WebCore/rendering/SVGRenderSupport.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2007, 2008 Rob Buis <buis@kde.org>
  *           (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
  *           (C) 2007 Eric Seidel <eric@webkit.org>
  *           (C) 2009 Google, Inc.  All rights reserved.
  *           (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) Research In Motion Limited 2009-2010. 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"

 #if ENABLE(SVG)
 #include "SVGRenderSupport.h"

 #include "AffineTransform.h"
 #include "Document.h"
 #include "ImageBuffer.h"
 #include "NodeRenderStyle.h"
 #include "RenderObject.h"
 #include "RenderSVGContainer.h"
 #include "RenderSVGResource.h"
 #include "RenderSVGResourceClipper.h"
 #include "RenderSVGResourceFilter.h"
 #include "RenderSVGResourceMarker.h"
 #include "RenderSVGResourceMasker.h"
 #include "RenderView.h"
 #include "SVGStyledElement.h"
 #include "SVGURIReference.h"
 #include "TransformState.h"
 #include <wtf/UnusedParam.h>

 namespace WebCore {

 SVGRenderBase::~SVGRenderBase()
 {
 }

 IntRect SVGRenderBase::clippedOverflowRectForRepaint(RenderObject* object, RenderBoxModelObject* repaintContainer)
 {
     // Return early for any cases where we don't actually paint
     if (object->style()->visibility() != VISIBLE && !object->enclosingLayer()->hasVisibleContent())
         return IntRect();

     // Pass our local paint rect to computeRectForRepaint() which will
     // map to parent coords and recurse up the parent chain.
     IntRect repaintRect = enclosingIntRect(object->repaintRectInLocalCoordinates());
     object->computeRectForRepaint(repaintContainer, repaintRect);
     return repaintRect;
 }

 void SVGRenderBase::computeRectForRepaint(RenderObject* object, RenderBoxModelObject* repaintContainer, IntRect& repaintRect, bool fixed)
 {
     object->style()->svgStyle()->inflateForShadow(repaintRect);

     // Translate to coords in our parent renderer, and then call computeRectForRepaint on our parent
     repaintRect = object->localToParentTransform().mapRect(repaintRect);
     object->parent()->computeRectForRepaint(repaintContainer, repaintRect, fixed);
 }

 void SVGRenderBase::mapLocalToContainer(const RenderObject* object, RenderBoxModelObject* repaintContainer, bool fixed , bool useTransforms, TransformState& transformState)
 {
     ASSERT(!fixed); // We should have no fixed content in the SVG rendering tree.
     ASSERT(useTransforms); // Mapping a point through SVG w/o respecting transforms is useless.
     transformState.applyTransform(object->localToParentTransform());
     object->parent()->mapLocalToContainer(repaintContainer, fixed, useTransforms, transformState);
 }

 bool SVGRenderBase::prepareToRenderSVGContent(RenderObject* object, RenderObject::PaintInfo& paintInfo, const FloatRect& repaintRect, RenderSVGResourceFilter*& filter, RenderSVGResourceFilter* rootFilter)
 {
 #if !ENABLE(FILTERS)
     UNUSED_PARAM(filter);
     UNUSED_PARAM(rootFilter);
 #endif

     ASSERT(object);
     SVGElement* svgElement = static_cast<SVGElement*>(object->node());
     ASSERT(svgElement && svgElement->document() && svgElement->isStyled());

     SVGStyledElement* styledElement = static_cast<SVGStyledElement*>(svgElement);
     RenderStyle* style = object->style();
     ASSERT(style);

     const SVGRenderStyle* svgStyle = style->svgStyle();
     ASSERT(svgStyle);

     // Setup transparency layers before setting up filters!
     float opacity = style->opacity();
     if (opacity < 1.0f) {
         paintInfo.context->clip(repaintRect);
         paintInfo.context->beginTransparencyLayer(opacity);
     }

     if (const ShadowData* shadow = svgStyle->shadow()) {
         paintInfo.context->clip(repaintRect);
         paintInfo.context->setShadow(IntSize(shadow->x(), shadow->y()), shadow->blur(), shadow->color(), style->colorSpace());
         paintInfo.context->beginTransparencyLayer(1.0f);
     }

 #if ENABLE(FILTERS)
     AtomicString filterId(svgStyle->filterResource());
 #endif

     AtomicString clipperId(svgStyle->clipperResource());
     AtomicString maskerId(svgStyle->maskerResource());

     Document* document = object->document();

 #if ENABLE(FILTERS)
     RenderSVGResourceFilter* newFilter = getRenderSVGResourceById<RenderSVGResourceFilter>(document, filterId);
     if (newFilter == rootFilter) {
         // Catch <text filter="url(#foo)">Test<tspan filter="url(#foo)">123</tspan></text>.
         // The filter is NOT meant to be applied twice in that case!
         filter = 0;
         filterId = String();
     } else
         filter = newFilter;
 #endif

     if (RenderSVGResourceMasker* masker = getRenderSVGResourceById<RenderSVGResourceMasker>(document, maskerId)) {
         if (!masker->applyResource(object, style, paintInfo.context, ApplyToDefaultMode))
             return false;
     } else if (!maskerId.isEmpty())
         svgElement->document()->accessSVGExtensions()->addPendingResource(maskerId, styledElement);

     if (RenderSVGResourceClipper* clipper = getRenderSVGResourceById<RenderSVGResourceClipper>(document, clipperId))
         clipper->applyResource(object, style, paintInfo.context, ApplyToDefaultMode);
     else if (!clipperId.isEmpty())
         svgElement->document()->accessSVGExtensions()->addPendingResource(clipperId, styledElement);

 #if ENABLE(FILTERS)
     if (filter) {
         if (!filter->applyResource(object, style, paintInfo.context, ApplyToDefaultMode))
             return false;
     } else if (!filterId.isEmpty())
         svgElement->document()->accessSVGExtensions()->addPendingResource(filterId, styledElement);
 #endif

     return true;
 }

 void SVGRenderBase::finishRenderSVGContent(RenderObject* object, RenderObject::PaintInfo& paintInfo, RenderSVGResourceFilter*& filter, GraphicsContext* savedContext)
 {
 #if !ENABLE(FILTERS)
     UNUSED_PARAM(filter);
     UNUSED_PARAM(savedContext);
 #endif

     ASSERT(object);

     const RenderStyle* style = object->style();
     ASSERT(style);

 #if ENABLE(FILTERS)
     if (filter) {
         filter->postApplyResource(object, paintInfo.context, ApplyToDefaultMode);
         paintInfo.context = savedContext;
     }
 #endif

     float opacity = style->opacity();
     if (opacity < 1.0f)
         paintInfo.context->endTransparencyLayer();

     // This needs to be done separately from opacity, because if both properties are set,
     // then the transparency layers are nested.
     if (style->svgStyle()->shadow())
         paintInfo.context->endTransparencyLayer();
 }

 void renderSubtreeToImage(ImageBuffer* image, RenderObject* item)
 {
     ASSERT(item);
     ASSERT(image);
     ASSERT(image->context());

     // FIXME: This sets the rect to the viewable area of the current frame. This
     // is used to support text drawings to the ImageBuffer. See bug 30399.
     IntRect rect;
     FrameView* frameView = item->document()->view();
     if (frameView)
         rect = IntRect(0, 0, frameView->visibleWidth(), frameView->visibleHeight());
     RenderObject::PaintInfo info(image->context(), rect, PaintPhaseForeground, 0, 0, 0);

     // FIXME: isSVGContainer returns true for RenderSVGViewportContainer, so if this is ever
     // called with one of those, we will read from the wrong offset in an object due to a bad cast.
     RenderSVGContainer* svgContainer = 0;
     if (item && item->isSVGContainer())
         svgContainer = toRenderSVGContainer(item);

     bool drawsContents = svgContainer ? svgContainer->drawsContents() : false;
     if (svgContainer && !drawsContents)
         svgContainer->setDrawsContents(true);

     item->layoutIfNeeded();
     item->paint(info, 0, 0);

     if (svgContainer && !drawsContents)
         svgContainer->setDrawsContents(false);
 }

 void clampImageBufferSizeToViewport(FrameView* frameView, IntSize& size)
 {
     if (!frameView)
         return;

     int viewWidth = frameView->visibleWidth();
     int viewHeight = frameView->visibleHeight();

     if (size.width() > viewWidth)
         size.setWidth(viewWidth);

     if (size.height() > viewHeight)
         size.setHeight(viewHeight);
 }

 FloatRect SVGRenderBase::computeContainerBoundingBox(const RenderObject* container, bool includeAllPaintedContent)
 {
     FloatRect boundingBox;

     RenderObject* current = container->firstChild();
     for (; current != 0; current = current->nextSibling()) {
         FloatRect childBBox = includeAllPaintedContent ? current->repaintRectInLocalCoordinates() : current->objectBoundingBox();
         FloatRect childBBoxInLocalCoords = current->localToParentTransform().mapRect(childBBox);
         boundingBox.unite(childBBoxInLocalCoords);
     }

     return boundingBox;
 }

 void SVGRenderBase::layoutChildren(RenderObject* start, bool selfNeedsLayout)
 {
     for (RenderObject* child = start->firstChild(); child; child = child->nextSibling()) {
         // Only force our kids to layout if we're being asked to relayout as a result of a parent changing
         // FIXME: We should be able to skip relayout of non-relative kids when only bounds size has changed
         // that's a possible future optimization using LayoutState
         // http://bugs.webkit.org/show_bug.cgi?id=15391
         bool needsLayout = selfNeedsLayout;
         if (!needsLayout) {
             if (SVGElement* element = child->node()->isSVGElement() ? static_cast<SVGElement*>(child->node()) : 0) {
                 if (element->isStyled())
                     needsLayout = static_cast<SVGStyledElement*>(element)->hasRelativeValues();
             }
         }

         if (needsLayout)
             child->setNeedsLayout(true, false);

         child->layoutIfNeeded();
         ASSERT(!child->needsLayout());
     }
 }

 bool SVGRenderBase::isOverflowHidden(const RenderObject* object)
 {
     // SVG doesn't support independent x/y overflow
     ASSERT(object->style()->overflowX() == object->style()->overflowY());

     // OSCROLL is never set for SVG - see CSSStyleSelector::adjustRenderStyle
     ASSERT(object->style()->overflowX() != OSCROLL);

     // RenderSVGRoot should never query for overflow state - it should always clip itself to the initial viewport size.
     ASSERT(!object->isRoot());

     return object->style()->overflowX() == OHIDDEN;
 }

 FloatRect SVGRenderBase::filterBoundingBoxForRenderer(const RenderObject* object) const
 {
 #if ENABLE(FILTERS)
     if (RenderSVGResourceFilter* filter = getRenderSVGResourceById<RenderSVGResourceFilter>(object->document(), object->style()->svgStyle()->filterResource()))
         return filter->resourceBoundingBox(object->objectBoundingBox());
 #else
     UNUSED_PARAM(object);
 #endif
     return FloatRect();
 }

 FloatRect SVGRenderBase::clipperBoundingBoxForRenderer(const RenderObject* object) const
 {
     if (RenderSVGResourceClipper* clipper = getRenderSVGResourceById<RenderSVGResourceClipper>(object->document(), object->style()->svgStyle()->clipperResource()))
         return clipper->resourceBoundingBox(object->objectBoundingBox());

     return FloatRect();
 }

 FloatRect SVGRenderBase::maskerBoundingBoxForRenderer(const RenderObject* object) const
 {
     if (RenderSVGResourceMasker* masker = getRenderSVGResourceById<RenderSVGResourceMasker>(object->document(), object->style()->svgStyle()->maskerResource()))
         return masker->resourceBoundingBox(object->objectBoundingBox());

     return FloatRect();
 }

 static inline void invalidatePaintingResource(SVGPaint* paint, RenderObject* object)
 {
     ASSERT(paint);

     SVGPaint::SVGPaintType paintType = paint->paintType();
     if (paintType != SVGPaint::SVG_PAINTTYPE_URI && paintType != SVGPaint::SVG_PAINTTYPE_URI_RGBCOLOR)
         return;

     AtomicString id(SVGURIReference::getTarget(paint->uri()));
     if (RenderSVGResourceContainer* paintingResource = getRenderSVGResourceContainerById(object->document(), id))
         paintingResource->invalidateClient(object);
 }

 void deregisterFromResources(RenderObject* object)
 {
     ASSERT(object);
     ASSERT(object->style());

     Document* document = object->document();
     ASSERT(document);

     const SVGRenderStyle* svgStyle = object->style()->svgStyle();
     ASSERT(svgStyle);

     // Masker
     if (RenderSVGResourceMasker* masker = getRenderSVGResourceById<RenderSVGResourceMasker>(document, svgStyle->maskerResource()))
         masker->invalidateClient(object);

     // Clipper
     if (RenderSVGResourceClipper* clipper = getRenderSVGResourceById<RenderSVGResourceClipper>(document, svgStyle->clipperResource()))
         clipper->invalidateClient(object);

     // Filter
 #if ENABLE(FILTERS)
     if (RenderSVGResourceFilter* filter = getRenderSVGResourceById<RenderSVGResourceFilter>(document, svgStyle->filterResource()))
         filter->invalidateClient(object);
 #endif

     // Markers
     if (RenderSVGResourceMarker* startMarker = getRenderSVGResourceById<RenderSVGResourceMarker>(document, svgStyle->markerStartResource()))
         startMarker->invalidateClient(object);
     if (RenderSVGResourceMarker* midMarker = getRenderSVGResourceById<RenderSVGResourceMarker>(document, svgStyle->markerMidResource()))
         midMarker->invalidateClient(object);
     if (RenderSVGResourceMarker* endMarker = getRenderSVGResourceById<RenderSVGResourceMarker>(document, svgStyle->markerEndResource()))
         endMarker->invalidateClient(object);

     // Gradients/Patterns
     if (svgStyle->hasFill())
         invalidatePaintingResource(svgStyle->fillPaint(), object);
     if (svgStyle->hasStroke())
         invalidatePaintingResource(svgStyle->strokePaint(), object);
 }

 void applyTransformToPaintInfo(RenderObject::PaintInfo& paintInfo, const AffineTransform& localToAncestorTransform)
 {
     if (localToAncestorTransform.isIdentity())
         return;

     paintInfo.context->concatCTM(localToAncestorTransform);
     paintInfo.rect = localToAncestorTransform.inverse().mapRect(paintInfo.rect);
 }

 DashArray dashArrayFromRenderingStyle(const RenderStyle* style, RenderStyle* rootStyle)
 {
     DashArray array;

     CSSValueList* dashes = style->svgStyle()->strokeDashArray();
     if (dashes) {
         CSSPrimitiveValue* dash = 0;
         unsigned long len = dashes->length();
         for (unsigned long i = 0; i < len; i++) {
             dash = static_cast<CSSPrimitiveValue*>(dashes->itemWithoutBoundsCheck(i));
             if (!dash)
                 continue;

             array.append((float) dash->computeLengthFloat(const_cast<RenderStyle*>(style), rootStyle));
         }
     }

     return array;
 }

 void applyStrokeStyleToContext(GraphicsContext* context, const RenderStyle* style, const RenderObject* object)
 {
     context->setStrokeThickness(SVGRenderStyle::cssPrimitiveToLength(object, style->svgStyle()->strokeWidth(), 1.0f));
     context->setLineCap(style->svgStyle()->capStyle());
     context->setLineJoin(style->svgStyle()->joinStyle());
     if (style->svgStyle()->joinStyle() == MiterJoin)
         context->setMiterLimit(style->svgStyle()->strokeMiterLimit());

     const DashArray& dashes = dashArrayFromRenderingStyle(object->style(), object->document()->documentElement()->renderStyle());
     float dashOffset = SVGRenderStyle::cssPrimitiveToLength(object, style->svgStyle()->strokeDashOffset(), 0.0f);
     context->setLineDash(dashes, dashOffset);
 }

 const RenderObject* findTextRootObject(const RenderObject* start)
 {
     while (start && !start->isSVGText())
         start = start->parent();
     ASSERT(start);
     ASSERT(start->isSVGText());

     return start;
 }

 }

 #endif
	/*
	* Copyright (C) 2007, 2008 Rob Buis <buis@kde.org>
	* (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
	* (C) 2007 Eric Seidel <eric@webkit.org>
	* (C) 2009 Google, Inc. All rights reserved.
	* (C) 2009 Dirk Schulze <krit@webkit.org>
	* Copyright (C) Research In Motion Limited 2009-2010. 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"

	#if ENABLE(SVG)
	#include "SVGRenderSupport.h"

	#include "AffineTransform.h"
	#include "Document.h"
	#include "ImageBuffer.h"
	#include "NodeRenderStyle.h"
	#include "RenderObject.h"
	#include "RenderSVGContainer.h"
	#include "RenderSVGResource.h"
	#include "RenderSVGResourceClipper.h"
	#include "RenderSVGResourceFilter.h"
	#include "RenderSVGResourceMarker.h"
	#include "RenderSVGResourceMasker.h"
	#include "RenderView.h"
	#include "SVGStyledElement.h"
	#include "SVGURIReference.h"
	#include "TransformState.h"
	#include <wtf/UnusedParam.h>

	namespace WebCore {

	SVGRenderBase::~SVGRenderBase()
	{
	}

	IntRect SVGRenderBase::clippedOverflowRectForRepaint(RenderObject* object, RenderBoxModelObject* repaintContainer)
	{
	// Return early for any cases where we don't actually paint
	if (object->style()->visibility() != VISIBLE && !object->enclosingLayer()->hasVisibleContent())
	return IntRect();

	// Pass our local paint rect to computeRectForRepaint() which will
	// map to parent coords and recurse up the parent chain.
	IntRect repaintRect = enclosingIntRect(object->repaintRectInLocalCoordinates());
	object->computeRectForRepaint(repaintContainer, repaintRect);
	return repaintRect;
	}

	void SVGRenderBase::computeRectForRepaint(RenderObject* object, RenderBoxModelObject* repaintContainer, IntRect& repaintRect, bool fixed)
	{
	object->style()->svgStyle()->inflateForShadow(repaintRect);

	// Translate to coords in our parent renderer, and then call computeRectForRepaint on our parent
	repaintRect = object->localToParentTransform().mapRect(repaintRect);
	object->parent()->computeRectForRepaint(repaintContainer, repaintRect, fixed);
	}

	void SVGRenderBase::mapLocalToContainer(const RenderObject* object, RenderBoxModelObject* repaintContainer, bool fixed , bool useTransforms, TransformState& transformState)
	{
	ASSERT(!fixed); // We should have no fixed content in the SVG rendering tree.
	ASSERT(useTransforms); // Mapping a point through SVG w/o respecting transforms is useless.
	transformState.applyTransform(object->localToParentTransform());
	object->parent()->mapLocalToContainer(repaintContainer, fixed, useTransforms, transformState);
	}

	bool SVGRenderBase::prepareToRenderSVGContent(RenderObject* object, RenderObject::PaintInfo& paintInfo, const FloatRect& repaintRect, RenderSVGResourceFilter& filter, RenderSVGResourceFilter rootFilter)
	{
	#if !ENABLE(FILTERS)
	UNUSED_PARAM(filter);
	UNUSED_PARAM(rootFilter);
	#endif

	ASSERT(object);
	SVGElement* svgElement = static_cast<SVGElement*>(object->node());
	ASSERT(svgElement && svgElement->document() && svgElement->isStyled());

	SVGStyledElement* styledElement = static_cast<SVGStyledElement*>(svgElement);
	RenderStyle* style = object->style();
	ASSERT(style);

	const SVGRenderStyle* svgStyle = style->svgStyle();
	ASSERT(svgStyle);

	// Setup transparency layers before setting up filters!
	float opacity = style->opacity();
	if (opacity < 1.0f) {
	paintInfo.context->clip(repaintRect);
	paintInfo.context->beginTransparencyLayer(opacity);
	}

	if (const ShadowData* shadow = svgStyle->shadow()) {
	paintInfo.context->clip(repaintRect);
	paintInfo.context->setShadow(IntSize(shadow->x(), shadow->y()), shadow->blur(), shadow->color(), style->colorSpace());
	paintInfo.context->beginTransparencyLayer(1.0f);
	}

	#if ENABLE(FILTERS)
	AtomicString filterId(svgStyle->filterResource());
	#endif

	AtomicString clipperId(svgStyle->clipperResource());
	AtomicString maskerId(svgStyle->maskerResource());

	Document* document = object->document();

	#if ENABLE(FILTERS)
	RenderSVGResourceFilter* newFilter = getRenderSVGResourceById<RenderSVGResourceFilter>(document, filterId);
	if (newFilter == rootFilter) {
	// Catch <text filter="url(#foo)">Test<tspan filter="url(#foo)">123</tspan></text>.
	// The filter is NOT meant to be applied twice in that case!
	filter = 0;
	filterId = String();
	} else
	filter = newFilter;
	#endif

	if (RenderSVGResourceMasker* masker = getRenderSVGResourceById<RenderSVGResourceMasker>(document, maskerId)) {
	if (!masker->applyResource(object, style, paintInfo.context, ApplyToDefaultMode))
	return false;
	} else if (!maskerId.isEmpty())
	svgElement->document()->accessSVGExtensions()->addPendingResource(maskerId, styledElement);

	if (RenderSVGResourceClipper* clipper = getRenderSVGResourceById<RenderSVGResourceClipper>(document, clipperId))
	clipper->applyResource(object, style, paintInfo.context, ApplyToDefaultMode);
	else if (!clipperId.isEmpty())
	svgElement->document()->accessSVGExtensions()->addPendingResource(clipperId, styledElement);

	#if ENABLE(FILTERS)
	if (filter) {
	if (!filter->applyResource(object, style, paintInfo.context, ApplyToDefaultMode))
	return false;
	} else if (!filterId.isEmpty())
	svgElement->document()->accessSVGExtensions()->addPendingResource(filterId, styledElement);
	#endif

	return true;
	}

	void SVGRenderBase::finishRenderSVGContent(RenderObject* object, RenderObject::PaintInfo& paintInfo, RenderSVGResourceFilter& filter, GraphicsContext savedContext)
	{
	#if !ENABLE(FILTERS)
	UNUSED_PARAM(filter);
	UNUSED_PARAM(savedContext);
	#endif

	ASSERT(object);

	const RenderStyle* style = object->style();
	ASSERT(style);

	#if ENABLE(FILTERS)
	if (filter) {
	filter->postApplyResource(object, paintInfo.context, ApplyToDefaultMode);
	paintInfo.context = savedContext;
	}
	#endif

	float opacity = style->opacity();
	if (opacity < 1.0f)
	paintInfo.context->endTransparencyLayer();

	// This needs to be done separately from opacity, because if both properties are set,
	// then the transparency layers are nested.
	if (style->svgStyle()->shadow())
	paintInfo.context->endTransparencyLayer();
	}

	void renderSubtreeToImage(ImageBuffer* image, RenderObject* item)
	{
	ASSERT(item);
	ASSERT(image);
	ASSERT(image->context());

	// FIXME: This sets the rect to the viewable area of the current frame. This
	// is used to support text drawings to the ImageBuffer. See bug 30399.
	IntRect rect;
	FrameView* frameView = item->document()->view();
	if (frameView)
	rect = IntRect(0, 0, frameView->visibleWidth(), frameView->visibleHeight());
	RenderObject::PaintInfo info(image->context(), rect, PaintPhaseForeground, 0, 0, 0);

	// FIXME: isSVGContainer returns true for RenderSVGViewportContainer, so if this is ever
	// called with one of those, we will read from the wrong offset in an object due to a bad cast.
	RenderSVGContainer* svgContainer = 0;
	if (item && item->isSVGContainer())
	svgContainer = toRenderSVGContainer(item);

	bool drawsContents = svgContainer ? svgContainer->drawsContents() : false;
	if (svgContainer && !drawsContents)
	svgContainer->setDrawsContents(true);

	item->layoutIfNeeded();
	item->paint(info, 0, 0);

	if (svgContainer && !drawsContents)
	svgContainer->setDrawsContents(false);
	}

	void clampImageBufferSizeToViewport(FrameView* frameView, IntSize& size)
	{
	if (!frameView)
	return;

	int viewWidth = frameView->visibleWidth();
	int viewHeight = frameView->visibleHeight();

	if (size.width() > viewWidth)
	size.setWidth(viewWidth);

	if (size.height() > viewHeight)
	size.setHeight(viewHeight);
	}

	FloatRect SVGRenderBase::computeContainerBoundingBox(const RenderObject* container, bool includeAllPaintedContent)
	{
	FloatRect boundingBox;

	RenderObject* current = container->firstChild();
	for (; current != 0; current = current->nextSibling()) {
	FloatRect childBBox = includeAllPaintedContent ? current->repaintRectInLocalCoordinates() : current->objectBoundingBox();
	FloatRect childBBoxInLocalCoords = current->localToParentTransform().mapRect(childBBox);
	boundingBox.unite(childBBoxInLocalCoords);
	}

	return boundingBox;
	}

	void SVGRenderBase::layoutChildren(RenderObject* start, bool selfNeedsLayout)
	{
	for (RenderObject* child = start->firstChild(); child; child = child->nextSibling()) {
	// Only force our kids to layout if we're being asked to relayout as a result of a parent changing
	// FIXME: We should be able to skip relayout of non-relative kids when only bounds size has changed
	// that's a possible future optimization using LayoutState
	// http://bugs.webkit.org/show_bug.cgi?id=15391
	bool needsLayout = selfNeedsLayout;
	if (!needsLayout) {
	if (SVGElement* element = child->node()->isSVGElement() ? static_cast<SVGElement*>(child->node()) : 0) {
	if (element->isStyled())
	needsLayout = static_cast<SVGStyledElement*>(element)->hasRelativeValues();
	}
	}

	if (needsLayout)
	child->setNeedsLayout(true, false);

	child->layoutIfNeeded();
	ASSERT(!child->needsLayout());
	}
	}

	bool SVGRenderBase::isOverflowHidden(const RenderObject* object)
	{
	// SVG doesn't support independent x/y overflow
	ASSERT(object->style()->overflowX() == object->style()->overflowY());

	// OSCROLL is never set for SVG - see CSSStyleSelector::adjustRenderStyle
	ASSERT(object->style()->overflowX() != OSCROLL);

	// RenderSVGRoot should never query for overflow state - it should always clip itself to the initial viewport size.
	ASSERT(!object->isRoot());

	return object->style()->overflowX() == OHIDDEN;
	}

	FloatRect SVGRenderBase::filterBoundingBoxForRenderer(const RenderObject* object) const
	{
	#if ENABLE(FILTERS)
	if (RenderSVGResourceFilter* filter = getRenderSVGResourceById<RenderSVGResourceFilter>(object->document(), object->style()->svgStyle()->filterResource()))
	return filter->resourceBoundingBox(object->objectBoundingBox());
	#else
	UNUSED_PARAM(object);
	#endif
	return FloatRect();
	}

	FloatRect SVGRenderBase::clipperBoundingBoxForRenderer(const RenderObject* object) const
	{
	if (RenderSVGResourceClipper* clipper = getRenderSVGResourceById<RenderSVGResourceClipper>(object->document(), object->style()->svgStyle()->clipperResource()))
	return clipper->resourceBoundingBox(object->objectBoundingBox());

	return FloatRect();
	}

	FloatRect SVGRenderBase::maskerBoundingBoxForRenderer(const RenderObject* object) const
	{
	if (RenderSVGResourceMasker* masker = getRenderSVGResourceById<RenderSVGResourceMasker>(object->document(), object->style()->svgStyle()->maskerResource()))
	return masker->resourceBoundingBox(object->objectBoundingBox());

	return FloatRect();
	}

	static inline void invalidatePaintingResource(SVGPaint* paint, RenderObject* object)
	{
	ASSERT(paint);

	SVGPaint::SVGPaintType paintType = paint->paintType();
	if (paintType != SVGPaint::SVG_PAINTTYPE_URI && paintType != SVGPaint::SVG_PAINTTYPE_URI_RGBCOLOR)
	return;

	AtomicString id(SVGURIReference::getTarget(paint->uri()));
	if (RenderSVGResourceContainer* paintingResource = getRenderSVGResourceContainerById(object->document(), id))
	paintingResource->invalidateClient(object);
	}

	void deregisterFromResources(RenderObject* object)
	{
	ASSERT(object);
	ASSERT(object->style());

	Document* document = object->document();
	ASSERT(document);

	const SVGRenderStyle* svgStyle = object->style()->svgStyle();
	ASSERT(svgStyle);

	// Masker
	if (RenderSVGResourceMasker* masker = getRenderSVGResourceById<RenderSVGResourceMasker>(document, svgStyle->maskerResource()))
	masker->invalidateClient(object);

	// Clipper
	if (RenderSVGResourceClipper* clipper = getRenderSVGResourceById<RenderSVGResourceClipper>(document, svgStyle->clipperResource()))
	clipper->invalidateClient(object);

	// Filter
	#if ENABLE(FILTERS)
	if (RenderSVGResourceFilter* filter = getRenderSVGResourceById<RenderSVGResourceFilter>(document, svgStyle->filterResource()))
	filter->invalidateClient(object);
	#endif

	// Markers
	if (RenderSVGResourceMarker* startMarker = getRenderSVGResourceById<RenderSVGResourceMarker>(document, svgStyle->markerStartResource()))
	startMarker->invalidateClient(object);
	if (RenderSVGResourceMarker* midMarker = getRenderSVGResourceById<RenderSVGResourceMarker>(document, svgStyle->markerMidResource()))
	midMarker->invalidateClient(object);
	if (RenderSVGResourceMarker* endMarker = getRenderSVGResourceById<RenderSVGResourceMarker>(document, svgStyle->markerEndResource()))
	endMarker->invalidateClient(object);

	// Gradients/Patterns
	if (svgStyle->hasFill())
	invalidatePaintingResource(svgStyle->fillPaint(), object);
	if (svgStyle->hasStroke())
	invalidatePaintingResource(svgStyle->strokePaint(), object);
	}

	void applyTransformToPaintInfo(RenderObject::PaintInfo& paintInfo, const AffineTransform& localToAncestorTransform)
	{
	if (localToAncestorTransform.isIdentity())
	return;

	paintInfo.context->concatCTM(localToAncestorTransform);
	paintInfo.rect = localToAncestorTransform.inverse().mapRect(paintInfo.rect);
	}

	DashArray dashArrayFromRenderingStyle(const RenderStyle* style, RenderStyle* rootStyle)
	{
	DashArray array;

	CSSValueList* dashes = style->svgStyle()->strokeDashArray();
	if (dashes) {
	CSSPrimitiveValue* dash = 0;
	unsigned long len = dashes->length();
	for (unsigned long i = 0; i < len; i++) {
	dash = static_cast<CSSPrimitiveValue*>(dashes->itemWithoutBoundsCheck(i));
	if (!dash)
	continue;

	array.append((float) dash->computeLengthFloat(const_cast<RenderStyle*>(style), rootStyle));
	}
	}

	return array;
	}

	void applyStrokeStyleToContext(GraphicsContext* context, const RenderStyle* style, const RenderObject* object)
	{
	context->setStrokeThickness(SVGRenderStyle::cssPrimitiveToLength(object, style->svgStyle()->strokeWidth(), 1.0f));
	context->setLineCap(style->svgStyle()->capStyle());
	context->setLineJoin(style->svgStyle()->joinStyle());
	if (style->svgStyle()->joinStyle() == MiterJoin)
	context->setMiterLimit(style->svgStyle()->strokeMiterLimit());

	const DashArray& dashes = dashArrayFromRenderingStyle(object->style(), object->document()->documentElement()->renderStyle());
	float dashOffset = SVGRenderStyle::cssPrimitiveToLength(object, style->svgStyle()->strokeDashOffset(), 0.0f);
	context->setLineDash(dashes, dashOffset);
	}

	const RenderObject* findTextRootObject(const RenderObject* start)
	{
	while (start && !start->isSVGText())
	start = start->parent();
	ASSERT(start);
	ASSERT(start->isSVGText());

	return start;
	}

	}

	#endif