blob: 9da09f9d9f0c299df32978dd0d74385de5bcab12 [file] [log] [blame]
/*
* Copyright (C) 2004, 2005, 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
* Copyright (C) 2004, 2005, 2006, 2007, 2008 Rob Buis <buis@kde.org>
* Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
* Copyright (C) 2011 Dirk Schulze <krit@webkit.org>
*
* 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 "core/rendering/svg/RenderSVGResourceClipper.h"
#include "RuntimeEnabledFeatures.h"
#include "SVGNames.h"
#include "core/page/FrameView.h"
#include "core/platform/graphics/GraphicsContextStateSaver.h"
#include "core/rendering/HitTestResult.h"
#include "core/rendering/svg/SVGRenderingContext.h"
#include "core/rendering/svg/SVGResources.h"
#include "core/rendering/svg/SVGResourcesCache.h"
#include "core/svg/SVGUseElement.h"
namespace WebCore {
RenderSVGResourceType RenderSVGResourceClipper::s_resourceType = ClipperResourceType;
RenderSVGResourceClipper::RenderSVGResourceClipper(SVGClipPathElement* node)
: RenderSVGResourceContainer(node)
{
}
RenderSVGResourceClipper::~RenderSVGResourceClipper()
{
if (m_clipper.isEmpty())
return;
deleteAllValues(m_clipper);
m_clipper.clear();
}
void RenderSVGResourceClipper::removeAllClientsFromCache(bool markForInvalidation)
{
m_clipBoundaries = FloatRect();
if (!m_clipper.isEmpty()) {
deleteAllValues(m_clipper);
m_clipper.clear();
}
markAllClientsForInvalidation(markForInvalidation ? LayoutAndBoundariesInvalidation : ParentOnlyInvalidation);
}
void RenderSVGResourceClipper::removeClientFromCache(RenderObject* client, bool markForInvalidation)
{
ASSERT(client);
if (m_clipper.contains(client))
delete m_clipper.take(client);
markClientForInvalidation(client, markForInvalidation ? BoundariesInvalidation : ParentOnlyInvalidation);
}
bool RenderSVGResourceClipper::applyResource(RenderObject* object, RenderStyle*, GraphicsContext*& context, unsigned short resourceMode)
{
ASSERT(object);
ASSERT(context);
ASSERT_UNUSED(resourceMode, resourceMode == ApplyToDefaultMode);
return applyClippingToContext(object, object->objectBoundingBox(), object->repaintRectInLocalCoordinates(), context);
}
bool RenderSVGResourceClipper::pathOnlyClipping(GraphicsContext* context, const AffineTransform& animatedLocalTransform, const FloatRect& objectBoundingBox)
{
// If the current clip-path gets clipped itself, we have to fallback to masking.
if (!style()->svgStyle()->clipperResource().isEmpty())
return false;
WindRule clipRule = RULE_NONZERO;
Path clipPath = Path();
for (Node* childNode = node()->firstChild(); childNode; childNode = childNode->nextSibling()) {
RenderObject* renderer = childNode->renderer();
if (!renderer)
continue;
// Only shapes or paths are supported for direct clipping. We need to fallback to masking for texts.
if (renderer->isSVGText())
return false;
if (!childNode->isSVGElement() || !toSVGElement(childNode)->isSVGGraphicsElement())
continue;
SVGGraphicsElement* styled = toSVGGraphicsElement(childNode);
RenderStyle* style = renderer->style();
if (!style || style->display() == NONE || style->visibility() != VISIBLE)
continue;
const SVGRenderStyle* svgStyle = style->svgStyle();
// Current shape in clip-path gets clipped too. Fallback to masking.
if (!svgStyle->clipperResource().isEmpty())
return false;
if (clipPath.isEmpty()) {
// First clip shape.
styled->toClipPath(clipPath);
clipRule = svgStyle->clipRule();
clipPath.setWindRule(clipRule);
continue;
}
if (RuntimeEnabledFeatures::pathOpsSVGClippingEnabled()) {
// Attempt to generate a combined clip path, fall back to masking if not possible.
Path subPath;
styled->toClipPath(subPath);
subPath.setWindRule(svgStyle->clipRule());
if (!clipPath.unionPath(subPath))
return false;
} else {
return false;
}
}
// Only one visible shape/path was found. Directly continue clipping and transform the content to userspace if necessary.
if (toSVGClipPathElement(node())->clipPathUnitsCurrentValue() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
AffineTransform transform;
transform.translate(objectBoundingBox.x(), objectBoundingBox.y());
transform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
clipPath.transform(transform);
}
// Transform path by animatedLocalTransform.
clipPath.transform(animatedLocalTransform);
// The SVG specification wants us to clip everything, if clip-path doesn't have a child.
if (clipPath.isEmpty())
clipPath.addRect(FloatRect());
context->clipPath(clipPath, clipRule);
return true;
}
bool RenderSVGResourceClipper::applyClippingToContext(RenderObject* object, const FloatRect& objectBoundingBox,
const FloatRect& repaintRect, GraphicsContext* context)
{
bool missingClipperData = !m_clipper.contains(object);
if (missingClipperData)
m_clipper.set(object, new ClipperData);
bool shouldCreateClipData = false;
AffineTransform animatedLocalTransform = toSVGClipPathElement(node())->animatedLocalTransform();
ClipperData* clipperData = m_clipper.get(object);
if (!clipperData->clipMaskImage) {
if (pathOnlyClipping(context, animatedLocalTransform, objectBoundingBox))
return true;
shouldCreateClipData = true;
}
AffineTransform absoluteTransform;
SVGRenderingContext::calculateTransformationToOutermostCoordinateSystem(object, absoluteTransform);
if (shouldCreateClipData && !repaintRect.isEmpty()) {
if (!SVGRenderingContext::createImageBuffer(repaintRect, absoluteTransform, clipperData->clipMaskImage, Unaccelerated))
return false;
GraphicsContext* maskContext = clipperData->clipMaskImage->context();
ASSERT(maskContext);
maskContext->concatCTM(animatedLocalTransform);
// clipPath can also be clipped by another clipPath.
SVGResources* resources = SVGResourcesCache::cachedResourcesForRenderObject(this);
RenderSVGResourceClipper* clipper;
bool succeeded;
if (resources && (clipper = resources->clipper())) {
GraphicsContextStateSaver stateSaver(*maskContext);
if (!clipper->applyClippingToContext(this, objectBoundingBox, repaintRect, maskContext))
return false;
succeeded = drawContentIntoMaskImage(clipperData, objectBoundingBox);
// The context restore applies the clipping on non-CG platforms.
} else
succeeded = drawContentIntoMaskImage(clipperData, objectBoundingBox);
if (!succeeded)
clipperData->clipMaskImage.clear();
}
if (!clipperData->clipMaskImage)
return false;
SVGRenderingContext::clipToImageBuffer(context, absoluteTransform, repaintRect, clipperData->clipMaskImage, missingClipperData);
return true;
}
bool RenderSVGResourceClipper::drawContentIntoMaskImage(ClipperData* clipperData, const FloatRect& objectBoundingBox)
{
ASSERT(frame());
ASSERT(clipperData);
ASSERT(clipperData->clipMaskImage);
GraphicsContext* maskContext = clipperData->clipMaskImage->context();
ASSERT(maskContext);
AffineTransform maskContentTransformation;
if (toSVGClipPathElement(node())->clipPathUnitsCurrentValue() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
maskContentTransformation.translate(objectBoundingBox.x(), objectBoundingBox.y());
maskContentTransformation.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
maskContext->concatCTM(maskContentTransformation);
}
// Switch to a paint behavior where all children of this <clipPath> will be rendered using special constraints:
// - fill-opacity/stroke-opacity/opacity set to 1
// - masker/filter not applied when rendering the children
// - fill is set to the initial fill paint server (solid, black)
// - stroke is set to the initial stroke paint server (none)
PaintBehavior oldBehavior = frame()->view()->paintBehavior();
frame()->view()->setPaintBehavior(oldBehavior | PaintBehaviorRenderingSVGMask);
// Draw all clipPath children into a global mask.
for (Node* childNode = node()->firstChild(); childNode; childNode = childNode->nextSibling()) {
RenderObject* renderer = childNode->renderer();
if (!childNode->isSVGElement() || !renderer)
continue;
if (renderer->needsLayout()) {
frame()->view()->setPaintBehavior(oldBehavior);
return false;
}
RenderStyle* style = renderer->style();
if (!style || style->display() == NONE || style->visibility() != VISIBLE)
continue;
WindRule newClipRule = style->svgStyle()->clipRule();
bool isUseElement = childNode->hasTagName(SVGNames::useTag);
if (isUseElement) {
SVGUseElement* useElement = toSVGUseElement(childNode);
renderer = useElement->rendererClipChild();
if (!renderer)
continue;
if (!useElement->hasAttribute(SVGNames::clip_ruleAttr))
newClipRule = renderer->style()->svgStyle()->clipRule();
}
// Only shapes, paths and texts are allowed for clipping.
if (!renderer->isSVGShape() && !renderer->isSVGText())
continue;
maskContext->setFillRule(newClipRule);
// In the case of a <use> element, we obtained its renderere above, to retrieve its clipRule.
// We have to pass the <use> renderer itself to renderSubtreeToImageBuffer() to apply it's x/y/transform/etc. values when rendering.
// So if isUseElement is true, refetch the childNode->renderer(), as renderer got overriden above.
SVGRenderingContext::renderSubtreeToImageBuffer(clipperData->clipMaskImage.get(), isUseElement ? childNode->renderer() : renderer, maskContentTransformation);
}
frame()->view()->setPaintBehavior(oldBehavior);
return true;
}
void RenderSVGResourceClipper::calculateClipContentRepaintRect()
{
// This is a rough heuristic to appraise the clip size and doesn't consider clip on clip.
for (Node* childNode = node()->firstChild(); childNode; childNode = childNode->nextSibling()) {
RenderObject* renderer = childNode->renderer();
if (!childNode->isSVGElement() || !renderer)
continue;
if (!renderer->isSVGShape() && !renderer->isSVGText() && !childNode->hasTagName(SVGNames::useTag))
continue;
RenderStyle* style = renderer->style();
if (!style || style->display() == NONE || style->visibility() != VISIBLE)
continue;
m_clipBoundaries.unite(renderer->localToParentTransform().mapRect(renderer->repaintRectInLocalCoordinates()));
}
m_clipBoundaries = toSVGClipPathElement(node())->animatedLocalTransform().mapRect(m_clipBoundaries);
}
bool RenderSVGResourceClipper::hitTestClipContent(const FloatRect& objectBoundingBox, const FloatPoint& nodeAtPoint)
{
FloatPoint point = nodeAtPoint;
if (!SVGRenderSupport::pointInClippingArea(this, point))
return false;
SVGClipPathElement* clipPathElement = toSVGClipPathElement(node());
if (clipPathElement->clipPathUnitsCurrentValue() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
AffineTransform transform;
transform.translate(objectBoundingBox.x(), objectBoundingBox.y());
transform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
point = transform.inverse().mapPoint(point);
}
point = clipPathElement->animatedLocalTransform().inverse().mapPoint(point);
for (Node* childNode = node()->firstChild(); childNode; childNode = childNode->nextSibling()) {
RenderObject* renderer = childNode->renderer();
if (!childNode->isSVGElement() || !renderer)
continue;
if (!renderer->isSVGShape() && !renderer->isSVGText() && !childNode->hasTagName(SVGNames::useTag))
continue;
IntPoint hitPoint;
HitTestResult result(hitPoint);
if (renderer->nodeAtFloatPoint(HitTestRequest(HitTestRequest::SVGClipContent | HitTestRequest::DisallowShadowContent), result, point, HitTestForeground))
return true;
}
return false;
}
FloatRect RenderSVGResourceClipper::resourceBoundingBox(RenderObject* object)
{
// Resource was not layouted yet. Give back the boundingBox of the object.
if (selfNeedsLayout())
return object->objectBoundingBox();
if (m_clipBoundaries.isEmpty())
calculateClipContentRepaintRect();
if (toSVGClipPathElement(node())->clipPathUnitsCurrentValue() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
FloatRect objectBoundingBox = object->objectBoundingBox();
AffineTransform transform;
transform.translate(objectBoundingBox.x(), objectBoundingBox.y());
transform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
return transform.mapRect(m_clipBoundaries);
}
return m_clipBoundaries;
}
}