on an object that is not in the
+// tree yet.  We don't call view() since it will assert if it
+// can't get back to the canvas.  Instead we just walk as high up
+// as we can.  If we're in the tree, we'll get the root.  If we
+// aren't we'll get the root of our little subtree (most likely
+// we'll just return 0).
+// FIXME: The definition of view() has changed to not crawl up the render tree.  It might
+// be safe now to use it.
+while (o && o->parent() && !(o->hasTransform() && o->isRenderBlock())) {
+if (repaintContainerSkipped && o == repaintContainer)
+*repaintContainerSkipped = true;
+o = o->parent();
+}
+} else if (pos == AbsolutePosition) {
+// Same goes here.  We technically just want our containing block, but
+// we may not have one if we're part of an uninstalled subtree.  We'll
+// climb as high as we can though.
+while (o && o->style()->position() == StaticPosition && !o->isRenderView() && !(o->hasTransform() && o->isRenderBlock())) {
+if (repaintContainerSkipped && o == repaintContainer)
+*repaintContainerSkipped = true;
+o = o->parent();
+}
+}
+return o;
+}
+bool RenderObject::isSelectionBorder() const
+{
+SelectionState st = selectionState();
+return st == SelectionStart || st == SelectionEnd || st == SelectionBoth;
+}
+void RenderObject::destroy()
+{
+// Destroy any leftover anonymous children.
+RenderObjectChildList* children = virtualChildren();
+if (children)
+children->destroyLeftoverChildren();
+// If this renderer is being autoscrolled, stop the autoscroll timer
+// FIXME: RenderObject::destroy should not get called with a renderer whose document
+// has a null frame, so we assert this. However, we don't want release builds to crash which is why we
+// check that the frame is not null.
+ASSERT(frame());
+if (frame() && frame()->eventHandler()->autoscrollRenderer() == this)
+frame()->eventHandler()->stopAutoscrollTimer(true);
+if (m_hasCounterNodeMap)
+RenderCounter::destroyCounterNodes(this);
+if (AXObjectCache::accessibilityEnabled()) {
+document()->axObjectCache()->childrenChanged(this->parent());
+document()->axObjectCache()->remove(this);
+}
+animation()->cancelAnimations(this);
+// By default no ref-counting. RenderWidget::destroy() doesn't call
+// this function because it needs to do ref-counting. If anything
+// in this function changes, be sure to fix RenderWidget::destroy() as well.
+remove();
+// FIXME: Would like to do this in RenderBoxModelObject, but the timing is so complicated that this can't easily
+// be moved into RenderBoxModelObject::destroy.
+if (hasLayer()) {
+setHasLayer(false);
+toRenderBoxModelObject(this)->destroyLayer();
+}
+arenaDelete(renderArena(), this);
+}
+void RenderObject::arenaDelete(RenderArena* arena, void* base)
+{
+if (m_style) {
+for (const FillLayer* bgLayer = m_style->backgroundLayers(); bgLayer; bgLayer = bgLayer->next()) {
+if (StyleImage* backgroundImage = bgLayer->image())
+backgroundImage->removeClient(this);
+}
+for (const FillLayer* maskLayer = m_style->maskLayers(); maskLayer; maskLayer = maskLayer->next()) {
+if (StyleImage* maskImage = maskLayer->image())
+maskImage->removeClient(this);
+}
+if (StyleImage* borderImage = m_style->borderImage().image())
+borderImage->removeClient(this);
+if (StyleImage* maskBoxImage = m_style->maskBoxImage().image())
+maskBoxImage->removeClient(this);
+}
+#ifndef NDEBUG
+void* savedBase = baseOfRenderObjectBeingDeleted;
+baseOfRenderObjectBeingDeleted = base;
+#endif
+delete this;
+#ifndef NDEBUG
+baseOfRenderObjectBeingDeleted = savedBase;
+#endif
+// Recover the size left there for us by operator delete and free the memory.
+arena->free(*(size_t*)base, base);
+}
+VisiblePosition RenderObject::positionForCoordinates(int x, int y)
+{
+return positionForPoint(IntPoint(x, y));
+}
+VisiblePosition RenderObject::positionForPoint(const IntPoint&)
+{
+return createVisiblePosition(caretMinOffset(), DOWNSTREAM);
+}
+void RenderObject::updateDragState(bool dragOn)
+{
+bool valueChanged = (dragOn != m_isDragging);
+m_isDragging = dragOn;
+if (valueChanged && style()->affectedByDragRules())
+node()->setNeedsStyleRecalc();
+for (RenderObject* curr = firstChild(); curr; curr = curr->nextSibling())
+curr->updateDragState(dragOn);
+}
+bool RenderObject::hitTest(const HitTestRequest& request, HitTestResult& result, const IntPoint& point, int tx, int ty, HitTestFilter hitTestFilter)
+{
+bool inside = false;
+if (hitTestFilter != HitTestSelf) {
+// First test the foreground layer (lines and inlines).
+inside = nodeAtPoint(request, result, point.x(), point.y(), tx, ty, HitTestForeground);
+// Test floats next.
+if (!inside)
+inside = nodeAtPoint(request, result, point.x(), point.y(), tx, ty, HitTestFloat);
+// Finally test to see if the mouse is in the background (within a child block's background).
+if (!inside)
+inside = nodeAtPoint(request, result, point.x(), point.y(), tx, ty, HitTestChildBlockBackgrounds);
+}
+// See if the mouse is inside us but not any of our descendants
+if (hitTestFilter != HitTestDescendants && !inside)
+inside = nodeAtPoint(request, result, point.x(), point.y(), tx, ty, HitTestBlockBackground);
+return inside;
+}
+void RenderObject::updateHitTestResult(HitTestResult& result, const IntPoint& point)
+{
+if (result.innerNode())
+return;
+Node* n = node();
+if (n) {
+result.setInnerNode(n);
+if (!result.innerNonSharedNode())
+result.setInnerNonSharedNode(n);
+result.setLocalPoint(point);
+}
+}
+bool RenderObject::nodeAtPoint(const HitTestRequest&, HitTestResult&, int /*x*/, int /*y*/, int /*tx*/, int /*ty*/, HitTestAction)
+{
+return false;
+}
+int RenderObject::lineHeight(bool firstLine, bool /*isRootLineBox*/) const
+{
+return style(firstLine)->computedLineHeight();
+}
+int RenderObject::baselinePosition(bool firstLine, bool isRootLineBox) const
+{
+const Font& f = style(firstLine)->font();
+return f.ascent() + (lineHeight(firstLine, isRootLineBox) - f.height()) / 2;
+}
+void RenderObject::scheduleRelayout()
+{
+if (isRenderView()) {
+FrameView* view = toRenderView(this)->frameView();
+if (view)
+view->scheduleRelayout();
+} else if (parent()) {
+FrameView* v = view() ? view()->frameView() : 0;
+if (v)
+v->scheduleRelayoutOfSubtree(this);
+}
+}
+void RenderObject::layout()
+{
+ASSERT(needsLayout());
+RenderObject* child = firstChild();
+while (child) {
+child->layoutIfNeeded();
+ASSERT(!child->needsLayout());
+child = child->nextSibling();
+}
+setNeedsLayout(false);
+}
+PassRefPtr<RenderStyle> RenderObject::uncachedFirstLineStyle(RenderStyle* style) const
+{
+if (!document()->usesFirstLineRules())
+return 0;
+ASSERT(!isText());
+RefPtr<RenderStyle> result;
+if (isBlockFlow()) {
+if (RenderBlock* firstLineBlock = this->firstLineBlock())
+result = firstLineBlock->getUncachedPseudoStyle(FIRST_LINE, style, firstLineBlock == this ? style : 0);
+} else if (!isAnonymous() && isRenderInline()) {
+RenderStyle* parentStyle = parent()->firstLineStyle();
+if (parentStyle != parent()->style())
+result = getUncachedPseudoStyle(FIRST_LINE_INHERITED, parentStyle, style);
+}
+return result.release();
+}
+RenderStyle* RenderObject::firstLineStyleSlowCase() const
+{
+ASSERT(document()->usesFirstLineRules());
+RenderStyle* style = m_style.get();
+const RenderObject* renderer = isText() ? parent() : this;
+if (renderer->isBlockFlow()) {
+if (RenderBlock* firstLineBlock = renderer->firstLineBlock())
+style = firstLineBlock->getCachedPseudoStyle(FIRST_LINE, style);
+} else if (!renderer->isAnonymous() && renderer->isRenderInline()) {
+RenderStyle* parentStyle = renderer->parent()->firstLineStyle();
+if (parentStyle != renderer->parent()->style()) {
+// A first-line style is in effect. Cache a first-line style for ourselves.
+style->setHasPseudoStyle(FIRST_LINE_INHERITED);
+style = renderer->getCachedPseudoStyle(FIRST_LINE_INHERITED, parentStyle);
+}
+}
+return style;
+}
+RenderStyle* RenderObject::getCachedPseudoStyle(PseudoId pseudo, RenderStyle* parentStyle) const
+{
+if (pseudo < FIRST_INTERNAL_PSEUDOID && !style()->hasPseudoStyle(pseudo))
+return 0;
+RenderStyle* cachedStyle = style()->getCachedPseudoStyle(pseudo);
+if (cachedStyle)
+return cachedStyle;
+RefPtr<RenderStyle> result = getUncachedPseudoStyle(pseudo, parentStyle);
+if (result)
+return style()->addCachedPseudoStyle(result.release());
+return 0;
+}
+PassRefPtr<RenderStyle> RenderObject::getUncachedPseudoStyle(PseudoId pseudo, RenderStyle* parentStyle, RenderStyle* ownStyle) const
+{
+if (pseudo < FIRST_INTERNAL_PSEUDOID && !ownStyle && !style()->hasPseudoStyle(pseudo))
+return 0;
+if (!parentStyle) {
+ASSERT(!ownStyle);
+parentStyle = style();
+}
+Node* n = node();
+while (n && !n->isElementNode())
+n = n->parentNode();
+if (!n)
+return 0;
+RefPtr<RenderStyle> result;
+if (pseudo == FIRST_LINE_INHERITED) {
+result = document()->styleSelector()->styleForElement(static_cast<Element*>(n), parentStyle, false);
+result->setStyleType(FIRST_LINE_INHERITED);
+} else
+result = document()->styleSelector()->pseudoStyleForElement(pseudo, static_cast<Element*>(n), parentStyle);
+return result.release();
+}
+static Color decorationColor(RenderObject* renderer)
+{
+Color result;
+if (renderer->style()->textStrokeWidth() > 0) {
+// Prefer stroke color if possible but not if it's fully transparent.
+result = renderer->style()->visitedDependentColor(CSSPropertyWebkitTextStrokeColor);
+if (result.alpha())
+return result;
+}
+result = renderer->style()->visitedDependentColor(CSSPropertyWebkitTextFillColor);
+return result;
+}
+void RenderObject::getTextDecorationColors(int decorations, Color& underline, Color& overline,
+Color& linethrough, bool quirksMode)
+{
+RenderObject* curr = this;
+do {
+int currDecs = curr->style()->textDecoration();
+if (currDecs) {
+if (currDecs & UNDERLINE) {
+decorations &= ~UNDERLINE;
+underline = decorationColor(curr);
+}
+if (currDecs & OVERLINE) {
+decorations &= ~OVERLINE;
+overline = decorationColor(curr);
+}
+if (currDecs & LINE_THROUGH) {
+decorations &= ~LINE_THROUGH;
+linethrough = decorationColor(curr);
+}
+}
+curr = curr->parent();
+if (curr && curr->isAnonymousBlock() && toRenderBlock(curr)->continuation())
+curr = toRenderBlock(curr)->continuation();
+} while (curr && decorations && (!quirksMode || !curr->node() ||
+(!curr->node()->hasTagName(aTag) && !curr->node()->hasTagName(fontTag))));
+// If we bailed out, use the element we bailed out at (typically a <font> or <a> element).
+if (decorations && curr) {
+if (decorations & UNDERLINE)
+underline = decorationColor(curr);
+if (decorations & OVERLINE)
+overline = decorationColor(curr);
+if (decorations & LINE_THROUGH)
+linethrough = decorationColor(curr);
+}
+}
+#if ENABLE(DASHBOARD_SUPPORT)
+void RenderObject::addDashboardRegions(Vector<DashboardRegionValue>& regions)
+{
+// Convert the style regions to absolute coordinates.
+if (style()->visibility() != VISIBLE || !isBox())
+return;
+RenderBox* box = toRenderBox(this);
+const Vector<StyleDashboardRegion>& styleRegions = style()->dashboardRegions();
+unsigned i, count = styleRegions.size();
+for (i = 0; i < count; i++) {
+StyleDashboardRegion styleRegion = styleRegions[i];
+int w = box->width();
+int h = box->height();
+DashboardRegionValue region;
+region.label = styleRegion.label;
+region.bounds = IntRect(styleRegion.offset.left().value(),
+styleRegion.offset.top().value(),
+w - styleRegion.offset.left().value() - styleRegion.offset.right().value(),
+h - styleRegion.offset.top().value() - styleRegion.offset.bottom().value());
+region.type = styleRegion.type;
+region.clip = region.bounds;
+computeAbsoluteRepaintRect(region.clip);
+if (region.clip.height() < 0) {
+region.clip.setHeight(0);
+region.clip.setWidth(0);
+}
+FloatPoint absPos = localToAbsolute();
+region.bounds.setX(absPos.x() + styleRegion.offset.left().value());
+region.bounds.setY(absPos.y() + styleRegion.offset.top().value());
+if (frame()) {
+float pageScaleFactor = frame()->page()->chrome()->scaleFactor();
+if (pageScaleFactor != 1.0f) {
+region.bounds.scale(pageScaleFactor);
+region.clip.scale(pageScaleFactor);
+}
+}
+regions.append(region);
+}
+}
+void RenderObject::collectDashboardRegions(Vector<DashboardRegionValue>& regions)
+{
+// RenderTexts don't have their own style, they just use their parent's style,
+// so we don't want to include them.
+if (isText())
+return;
+addDashboardRegions(regions);
+for (RenderObject* curr = firstChild(); curr; curr = curr->nextSibling())
+curr->collectDashboardRegions(regions);
+}
+#endif
+bool RenderObject::willRenderImage(CachedImage*)
+{
+// Without visibility we won't render (and therefore don't care about animation).
+if (style()->visibility() != VISIBLE)
+return false;
+// If we're not in a window (i.e., we're dormant from being put in the b/f cache or in a background tab)
+// then we don't want to render either.
+return !document()->inPageCache() && !document()->view()->isOffscreen();
+}
+int RenderObject::maximalOutlineSize(PaintPhase p) const
+{
+if (p != PaintPhaseOutline && p != PaintPhaseSelfOutline && p != PaintPhaseChildOutlines)
+return 0;
+return toRenderView(document()->renderer())->maximalOutlineSize();
+}
+int RenderObject::caretMinOffset() const
+{
+return 0;
+}
+int RenderObject::caretMaxOffset() const
+{
+if (isReplaced())
+return node() ? max(1U, node()->childNodeCount()) : 1;
+if (isHR())
+return 1;
+return 0;
+}
+unsigned RenderObject::caretMaxRenderedOffset() const
+{
+return 0;
+}
+int RenderObject::previousOffset(int current) const
+{
+return current - 1;
+}
+int RenderObject::previousOffsetForBackwardDeletion(int current) const
+{
+return current - 1;
+}
+int RenderObject::nextOffset(int current) const
+{
+return current + 1;
+}
+void RenderObject::adjustRectForOutlineAndShadow(IntRect& rect) const
+{
+int outlineSize = outlineStyleForRepaint()->outlineSize();
+if (const ShadowData* boxShadow = style()->boxShadow()) {
+int shadowLeft = 0;
+int shadowRight = 0;
+int shadowTop = 0;
+int shadowBottom = 0;
+do {
+if (boxShadow->style() == Normal) {
+shadowLeft = min(boxShadow->x() - boxShadow->blur() - boxShadow->spread() - outlineSize, shadowLeft);
+shadowRight = max(boxShadow->x() + boxShadow->blur() + boxShadow->spread() + outlineSize, shadowRight);
+shadowTop = min(boxShadow->y() - boxShadow->blur() - boxShadow->spread() - outlineSize, shadowTop);
+shadowBottom = max(boxShadow->y() + boxShadow->blur() + boxShadow->spread() + outlineSize, shadowBottom);
+}
+boxShadow = boxShadow->next();
+} while (boxShadow);
+rect.move(shadowLeft, shadowTop);
+rect.setWidth(rect.width() - shadowLeft + shadowRight);
+rect.setHeight(rect.height() - shadowTop + shadowBottom);
+} else
+rect.inflate(outlineSize);
+}
+AnimationController* RenderObject::animation() const
+{
+return frame()->animation();
+}
+void RenderObject::imageChanged(CachedImage* image, const IntRect* rect)
+{
+imageChanged(static_cast<WrappedImagePtr>(image), rect);
+}
+RenderBoxModelObject* RenderObject::offsetParent() const
+{
+// If any of the following holds true return null and stop this algorithm:
+// A is the root element.
+// A is the HTML body element.
+// The computed value of the position property for element A is fixed.
+if (isRoot() || isBody() || (isPositioned() && style()->position() == FixedPosition))
+return 0;
+// If A is an area HTML element which has a map HTML element somewhere in the ancestor
+// chain return the nearest ancestor map HTML element and stop this algorithm.
+// FIXME: Implement!
+// Return the nearest ancestor element of A for which at least one of the following is
+// true and stop this algorithm if such an ancestor is found:
+//     * The computed value of the position property is not static.
+//     * It is the HTML body element.
+//     * The computed value of the position property of A is static and the ancestor
+//       is one of the following HTML elements: td, th, or table.
+//     * Our own extension: if there is a difference in the effective zoom
+bool skipTables = isPositioned() || isRelPositioned();
+float currZoom = style()->effectiveZoom();
+RenderObject* curr = parent();
+while (curr && (!curr->node() ||
+(!curr->isPositioned() && !curr->isRelPositioned() && !curr->isBody()))) {
+Node* element = curr->node();
+if (!skipTables && element) {
+bool isTableElement = element->hasTagName(tableTag) ||
+element->hasTagName(tdTag) ||
+element->hasTagName(thTag);
+#if ENABLE(WML)
+if (!isTableElement && element->isWMLElement())
+isTableElement = element->hasTagName(WMLNames::tableTag) ||
+element->hasTagName(WMLNames::tdTag);
+#endif
+if (isTableElement)
+break;
+}
+float newZoom = curr->style()->effectiveZoom();
+if (currZoom != newZoom)
+break;
+currZoom = newZoom;
+curr = curr->parent();
+}
+return curr && curr->isBoxModelObject() ? toRenderBoxModelObject(curr) : 0;
+}
+VisiblePosition RenderObject::createVisiblePosition(int offset, EAffinity affinity)
+{
+// If this is a non-anonymous renderer in an editable area, then it's simple.
+if (Node* node = this->node()) {
+if (!node->isContentEditable()) {
+// If it can be found, we prefer a visually equivalent position that is editable.
+Position position(node, offset);
+Position candidate = position.downstream(Position::CanCrossEditingBoundary);
+if (candidate.node()->isContentEditable())
+return VisiblePosition(candidate, affinity);
+candidate = position.upstream(Position::CanCrossEditingBoundary);
+if (candidate.node()->isContentEditable())
+return VisiblePosition(candidate, affinity);
+}
+return VisiblePosition(node, offset, affinity);
+}
+// We don't want to cross the boundary between editable and non-editable
+// regions of the document, but that is either impossible or at least
+// extremely unlikely in any normal case because we stop as soon as we
+// find a single non-anonymous renderer.
+// Find a nearby non-anonymous renderer.
+RenderObject* child = this;
+while (RenderObject* parent = child->parent()) {
+// Find non-anonymous content after.
+RenderObject* renderer = child;
+while ((renderer = renderer->nextInPreOrder(parent))) {
+if (Node* node = renderer->node())
+return VisiblePosition(node, 0, DOWNSTREAM);
+}
+// Find non-anonymous content before.
+renderer = child;
+while ((renderer = renderer->previousInPreOrder())) {
+if (renderer == parent)
+break;
+if (Node* node = renderer->node())
+return VisiblePosition(lastDeepEditingPositionForNode(node), DOWNSTREAM);
+}
+// Use the parent itself unless it too is anonymous.
+if (Node* node = parent->node())
+return VisiblePosition(node, 0, DOWNSTREAM);
+// Repeat at the next level up.
+child = parent;
+}
+// Everything was anonymous. Give up.
+return VisiblePosition();
+}
+VisiblePosition RenderObject::createVisiblePosition(const Position& position)
+{
+if (position.isNotNull())
+return VisiblePosition(position);
+ASSERT(!node());
+return createVisiblePosition(0, DOWNSTREAM);
+}
+#if ENABLE(SVG)
+RenderSVGResourceContainer* RenderObject::toRenderSVGResourceContainer()
+{
+ASSERT_NOT_REACHED();
+return 0;
+}
+FloatRect RenderObject::objectBoundingBox() const
+{
+ASSERT_NOT_REACHED();
+return FloatRect();
+}
+FloatRect RenderObject::strokeBoundingBox() const
+{
+ASSERT_NOT_REACHED();
+return FloatRect();
+}
+// Returns the smallest rectangle enclosing all of the painted content
+// respecting clipping, masking, filters, opacity, stroke-width and markers
+FloatRect RenderObject::repaintRectInLocalCoordinates() const
+{
+ASSERT_NOT_REACHED();
+return FloatRect();
+}
+AffineTransform RenderObject::localTransform() const
+{
+static const AffineTransform identity;
+return identity;
+}
+const AffineTransform& RenderObject::localToParentTransform() const
+{
+static const AffineTransform identity;
+return identity;
+}
+bool RenderObject::nodeAtFloatPoint(const HitTestRequest&, HitTestResult&, const FloatPoint&, HitTestAction)
+{
+ASSERT_NOT_REACHED();
+return false;
+}
+#endif // ENABLE(SVG)
+} // namespace WebCore
+#ifndef NDEBUG
+void showTree(const WebCore::RenderObject* ro)
+{
+if (ro)
+ro->showTreeForThis();
+}
+void showRenderTree(const WebCore::RenderObject* object1)
+{
+showRenderTree(object1, 0);
+}
+void showRenderTree(const WebCore::RenderObject* object1, const WebCore::RenderObject* object2)
+{
+if (object1) {
+const WebCore::RenderObject* root = object1;
+while (root->parent())
+root = root->parent();
+root->showRenderTreeAndMark(object1, "*", object2, "-", 0);
+}
+}
+#endif