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webkit / WebKit / 629efca1f005d07be1ee16f8122590580914f3b8 / . / Source / WebCore / rendering / RenderLayerCompositor.cpp
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/*
* Copyright (C) 2009-2020 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 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"
#include "RenderLayerCompositor.h"
#include "AsyncScrollingCoordinator.h"
#include "CSSPropertyNames.h"
#include "CanvasRenderingContext.h"
#include "Chrome.h"
#include "ChromeClient.h"
#include "Frame.h"
#include "FrameView.h"
#include "FullscreenManager.h"
#include "GraphicsLayer.h"
#include "HTMLCanvasElement.h"
#include "HTMLIFrameElement.h"
#include "HTMLNames.h"
#include "HitTestResult.h"
#include "InspectorInstrumentation.h"
#include "KeyframeEffectStack.h"
#include "LayerAncestorClippingStack.h"
#include "LayerOverlapMap.h"
#include "Logging.h"
#include "NodeList.h"
#include "Page.h"
#include "PageOverlayController.h"
#include "RenderEmbeddedObject.h"
#include "RenderFragmentedFlow.h"
#include "RenderFullScreen.h"
#include "RenderGeometryMap.h"
#include "RenderIFrame.h"
#include "RenderImage.h"
#include "RenderLayerBacking.h"
#include "RenderLayerScrollableArea.h"
#include "RenderVideo.h"
#include "RenderView.h"
#include "RuntimeEnabledFeatures.h"
#include "ScrollingConstraints.h"
#include "Settings.h"
#include "TiledBacking.h"
#include "TransformState.h"
#include <wtf/HexNumber.h>
#include <wtf/MemoryPressureHandler.h>
#include <wtf/SetForScope.h>
#include <wtf/SystemTracing.h>
#include <wtf/text/CString.h>
#include <wtf/text/StringBuilder.h>
#include <wtf/text/StringConcatenateNumbers.h>
#include <wtf/text/TextStream.h>
#if PLATFORM(IOS_FAMILY)
#include "LegacyTileCache.h"
#include "RenderScrollbar.h"
#endif
#if PLATFORM(MAC)
#include "LocalDefaultSystemAppearance.h"
#endif
#if ENABLE(TREE_DEBUGGING)
#include "RenderTreeAsText.h"
#endif
#if ENABLE(MODEL_ELEMENT)
#include "RenderModel.h"
#endif
#if ENABLE(3D_TRANSFORMS)
// This symbol is used to determine from a script whether 3D rendering is enabled (via 'nm').
WEBCORE_EXPORT bool WebCoreHas3DRendering = true;
#endif
#if !PLATFORM(MAC) && !PLATFORM(IOS_FAMILY)
#define USE_COMPOSITING_FOR_SMALL_CANVASES 1
#endif
namespace WebCore {
#if !USE(COMPOSITING_FOR_SMALL_CANVASES)
static const int canvasAreaThresholdRequiringCompositing = 50 * 100;
#endif
using namespace HTMLNames;
struct ScrollingTreeState {
std::optional<ScrollingNodeID> parentNodeID;
size_t nextChildIndex { 0 };
bool needSynchronousScrollingReasonsUpdate { false };
};
struct RenderLayerCompositor::OverlapExtent {
LayoutRect bounds;
bool extentComputed { false };
bool hasTransformAnimation { false };
bool animationCausesExtentUncertainty { false };
bool knownToBeHaveExtentUncertainty() const { return extentComputed && animationCausesExtentUncertainty; }
};
struct RenderLayerCompositor::CompositingState {
CompositingState(RenderLayer* compAncestor, bool testOverlap = true)
: compositingAncestor(compAncestor)
, testingOverlap(testOverlap)
{
}
CompositingState stateForPaintOrderChildren(RenderLayer& layer) const
{
UNUSED_PARAM(layer);
CompositingState childState(compositingAncestor);
if (layer.isStackingContext())
childState.stackingContextAncestor = &layer;
else
childState.stackingContextAncestor = stackingContextAncestor;
childState.backingSharingAncestor = backingSharingAncestor;
childState.subtreeIsCompositing = false;
childState.testingOverlap = testingOverlap;
childState.fullPaintOrderTraversalRequired = fullPaintOrderTraversalRequired;
childState.descendantsRequireCompositingUpdate = descendantsRequireCompositingUpdate;
childState.ancestorHasTransformAnimation = ancestorHasTransformAnimation;
childState.hasCompositedNonContainedDescendants = false;
#if ENABLE(CSS_COMPOSITING)
childState.hasNotIsolatedCompositedBlendingDescendants = false; // FIXME: should this only be reset for stacking contexts?
#endif
#if !LOG_DISABLED
childState.depth = depth + 1;
#endif
return childState;
}
void updateWithDescendantStateAndLayer(const CompositingState& childState, const RenderLayer& layer, const RenderLayer* ancestorLayer, const OverlapExtent& layerExtent, bool isUnchangedSubtree = false)
{
// Subsequent layers in the parent stacking context also need to composite.
subtreeIsCompositing |= childState.subtreeIsCompositing | layer.isComposited();
if (!isUnchangedSubtree)
fullPaintOrderTraversalRequired |= childState.fullPaintOrderTraversalRequired;
// Turn overlap testing off for later layers if it's already off, or if we have an animating transform.
// Note that if the layer clips its descendants, there's no reason to propagate the child animation to the parent layers. That's because
// we know for sure the animation is contained inside the clipping rectangle, which is already added to the overlap map.
auto canReenableOverlapTesting = [&layer] {
return layer.isComposited() && RenderLayerCompositor::clipsCompositingDescendants(layer);
};
if ((!childState.testingOverlap && !canReenableOverlapTesting()) || layerExtent.knownToBeHaveExtentUncertainty())
testingOverlap = false;
auto computeHasCompositedNonContainedDescendants = [&] {
if (hasCompositedNonContainedDescendants)
return true;
if (!ancestorLayer)
return false;
if (!layer.isComposited())
return false;
if (!layer.renderer().isOutOfFlowPositioned())
return false;
if (layer.ancestorLayerIsInContainingBlockChain(*ancestorLayer))
return false;
return true;
};
hasCompositedNonContainedDescendants = computeHasCompositedNonContainedDescendants();
#if ENABLE(CSS_COMPOSITING)
if ((layer.isComposited() && layer.hasBlendMode()) || (layer.hasNotIsolatedCompositedBlendingDescendants() && !layer.isolatesCompositedBlending()))
hasNotIsolatedCompositedBlendingDescendants = true;
#endif
}
bool hasNonRootCompositedAncestor() const
{
return compositingAncestor && !compositingAncestor->isRenderViewLayer();
}
RenderLayer* compositingAncestor;
RenderLayer* backingSharingAncestor { nullptr };
RenderLayer* stackingContextAncestor { nullptr };
bool subtreeIsCompositing { false };
bool testingOverlap { true };
bool fullPaintOrderTraversalRequired { false };
bool descendantsRequireCompositingUpdate { false };
bool ancestorHasTransformAnimation { false };
bool hasCompositedNonContainedDescendants { false };
#if ENABLE(CSS_COMPOSITING)
bool hasNotIsolatedCompositedBlendingDescendants { false };
#endif
#if !LOG_DISABLED
unsigned depth { 0 };
#endif
};
struct RenderLayerCompositor::UpdateBackingTraversalState {
UpdateBackingTraversalState(RenderLayer* compAncestor = nullptr, Vector<RenderLayer*>* clippedLayers = nullptr, Vector<RenderLayer*>* overflowScrollers = nullptr)
: compositingAncestor(compAncestor)
, layersClippedByScrollers(clippedLayers)
, overflowScrollLayers(overflowScrollers)
{
}
UpdateBackingTraversalState stateForDescendants() const
{
UpdateBackingTraversalState state(compositingAncestor, layersClippedByScrollers, overflowScrollLayers);
#if !LOG_DISABLED
state.depth = depth + 1;
#endif
return state;
}
RenderLayer* compositingAncestor;
// List of layers in the current stacking context that are clipped by ancestor scrollers.
Vector<RenderLayer*>* layersClippedByScrollers;
// List of layers with composited overflow:scroll.
Vector<RenderLayer*>* overflowScrollLayers;
#if !LOG_DISABLED
unsigned depth { 0 };
#endif
};
class RenderLayerCompositor::BackingSharingState {
WTF_MAKE_NONCOPYABLE(BackingSharingState);
public:
BackingSharingState() = default;
RenderLayer* backingProviderCandidate() const { return m_backingProviderCandidate; };
void appendSharingLayer(RenderLayer& layer)
{
ASSERT(m_backingProviderCandidate);
m_backingSharingLayers.append(layer);
}
RenderLayer* updateBeforeDescendantTraversal(RenderLayer&, bool willBeComposited);
void updateAfterDescendantTraversal(RenderLayer&, RenderLayer* preDescendantProviderCandidate, RenderLayer* stackingContextAncestor);
bool isPotentialBackingSharingLayer(const RenderLayer& layer) const
{
return m_backingSharingLayers.contains(&layer);
}
bool canIncludeLayer(const RenderLayer&) const;
// Add a layer that would repaint into a layer in m_backingSharingLayers.
// That repaint has to wait until we've set the provider's backing-sharing layers.
void addLayerNeedingRepaint(RenderLayer& layer)
{
m_layersPendingRepaint.add(layer);
}
private:
void layerWillBeComposited(RenderLayer&);
void startBackingSharingSequence(RenderLayer& candidateLayer, RenderLayer* candidateStackingContext);
void endBackingSharingSequence();
void issuePendingRepaints();
RenderLayer* m_backingProviderCandidate { nullptr };
RenderLayer* m_backingProviderStackingContext { nullptr };
Vector<WeakPtr<RenderLayer>> m_backingSharingLayers;
WeakHashSet<RenderLayer> m_layersPendingRepaint;
};
void RenderLayerCompositor::BackingSharingState::startBackingSharingSequence(RenderLayer& candidateLayer, RenderLayer* candidateStackingContext)
{
ASSERT(!m_backingProviderCandidate);
ASSERT(m_backingSharingLayers.isEmpty());
m_backingProviderCandidate = &candidateLayer;
m_backingProviderStackingContext = candidateStackingContext;
}
void RenderLayerCompositor::BackingSharingState::endBackingSharingSequence()
{
if (!m_backingProviderCandidate)
return;
m_backingProviderCandidate->backing()->setBackingSharingLayers(WTFMove(m_backingSharingLayers));
m_backingSharingLayers.clear();
issuePendingRepaints();
m_backingProviderCandidate = nullptr;
}
bool RenderLayerCompositor::BackingSharingState::canIncludeLayer(const RenderLayer& layer) const
{
// Disable sharing when painting shared layers doesn't work correctly.
if (layer.hasReflection())
return false;
return m_backingProviderCandidate && layer.ancestorLayerIsInContainingBlockChain(*m_backingProviderCandidate);
}
RenderLayer* RenderLayerCompositor::BackingSharingState::updateBeforeDescendantTraversal(RenderLayer& layer, bool willBeComposited)
{
layer.setBackingProviderLayer(nullptr);
LOG_WITH_STREAM(Compositing, stream << "BackingSharingState::updateBeforeDescendantTraversal: layer " << &layer << " will be composited " << willBeComposited);
// A layer that composites resets backing-sharing, since subsequent layers need to composite to overlap it.
if (willBeComposited) {
LOG_WITH_STREAM(Compositing, stream << " ending sharing sequence on " << m_backingProviderCandidate);
m_backingSharingLayers.removeAll(&layer);
endBackingSharingSequence();
}
return m_backingProviderCandidate;
}
void RenderLayerCompositor::BackingSharingState::updateAfterDescendantTraversal(RenderLayer& layer, RenderLayer* preDescendantProviderCandidate, RenderLayer* stackingContextAncestor)
{
LOG_WITH_STREAM(Compositing, stream << "BackingSharingState::updateAfterDescendantTraversal for layer " << &layer << " is composited " << layer.isComposited());
if (layer.isComposited()) {
// If this layer is being composited, clean up sharing-related state.
layer.disconnectFromBackingProviderLayer();
m_backingSharingLayers.removeAll(&layer);
}
// Backing sharing is constrained to layers in the same stacking context.
if (&layer == m_backingProviderStackingContext) {
ASSERT(&layer != m_backingProviderCandidate);
LOG_WITH_STREAM(Compositing, stream << "BackingSharingState::updateAfterDescendantTraversal: End of stacking context for backing provider " << m_backingProviderCandidate << ", ending sharing sequence with " << m_backingSharingLayers.size() << " sharing layers");
endBackingSharingSequence();
if (layer.isComposited())
layer.backing()->clearBackingSharingLayers();
return;
}
if (!layer.isComposited())
return;
if (!m_backingProviderCandidate) {
LOG_WITH_STREAM(Compositing, stream << "BackingSharingState::updateAfterDescendantTraversal: starting potential sharing sequence for " << &layer);
startBackingSharingSequence(layer, stackingContextAncestor);
} else {
ASSERT(&layer != m_backingProviderCandidate);
layer.backing()->clearBackingSharingLayers();
LOG_WITH_STREAM(Compositing, stream << "BackingSharingState::updateAfterDescendantTraversal: " << &layer << " is composited; maybe ending existing backing sequence with candidate " << m_backingProviderCandidate << " context " << m_backingProviderStackingContext << " with " << m_backingSharingLayers.size() << " sharing layers");
if (m_backingProviderCandidate && preDescendantProviderCandidate == m_backingProviderCandidate) {
m_backingSharingLayers.removeAll(&layer);
endBackingSharingSequence();
}
}
}
void RenderLayerCompositor::BackingSharingState::issuePendingRepaints()
{
for (auto& layer : m_layersPendingRepaint) {
LOG_WITH_STREAM(Compositing, stream << "Issuing postponed repaint of layer " << &layer);
layer.computeRepaintRectsIncludingDescendants();
layer.compositor().repaintOnCompositingChange(layer);
}
m_layersPendingRepaint.clear();
}
#if !LOG_DISABLED || ENABLE(TREE_DEBUGGING)
static inline bool compositingLogEnabled()
{
return LogCompositing.state == WTFLogChannelState::On;
}
static inline bool layersLogEnabled()
{
return LogLayers.state == WTFLogChannelState::On;
}
#endif
RenderLayerCompositor::RenderLayerCompositor(RenderView& renderView)
: m_renderView(renderView)
, m_updateCompositingLayersTimer(*this, &RenderLayerCompositor::updateCompositingLayersTimerFired)
{
#if PLATFORM(IOS_FAMILY)
if (m_renderView.frameView().platformWidget())
m_legacyScrollingLayerCoordinator = makeUnique<LegacyWebKitScrollingLayerCoordinator>(page().chrome().client(), isMainFrameCompositor());
#endif
}
RenderLayerCompositor::~RenderLayerCompositor()
{
// Take care that the owned GraphicsLayers are deleted first as their destructors may call back here.
GraphicsLayer::unparentAndClear(m_rootContentsLayer);
GraphicsLayer::unparentAndClear(m_clipLayer);
GraphicsLayer::unparentAndClear(m_scrollContainerLayer);
GraphicsLayer::unparentAndClear(m_scrolledContentsLayer);
GraphicsLayer::unparentAndClear(m_overflowControlsHostLayer);
GraphicsLayer::unparentAndClear(m_layerForHorizontalScrollbar);
GraphicsLayer::unparentAndClear(m_layerForVerticalScrollbar);
GraphicsLayer::unparentAndClear(m_layerForScrollCorner);
#if HAVE(RUBBER_BANDING)
GraphicsLayer::unparentAndClear(m_layerForOverhangAreas);
GraphicsLayer::unparentAndClear(m_contentShadowLayer);
GraphicsLayer::unparentAndClear(m_layerForTopOverhangArea);
GraphicsLayer::unparentAndClear(m_layerForBottomOverhangArea);
GraphicsLayer::unparentAndClear(m_layerForHeader);
GraphicsLayer::unparentAndClear(m_layerForFooter);
#endif
ASSERT(m_rootLayerAttachment == RootLayerUnattached);
}
void RenderLayerCompositor::enableCompositingMode(bool enable /* = true */)
{
if (enable != m_compositing) {
m_compositing = enable;
if (m_compositing) {
ensureRootLayer();
notifyIFramesOfCompositingChange();
} else
destroyRootLayer();
m_renderView.layer()->setNeedsPostLayoutCompositingUpdate();
}
}
void RenderLayerCompositor::cacheAcceleratedCompositingFlags()
{
auto& settings = m_renderView.settings();
bool hasAcceleratedCompositing = settings.acceleratedCompositingEnabled();
// 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) {
m_compositingTriggers = page().chrome().client().allowedCompositingTriggers();
hasAcceleratedCompositing = m_compositingTriggers;
}
bool showDebugBorders = settings.showDebugBorders();
bool showRepaintCounter = settings.showRepaintCounter();
bool acceleratedDrawingEnabled = settings.acceleratedDrawingEnabled();
bool displayListDrawingEnabled = settings.displayListDrawingEnabled();
// forceCompositingMode for subframes can only be computed after layout.
bool forceCompositingMode = m_forceCompositingMode;
if (isMainFrameCompositor())
forceCompositingMode = m_renderView.settings().forceCompositingMode() && hasAcceleratedCompositing;
if (hasAcceleratedCompositing != m_hasAcceleratedCompositing || showDebugBorders != m_showDebugBorders || showRepaintCounter != m_showRepaintCounter || forceCompositingMode != m_forceCompositingMode) {
if (auto* rootLayer = m_renderView.layer()) {
rootLayer->setNeedsCompositingConfigurationUpdate();
rootLayer->setDescendantsNeedUpdateBackingAndHierarchyTraversal();
}
}
bool debugBordersChanged = m_showDebugBorders != showDebugBorders;
m_hasAcceleratedCompositing = hasAcceleratedCompositing;
m_forceCompositingMode = forceCompositingMode;
m_showDebugBorders = showDebugBorders;
m_showRepaintCounter = showRepaintCounter;
m_acceleratedDrawingEnabled = acceleratedDrawingEnabled;
m_displayListDrawingEnabled = displayListDrawingEnabled;
if (debugBordersChanged) {
if (m_layerForHorizontalScrollbar)
m_layerForHorizontalScrollbar->setShowDebugBorder(m_showDebugBorders);
if (m_layerForVerticalScrollbar)
m_layerForVerticalScrollbar->setShowDebugBorder(m_showDebugBorders);
if (m_layerForScrollCorner)
m_layerForScrollCorner->setShowDebugBorder(m_showDebugBorders);
}
if (updateCompositingPolicy())
rootRenderLayer().setDescendantsNeedCompositingRequirementsTraversal();
}
void RenderLayerCompositor::cacheAcceleratedCompositingFlagsAfterLayout()
{
cacheAcceleratedCompositingFlags();
if (isMainFrameCompositor())
return;
RequiresCompositingData queryData;
bool forceCompositingMode = m_hasAcceleratedCompositing && m_renderView.settings().forceCompositingMode() && requiresCompositingForScrollableFrame(queryData);
if (forceCompositingMode != m_forceCompositingMode) {
m_forceCompositingMode = forceCompositingMode;
rootRenderLayer().setDescendantsNeedCompositingRequirementsTraversal();
}
}
bool RenderLayerCompositor::updateCompositingPolicy()
{
if (!usesCompositing())
return false;
auto currentPolicy = m_compositingPolicy;
if (page().compositingPolicyOverride()) {
m_compositingPolicy = page().compositingPolicyOverride().value();
return m_compositingPolicy != currentPolicy;
}
static auto cachedMemoryPolicy = WTF::MemoryUsagePolicy::Unrestricted;
static MonotonicTime cachedMemoryPolicyTime;
static constexpr auto memoryPolicyCachingDuration = 2_s;
auto now = MonotonicTime::now();
if (now - cachedMemoryPolicyTime > memoryPolicyCachingDuration) {
cachedMemoryPolicy = MemoryPressureHandler::singleton().currentMemoryUsagePolicy();
cachedMemoryPolicyTime = now;
}
m_compositingPolicy = cachedMemoryPolicy == WTF::MemoryUsagePolicy::Unrestricted ? CompositingPolicy::Normal : CompositingPolicy::Conservative;
return m_compositingPolicy != currentPolicy;
}
bool RenderLayerCompositor::canRender3DTransforms() const
{
return hasAcceleratedCompositing() && (m_compositingTriggers & ChromeClient::ThreeDTransformTrigger);
}
void RenderLayerCompositor::willRecalcStyle()
{
cacheAcceleratedCompositingFlags();
}
bool RenderLayerCompositor::didRecalcStyleWithNoPendingLayout()
{
return updateCompositingLayers(CompositingUpdateType::AfterStyleChange);
}
void RenderLayerCompositor::customPositionForVisibleRectComputation(const GraphicsLayer* graphicsLayer, FloatPoint& position) const
{
if (graphicsLayer != m_scrolledContentsLayer.get())
return;
FloatPoint scrollPosition = -position;
if (m_renderView.frameView().scrollBehaviorForFixedElements() == StickToDocumentBounds)
scrollPosition = m_renderView.frameView().constrainScrollPositionForOverhang(roundedIntPoint(scrollPosition));
position = -scrollPosition;
}
void RenderLayerCompositor::notifyFlushRequired(const GraphicsLayer*)
{
scheduleRenderingUpdate();
}
void RenderLayerCompositor::scheduleRenderingUpdate()
{
ASSERT(!m_flushingLayers);
page().scheduleRenderingUpdate(RenderingUpdateStep::LayerFlush);
}
FloatRect RenderLayerCompositor::visibleRectForLayerFlushing() const
{
const FrameView& frameView = m_renderView.frameView();
#if PLATFORM(IOS_FAMILY)
return frameView.exposedContentRect();
#else
// Having a m_scrolledContentsLayer indicates that we're doing scrolling via GraphicsLayers.
FloatRect visibleRect = m_scrolledContentsLayer ? FloatRect({ }, frameView.sizeForVisibleContent()) : frameView.visibleContentRect();
if (auto exposedRect = frameView.viewExposedRect())
visibleRect.intersect(*exposedRect);
return visibleRect;
#endif
}
void RenderLayerCompositor::flushPendingLayerChanges(bool isFlushRoot)
{
// FrameView::flushCompositingStateIncludingSubframes() flushes each subframe,
// but GraphicsLayer::flushCompositingState() will cross frame boundaries
// if the GraphicsLayers are connected (the RootLayerAttachedViaEnclosingFrame case).
// As long as we're not the root of the flush, we can bail.
if (!isFlushRoot && rootLayerAttachment() == RootLayerAttachedViaEnclosingFrame)
return;
if (rootLayerAttachment() == RootLayerUnattached) {
m_shouldFlushOnReattach = true;
return;
}
ASSERT(!m_flushingLayers);
{
SetForScope flushingLayersScope(m_flushingLayers, true);
if (auto* rootLayer = rootGraphicsLayer()) {
#if ENABLE(ASYNC_SCROLLING) && ENABLE(SCROLLING_THREAD)
LayerTreeHitTestLocker layerLocker(scrollingCoordinator());
#endif
FloatRect visibleRect = visibleRectForLayerFlushing();
LOG_WITH_STREAM(Compositing, stream << "\nRenderLayerCompositor " << this << " flushPendingLayerChanges (is root " << isFlushRoot << ") visible rect " << visibleRect);
rootLayer->flushCompositingState(visibleRect);
}
ASSERT(m_flushingLayers);
#if ENABLE(TREE_DEBUGGING)
if (layersLogEnabled()) {
LOG(Layers, "RenderLayerCompositor::flushPendingLayerChanges");
showGraphicsLayerTree(rootGraphicsLayer());
}
#endif
}
#if PLATFORM(IOS_FAMILY)
updateScrollCoordinatedLayersAfterFlushIncludingSubframes();
if (isFlushRoot)
page().chrome().client().didFlushCompositingLayers();
#endif
++m_layerFlushCount;
}
#if PLATFORM(IOS_FAMILY)
void RenderLayerCompositor::updateScrollCoordinatedLayersAfterFlushIncludingSubframes()
{
updateScrollCoordinatedLayersAfterFlush();
auto& frame = m_renderView.frameView().frame();
for (Frame* subframe = frame.tree().firstChild(); subframe; subframe = subframe->tree().traverseNext(&frame)) {
auto* view = subframe->contentRenderer();
if (!view)
continue;
view->compositor().updateScrollCoordinatedLayersAfterFlush();
}
}
void RenderLayerCompositor::updateScrollCoordinatedLayersAfterFlush()
{
if (m_legacyScrollingLayerCoordinator) {
m_legacyScrollingLayerCoordinator->registerAllViewportConstrainedLayers(*this);
m_legacyScrollingLayerCoordinator->registerAllScrollingLayers();
}
}
#endif
void RenderLayerCompositor::didChangePlatformLayerForLayer(RenderLayer& layer, const GraphicsLayer*)
{
auto* scrollingCoordinator = this->scrollingCoordinator();
if (!scrollingCoordinator)
return;
auto* backing = layer.backing();
if (auto nodeID = backing->scrollingNodeIDForRole(ScrollCoordinationRole::Scrolling))
updateScrollingNodeLayers(nodeID, layer, *scrollingCoordinator);
if (auto* clippingStack = layer.backing()->ancestorClippingStack())
clippingStack->updateScrollingNodeLayers(*scrollingCoordinator);
if (auto nodeID = backing->scrollingNodeIDForRole(ScrollCoordinationRole::ViewportConstrained))
scrollingCoordinator->setNodeLayers(nodeID, { backing->graphicsLayer() });
if (auto nodeID = backing->scrollingNodeIDForRole(ScrollCoordinationRole::FrameHosting))
scrollingCoordinator->setNodeLayers(nodeID, { backing->graphicsLayer() });
if (auto nodeID = backing->scrollingNodeIDForRole(ScrollCoordinationRole::Positioning))
scrollingCoordinator->setNodeLayers(nodeID, { backing->graphicsLayer() });
}
void RenderLayerCompositor::didPaintBacking(RenderLayerBacking*)
{
auto& frameView = m_renderView.frameView();
frameView.setLastPaintTime(MonotonicTime::now());
if (frameView.milestonesPendingPaint())
frameView.firePaintRelatedMilestonesIfNeeded();
}
void RenderLayerCompositor::didChangeVisibleRect()
{
auto* rootLayer = rootGraphicsLayer();
if (!rootLayer)
return;
FloatRect visibleRect = visibleRectForLayerFlushing();
bool requiresFlush = rootLayer->visibleRectChangeRequiresFlush(visibleRect);
LOG_WITH_STREAM(Compositing, stream << "RenderLayerCompositor::didChangeVisibleRect " << visibleRect << " requiresFlush " << requiresFlush);
if (requiresFlush)
scheduleRenderingUpdate();
}
void RenderLayerCompositor::notifyFlushBeforeDisplayRefresh(const GraphicsLayer*)
{
if (!m_layerUpdater) {
PlatformDisplayID displayID = page().chrome().displayID();
m_layerUpdater = makeUnique<GraphicsLayerUpdater>(*this, displayID);
}
m_layerUpdater->scheduleUpdate();
}
void RenderLayerCompositor::flushLayersSoon(GraphicsLayerUpdater&)
{
scheduleRenderingUpdate();
}
DisplayRefreshMonitorFactory* RenderLayerCompositor::displayRefreshMonitorFactory()
{
return page().chrome().client().displayRefreshMonitorFactory();
}
void RenderLayerCompositor::layerTiledBackingUsageChanged(const GraphicsLayer* graphicsLayer, bool usingTiledBacking)
{
if (usingTiledBacking) {
++m_layersWithTiledBackingCount;
graphicsLayer->tiledBacking()->setIsInWindow(page().isInWindow());
} else {
ASSERT(m_layersWithTiledBackingCount > 0);
--m_layersWithTiledBackingCount;
}
}
void RenderLayerCompositor::scheduleCompositingLayerUpdate()
{
if (!m_updateCompositingLayersTimer.isActive())
m_updateCompositingLayersTimer.startOneShot(0_s);
}
void RenderLayerCompositor::updateCompositingLayersTimerFired()
{
updateCompositingLayers(CompositingUpdateType::AfterLayout);
}
void RenderLayerCompositor::cancelCompositingLayerUpdate()
{
m_updateCompositingLayersTimer.stop();
}
template<typename ApplyFunctionType>
void RenderLayerCompositor::applyToCompositedLayerIncludingDescendants(RenderLayer& layer, const ApplyFunctionType& function)
{
if (layer.isComposited())
function(layer);
for (auto* childLayer = layer.firstChild(); childLayer; childLayer = childLayer->nextSibling())
applyToCompositedLayerIncludingDescendants(*childLayer, function);
}
void RenderLayerCompositor::updateEventRegions()
{
#if ENABLE(ASYNC_SCROLLING)
applyToCompositedLayerIncludingDescendants(*m_renderView.layer(), [](auto& layer) {
layer.backing()->updateEventRegion();
});
#endif
}
static std::optional<ScrollingNodeID> frameHostingNodeForFrame(Frame& frame)
{
if (!frame.document() || !frame.view())
return { };
// Find the frame's enclosing layer in our render tree.
auto* ownerElement = frame.document()->ownerElement();
if (!ownerElement)
return { };
auto* frameRenderer = ownerElement->renderer();
if (!frameRenderer || !is<RenderWidget>(frameRenderer))
return { };
auto& widgetRenderer = downcast<RenderWidget>(*frameRenderer);
if (!widgetRenderer.hasLayer() || !widgetRenderer.layer()->isComposited()) {
LOG(Scrolling, "frameHostingNodeForFrame: frame renderer has no layer or is not composited.");
return { };
}
if (auto frameHostingNodeID = widgetRenderer.layer()->backing()->scrollingNodeIDForRole(ScrollCoordinationRole::FrameHosting))
return frameHostingNodeID;
return { };
}
// Returns true on a successful update.
bool RenderLayerCompositor::updateCompositingLayers(CompositingUpdateType updateType, RenderLayer* updateRoot)
{
LOG_WITH_STREAM(Compositing, stream << "RenderLayerCompositor " << this << " [" << m_renderView.frameView() << "] updateCompositingLayers " << updateType << " contentLayersCount " << m_contentLayersCount);
TraceScope tracingScope(CompositingUpdateStart, CompositingUpdateEnd);
#if ENABLE(TREE_DEBUGGING)
if (compositingLogEnabled())
showPaintOrderTree(m_renderView.layer());
#endif
if (updateType == CompositingUpdateType::AfterStyleChange || updateType == CompositingUpdateType::AfterLayout)
cacheAcceleratedCompositingFlagsAfterLayout(); // Some flags (e.g. forceCompositingMode) depend on layout.
m_updateCompositingLayersTimer.stop();
ASSERT(m_renderView.document().backForwardCacheState() == Document::NotInBackForwardCache
|| m_renderView.document().backForwardCacheState() == Document::AboutToEnterBackForwardCache);
// Compositing layers will be updated in Document::setVisualUpdatesAllowed(bool) if suppressed here.
if (!m_renderView.document().visualUpdatesAllowed())
return false;
// Avoid updating the layers with old values. Compositing layers will be updated after the layout is finished.
// This happens when m_updateCompositingLayersTimer fires before layout is updated.
if (m_renderView.needsLayout()) {
LOG_WITH_STREAM(Compositing, stream << "RenderLayerCompositor " << this << " updateCompositingLayers " << updateType << " - m_renderView.needsLayout, bailing ");
return false;
}
if (!m_compositing && (m_forceCompositingMode || (isMainFrameCompositor() && page().pageOverlayController().overlayCount())))
enableCompositingMode(true);
bool isPageScroll = !updateRoot || updateRoot == &rootRenderLayer();
updateRoot = &rootRenderLayer();
if (updateType == CompositingUpdateType::OnScroll || updateType == CompositingUpdateType::OnCompositedScroll) {
// We only get here if we didn't scroll on the scrolling thread, so this update needs to re-position viewport-constrained layers.
if (m_renderView.settings().acceleratedCompositingForFixedPositionEnabled() && isPageScroll) {
if (auto* viewportConstrainedObjects = m_renderView.frameView().viewportConstrainedObjects()) {
for (auto& renderer : *viewportConstrainedObjects) {
if (auto* layer = renderer.layer())
layer->setNeedsCompositingGeometryUpdate();
}
}
}
// Scrolling can affect overlap. FIXME: avoid for page scrolling.
updateRoot->setDescendantsNeedCompositingRequirementsTraversal();
}
if (updateType == CompositingUpdateType::AfterLayout) {
// Ensure that post-layout updates push new scroll position and viewport rects onto the root node.
rootRenderLayer().setNeedsScrollingTreeUpdate();
}
if (!updateRoot->hasDescendantNeedingCompositingRequirementsTraversal() && !m_compositing) {
LOG_WITH_STREAM(Compositing, stream << " no compositing work to do");
return true;
}
if (!updateRoot->needsAnyCompositingTraversal()) {
LOG_WITH_STREAM(Compositing, stream << " updateRoot has no dirty child and doesn't need update");
return true;
}
++m_compositingUpdateCount;
#if !LOG_DISABLED
MonotonicTime startTime;
if (compositingLogEnabled()) {
++m_rootLayerUpdateCount;
startTime = MonotonicTime::now();
}
if (compositingLogEnabled()) {
m_obligateCompositedLayerCount = 0;
m_secondaryCompositedLayerCount = 0;
m_obligatoryBackingStoreBytes = 0;
m_secondaryBackingStoreBytes = 0;
auto& frame = m_renderView.frameView().frame();
bool isMainFrame = isMainFrameCompositor();
LOG_WITH_STREAM(Compositing, stream << "\nUpdate " << m_rootLayerUpdateCount << " of " << (isMainFrame ? "main frame" : frame.tree().uniqueName().string().utf8().data()) << " - compositing policy is " << m_compositingPolicy);
}
#endif
// FIXME: optimize root-only update.
if (updateRoot->hasDescendantNeedingCompositingRequirementsTraversal() || updateRoot->needsCompositingRequirementsTraversal()) {
auto& rootLayer = rootRenderLayer();
CompositingState compositingState(updateRoot);
BackingSharingState backingSharingState;
LayerOverlapMap overlapMap(rootLayer);
bool descendantHas3DTransform = false;
computeCompositingRequirements(nullptr, rootLayer, overlapMap, compositingState, backingSharingState, descendantHas3DTransform);
}
LOG(Compositing, "\nRenderLayerCompositor::updateCompositingLayers - mid");
#if ENABLE(TREE_DEBUGGING)
if (compositingLogEnabled())
showPaintOrderTree(m_renderView.layer());
#endif
if (updateRoot->hasDescendantNeedingUpdateBackingOrHierarchyTraversal() || updateRoot->needsUpdateBackingOrHierarchyTraversal()) {
ScrollingTreeState scrollingTreeState = { 0, 0 };
if (!m_renderView.frame().isMainFrame())
scrollingTreeState.parentNodeID = frameHostingNodeForFrame(m_renderView.frame());
auto* scrollingCoordinator = this->scrollingCoordinator();
bool hadSubscrollers = scrollingCoordinator ? scrollingCoordinator->hasSubscrollers() : false;
UpdateBackingTraversalState traversalState;
Vector<Ref<GraphicsLayer>> childList;
updateBackingAndHierarchy(*updateRoot, childList, traversalState, scrollingTreeState);
if (scrollingTreeState.needSynchronousScrollingReasonsUpdate)
updateSynchronousScrollingNodes();
// Host the document layer in the RenderView's root layer.
appendDocumentOverlayLayers(childList);
// Even when childList is empty, don't drop out of compositing mode if there are
// composited layers that we didn't hit in our traversal (e.g. because of visibility:hidden).
if (childList.isEmpty() && !needsCompositingForContentOrOverlays())
destroyRootLayer();
else if (m_rootContentsLayer)
m_rootContentsLayer->setChildren(WTFMove(childList));
if (scrollingCoordinator && scrollingCoordinator->hasSubscrollers() != hadSubscrollers)
invalidateEventRegionForAllFrames();
}
#if !LOG_DISABLED
if (compositingLogEnabled()) {
MonotonicTime endTime = MonotonicTime::now();
LOG(Compositing, "Total layers primary secondary obligatory backing (KB) secondary backing(KB) total backing (KB) update time (ms)\n");
LOG(Compositing, "%8d %11d %9d %20.2f %22.2f %22.2f %18.2f\n",
m_obligateCompositedLayerCount + m_secondaryCompositedLayerCount, m_obligateCompositedLayerCount,
m_secondaryCompositedLayerCount, m_obligatoryBackingStoreBytes / 1024, m_secondaryBackingStoreBytes / 1024, (m_obligatoryBackingStoreBytes + m_secondaryBackingStoreBytes) / 1024, (endTime - startTime).milliseconds());
}
#endif
// FIXME: Only do if dirty.
updateRootLayerPosition();
#if ENABLE(TREE_DEBUGGING)
if (compositingLogEnabled()) {
LOG(Compositing, "RenderLayerCompositor::updateCompositingLayers - post");
showPaintOrderTree(m_renderView.layer());
}
#endif
InspectorInstrumentation::layerTreeDidChange(&page());
if (m_renderView.needsRepaintHackAfterCompositingLayerUpdateForDebugOverlaysOnly()) {
m_renderView.repaintRootContents();
m_renderView.setNeedsRepaintHackAfterCompositingLayerUpdateForDebugOverlaysOnly(false);
}
return true;
}
void RenderLayerCompositor::computeCompositingRequirements(RenderLayer* ancestorLayer, RenderLayer& layer, LayerOverlapMap& overlapMap, CompositingState& compositingState, BackingSharingState& backingSharingState, bool& descendantHas3DTransform)
{
layer.updateDescendantDependentFlags();
layer.updateLayerListsIfNeeded();
if (!layer.hasDescendantNeedingCompositingRequirementsTraversal()
&& !layer.needsCompositingRequirementsTraversal()
&& !compositingState.fullPaintOrderTraversalRequired
&& !compositingState.descendantsRequireCompositingUpdate) {
traverseUnchangedSubtree(ancestorLayer, layer, overlapMap, compositingState, backingSharingState, descendantHas3DTransform);
return;
}
LOG_WITH_STREAM(Compositing, stream << TextStream::Repeat(compositingState.depth * 2, ' ') << &layer << (layer.isNormalFlowOnly() ? " n" : " s") << " computeCompositingRequirements (backing provider candidate " << backingSharingState.backingProviderCandidate() << ")");
// FIXME: maybe we can avoid updating all remaining layers in paint order.
compositingState.fullPaintOrderTraversalRequired |= layer.needsCompositingRequirementsTraversal();
compositingState.descendantsRequireCompositingUpdate |= layer.descendantsNeedCompositingRequirementsTraversal();
layer.setHasCompositingDescendant(false);
// We updated compositing for direct reasons in layerStyleChanged(). Here, check for compositing that can only be evaluated after layout.
RequiresCompositingData queryData;
bool willBeComposited = layer.isComposited();
bool becameCompositedAfterDescendantTraversal = false;
IndirectCompositingReason compositingReason = compositingState.subtreeIsCompositing ? IndirectCompositingReason::Stacking : IndirectCompositingReason::None;
if (layer.needsPostLayoutCompositingUpdate() || compositingState.fullPaintOrderTraversalRequired || compositingState.descendantsRequireCompositingUpdate) {
layer.setIndirectCompositingReason(IndirectCompositingReason::None);
willBeComposited = needsToBeComposited(layer, queryData);
}
bool layerPaintsIntoProvidedBacking = false;
if (!willBeComposited && compositingState.subtreeIsCompositing && canBeComposited(layer) && backingSharingState.canIncludeLayer(layer)) {
backingSharingState.appendSharingLayer(layer);
LOG_WITH_STREAM(Compositing, stream << " layer " << &layer << " can share with " << backingSharingState.backingProviderCandidate());
compositingReason = IndirectCompositingReason::None;
layerPaintsIntoProvidedBacking = true;
}
compositingState.fullPaintOrderTraversalRequired |= layer.subsequentLayersNeedCompositingRequirementsTraversal();
OverlapExtent layerExtent;
// Use the fact that we're composited as a hint to check for an animating transform.
// FIXME: Maybe needsToBeComposited() should return a bitmask of reasons, to avoid the need to recompute things.
if (willBeComposited && !layer.isRenderViewLayer())
layerExtent.hasTransformAnimation = isRunningTransformAnimation(layer.renderer());
bool respectTransforms = !layerExtent.hasTransformAnimation;
overlapMap.geometryMap().pushMappingsToAncestor(&layer, ancestorLayer, respectTransforms);
// If we know for sure the layer is going to be composited, don't bother looking it up in the overlap map
if (!willBeComposited && !layerPaintsIntoProvidedBacking && !overlapMap.isEmpty() && compositingState.testingOverlap) {
// If we're testing for overlap, we only need to composite if we overlap something that is already composited.
if (layerOverlaps(overlapMap, layer, layerExtent))
compositingReason = IndirectCompositingReason::Overlap;
else
compositingReason = IndirectCompositingReason::None;
}
#if ENABLE(VIDEO)
// Video is special. It's the only RenderLayer type that can both have
// RenderLayer children and whose children can't use its backing to render
// into. These children (the controls) always need to be promoted into their
// own layers to draw on top of the accelerated video.
if (compositingState.compositingAncestor && compositingState.compositingAncestor->renderer().isVideo())
compositingReason = IndirectCompositingReason::Overlap;
#endif
if (compositingReason != IndirectCompositingReason::None)
layer.setIndirectCompositingReason(compositingReason);
// Check if the computed indirect reason will force the layer to become composited.
if (!willBeComposited && layer.mustCompositeForIndirectReasons() && canBeComposited(layer)) {
LOG_WITH_STREAM(Compositing, stream << "layer " << &layer << " compositing for indirect reason " << layer.indirectCompositingReason() << " (was sharing: " << layerPaintsIntoProvidedBacking << ")");
willBeComposited = true;
layerPaintsIntoProvidedBacking = false;
}
// 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 subtreeIsCompositing set to false.
CompositingState currentState = compositingState.stateForPaintOrderChildren(layer);
bool didPushOverlapContainer = false;
auto layerWillComposite = [&] {
// This layer is going to be composited, so children can safely ignore the fact that there's an
// animation running behind this layer, meaning they can rely on the overlap map testing again.
currentState.testingOverlap = true;
// This layer now acts as the ancestor for kids.
currentState.compositingAncestor = &layer;
// Compositing turns off backing sharing.
currentState.backingSharingAncestor = nullptr;
if (layerPaintsIntoProvidedBacking) {
layerPaintsIntoProvidedBacking = false;
// layerPaintsIntoProvidedBacking was only true for layers that would otherwise composite because of overlap. If we can
// no longer share, put this this indirect reason back on the layer so that requiresOwnBackingStore() sees it.
layer.setIndirectCompositingReason(IndirectCompositingReason::Overlap);
LOG_WITH_STREAM(Compositing, stream << "layer " << &layer << " was sharing now will composite");
} else {
if (!didPushOverlapContainer) {
overlapMap.pushCompositingContainer(layer);
didPushOverlapContainer = true;
LOG_WITH_STREAM(CompositingOverlap, stream << "layer " << &layer << " will composite, pushed container " << overlapMap);
}
}
willBeComposited = true;
};
auto layerWillCompositePostDescendants = [&] {
layerWillComposite();
currentState.subtreeIsCompositing = true;
becameCompositedAfterDescendantTraversal = true;
};
if (willBeComposited) {
layerWillComposite();
computeExtent(overlapMap, layer, layerExtent);
currentState.ancestorHasTransformAnimation |= layerExtent.hasTransformAnimation;
// Too hard to compute animated bounds if both us and some ancestor is animating transform.
layerExtent.animationCausesExtentUncertainty |= layerExtent.hasTransformAnimation && compositingState.ancestorHasTransformAnimation;
} else if (layerPaintsIntoProvidedBacking) {
currentState.backingSharingAncestor = &layer;
overlapMap.pushCompositingContainer(layer);
didPushOverlapContainer = true;
LOG_WITH_STREAM(CompositingOverlap, stream << "layer " << &layer << " will share, pushed container " << overlapMap);
}
auto preDescendantProviderCandidate = backingSharingState.updateBeforeDescendantTraversal(layer, willBeComposited);
#if ASSERT_ENABLED
LayerListMutationDetector mutationChecker(layer);
#endif
bool anyDescendantHas3DTransform = false;
bool descendantsAddedToOverlap = currentState.hasNonRootCompositedAncestor();
if (layer.hasNegativeZOrderLayers()) {
// Speculatively push this layer onto the overlap map.
bool didSpeculativelyPushOverlapContainer = false;
if (!didPushOverlapContainer) {
overlapMap.pushCompositingContainer(layer);
didPushOverlapContainer = true;
didSpeculativelyPushOverlapContainer = true;
}
bool compositeForNegativeZOrderDescendant = false;
for (auto* childLayer : layer.negativeZOrderLayers()) {
computeCompositingRequirements(&layer, *childLayer, overlapMap, currentState, backingSharingState, anyDescendantHas3DTransform);
// 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 && currentState.subtreeIsCompositing) {
layer.setIndirectCompositingReason(IndirectCompositingReason::BackgroundLayer);
layerWillComposite();
compositeForNegativeZOrderDescendant = true;
}
}
if (!compositeForNegativeZOrderDescendant && didSpeculativelyPushOverlapContainer) {
overlapMap.popCompositingContainer(layer);
didPushOverlapContainer = false;
}
}
for (auto* childLayer : layer.normalFlowLayers())
computeCompositingRequirements(&layer, *childLayer, overlapMap, currentState, backingSharingState, anyDescendantHas3DTransform);
for (auto* childLayer : layer.positiveZOrderLayers())
computeCompositingRequirements(&layer, *childLayer, overlapMap, currentState, backingSharingState, anyDescendantHas3DTransform);
// Set the flag to say that this layer has compositing children.
layer.setHasCompositingDescendant(currentState.subtreeIsCompositing);
layer.setHasCompositedNonContainedDescendants(currentState.hasCompositedNonContainedDescendants);
// If we just entered compositing mode, the root will have become composited (as long as accelerated compositing is enabled).
if (layer.isRenderViewLayer()) {
if (usesCompositing() && m_hasAcceleratedCompositing)
willBeComposited = true;
}
#if ENABLE(CSS_COMPOSITING)
bool isolatedCompositedBlending = layer.isolatesCompositedBlending();
layer.setHasNotIsolatedCompositedBlendingDescendants(currentState.hasNotIsolatedCompositedBlendingDescendants);
if (layer.isolatesCompositedBlending() != isolatedCompositedBlending) {
// isolatedCompositedBlending affects the result of clippedByAncestor().
layer.setChildrenNeedCompositingGeometryUpdate();
}
ASSERT(!layer.hasNotIsolatedCompositedBlendingDescendants() || layer.hasNotIsolatedBlendingDescendants());
#endif
// Now check for reasons to become composited that depend on the state of descendant layers.
if (!willBeComposited && canBeComposited(layer)) {
auto indirectReason = computeIndirectCompositingReason(layer, currentState.subtreeIsCompositing, anyDescendantHas3DTransform, layerPaintsIntoProvidedBacking);
if (indirectReason != IndirectCompositingReason::None) {
layer.setIndirectCompositingReason(indirectReason);
layerWillCompositePostDescendants();
}
}
if (layer.reflectionLayer()) {
// FIXME: Shouldn't we call computeCompositingRequirements to handle a reflection overlapping with another renderer?
layer.reflectionLayer()->setIndirectCompositingReason(willBeComposited ? IndirectCompositingReason::Stacking : IndirectCompositingReason::None);
}
// 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. However, don't drop out of compositing mode
// if there are composited layers that we didn't hit in our traversal (e.g. because of visibility:hidden).
RequiresCompositingData rootLayerQueryData;
if (layer.isRenderViewLayer() && !currentState.subtreeIsCompositing && !requiresCompositingLayer(layer, rootLayerQueryData) && !m_forceCompositingMode && !needsCompositingForContentOrOverlays()) {
// Don't drop out of compositing on iOS, because we may flash. See <rdar://problem/8348337>.
#if !PLATFORM(IOS_FAMILY)
enableCompositingMode(false);
willBeComposited = false;
#endif
}
ASSERT(willBeComposited == needsToBeComposited(layer, queryData));
// Create or destroy backing here. However, we can't update geometry because layers above us may become composited
// during post-order traversal (e.g. for clipping).
if (updateBacking(layer, queryData, &backingSharingState, willBeComposited ? BackingRequired::Yes : BackingRequired::No)) {
layer.setNeedsCompositingLayerConnection();
// Child layers need to get a geometry update to recompute their position.
layer.setChildrenNeedCompositingGeometryUpdate();
// The composited bounds of enclosing layers depends on which descendants are composited, so they need a geometry update.
layer.setNeedsCompositingGeometryUpdateOnAncestors();
}
// Update layer state bits.
if (layer.reflectionLayer() && updateLayerCompositingState(*layer.reflectionLayer(), &layer, queryData, backingSharingState))
layer.setNeedsCompositingLayerConnection();
// FIXME: clarify needsCompositingPaintOrderChildrenUpdate. If a composited layer gets a new ancestor, it needs geometry computations.
if (layer.needsCompositingPaintOrderChildrenUpdate()) {
layer.setChildrenNeedCompositingGeometryUpdate();
layer.setNeedsCompositingLayerConnection();
}
layer.clearCompositingRequirementsTraversalState();
// Compute state passed to the caller.
descendantHas3DTransform |= anyDescendantHas3DTransform || layer.has3DTransform();
compositingState.updateWithDescendantStateAndLayer(currentState, layer, ancestorLayer, layerExtent);
backingSharingState.updateAfterDescendantTraversal(layer, preDescendantProviderCandidate, compositingState.stackingContextAncestor);
bool layerContributesToOverlap = (currentState.compositingAncestor && !currentState.compositingAncestor->isRenderViewLayer()) || currentState.backingSharingAncestor;
updateOverlapMap(overlapMap, layer, layerExtent, didPushOverlapContainer, layerContributesToOverlap, becameCompositedAfterDescendantTraversal && !descendantsAddedToOverlap);
if (layer.isComposited())
layer.backing()->updateAllowsBackingStoreDetaching(layerExtent.bounds);
overlapMap.geometryMap().popMappingsToAncestor(ancestorLayer);
LOG_WITH_STREAM(Compositing, stream << TextStream::Repeat(compositingState.depth * 2, ' ') << &layer << " computeCompositingRequirements - willBeComposited " << willBeComposited << " (backing provider candidate " << backingSharingState.backingProviderCandidate() << ")");
}
// We have to traverse unchanged layers to fill in the overlap map.
void RenderLayerCompositor::traverseUnchangedSubtree(RenderLayer* ancestorLayer, RenderLayer& layer, LayerOverlapMap& overlapMap, CompositingState& compositingState, BackingSharingState& backingSharingState, bool& descendantHas3DTransform)
{
layer.updateDescendantDependentFlags();
layer.updateLayerListsIfNeeded();
ASSERT(!compositingState.fullPaintOrderTraversalRequired);
ASSERT(!layer.hasDescendantNeedingCompositingRequirementsTraversal());
ASSERT(!layer.needsCompositingRequirementsTraversal());
LOG_WITH_STREAM(Compositing, stream << TextStream::Repeat(compositingState.depth * 2, ' ') << &layer << (layer.isNormalFlowOnly() ? " n" : " s") << " traverseUnchangedSubtree");
bool layerIsComposited = layer.isComposited();
bool layerPaintsIntoProvidedBacking = false;
bool didPushOverlapContainer = false;
OverlapExtent layerExtent;
if (layerIsComposited && !layer.isRenderViewLayer())
layerExtent.hasTransformAnimation = isRunningTransformAnimation(layer.renderer());
bool respectTransforms = !layerExtent.hasTransformAnimation;
overlapMap.geometryMap().pushMappingsToAncestor(&layer, ancestorLayer, respectTransforms);
// If we know for sure the layer is going to be composited, don't bother looking it up in the overlap map
if (!layerIsComposited && !overlapMap.isEmpty() && compositingState.testingOverlap)
computeExtent(overlapMap, layer, layerExtent);
if (layer.paintsIntoProvidedBacking()) {
ASSERT(backingSharingState.canIncludeLayer(layer));
backingSharingState.appendSharingLayer(layer);
layerPaintsIntoProvidedBacking = true;
}
CompositingState currentState = compositingState.stateForPaintOrderChildren(layer);
if (layerIsComposited) {
// This layer is going to be composited, so children can safely ignore the fact that there's an
// animation running behind this layer, meaning they can rely on the overlap map testing again.
currentState.testingOverlap = true;
// This layer now acts as the ancestor for kids.
currentState.compositingAncestor = &layer;
currentState.backingSharingAncestor = nullptr;
overlapMap.pushCompositingContainer(layer);
didPushOverlapContainer = true;
LOG_WITH_STREAM(CompositingOverlap, stream << "unchangedSubtree: layer " << &layer << " will composite, pushed container " << overlapMap);
computeExtent(overlapMap, layer, layerExtent);
currentState.ancestorHasTransformAnimation |= layerExtent.hasTransformAnimation;
// Too hard to compute animated bounds if both us and some ancestor is animating transform.
layerExtent.animationCausesExtentUncertainty |= layerExtent.hasTransformAnimation && compositingState.ancestorHasTransformAnimation;
} else if (layerPaintsIntoProvidedBacking) {
overlapMap.pushCompositingContainer(layer);
currentState.backingSharingAncestor = &layer;
didPushOverlapContainer = true;
LOG_WITH_STREAM(CompositingOverlap, stream << "unchangedSubtree: layer " << &layer << " will share, pushed container " << overlapMap);
}
auto preDescendantProviderCandidate = backingSharingState.updateBeforeDescendantTraversal(layer, layerIsComposited);
#if ASSERT_ENABLED
LayerListMutationDetector mutationChecker(layer);
#endif
bool anyDescendantHas3DTransform = false;
for (auto* childLayer : layer.negativeZOrderLayers()) {
traverseUnchangedSubtree(&layer, *childLayer, overlapMap, currentState, backingSharingState, anyDescendantHas3DTransform);
if (currentState.subtreeIsCompositing)
ASSERT(layerIsComposited);
}
for (auto* childLayer : layer.normalFlowLayers())
traverseUnchangedSubtree(&layer, *childLayer, overlapMap, currentState, backingSharingState, anyDescendantHas3DTransform);
for (auto* childLayer : layer.positiveZOrderLayers())
traverseUnchangedSubtree(&layer, *childLayer, overlapMap, currentState, backingSharingState, anyDescendantHas3DTransform);
// Set the flag to say that this layer has compositing children.
ASSERT(layer.hasCompositingDescendant() == currentState.subtreeIsCompositing);
ASSERT_IMPLIES(canBeComposited(layer) && clipsCompositingDescendants(layer), layerIsComposited);
descendantHas3DTransform |= anyDescendantHas3DTransform || layer.has3DTransform();
ASSERT(!currentState.fullPaintOrderTraversalRequired);
compositingState.updateWithDescendantStateAndLayer(currentState, layer, ancestorLayer, layerExtent, true);
backingSharingState.updateAfterDescendantTraversal(layer, preDescendantProviderCandidate, compositingState.stackingContextAncestor);
bool layerContributesToOverlap = (currentState.compositingAncestor && !currentState.compositingAncestor->isRenderViewLayer()) || currentState.backingSharingAncestor;
updateOverlapMap(overlapMap, layer, layerExtent, didPushOverlapContainer, layerContributesToOverlap);
overlapMap.geometryMap().popMappingsToAncestor(ancestorLayer);
ASSERT(!layer.needsCompositingRequirementsTraversal());
}
void RenderLayerCompositor::updateBackingAndHierarchy(RenderLayer& layer, Vector<Ref<GraphicsLayer>>& childLayersOfEnclosingLayer, UpdateBackingTraversalState& traversalState, ScrollingTreeState& scrollingTreeState, OptionSet<UpdateLevel> updateLevel)
{
layer.updateDescendantDependentFlags();
layer.updateLayerListsIfNeeded();
bool layerNeedsUpdate = !updateLevel.isEmpty();
if (layer.descendantsNeedUpdateBackingAndHierarchyTraversal())
updateLevel.add(UpdateLevel::AllDescendants);
ScrollingTreeState scrollingStateForDescendants = scrollingTreeState;
UpdateBackingTraversalState traversalStateForDescendants = traversalState.stateForDescendants();
Vector<RenderLayer*> layersClippedByScrollers;
Vector<RenderLayer*> compositedOverflowScrollLayers;
if (layer.needsScrollingTreeUpdate())
scrollingTreeState.needSynchronousScrollingReasonsUpdate = true;
auto* layerBacking = layer.backing();
if (layerBacking) {
updateLevel.remove(UpdateLevel::CompositedChildren);
// We updated the composited bounds in RenderLayerBacking::updateAfterLayout(), but it may have changed
// based on which descendants are now composited.
if (layerBacking->updateCompositedBounds()) {
layer.setNeedsCompositingGeometryUpdate();
// Our geometry can affect descendants.
updateLevel.add(UpdateLevel::CompositedChildren);
}
if (layerNeedsUpdate || layer.needsCompositingConfigurationUpdate()) {
if (layerBacking->updateConfiguration(traversalState.compositingAncestor)) {
layerNeedsUpdate = true; // We also need to update geometry.
layer.setNeedsCompositingLayerConnection();
}
layerBacking->updateDebugIndicators(m_showDebugBorders, m_showRepaintCounter);
}
OptionSet<ScrollingNodeChangeFlags> scrollingNodeChanges = { ScrollingNodeChangeFlags::Layer };
if (layerNeedsUpdate || layer.needsCompositingGeometryUpdate()) {
layerBacking->updateGeometry(traversalState.compositingAncestor);
scrollingNodeChanges.add(ScrollingNodeChangeFlags::LayerGeometry);
} else if (layer.needsScrollingTreeUpdate())
scrollingNodeChanges.add(ScrollingNodeChangeFlags::LayerGeometry);
if (auto* reflection = layer.reflectionLayer()) {
if (auto* reflectionBacking = reflection->backing()) {
reflectionBacking->updateCompositedBounds();
reflectionBacking->updateGeometry(&layer);
reflectionBacking->updateAfterDescendants();
}
}
if (!layer.parent())
updateRootLayerPosition();
// FIXME: do based on dirty flags. Need to do this for changes of geometry, configuration and hierarchy.
// Need to be careful to do the right thing when a scroll-coordinated layer loses a scroll-coordinated ancestor.
scrollingStateForDescendants.parentNodeID = updateScrollCoordinationForLayer(layer, traversalState.compositingAncestor, scrollingTreeState, scrollingNodeChanges);
scrollingStateForDescendants.nextChildIndex = 0;
traversalStateForDescendants.compositingAncestor = &layer;
traversalStateForDescendants.layersClippedByScrollers = &layersClippedByScrollers;
traversalStateForDescendants.overflowScrollLayers = &compositedOverflowScrollLayers;
#if !LOG_DISABLED
logLayerInfo(layer, "updateBackingAndHierarchy", traversalState.depth);
#endif
}
if (layer.childrenNeedCompositingGeometryUpdate())
updateLevel.add(UpdateLevel::CompositedChildren);
// If this layer has backing, then we are collecting its children, otherwise appending
// to the compositing child list of an enclosing layer.
Vector<Ref<GraphicsLayer>> layerChildren;
auto& childList = layerBacking ? layerChildren : childLayersOfEnclosingLayer;
bool requireDescendantTraversal = layer.hasDescendantNeedingUpdateBackingOrHierarchyTraversal()
|| (layer.hasCompositingDescendant() && (!layerBacking || layer.needsCompositingLayerConnection() || !updateLevel.isEmpty()));
bool requiresChildRebuild = layerBacking && layer.needsCompositingLayerConnection() && !layer.hasCompositingDescendant();
#if ASSERT_ENABLED
LayerListMutationDetector mutationChecker(layer);
#endif
auto appendForegroundLayerIfNecessary = [&] {
// If a negative z-order child is compositing, we get a foreground layer which needs to get parented.
if (layer.negativeZOrderLayers().size()) {
if (layerBacking && layerBacking->foregroundLayer())
childList.append(*layerBacking->foregroundLayer());
}
};
if (requireDescendantTraversal) {
for (auto* renderLayer : layer.negativeZOrderLayers())
updateBackingAndHierarchy(*renderLayer, childList, traversalStateForDescendants, scrollingStateForDescendants, updateLevel);
appendForegroundLayerIfNecessary();
for (auto* renderLayer : layer.normalFlowLayers())
updateBackingAndHierarchy(*renderLayer, childList, traversalStateForDescendants, scrollingStateForDescendants, updateLevel);
for (auto* renderLayer : layer.positiveZOrderLayers())
updateBackingAndHierarchy(*renderLayer, childList, traversalStateForDescendants, scrollingStateForDescendants, updateLevel);
// Pass needSynchronousScrollingReasonsUpdate back up.
scrollingTreeState.needSynchronousScrollingReasonsUpdate |= scrollingStateForDescendants.needSynchronousScrollingReasonsUpdate;
if (scrollingTreeState.parentNodeID == scrollingStateForDescendants.parentNodeID)
scrollingTreeState.nextChildIndex = scrollingStateForDescendants.nextChildIndex;
} else if (requiresChildRebuild)
appendForegroundLayerIfNecessary();
if (layerBacking) {
if (requireDescendantTraversal || requiresChildRebuild) {
bool parented = false;
if (is<RenderWidget>(layer.renderer()))
parented = parentFrameContentLayers(downcast<RenderWidget>(layer.renderer()));
if (!parented) {
// If the layer has a clipping layer the overflow controls layers will be siblings of the clipping layer.
// Otherwise, the overflow control layers are normal children.
if (!layerBacking->hasClippingLayer() && !layerBacking->hasScrollingLayer()) {
if (auto* overflowControlLayer = layerBacking->overflowControlsContainer())
layerChildren.append(*overflowControlLayer);
}
adjustOverflowScrollbarContainerLayers(layer, compositedOverflowScrollLayers, layersClippedByScrollers, layerChildren);
layerBacking->parentForSublayers()->setChildren(WTFMove(layerChildren));
}
}
childLayersOfEnclosingLayer.append(*layerBacking->childForSuperlayers());
if (layerBacking->hasAncestorClippingLayers() && layerBacking->ancestorClippingStack()->hasAnyScrollingLayers())
traversalState.layersClippedByScrollers->append(&layer);
if (layer.hasCompositedScrollableOverflow())
traversalState.overflowScrollLayers->append(&layer);
layerBacking->updateAfterDescendants();
}
layer.clearUpdateBackingOrHierarchyTraversalState();
}
// Finds the set of overflow:scroll layers whose overflow controls hosting layer needs to be reparented,
// to ensure that the scrollbars show on top of positioned content inside the scroller.
void RenderLayerCompositor::adjustOverflowScrollbarContainerLayers(RenderLayer& stackingContextLayer, const Vector<RenderLayer*>& overflowScrollLayers, const Vector<RenderLayer*>& layersClippedByScrollers, Vector<Ref<GraphicsLayer>>& layerChildren)
{
if (layersClippedByScrollers.isEmpty())
return;
HashMap<RenderLayer*, RenderLayer*> overflowScrollToLastContainedLayerMap;
for (auto* clippedLayer : layersClippedByScrollers) {
auto* clippingStack = clippedLayer->backing()->ancestorClippingStack();
for (const auto& stackEntry : clippingStack->stack()) {
if (!stackEntry.clipData.isOverflowScroll)
continue;
if (auto* layer = stackEntry.clipData.clippingLayer.get())
overflowScrollToLastContainedLayerMap.set(layer, clippedLayer);
}
}
for (auto* overflowScrollingLayer : overflowScrollLayers) {
auto it = overflowScrollToLastContainedLayerMap.find(overflowScrollingLayer);
if (it == overflowScrollToLastContainedLayerMap.end())
continue;
auto* lastContainedDescendant = it->value;
if (!lastContainedDescendant || !lastContainedDescendant->isComposited())
continue;
auto* lastContainedDescendantBacking = lastContainedDescendant->backing();
auto* overflowBacking = overflowScrollingLayer->backing();
if (!overflowBacking)
continue;
auto* overflowContainerLayer = overflowBacking->overflowControlsContainer();
if (!overflowContainerLayer)
continue;
overflowContainerLayer->removeFromParent();
if (overflowBacking->hasAncestorClippingLayers())
overflowBacking->ensureOverflowControlsHostLayerAncestorClippingStack(&stackingContextLayer);
if (auto* overflowControlsAncestorClippingStack = overflowBacking->overflowControlsHostLayerAncestorClippingStack()) {
overflowControlsAncestorClippingStack->lastClippingLayer()->setChildren({ Ref { *overflowContainerLayer } });
overflowContainerLayer = overflowControlsAncestorClippingStack->firstClippingLayer();
}
auto* lastDescendantGraphicsLayer = lastContainedDescendantBacking->childForSuperlayers();
auto* overflowScrollerGraphicsLayer = overflowBacking->childForSuperlayers();
std::optional<size_t> lastDescendantLayerIndex;
std::optional<size_t> scrollerLayerIndex;
for (size_t i = 0; i < layerChildren.size(); ++i) {
const auto* graphicsLayer = layerChildren[i].ptr();
if (graphicsLayer == lastDescendantGraphicsLayer)
lastDescendantLayerIndex = i;
else if (graphicsLayer == overflowScrollerGraphicsLayer)
scrollerLayerIndex = i;
}
if (lastDescendantLayerIndex && scrollerLayerIndex) {
auto insertionIndex = std::max(lastDescendantLayerIndex.value() + 1, scrollerLayerIndex.value() + 1);
LOG_WITH_STREAM(Compositing, stream << "Moving overflow controls layer for " << overflowScrollingLayer << " to appear after " << lastContainedDescendant);
layerChildren.insert(insertionIndex, *overflowContainerLayer);
}
overflowBacking->adjustOverflowControlsPositionRelativeToAncestor(stackingContextLayer);
}
}
void RenderLayerCompositor::appendDocumentOverlayLayers(Vector<Ref<GraphicsLayer>>& childList)
{
if (!isMainFrameCompositor() || !m_compositing)
return;
if (!page().pageOverlayController().hasDocumentOverlays())
return;
Ref<GraphicsLayer> overlayHost = page().pageOverlayController().layerWithDocumentOverlays();
childList.append(WTFMove(overlayHost));
}
bool RenderLayerCompositor::needsCompositingForContentOrOverlays() const
{
return m_contentLayersCount + page().pageOverlayController().overlayCount();
}
void RenderLayerCompositor::layerBecameComposited(const RenderLayer& layer)
{
if (&layer != m_renderView.layer())
++m_contentLayersCount;
}
void RenderLayerCompositor::layerBecameNonComposited(const RenderLayer& layer)
{
// Inform the inspector that the given RenderLayer was destroyed.
// FIXME: "destroyed" is a misnomer.
InspectorInstrumentation::renderLayerDestroyed(&page(), layer);
if (&layer != m_renderView.layer()) {
ASSERT(m_contentLayersCount > 0);
--m_contentLayersCount;
}
}
#if !LOG_DISABLED
void RenderLayerCompositor::logLayerInfo(const RenderLayer& layer, const char* phase, int depth)
{
if (!compositingLogEnabled())
return;
auto* backing = layer.backing();
RequiresCompositingData queryData;
if (requiresCompositingLayer(layer, queryData) || layer.isRenderViewLayer()) {
++m_obligateCompositedLayerCount;
m_obligatoryBackingStoreBytes += backing->backingStoreMemoryEstimate();
} else {
++m_secondaryCompositedLayerCount;
m_secondaryBackingStoreBytes += backing->backingStoreMemoryEstimate();
}
LayoutRect absoluteBounds = backing->compositedBounds();
absoluteBounds.move(layer.offsetFromAncestor(m_renderView.layer()));
StringBuilder logString;
logString.append(pad(' ', 12 + depth * 2, hex(reinterpret_cast<uintptr_t>(&layer), Lowercase)), " id ", backing->graphicsLayer()->primaryLayerID(), " (", absoluteBounds.x().toFloat(), ',', absoluteBounds.y().toFloat(), '-', absoluteBounds.maxX().toFloat(), ',', absoluteBounds.maxY().toFloat(), ") ", FormattedNumber::fixedWidth(backing->backingStoreMemoryEstimate() / 1024, 2), "KB");
if (!layer.renderer().style().hasAutoUsedZIndex())
logString.append(" z-index: ", layer.renderer().style().usedZIndex());
logString.append(" (", logOneReasonForCompositing(layer), ") ");
if (backing->graphicsLayer()->contentsOpaque() || backing->paintsIntoCompositedAncestor() || backing->foregroundLayer() || backing->backgroundLayer()) {
logString.append('[');
const char* prefix = "";
if (backing->graphicsLayer()->contentsOpaque()) {
logString.append("opaque");
prefix = ", ";
}
if (backing->paintsIntoCompositedAncestor()) {
logString.append(prefix, "paints into ancestor");
prefix = ", ";
}
if (backing->foregroundLayer() || backing->backgroundLayer()) {
if (backing->foregroundLayer() && backing->backgroundLayer()) {
logString.append(prefix, "+foreground+background");
prefix = ", ";
} else if (backing->foregroundLayer()) {
logString.append(prefix, "+foreground");
prefix = ", ";
} else {
logString.append(prefix, "+background");
prefix = ", ";
}
}
if (backing->paintsSubpixelAntialiasedText())
logString.append(prefix, "texty");
logString.append("] ");
}
logString.append(layer.name(), " - ", phase);
LOG(Compositing, "%s", logString.toString().utf8().data());
}
#endif
static bool clippingChanged(const RenderStyle& oldStyle, const RenderStyle& newStyle)
{
return oldStyle.overflowX() != newStyle.overflowX() || oldStyle.overflowY() != newStyle.overflowY()
|| oldStyle.hasClip() != newStyle.hasClip() || oldStyle.clip() != newStyle.clip();
}
static bool styleAffectsLayerGeometry(const RenderStyle& style)
{
return style.hasClip() || style.clipPath() || style.hasBorderRadius();
}
static bool recompositeChangeRequiresGeometryUpdate(const RenderStyle& oldStyle, const RenderStyle& newStyle)
{
return oldStyle.transform() != newStyle.transform()
|| oldStyle.translate() != newStyle.translate()
|| oldStyle.scale() != newStyle.scale()
|| oldStyle.rotate() != newStyle.rotate()
|| oldStyle.transformBox() != newStyle.transformBox()
|| oldStyle.transformOriginX() != newStyle.transformOriginX()
|| oldStyle.transformOriginY() != newStyle.transformOriginY()
|| oldStyle.transformOriginZ() != newStyle.transformOriginZ()
|| oldStyle.usedTransformStyle3D() != newStyle.usedTransformStyle3D()
|| oldStyle.perspective() != newStyle.perspective()
|| oldStyle.perspectiveOriginX() != newStyle.perspectiveOriginX()
|| oldStyle.perspectiveOriginY() != newStyle.perspectiveOriginY()
|| oldStyle.backfaceVisibility() != newStyle.backfaceVisibility()
|| !arePointingToEqualData(oldStyle.offsetPath(), newStyle.offsetPath())
|| oldStyle.offsetAnchor() != newStyle.offsetAnchor()
|| oldStyle.offsetPosition() != newStyle.offsetPosition()
|| oldStyle.offsetDistance() != newStyle.offsetDistance()
|| oldStyle.offsetRotate() != newStyle.offsetRotate()
|| !arePointingToEqualData(oldStyle.clipPath(), newStyle.clipPath())
|| oldStyle.overscrollBehaviorX() != newStyle.overscrollBehaviorX()
|| oldStyle.overscrollBehaviorY() != newStyle.overscrollBehaviorY();
}
void RenderLayerCompositor::layerStyleChanged(StyleDifference diff, RenderLayer& layer, const RenderStyle* oldStyle)
{
if (diff == StyleDifference::Equal)
return;
// Create or destroy backing here so that code that runs during layout can reliably use isComposited() (though this
// is only true for layers composited for direct reasons).
// Also, it allows us to avoid a tree walk in updateCompositingLayers() when no layer changed its compositing state.
RequiresCompositingData queryData;
queryData.layoutUpToDate = LayoutUpToDate::No;
bool layerChanged = updateBacking(layer, queryData);
if (layerChanged) {
layer.setChildrenNeedCompositingGeometryUpdate();
layer.setNeedsCompositingLayerConnection();
layer.setSubsequentLayersNeedCompositingRequirementsTraversal();
// Ancestor layers that composited for indirect reasons (things listed in styleChangeMayAffectIndirectCompositingReasons()) need to get updated.
// This could be optimized by only setting this flag on layers with the relevant styles.
layer.setNeedsPostLayoutCompositingUpdateOnAncestors();
}
if (queryData.reevaluateAfterLayout)
layer.setNeedsPostLayoutCompositingUpdate();
const auto& newStyle = layer.renderer().style();
if (hasContentCompositingLayers()) {
if (diff >= StyleDifference::LayoutPositionedMovementOnly) {
layer.setNeedsPostLayoutCompositingUpdate();
layer.setNeedsCompositingGeometryUpdate();
}
if (diff >= StyleDifference::Layout) {
// FIXME: only set flags here if we know we have a composited descendant, but we might not know at this point.
if (oldStyle && clippingChanged(*oldStyle, newStyle)) {
if (layer.isStackingContext()) {
layer.setNeedsPostLayoutCompositingUpdate(); // Layer needs to become composited if it has composited descendants.
layer.setNeedsCompositingConfigurationUpdate(); // If already composited, layer needs to create/destroy clipping layer.
layer.setChildrenNeedCompositingGeometryUpdate(); // Clipping layers on this layer affect descendant layer geometry.
} else {
// Descendant (in containing block order) compositing layers need to re-evaluate their clipping,
// but they might be siblings in z-order so go up to our stacking context.
if (auto* stackingContext = layer.stackingContext())
stackingContext->setDescendantsNeedUpdateBackingAndHierarchyTraversal();
}
}
// These properties trigger compositing if some descendant is composited.
if (oldStyle && styleChangeMayAffectIndirectCompositingReasons(*oldStyle, newStyle))
layer.setNeedsPostLayoutCompositingUpdate();
layer.setNeedsCompositingGeometryUpdate();
}
}
auto* backing = layer.backing();
if (!backing)
return;
backing->updateConfigurationAfterStyleChange();
if (diff >= StyleDifference::Repaint) {
// Visibility change may affect geometry of the enclosing composited layer.
if (oldStyle && oldStyle->visibility() != newStyle.visibility())
layer.setNeedsCompositingGeometryUpdate();
// We'll get a diff of Repaint when things like clip-path change; these might affect layer or inner-layer geometry.
if (layer.isComposited() && oldStyle) {
if (styleAffectsLayerGeometry(*oldStyle) || styleAffectsLayerGeometry(newStyle))
layer.setNeedsCompositingGeometryUpdate();
}
}
if (diff >= StyleDifference::RecompositeLayer) {
if (layer.isComposited()) {
bool hitTestingStateChanged = oldStyle && (oldStyle->effectivePointerEvents() != newStyle.effectivePointerEvents());
if (is<RenderWidget>(layer.renderer()) || hitTestingStateChanged) {
// For RenderWidgets this is necessary to get iframe layers hooked up in response to scheduleInvalidateStyleAndLayerComposition().
layer.setNeedsCompositingConfigurationUpdate();
}
}
if (oldStyle && recompositeChangeRequiresGeometryUpdate(*oldStyle, newStyle)) {
// FIXME: transform changes really need to trigger layout. See RenderElement::adjustStyleDifference().
layer.setNeedsPostLayoutCompositingUpdate();
layer.setNeedsCompositingGeometryUpdate();
}
}
}
bool RenderLayerCompositor::needsCompositingUpdateForStyleChangeOnNonCompositedLayer(RenderLayer& layer, const RenderStyle* oldStyle) const
{
// Needed for scroll bars.
if (layer.isRenderViewLayer())
return true;
if (!oldStyle)
return false;
const RenderStyle& newStyle = layer.renderer().style();
// Visibility change may affect geometry of the enclosing composited layer.
if (oldStyle->visibility() != newStyle.visibility())
return true;
// We don't have any direct reasons for this style change to affect layer composition. Test if it might affect things indirectly.
if (styleChangeMayAffectIndirectCompositingReasons(*oldStyle, newStyle))
return true;
return false;
}
// FIXME: remove and never ask questions about reflection layers.
static RenderLayerModelObject& rendererForCompositingTests(const RenderLayer& layer)
{
auto* renderer = &layer.renderer();
// The compositing state of a reflection should match that of its reflected layer.
if (layer.isReflection())
renderer = downcast<RenderLayerModelObject>(renderer->parent()); // The RenderReplica's parent is the object being reflected.
return *renderer;
}
void RenderLayerCompositor::updateRootContentLayerClipping()
{
m_rootContentsLayer->setMasksToBounds(!m_renderView.settings().backgroundShouldExtendBeyondPage());
}
bool RenderLayerCompositor::updateBacking(RenderLayer& layer, RequiresCompositingData& queryData, BackingSharingState* backingSharingState, BackingRequired backingRequired)
{
bool layerChanged = false;
if (backingRequired == BackingRequired::Unknown)
backingRequired = needsToBeComposited(layer, queryData) ? BackingRequired::Yes : BackingRequired::No;
else {
// Need to fetch viewportConstrainedNotCompositedReason, but without doing all the work that needsToBeComposited does.
requiresCompositingForPosition(rendererForCompositingTests(layer), layer, queryData);
}
auto repaintTargetsSharedBacking = [&](RenderLayer& layer) {
return backingSharingState && layerRepaintTargetsBackingSharingLayer(layer, *backingSharingState);
};
auto repaintLayer = [&](RenderLayer& layer) {
if (repaintTargetsSharedBacking(layer)) {
LOG_WITH_STREAM(Compositing, stream << "Layer " << &layer << " needs to repaint into potential backing-sharing layer, postponing repaint");
backingSharingState->addLayerNeedingRepaint(layer);
} else
repaintOnCompositingChange(layer);
};
if (backingRequired == BackingRequired::Yes) {
// If we need to repaint, do so before making backing and disconnecting from the backing provider layer.
if (!layer.backing())
repaintLayer(layer);
layer.disconnectFromBackingProviderLayer();
enableCompositingMode();
if (!layer.backing()) {
layer.ensureBacking();
if (layer.isRenderViewLayer() && useCoordinatedScrollingForLayer(layer)) {
auto& frameView = m_renderView.frameView();
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->frameViewRootLayerDidChange(frameView);
#if HAVE(RUBBER_BANDING)
updateLayerForHeader(frameView.headerHeight());
updateLayerForFooter(frameView.footerHeight());
#endif
updateRootContentLayerClipping();
if (auto* tiledBacking = layer.backing()->tiledBacking())
tiledBacking->setTopContentInset(frameView.topContentInset());
}
// This layer and all of its descendants have cached repaints rects that are relative to
// the repaint container, so change when compositing changes; we need to update them here.
if (layer.parent())
layer.computeRepaintRectsIncludingDescendants();
layer.setNeedsCompositingGeometryUpdate();
layer.setNeedsCompositingConfigurationUpdate();
layer.setNeedsCompositingPaintOrderChildrenUpdate();
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()) {
auto* sourceLayer = downcast<RenderLayerModelObject>(*layer.renderer().parent()).layer();
if (auto* backing = sourceLayer->backing()) {
ASSERT(backing->graphicsLayer()->replicaLayer() == layer.backing()->graphicsLayer());
backing->graphicsLayer()->setReplicatedByLayer(nullptr);
}
}
layer.clearBacking();
layerChanged = true;
// This layer and all of its descendants have cached repaints rects that are relative to
// the repaint container, so change when compositing changes; we need to update them here,
// as long as shared backing isn't going to change our repaint container.
if (!repaintTargetsSharedBacking(layer))
layer.computeRepaintRectsIncludingDescendants();
// If we need to repaint, do so now that we've removed the backing.
repaintLayer(layer);
}
}
#if ENABLE(VIDEO)
if (layerChanged && is<RenderVideo>(layer.renderer())) {
// If it's a video, give the media player a chance to hook up to the layer.
downcast<RenderVideo>(layer.renderer()).acceleratedRenderingStateChanged();
}
#endif
if (layerChanged && is<RenderWidget>(layer.renderer())) {
auto* innerCompositor = frameContentsCompositor(downcast<RenderWidget>(layer.renderer()));
if (innerCompositor && innerCompositor->usesCompositing())
innerCompositor->updateRootLayerAttachment();
}
if (layerChanged)
layer.clearClipRectsIncludingDescendants(PaintingClipRects);
// If a fixed position layer gained/lost a backing or the reason not compositing it changed,
// the scrolling coordinator needs to recalculate whether it can do fast scrolling.
if (layer.renderer().isFixedPositioned()) {
if (layer.viewportConstrainedNotCompositedReason() != queryData.nonCompositedForPositionReason) {
layer.setViewportConstrainedNotCompositedReason(queryData.nonCompositedForPositionReason);
layerChanged = true;
}
if (layerChanged) {
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->frameViewFixedObjectsDidChange(m_renderView.frameView());
}
} else
layer.setViewportConstrainedNotCompositedReason(RenderLayer::NoNotCompositedReason);
if (layer.backing())
layer.backing()->updateDebugIndicators(m_showDebugBorders, m_showRepaintCounter);
return layerChanged;
}
bool RenderLayerCompositor::updateLayerCompositingState(RenderLayer& layer, const RenderLayer* compositingAncestor, RequiresCompositingData& queryData, BackingSharingState& backingSharingState)
{
bool layerChanged = updateBacking(layer, queryData, &backingSharingState);
// 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()->updateConfiguration(compositingAncestor))
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;
auto* repaintContainer = layer.renderer().containerForRepaint().renderer;
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();
}
}
// This method assumes that layout is up-to-date, unlike repaintOnCompositingChange().
void RenderLayerCompositor::repaintInCompositedAncestor(RenderLayer& layer, const LayoutRect& rect)
{
auto* compositedAncestor = layer.enclosingCompositingLayerForRepaint(ExcludeSelf).layer;
if (!compositedAncestor)
return;
ASSERT(compositedAncestor->backing());
LayoutRect repaintRect = rect;
repaintRect.move(layer.offsetFromAncestor(compositedAncestor));
compositedAncestor->setBackingNeedsRepaintInRect(repaintRect);
// 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.
if (compositedAncestor->isRenderViewLayer())
m_renderView.frameView().setNeedsOneShotDrawingSynchronization();
}
// FIXME: remove.
void RenderLayerCompositor::layerWasAdded(RenderLayer&, RenderLayer&)
{
}
void RenderLayerCompositor::layerWillBeRemoved(RenderLayer& parent, RenderLayer& child)
{
if (parent.renderer().renderTreeBeingDestroyed())
return;
if (child.isComposited())
repaintInCompositedAncestor(child, child.backing()->compositedBounds()); // FIXME: do via dirty bits?
else if (child.paintsIntoProvidedBacking()) {
auto* backingProviderLayer = child.backingProviderLayer();
// FIXME: Optimize this repaint.
backingProviderLayer->setBackingNeedsRepaint();
backingProviderLayer->backing()->removeBackingSharingLayer(child);
} else
return;
child.setNeedsCompositingLayerConnection();
}
RenderLayer* RenderLayerCompositor::enclosingNonStackingClippingLayer(const RenderLayer& layer) const
{
for (auto* parent = layer.parent(); parent; parent = parent->parent()) {
if (parent->isStackingContext())
return nullptr;
if (parent->renderer().hasClipOrNonVisibleOverflow())
return parent;
}
return nullptr;
}
void RenderLayerCompositor::computeExtent(const LayerOverlapMap& overlapMap, const RenderLayer& layer, OverlapExtent& extent) const
{
if (extent.extentComputed)
return;
LayoutRect layerBounds;
if (extent.hasTransformAnimation)
extent.animationCausesExtentUncertainty = !layer.getOverlapBoundsIncludingChildrenAccountingForTransformAnimations(layerBounds);
else
layerBounds = layer.overlapBounds();
// In the animating transform case, we avoid double-accounting for the transform because
// we told pushMappingsToAncestor() to ignore transforms earlier.
extent.bounds = enclosingLayoutRect(overlapMap.geometryMap().absoluteRect(layerBounds));
// Empty rects never intersect, but we need them to for the purposes of overlap testing.
if (extent.bounds.isEmpty())
extent.bounds.setSize(LayoutSize(1, 1));
RenderLayerModelObject& renderer = layer.renderer();
if (renderer.isFixedPositioned() && renderer.container() == &m_renderView) {
// Because fixed elements get moved around without re-computing overlap, we have to compute an overlap
// rect that covers all the locations that the fixed element could move to.
// FIXME: need to handle sticky too.
extent.bounds = m_renderView.frameView().fixedScrollableAreaBoundsInflatedForScrolling(extent.bounds);
}
extent.extentComputed = true;
}
enum class AncestorTraversal { Continue, Stop };
// This is a simplified version of containing block walking that only handles absolute position.
template <typename Function>
static AncestorTraversal traverseAncestorLayers(const RenderLayer& layer, Function&& function)
{
bool containingBlockCanSkipLayers = layer.renderer().isAbsolutelyPositioned();
RenderLayer* nextPaintOrderParent = layer.paintOrderParent();
for (const auto* ancestorLayer = layer.parent(); ancestorLayer; ancestorLayer = ancestorLayer->parent()) {
bool inContainingBlockChain = true;
if (containingBlockCanSkipLayers)
inContainingBlockChain = ancestorLayer->renderer().canContainAbsolutelyPositionedObjects();
if (function(*ancestorLayer, inContainingBlockChain, ancestorLayer == nextPaintOrderParent) == AncestorTraversal::Stop)
return AncestorTraversal::Stop;
if (inContainingBlockChain)
containingBlockCanSkipLayers = ancestorLayer->renderer().isAbsolutelyPositioned();
if (ancestorLayer == nextPaintOrderParent)
nextPaintOrderParent = ancestorLayer->paintOrderParent();
}
return AncestorTraversal::Continue;
}
static bool createsClippingScope(const RenderLayer& layer)
{
return layer.hasCompositedScrollableOverflow();
}
static Vector<LayerOverlapMap::LayerAndBounds> enclosingClippingScopes(const RenderLayer& layer, const RenderLayer& rootLayer)
{
Vector<LayerOverlapMap::LayerAndBounds> clippingScopes;
clippingScopes.append({ const_cast<RenderLayer&>(rootLayer), { } });
if (!layer.hasCompositedScrollingAncestor())
return clippingScopes;
traverseAncestorLayers(layer, [&](const RenderLayer& ancestorLayer, bool inContainingBlockChain, bool) {
if (inContainingBlockChain && createsClippingScope(ancestorLayer)) {
LayoutRect clipRect;
if (is<RenderBox>(ancestorLayer.renderer())) {
// FIXME: This is expensive. Broken with transforms.
LayoutPoint offsetFromRoot = ancestorLayer.convertToLayerCoords(&rootLayer, { });
clipRect = downcast<RenderBox>(ancestorLayer.renderer()).overflowClipRect(offsetFromRoot);
}
LayerOverlapMap::LayerAndBounds layerAndBounds { const_cast<RenderLayer&>(ancestorLayer), clipRect };
clippingScopes.insert(1, layerAndBounds); // Order is roots to leaves.
}
return AncestorTraversal::Continue;
});
return clippingScopes;
}
void RenderLayerCompositor::addToOverlapMap(LayerOverlapMap& overlapMap, const RenderLayer& layer, OverlapExtent& extent) const
{
if (layer.isRenderViewLayer())
return;
computeExtent(overlapMap, layer, extent);
// FIXME: constrain the scopes (by composited stacking context ancestor I think).
auto clippingScopes = enclosingClippingScopes(layer, rootRenderLayer());
LayoutRect clipRect;
if (layer.hasCompositedScrollingAncestor()) {
// Compute a clip up to the composited scrolling ancestor, then convert it to absolute coordinates.
auto& scrollingScope = clippingScopes.last();
auto& scopeLayer = scrollingScope.layer;
clipRect = layer.backgroundClipRect(RenderLayer::ClipRectsContext(&scopeLayer, TemporaryClipRects, IgnoreOverlayScrollbarSize, IgnoreOverflowClip)).rect();
if (!clipRect.isInfinite())
clipRect.setLocation(scopeLayer.convertToLayerCoords(&rootRenderLayer(), clipRect.location()));
} else
clipRect = layer.backgroundClipRect(RenderLayer::ClipRectsContext(&rootRenderLayer(), AbsoluteClipRects)).rect(); // FIXME: Incorrect for CSS regions.
auto clippedBounds = extent.bounds;
if (!clipRect.isInfinite()) {
// With delegated page scaling, pageScaleFactor() is not applied by RenderView, so we should not scale here.
if (!page().delegatesScaling())
clipRect.scale(pageScaleFactor());
clippedBounds.intersect(clipRect);
}
overlapMap.add(layer, clippedBounds, clippingScopes);
}
void RenderLayerCompositor::addDescendantsToOverlapMapRecursive(LayerOverlapMap& overlapMap, const RenderLayer& layer, const RenderLayer* ancestorLayer) const
{
if (!canBeComposited(layer))
return;
// A null ancestorLayer is an indication that 'layer' has already been pushed.
if (ancestorLayer) {
overlapMap.geometryMap().pushMappingsToAncestor(&layer, ancestorLayer);
OverlapExtent layerExtent;
addToOverlapMap(overlapMap, layer, layerExtent);
}
#if ASSERT_ENABLED
LayerListMutationDetector mutationChecker(const_cast<RenderLayer&>(layer));
#endif
for (auto* renderLayer : layer.negativeZOrderLayers())
addDescendantsToOverlapMapRecursive(overlapMap, *renderLayer, &layer);
for (auto* renderLayer : layer.normalFlowLayers())
addDescendantsToOverlapMapRecursive(overlapMap, *renderLayer, &layer);
for (auto* renderLayer : layer.positiveZOrderLayers())
addDescendantsToOverlapMapRecursive(overlapMap, *renderLayer, &layer);
if (ancestorLayer)
overlapMap.geometryMap().popMappingsToAncestor(ancestorLayer);
}
void RenderLayerCompositor::updateOverlapMap(LayerOverlapMap& overlapMap, const RenderLayer& layer, OverlapExtent& layerExtent, bool didPushContainer, bool addLayerToOverlap, bool addDescendantsToOverlap) const
{
if (addLayerToOverlap)
addToOverlapMap(overlapMap, layer, layerExtent);
if (addDescendantsToOverlap) {
// If this is the first non-root layer to composite, we need to add all the descendants we already traversed to the overlap map.
addDescendantsToOverlapMapRecursive(overlapMap, layer);
LOG_WITH_STREAM(CompositingOverlap, stream << "layer " << &layer << " composited post descendant traversal, added recursive " << overlapMap);
}
if (didPushContainer) {
overlapMap.popCompositingContainer(layer);
LOG_WITH_STREAM(CompositingOverlap, stream << "layer " << &layer << " is composited or shared, popped container " << overlapMap);
}
}
bool RenderLayerCompositor::layerOverlaps(const LayerOverlapMap& overlapMap, const RenderLayer& layer, OverlapExtent& layerExtent) const
{
computeExtent(overlapMap, layer, layerExtent);
auto clippingScopes = enclosingClippingScopes(layer, rootRenderLayer());
return overlapMap.overlapsLayers(layer, layerExtent.bounds, clippingScopes);
}
#if ENABLE(VIDEO)
bool RenderLayerCompositor::canAccelerateVideoRendering(RenderVideo& video) const
{
if (!m_hasAcceleratedCompositing)
return false;
return video.supportsAcceleratedRendering();
}
#endif
void RenderLayerCompositor::frameViewDidChangeLocation(const IntPoint& contentsOffset)
{
if (m_overflowControlsHostLayer)
m_overflowControlsHostLayer->setPosition(contentsOffset);
}
void RenderLayerCompositor::frameViewDidChangeSize()
{
if (auto* layer = m_renderView.layer())
layer->setNeedsCompositingGeometryUpdate();
if (m_scrolledContentsLayer) {
updateScrollLayerClipping();
frameViewDidScroll();
updateOverflowControlsLayers();
#if HAVE(RUBBER_BANDING)
if (m_layerForOverhangAreas) {
auto& frameView = m_renderView.frameView();
m_layerForOverhangAreas->setSize(frameView.frameRect().size());
m_layerForOverhangAreas->setPosition(FloatPoint(0, frameView.topContentInset()));
}
#endif
}
}
void RenderLayerCompositor::widgetDidChangeSize(RenderWidget& widget)
{
if (!widget.hasLayer())
return;
auto& layer = *widget.layer();
LOG_WITH_STREAM(Compositing, stream << "RenderLayerCompositor " << this << " widgetDidChangeSize (layer " << &layer << ")");
// Widget size affects answer to requiresCompositingForFrame() so we need to trigger
// a compositing update.
layer.setNeedsPostLayoutCompositingUpdate();
scheduleCompositingLayerUpdate();
if (layer.isComposited())
layer.backing()->updateAfterWidgetResize();
}
bool RenderLayerCompositor::hasCoordinatedScrolling() const
{
auto* scrollingCoordinator = this->scrollingCoordinator();
return scrollingCoordinator && scrollingCoordinator->coordinatesScrollingForFrameView(m_renderView.frameView());
}
void RenderLayerCompositor::updateScrollLayerPosition()
{
ASSERT(!hasCoordinatedScrolling());
ASSERT(m_scrolledContentsLayer);
auto& frameView = m_renderView.frameView();
IntPoint scrollPosition = frameView.scrollPosition();
// We use scroll position here because the root content layer is offset to account for scrollOrigin (see FrameView::positionForRootContentLayer).
m_scrolledContentsLayer->setPosition(FloatPoint(-scrollPosition.x(), -scrollPosition.y()));
if (auto* fixedBackgroundLayer = fixedRootBackgroundLayer())
fixedBackgroundLayer->setPosition(frameView.scrollPositionForFixedPosition());
}
void RenderLayerCompositor::updateScrollLayerClipping()
{
auto* layerForClipping = this->layerForClipping();
if (!layerForClipping)
return;
auto layerSize = m_renderView.frameView().sizeForVisibleContent();
layerForClipping->setSize(layerSize);
layerForClipping->setPosition(positionForClipLayer());
#if ENABLE(SCROLLING_THREAD)
if (layerForClipping == m_clipLayer) {
EventRegion eventRegion;
auto eventRegionContext = eventRegion.makeContext();
eventRegionContext.unite(IntRect({ }, layerSize), m_renderView, RenderStyle::defaultStyle());
#if ENABLE(INTERACTION_REGIONS_IN_EVENT_REGION)
eventRegionContext.copyInteractionRegionsToEventRegion();
#endif
m_clipLayer->setEventRegion(WTFMove(eventRegion));
}
#endif
}
FloatPoint RenderLayerCompositor::positionForClipLayer() const
{
auto& frameView = m_renderView.frameView();
return FloatPoint(
frameView.shouldPlaceVerticalScrollbarOnLeft() ? frameView.horizontalScrollbarIntrusion() : 0,
FrameView::yPositionForInsetClipLayer(frameView.scrollPosition(), frameView.topContentInset()));
}
void RenderLayerCompositor::frameViewDidScroll()
{
if (!m_scrolledContentsLayer)
return;
// If there's a scrolling coordinator that manages scrolling for this frame view,
// it will also manage updating the scroll layer position.
if (hasCoordinatedScrolling()) {
// We have to schedule a flush in order for the main TiledBacking to update its tile coverage.
scheduleRenderingUpdate();
return;
}
updateScrollLayerPosition();
}
void RenderLayerCompositor::frameViewDidAddOrRemoveScrollbars()
{
updateOverflowControlsLayers();
}
void RenderLayerCompositor::frameViewDidLayout()
{
if (auto* renderViewBacking = m_renderView.layer()->backing())
renderViewBacking->adjustTiledBackingCoverage();
}
void RenderLayerCompositor::rootLayerConfigurationChanged()
{
auto* renderViewBacking = m_renderView.layer()->backing();
if (renderViewBacking && renderViewBacking->isFrameLayerWithTiledBacking()) {
m_renderView.layer()->setNeedsCompositingConfigurationUpdate();
scheduleCompositingLayerUpdate();
}
}
void RenderLayerCompositor::updateCompositingForLayerTreeAsTextDump()
{
auto& frameView = m_renderView.frameView();
frameView.updateLayoutAndStyleIfNeededRecursive();
updateEventRegions();
for (auto* child = frameView.frame().tree().firstRenderedChild(); child; child = child->tree().traverseNextRendered()) {
if (auto* renderer = child->contentRenderer())
renderer->compositor().updateEventRegions();
}
updateCompositingLayers(CompositingUpdateType::AfterLayout);
if (!m_rootContentsLayer)
return;
flushPendingLayerChanges(true);
// We need to trigger an update because the flushPendingLayerChanges() will have pushed changes to platform layers,
// which may cause painting to happen in the current runloop.
page().triggerRenderingUpdateForTesting();
}
String RenderLayerCompositor::layerTreeAsText(OptionSet<LayerTreeAsTextOptions> options)
{
LOG_WITH_STREAM(Compositing, stream << "RenderLayerCompositor " << this << " layerTreeAsText");
updateCompositingForLayerTreeAsTextDump();
if (!m_rootContentsLayer)
return String();
// We skip dumping the scroll and clip layers to keep layerTreeAsText output
// similar between platforms.
String layerTreeText = m_rootContentsLayer->layerTreeAsText(options);
// Dump an empty layer tree only if the only composited layer is the main frame's tiled backing,
// so that tests expecting us to drop out of accelerated compositing when there are no layers succeed.
if (!hasContentCompositingLayers() && documentUsesTiledBacking() && !(options & LayerTreeAsTextOptions::IncludeTileCaches) && !(options & LayerTreeAsTextOptions::IncludeRootLayerProperties))
layerTreeText = emptyString();
// The true root layer is not included in the dump, so if we want to report
// its repaint rects, they must be included here.
if (options & LayerTreeAsTextOptions::IncludeRepaintRects)
return m_renderView.frameView().trackedRepaintRectsAsText() + layerTreeText;
return layerTreeText;
}
std::optional<String> RenderLayerCompositor::platformLayerTreeAsText(Element& element, OptionSet<PlatformLayerTreeAsTextFlags> flags)
{
LOG_WITH_STREAM(Compositing, stream << "RenderLayerCompositor " << this << " platformLayerTreeAsText");
updateCompositingForLayerTreeAsTextDump();
if (!element.renderer() || !element.renderer()->hasLayer())
return std::nullopt;
auto& layerModelObject = downcast<RenderLayerModelObject>(*element.renderer());
if (!layerModelObject.layer()->isComposited())
return std::nullopt;
auto* backing = layerModelObject.layer()->backing();
return backing->graphicsLayer()->platformLayerTreeAsText(flags);
}
static RenderView* frameContentsRenderView(RenderWidget& renderer)
{
if (auto* contentDocument = renderer.frameOwnerElement().contentDocument())
return contentDocument->renderView();
return nullptr;
}
RenderLayerCompositor* RenderLayerCompositor::frameContentsCompositor(RenderWidget& renderer)
{
if (auto* view = frameContentsRenderView(renderer))
return &view->compositor();
return nullptr;
}
bool RenderLayerCompositor::parentFrameContentLayers(RenderWidget& renderer)
{
auto* innerCompositor = frameContentsCompositor(renderer);
if (!innerCompositor || !innerCompositor->usesCompositing() || innerCompositor->rootLayerAttachment() != RootLayerAttachedViaEnclosingFrame)
return false;
auto* layer = renderer.layer();
if (!layer->isComposited())
return false;
auto* backing = layer->backing();
auto* hostingLayer = backing->parentForSublayers();
auto* rootLayer = innerCompositor->rootGraphicsLayer();
if (hostingLayer->children().size() != 1 || hostingLayer->children()[0].ptr() != rootLayer) {
hostingLayer->removeAllChildren();
hostingLayer->addChild(*rootLayer);
}
if (auto frameHostingNodeID = backing->scrollingNodeIDForRole(ScrollCoordinationRole::FrameHosting)) {
auto* contentsRenderView = frameContentsRenderView(renderer);
if (auto frameRootScrollingNodeID = contentsRenderView->frameView().scrollingNodeID()) {
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->insertNode(ScrollingNodeType::Subframe, frameRootScrollingNodeID, frameHostingNodeID, 0);
}
}
// FIXME: Why always return true and not just when the layers changed?
return true;
}
void RenderLayerCompositor::repaintCompositedLayers()
{
recursiveRepaintLayer(rootRenderLayer());
}
void RenderLayerCompositor::recursiveRepaintLayer(RenderLayer& layer)
{
layer.updateLayerListsIfNeeded();
// FIXME: This method does not work correctly with transforms.
if (layer.isComposited() && !layer.backing()->paintsIntoCompositedAncestor())
layer.setBackingNeedsRepaint();
#if ASSERT_ENABLED
LayerListMutationDetector mutationChecker(layer);
#endif
if (layer.hasCompositingDescendant()) {
for (auto* renderLayer : layer.negativeZOrderLayers())
recursiveRepaintLayer(*renderLayer);
for (auto* renderLayer : layer.positiveZOrderLayers())
recursiveRepaintLayer(*renderLayer);
}
for (auto* renderLayer : layer.normalFlowLayers())
recursiveRepaintLayer(*renderLayer);
}
bool RenderLayerCompositor::layerRepaintTargetsBackingSharingLayer(RenderLayer& layer, BackingSharingState& sharingState) const
{
if (!sharingState.backingProviderCandidate())
return false;
for (const RenderLayer* currLayer = &layer; currLayer; currLayer = currLayer->paintOrderParent()) {
if (compositedWithOwnBackingStore(*currLayer))
return false;
if (currLayer->paintsIntoProvidedBacking())
return false;
if (sharingState.isPotentialBackingSharingLayer(*currLayer))
return true;
}
return false;
}
RenderLayer& RenderLayerCompositor::rootRenderLayer() const
{
return *m_renderView.layer();
}
GraphicsLayer* RenderLayerCompositor::rootGraphicsLayer() const
{
if (m_overflowControlsHostLayer)
return m_overflowControlsHostLayer.get();
return m_rootContentsLayer.get();
}
void RenderLayerCompositor::setIsInWindow(bool isInWindow)
{
LOG(Compositing, "RenderLayerCompositor %p setIsInWindow %d", this, isInWindow);
if (!usesCompositing())
return;
if (auto* rootLayer = rootGraphicsLayer()) {
GraphicsLayer::traverse(*rootLayer, [isInWindow](GraphicsLayer& layer) {
layer.setIsInWindow(isInWindow);
});
}
if (isInWindow) {
if (m_rootLayerAttachment != RootLayerUnattached)
return;
RootLayerAttachment attachment = isMainFrameCompositor() ? RootLayerAttachedViaChromeClient : RootLayerAttachedViaEnclosingFrame;
attachRootLayer(attachment);
#if PLATFORM(IOS_FAMILY)
if (m_legacyScrollingLayerCoordinator) {
m_legacyScrollingLayerCoordinator->registerAllViewportConstrainedLayers(*this);
m_legacyScrollingLayerCoordinator->registerAllScrollingLayers();
}
#endif
} else {
if (m_rootLayerAttachment == RootLayerUnattached)
return;
detachRootLayer();
#if PLATFORM(IOS_FAMILY)
if (m_legacyScrollingLayerCoordinator) {
m_legacyScrollingLayerCoordinator->unregisterAllViewportConstrainedLayers();
m_legacyScrollingLayerCoordinator->unregisterAllScrollingLayers();
}
#endif
}
}
void RenderLayerCompositor::invalidateEventRegionForAllFrames()
{
for (auto* frame = &page().mainFrame(); frame; frame = frame->tree().traverseNext()) {
if (auto* view = frame->contentRenderer())
view->compositor().invalidateEventRegionForAllLayers();
}
}
void RenderLayerCompositor::invalidateEventRegionForAllLayers()
{
applyToCompositedLayerIncludingDescendants(*m_renderView.layer(), [](auto& layer) {
layer.invalidateEventRegion(RenderLayer::EventRegionInvalidationReason::SettingDidChange);
});
}
void RenderLayerCompositor::clearBackingForAllLayers()
{
applyToCompositedLayerIncludingDescendants(*m_renderView.layer(), [](auto& layer) { layer.clearBacking(); });
}
void RenderLayerCompositor::updateRootLayerPosition()
{
if (m_rootContentsLayer) {
m_rootContentsLayer->setSize(m_renderView.frameView().contentsSize());
m_rootContentsLayer->setPosition(m_renderView.frameView().positionForRootContentLayer());
m_rootContentsLayer->setAnchorPoint(FloatPoint3D());
}
updateScrollLayerClipping();
#if HAVE(RUBBER_BANDING)
if (m_contentShadowLayer && m_rootContentsLayer) {
m_contentShadowLayer->setPosition(m_rootContentsLayer->position());
m_contentShadowLayer->setSize(m_rootContentsLayer->size());
}
updateLayerForTopOverhangArea(m_layerForTopOverhangArea != nullptr);
updateLayerForBottomOverhangArea(m_layerForBottomOverhangArea != nullptr);
updateLayerForHeader(m_layerForHeader != nullptr);
updateLayerForFooter(m_layerForFooter != nullptr);
#endif
}
bool RenderLayerCompositor::has3DContent() const
{
return layerHas3DContent(rootRenderLayer());
}
bool RenderLayerCompositor::needsToBeComposited(const RenderLayer& layer, RequiresCompositingData& queryData) const
{
if (!canBeComposited(layer))
return false;
return requiresCompositingLayer(layer, queryData) || layer.mustCompositeForIndirectReasons() || (usesCompositing() && layer.isRenderViewLayer());
}
// 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.
// FIXME: is clipsCompositingDescendants() an intrinsic reason?
bool RenderLayerCompositor::requiresCompositingLayer(const RenderLayer& layer, RequiresCompositingData& queryData) const
{
auto& renderer = rendererForCompositingTests(layer);
if (!renderer.layer()) {
ASSERT_NOT_REACHED();
return false;
}
// The root layer always has a compositing layer, but it may not have backing.
return requiresCompositingForTransform(renderer)
|| requiresCompositingForAnimation(renderer)
|| requiresCompositingForPosition(renderer, *renderer.layer(), queryData)
|| requiresCompositingForCanvas(renderer)
|| requiresCompositingForFilters(renderer)
|| requiresCompositingForWillChange(renderer)
|| requiresCompositingForBackfaceVisibility(renderer)
|| requiresCompositingForVideo(renderer)
|| requiresCompositingForModel(renderer)
|| requiresCompositingForFrame(renderer, queryData)
|| requiresCompositingForPlugin(renderer, queryData)
|| requiresCompositingForOverflowScrolling(*renderer.layer(), queryData);
}
bool RenderLayerCompositor::canBeComposited(const RenderLayer& layer) const
{
if (m_hasAcceleratedCompositing && layer.isSelfPaintingLayer()) {
if (!layer.isInsideFragmentedFlow())
return true;
// CSS Regions flow threads do not need to be composited as we use composited RenderFragmentContainers
// to render the background of the RenderFragmentedFlow.
if (layer.isRenderFragmentedFlow())
return false;
return true;
}
return false;
}
#if ENABLE(FULLSCREEN_API)
enum class FullScreenDescendant { Yes, No, NotApplicable };
static FullScreenDescendant isDescendantOfFullScreenLayer(const RenderLayer& layer)
{
auto& document = layer.renderer().document();
if (!document.fullscreenManager().isFullscreen() || !document.fullscreenManager().fullscreenRenderer())
return FullScreenDescendant::NotApplicable;
auto* fullScreenLayer = document.fullscreenManager().fullscreenRenderer()->layer();
if (!fullScreenLayer) {
ASSERT_NOT_REACHED();
return FullScreenDescendant::NotApplicable;
}
return layer.isDescendantOf(*fullScreenLayer) ? FullScreenDescendant::Yes : FullScreenDescendant::No;
}
#endif
bool RenderLayerCompositor::requiresOwnBackingStore(const RenderLayer& layer, const RenderLayer* compositingAncestorLayer, const LayoutRect& layerCompositedBoundsInAncestor, const LayoutRect& ancestorCompositedBounds) const
{
auto& renderer = layer.renderer();
if (compositingAncestorLayer
&& !(compositingAncestorLayer->backing()->graphicsLayer()->drawsContent()
|| compositingAncestorLayer->backing()->paintsIntoWindow()
|| compositingAncestorLayer->backing()->paintsIntoCompositedAncestor()))
return true;
RequiresCompositingData queryData;
if (layer.isRenderViewLayer()
|| layer.transform() // note: excludes perspective and transformStyle3D.
|| requiresCompositingForAnimation(renderer)
|| requiresCompositingForPosition(renderer, layer, queryData)
|| requiresCompositingForCanvas(renderer)
|| requiresCompositingForFilters(renderer)
|| requiresCompositingForWillChange(renderer)
|| requiresCompositingForBackfaceVisibility(renderer)
|| requiresCompositingForVideo(renderer)
|| requiresCompositingForModel(renderer)
|| requiresCompositingForFrame(renderer, queryData)
|| requiresCompositingForPlugin(renderer, queryData)
|| requiresCompositingForOverflowScrolling(layer, queryData)
|| needsContentsCompositingLayer(layer)
|| renderer.isTransparent()
|| renderer.hasMask()
|| renderer.hasReflection()
|| renderer.hasFilter()
|| renderer.hasBackdropFilter())
return true;
if (layer.isComposited() && layer.backing()->hasBackingSharingLayers())
return true;
// FIXME: We really need to keep track of the ancestor layer that has its own backing store.
if (!ancestorCompositedBounds.contains(layerCompositedBoundsInAncestor))
return true;
if (layer.mustCompositeForIndirectReasons()) {
IndirectCompositingReason reason = layer.indirectCompositingReason();
return reason == IndirectCompositingReason::Overlap
|| reason == IndirectCompositingReason::OverflowScrollPositioning
|| reason == IndirectCompositingReason::Stacking
|| reason == IndirectCompositingReason::BackgroundLayer
|| reason == IndirectCompositingReason::GraphicalEffect
|| reason == IndirectCompositingReason::Preserve3D; // preserve-3d has to create backing store to ensure that 3d-transformed elements intersect.
}
return false;
}
OptionSet<CompositingReason> RenderLayerCompositor::reasonsForCompositing(const RenderLayer& layer) const
{
OptionSet<CompositingReason> reasons;
if (!layer.isComposited())
return reasons;
RequiresCompositingData queryData;
auto& renderer = rendererForCompositingTests(layer);
if (requiresCompositingForTransform(renderer))
reasons.add(CompositingReason::Transform3D);
if (requiresCompositingForVideo(renderer))
reasons.add(CompositingReason::Video);
else if (requiresCompositingForCanvas(renderer))
reasons.add(CompositingReason::Canvas);
else if (requiresCompositingForModel(renderer))
reasons.add(CompositingReason::Model);
else if (requiresCompositingForPlugin(renderer, queryData))
reasons.add(CompositingReason::Plugin);
else if (requiresCompositingForFrame(renderer, queryData))
reasons.add(CompositingReason::IFrame);
if ((canRender3DTransforms() && renderer.style().backfaceVisibility() == BackfaceVisibility::Hidden))
reasons.add(CompositingReason::BackfaceVisibilityHidden);
if (requiresCompositingForAnimation(renderer))
reasons.add(CompositingReason::Animation);
if (requiresCompositingForFilters(renderer))
reasons.add(CompositingReason::Filters);
if (requiresCompositingForWillChange(renderer))
reasons.add(CompositingReason::WillChange);
if (requiresCompositingForPosition(renderer, *renderer.layer(), queryData))
reasons.add(renderer.isFixedPositioned() ? CompositingReason::PositionFixed : CompositingReason::PositionSticky);
if (requiresCompositingForOverflowScrolling(*renderer.layer(), queryData))
reasons.add(CompositingReason::OverflowScrolling);
switch (renderer.layer()->indirectCompositingReason()) {
case IndirectCompositingReason::None:
break;
case IndirectCompositingReason::Clipping:
reasons.add(CompositingReason::ClipsCompositingDescendants);
break;
case IndirectCompositingReason::Stacking:
reasons.add(CompositingReason::Stacking);
break;
case IndirectCompositingReason::OverflowScrollPositioning:
reasons.add(CompositingReason::OverflowScrollPositioning);
break;
case IndirectCompositingReason::Overlap:
reasons.add(CompositingReason::Overlap);
break;
case IndirectCompositingReason::BackgroundLayer:
reasons.add(CompositingReason::NegativeZIndexChildren);
break;
case IndirectCompositingReason::GraphicalEffect:
if (renderer.hasTransform())
reasons.add(CompositingReason::TransformWithCompositedDescendants);
if (renderer.isTransparent())
reasons.add(CompositingReason::OpacityWithCompositedDescendants);
if (renderer.hasMask())
reasons.add(CompositingReason::MaskWithCompositedDescendants);
if (renderer.hasReflection())
reasons.add(CompositingReason::ReflectionWithCompositedDescendants);
if (renderer.hasFilter() || renderer.hasBackdropFilter())
reasons.add(CompositingReason::FilterWithCompositedDescendants);
#if ENABLE(CSS_COMPOSITING)
if (layer.isolatesCompositedBlending())
reasons.add(CompositingReason::IsolatesCompositedBlendingDescendants);
if (layer.hasBlendMode())
reasons.add(CompositingReason::BlendingWithCompositedDescendants);
#endif
break;
case IndirectCompositingReason::Perspective:
reasons.add(CompositingReason::Perspective);
break;
case IndirectCompositingReason::Preserve3D:
reasons.add(CompositingReason::Preserve3D);
break;
}
if (usesCompositing() && renderer.layer()->isRenderViewLayer())
reasons.add(CompositingReason::Root);
return reasons;
}
static const char* compositingReasonToString(CompositingReason reason)
{
switch (reason) {
case CompositingReason::Transform3D: return "3D transform";
case CompositingReason::Video: return "video";
case CompositingReason::Canvas: return "canvas";
case CompositingReason::Plugin: return "plugin";
case CompositingReason::IFrame: return "iframe";
case CompositingReason::BackfaceVisibilityHidden: return "backface-visibility: hidden";
case CompositingReason::ClipsCompositingDescendants: return "clips compositing descendants";
case CompositingReason::Animation: return "animation";
case CompositingReason::Filters: return "filters";
case CompositingReason::PositionFixed: return "position: fixed";
case CompositingReason::PositionSticky: return "position: sticky";
case CompositingReason::OverflowScrolling: return "async overflow scrolling";
case CompositingReason::Stacking: return "stacking";
case CompositingReason::Overlap: return "overlap";
case CompositingReason::OverflowScrollPositioning: return "overflow scroll positioning";
case CompositingReason::NegativeZIndexChildren: return "negative z-index children";
case CompositingReason::TransformWithCompositedDescendants: return "transform with composited descendants";
case CompositingReason::OpacityWithCompositedDescendants: return "opacity with composited descendants";
case CompositingReason::MaskWithCompositedDescendants: return "mask with composited descendants";
case CompositingReason::ReflectionWithCompositedDescendants: return "reflection with composited descendants";
case CompositingReason::FilterWithCompositedDescendants: return "filter with composited descendants";
case CompositingReason::BlendingWithCompositedDescendants: return "blending with composited descendants";
case CompositingReason::IsolatesCompositedBlendingDescendants: return "isolates composited blending descendants";
case CompositingReason::Perspective: return "perspective";
case CompositingReason::Preserve3D: return "preserve-3d";
case CompositingReason::WillChange: return "will-change";
case CompositingReason::Root: return "root";
case CompositingReason::Model: return "model";
}
return "";
}
#if !LOG_DISABLED
const char* RenderLayerCompositor::logOneReasonForCompositing(const RenderLayer& layer)
{
for (auto reason : reasonsForCompositing(layer))
return compositingReasonToString(reason);
return "";
}
#endif
static bool canUseDescendantClippingLayer(const RenderLayer& layer)
{
if (layer.isolatesCompositedBlending())
return false;
// We can only use the "descendant clipping layer" strategy when the clip rect is entirely within
// the border box, because of interactions with border-radius clipping and compositing.
if (auto* renderer = layer.renderBox(); renderer && renderer->hasClip()) {
auto borderBoxRect = renderer->borderBoxRect();
auto clipRect = renderer->clipRect({ }, nullptr);
bool clipRectInsideBorderRect = intersection(borderBoxRect, clipRect) == clipRect;
return clipRectInsideBorderRect;
}
return true;
}
// 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.
// FIXME: can we do this without a tree walk?
bool RenderLayerCompositor::clippedByAncestor(RenderLayer& layer, const RenderLayer* compositingAncestor) const
{
ASSERT(layer.isComposited());
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. The exception is when the compositingAncestor isolates composited blending children,
// in this case it is not allowed to clipsCompositingDescendants() and each of its children
// will be clippedByAncestor()s, including the compositingAncestor.
auto* computeClipRoot = compositingAncestor;
if (canUseDescendantClippingLayer(*compositingAncestor)) {
computeClipRoot = nullptr;
auto* parent = &layer;
while (parent) {
auto* next = parent->parent();
if (next == compositingAncestor) {
computeClipRoot = parent;
break;
}
parent = next;
}
if (!computeClipRoot || computeClipRoot == &layer)
return false;
}
auto backgroundClipRect = layer.backgroundClipRect(RenderLayer::ClipRectsContext(computeClipRoot, TemporaryClipRects));
return !backgroundClipRect.isInfinite(); // FIXME: Incorrect for CSS regions.
}
bool RenderLayerCompositor::updateAncestorClippingStack(const RenderLayer& layer, const RenderLayer* compositingAncestor) const
{
ASSERT(layer.isComposited());
auto clippingStack = computeAncestorClippingStack(layer, compositingAncestor);
return layer.backing()->updateAncestorClippingStack(WTFMove(clippingStack));
}
Vector<CompositedClipData> RenderLayerCompositor::computeAncestorClippingStack(const RenderLayer& layer, const RenderLayer* compositingAncestor) const
{
// On first pass in WK1, the root may not have become composited yet.
if (!compositingAncestor)
return { };
// We'll start by building a child-to-ancestors stack.
Vector<CompositedClipData> newStack;
// Walk up the containing block chain to composited ancestor, prepending an entry to the clip stack for:
// * each composited scrolling layer
// * each set of RenderLayers which contribute a clip.
bool haveNonScrollableClippingIntermediateLayer = false;
const RenderLayer* currentClippedLayer = &layer;
auto pushNonScrollableClip = [&](const RenderLayer& clippedLayer, const RenderLayer& clippingRoot, ShouldRespectOverflowClip respectClip = IgnoreOverflowClip) {
// Pass IgnoreOverflowClip to ignore overflow contributed by clippingRoot (which may be a scroller).
auto clipRect = clippedLayer.backgroundClipRect(RenderLayer::ClipRectsContext(&clippingRoot, TemporaryClipRects, IgnoreOverlayScrollbarSize, respectClip)).rect();
auto offset = layer.convertToLayerCoords(&clippingRoot, { }, RenderLayer::AdjustForColumns);
clipRect.moveBy(-offset);
CompositedClipData clipData { const_cast<RenderLayer*>(&clippedLayer), clipRect, false };
newStack.insert(0, WTFMove(clipData));
};
traverseAncestorLayers(layer, [&](const RenderLayer& ancestorLayer, bool isContainingBlockChain, bool /*isPaintOrderAncestor*/) {
if (&ancestorLayer == compositingAncestor) {
if (haveNonScrollableClippingIntermediateLayer)
pushNonScrollableClip(*currentClippedLayer, ancestorLayer, !canUseDescendantClippingLayer(ancestorLayer) ? RespectOverflowClip : IgnoreOverflowClip);
else if (!canUseDescendantClippingLayer(ancestorLayer) && newStack.isEmpty())
pushNonScrollableClip(*currentClippedLayer, ancestorLayer, RespectOverflowClip);
return AncestorTraversal::Stop;
}
if (isContainingBlockChain && ancestorLayer.renderer().hasClipOrNonVisibleOverflow()) {
if (ancestorLayer.hasCompositedScrollableOverflow()) {
if (haveNonScrollableClippingIntermediateLayer) {
pushNonScrollableClip(*currentClippedLayer, ancestorLayer);
haveNonScrollableClippingIntermediateLayer = false;
}
auto clipRect = parentRelativeScrollableRect(ancestorLayer, &ancestorLayer);
auto offset = layer.convertToLayerCoords(&ancestorLayer, { }, RenderLayer::AdjustForColumns);
clipRect.moveBy(-offset);
CompositedClipData clipData { const_cast<RenderLayer*>(&ancestorLayer), clipRect, true };
newStack.insert(0, WTFMove(clipData));
currentClippedLayer = &ancestorLayer;
} else
haveNonScrollableClippingIntermediateLayer = true;
}
return AncestorTraversal::Continue;
});
return newStack;
}
// Note that this returns the ScrollingNodeID of the scroller this layer is embedded in, not the layer's own ScrollingNodeID if it has one.
ScrollingNodeID RenderLayerCompositor::asyncScrollableContainerNodeID(const RenderObject& renderer)
{
auto* enclosingLayer = renderer.enclosingLayer();
if (!enclosingLayer)
return 0;
auto layerScrollingNodeID = [](const RenderLayer& layer) -> ScrollingNodeID {
if (layer.isComposited())
return layer.backing()->scrollingNodeIDForRole(ScrollCoordinationRole::Scrolling);
return 0;
};
// If the renderer is inside the layer, we care about the layer's scrollability. Otherwise, we let traverseAncestorLayers look at ancestors.
if (!renderer.hasLayer()) {
if (auto scrollingNodeID = layerScrollingNodeID(*enclosingLayer))
return scrollingNodeID;
}
ScrollingNodeID containerScrollingNodeID = 0;
traverseAncestorLayers(*enclosingLayer, [&](const RenderLayer& ancestorLayer, bool isContainingBlockChain, bool /*isPaintOrderAncestor*/) {
if (isContainingBlockChain && ancestorLayer.hasCompositedScrollableOverflow()) {
containerScrollingNodeID = layerScrollingNodeID(ancestorLayer);
return AncestorTraversal::Stop;
}
return AncestorTraversal::Continue;
});
return containerScrollingNodeID;
}
bool RenderLayerCompositor::isCompositedSubframeRenderer(const RenderObject& renderer)
{
if (!is<RenderWidget>(renderer))
return false;
return downcast<RenderWidget>(renderer).requiresAcceleratedCompositing();
}
// 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)
{
if (!(layer.hasCompositingDescendant() && layer.renderer().hasClipOrNonVisibleOverflow()))
return false;
if (layer.hasCompositedNonContainedDescendants())
return false;
return canUseDescendantClippingLayer(layer);
}
bool RenderLayerCompositor::requiresCompositingForAnimation(RenderLayerModelObject& renderer) const
{
if (!(m_compositingTriggers & ChromeClient::AnimationTrigger))
return false;
if (auto styleable = Styleable::fromRenderer(renderer)) {
if (auto* effectsStack = styleable->keyframeEffectStack()) {
return (effectsStack->isCurrentlyAffectingProperty(CSSPropertyOpacity)
&& (usesCompositing() || (m_compositingTriggers & ChromeClient::AnimatedOpacityTrigger)))
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyFilter)
#if ENABLE(FILTERS_LEVEL_2)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyWebkitBackdropFilter)
#endif
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyTranslate)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyScale)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyRotate)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyTransform)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyOffsetAnchor)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyOffsetDistance)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyOffsetPath)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyOffsetPosition)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyOffsetRotate);
}
}
return false;
}
static bool styleHas3DTransformOperation(const RenderStyle& style)
{
return style.transform().has3DOperation()
|| (style.translate() && style.translate()->is3DOperation())
|| (style.scale() && style.scale()->is3DOperation())
|| (style.rotate() && style.rotate()->is3DOperation());
}
static bool styleTransformOperationsAreRepresentableIn2D(const RenderStyle& style)
{
return style.transform().isRepresentableIn2D()
&& (!style.translate() || style.translate()->isRepresentableIn2D())
&& (!style.scale() || style.scale()->isRepresentableIn2D())
&& (!style.rotate() || style.rotate()->isRepresentableIn2D());
}
bool RenderLayerCompositor::requiresCompositingForTransform(RenderLayerModelObject& renderer) const
{
if (!(m_compositingTriggers & ChromeClient::ThreeDTransformTrigger))
return false;
// 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.
if (!renderer.hasTransform())
return false;
switch (m_compositingPolicy) {
case CompositingPolicy::Normal:
return styleHas3DTransformOperation(renderer.style());
case CompositingPolicy::Conservative:
// Continue to allow pages to avoid the very slow software filter path.
if (styleHas3DTransformOperation(renderer.style()) && renderer.hasFilter())
return true;
return styleTransformOperationsAreRepresentableIn2D(renderer.style()) ? false : true;
}
return false;
}
bool RenderLayerCompositor::requiresCompositingForBackfaceVisibility(RenderLayerModelObject& renderer) const
{
if (!(m_compositingTriggers & ChromeClient::ThreeDTransformTrigger))
return false;
if (renderer.style().backfaceVisibility() != BackfaceVisibility::Hidden)
return false;
if (renderer.layer()->has3DTransformedAncestor())
return true;
// FIXME: workaround for webkit.org/b/132801
auto* stackingContext = renderer.layer()->stackingContext();
if (stackingContext && stackingContext->renderer().style().preserves3D())
return true;
return false;
}
bool RenderLayerCompositor::requiresCompositingForVideo(RenderLayerModelObject& renderer) const
{
if (!(m_compositingTriggers & ChromeClient::VideoTrigger))
return false;
#if ENABLE(VIDEO)
if (!is<RenderVideo>(renderer))
return false;
auto& video = downcast<RenderVideo>(renderer);
if ((video.requiresImmediateCompositing() || video.shouldDisplayVideo()) && canAccelerateVideoRendering(video))
return true;
#else
UNUSED_PARAM(renderer);
#endif
return false;
}
bool RenderLayerCompositor::requiresCompositingForCanvas(RenderLayerModelObject& renderer) const
{
if (!(m_compositingTriggers & ChromeClient::CanvasTrigger))
return false;
if (!renderer.isCanvas())
return false;
bool isCanvasLargeEnoughToForceCompositing = true;
#if !USE(COMPOSITING_FOR_SMALL_CANVASES)
auto* canvas = downcast<HTMLCanvasElement>(renderer.element());
auto canvasArea = canvas->size().area<RecordOverflow>();
isCanvasLargeEnoughToForceCompositing = !canvasArea.hasOverflowed() && canvasArea >= canvasAreaThresholdRequiringCompositing;
#endif
CanvasCompositingStrategy compositingStrategy = canvasCompositingStrategy(renderer);
if (compositingStrategy == CanvasAsLayerContents)
return true;
if (m_compositingPolicy == CompositingPolicy::Normal)
return compositingStrategy == CanvasPaintedToLayer && isCanvasLargeEnoughToForceCompositing;
return false;
}
bool RenderLayerCompositor::requiresCompositingForFilters(RenderLayerModelObject& renderer) const
{
#if ENABLE(FILTERS_LEVEL_2)
if (renderer.hasBackdropFilter())
return true;
#endif
if (!(m_compositingTriggers & ChromeClient::FilterTrigger))
return false;
return renderer.hasFilter();
}
bool RenderLayerCompositor::requiresCompositingForWillChange(RenderLayerModelObject& renderer) const
{
if (!renderer.style().willChange() || !renderer.style().willChange()->canTriggerCompositing())
return false;
#if ENABLE(FULLSCREEN_API)
// FIXME: does this require layout?
if (renderer.layer() && isDescendantOfFullScreenLayer(*renderer.layer()) == FullScreenDescendant::No)
return false;
#endif
#if !PLATFORM(MAC)
// Ugly workaround for rdar://71881767. Undo when webkit.org/b/222092 and webkit.org/b/222132 are fixed.
if (m_compositingPolicy == CompositingPolicy::Conservative)
return false;
#endif
if (is<RenderBox>(renderer))
return true;
return renderer.style().willChange()->canTriggerCompositingOnInline();
}
bool RenderLayerCompositor::requiresCompositingForModel(RenderLayerModelObject& renderer) const
{
#if ENABLE(MODEL_ELEMENT)
if (is<RenderModel>(renderer))
return true;
#else
UNUSED_PARAM(renderer);
#endif
return false;
}
bool RenderLayerCompositor::requiresCompositingForPlugin(RenderLayerModelObject& renderer, RequiresCompositingData& queryData) const
{
if (!(m_compositingTriggers & ChromeClient::PluginTrigger))
return false;
bool isCompositedPlugin = is<RenderEmbeddedObject>(renderer) && downcast<RenderEmbeddedObject>(renderer).allowsAcceleratedCompositing();
if (!isCompositedPlugin)
return false;
auto& pluginRenderer = downcast<RenderWidget>(renderer);
if (pluginRenderer.style().visibility() != Visibility::Visible)
return false;
// If we can't reliably know the size of the plugin yet, don't change compositing state.
if (queryData.layoutUpToDate == LayoutUpToDate::No) {
queryData.reevaluateAfterLayout = true;
return pluginRenderer.isComposited();
}
// Don't go into compositing mode if height or width are zero, or size is 1x1.
IntRect contentBox = snappedIntRect(pluginRenderer.contentBoxRect());
return (contentBox.height() * contentBox.width() > 1);
}
bool RenderLayerCompositor::requiresCompositingForFrame(RenderLayerModelObject& renderer, RequiresCompositingData& queryData) const
{
if (!is<RenderWidget>(renderer))
return false;
auto& frameRenderer = downcast<RenderWidget>(renderer);
if (frameRenderer.style().visibility() != Visibility::Visible)
return false;
if (!frameRenderer.requiresAcceleratedCompositing())
return false;
if (queryData.layoutUpToDate == LayoutUpToDate::No) {
queryData.reevaluateAfterLayout = true;
return frameRenderer.isComposited();
}
// Don't go into compositing mode if height or width are zero.
return !snappedIntRect(frameRenderer.contentBoxRect()).isEmpty();
}
bool RenderLayerCompositor::requiresCompositingForScrollableFrame(RequiresCompositingData& queryData) const
{
if (isMainFrameCompositor())
return false;
#if PLATFORM(COCOA) || USE(NICOSIA)
if (!m_renderView.settings().asyncFrameScrollingEnabled())
return false;
#endif
if (!(m_compositingTriggers & ChromeClient::ScrollableNonMainFrameTrigger))
return false;
if (queryData.layoutUpToDate == LayoutUpToDate::No) {
queryData.reevaluateAfterLayout = true;
return m_renderView.isComposited();
}
return m_renderView.frameView().isScrollable();
}
bool RenderLayerCompositor::requiresCompositingForPosition(RenderLayerModelObject& renderer, const RenderLayer& layer, RequiresCompositingData& queryData) const
{
// position:fixed elements that create their own stacking context (e.g. have an explicit z-index,
// opacity, transform) can get their own composited layer. A stacking context is required otherwise
// z-index and clipping will be broken.
if (!renderer.isPositioned())
return false;
#if ENABLE(FULLSCREEN_API)
if (isDescendantOfFullScreenLayer(layer) == FullScreenDescendant::No)
return false;
#endif
auto position = renderer.style().position();
bool isFixed = renderer.isFixedPositioned();
if (isFixed && !layer.isStackingContext())
return false;
bool isSticky = renderer.isInFlowPositioned() && position == PositionType::Sticky;
if (!isFixed && !isSticky)
return false;
// FIXME: acceleratedCompositingForFixedPositionEnabled should probably be renamed acceleratedCompositingForViewportConstrainedPositionEnabled().
if (!m_renderView.settings().acceleratedCompositingForFixedPositionEnabled())
return false;
if (isSticky)
return isAsyncScrollableStickyLayer(layer);
if (queryData.layoutUpToDate == LayoutUpToDate::No) {
queryData.reevaluateAfterLayout = true;
return layer.isComposited();
}
auto container = renderer.container();
ASSERT(container);
// Don't promote fixed position elements that are descendants of a non-view container, e.g. transformed elements.
// They will stay fixed wrt the container rather than the enclosing frame.
if (container != &m_renderView) {
queryData.nonCompositedForPositionReason = RenderLayer::NotCompositedForNonViewContainer;
return false;
}
bool paintsContent = layer.isVisuallyNonEmpty() || layer.hasVisibleDescendant();
if (!paintsContent) {
queryData.nonCompositedForPositionReason = RenderLayer::NotCompositedForNoVisibleContent;
return false;
}
bool intersectsViewport = fixedLayerIntersectsViewport(layer);
if (!intersectsViewport) {
queryData.nonCompositedForPositionReason = RenderLayer::NotCompositedForBoundsOutOfView;
LOG_WITH_STREAM(Compositing, stream << "Layer " << &layer << " is outside the viewport");
return false;
}
return true;
}
bool RenderLayerCompositor::requiresCompositingForOverflowScrolling(const RenderLayer& layer, RequiresCompositingData& queryData) const
{
if (!layer.canUseCompositedScrolling())
return false;
if (queryData.layoutUpToDate == LayoutUpToDate::No) {
queryData.reevaluateAfterLayout = true;
return layer.isComposited();
}
return layer.hasCompositedScrollableOverflow();
}
IndirectCompositingReason RenderLayerCompositor::computeIndirectCompositingReason(const RenderLayer& layer, bool hasCompositedDescendants, bool has3DTransformedDescendants, bool paintsIntoProvidedBacking) const
{
// When a layer has composited descendants, some effects, like 2d transforms, filters, masks etc must be implemented
// via compositing so that they also apply to those composited descendants.
auto& renderer = layer.renderer();
if (hasCompositedDescendants && (layer.isolatesCompositedBlending() || layer.transform() || renderer.createsGroup() || renderer.hasReflection()))
return IndirectCompositingReason::GraphicalEffect;
// A layer with preserve-3d or perspective only needs to be composited if there are descendant layers that
// will be affected by the preserve-3d or perspective.
if (has3DTransformedDescendants) {
if (renderer.style().preserves3D())
return IndirectCompositingReason::Preserve3D;
if (renderer.style().hasPerspective())
return IndirectCompositingReason::Perspective;
}
// If this layer scrolls independently from the layer that it would paint into, it needs to get composited.
if (!paintsIntoProvidedBacking && layer.hasCompositedScrollingAncestor()) {
auto* paintDestination = layer.paintOrderParent();
if (paintDestination && layerScrollBehahaviorRelativeToCompositedAncestor(layer, *paintDestination) != ScrollPositioningBehavior::None)
return IndirectCompositingReason::OverflowScrollPositioning;
}
// Check for clipping last; if compositing just for clipping, the layer doesn't need its own backing store.
if (hasCompositedDescendants && clipsCompositingDescendants(layer))
return IndirectCompositingReason::Clipping;
return IndirectCompositingReason::None;
}
bool RenderLayerCompositor::styleChangeMayAffectIndirectCompositingReasons(const RenderStyle& oldStyle, const RenderStyle& newStyle)
{
if (RenderElement::createsGroupForStyle(newStyle) != RenderElement::createsGroupForStyle(oldStyle))
return true;
if (newStyle.isolation() != oldStyle.isolation())
return true;
if (newStyle.hasTransform() != oldStyle.hasTransform())
return true;
if (newStyle.boxReflect() != oldStyle.boxReflect())
return true;
if (newStyle.usedTransformStyle3D() != oldStyle.usedTransformStyle3D())
return true;
if (newStyle.hasPerspective() != oldStyle.hasPerspective())
return true;
return false;
}
bool RenderLayerCompositor::isAsyncScrollableStickyLayer(const RenderLayer& layer, const RenderLayer** enclosingAcceleratedOverflowLayer) const
{
ASSERT(layer.renderer().isStickilyPositioned());
auto* enclosingOverflowLayer = layer.enclosingOverflowClipLayer(ExcludeSelf);
if (enclosingOverflowLayer && enclosingOverflowLayer->hasCompositedScrollableOverflow()) {
if (enclosingAcceleratedOverflowLayer)
*enclosingAcceleratedOverflowLayer = enclosingOverflowLayer;
return true;
}
// If the layer is inside normal overflow, it's not async-scrollable.
if (enclosingOverflowLayer)
return false;
// No overflow ancestor, so see if the frame supports async scrolling.
if (hasCoordinatedScrolling())
return true;
#if PLATFORM(IOS_FAMILY)
// iOS WK1 has fixed/sticky support in the main frame via WebFixedPositionContent.
return isMainFrameCompositor();
#else
return false;
#endif
}
bool RenderLayerCompositor::isViewportConstrainedFixedOrStickyLayer(const RenderLayer& layer) const
{
if (layer.renderer().isStickilyPositioned())
return isAsyncScrollableStickyLayer(layer);
if (!layer.renderer().isFixedPositioned())
return false;
// FIXME: Handle fixed inside of a transform, which should not behave as fixed.
for (auto* ancestor = layer.parent(); ancestor; ancestor = ancestor->parent()) {
if (ancestor->hasCompositedScrollableOverflow())
return true;
if (ancestor->isStackingContext() && ancestor->isComposited() && ancestor->renderer().isFixedPositioned())
return false;
}
return true;
}
bool RenderLayerCompositor::fixedLayerIntersectsViewport(const RenderLayer& layer) const
{
ASSERT(layer.renderer().isFixedPositioned());
// Fixed position elements that are invisible in the current view don't get their own layer.
// FIXME: We shouldn't have to check useFixedLayout() here; one of the viewport rects needs to give the correct answer.
LayoutRect viewBounds;
if (m_renderView.frameView().useFixedLayout())
viewBounds = m_renderView.unscaledDocumentRect();
else
viewBounds = m_renderView.frameView().rectForFixedPositionLayout();
LayoutRect layerBounds = layer.calculateLayerBounds(&layer, LayoutSize(), { RenderLayer::UseLocalClipRectIfPossible, RenderLayer::IncludeFilterOutsets, RenderLayer::UseFragmentBoxesExcludingCompositing,
RenderLayer::ExcludeHiddenDescendants, RenderLayer::DontConstrainForMask, RenderLayer::IncludeCompositedDescendants });
// Map to m_renderView to ignore page scale.
FloatRect absoluteBounds = layer.renderer().localToContainerQuad(FloatRect(layerBounds), &m_renderView).boundingBox();
return viewBounds.intersects(enclosingIntRect(absoluteBounds));
}
bool RenderLayerCompositor::useCoordinatedScrollingForLayer(const RenderLayer& layer) const
{
if (layer.isRenderViewLayer() && hasCoordinatedScrolling())
return true;
if (auto* scrollingCoordinator = this->scrollingCoordinator())
return scrollingCoordinator->coordinatesScrollingForOverflowLayer(layer);
return false;
}
ScrollPositioningBehavior RenderLayerCompositor::layerScrollBehahaviorRelativeToCompositedAncestor(const RenderLayer& layer, const RenderLayer& compositedAncestor)
{
if (!layer.hasCompositedScrollingAncestor())
return ScrollPositioningBehavior::None;
auto needsMovesNode = [&] {
bool result = false;
traverseAncestorLayers(layer, [&](const RenderLayer& ancestorLayer, bool isContainingBlockChain, bool /* isPaintOrderAncestor */) {
if (&ancestorLayer == &compositedAncestor)
return AncestorTraversal::Stop;
if (isContainingBlockChain && ancestorLayer.hasCompositedScrollableOverflow()) {
result = true;
return AncestorTraversal::Stop;
}
return AncestorTraversal::Continue;
});
return result;
};
if (needsMovesNode())
return ScrollPositioningBehavior::Moves;
if (layer.boxScrollingScope() != compositedAncestor.contentsScrollingScope())
return ScrollPositioningBehavior::Stationary;
return ScrollPositioningBehavior::None;
}
static void collectStationaryLayerRelatedOverflowNodes(const RenderLayer& layer, const RenderLayer&, Vector<ScrollingNodeID>& scrollingNodes)
{
ASSERT(layer.isComposited());
auto appendOverflowLayerNodeID = [&scrollingNodes] (const RenderLayer& overflowLayer) {
ASSERT(overflowLayer.isComposited());
auto scrollingNodeID = overflowLayer.backing()->scrollingNodeIDForRole(ScrollCoordinationRole::Scrolling);
if (scrollingNodeID)
scrollingNodes.append(scrollingNodeID);
else
LOG(Scrolling, "Layer %p doesn't have scrolling node ID yet", &overflowLayer);
};
// Collect all the composited scrollers which affect the position of this layer relative to its compositing ancestor (which might be inside the scroller or the scroller itself).
bool seenPaintOrderAncestor = false;
traverseAncestorLayers(layer, [&](const RenderLayer& ancestorLayer, bool isContainingBlockChain, bool isPaintOrderAncestor) {
seenPaintOrderAncestor |= isPaintOrderAncestor;
if (isContainingBlockChain && isPaintOrderAncestor)
return AncestorTraversal::Stop;
if (!ancestorLayer.isComposited())
return AncestorTraversal::Stop;
if (seenPaintOrderAncestor && !isContainingBlockChain && ancestorLayer.hasCompositedScrollableOverflow())
appendOverflowLayerNodeID(ancestorLayer);
return AncestorTraversal::Continue;
});
}
ScrollPositioningBehavior RenderLayerCompositor::computeCoordinatedPositioningForLayer(const RenderLayer& layer, const RenderLayer* compositedAncestor) const
{
if (layer.isRenderViewLayer())
return ScrollPositioningBehavior::None;
if (layer.renderer().isFixedPositioned())
return ScrollPositioningBehavior::None;
if (!layer.hasCompositedScrollingAncestor())
return ScrollPositioningBehavior::None;
auto* scrollingCoordinator = this->scrollingCoordinator();
if (!scrollingCoordinator)
return ScrollPositioningBehavior::None;
if (!compositedAncestor) {
ASSERT_NOT_REACHED();
return ScrollPositioningBehavior::None;
}
return layerScrollBehahaviorRelativeToCompositedAncestor(layer, *compositedAncestor);
}
static Vector<ScrollingNodeID> collectRelatedCoordinatedScrollingNodes(const RenderLayer& layer, ScrollPositioningBehavior positioningBehavior)
{
Vector<ScrollingNodeID> overflowNodeIDs;
switch (positioningBehavior) {
case ScrollPositioningBehavior::Stationary: {
auto* compositedAncestor = layer.ancestorCompositingLayer();
if (!compositedAncestor)
return overflowNodeIDs;
collectStationaryLayerRelatedOverflowNodes(layer, *compositedAncestor, overflowNodeIDs);
break;
}
case ScrollPositioningBehavior::Moves:
case ScrollPositioningBehavior::None:
ASSERT_NOT_REACHED();
break;
}
return overflowNodeIDs;
}
bool RenderLayerCompositor::isLayerForIFrameWithScrollCoordinatedContents(const RenderLayer& layer) const
{
if (!is<RenderWidget>(layer.renderer()))
return false;
auto* contentDocument = downcast<RenderWidget>(layer.renderer()).frameOwnerElement().contentDocument();
if (!contentDocument)
return false;
auto* view = contentDocument->renderView();
if (!view)
return false;
if (auto* scrollingCoordinator = this->scrollingCoordinator())
return scrollingCoordinator->coordinatesScrollingForFrameView(view->frameView());
return false;
}
bool RenderLayerCompositor::isRunningTransformAnimation(RenderLayerModelObject& renderer) const
{
if (!(m_compositingTriggers & ChromeClient::AnimationTrigger))
return false;
if (auto styleable = Styleable::fromRenderer(renderer)) {
if (auto* effectsStack = styleable->keyframeEffectStack())
return effectsStack->isCurrentlyAffectingProperty(CSSPropertyTransform)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyRotate)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyScale)
|| effectsStack->isCurrentlyAffectingProperty(CSSPropertyTranslate);
}
return false;
}
// If an element has composited 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
{
for (auto* layer : layer.negativeZOrderLayers()) {
if (layer->isComposited() || layer->hasCompositingDescendant())
return true;
}
return false;
}
bool RenderLayerCompositor::requiresScrollLayer(RootLayerAttachment attachment) const
{
auto& frameView = m_renderView.frameView();
// This applies when the application UI handles scrolling, in which case RenderLayerCompositor doesn't need to manage it.
if (frameView.delegatesScrolling() && isMainFrameCompositor())
return false;
// We need to handle our own scrolling if we're:
return !m_renderView.frameView().platformWidget() // viewless (i.e. non-Mac, or Mac in WebKit2)
|| attachment == RootLayerAttachedViaEnclosingFrame; // a composited frame on Mac
}
void paintScrollbar(Scrollbar* scrollbar, GraphicsContext& context, const IntRect& clip)
{
if (!scrollbar)
return;
context.save();
const IntRect& scrollbarRect = scrollbar->frameRect();
context.translate(-scrollbarRect.location());
IntRect transformedClip = clip;
transformedClip.moveBy(scrollbarRect.location());
scrollbar->paint(context, transformedClip);
context.restore();
}
void RenderLayerCompositor::paintContents(const GraphicsLayer* graphicsLayer, GraphicsContext& context, const FloatRect& clip, GraphicsLayerPaintBehavior)
{
#if PLATFORM(MAC)
LocalDefaultSystemAppearance localAppearance(m_renderView.useDarkAppearance());
#endif
IntRect pixelSnappedRectForIntegralPositionedItems = snappedIntRect(LayoutRect(clip));
if (graphicsLayer == layerForHorizontalScrollbar())
paintScrollbar(m_renderView.frameView().horizontalScrollbar(), context, pixelSnappedRectForIntegralPositionedItems);
else if (graphicsLayer == layerForVerticalScrollbar())
paintScrollbar(m_renderView.frameView().verticalScrollbar(), context, pixelSnappedRectForIntegralPositionedItems);
else if (graphicsLayer == layerForScrollCorner()) {
const IntRect& scrollCorner = m_renderView.frameView().scrollCornerRect();
context.save();
context.translate(-scrollCorner.location());
IntRect transformedClip = pixelSnappedRectForIntegralPositionedItems;
transformedClip.moveBy(scrollCorner.location());
m_renderView.frameView().paintScrollCorner(context, transformedClip);
context.restore();
}
}
bool RenderLayerCompositor::supportsFixedRootBackgroundCompositing() const
{
auto* renderViewBacking = m_renderView.layer()->backing();
return renderViewBacking && renderViewBacking->isFrameLayerWithTiledBacking();
}
bool RenderLayerCompositor::needsFixedRootBackgroundLayer(const RenderLayer& layer) const
{
if (!layer.isRenderViewLayer())
return false;
if (m_renderView.settings().fixedBackgroundsPaintRelativeToDocument())
return false;
return supportsFixedRootBackgroundCompositing() && m_renderView.rootBackgroundIsEntirelyFixed();
}
GraphicsLayer* RenderLayerCompositor::fixedRootBackgroundLayer() const
{
// Get the fixed root background from the RenderView layer's backing.
auto* viewLayer = m_renderView.layer();
if (!viewLayer)
return nullptr;
if (viewLayer->isComposited() && viewLayer->backing()->backgroundLayerPaintsFixedRootBackground())
return viewLayer->backing()->backgroundLayer();
return nullptr;
}
void RenderLayerCompositor::resetTrackedRepaintRects()
{
if (auto* rootLayer = rootGraphicsLayer()) {
GraphicsLayer::traverse(*rootLayer, [](GraphicsLayer& layer) {
layer.resetTrackedRepaints();
});
}
}
float RenderLayerCompositor::deviceScaleFactor() const
{
return m_renderView.document().deviceScaleFactor();
}
float RenderLayerCompositor::pageScaleFactor() const
{
return page().pageScaleFactor();
}
float RenderLayerCompositor::zoomedOutPageScaleFactor() const
{
return page().zoomedOutPageScaleFactor();
}
float RenderLayerCompositor::contentsScaleMultiplierForNewTiles(const GraphicsLayer*) const
{
#if PLATFORM(IOS_FAMILY)
LegacyTileCache* tileCache = nullptr;
if (auto* frameView = page().mainFrame().view())
tileCache = frameView->legacyTileCache();
if (!tileCache)
return 1;
return tileCache->tileControllerShouldUseLowScaleTiles() ? 0.125 : 1;
#else
return 1;
#endif
}
bool RenderLayerCompositor::documentUsesTiledBacking() const
{
auto* layer = m_renderView.layer();
if (!layer)
return false;
auto* backing = layer->backing();
if (!backing)
return false;
return backing->isFrameLayerWithTiledBacking();
}
bool RenderLayerCompositor::isMainFrameCompositor() const
{
return m_renderView.frameView().frame().isMainFrame();
}
bool RenderLayerCompositor::shouldCompositeOverflowControls() const
{
auto& frameView = m_renderView.frameView();
if (!frameView.managesScrollbars())
return false;
if (documentUsesTiledBacking())
return true;
if (m_overflowControlsHostLayer && isMainFrameCompositor())
return true;
#if !USE(COORDINATED_GRAPHICS)
if (!frameView.hasOverlayScrollbars())
return false;
#endif
return true;
}
bool RenderLayerCompositor::requiresHorizontalScrollbarLayer() const
{
return shouldCompositeOverflowControls() && m_renderView.frameView().horizontalScrollbar();
}
bool RenderLayerCompositor::requiresVerticalScrollbarLayer() const
{
return shouldCompositeOverflowControls() && m_renderView.frameView().verticalScrollbar();
}
bool RenderLayerCompositor::requiresScrollCornerLayer() const
{
return shouldCompositeOverflowControls() && m_renderView.frameView().isScrollCornerVisible();
}
#if HAVE(RUBBER_BANDING)
bool RenderLayerCompositor::requiresOverhangAreasLayer() const
{
if (!isMainFrameCompositor())
return false;
// We do want a layer if we're using tiled drawing and can scroll.
if (documentUsesTiledBacking() && m_renderView.frameView().hasOpaqueBackground() && !m_renderView.frameView().prohibitsScrolling())
return true;
return false;
}
bool RenderLayerCompositor::requiresContentShadowLayer() const
{
if (!isMainFrameCompositor())
return false;
#if PLATFORM(COCOA)
if (viewHasTransparentBackground())
return false;
// If the background is going to extend, then it doesn't make sense to have a shadow layer.
if (m_renderView.settings().backgroundShouldExtendBeyondPage())
return false;
// On Mac, we want a content shadow layer if we're using tiled drawing and can scroll.
if (documentUsesTiledBacking() && !m_renderView.frameView().prohibitsScrolling())
return true;
#endif
return false;
}
GraphicsLayer* RenderLayerCompositor::updateLayerForTopOverhangArea(bool wantsLayer)
{
if (!isMainFrameCompositor())
return nullptr;
if (!wantsLayer) {
GraphicsLayer::unparentAndClear(m_layerForTopOverhangArea);
return nullptr;
}
if (!m_layerForTopOverhangArea) {
m_layerForTopOverhangArea = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_layerForTopOverhangArea->setName(MAKE_STATIC_STRING_IMPL("top overhang"));
m_scrolledContentsLayer->addChildBelow(*m_layerForTopOverhangArea, m_rootContentsLayer.get());
}
return m_layerForTopOverhangArea.get();
}
GraphicsLayer* RenderLayerCompositor::updateLayerForBottomOverhangArea(bool wantsLayer)
{
if (!isMainFrameCompositor())
return nullptr;
if (!wantsLayer) {
GraphicsLayer::unparentAndClear(m_layerForBottomOverhangArea);
return nullptr;
}
if (!m_layerForBottomOverhangArea) {
m_layerForBottomOverhangArea = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_layerForBottomOverhangArea->setName(MAKE_STATIC_STRING_IMPL("bottom overhang"));
m_scrolledContentsLayer->addChildBelow(*m_layerForBottomOverhangArea, m_rootContentsLayer.get());
}
m_layerForBottomOverhangArea->setPosition(FloatPoint(0, m_rootContentsLayer->size().height() + m_renderView.frameView().headerHeight()
+ m_renderView.frameView().footerHeight() + m_renderView.frameView().topContentInset()));
return m_layerForBottomOverhangArea.get();
}
GraphicsLayer* RenderLayerCompositor::updateLayerForHeader(bool wantsLayer)
{
if (!isMainFrameCompositor())
return nullptr;
if (!wantsLayer) {
if (m_layerForHeader) {
GraphicsLayer::unparentAndClear(m_layerForHeader);
// The ScrollingTree knows about the header layer, and the position of the root layer is affected
// by the header layer, so if we remove the header, we need to tell the scrolling tree.
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->frameViewRootLayerDidChange(m_renderView.frameView());
}
return nullptr;
}
if (!m_layerForHeader) {
m_layerForHeader = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_layerForHeader->setName(MAKE_STATIC_STRING_IMPL("header"));
m_scrolledContentsLayer->addChildAbove(*m_layerForHeader, m_rootContentsLayer.get());
m_renderView.frameView().addPaintPendingMilestones(DidFirstFlushForHeaderLayer);
}
m_layerForHeader->setPosition(FloatPoint(0,
FrameView::yPositionForHeaderLayer(m_renderView.frameView().scrollPosition(), m_renderView.frameView().topContentInset())));
m_layerForHeader->setAnchorPoint(FloatPoint3D());
m_layerForHeader->setSize(FloatSize(m_renderView.frameView().visibleWidth(), m_renderView.frameView().headerHeight()));
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->frameViewRootLayerDidChange(m_renderView.frameView());
page().chrome().client().didAddHeaderLayer(*m_layerForHeader);
return m_layerForHeader.get();
}
GraphicsLayer* RenderLayerCompositor::updateLayerForFooter(bool wantsLayer)
{
if (!isMainFrameCompositor())
return nullptr;
if (!wantsLayer) {
if (m_layerForFooter) {
GraphicsLayer::unparentAndClear(m_layerForFooter);
// The ScrollingTree knows about the footer layer, and the total scrollable size is affected
// by the footer layer, so if we remove the footer, we need to tell the scrolling tree.
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->frameViewRootLayerDidChange(m_renderView.frameView());
}
return nullptr;
}
if (!m_layerForFooter) {
m_layerForFooter = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_layerForFooter->setName(MAKE_STATIC_STRING_IMPL("footer"));
m_scrolledContentsLayer->addChildAbove(*m_layerForFooter, m_rootContentsLayer.get());
}
float totalContentHeight = m_rootContentsLayer->size().height() + m_renderView.frameView().headerHeight() + m_renderView.frameView().footerHeight();
m_layerForFooter->setPosition(FloatPoint(0, FrameView::yPositionForFooterLayer(m_renderView.frameView().scrollPosition(),
m_renderView.frameView().topContentInset(), totalContentHeight, m_renderView.frameView().footerHeight())));
m_layerForFooter->setAnchorPoint(FloatPoint3D());
m_layerForFooter->setSize(FloatSize(m_renderView.frameView().visibleWidth(), m_renderView.frameView().footerHeight()));
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->frameViewRootLayerDidChange(m_renderView.frameView());
page().chrome().client().didAddFooterLayer(*m_layerForFooter);
return m_layerForFooter.get();
}
void RenderLayerCompositor::updateLayerForOverhangAreasBackgroundColor()
{
if (!m_layerForOverhangAreas)
return;
Color backgroundColor;
if (m_renderView.settings().backgroundShouldExtendBeyondPage()) {
backgroundColor = ([&] {
if (auto underPageBackgroundColorOverride = page().underPageBackgroundColorOverride(); underPageBackgroundColorOverride.isValid())
return underPageBackgroundColorOverride;
return m_rootExtendedBackgroundColor;
})();
m_layerForOverhangAreas->setBackgroundColor(backgroundColor);
}
if (!backgroundColor.isValid())
m_layerForOverhangAreas->setCustomAppearance(GraphicsLayer::CustomAppearance::ScrollingOverhang);
}
#endif // HAVE(RUBBER_BANDING)
bool RenderLayerCompositor::viewNeedsToInvalidateEventRegionOfEnclosingCompositingLayerForRepaint() const
{
// Event regions are only updated on compositing layers. Non-composited layers must
// delegate to their enclosing compositing layer for repaint to update the event region
// for elements inside them.
return !m_renderView.isComposited();
}
bool RenderLayerCompositor::viewHasTransparentBackground(Color* backgroundColor) const
{
if (m_renderView.frameView().isTransparent()) {
if (backgroundColor)
*backgroundColor = Color(); // Return an invalid color.
return true;
}
Color documentBackgroundColor = m_renderView.frameView().documentBackgroundColor();
if (!documentBackgroundColor.isValid())
documentBackgroundColor = m_renderView.frameView().baseBackgroundColor();
ASSERT(documentBackgroundColor.isValid());
if (backgroundColor)
*backgroundColor = documentBackgroundColor;
return !documentBackgroundColor.isOpaque();
}
// We can't rely on getting layerStyleChanged() for a style change that affects the root background, because the style change may
// be on the body which has no RenderLayer.
void RenderLayerCompositor::rootOrBodyStyleChanged(RenderElement& renderer, const RenderStyle* oldStyle)
{
if (!usesCompositing())
return;
Color oldBackgroundColor;
if (oldStyle)
oldBackgroundColor = oldStyle->visitedDependentColorWithColorFilter(CSSPropertyBackgroundColor);
if (oldBackgroundColor != renderer.style().visitedDependentColorWithColorFilter(CSSPropertyBackgroundColor))
rootBackgroundColorOrTransparencyChanged();
bool hadFixedBackground = oldStyle && oldStyle->hasEntirelyFixedBackground();
if (hadFixedBackground != renderer.style().hasEntirelyFixedBackground())
rootLayerConfigurationChanged();
if (oldStyle && (oldStyle->overscrollBehaviorX() != renderer.style().overscrollBehaviorX() || oldStyle->overscrollBehaviorY() != renderer.style().overscrollBehaviorY())) {
if (auto* layer = m_renderView.layer())
layer->setNeedsCompositingGeometryUpdate();
}
}
void RenderLayerCompositor::rootBackgroundColorOrTransparencyChanged()
{
if (!usesCompositing())
return;
Color backgroundColor;
bool isTransparent = viewHasTransparentBackground(&backgroundColor);
Color extendedBackgroundColor = m_renderView.settings().backgroundShouldExtendBeyondPage() ? backgroundColor : Color();
bool transparencyChanged = m_viewBackgroundIsTransparent != isTransparent;
bool backgroundColorChanged = m_viewBackgroundColor != backgroundColor;
bool extendedBackgroundColorChanged = m_rootExtendedBackgroundColor != extendedBackgroundColor;
if (!transparencyChanged && !backgroundColorChanged && !extendedBackgroundColorChanged)
return;
LOG(Compositing, "RenderLayerCompositor %p rootBackgroundColorOrTransparencyChanged. isTransparent=%d", this, isTransparent);
m_viewBackgroundIsTransparent = isTransparent;
m_viewBackgroundColor = backgroundColor;
m_rootExtendedBackgroundColor = extendedBackgroundColor;
if (extendedBackgroundColorChanged) {
page().chrome().client().pageExtendedBackgroundColorDidChange();
#if HAVE(RUBBER_BANDING)
updateLayerForOverhangAreasBackgroundColor();
#endif
}
rootLayerConfigurationChanged();
}
void RenderLayerCompositor::updateOverflowControlsLayers()
{
#if HAVE(RUBBER_BANDING)
if (requiresOverhangAreasLayer()) {
if (!m_layerForOverhangAreas) {
m_layerForOverhangAreas = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_layerForOverhangAreas->setName(MAKE_STATIC_STRING_IMPL("overhang areas"));
m_layerForOverhangAreas->setDrawsContent(false);
float topContentInset = m_renderView.frameView().topContentInset();
IntSize overhangAreaSize = m_renderView.frameView().frameRect().size();
overhangAreaSize.setHeight(overhangAreaSize.height() - topContentInset);
m_layerForOverhangAreas->setSize(overhangAreaSize);
m_layerForOverhangAreas->setPosition(FloatPoint(0, topContentInset));
m_layerForOverhangAreas->setAnchorPoint(FloatPoint3D());
updateLayerForOverhangAreasBackgroundColor();
// We want the overhang areas layer to be positioned below the frame contents,
// so insert it below the clip layer.
m_overflowControlsHostLayer->addChildBelow(*m_layerForOverhangAreas, layerForClipping());
}
} else
GraphicsLayer::unparentAndClear(m_layerForOverhangAreas);
if (requiresContentShadowLayer()) {
if (!m_contentShadowLayer) {
m_contentShadowLayer = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_contentShadowLayer->setName(MAKE_STATIC_STRING_IMPL("content shadow"));
m_contentShadowLayer->setSize(m_rootContentsLayer->size());
m_contentShadowLayer->setPosition(m_rootContentsLayer->position());
m_contentShadowLayer->setAnchorPoint(FloatPoint3D());
m_contentShadowLayer->setCustomAppearance(GraphicsLayer::CustomAppearance::ScrollingShadow);
m_scrolledContentsLayer->addChildBelow(*m_contentShadowLayer, m_rootContentsLayer.get());
}
} else
GraphicsLayer::unparentAndClear(m_contentShadowLayer);
#endif
if (requiresHorizontalScrollbarLayer()) {
if (!m_layerForHorizontalScrollbar) {
m_layerForHorizontalScrollbar = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_layerForHorizontalScrollbar->setAllowsBackingStoreDetaching(false);
m_layerForHorizontalScrollbar->setAllowsTiling(false);
m_layerForHorizontalScrollbar->setShowDebugBorder(m_showDebugBorders);
m_layerForHorizontalScrollbar->setName(MAKE_STATIC_STRING_IMPL("horizontal scrollbar container"));
#if PLATFORM(COCOA) && USE(CA)
m_layerForHorizontalScrollbar->setAcceleratesDrawing(acceleratedDrawingEnabled());
#endif
m_overflowControlsHostLayer->addChild(*m_layerForHorizontalScrollbar);
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->scrollableAreaScrollbarLayerDidChange(m_renderView.frameView(), ScrollbarOrientation::Horizontal);
}
} else if (m_layerForHorizontalScrollbar) {
GraphicsLayer::unparentAndClear(m_layerForHorizontalScrollbar);
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->scrollableAreaScrollbarLayerDidChange(m_renderView.frameView(), ScrollbarOrientation::Horizontal);
}
if (requiresVerticalScrollbarLayer()) {
if (!m_layerForVerticalScrollbar) {
m_layerForVerticalScrollbar = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_layerForVerticalScrollbar->setAllowsBackingStoreDetaching(false);
m_layerForVerticalScrollbar->setAllowsTiling(false);
m_layerForVerticalScrollbar->setShowDebugBorder(m_showDebugBorders);
m_layerForVerticalScrollbar->setName(MAKE_STATIC_STRING_IMPL("vertical scrollbar container"));
#if PLATFORM(COCOA) && USE(CA)
m_layerForVerticalScrollbar->setAcceleratesDrawing(acceleratedDrawingEnabled());
#endif
m_overflowControlsHostLayer->addChild(*m_layerForVerticalScrollbar);
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->scrollableAreaScrollbarLayerDidChange(m_renderView.frameView(), ScrollbarOrientation::Vertical);
}
} else if (m_layerForVerticalScrollbar) {
GraphicsLayer::unparentAndClear(m_layerForVerticalScrollbar);
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->scrollableAreaScrollbarLayerDidChange(m_renderView.frameView(), ScrollbarOrientation::Vertical);
}
if (requiresScrollCornerLayer()) {
if (!m_layerForScrollCorner) {
m_layerForScrollCorner = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_layerForScrollCorner->setAllowsBackingStoreDetaching(false);
m_layerForScrollCorner->setShowDebugBorder(m_showDebugBorders);
m_layerForScrollCorner->setName(MAKE_STATIC_STRING_IMPL("scroll corner"));
#if PLATFORM(COCOA) && USE(CA)
m_layerForScrollCorner->setAcceleratesDrawing(acceleratedDrawingEnabled());
#endif
m_overflowControlsHostLayer->addChild(*m_layerForScrollCorner);
}
} else
GraphicsLayer::unparentAndClear(m_layerForScrollCorner);
m_renderView.frameView().positionScrollbarLayers();
}
void RenderLayerCompositor::ensureRootLayer()
{
RootLayerAttachment expectedAttachment = isMainFrameCompositor() ? RootLayerAttachedViaChromeClient : RootLayerAttachedViaEnclosingFrame;
if (expectedAttachment == m_rootLayerAttachment)
return;
if (!m_rootContentsLayer) {
m_rootContentsLayer = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_rootContentsLayer->setName(MAKE_STATIC_STRING_IMPL("content root"));
IntRect overflowRect = snappedIntRect(m_renderView.layoutOverflowRect());
m_rootContentsLayer->setSize(FloatSize(overflowRect.maxX(), overflowRect.maxY()));
m_rootContentsLayer->setPosition(FloatPoint());
#if PLATFORM(IOS_FAMILY)
// Page scale is applied above this on iOS, so we'll just say that our root layer applies it.
auto& frame = m_renderView.frameView().frame();
if (frame.isMainFrame())
m_rootContentsLayer->setAppliesPageScale();
#endif
// Need to clip to prevent transformed content showing outside this frame
updateRootContentLayerClipping();
}
if (requiresScrollLayer(expectedAttachment)) {
if (!m_overflowControlsHostLayer) {
ASSERT(!m_scrolledContentsLayer);
ASSERT(!m_clipLayer);
// Create a layer to host the clipping layer and the overflow controls layers.
m_overflowControlsHostLayer = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_overflowControlsHostLayer->setName(MAKE_STATIC_STRING_IMPL("overflow controls host"));
m_scrolledContentsLayer = GraphicsLayer::create(graphicsLayerFactory(), *this, GraphicsLayer::Type::ScrolledContents);
m_scrolledContentsLayer->setName(MAKE_STATIC_STRING_IMPL("frame scrolled contents"));
m_scrolledContentsLayer->setAnchorPoint({ });
#if PLATFORM(IOS_FAMILY)
if (m_renderView.settings().asyncFrameScrollingEnabled()) {
m_scrollContainerLayer = GraphicsLayer::create(graphicsLayerFactory(), *this, GraphicsLayer::Type::ScrollContainer);
m_scrollContainerLayer->setName(MAKE_STATIC_STRING_IMPL("scroll container"));
m_scrollContainerLayer->setMasksToBounds(true);
m_scrollContainerLayer->setAnchorPoint({ });
m_scrollContainerLayer->addChild(*m_scrolledContentsLayer);
m_overflowControlsHostLayer->addChild(*m_scrollContainerLayer);
}
#endif
// FIXME: m_scrollContainerLayer and m_clipLayer have similar roles here, but m_clipLayer has some special positioning to
// account for clipping and top content inset (see FrameView::yPositionForInsetClipLayer()).
if (!m_scrollContainerLayer) {
m_clipLayer = GraphicsLayer::create(graphicsLayerFactory(), *this);
m_clipLayer->setName(MAKE_STATIC_STRING_IMPL("frame clipping"));
m_clipLayer->setMasksToBounds(true);
m_clipLayer->setAnchorPoint({ });
m_clipLayer->addChild(*m_scrolledContentsLayer);
m_overflowControlsHostLayer->addChild(*m_clipLayer);
}
m_scrolledContentsLayer->addChild(*m_rootContentsLayer);
updateScrollLayerClipping();
updateOverflowControlsLayers();
if (hasCoordinatedScrolling())
scheduleRenderingUpdate();
else
updateScrollLayerPosition();
}
} else {
if (m_overflowControlsHostLayer) {
GraphicsLayer::unparentAndClear(m_overflowControlsHostLayer);
GraphicsLayer::unparentAndClear(m_clipLayer);
GraphicsLayer::unparentAndClear(m_scrollContainerLayer);
GraphicsLayer::unparentAndClear(m_scrolledContentsLayer);
}
}
// Check to see if we have to change the attachment
if (m_rootLayerAttachment != RootLayerUnattached)
detachRootLayer();
attachRootLayer(expectedAttachment);
}
void RenderLayerCompositor::destroyRootLayer()
{
if (!m_rootContentsLayer)
return;
detachRootLayer();
#if HAVE(RUBBER_BANDING)
GraphicsLayer::unparentAndClear(m_layerForOverhangAreas);
#endif
if (m_layerForHorizontalScrollbar) {
GraphicsLayer::unparentAndClear(m_layerForHorizontalScrollbar);
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->scrollableAreaScrollbarLayerDidChange(m_renderView.frameView(), ScrollbarOrientation::Horizontal);
if (auto* horizontalScrollbar = m_renderView.frameView().verticalScrollbar())
m_renderView.frameView().invalidateScrollbar(*horizontalScrollbar, IntRect(IntPoint(0, 0), horizontalScrollbar->frameRect().size()));
}
if (m_layerForVerticalScrollbar) {
GraphicsLayer::unparentAndClear(m_layerForVerticalScrollbar);
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->scrollableAreaScrollbarLayerDidChange(m_renderView.frameView(), ScrollbarOrientation::Vertical);
if (auto* verticalScrollbar = m_renderView.frameView().verticalScrollbar())
m_renderView.frameView().invalidateScrollbar(*verticalScrollbar, IntRect(IntPoint(0, 0), verticalScrollbar->frameRect().size()));
}
if (m_layerForScrollCorner) {
GraphicsLayer::unparentAndClear(m_layerForScrollCorner);
m_renderView.frameView().invalidateScrollCorner(m_renderView.frameView().scrollCornerRect());
}
if (m_overflowControlsHostLayer) {
GraphicsLayer::unparentAndClear(m_overflowControlsHostLayer);
GraphicsLayer::unparentAndClear(m_clipLayer);
GraphicsLayer::unparentAndClear(m_scrollContainerLayer);
GraphicsLayer::unparentAndClear(m_scrolledContentsLayer);
}
ASSERT(!m_scrolledContentsLayer);
GraphicsLayer::unparentAndClear(m_rootContentsLayer);
m_layerUpdater = nullptr;
}
void RenderLayerCompositor::attachRootLayer(RootLayerAttachment attachment)
{
if (!m_rootContentsLayer)
return;
LOG(Compositing, "RenderLayerCompositor %p attachRootLayer %d", this, attachment);
switch (attachment) {
case RootLayerUnattached:
ASSERT_NOT_REACHED();
break;
case RootLayerAttachedViaChromeClient: {
auto& frame = m_renderView.frameView().frame();
page().chrome().client().attachRootGraphicsLayer(frame, rootGraphicsLayer());
break;
}
case RootLayerAttachedViaEnclosingFrame: {
// The layer will get hooked up via RenderLayerBacking::updateConfiguration()
// for the frame's renderer in the parent document.
if (auto* ownerElement = m_renderView.document().ownerElement())
ownerElement->scheduleInvalidateStyleAndLayerComposition();
break;
}
}
m_rootLayerAttachment = attachment;
rootLayerAttachmentChanged();
if (m_shouldFlushOnReattach) {
scheduleRenderingUpdate();
m_shouldFlushOnReattach = false;
}
}
void RenderLayerCompositor::detachRootLayer()
{
if (!m_rootContentsLayer || m_rootLayerAttachment == RootLayerUnattached)
return;
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->frameViewWillBeDetached(m_renderView.frameView());
switch (m_rootLayerAttachment) {
case RootLayerAttachedViaEnclosingFrame: {
// The layer will get unhooked up via RenderLayerBacking::updateConfiguration()
// for the frame's renderer in the parent document.
if (m_overflowControlsHostLayer)
m_overflowControlsHostLayer->removeFromParent();
else
m_rootContentsLayer->removeFromParent();
if (auto* ownerElement = m_renderView.document().ownerElement())
ownerElement->scheduleInvalidateStyleAndLayerComposition();
if (auto frameRootScrollingNodeID = m_renderView.frameView().scrollingNodeID()) {
if (auto* scrollingCoordinator = this->scrollingCoordinator()) {
scrollingCoordinator->frameViewWillBeDetached(m_renderView.frameView());
scrollingCoordinator->unparentNode(frameRootScrollingNodeID);
}
}
break;
}
case RootLayerAttachedViaChromeClient: {
auto& frame = m_renderView.frameView().frame();
if (auto* scrollingCoordinator = this->scrollingCoordinator())
scrollingCoordinator->frameViewWillBeDetached(m_renderView.frameView());
page().chrome().client().attachRootGraphicsLayer(frame, nullptr);
}
break;
case RootLayerUnattached:
break;
}
m_rootLayerAttachment = RootLayerUnattached;
rootLayerAttachmentChanged();
}
void RenderLayerCompositor::updateRootLayerAttachment()
{
ensureRootLayer();
}
void RenderLayerCompositor::rootLayerAttachmentChanged()
{
// The document-relative page overlay layer (which is pinned to the main frame's layer tree)
// is moved between different RenderLayerCompositors' layer trees, and needs to be
// reattached whenever we swap in a new RenderLayerCompositor.
if (m_rootLayerAttachment == RootLayerUnattached)
return;
auto& frame = m_renderView.frameView().frame();
// The attachment can affect whether the RenderView layer's paintsIntoWindow() behavior,
// so call updateDrawsContent() to update that.
auto* layer = m_renderView.layer();
if (auto* backing = layer ? layer->backing() : nullptr)
backing->updateDrawsContent();
if (!frame.isMainFrame())
return;
Ref<GraphicsLayer> overlayHost = page().pageOverlayController().layerWithDocumentOverlays();
m_rootContentsLayer->addChild(WTFMove(overlayHost));
}
void RenderLayerCompositor::notifyIFramesOfCompositingChange()
{
// Compositing affects the answer to RenderIFrame::requiresAcceleratedCompositing(), so
// we need to schedule a style recalc in our parent document.
if (auto* ownerElement = m_renderView.document().ownerElement())
ownerElement->scheduleInvalidateStyleAndLayerComposition();
}
bool RenderLayerCompositor::layerHas3DContent(const RenderLayer& layer) const
{
const RenderStyle& style = layer.renderer().style();
if (style.preserves3D() || style.hasPerspective() || styleHas3DTransformOperation(style))
return true;
const_cast<RenderLayer&>(layer).updateLayerListsIfNeeded();
#if ASSERT_ENABLED
LayerListMutationDetector mutationChecker(const_cast<RenderLayer&>(layer));
#endif
for (auto* renderLayer : layer.negativeZOrderLayers()) {
if (layerHas3DContent(*renderLayer))
return true;
}
for (auto* renderLayer : layer.positiveZOrderLayers()) {
if (layerHas3DContent(*renderLayer))
return true;
}
for (auto* renderLayer : layer.normalFlowLayers()) {
if (layerHas3DContent(*renderLayer))
return true;
}
return false;
}
void RenderLayerCompositor::deviceOrPageScaleFactorChanged()
{
// Page scale will only be applied at to the RenderView and sublayers, but the device scale factor
// needs to be applied at the level of rootGraphicsLayer().
if (auto* rootLayer = rootGraphicsLayer())
rootLayer->noteDeviceOrPageScaleFactorChangedIncludingDescendants();
}
void RenderLayerCompositor::removeFromScrollCoordinatedLayers(RenderLayer& layer)
{
#if PLATFORM(IOS_FAMILY)
if (m_legacyScrollingLayerCoordinator)
m_legacyScrollingLayerCoordinator->removeLayer(layer);
#endif
detachScrollCoordinatedLayer(layer, allScrollCoordinationRoles());
}
FixedPositionViewportConstraints RenderLayerCompositor::computeFixedViewportConstraints(RenderLayer& layer) const
{
ASSERT(layer.isComposited());
auto* graphicsLayer = layer.backing()->graphicsLayer();
FixedPositionViewportConstraints constraints;
constraints.setLayerPositionAtLastLayout(graphicsLayer->position());
constraints.setViewportRectAtLastLayout(m_renderView.frameView().rectForFixedPositionLayout());
constraints.setAlignmentOffset(graphicsLayer->pixelAlignmentOffset());
const RenderStyle& style = layer.renderer().style();
if (!style.left().isAuto())
constraints.addAnchorEdge(ViewportConstraints::AnchorEdgeLeft);
if (!style.right().isAuto())
constraints.addAnchorEdge(ViewportConstraints::AnchorEdgeRight);
if (!style.top().isAuto())
constraints.addAnchorEdge(ViewportConstraints::AnchorEdgeTop);
if (!style.bottom().isAuto())
constraints.addAnchorEdge(ViewportConstraints::AnchorEdgeBottom);
// If left and right are auto, use left.
if (style.left().isAuto() && style.right().isAuto())
constraints.addAnchorEdge(ViewportConstraints::AnchorEdgeLeft);
// If top and bottom are auto, use top.
if (style.top().isAuto() && style.bottom().isAuto())
constraints.addAnchorEdge(ViewportConstraints::AnchorEdgeTop);
return constraints;
}
StickyPositionViewportConstraints RenderLayerCompositor::computeStickyViewportConstraints(RenderLayer& layer) const
{
ASSERT(layer.isComposited());
auto& renderer = downcast<RenderBoxModelObject>(layer.renderer());
StickyPositionViewportConstraints constraints;
renderer.computeStickyPositionConstraints(constraints, renderer.constrainingRectForStickyPosition());
auto* graphicsLayer = layer.backing()->graphicsLayer();
constraints.setLayerPositionAtLastLayout(graphicsLayer->position());
constraints.setStickyOffsetAtLastLayout(renderer.stickyPositionOffset());
constraints.setAlignmentOffset(graphicsLayer->pixelAlignmentOffset());
return constraints;
}
static inline ScrollCoordinationRole scrollCoordinationRoleForNodeType(ScrollingNodeType nodeType)
{
switch (nodeType) {
case ScrollingNodeType::MainFrame:
case ScrollingNodeType::Subframe:
case ScrollingNodeType::Overflow:
return ScrollCoordinationRole::Scrolling;
case ScrollingNodeType::OverflowProxy:
return ScrollCoordinationRole::ScrollingProxy;
case ScrollingNodeType::FrameHosting:
return ScrollCoordinationRole::FrameHosting;
case ScrollingNodeType::Fixed:
case ScrollingNodeType::Sticky:
return ScrollCoordinationRole::ViewportConstrained;
case ScrollingNodeType::Positioned:
return ScrollCoordinationRole::Positioning;
}
ASSERT_NOT_REACHED();
return ScrollCoordinationRole::Scrolling;
}
ScrollingNodeID RenderLayerCompositor::attachScrollingNode(RenderLayer& layer, ScrollingNodeType nodeType, ScrollingTreeState& treeState)
{
auto* scrollingCoordinator = this->scrollingCoordinator();
auto* backing = layer.backing();
// Crash logs suggest that backing can be null here, but we don't know how: rdar://problem/18545452.
ASSERT(backing);
if (!backing)
return 0;
ASSERT(treeState.parentNodeID || nodeType == ScrollingNodeType::Subframe);
ASSERT_IMPLIES(nodeType == ScrollingNodeType::MainFrame, !treeState.parentNodeID.value());
ScrollCoordinationRole role = scrollCoordinationRoleForNodeType(nodeType);
ScrollingNodeID nodeID = backing->scrollingNodeIDForRole(role);
nodeID = registerScrollingNodeID(*scrollingCoordinator, nodeID, nodeType, treeState);
LOG_WITH_STREAM(ScrollingTree, stream << "RenderLayerCompositor " << this << " attachScrollingNode " << nodeID << " (layer " << backing->graphicsLayer()->primaryLayerID() << ") type " << nodeType << " parent " << treeState.parentNodeID.value_or(0));
if (!nodeID)
return 0;
backing->setScrollingNodeIDForRole(nodeID, role);
#if ENABLE(SCROLLING_THREAD)
if (nodeType == ScrollingNodeType::Subframe)
m_clipLayer->setScrollingNodeID(nodeID);
#endif
m_scrollingNodeToLayerMap.add(nodeID, layer);
return nodeID;
}
ScrollingNodeID RenderLayerCompositor::registerScrollingNodeID(ScrollingCoordinator& scrollingCoordinator, ScrollingNodeID nodeID, ScrollingNodeType nodeType, struct ScrollingTreeState& treeState)
{
if (!nodeID)
nodeID = scrollingCoordinator.uniqueScrollingNodeID();
if (nodeType == ScrollingNodeType::Subframe && !treeState.parentNodeID)
nodeID = scrollingCoordinator.createNode(nodeType, nodeID);
else {
auto newNodeID = scrollingCoordinator.insertNode(nodeType, nodeID, treeState.parentNodeID.value_or(0), treeState.nextChildIndex);
if (newNodeID != nodeID) {
// We'll get a new nodeID if the type changed (and not if the node is new).
scrollingCoordinator.unparentChildrenAndDestroyNode(nodeID);
m_scrollingNodeToLayerMap.remove(nodeID);
}
nodeID = newNodeID;
}
ASSERT(nodeID);
if (!nodeID)
return 0;
++treeState.nextChildIndex;
return nodeID;
}
void RenderLayerCompositor::detachScrollCoordinatedLayerWithRole(RenderLayer& layer, ScrollingCoordinator& scrollingCoordinator, ScrollCoordinationRole role)
{
auto unregisterNode = [&](ScrollingNodeID nodeID) {
auto childNodes = scrollingCoordinator.childrenOfNode(nodeID);
for (auto childNodeID : childNodes) {
if (auto weakLayer = m_scrollingNodeToLayerMap.get(childNodeID))
weakLayer->setNeedsScrollingTreeUpdate();
}
m_scrollingNodeToLayerMap.remove(nodeID);
};
if (role == ScrollCoordinationRole::ScrollingProxy) {
ASSERT(layer.isComposited());
auto* clippingStack = layer.backing()->ancestorClippingStack();
if (!clippingStack)
return;
auto& stack = clippingStack->stack();
for (auto& entry : stack) {
if (entry.overflowScrollProxyNodeID)
unregisterNode(entry.overflowScrollProxyNodeID);
}
return;
}
auto nodeID = layer.backing()->scrollingNodeIDForRole(role);
if (!nodeID)
return;
unregisterNode(nodeID);
}
void RenderLayerCompositor::detachScrollCoordinatedLayer(RenderLayer& layer, OptionSet<ScrollCoordinationRole> roles)
{
auto* backing = layer.backing();
if (!backing)
return;
auto* scrollingCoordinator = this->scrollingCoordinator();
if (roles.contains(ScrollCoordinationRole::Scrolling))
detachScrollCoordinatedLayerWithRole(layer, *scrollingCoordinator, ScrollCoordinationRole::Scrolling);
if (roles.contains(ScrollCoordinationRole::ScrollingProxy))
detachScrollCoordinatedLayerWithRole(layer, *scrollingCoordinator, ScrollCoordinationRole::ScrollingProxy);
if (roles.contains(ScrollCoordinationRole::FrameHosting))
detachScrollCoordinatedLayerWithRole(layer, *scrollingCoordinator, ScrollCoordinationRole::FrameHosting);
if (roles.contains(ScrollCoordinationRole::ViewportConstrained))
detachScrollCoordinatedLayerWithRole(layer, *scrollingCoordinator, ScrollCoordinationRole::ViewportConstrained);
if (roles.contains(ScrollCoordinationRole::Positioning))
detachScrollCoordinatedLayerWithRole(layer, *scrollingCoordinator, ScrollCoordinationRole::Positioning);
backing->detachFromScrollingCoordinator(roles);
}
OptionSet<ScrollCoordinationRole> RenderLayerCompositor::coordinatedScrollingRolesForLayer(const RenderLayer& layer, const RenderLayer* compositingAncestor) const
{
OptionSet<ScrollCoordinationRole> coordinationRoles;
if (isViewportConstrainedFixedOrStickyLayer(layer))
coordinationRoles.add(ScrollCoordinationRole::ViewportConstrained);
if (useCoordinatedScrollingForLayer(layer))
coordinationRoles.add(ScrollCoordinationRole::Scrolling);
auto coordinatedPositioning = computeCoordinatedPositioningForLayer(layer, compositingAncestor);
switch (coordinatedPositioning) {
case ScrollPositioningBehavior::Moves:
coordinationRoles.add(ScrollCoordinationRole::ScrollingProxy);
break;
case ScrollPositioningBehavior::Stationary:
coordinationRoles.add(ScrollCoordinationRole::Positioning);
break;
case ScrollPositioningBehavior::None:
break;
}
if (isLayerForIFrameWithScrollCoordinatedContents(layer))
coordinationRoles.add(ScrollCoordinationRole::FrameHosting);
return coordinationRoles;
}
ScrollingNodeID RenderLayerCompositor::updateScrollCoordinationForLayer(RenderLayer& layer, const RenderLayer* compositingAncestor, ScrollingTreeState& treeState, OptionSet<ScrollingNodeChangeFlags> changes)
{
auto roles = coordinatedScrollingRolesForLayer(layer, compositingAncestor);
#if PLATFORM(IOS_FAMILY)
if (m_legacyScrollingLayerCoordinator) {
if (roles.contains(ScrollCoordinationRole::ViewportConstrained))
m_legacyScrollingLayerCoordinator->addViewportConstrainedLayer(layer);
else
m_legacyScrollingLayerCoordinator->removeViewportConstrainedLayer(layer);
}
#endif
if (!hasCoordinatedScrolling()) {
// If this frame isn't coordinated, it cannot contain any scrolling tree nodes.
return 0;
}
auto newNodeID = treeState.parentNodeID.value_or(0);
ScrollingTreeState childTreeState;
ScrollingTreeState* currentTreeState = &treeState;
// If there's a positioning node, it's the parent scrolling node for fixed/sticky/scrolling/frame hosting.
if (roles.contains(ScrollCoordinationRole::Positioning)) {
newNodeID = updateScrollingNodeForPositioningRole(layer, compositingAncestor, *currentTreeState, changes);
childTreeState.parentNodeID = newNodeID;
currentTreeState = &childTreeState;
} else
detachScrollCoordinatedLayer(layer, ScrollCoordinationRole::Positioning);
// If there's a scrolling proxy node, it's the parent scrolling node for fixed/sticky/scrolling/frame hosting.
if (roles.contains(ScrollCoordinationRole::ScrollingProxy)) {
newNodeID = updateScrollingNodeForScrollingProxyRole(layer, *currentTreeState, changes);
childTreeState.parentNodeID = newNodeID;
currentTreeState = &childTreeState;
} else
detachScrollCoordinatedLayer(layer, ScrollCoordinationRole::ScrollingProxy);
// If is fixed or sticky, it's the parent scrolling node for scrolling/frame hosting.
if (roles.contains(ScrollCoordinationRole::ViewportConstrained)) {
newNodeID = updateScrollingNodeForViewportConstrainedRole(layer, *currentTreeState, changes);
// ViewportConstrained nodes are the parent of same-layer scrolling nodes, so adjust the ScrollingTreeState.
childTreeState.parentNodeID = newNodeID;
currentTreeState = &childTreeState;
} else
detachScrollCoordinatedLayer(layer, ScrollCoordinationRole::ViewportConstrained);
if (roles.contains(ScrollCoordinationRole::Scrolling))
newNodeID = updateScrollingNodeForScrollingRole(layer, *currentTreeState, changes);
else
detachScrollCoordinatedLayer(layer, ScrollCoordinationRole::Scrolling);
if (roles.contains(ScrollCoordinationRole::FrameHosting))
newNodeID = updateScrollingNodeForFrameHostingRole(layer, *currentTreeState, changes);
else
detachScrollCoordinatedLayer(layer, ScrollCoordinationRole::FrameHosting);
return newNodeID;
}
ScrollingNodeID RenderLayerCompositor::updateScrollingNodeForViewportConstrainedRole(RenderLayer& layer, ScrollingTreeState& treeState, OptionSet<ScrollingNodeChangeFlags> changes)
{
auto* scrollingCoordinator = this->scrollingCoordinator();
auto nodeType = ScrollingNodeType::Fixed;
if (layer.renderer().style().position() == PositionType::Sticky)
nodeType = ScrollingNodeType::Sticky;
else
ASSERT(layer.renderer().isFixedPositioned());
auto newNodeID = attachScrollingNode(layer, nodeType, treeState);
if (!newNodeID) {
ASSERT_NOT_REACHED();
return treeState.parentNodeID.value_or(0);
}
LOG_WITH_STREAM(Compositing, stream << "Registering ViewportConstrained " << nodeType << " node " << newNodeID << " (layer " << layer.backing()->graphicsLayer()->primaryLayerID() << ") as child of " << treeState.parentNodeID.value_or(0));
if (changes & ScrollingNodeChangeFlags::Layer)
scrollingCoordinator->setNodeLayers(newNodeID, { layer.backing()->graphicsLayer() });
if (changes & ScrollingNodeChangeFlags::LayerGeometry) {
switch (nodeType) {
case ScrollingNodeType::Fixed:
scrollingCoordinator->setViewportConstraintedNodeConstraints(newNodeID, computeFixedViewportConstraints(layer));
break;
case ScrollingNodeType::Sticky:
scrollingCoordinator->setViewportConstraintedNodeConstraints(newNodeID, computeStickyViewportConstraints(layer));
break;
default:
break;
}
}
return newNodeID;
}
LayoutRect RenderLayerCompositor::parentRelativeScrollableRect(const RenderLayer& layer, const RenderLayer* ancestorLayer) const
{
// FIXME: ancestorLayer needs to be always non-null, so should become a reference.
if (!ancestorLayer) {
if (!layer.scrollableArea())
return LayoutRect();
return LayoutRect({ }, LayoutSize(layer.scrollableArea()->visibleSize()));
}
LayoutRect scrollableRect;
if (is<RenderBox>(layer.renderer()))
scrollableRect = downcast<RenderBox>(layer.renderer()).paddingBoxRect();
auto offset = layer.convertToLayerCoords(ancestorLayer, scrollableRect.location()); // FIXME: broken for columns.
scrollableRect.setLocation(offset);
return scrollableRect;
}
void RenderLayerCompositor::updateScrollingNodeLayers(ScrollingNodeID nodeID, RenderLayer& layer, ScrollingCoordinator& scrollingCoordinator)
{
if (layer.isRenderViewLayer()) {
FrameView& frameView = m_renderView.frameView();
scrollingCoordinator.setNodeLayers(nodeID, { nullptr,
scrollContainerLayer(), scrolledContentsLayer(),
fixedRootBackgroundLayer(), clipLayer(), rootContentsLayer(),
frameView.layerForHorizontalScrollbar(), frameView.layerForVerticalScrollbar() });
} else {
auto* scrollableArea = layer.scrollableArea();
ASSERT(scrollableArea);
auto& backing = *layer.backing();
scrollingCoordinator.setNodeLayers(nodeID, { backing.graphicsLayer(),
backing.scrollContainerLayer(), backing.scrolledContentsLayer(),
nullptr, nullptr, nullptr,
scrollableArea->layerForHorizontalScrollbar(), scrollableArea->layerForVerticalScrollbar() });
}
}
ScrollingNodeID RenderLayerCompositor::updateScrollingNodeForScrollingRole(RenderLayer& layer, ScrollingTreeState& treeState, OptionSet<ScrollingNodeChangeFlags> changes)
{
auto* scrollingCoordinator = this->scrollingCoordinator();
ScrollingNodeID newNodeID = 0;
if (layer.isRenderViewLayer()) {
FrameView& frameView = m_renderView.frameView();
ASSERT_UNUSED(frameView, scrollingCoordinator->coordinatesScrollingForFrameView(frameView));
newNodeID = attachScrollingNode(*m_renderView.layer(), m_renderView.frame().isMainFrame() ? ScrollingNodeType::MainFrame : ScrollingNodeType::Subframe, treeState);
if (!newNodeID) {
ASSERT_NOT_REACHED();
return treeState.parentNodeID.value_or(0);
}
if (changes & ScrollingNodeChangeFlags::Layer)
updateScrollingNodeLayers(newNodeID, layer, *scrollingCoordinator);
if (changes & ScrollingNodeChangeFlags::LayerGeometry) {
scrollingCoordinator->setScrollingNodeScrollableAreaGeometry(newNodeID, frameView);
scrollingCoordinator->setFrameScrollingNodeState(newNodeID, frameView);
}
} else {
newNodeID = attachScrollingNode(layer, ScrollingNodeType::Overflow, treeState);
if (!newNodeID) {
ASSERT_NOT_REACHED();
return treeState.parentNodeID.value_or(0);
}
if (changes & ScrollingNodeChangeFlags::Layer)
updateScrollingNodeLayers(newNodeID, layer, *scrollingCoordinator);
if (changes & ScrollingNodeChangeFlags::LayerGeometry && treeState.parentNodeID) {
if (auto* scrollableArea = layer.scrollableArea())
scrollingCoordinator->setScrollingNodeScrollableAreaGeometry(newNodeID, *scrollableArea);
}
}
return newNodeID;
}
ScrollingNodeID RenderLayerCompositor::updateScrollingNodeForScrollingProxyRole(RenderLayer& layer, ScrollingTreeState& treeState, OptionSet<ScrollingNodeChangeFlags> changes)
{
auto* scrollingCoordinator = this->scrollingCoordinator();
auto* clippingStack = layer.backing()->ancestorClippingStack();
if (!clippingStack) {
ASSERT_NOT_REACHED();
return treeState.parentNodeID.value_or(0);
}
ScrollingNodeID nodeID = 0;
for (auto& entry : clippingStack->stack()) {
if (!entry.clipData.isOverflowScroll)
continue;
nodeID = registerScrollingNodeID(*scrollingCoordinator, entry.overflowScrollProxyNodeID, ScrollingNodeType::OverflowProxy, treeState);
if (!nodeID) {
ASSERT_NOT_REACHED();
return treeState.parentNodeID.value_or(0);
}
entry.overflowScrollProxyNodeID = nodeID;
#if ENABLE(SCROLLING_THREAD)
if (entry.clippingLayer)
entry.clippingLayer->setScrollingNodeID(nodeID);
#endif
if (changes & ScrollingNodeChangeFlags::Layer)
scrollingCoordinator->setNodeLayers(entry.overflowScrollProxyNodeID, { entry.clippingLayer.get() });
if (changes & ScrollingNodeChangeFlags::LayerGeometry) {
ASSERT(entry.clipData.clippingLayer);
ASSERT(entry.clipData.clippingLayer->isComposited());
ScrollingNodeID overflowScrollNodeID = 0;
if (auto* backing = entry.clipData.clippingLayer->backing())
overflowScrollNodeID = backing->scrollingNodeIDForRole(ScrollCoordinationRole::Scrolling);
Vector<ScrollingNodeID> scrollingNodeIDs;
if (overflowScrollNodeID)
scrollingNodeIDs.append(overflowScrollNodeID);
scrollingCoordinator->setRelatedOverflowScrollingNodes(entry.overflowScrollProxyNodeID, WTFMove(scrollingNodeIDs));
}
}
// FIXME: also m_overflowControlsHostLayerAncestorClippingStack
if (!nodeID)
return treeState.parentNodeID.value_or(0);
return nodeID;
}
ScrollingNodeID RenderLayerCompositor::updateScrollingNodeForFrameHostingRole(RenderLayer& layer, ScrollingTreeState& treeState, OptionSet<ScrollingNodeChangeFlags> changes)
{
auto* scrollingCoordinator = this->scrollingCoordinator();
auto newNodeID = attachScrollingNode(layer, ScrollingNodeType::FrameHosting, treeState);
if (!newNodeID) {
ASSERT_NOT_REACHED();
return treeState.parentNodeID.value_or(0);
}
if (changes & ScrollingNodeChangeFlags::Layer)
scrollingCoordinator->setNodeLayers(newNodeID, { layer.backing()->graphicsLayer() });
return newNodeID;
}
ScrollingNodeID RenderLayerCompositor::updateScrollingNodeForPositioningRole(RenderLayer& layer, const RenderLayer* compositingAncestor, ScrollingTreeState& treeState, OptionSet<ScrollingNodeChangeFlags> changes)
{
auto* scrollingCoordinator = this->scrollingCoordinator();
auto newNodeID = attachScrollingNode(layer, ScrollingNodeType::Positioned, treeState);
if (!newNodeID) {
ASSERT_NOT_REACHED();
return treeState.parentNodeID.value_or(0);
}
if (changes & ScrollingNodeChangeFlags::Layer) {
auto& backing = *layer.backing();
scrollingCoordinator->setNodeLayers(newNodeID, { backing.graphicsLayer() });
}
if (changes & ScrollingNodeChangeFlags::LayerGeometry && treeState.parentNodeID) {
// Would be nice to avoid calling computeCoordinatedPositioningForLayer() again.
auto positioningBehavior = computeCoordinatedPositioningForLayer(layer, compositingAncestor);
auto relatedNodeIDs = collectRelatedCoordinatedScrollingNodes(layer, positioningBehavior);
scrollingCoordinator->setRelatedOverflowScrollingNodes(newNodeID, WTFMove(relatedNodeIDs));
auto* graphicsLayer = layer.backing()->graphicsLayer();
AbsolutePositionConstraints constraints;
constraints.setAlignmentOffset(graphicsLayer->pixelAlignmentOffset());
constraints.setLayerPositionAtLastLayout(graphicsLayer->position());
scrollingCoordinator->setPositionedNodeConstraints(newNodeID, constraints);
}
return newNodeID;
}
void RenderLayerCompositor::updateSynchronousScrollingNodes()
{
if (!hasCoordinatedScrolling())
return;
if (m_renderView.settings().fixedBackgroundsPaintRelativeToDocument())
return;
auto scrollingCoordinator = this->scrollingCoordinator();
ASSERT(scrollingCoordinator);
auto rootScrollingNodeID = m_renderView.frameView().scrollingNodeID();
HashSet<ScrollingNodeID> nodesToClear;
nodesToClear.reserveInitialCapacity(m_scrollingNodeToLayerMap.size());
for (auto key : m_scrollingNodeToLayerMap.keys())
nodesToClear.add(key);
auto clearSynchronousReasonsOnNonRootNodes = [&] {
for (auto nodeID : nodesToClear) {
if (nodeID == rootScrollingNodeID)
continue;
// Harmless to call setSynchronousScrollingReasons on a non-scrolling node.
scrollingCoordinator->setSynchronousScrollingReasons(nodeID, { });
}
};
auto setHasSlowRepaintObjectsSynchronousScrollingReasonOnRootNode = [&](bool hasSlowRepaintObjects) {
// ScrollingCoordinator manages all bits other than HasSlowRepaintObjects, so maintain their current value.
auto reasons = scrollingCoordinator->synchronousScrollingReasons(rootScrollingNodeID);
reasons.set({ SynchronousScrollingReason::HasSlowRepaintObjects }, hasSlowRepaintObjects);
scrollingCoordinator->setSynchronousScrollingReasons(rootScrollingNodeID, reasons);
};
auto slowRepaintObjects = m_renderView.frameView().slowRepaintObjects();
if (!slowRepaintObjects) {
setHasSlowRepaintObjectsSynchronousScrollingReasonOnRootNode(false);
clearSynchronousReasonsOnNonRootNodes();
return;
}
auto relevantScrollingScope = [](const RenderObject& renderer, const RenderLayer& layer) {
if (&layer.renderer() == &renderer)
return layer.boxScrollingScope();
return layer.contentsScrollingScope();
};
bool rootHasSlowRepaintObjects = false;
for (auto& renderer : *slowRepaintObjects) {
auto layer = renderer.enclosingLayer();
if (!layer)
continue;
auto scrollingScope = relevantScrollingScope(renderer, *layer);
if (!scrollingScope)
continue;
if (auto enclosingScrollingNodeID = asyncScrollableContainerNodeID(renderer)) {
LOG_WITH_STREAM(Scrolling, stream << "RenderLayerCompositor::updateSynchronousScrollingNodes - node " << enclosingScrollingNodeID << " slow-scrolling because of fixed backgrounds");
ASSERT(enclosingScrollingNodeID != rootScrollingNodeID);
scrollingCoordinator->setSynchronousScrollingReasons(enclosingScrollingNodeID, { SynchronousScrollingReason::HasSlowRepaintObjects });
nodesToClear.remove(enclosingScrollingNodeID);
// Although the root scrolling layer does not have a slow repaint object in it directly,
// we need to set some synchronous scrolling reason on it so that
// ScrollingCoordinator::shouldUpdateScrollLayerPositionSynchronously returns an
// appropriate value. (Scrolling itself would be correct without this, since the
// scrolling tree propagates DescendantScrollersHaveSynchronousScrolling bits up the
// tree, but shouldUpdateScrollLayerPositionSynchronously looks at the scrolling state
// tree instead.)
rootHasSlowRepaintObjects = true;
} else if (!layer->behavesAsFixed()) {
LOG_WITH_STREAM(Scrolling, stream << "RenderLayerCompositor::updateSynchronousScrollingNodes - root node slow-scrolling because of fixed backgrounds");
rootHasSlowRepaintObjects = true;
}
}
setHasSlowRepaintObjectsSynchronousScrollingReasonOnRootNode(rootHasSlowRepaintObjects);
clearSynchronousReasonsOnNonRootNodes();
}
ScrollableArea* RenderLayerCompositor::scrollableAreaForScrollingNodeID(ScrollingNodeID nodeID) const
{
if (!nodeID)
return nullptr;
if (nodeID == m_renderView.frameView().scrollingNodeID())
return &m_renderView.frameView();
return m_scrollingNodeToLayerMap.get(nodeID)->scrollableArea();
}
void RenderLayerCompositor::willRemoveScrollingLayerWithBacking(RenderLayer& layer, RenderLayerBacking& backing)
{
if (scrollingCoordinator())
return;
#if PLATFORM(IOS_FAMILY)
ASSERT(m_renderView.document().backForwardCacheState() == Document::NotInBackForwardCache);
if (m_legacyScrollingLayerCoordinator)
m_legacyScrollingLayerCoordinator->removeScrollingLayer(layer, backing);
#else
UNUSED_PARAM(layer);
UNUSED_PARAM(backing);
#endif
}
// FIXME: This should really be called from the updateBackingAndHierarchy.
void RenderLayerCompositor::didAddScrollingLayer(RenderLayer& layer)
{
if (scrollingCoordinator())
return;
#if PLATFORM(IOS_FAMILY)
ASSERT(m_renderView.document().backForwardCacheState() == Document::NotInBackForwardCache);
if (m_legacyScrollingLayerCoordinator)
m_legacyScrollingLayerCoordinator->addScrollingLayer(layer);
#else
UNUSED_PARAM(layer);
#endif
}
void RenderLayerCompositor::windowScreenDidChange(PlatformDisplayID displayID)
{
if (m_layerUpdater)
m_layerUpdater->screenDidChange(displayID);
}
ScrollingCoordinator* RenderLayerCompositor::scrollingCoordinator() const
{
return page().scrollingCoordinator();
}
GraphicsLayerFactory* RenderLayerCompositor::graphicsLayerFactory() const
{
return page().chrome().client().graphicsLayerFactory();
}
void RenderLayerCompositor::updateScrollSnapPropertiesWithFrameView(const FrameView& frameView) const
{
if (auto* coordinator = scrollingCoordinator())
coordinator->updateScrollSnapPropertiesWithFrameView(frameView);
}
Page& RenderLayerCompositor::page() const
{
return m_renderView.page();
}
TextStream& operator<<(TextStream& ts, CompositingUpdateType updateType)
{
switch (updateType) {
case CompositingUpdateType::AfterStyleChange: ts << "after style change"; break;
case CompositingUpdateType::AfterLayout: ts << "after layout"; break;
case CompositingUpdateType::OnScroll: ts << "on scroll"; break;
case CompositingUpdateType::OnCompositedScroll: ts << "on composited scroll"; break;
}
return ts;
}
TextStream& operator<<(TextStream& ts, CompositingPolicy compositingPolicy)
{
switch (compositingPolicy) {
case CompositingPolicy::Normal: ts << "normal"; break;
case CompositingPolicy::Conservative: ts << "conservative"; break;
}
return ts;
}
TextStream& operator<<(TextStream& ts, CompositingReason compositingReason)
{
return ts << compositingReasonToString(compositingReason);
}
#if PLATFORM(IOS_FAMILY)
typedef HashMap<PlatformLayer*, std::unique_ptr<ViewportConstraints>> LayerMap;
typedef HashMap<PlatformLayer*, PlatformLayer*> StickyContainerMap;
void LegacyWebKitScrollingLayerCoordinator::registerAllViewportConstrainedLayers(RenderLayerCompositor& compositor)
{
if (!m_coordinateViewportConstrainedLayers)
return;
LayerMap layerMap;
StickyContainerMap stickyContainerMap;
for (auto* layer : m_viewportConstrainedLayers) {
ASSERT(layer->isComposited());
std::unique_ptr<ViewportConstraints> constraints;
if (layer->renderer().isStickilyPositioned()) {
constraints = makeUnique<StickyPositionViewportConstraints>(compositor.computeStickyViewportConstraints(*layer));
const RenderLayer* enclosingTouchScrollableLayer = nullptr;
if (compositor.isAsyncScrollableStickyLayer(*layer, &enclosingTouchScrollableLayer) && enclosingTouchScrollableLayer) {
ASSERT(enclosingTouchScrollableLayer->isComposited());
// what
stickyContainerMap.add(layer->backing()->graphicsLayer()->platformLayer(), enclosingTouchScrollableLayer->backing()->scrollContainerLayer()->platformLayer());
}
} else if (layer->renderer().isFixedPositioned())
constraints = makeUnique<FixedPositionViewportConstraints>(compositor.computeFixedViewportConstraints(*layer));
else
continue;
layerMap.add(layer->backing()->graphicsLayer()->platformLayer(), WTFMove(constraints));
}
m_chromeClient.updateViewportConstrainedLayers(layerMap, stickyContainerMap);
}
void LegacyWebKitScrollingLayerCoordinator::unregisterAllViewportConstrainedLayers()
{
if (!m_coordinateViewportConstrainedLayers)
return;
LayerMap layerMap;
m_chromeClient.updateViewportConstrainedLayers(layerMap, { });
}
void LegacyWebKitScrollingLayerCoordinator::updateScrollingLayer(RenderLayer& layer)
{
auto* backing = layer.backing();
ASSERT(backing);
auto* scrollableArea = layer.scrollableArea();
ASSERT(scrollableArea);
bool allowHorizontalScrollbar = !scrollableArea->horizontalScrollbarHiddenByStyle();
bool allowVerticalScrollbar = !scrollableArea->verticalScrollbarHiddenByStyle();
m_chromeClient.addOrUpdateScrollingLayer(layer.renderer().element(), backing->scrollContainerLayer()->platformLayer(), backing->scrolledContentsLayer()->platformLayer(),
scrollableArea->reachableTotalContentsSize(), allowHorizontalScrollbar, allowVerticalScrollbar);
}
void LegacyWebKitScrollingLayerCoordinator::registerAllScrollingLayers()
{
for (auto* layer : m_scrollingLayers)
updateScrollingLayer(*layer);
}
void LegacyWebKitScrollingLayerCoordinator::unregisterAllScrollingLayers()
{
for (auto* layer : m_scrollingLayers) {
auto* backing = layer->backing();
ASSERT(backing);
m_chromeClient.removeScrollingLayer(layer->renderer().element(), backing->scrollContainerLayer()->platformLayer(), backing->scrolledContentsLayer()->platformLayer());
}
}
void LegacyWebKitScrollingLayerCoordinator::addScrollingLayer(RenderLayer& layer)
{
m_scrollingLayers.add(&layer);
}
void LegacyWebKitScrollingLayerCoordinator::removeScrollingLayer(RenderLayer& layer, RenderLayerBacking& backing)
{
if (m_scrollingLayers.remove(&layer)) {
auto* scrollContainerLayer = backing.scrollContainerLayer()->platformLayer();
auto* scrolledContentsLayer = backing.scrolledContentsLayer()->platformLayer();
m_chromeClient.removeScrollingLayer(layer.renderer().element(), scrollContainerLayer, scrolledContentsLayer);
}
}
void LegacyWebKitScrollingLayerCoordinator::removeLayer(RenderLayer& layer)
{
removeScrollingLayer(layer, *layer.backing());
// We'll put the new set of layers to the client via registerAllViewportConstrainedLayers() at flush time.
m_viewportConstrainedLayers.remove(&layer);
}
void LegacyWebKitScrollingLayerCoordinator::addViewportConstrainedLayer(RenderLayer& layer)
{
m_viewportConstrainedLayers.add(&layer);
}
void LegacyWebKitScrollingLayerCoordinator::removeViewportConstrainedLayer(RenderLayer& layer)
{
m_viewportConstrainedLayers.remove(&layer);
}
#endif
} // namespace WebCore
#if ENABLE(TREE_DEBUGGING)
void showGraphicsLayerTreeForCompositor(WebCore::RenderLayerCompositor& compositor)
{
showGraphicsLayerTree(compositor.rootGraphicsLayer());
}
#endif