--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/rendering/RenderLayerCompositor.cpp Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,1487 @@
+/*
+ * Copyright (C) 2009, 2010 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+
+#if USE(ACCELERATED_COMPOSITING)
+#include "RenderLayerCompositor.h"
+
+#include "AnimationController.h"
+#include "CSSPropertyNames.h"
+#include "Chrome.h"
+#include "ChromeClient.h"
+#include "Frame.h"
+#include "FrameView.h"
+#include "GraphicsLayer.h"
+#include "HTMLCanvasElement.h"
+#include "HTMLIFrameElement.h"
+#include "HTMLNames.h"
+#include "HitTestResult.h"
+#include "NodeList.h"
+#include "Page.h"
+#include "RenderEmbeddedObject.h"
+#include "RenderIFrame.h"
+#include "RenderLayerBacking.h"
+#include "RenderReplica.h"
+#include "RenderVideo.h"
+#include "RenderView.h"
+#include "Settings.h"
+
+#if ENABLE(PLUGIN_PROXY_FOR_VIDEO)
+#include "HTMLMediaElement.h"
+#endif
+
+#if PROFILE_LAYER_REBUILD
+#include <wtf/CurrentTime.h>
+#endif
+
+#ifndef NDEBUG
+#include "RenderTreeAsText.h"
+#endif
+
+#if ENABLE(3D_RENDERING)
+// This symbol is used to determine from a script whether 3D rendering is enabled (via 'nm').
+bool WebCoreHas3DRendering = true;
+#endif
+
+namespace WebCore {
+
+using namespace HTMLNames;
+
+struct CompositingState {
+ CompositingState(RenderLayer* compAncestor)
+ : m_compositingAncestor(compAncestor)
+ , m_subtreeIsCompositing(false)
+#ifndef NDEBUG
+ , m_depth(0)
+#endif
+ {
+ }
+
+ RenderLayer* m_compositingAncestor;
+ bool m_subtreeIsCompositing;
+#ifndef NDEBUG
+ int m_depth;
+#endif
+};
+
+RenderLayerCompositor::RenderLayerCompositor(RenderView* renderView)
+ : m_renderView(renderView)
+ , m_rootPlatformLayer(0)
+ , m_hasAcceleratedCompositing(true)
+ , m_showDebugBorders(false)
+ , m_showRepaintCounter(false)
+ , m_compositingConsultsOverlap(true)
+ , m_compositingDependsOnGeometry(false)
+ , m_compositing(false)
+ , m_compositingLayersNeedRebuild(false)
+ , m_rootLayerAttachment(RootLayerUnattached)
+#if PROFILE_LAYER_REBUILD
+ , m_rootLayerUpdateCount(0)
+#endif // PROFILE_LAYER_REBUILD
+{
+}
+
+RenderLayerCompositor::~RenderLayerCompositor()
+{
+ ASSERT(m_rootLayerAttachment == RootLayerUnattached);
+}
+
+void RenderLayerCompositor::enableCompositingMode(bool enable /* = true */)
+{
+ if (enable != m_compositing) {
+ m_compositing = enable;
+
+ if (m_compositing) {
+ ensureRootPlatformLayer();
+ notifyIFramesOfCompositingChange();
+ } else
+ destroyRootPlatformLayer();
+ }
+}
+
+void RenderLayerCompositor::cacheAcceleratedCompositingFlags()
+{
+ bool hasAcceleratedCompositing = false;
+ bool showDebugBorders = false;
+ bool showRepaintCounter = false;
+
+ if (Settings* settings = m_renderView->document()->settings()) {
+ hasAcceleratedCompositing = settings->acceleratedCompositingEnabled();
+ showDebugBorders = settings->showDebugBorders();
+ showRepaintCounter = settings->showRepaintCounter();
+ }
+
+ // We allow the chrome to override the settings, in case the page is rendered
+ // on a chrome that doesn't allow accelerated compositing.
+ if (hasAcceleratedCompositing) {
+ Frame* frame = m_renderView->frameView()->frame();
+ Page* page = frame ? frame->page() : 0;
+ if (page)
+ hasAcceleratedCompositing = page->chrome()->client()->allowsAcceleratedCompositing();
+ }
+
+ if (hasAcceleratedCompositing != m_hasAcceleratedCompositing || showDebugBorders != m_showDebugBorders || showRepaintCounter != m_showRepaintCounter)
+ setCompositingLayersNeedRebuild();
+
+ m_hasAcceleratedCompositing = hasAcceleratedCompositing;
+ m_showDebugBorders = showDebugBorders;
+ m_showRepaintCounter = showRepaintCounter;
+}
+
+void RenderLayerCompositor::setCompositingLayersNeedRebuild(bool needRebuild)
+{
+ if (inCompositingMode())
+ m_compositingLayersNeedRebuild = needRebuild;
+}
+
+void RenderLayerCompositor::scheduleSync()
+{
+ Frame* frame = m_renderView->frameView()->frame();
+ Page* page = frame ? frame->page() : 0;
+ if (!page)
+ return;
+
+ page->chrome()->client()->scheduleCompositingLayerSync();
+}
+
+void RenderLayerCompositor::updateCompositingLayers(CompositingUpdateType updateType, RenderLayer* updateRoot)
+{
+ if (!m_compositingDependsOnGeometry && !m_compositing)
+ return;
+
+ bool checkForHierarchyUpdate = m_compositingDependsOnGeometry;
+ bool needGeometryUpdate = false;
+
+ switch (updateType) {
+ case CompositingUpdateAfterLayoutOrStyleChange:
+ case CompositingUpdateOnPaitingOrHitTest:
+ checkForHierarchyUpdate = true;
+ break;
+ case CompositingUpdateOnScroll:
+ if (m_compositingConsultsOverlap)
+ checkForHierarchyUpdate = true; // Overlap can change with scrolling, so need to check for hierarchy updates.
+
+ needGeometryUpdate = true;
+ break;
+ }
+
+ if (!checkForHierarchyUpdate && !needGeometryUpdate)
+ return;
+
+ bool needHierarchyUpdate = m_compositingLayersNeedRebuild;
+ if (!updateRoot) {
+ // Only clear the flag if we're updating the entire hierarchy.
+ m_compositingLayersNeedRebuild = false;
+ updateRoot = rootRenderLayer();
+ }
+
+#if PROFILE_LAYER_REBUILD
+ ++m_rootLayerUpdateCount;
+
+ double startTime = WTF::currentTime();
+#endif
+
+ if (checkForHierarchyUpdate) {
+ // Go through the layers in presentation order, so that we can compute which RenderLayers need compositing layers.
+ // FIXME: we could maybe do this and the hierarchy udpate in one pass, but the parenting logic would be more complex.
+ CompositingState compState(updateRoot);
+ bool layersChanged = false;
+ if (m_compositingConsultsOverlap) {
+ OverlapMap overlapTestRequestMap;
+ computeCompositingRequirements(updateRoot, &overlapTestRequestMap, compState, layersChanged);
+ } else
+ computeCompositingRequirements(updateRoot, 0, compState, layersChanged);
+
+ needHierarchyUpdate |= layersChanged;
+ }
+
+ if (needHierarchyUpdate) {
+ // Update the hierarchy of the compositing layers.
+ CompositingState compState(updateRoot);
+ Vector<GraphicsLayer*> childList;
+ rebuildCompositingLayerTree(updateRoot, compState, childList);
+
+ // Host the document layer in the RenderView's root layer.
+ if (updateRoot == rootRenderLayer()) {
+ if (childList.isEmpty())
+ destroyRootPlatformLayer();
+ else
+ m_rootPlatformLayer->setChildren(childList);
+ }
+ } else if (needGeometryUpdate) {
+ // We just need to do a geometry update. This is only used for position:fixed scrolling;
+ // most of the time, geometry is updated via RenderLayer::styleChanged().
+ updateLayerTreeGeometry(updateRoot);
+ }
+
+#if PROFILE_LAYER_REBUILD
+ double endTime = WTF::currentTime();
+ if (updateRoot == rootRenderLayer())
+ fprintf(stderr, "Update %d: computeCompositingRequirements for the world took %fms\n",
+ m_rootLayerUpdateCount, 1000.0 * (endTime - startTime));
+#endif
+ ASSERT(updateRoot || !m_compositingLayersNeedRebuild);
+
+ if (!hasAcceleratedCompositing())
+ enableCompositingMode(false);
+}
+
+bool RenderLayerCompositor::updateBacking(RenderLayer* layer, CompositingChangeRepaint shouldRepaint)
+{
+ bool layerChanged = false;
+
+ if (needsToBeComposited(layer)) {
+ enableCompositingMode();
+
+ // 3D transforms turn off the testing of overlap.
+ if (requiresCompositingForTransform(layer->renderer()))
+ setCompositingConsultsOverlap(false);
+
+ if (!layer->backing()) {
+
+ // If we need to repaint, do so before making backing
+ if (shouldRepaint == CompositingChangeRepaintNow)
+ repaintOnCompositingChange(layer);
+
+ layer->ensureBacking();
+ layerChanged = true;
+ }
+ } else {
+ if (layer->backing()) {
+ // If we're removing backing on a reflection, clear the source GraphicsLayer's pointer to
+ // its replica GraphicsLayer. In practice this should never happen because reflectee and reflection
+ // are both either composited, or not composited.
+ if (layer->isReflection()) {
+ RenderLayer* sourceLayer = toRenderBoxModelObject(layer->renderer()->parent())->layer();
+ if (RenderLayerBacking* backing = sourceLayer->backing()) {
+ ASSERT(backing->graphicsLayer()->replicaLayer() == layer->backing()->graphicsLayer());
+ backing->graphicsLayer()->setReplicatedByLayer(0);
+ }
+ }
+
+ layer->clearBacking();
+ layerChanged = true;
+
+ // The layer's cached repaints rects are relative to the repaint container, so change when
+ // compositing changes; we need to update them here.
+ layer->computeRepaintRects();
+
+ // If we need to repaint, do so now that we've removed the backing
+ if (shouldRepaint == CompositingChangeRepaintNow)
+ repaintOnCompositingChange(layer);
+ }
+ }
+
+#if ENABLE(VIDEO)
+ if (layerChanged && layer->renderer()->isVideo()) {
+ // If it's a video, give the media player a chance to hook up to the layer.
+ RenderVideo* video = toRenderVideo(layer->renderer());
+ video->acceleratedRenderingStateChanged();
+ }
+#endif
+
+ if (layerChanged && layer->renderer()->isRenderIFrame()) {
+ RenderLayerCompositor* innerCompositor = iframeContentsCompositor(toRenderIFrame(layer->renderer()));
+ if (innerCompositor && innerCompositor->inCompositingMode())
+ innerCompositor->updateRootLayerAttachment();
+ }
+
+ return layerChanged;
+}
+
+bool RenderLayerCompositor::updateLayerCompositingState(RenderLayer* layer, CompositingChangeRepaint shouldRepaint)
+{
+ bool layerChanged = updateBacking(layer, shouldRepaint);
+
+ // See if we need content or clipping layers. Methods called here should assume
+ // that the compositing state of descendant layers has not been updated yet.
+ if (layer->backing() && layer->backing()->updateGraphicsLayerConfiguration())
+ layerChanged = true;
+
+ return layerChanged;
+}
+
+void RenderLayerCompositor::repaintOnCompositingChange(RenderLayer* layer)
+{
+ // If the renderer is not attached yet, no need to repaint.
+ if (layer->renderer() != m_renderView && !layer->renderer()->parent())
+ return;
+
+ RenderBoxModelObject* repaintContainer = layer->renderer()->containerForRepaint();
+ if (!repaintContainer)
+ repaintContainer = m_renderView;
+
+ layer->repaintIncludingNonCompositingDescendants(repaintContainer);
+ if (repaintContainer == m_renderView) {
+ // The contents of this layer may be moving between the window
+ // and a GraphicsLayer, so we need to make sure the window system
+ // synchronizes those changes on the screen.
+ m_renderView->frameView()->setNeedsOneShotDrawingSynchronization();
+ }
+}
+
+// The bounds of the GraphicsLayer created for a compositing layer is the union of the bounds of all the descendant
+// RenderLayers that are rendered by the composited RenderLayer.
+IntRect RenderLayerCompositor::calculateCompositedBounds(const RenderLayer* layer, const RenderLayer* ancestorLayer)
+{
+ if (!canBeComposited(layer))
+ return IntRect();
+
+ IntRect boundingBoxRect = layer->localBoundingBox();
+ if (layer->renderer()->isRoot()) {
+ // If the root layer becomes composited (e.g. because some descendant with negative z-index is composited),
+ // then it has to be big enough to cover the viewport in order to display the background. This is akin
+ // to the code in RenderBox::paintRootBoxDecorations().
+ if (m_renderView->frameView()) {
+ int rw = m_renderView->frameView()->contentsWidth();
+ int rh = m_renderView->frameView()->contentsHeight();
+
+ boundingBoxRect.setWidth(max(boundingBoxRect.width(), rw - boundingBoxRect.x()));
+ boundingBoxRect.setHeight(max(boundingBoxRect.height(), rh - boundingBoxRect.y()));
+ }
+ }
+
+ IntRect unionBounds = boundingBoxRect;
+
+ if (layer->renderer()->hasOverflowClip() || layer->renderer()->hasMask()) {
+ int ancestorRelX = 0, ancestorRelY = 0;
+ layer->convertToLayerCoords(ancestorLayer, ancestorRelX, ancestorRelY);
+ boundingBoxRect.move(ancestorRelX, ancestorRelY);
+ return boundingBoxRect;
+ }
+
+ if (RenderLayer* reflection = layer->reflectionLayer()) {
+ if (!reflection->isComposited()) {
+ IntRect childUnionBounds = calculateCompositedBounds(reflection, layer);
+ unionBounds.unite(childUnionBounds);
+ }
+ }
+
+ ASSERT(layer->isStackingContext() || (!layer->m_posZOrderList || layer->m_posZOrderList->size() == 0));
+
+ if (Vector<RenderLayer*>* negZOrderList = layer->negZOrderList()) {
+ size_t listSize = negZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = negZOrderList->at(i);
+ if (!curLayer->isComposited()) {
+ IntRect childUnionBounds = calculateCompositedBounds(curLayer, layer);
+ unionBounds.unite(childUnionBounds);
+ }
+ }
+ }
+
+ if (Vector<RenderLayer*>* posZOrderList = layer->posZOrderList()) {
+ size_t listSize = posZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = posZOrderList->at(i);
+ if (!curLayer->isComposited()) {
+ IntRect childUnionBounds = calculateCompositedBounds(curLayer, layer);
+ unionBounds.unite(childUnionBounds);
+ }
+ }
+ }
+
+ if (Vector<RenderLayer*>* normalFlowList = layer->normalFlowList()) {
+ size_t listSize = normalFlowList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = normalFlowList->at(i);
+ if (!curLayer->isComposited()) {
+ IntRect curAbsBounds = calculateCompositedBounds(curLayer, layer);
+ unionBounds.unite(curAbsBounds);
+ }
+ }
+ }
+
+ if (layer->paintsWithTransform(PaintBehaviorNormal)) {
+ TransformationMatrix* affineTrans = layer->transform();
+ boundingBoxRect = affineTrans->mapRect(boundingBoxRect);
+ unionBounds = affineTrans->mapRect(unionBounds);
+ }
+
+ int ancestorRelX = 0, ancestorRelY = 0;
+ layer->convertToLayerCoords(ancestorLayer, ancestorRelX, ancestorRelY);
+ unionBounds.move(ancestorRelX, ancestorRelY);
+
+ return unionBounds;
+}
+
+void RenderLayerCompositor::layerWasAdded(RenderLayer* /*parent*/, RenderLayer* /*child*/)
+{
+ setCompositingLayersNeedRebuild();
+}
+
+void RenderLayerCompositor::layerWillBeRemoved(RenderLayer* parent, RenderLayer* child)
+{
+ if (!child->isComposited() || parent->renderer()->documentBeingDestroyed())
+ return;
+
+ setCompositingParent(child, 0);
+
+ RenderLayer* compLayer = parent->enclosingCompositingLayer();
+ if (compLayer) {
+ ASSERT(compLayer->backing());
+ IntRect compBounds = child->backing()->compositedBounds();
+
+ int offsetX = 0, offsetY = 0;
+ child->convertToLayerCoords(compLayer, offsetX, offsetY);
+ compBounds.move(offsetX, offsetY);
+
+ compLayer->setBackingNeedsRepaintInRect(compBounds);
+
+ // The contents of this layer may be moving from a GraphicsLayer to the window,
+ // so we need to make sure the window system synchronizes those changes on the screen.
+ m_renderView->frameView()->setNeedsOneShotDrawingSynchronization();
+ }
+
+ setCompositingLayersNeedRebuild();
+}
+
+RenderLayer* RenderLayerCompositor::enclosingNonStackingClippingLayer(const RenderLayer* layer) const
+{
+ for (RenderLayer* curr = layer->parent(); curr != 0; curr = curr->parent()) {
+ if (curr->isStackingContext())
+ return 0;
+
+ if (curr->renderer()->hasOverflowClip() || curr->renderer()->hasClip())
+ return curr;
+ }
+ return 0;
+}
+
+void RenderLayerCompositor::addToOverlapMap(OverlapMap& overlapMap, RenderLayer* layer, IntRect& layerBounds, bool& boundsComputed)
+{
+ if (layer->isRootLayer())
+ return;
+
+ if (!boundsComputed) {
+ layerBounds = layer->renderer()->localToAbsoluteQuad(FloatRect(layer->localBoundingBox())).enclosingBoundingBox();
+ // Empty rects never intersect, but we need them to for the purposes of overlap testing.
+ if (layerBounds.isEmpty())
+ layerBounds.setSize(IntSize(1, 1));
+ boundsComputed = true;
+ }
+
+ overlapMap.add(layer, layerBounds);
+}
+
+bool RenderLayerCompositor::overlapsCompositedLayers(OverlapMap& overlapMap, const IntRect& layerBounds)
+{
+ RenderLayerCompositor::OverlapMap::const_iterator end = overlapMap.end();
+ for (RenderLayerCompositor::OverlapMap::const_iterator it = overlapMap.begin(); it != end; ++it) {
+ const IntRect& bounds = it->second;
+ if (layerBounds.intersects(bounds))
+ return true;
+ }
+
+ return false;
+}
+
+// Recurse through the layers in z-index and overflow order (which is equivalent to painting order)
+// For the z-order children of a compositing layer:
+// If a child layers has a compositing layer, then all subsequent layers must
+// be compositing in order to render above that layer.
+//
+// If a child in the negative z-order list is compositing, then the layer itself
+// must be compositing so that its contents render over that child.
+// This implies that its positive z-index children must also be compositing.
+//
+void RenderLayerCompositor::computeCompositingRequirements(RenderLayer* layer, OverlapMap* overlapMap, struct CompositingState& compositingState, bool& layersChanged)
+{
+ layer->updateLayerPosition();
+ layer->updateZOrderLists();
+ layer->updateNormalFlowList();
+
+ // Clear the flag
+ layer->setHasCompositingDescendant(false);
+
+ bool mustOverlapCompositedLayers = compositingState.m_subtreeIsCompositing;
+
+ bool haveComputedBounds = false;
+ IntRect absBounds;
+ if (overlapMap && !overlapMap->isEmpty()) {
+ // If we're testing for overlap, we only need to composite if we overlap something that is already composited.
+ absBounds = layer->renderer()->localToAbsoluteQuad(FloatRect(layer->localBoundingBox())).enclosingBoundingBox();
+ // Empty rects never intersect, but we need them to for the purposes of overlap testing.
+ if (absBounds.isEmpty())
+ absBounds.setSize(IntSize(1, 1));
+ haveComputedBounds = true;
+ mustOverlapCompositedLayers = overlapsCompositedLayers(*overlapMap, absBounds);
+ }
+
+ layer->setMustOverlapCompositedLayers(mustOverlapCompositedLayers);
+
+ // The children of this layer don't need to composite, unless there is
+ // a compositing layer among them, so start by inheriting the compositing
+ // ancestor with m_subtreeIsCompositing set to false.
+ CompositingState childState(compositingState.m_compositingAncestor);
+#ifndef NDEBUG
+ ++childState.m_depth;
+#endif
+
+ bool willBeComposited = needsToBeComposited(layer);
+ if (willBeComposited) {
+ // Tell the parent it has compositing descendants.
+ compositingState.m_subtreeIsCompositing = true;
+ // This layer now acts as the ancestor for kids.
+ childState.m_compositingAncestor = layer;
+ if (overlapMap)
+ addToOverlapMap(*overlapMap, layer, absBounds, haveComputedBounds);
+ }
+
+#if ENABLE(VIDEO)
+ // Video is special. It's a replaced element with a content layer, but has shadow content
+ // for the controller that must render in front. Without this, the controls fail to show
+ // when the video element is a stacking context (e.g. due to opacity or transform).
+ if (willBeComposited && layer->renderer()->isVideo())
+ childState.m_subtreeIsCompositing = true;
+#endif
+
+ if (layer->isStackingContext()) {
+ ASSERT(!layer->m_zOrderListsDirty);
+ if (Vector<RenderLayer*>* negZOrderList = layer->negZOrderList()) {
+ size_t listSize = negZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = negZOrderList->at(i);
+ computeCompositingRequirements(curLayer, overlapMap, childState, layersChanged);
+
+ // If we have to make a layer for this child, make one now so we can have a contents layer
+ // (since we need to ensure that the -ve z-order child renders underneath our contents).
+ if (!willBeComposited && childState.m_subtreeIsCompositing) {
+ // make layer compositing
+ layer->setMustOverlapCompositedLayers(true);
+ childState.m_compositingAncestor = layer;
+ if (overlapMap)
+ addToOverlapMap(*overlapMap, layer, absBounds, haveComputedBounds);
+ willBeComposited = true;
+ }
+ }
+ }
+ }
+
+ ASSERT(!layer->m_normalFlowListDirty);
+ if (Vector<RenderLayer*>* normalFlowList = layer->normalFlowList()) {
+ size_t listSize = normalFlowList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = normalFlowList->at(i);
+ computeCompositingRequirements(curLayer, overlapMap, childState, layersChanged);
+ }
+ }
+
+ if (layer->isStackingContext()) {
+ if (Vector<RenderLayer*>* posZOrderList = layer->posZOrderList()) {
+ size_t listSize = posZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = posZOrderList->at(i);
+ computeCompositingRequirements(curLayer, overlapMap, childState, layersChanged);
+ }
+ }
+ }
+
+ // If we just entered compositing mode, the root will have become composited (as long as accelerated compositing is enabled).
+ if (layer->isRootLayer()) {
+ if (inCompositingMode() && m_hasAcceleratedCompositing)
+ willBeComposited = true;
+ }
+
+ ASSERT(willBeComposited == needsToBeComposited(layer));
+
+ // If we have a software transform, and we have layers under us, we need to also
+ // be composited. Also, if we have opacity < 1, then we need to be a layer so that
+ // the child layers are opaque, then rendered with opacity on this layer.
+ if (!willBeComposited && canBeComposited(layer) && childState.m_subtreeIsCompositing && requiresCompositingWhenDescendantsAreCompositing(layer->renderer())) {
+ layer->setMustOverlapCompositedLayers(true);
+ if (overlapMap)
+ addToOverlapMap(*overlapMap, layer, absBounds, haveComputedBounds);
+ willBeComposited = true;
+ }
+
+ ASSERT(willBeComposited == needsToBeComposited(layer));
+ if (layer->reflectionLayer())
+ layer->reflectionLayer()->setMustOverlapCompositedLayers(willBeComposited);
+
+ // Subsequent layers in the parent stacking context also need to composite.
+ if (childState.m_subtreeIsCompositing)
+ compositingState.m_subtreeIsCompositing = true;
+
+ // Set the flag to say that this SC has compositing children.
+ layer->setHasCompositingDescendant(childState.m_subtreeIsCompositing);
+
+ // setHasCompositingDescendant() may have changed the answer to needsToBeComposited() when clipping,
+ // so test that again.
+ if (!willBeComposited && canBeComposited(layer) && clipsCompositingDescendants(layer)) {
+ if (overlapMap)
+ addToOverlapMap(*overlapMap, layer, absBounds, haveComputedBounds);
+ willBeComposited = true;
+ }
+
+ // If we're back at the root, and no other layers need to be composited, and the root layer itself doesn't need
+ // to be composited, then we can drop out of compositing mode altogether.
+ if (layer->isRootLayer() && !childState.m_subtreeIsCompositing && !requiresCompositingLayer(layer)) {
+ enableCompositingMode(false);
+ willBeComposited = false;
+ }
+
+ // If the layer is going into compositing mode, repaint its old location.
+ ASSERT(willBeComposited == needsToBeComposited(layer));
+ if (!layer->isComposited() && willBeComposited)
+ repaintOnCompositingChange(layer);
+
+ // Update backing now, so that we can use isComposited() reliably during tree traversal in rebuildCompositingLayerTree().
+ if (updateBacking(layer, CompositingChangeRepaintNow))
+ layersChanged = true;
+
+ if (layer->reflectionLayer() && updateLayerCompositingState(layer->reflectionLayer(), CompositingChangeRepaintNow))
+ layersChanged = true;
+}
+
+void RenderLayerCompositor::setCompositingParent(RenderLayer* childLayer, RenderLayer* parentLayer)
+{
+ ASSERT(!parentLayer || childLayer->ancestorCompositingLayer() == parentLayer);
+ ASSERT(childLayer->isComposited());
+
+ // It's possible to be called with a parent that isn't yet composited when we're doing
+ // partial updates as required by painting or hit testing. Just bail in that case;
+ // we'll do a full layer update soon.
+ if (!parentLayer || !parentLayer->isComposited())
+ return;
+
+ if (parentLayer) {
+ GraphicsLayer* hostingLayer = parentLayer->backing()->parentForSublayers();
+ GraphicsLayer* hostedLayer = childLayer->backing()->childForSuperlayers();
+
+ hostingLayer->addChild(hostedLayer);
+ } else
+ childLayer->backing()->childForSuperlayers()->removeFromParent();
+}
+
+void RenderLayerCompositor::removeCompositedChildren(RenderLayer* layer)
+{
+ ASSERT(layer->isComposited());
+
+ GraphicsLayer* hostingLayer = layer->backing()->parentForSublayers();
+ hostingLayer->removeAllChildren();
+}
+
+#if ENABLE(VIDEO)
+bool RenderLayerCompositor::canAccelerateVideoRendering(RenderVideo* o) const
+{
+ if (!m_hasAcceleratedCompositing)
+ return false;
+
+ return o->supportsAcceleratedRendering();
+}
+#endif
+
+void RenderLayerCompositor::rebuildCompositingLayerTree(RenderLayer* layer, const CompositingState& compositingState, Vector<GraphicsLayer*>& childLayersOfEnclosingLayer)
+{
+ // Make the layer compositing if necessary, and set up clipping and content layers.
+ // Note that we can only do work here that is independent of whether the descendant layers
+ // have been processed. computeCompositingRequirements() will already have done the repaint if necessary.
+
+ RenderLayerBacking* layerBacking = layer->backing();
+ if (layerBacking) {
+ // The compositing state of all our children has been updated already, so now
+ // we can compute and cache the composited bounds for this layer.
+ layerBacking->updateCompositedBounds();
+
+ if (RenderLayer* reflection = layer->reflectionLayer()) {
+ if (reflection->backing())
+ reflection->backing()->updateCompositedBounds();
+ }
+
+ layerBacking->updateGraphicsLayerConfiguration();
+ layerBacking->updateGraphicsLayerGeometry();
+
+ if (!layer->parent())
+ updateRootLayerPosition();
+ }
+
+ // If this layer has backing, then we are collecting its children, otherwise appending
+ // to the compositing child list of an enclosing layer.
+ Vector<GraphicsLayer*> layerChildren;
+ Vector<GraphicsLayer*>& childList = layerBacking ? layerChildren : childLayersOfEnclosingLayer;
+
+ CompositingState childState = compositingState;
+ if (layer->isComposited())
+ childState.m_compositingAncestor = layer;
+
+#ifndef NDEBUG
+ ++childState.m_depth;
+#endif
+
+ // The children of this stacking context don't need to composite, unless there is
+ // a compositing layer among them, so start by assuming false.
+ childState.m_subtreeIsCompositing = false;
+
+ if (layer->isStackingContext()) {
+ ASSERT(!layer->m_zOrderListsDirty);
+
+ if (Vector<RenderLayer*>* negZOrderList = layer->negZOrderList()) {
+ size_t listSize = negZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = negZOrderList->at(i);
+ rebuildCompositingLayerTree(curLayer, childState, childList);
+ }
+ }
+
+ // If a negative z-order child is compositing, we get a foreground layer which needs to get parented.
+ if (layerBacking && layerBacking->foregroundLayer())
+ childList.append(layerBacking->foregroundLayer());
+ }
+
+ ASSERT(!layer->m_normalFlowListDirty);
+ if (Vector<RenderLayer*>* normalFlowList = layer->normalFlowList()) {
+ size_t listSize = normalFlowList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = normalFlowList->at(i);
+ rebuildCompositingLayerTree(curLayer, childState, childList);
+ }
+ }
+
+ if (layer->isStackingContext()) {
+ if (Vector<RenderLayer*>* posZOrderList = layer->posZOrderList()) {
+ size_t listSize = posZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = posZOrderList->at(i);
+ rebuildCompositingLayerTree(curLayer, childState, childList);
+ }
+ }
+ }
+
+ if (layerBacking) {
+ bool parented = false;
+ if (layer->renderer()->isRenderIFrame())
+ parented = parentIFrameContentLayers(toRenderIFrame(layer->renderer()));
+
+ if (!parented)
+ layerBacking->parentForSublayers()->setChildren(layerChildren);
+
+ childLayersOfEnclosingLayer.append(layerBacking->childForSuperlayers());
+ }
+}
+
+void RenderLayerCompositor::updateContentLayerOffset(const IntPoint& contentsOffset)
+{
+ if (m_clipLayer) {
+ FrameView* frameView = m_renderView->frameView();
+ m_clipLayer->setPosition(contentsOffset);
+ m_clipLayer->setSize(FloatSize(frameView->layoutWidth(), frameView->layoutHeight()));
+
+ IntPoint scrollPosition = frameView->scrollPosition();
+ m_scrollLayer->setPosition(FloatPoint(-scrollPosition.x(), -scrollPosition.y()));
+ }
+}
+
+void RenderLayerCompositor::updateContentLayerScrollPosition(const IntPoint& scrollPosition)
+{
+ if (m_scrollLayer)
+ m_scrollLayer->setPosition(FloatPoint(-scrollPosition.x(), -scrollPosition.y()));
+}
+
+RenderLayerCompositor* RenderLayerCompositor::iframeContentsCompositor(RenderIFrame* renderer)
+{
+ HTMLIFrameElement* element = static_cast<HTMLIFrameElement*>(renderer->node());
+ if (Document* contentDocument = element->contentDocument()) {
+ if (RenderView* view = contentDocument->renderView())
+ return view->compositor();
+ }
+ return 0;
+}
+
+bool RenderLayerCompositor::parentIFrameContentLayers(RenderIFrame* renderer)
+{
+ RenderLayerCompositor* innerCompositor = iframeContentsCompositor(renderer);
+ if (!innerCompositor || !innerCompositor->inCompositingMode() || innerCompositor->rootLayerAttachment() != RootLayerAttachedViaEnclosingIframe)
+ return false;
+
+ RenderLayer* layer = renderer->layer();
+ if (!layer->isComposited())
+ return false;
+
+ RenderLayerBacking* backing = layer->backing();
+ GraphicsLayer* hostingLayer = backing->parentForSublayers();
+ GraphicsLayer* rootLayer = innerCompositor->rootPlatformLayer();
+ if (hostingLayer->children().size() != 1 || hostingLayer->children()[0] != rootLayer) {
+ hostingLayer->removeAllChildren();
+ hostingLayer->addChild(rootLayer);
+ }
+ return true;
+}
+
+// This just updates layer geometry without changing the hierarchy.
+void RenderLayerCompositor::updateLayerTreeGeometry(RenderLayer* layer)
+{
+ if (RenderLayerBacking* layerBacking = layer->backing()) {
+ // The compositing state of all our children has been updated already, so now
+ // we can compute and cache the composited bounds for this layer.
+ layerBacking->updateCompositedBounds();
+
+ if (RenderLayer* reflection = layer->reflectionLayer()) {
+ if (reflection->backing())
+ reflection->backing()->updateCompositedBounds();
+ }
+
+ layerBacking->updateGraphicsLayerConfiguration();
+ layerBacking->updateGraphicsLayerGeometry();
+
+ if (!layer->parent())
+ updateRootLayerPosition();
+ }
+
+ if (layer->isStackingContext()) {
+ ASSERT(!layer->m_zOrderListsDirty);
+
+ if (Vector<RenderLayer*>* negZOrderList = layer->negZOrderList()) {
+ size_t listSize = negZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i)
+ updateLayerTreeGeometry(negZOrderList->at(i));
+ }
+ }
+
+ ASSERT(!layer->m_normalFlowListDirty);
+ if (Vector<RenderLayer*>* normalFlowList = layer->normalFlowList()) {
+ size_t listSize = normalFlowList->size();
+ for (size_t i = 0; i < listSize; ++i)
+ updateLayerTreeGeometry(normalFlowList->at(i));
+ }
+
+ if (layer->isStackingContext()) {
+ if (Vector<RenderLayer*>* posZOrderList = layer->posZOrderList()) {
+ size_t listSize = posZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i)
+ updateLayerTreeGeometry(posZOrderList->at(i));
+ }
+ }
+}
+
+// Recurs down the RenderLayer tree until its finds the compositing descendants of compositingAncestor and updates their geometry.
+void RenderLayerCompositor::updateCompositingDescendantGeometry(RenderLayer* compositingAncestor, RenderLayer* layer, RenderLayerBacking::UpdateDepth updateDepth)
+{
+ if (layer != compositingAncestor) {
+ if (RenderLayerBacking* layerBacking = layer->backing()) {
+ layerBacking->updateCompositedBounds();
+
+ if (RenderLayer* reflection = layer->reflectionLayer()) {
+ if (reflection->backing())
+ reflection->backing()->updateCompositedBounds();
+ }
+
+ layerBacking->updateGraphicsLayerGeometry();
+ if (updateDepth == RenderLayerBacking::CompositingChildren)
+ return;
+ }
+ }
+
+ if (layer->reflectionLayer())
+ updateCompositingDescendantGeometry(compositingAncestor, layer->reflectionLayer(), updateDepth);
+
+ if (!layer->hasCompositingDescendant())
+ return;
+
+ if (layer->isStackingContext()) {
+ if (Vector<RenderLayer*>* negZOrderList = layer->negZOrderList()) {
+ size_t listSize = negZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i)
+ updateCompositingDescendantGeometry(compositingAncestor, negZOrderList->at(i), updateDepth);
+ }
+ }
+
+ if (Vector<RenderLayer*>* normalFlowList = layer->normalFlowList()) {
+ size_t listSize = normalFlowList->size();
+ for (size_t i = 0; i < listSize; ++i)
+ updateCompositingDescendantGeometry(compositingAncestor, normalFlowList->at(i), updateDepth);
+ }
+
+ if (layer->isStackingContext()) {
+ if (Vector<RenderLayer*>* posZOrderList = layer->posZOrderList()) {
+ size_t listSize = posZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i)
+ updateCompositingDescendantGeometry(compositingAncestor, posZOrderList->at(i), updateDepth);
+ }
+ }
+}
+
+
+void RenderLayerCompositor::repaintCompositedLayersAbsoluteRect(const IntRect& absRect)
+{
+ recursiveRepaintLayerRect(rootRenderLayer(), absRect);
+}
+
+void RenderLayerCompositor::recursiveRepaintLayerRect(RenderLayer* layer, const IntRect& rect)
+{
+ // FIXME: This method does not work correctly with transforms.
+ if (layer->isComposited())
+ layer->setBackingNeedsRepaintInRect(rect);
+
+ if (layer->hasCompositingDescendant()) {
+ if (Vector<RenderLayer*>* negZOrderList = layer->negZOrderList()) {
+ size_t listSize = negZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = negZOrderList->at(i);
+ int x = 0;
+ int y = 0;
+ curLayer->convertToLayerCoords(layer, x, y);
+ IntRect childRect(rect);
+ childRect.move(-x, -y);
+ recursiveRepaintLayerRect(curLayer, childRect);
+ }
+ }
+
+ if (Vector<RenderLayer*>* posZOrderList = layer->posZOrderList()) {
+ size_t listSize = posZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = posZOrderList->at(i);
+ int x = 0;
+ int y = 0;
+ curLayer->convertToLayerCoords(layer, x, y);
+ IntRect childRect(rect);
+ childRect.move(-x, -y);
+ recursiveRepaintLayerRect(curLayer, childRect);
+ }
+ }
+ }
+ if (Vector<RenderLayer*>* normalFlowList = layer->normalFlowList()) {
+ size_t listSize = normalFlowList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = normalFlowList->at(i);
+ int x = 0;
+ int y = 0;
+ curLayer->convertToLayerCoords(layer, x, y);
+ IntRect childRect(rect);
+ childRect.move(-x, -y);
+ recursiveRepaintLayerRect(curLayer, childRect);
+ }
+ }
+}
+
+RenderLayer* RenderLayerCompositor::rootRenderLayer() const
+{
+ return m_renderView->layer();
+}
+
+GraphicsLayer* RenderLayerCompositor::rootPlatformLayer() const
+{
+ return m_clipLayer ? m_clipLayer.get() : m_rootPlatformLayer.get();
+}
+
+void RenderLayerCompositor::didMoveOnscreen()
+{
+ if (!inCompositingMode() || m_rootLayerAttachment != RootLayerUnattached)
+ return;
+
+ RootLayerAttachment attachment = shouldPropagateCompositingToEnclosingIFrame() ? RootLayerAttachedViaEnclosingIframe : RootLayerAttachedViaChromeClient;
+ attachRootPlatformLayer(attachment);
+}
+
+void RenderLayerCompositor::willMoveOffscreen()
+{
+ if (!inCompositingMode() || m_rootLayerAttachment == RootLayerUnattached)
+ return;
+
+ detachRootPlatformLayer();
+}
+
+void RenderLayerCompositor::updateRootLayerPosition()
+{
+ // Eventually we will need to account for scrolling here.
+ // https://bugs.webkit.org/show_bug.cgi?id=38518
+ if (m_rootPlatformLayer)
+ m_rootPlatformLayer->setSize(FloatSize(m_renderView->rightLayoutOverflow(), m_renderView->bottomLayoutOverflow()));
+}
+
+void RenderLayerCompositor::didStartAcceleratedAnimation()
+{
+ // If an accelerated animation or transition runs, we have to turn off overlap checking because
+ // we don't do layout for every frame, but we have to ensure that the layering is
+ // correct between the animating object and other objects on the page.
+ setCompositingConsultsOverlap(false);
+}
+
+bool RenderLayerCompositor::has3DContent() const
+{
+ return layerHas3DContent(rootRenderLayer());
+}
+
+bool RenderLayerCompositor::shouldPropagateCompositingToEnclosingIFrame() const
+{
+ // Parent document content needs to be able to render on top of a composited iframe, so correct behavior
+ // is to have the parent document become composited too. However, this can cause problems on platforms that
+ // use native views for frames (like Mac), so disable that behavior on those platforms for now.
+ HTMLFrameOwnerElement* ownerElement = enclosingIFrameElement();
+ RenderObject* renderer = ownerElement ? ownerElement->renderer() : 0;
+ if (!renderer || !renderer->isRenderIFrame())
+ return false;
+
+#if !PLATFORM(MAC)
+ // On non-Mac platforms, let compositing propagate for all iframes.
+ return true;
+#else
+ // On Mac, only propagate compositing if the iframe is overlapped in the parent
+ // document, or the parent is already compositing.
+ RenderIFrame* iframeRenderer = toRenderIFrame(renderer);
+ if (iframeRenderer->widget()) {
+ ASSERT(iframeRenderer->widget()->isFrameView());
+ FrameView* view = static_cast<FrameView*>(iframeRenderer->widget());
+ if (view->isOverlapped())
+ return true;
+
+ if (RenderView* view = iframeRenderer->view()) {
+ if (view->compositor()->inCompositingMode())
+ return true;
+ }
+ }
+
+ return false;
+#endif
+}
+
+HTMLFrameOwnerElement* RenderLayerCompositor::enclosingIFrameElement() const
+{
+ if (HTMLFrameOwnerElement* ownerElement = m_renderView->document()->ownerElement())
+ return ownerElement->hasTagName(iframeTag) ? ownerElement : 0;
+
+ return 0;
+}
+
+bool RenderLayerCompositor::needsToBeComposited(const RenderLayer* layer) const
+{
+ if (!canBeComposited(layer))
+ return false;
+
+ return requiresCompositingLayer(layer) || layer->mustOverlapCompositedLayers() || (inCompositingMode() && layer->isRootLayer());
+}
+
+// Note: this specifies whether the RL needs a compositing layer for intrinsic reasons.
+// Use needsToBeComposited() to determine if a RL actually needs a compositing layer.
+// static
+bool RenderLayerCompositor::requiresCompositingLayer(const RenderLayer* layer) const
+{
+ RenderObject* renderer = layer->renderer();
+ // The compositing state of a reflection should match that of its reflected layer.
+ if (layer->isReflection()) {
+ renderer = renderer->parent(); // The RenderReplica's parent is the object being reflected.
+ layer = toRenderBoxModelObject(renderer)->layer();
+ }
+ // The root layer always has a compositing layer, but it may not have backing.
+ return requiresCompositingForTransform(renderer)
+ || requiresCompositingForVideo(renderer)
+ || requiresCompositingForCanvas(renderer)
+ || requiresCompositingForPlugin(renderer)
+ || requiresCompositingForIFrame(renderer)
+ || renderer->style()->backfaceVisibility() == BackfaceVisibilityHidden
+ || clipsCompositingDescendants(layer)
+ || requiresCompositingForAnimation(renderer);
+}
+
+bool RenderLayerCompositor::canBeComposited(const RenderLayer* layer) const
+{
+ return m_hasAcceleratedCompositing && layer->isSelfPaintingLayer();
+}
+
+// Return true if the given layer has some ancestor in the RenderLayer hierarchy that clips,
+// up to the enclosing compositing ancestor. This is required because compositing layers are parented
+// according to the z-order hierarchy, yet clipping goes down the renderer hierarchy.
+// Thus, a RenderLayer can be clipped by a RenderLayer that is an ancestor in the renderer hierarchy,
+// but a sibling in the z-order hierarchy.
+bool RenderLayerCompositor::clippedByAncestor(RenderLayer* layer) const
+{
+ if (!layer->isComposited() || !layer->parent())
+ return false;
+
+ RenderLayer* compositingAncestor = layer->ancestorCompositingLayer();
+ if (!compositingAncestor)
+ return false;
+
+ // If the compositingAncestor clips, that will be taken care of by clipsCompositingDescendants(),
+ // so we only care about clipping between its first child that is our ancestor (the computeClipRoot),
+ // and layer.
+ RenderLayer* computeClipRoot = 0;
+ RenderLayer* curr = layer;
+ while (curr) {
+ RenderLayer* next = curr->parent();
+ if (next == compositingAncestor) {
+ computeClipRoot = curr;
+ break;
+ }
+ curr = next;
+ }
+
+ if (!computeClipRoot || computeClipRoot == layer)
+ return false;
+
+ IntRect backgroundRect = layer->backgroundClipRect(computeClipRoot, true);
+ return backgroundRect != ClipRects::infiniteRect();
+}
+
+// Return true if the given layer is a stacking context and has compositing child
+// layers that it needs to clip. In this case we insert a clipping GraphicsLayer
+// into the hierarchy between this layer and its children in the z-order hierarchy.
+bool RenderLayerCompositor::clipsCompositingDescendants(const RenderLayer* layer) const
+{
+ return layer->hasCompositingDescendant() &&
+ (layer->renderer()->hasOverflowClip() || layer->renderer()->hasClip());
+}
+
+bool RenderLayerCompositor::requiresCompositingForTransform(RenderObject* renderer) const
+{
+ RenderStyle* style = renderer->style();
+ // Note that we ask the renderer if it has a transform, because the style may have transforms,
+ // but the renderer may be an inline that doesn't suppport them.
+ return renderer->hasTransform() && (style->transform().has3DOperation() || style->transformStyle3D() == TransformStyle3DPreserve3D || style->hasPerspective());
+}
+
+bool RenderLayerCompositor::requiresCompositingForVideo(RenderObject* renderer) const
+{
+#if ENABLE(VIDEO)
+ if (renderer->isVideo()) {
+ RenderVideo* video = toRenderVideo(renderer);
+ return canAccelerateVideoRendering(video);
+ }
+#if ENABLE(PLUGIN_PROXY_FOR_VIDEO)
+ else if (renderer->isRenderPart()) {
+ if (!m_hasAcceleratedCompositing)
+ return false;
+
+ Node* node = renderer->node();
+ if (!node || (!node->hasTagName(HTMLNames::videoTag) && !node->hasTagName(HTMLNames::audioTag)))
+ return false;
+
+ HTMLMediaElement* mediaElement = static_cast<HTMLMediaElement*>(node);
+ return mediaElement->player() ? mediaElement->player()->supportsAcceleratedRendering() : false;
+ }
+#endif // ENABLE(PLUGIN_PROXY_FOR_VIDEO)
+#else
+ UNUSED_PARAM(renderer);
+#endif
+ return false;
+}
+
+bool RenderLayerCompositor::requiresCompositingForCanvas(RenderObject* renderer) const
+{
+#if ENABLE(3D_CANVAS)
+ if (renderer->isCanvas()) {
+ HTMLCanvasElement* canvas = static_cast<HTMLCanvasElement*>(renderer->node());
+ return canvas->is3D();
+ }
+#else
+ UNUSED_PARAM(renderer);
+#endif
+ return false;
+}
+
+bool RenderLayerCompositor::requiresCompositingForPlugin(RenderObject* renderer) const
+{
+ if (!renderer->isEmbeddedObject())
+ return false;
+
+ RenderEmbeddedObject* embedRenderer = toRenderEmbeddedObject(renderer);
+ if (!embedRenderer->allowsAcceleratedCompositing())
+ return false;
+
+ m_compositingDependsOnGeometry = true;
+
+ // If we can't reliably know the size of the plugin yet, don't change compositing state.
+ if (renderer->needsLayout())
+ return embedRenderer->hasLayer() && embedRenderer->layer()->isComposited();
+
+ // Don't go into compositing mode if height or width are zero, or size is 1x1.
+ IntRect contentBox = embedRenderer->contentBoxRect();
+ return contentBox.height() * contentBox.width() > 1;
+}
+
+bool RenderLayerCompositor::requiresCompositingForIFrame(RenderObject* renderer) const
+{
+ if (!renderer->isRenderIFrame())
+ return false;
+
+ RenderIFrame* iframeRenderer = toRenderIFrame(renderer);
+
+ if (!iframeRenderer->requiresAcceleratedCompositing())
+ return false;
+
+ m_compositingDependsOnGeometry = true;
+
+ RenderLayerCompositor* innerCompositor = iframeContentsCompositor(iframeRenderer);
+ if (!innerCompositor->shouldPropagateCompositingToEnclosingIFrame())
+ return false;
+
+ // If we can't reliably know the size of the iframe yet, don't change compositing state.
+ if (renderer->needsLayout())
+ return iframeRenderer->hasLayer() && iframeRenderer->layer()->isComposited();
+
+ // Don't go into compositing mode if height or width are zero.
+ IntRect contentBox = iframeRenderer->contentBoxRect();
+ return contentBox.height() * contentBox.width() > 0;
+}
+
+bool RenderLayerCompositor::requiresCompositingForAnimation(RenderObject* renderer) const
+{
+ if (AnimationController* animController = renderer->animation()) {
+ return (animController->isRunningAnimationOnRenderer(renderer, CSSPropertyOpacity) && inCompositingMode())
+ || animController->isRunningAnimationOnRenderer(renderer, CSSPropertyWebkitTransform);
+ }
+ return false;
+}
+
+bool RenderLayerCompositor::requiresCompositingWhenDescendantsAreCompositing(RenderObject* renderer) const
+{
+ return renderer->hasTransform() || renderer->isTransparent() || renderer->hasMask() || renderer->hasReflection();
+}
+
+// If an element has negative z-index children, those children render in front of the
+// layer background, so we need an extra 'contents' layer for the foreground of the layer
+// object.
+bool RenderLayerCompositor::needsContentsCompositingLayer(const RenderLayer* layer) const
+{
+ return (layer->m_negZOrderList && layer->m_negZOrderList->size() > 0);
+}
+
+void RenderLayerCompositor::ensureRootPlatformLayer()
+{
+ RootLayerAttachment expectedAttachment = shouldPropagateCompositingToEnclosingIFrame() ? RootLayerAttachedViaEnclosingIframe : RootLayerAttachedViaChromeClient;
+ if (expectedAttachment == m_rootLayerAttachment)
+ return;
+
+ if (!m_rootPlatformLayer) {
+ m_rootPlatformLayer = GraphicsLayer::create(0);
+#ifndef NDEBUG
+ m_rootPlatformLayer->setName("Root platform");
+#endif
+ m_rootPlatformLayer->setSize(FloatSize(m_renderView->rightLayoutOverflow(), m_renderView->bottomLayoutOverflow()));
+ m_rootPlatformLayer->setPosition(FloatPoint());
+
+ // Need to clip to prevent transformed content showing outside this frame
+ m_rootPlatformLayer->setMasksToBounds(true);
+ }
+
+ // The root layer does flipping if we need it on this platform.
+ m_rootPlatformLayer->setGeometryOrientation(expectedAttachment == RootLayerAttachedViaEnclosingIframe ? GraphicsLayer::CompositingCoordinatesTopDown : GraphicsLayer::compositingCoordinatesOrientation());
+
+ if (expectedAttachment == RootLayerAttachedViaEnclosingIframe) {
+ if (!m_clipLayer) {
+ ASSERT(!m_scrollLayer);
+ // Create a clipping layer if this is an iframe
+ m_clipLayer = GraphicsLayer::create(0);
+#ifndef NDEBUG
+ m_clipLayer->setName("iframe Clipping");
+#endif
+ m_clipLayer->setMasksToBounds(true);
+
+ m_scrollLayer = GraphicsLayer::create(0);
+#ifndef NDEBUG
+ m_scrollLayer->setName("iframe scrolling");
+#endif
+ // Hook them up
+ m_clipLayer->addChild(m_scrollLayer.get());
+ m_scrollLayer->addChild(m_rootPlatformLayer.get());
+
+ updateContentLayerScrollPosition(m_renderView->frameView()->scrollPosition());
+ }
+ } else if (m_clipLayer) {
+ m_clipLayer->removeAllChildren();
+ m_clipLayer->removeFromParent();
+ m_clipLayer = 0;
+
+ m_scrollLayer->removeAllChildren();
+ m_scrollLayer = 0;
+ }
+
+ // Check to see if we have to change the attachment
+ if (m_rootLayerAttachment != RootLayerUnattached)
+ detachRootPlatformLayer();
+
+ attachRootPlatformLayer(expectedAttachment);
+}
+
+void RenderLayerCompositor::destroyRootPlatformLayer()
+{
+ if (!m_rootPlatformLayer)
+ return;
+
+ detachRootPlatformLayer();
+ if (m_clipLayer) {
+ m_clipLayer->removeAllChildren();
+ m_clipLayer = 0;
+
+ m_scrollLayer->removeAllChildren();
+ m_scrollLayer = 0;
+ }
+ ASSERT(!m_scrollLayer);
+ m_rootPlatformLayer = 0;
+}
+
+void RenderLayerCompositor::attachRootPlatformLayer(RootLayerAttachment attachment)
+{
+ if (!m_rootPlatformLayer)
+ return;
+
+ switch (attachment) {
+ case RootLayerUnattached:
+ ASSERT_NOT_REACHED();
+ break;
+ case RootLayerAttachedViaChromeClient: {
+ Frame* frame = m_renderView->frameView()->frame();
+ Page* page = frame ? frame->page() : 0;
+ if (!page)
+ return;
+
+ page->chrome()->client()->attachRootGraphicsLayer(frame, m_rootPlatformLayer.get());
+ break;
+ }
+ case RootLayerAttachedViaEnclosingIframe: {
+ // The layer will get hooked up via RenderLayerBacking::updateGraphicsLayerConfiguration()
+ // for the iframe's renderer in the parent document.
+ scheduleNeedsStyleRecalc(m_renderView->document()->ownerElement());
+ break;
+ }
+ }
+
+ m_rootLayerAttachment = attachment;
+ rootLayerAttachmentChanged();
+}
+
+void RenderLayerCompositor::detachRootPlatformLayer()
+{
+ if (!m_rootPlatformLayer || m_rootLayerAttachment == RootLayerUnattached)
+ return;
+
+ switch (m_rootLayerAttachment) {
+ case RootLayerAttachedViaEnclosingIframe: {
+ // The layer will get unhooked up via RenderLayerBacking::updateGraphicsLayerConfiguration()
+ // for the iframe's renderer in the parent document.
+ if (m_clipLayer)
+ m_clipLayer->removeFromParent();
+ else
+ m_rootPlatformLayer->removeFromParent();
+
+ if (Element* ownerElement = m_renderView->document()->ownerElement())
+ scheduleNeedsStyleRecalc(ownerElement);
+ break;
+ }
+ case RootLayerAttachedViaChromeClient: {
+ Frame* frame = m_renderView->frameView()->frame();
+ Page* page = frame ? frame->page() : 0;
+ if (!page)
+ return;
+
+ page->chrome()->client()->attachRootGraphicsLayer(frame, 0);
+ }
+ break;
+ case RootLayerUnattached:
+ break;
+ }
+
+ m_rootLayerAttachment = RootLayerUnattached;
+ rootLayerAttachmentChanged();
+}
+
+void RenderLayerCompositor::updateRootLayerAttachment()
+{
+ ensureRootPlatformLayer();
+}
+
+void RenderLayerCompositor::rootLayerAttachmentChanged()
+{
+ // The attachment can affect whether the RenderView layer's paintingGoesToWindow() behavior,
+ // so call updateGraphicsLayerGeometry() to udpate that.
+ RenderLayer* layer = m_renderView->layer();
+ if (RenderLayerBacking* backing = layer ? layer->backing() : 0)
+ backing->updateDrawsContent();
+}
+
+static void needsStyleRecalcCallback(Node* node)
+{
+ node->setNeedsStyleRecalc(SyntheticStyleChange);
+}
+
+void RenderLayerCompositor::scheduleNeedsStyleRecalc(Element* element)
+{
+ if (ContainerNode::postAttachCallbacksAreSuspended())
+ ContainerNode::queuePostAttachCallback(needsStyleRecalcCallback, element);
+ else
+ element->setNeedsStyleRecalc(SyntheticStyleChange);
+}
+
+// IFrames are special, because we hook compositing layers together across iframe boundaries
+// when both parent and iframe content are composited. So when this frame becomes composited, we have
+// to use a synthetic style change to get the iframes into RenderLayers in order to allow them to composite.
+void RenderLayerCompositor::notifyIFramesOfCompositingChange()
+{
+ Frame* frame = m_renderView->frameView() ? m_renderView->frameView()->frame() : 0;
+ if (!frame)
+ return;
+
+ for (Frame* child = frame->tree()->firstChild(); child; child = child->tree()->nextSibling()) {
+ if (child->document() && child->document()->ownerElement())
+ scheduleNeedsStyleRecalc(child->document()->ownerElement());
+ }
+}
+
+bool RenderLayerCompositor::layerHas3DContent(const RenderLayer* layer) const
+{
+ const RenderStyle* style = layer->renderer()->style();
+
+ if (style &&
+ (style->transformStyle3D() == TransformStyle3DPreserve3D ||
+ style->hasPerspective() ||
+ style->transform().has3DOperation()))
+ return true;
+
+ if (layer->isStackingContext()) {
+ if (Vector<RenderLayer*>* negZOrderList = layer->negZOrderList()) {
+ size_t listSize = negZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = negZOrderList->at(i);
+ if (layerHas3DContent(curLayer))
+ return true;
+ }
+ }
+
+ if (Vector<RenderLayer*>* posZOrderList = layer->posZOrderList()) {
+ size_t listSize = posZOrderList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = posZOrderList->at(i);
+ if (layerHas3DContent(curLayer))
+ return true;
+ }
+ }
+ }
+
+ if (Vector<RenderLayer*>* normalFlowList = layer->normalFlowList()) {
+ size_t listSize = normalFlowList->size();
+ for (size_t i = 0; i < listSize; ++i) {
+ RenderLayer* curLayer = normalFlowList->at(i);
+ if (layerHas3DContent(curLayer))
+ return true;
+ }
+ }
+ return false;
+}
+
+} // namespace WebCore
+
+#endif // USE(ACCELERATED_COMPOSITING)
+