| /* |
| * 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 "core/SVGNames.h" |
| #include "core/dom/ElementTraversal.h" |
| #include "core/frame/FrameView.h" |
| #include "core/frame/LocalFrame.h" |
| #include "core/rendering/HitTestResult.h" |
| #include "core/rendering/svg/SVGRenderSupport.h" |
| #include "core/rendering/svg/SVGRenderingContext.h" |
| #include "core/rendering/svg/SVGResources.h" |
| #include "core/rendering/svg/SVGResourcesCache.h" |
| #include "core/svg/SVGUseElement.h" |
| #include "platform/RuntimeEnabledFeatures.h" |
| #include "platform/graphics/DisplayList.h" |
| #include "platform/graphics/GraphicsContextStateSaver.h" |
| #include "wtf/TemporaryChange.h" |
| |
| namespace blink { |
| |
| const RenderSVGResourceType RenderSVGResourceClipper::s_resourceType = ClipperResourceType; |
| |
| RenderSVGResourceClipper::RenderSVGResourceClipper(SVGClipPathElement* node) |
| : RenderSVGResourceContainer(node) |
| , m_inClipExpansion(false) |
| { |
| } |
| |
| RenderSVGResourceClipper::~RenderSVGResourceClipper() |
| { |
| } |
| |
| void RenderSVGResourceClipper::removeAllClientsFromCache(bool markForInvalidation) |
| { |
| m_clipContentDisplayList.clear(); |
| m_clipBoundaries = FloatRect(); |
| markAllClientsForInvalidation(markForInvalidation ? LayoutAndBoundariesInvalidation : ParentOnlyInvalidation); |
| } |
| |
| void RenderSVGResourceClipper::removeClientFromCache(RenderObject* client, bool markForInvalidation) |
| { |
| ASSERT(client); |
| markClientForInvalidation(client, markForInvalidation ? BoundariesInvalidation : ParentOnlyInvalidation); |
| } |
| |
| bool RenderSVGResourceClipper::applyResource(RenderObject*, RenderStyle*, GraphicsContext*&, unsigned short) |
| { |
| // Clippers are always applied using stateful methods. |
| ASSERT_NOT_REACHED(); |
| return false; |
| } |
| |
| bool RenderSVGResourceClipper::applyStatefulResource(RenderObject* object, GraphicsContext*& context, ClipperState& clipperState) |
| { |
| ASSERT(object); |
| ASSERT(context); |
| |
| clearInvalidationMask(); |
| |
| return applyClippingToContext(object, object->objectBoundingBox(), object->paintInvalidationRectInLocalCoordinates(), context, clipperState); |
| } |
| |
| bool RenderSVGResourceClipper::tryPathOnlyClipping(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 (SVGElement* childElement = Traversal<SVGElement>::firstChild(*element()); childElement; childElement = Traversal<SVGElement>::nextSibling(*childElement)) { |
| RenderObject* renderer = childElement->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 (!childElement->isSVGGraphicsElement()) |
| continue; |
| SVGGraphicsElement* styled = toSVGGraphicsElement(childElement); |
| 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 (clipPathUnits() == 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* target, const FloatRect& targetBoundingBox, |
| const FloatRect& paintInvalidationRect, GraphicsContext* context, ClipperState& clipperState) |
| { |
| ASSERT(target); |
| ASSERT(context); |
| ASSERT(clipperState == ClipperNotApplied); |
| ASSERT_WITH_SECURITY_IMPLICATION(!needsLayout()); |
| |
| if (paintInvalidationRect.isEmpty() || m_inClipExpansion) |
| return false; |
| TemporaryChange<bool> inClipExpansionChange(m_inClipExpansion, true); |
| |
| AffineTransform animatedLocalTransform = toSVGClipPathElement(element())->animatedLocalTransform(); |
| // When drawing a clip for non-SVG elements, the CTM does not include the zoom factor. |
| // In this case, we need to apply the zoom scale explicitly - but only for clips with |
| // userSpaceOnUse units (the zoom is accounted for objectBoundingBox-resolved lengths). |
| if (!target->isSVG() && clipPathUnits() == SVGUnitTypes::SVG_UNIT_TYPE_USERSPACEONUSE) { |
| ASSERT(style()); |
| animatedLocalTransform.scale(style()->effectiveZoom()); |
| } |
| |
| // First, try to apply the clip as a clipPath. |
| if (tryPathOnlyClipping(context, animatedLocalTransform, targetBoundingBox)) { |
| clipperState = ClipperAppliedPath; |
| return true; |
| } |
| |
| // Fall back to masking. |
| clipperState = ClipperAppliedMask; |
| |
| // Mask layer start |
| context->beginTransparencyLayer(1, &paintInvalidationRect); |
| { |
| GraphicsContextStateSaver maskContentSaver(*context); |
| context->concatCTM(animatedLocalTransform); |
| |
| // clipPath can also be clipped by another clipPath. |
| SVGResources* resources = SVGResourcesCache::cachedResourcesForRenderObject(this); |
| RenderSVGResourceClipper* clipPathClipper = resources ? resources->clipper() : 0; |
| ClipperState clipPathClipperState = ClipperNotApplied; |
| if (clipPathClipper && !clipPathClipper->applyClippingToContext(this, targetBoundingBox, paintInvalidationRect, context, clipPathClipperState)) { |
| // FIXME: Awkward state micro-management. Ideally, GraphicsContextStateSaver should |
| // a) pop saveLayers also |
| // b) pop multiple states if needed (similarly to SkCanvas::restoreToCount()) |
| // Then we should be able to replace this mess with a single, top-level GCSS. |
| maskContentSaver.restore(); |
| context->restoreLayer(); |
| return false; |
| } |
| |
| drawClipMaskContent(context, targetBoundingBox); |
| |
| if (clipPathClipper) |
| clipPathClipper->postApplyStatefulResource(this, context, clipPathClipperState); |
| } |
| |
| // Masked content layer start. |
| context->beginLayer(1, CompositeSourceIn, &paintInvalidationRect); |
| |
| return true; |
| } |
| |
| void RenderSVGResourceClipper::postApplyResource(RenderObject*, GraphicsContext*&, unsigned short, |
| const Path*, const RenderSVGShape*) { |
| // Clippers are always applied using stateful methods. |
| ASSERT_NOT_REACHED(); |
| } |
| |
| void RenderSVGResourceClipper::postApplyStatefulResource(RenderObject*, GraphicsContext*& context, ClipperState& clipperState) |
| { |
| switch (clipperState) { |
| case ClipperAppliedPath: |
| // Path-only clipping, no layers to restore. |
| break; |
| case ClipperAppliedMask: |
| // Transfer content layer -> mask layer (SrcIn) |
| context->endLayer(); |
| // Transfer mask layer -> bg layer (SrcOver) |
| context->endLayer(); |
| break; |
| default: |
| ASSERT_NOT_REACHED(); |
| } |
| } |
| |
| void RenderSVGResourceClipper::drawClipMaskContent(GraphicsContext* context, const FloatRect& targetBoundingBox) |
| { |
| ASSERT(context); |
| |
| AffineTransform contentTransformation; |
| if (clipPathUnits() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) { |
| contentTransformation.translate(targetBoundingBox.x(), targetBoundingBox.y()); |
| contentTransformation.scaleNonUniform(targetBoundingBox.width(), targetBoundingBox.height()); |
| context->concatCTM(contentTransformation); |
| } |
| |
| if (!m_clipContentDisplayList) |
| createDisplayList(context, contentTransformation); |
| |
| ASSERT(m_clipContentDisplayList); |
| context->drawDisplayList(m_clipContentDisplayList.get()); |
| } |
| |
| void RenderSVGResourceClipper::createDisplayList(GraphicsContext* context, |
| const AffineTransform& contentTransformation) |
| { |
| ASSERT(context); |
| ASSERT(frame()); |
| |
| // Using strokeBoundingBox (instead of paintInvalidationRectInLocalCoordinates) to avoid the intersection |
| // with local clips/mask, which may yield incorrect results when mixing objectBoundingBox and |
| // userSpaceOnUse units (http://crbug.com/294900). |
| FloatRect bounds = strokeBoundingBox(); |
| context->beginRecording(bounds); |
| |
| // 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); |
| |
| for (SVGElement* childElement = Traversal<SVGElement>::firstChild(*element()); childElement; childElement = Traversal<SVGElement>::nextSibling(*childElement)) { |
| RenderObject* renderer = childElement->renderer(); |
| if (!renderer) |
| continue; |
| |
| RenderStyle* style = renderer->style(); |
| if (!style || style->display() == NONE || style->visibility() != VISIBLE) |
| continue; |
| |
| WindRule newClipRule = style->svgStyle().clipRule(); |
| bool isUseElement = isSVGUseElement(*childElement); |
| if (isUseElement) { |
| SVGUseElement& useElement = toSVGUseElement(*childElement); |
| 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; |
| |
| context->setFillRule(newClipRule); |
| |
| if (isUseElement) |
| renderer = childElement->renderer(); |
| |
| SVGRenderingContext::renderSubtree(context, renderer, contentTransformation); |
| } |
| |
| frame()->view()->setPaintBehavior(oldBehavior); |
| |
| m_clipContentDisplayList = context->endRecording(); |
| } |
| |
| void RenderSVGResourceClipper::calculateClipContentPaintInvalidationRect() |
| { |
| // This is a rough heuristic to appraise the clip size and doesn't consider clip on clip. |
| for (SVGElement* childElement = Traversal<SVGElement>::firstChild(*element()); childElement; childElement = Traversal<SVGElement>::nextSibling(*childElement)) { |
| RenderObject* renderer = childElement->renderer(); |
| if (!renderer) |
| continue; |
| if (!renderer->isSVGShape() && !renderer->isSVGText() && !isSVGUseElement(*childElement)) |
| continue; |
| RenderStyle* style = renderer->style(); |
| if (!style || style->display() == NONE || style->visibility() != VISIBLE) |
| continue; |
| m_clipBoundaries.unite(renderer->localToParentTransform().mapRect(renderer->paintInvalidationRectInLocalCoordinates())); |
| } |
| m_clipBoundaries = toSVGClipPathElement(element())->animatedLocalTransform().mapRect(m_clipBoundaries); |
| } |
| |
| bool RenderSVGResourceClipper::hitTestClipContent(const FloatRect& objectBoundingBox, const FloatPoint& nodeAtPoint) |
| { |
| FloatPoint point = nodeAtPoint; |
| if (!SVGRenderSupport::pointInClippingArea(this, point)) |
| return false; |
| |
| if (clipPathUnits() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) { |
| AffineTransform transform; |
| transform.translate(objectBoundingBox.x(), objectBoundingBox.y()); |
| transform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height()); |
| point = transform.inverse().mapPoint(point); |
| } |
| |
| AffineTransform animatedLocalTransform = toSVGClipPathElement(element())->animatedLocalTransform(); |
| if (!animatedLocalTransform.isInvertible()) |
| return false; |
| |
| point = animatedLocalTransform.inverse().mapPoint(point); |
| |
| for (SVGElement* childElement = Traversal<SVGElement>::firstChild(*element()); childElement; childElement = Traversal<SVGElement>::nextSibling(*childElement)) { |
| RenderObject* renderer = childElement->renderer(); |
| if (!renderer) |
| continue; |
| if (!renderer->isSVGShape() && !renderer->isSVGText() && !isSVGUseElement(*childElement)) |
| continue; |
| IntPoint hitPoint; |
| HitTestResult result(hitPoint); |
| if (renderer->nodeAtFloatPoint(HitTestRequest(HitTestRequest::SVGClipContent), result, point, HitTestForeground)) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| FloatRect RenderSVGResourceClipper::resourceBoundingBox(const RenderObject* object) |
| { |
| // Resource was not layouted yet. Give back the boundingBox of the object. |
| if (selfNeedsLayout()) |
| return object->objectBoundingBox(); |
| |
| if (m_clipBoundaries.isEmpty()) |
| calculateClipContentPaintInvalidationRect(); |
| |
| if (clipPathUnits() == 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; |
| } |
| |
| } |
