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/*
* Copyright (C) 2009, 2013 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.
*/
#pragma once
#include "ChromeClient.h"
#include "GraphicsLayerClient.h"
#include "GraphicsLayerUpdater.h"
#include "RenderLayer.h"
#include <wtf/HashMap.h>
#include <wtf/OptionSet.h>
namespace WebCore {
class FixedPositionViewportConstraints;
class GraphicsLayer;
class GraphicsLayerUpdater;
class LayerOverlapMap;
class RenderEmbeddedObject;
class RenderVideo;
class RenderWidget;
class ScrollingCoordinator;
class StickyPositionViewportConstraints;
class TiledBacking;
typedef unsigned LayerTreeFlags;
enum class CompositingUpdateType {
AfterStyleChange,
AfterLayout,
OnScroll,
OnCompositedScroll
};
enum class CompositingReason {
Transform3D = 1 << 0,
Video = 1 << 1,
Canvas = 1 << 2,
Plugin = 1 << 3,
IFrame = 1 << 4,
BackfaceVisibilityHidden = 1 << 5,
ClipsCompositingDescendants = 1 << 6,
Animation = 1 << 7,
Filters = 1 << 8,
PositionFixed = 1 << 9,
PositionSticky = 1 << 10,
OverflowScrolling = 1 << 11,
Stacking = 1 << 12,
Overlap = 1 << 13,
OverflowScrollPositioning = 1 << 14,
NegativeZIndexChildren = 1 << 15,
TransformWithCompositedDescendants = 1 << 16,
OpacityWithCompositedDescendants = 1 << 17,
MaskWithCompositedDescendants = 1 << 18,
ReflectionWithCompositedDescendants = 1 << 19,
FilterWithCompositedDescendants = 1 << 20,
BlendingWithCompositedDescendants = 1 << 21,
Perspective = 1 << 22,
Preserve3D = 1 << 23,
WillChange = 1 << 24,
Root = 1 << 25,
IsolatesCompositedBlendingDescendants = 1 << 26,
EmbeddedView = 1 << 27,
};
enum class ScrollCoordinationRole {
ViewportConstrained = 1 << 0,
Scrolling = 1 << 1,
FrameHosting = 1 << 2,
Positioning = 1 << 3,
};
#if PLATFORM(IOS_FAMILY)
class LegacyWebKitScrollingLayerCoordinator {
public:
LegacyWebKitScrollingLayerCoordinator(ChromeClient& chromeClient, bool coordinateViewportConstrainedLayers)
: m_chromeClient(chromeClient)
, m_coordinateViewportConstrainedLayers(coordinateViewportConstrainedLayers)
{
}
void registerAllViewportConstrainedLayers(RenderLayerCompositor&);
void unregisterAllViewportConstrainedLayers();
void registerAllScrollingLayers();
void registerScrollingLayersNeedingUpdate();
void unregisterAllScrollingLayers();
void addScrollingLayer(RenderLayer&);
void removeScrollingLayer(RenderLayer&, RenderLayerBacking&);
void addViewportConstrainedLayer(RenderLayer&);
void removeViewportConstrainedLayer(RenderLayer&);
void didChangePlatformLayerForLayer(RenderLayer&);
void removeLayer(RenderLayer&);
private:
void updateScrollingLayer(RenderLayer&);
ChromeClient& m_chromeClient;
HashSet<RenderLayer*> m_scrollingLayers;
HashSet<RenderLayer*> m_viewportConstrainedLayers;
HashSet<RenderLayer*> m_scrollingLayersNeedingUpdate;
const bool m_coordinateViewportConstrainedLayers;
};
#endif
// RenderLayerCompositor manages the hierarchy of
// composited RenderLayers. It determines which RenderLayers
// become compositing, and creates and maintains a hierarchy of
// GraphicsLayers based on the RenderLayer painting order.
//
// There is one RenderLayerCompositor per RenderView.
class RenderLayerCompositor final : public GraphicsLayerClient, public GraphicsLayerUpdaterClient {
WTF_MAKE_FAST_ALLOCATED;
friend class LegacyWebKitScrollingLayerCoordinator;
public:
explicit RenderLayerCompositor(RenderView&);
virtual ~RenderLayerCompositor();
// Return true if this RenderView is in "compositing mode" (i.e. has one or more
// composited RenderLayers)
bool usesCompositing() const { return m_compositing; }
// This will make a compositing layer at the root automatically, and hook up to
// the native view/window system.
void enableCompositingMode(bool enable = true);
bool inForcedCompositingMode() const { return m_forceCompositingMode; }
// True when some content element other than the root is composited.
bool hasContentCompositingLayers() const { return m_contentLayersCount; }
// Returns true if the accelerated compositing is enabled
bool hasAcceleratedCompositing() const { return m_hasAcceleratedCompositing; }
bool canRender3DTransforms() const;
void willRecalcStyle();
// Returns true if the composited layers were actually updated.
bool didRecalcStyleWithNoPendingLayout();
// GraphicsLayers buffer state, which gets pushed to the underlying platform layers
// at specific times.
void scheduleLayerFlush(bool canThrottle = false);
void flushPendingLayerChanges(bool isFlushRoot = true);
// Called when the GraphicsLayer for the given RenderLayer has flushed changes inside of flushPendingLayerChanges().
void didChangePlatformLayerForLayer(RenderLayer&, const GraphicsLayer*);
// Called when something outside WebKit affects the visible rect (e.g. delegated scrolling). Might schedule a layer flush.
void didChangeVisibleRect();
// Rebuild the tree of compositing layers
bool updateCompositingLayers(CompositingUpdateType, RenderLayer* updateRoot = nullptr);
// This is only used when state changes and we do not exepect a style update or layout to happen soon (e.g. when
// we discover that an iframe is overlapped during painting).
void scheduleCompositingLayerUpdate();
// This is used to cancel any pending update timers when the document goes into page cache.
void cancelCompositingLayerUpdate();
// Update the compositing state of the given layer. Returns true if that state changed.
enum CompositingChangeRepaint { CompositingChangeRepaintNow, CompositingChangeWillRepaintLater };
enum class LayoutUpToDate {
Yes, No
};
struct RequiresCompositingData {
LayoutUpToDate layoutUpToDate { LayoutUpToDate::Yes };
RenderLayer::ViewportConstrainedNotCompositedReason nonCompositedForPositionReason { RenderLayer::NoNotCompositedReason };
bool reevaluateAfterLayout { false };
};
bool updateLayerCompositingState(RenderLayer&, RequiresCompositingData&, CompositingChangeRepaint = CompositingChangeRepaintNow);
// Whether layer's backing needs a graphics layer to do clipping by an ancestor (non-stacking-context parent with overflow).
bool clippedByAncestor(RenderLayer&) const;
// Whether layer's backing needs a graphics layer to clip z-order children of the given layer.
static bool clipsCompositingDescendants(const RenderLayer&);
// Whether the given layer needs an extra 'contents' layer.
bool needsContentsCompositingLayer(const RenderLayer&) const;
bool fixedLayerIntersectsViewport(const RenderLayer&) const;
bool supportsFixedRootBackgroundCompositing() const;
bool needsFixedRootBackgroundLayer(const RenderLayer&) const;
GraphicsLayer* fixedRootBackgroundLayer() const;
void rootOrBodyStyleChanged(RenderElement&, const RenderStyle* oldStyle);
// Called after the view transparency, or the document or base background color change.
void rootBackgroundColorOrTransparencyChanged();
// Repaint the appropriate layers when the given RenderLayer starts or stops being composited.
void repaintOnCompositingChange(RenderLayer&);
void repaintInCompositedAncestor(RenderLayer&, const LayoutRect&);
// Notify us that a layer has been added or removed
void layerWasAdded(RenderLayer& parent, RenderLayer& child);
void layerWillBeRemoved(RenderLayer& parent, RenderLayer& child);
void layerStyleChanged(StyleDifference, RenderLayer&, const RenderStyle* oldStyle);
static bool canCompositeClipPath(const RenderLayer&);
// Get the nearest ancestor layer that has overflow or clip, but is not a stacking context
RenderLayer* enclosingNonStackingClippingLayer(const RenderLayer&) const;
// Repaint all composited layers.
void repaintCompositedLayers();
// Returns true if the given layer needs it own backing store.
bool requiresOwnBackingStore(const RenderLayer&, const RenderLayer* compositingAncestorLayer, const LayoutRect& layerCompositedBoundsInAncestor, const LayoutRect& ancestorCompositedBounds) const;
WEBCORE_EXPORT RenderLayer& rootRenderLayer() const;
GraphicsLayer* rootGraphicsLayer() const;
GraphicsLayer* scrollContainerLayer() const { return m_scrollContainerLayer.get(); }
GraphicsLayer* scrolledContentsLayer() const { return m_scrolledContentsLayer.get(); }
GraphicsLayer* clipLayer() const { return m_clipLayer.get(); }
GraphicsLayer* rootContentsLayer() const { return m_rootContentsLayer.get(); }
GraphicsLayer* layerForClipping() const { return m_clipLayer ? m_clipLayer.get() : m_scrollContainerLayer.get(); }
#if ENABLE(RUBBER_BANDING)
GraphicsLayer* headerLayer() const { return m_layerForHeader.get(); }
GraphicsLayer* footerLayer() const { return m_layerForFooter.get(); }
#endif
enum RootLayerAttachment {
RootLayerUnattached,
RootLayerAttachedViaChromeClient,
RootLayerAttachedViaEnclosingFrame
};
RootLayerAttachment rootLayerAttachment() const { return m_rootLayerAttachment; }
void updateRootLayerAttachment();
void updateRootLayerPosition();
void setIsInWindow(bool);
void clearBackingForAllLayers();
void layerBecameComposited(const RenderLayer&);
void layerBecameNonComposited(const RenderLayer&);
#if ENABLE(VIDEO)
// Use by RenderVideo to ask if it should try to use accelerated compositing.
bool canAccelerateVideoRendering(RenderVideo&) const;
#endif
// Walk the tree looking for layers with 3d transforms. Useful in case you need
// to know if there is non-affine content, e.g. for drawing into an image.
bool has3DContent() const;
static RenderLayerCompositor* frameContentsCompositor(RenderWidget&);
// Return true if the layers changed.
bool parentFrameContentLayers(RenderWidget&);
// Update the geometry of the layers used for clipping and scrolling in frames.
void frameViewDidChangeLocation(const IntPoint& contentsOffset);
void frameViewDidChangeSize();
void frameViewDidScroll();
void frameViewDidAddOrRemoveScrollbars();
void frameViewDidLayout();
void rootLayerConfigurationChanged();
String layerTreeAsText(LayerTreeFlags);
float deviceScaleFactor() const override;
float contentsScaleMultiplierForNewTiles(const GraphicsLayer*) const override;
float pageScaleFactor() const override;
float zoomedOutPageScaleFactor() const override;
void didChangePlatformLayerForLayer(const GraphicsLayer*) override { }
void notifyFlushBeforeDisplayRefresh(const GraphicsLayer*) override;
void layerTiledBackingUsageChanged(const GraphicsLayer*, bool /*usingTiledBacking*/);
bool acceleratedDrawingEnabled() const { return m_acceleratedDrawingEnabled; }
bool displayListDrawingEnabled() const { return m_displayListDrawingEnabled; }
void deviceOrPageScaleFactorChanged();
void windowScreenDidChange(PlatformDisplayID);
GraphicsLayer* layerForHorizontalScrollbar() const { return m_layerForHorizontalScrollbar.get(); }
GraphicsLayer* layerForVerticalScrollbar() const { return m_layerForVerticalScrollbar.get(); }
GraphicsLayer* layerForScrollCorner() const { return m_layerForScrollCorner.get(); }
#if ENABLE(RUBBER_BANDING)
GraphicsLayer* layerForOverhangAreas() const { return m_layerForOverhangAreas.get(); }
GraphicsLayer* layerForContentShadow() const { return m_contentShadowLayer.get(); }
GraphicsLayer* updateLayerForTopOverhangArea(bool wantsLayer);
GraphicsLayer* updateLayerForBottomOverhangArea(bool wantsLayer);
GraphicsLayer* updateLayerForHeader(bool wantsLayer);
GraphicsLayer* updateLayerForFooter(bool wantsLayer);
#endif
// FIXME: make the coordinated/async terminology consistent.
bool isViewportConstrainedFixedOrStickyLayer(const RenderLayer&) const;
bool useCoordinatedScrollingForLayer(const RenderLayer&) const;
ScrollPositioningBehavior computeCoordinatedPositioningForLayer(const RenderLayer&) const;
bool isLayerForIFrameWithScrollCoordinatedContents(const RenderLayer&) const;
ScrollableArea* scrollableAreaForScrollLayerID(ScrollingNodeID) const;
void removeFromScrollCoordinatedLayers(RenderLayer&);
void willRemoveScrollingLayerWithBacking(RenderLayer&, RenderLayerBacking&);
void didAddScrollingLayer(RenderLayer&);
void resetTrackedRepaintRects();
void setTracksRepaints(bool tracksRepaints) { m_isTrackingRepaints = tracksRepaints; }
bool viewHasTransparentBackground(Color* backgroundColor = nullptr) const;
bool hasNonMainLayersWithTiledBacking() const { return m_layersWithTiledBackingCount; }
OptionSet<CompositingReason> reasonsForCompositing(const RenderLayer&) const;
void setLayerFlushThrottlingEnabled(bool);
void disableLayerFlushThrottlingTemporarilyForInteraction();
void didPaintBacking(RenderLayerBacking*);
const Color& rootExtendedBackgroundColor() const { return m_rootExtendedBackgroundColor; }
void updateRootContentLayerClipping();
#if ENABLE(CSS_SCROLL_SNAP)
void updateScrollSnapPropertiesWithFrameView(const FrameView&) const;
#endif
// For testing.
void startTrackingLayerFlushes() { m_layerFlushCount = 0; }
unsigned layerFlushCount() const { return m_layerFlushCount; }
void startTrackingCompositingUpdates() { m_compositingUpdateCount = 0; }
unsigned compositingUpdateCount() const { return m_compositingUpdateCount; }
private:
class BackingSharingState;
struct CompositingState;
struct OverlapExtent;
// Returns true if the policy changed.
bool updateCompositingPolicy();
// GraphicsLayerClient implementation
void notifyFlushRequired(const GraphicsLayer*) override;
void paintContents(const GraphicsLayer*, GraphicsContext&, GraphicsLayerPaintingPhase, const FloatRect&, GraphicsLayerPaintBehavior) override;
void customPositionForVisibleRectComputation(const GraphicsLayer*, FloatPoint&) const override;
bool isTrackingRepaints() const override { return m_isTrackingRepaints; }
// GraphicsLayerUpdaterClient implementation
void flushLayersSoon(GraphicsLayerUpdater&) override;
// Copy the accelerated compositing related flags from Settings
void cacheAcceleratedCompositingFlags();
void cacheAcceleratedCompositingFlagsAfterLayout();
// Whether the given RL needs a compositing layer.
bool needsToBeComposited(const RenderLayer&, RequiresCompositingData&) const;
// Whether the layer has an intrinsic need for compositing layer.
bool requiresCompositingLayer(const RenderLayer&, RequiresCompositingData&) const;
// Whether the layer could ever be composited.
bool canBeComposited(const RenderLayer&) const;
bool needsCompositingUpdateForStyleChangeOnNonCompositedLayer(RenderLayer&, const RenderStyle* oldStyle) const;
// Make or destroy the backing for this layer; returns true if backing changed.
enum class BackingRequired { No, Yes, Unknown };
bool updateBacking(RenderLayer&, RequiresCompositingData&, CompositingChangeRepaint shouldRepaint, BackingRequired = BackingRequired::Unknown);
void clearBackingForLayerIncludingDescendants(RenderLayer&);
// Repaint this and its child layers.
void recursiveRepaintLayer(RenderLayer&);
void computeExtent(const LayerOverlapMap&, const RenderLayer&, OverlapExtent&) const;
void addToOverlapMap(LayerOverlapMap&, const RenderLayer&, OverlapExtent&) const;
void addDescendantsToOverlapMapRecursive(LayerOverlapMap&, const RenderLayer&, const RenderLayer* ancestorLayer = nullptr) const;
void updateOverlapMap(LayerOverlapMap&, const RenderLayer&, OverlapExtent&, bool layerContributesToOverlap, bool addDescendantsToOverlap = false) const;
void updateCompositingLayersTimerFired();
void computeCompositingRequirements(RenderLayer* ancestorLayer, RenderLayer&, LayerOverlapMap&, CompositingState&, BackingSharingState&, bool& descendantHas3DTransform);
void traverseUnchangedSubtree(RenderLayer* ancestorLayer, RenderLayer&, LayerOverlapMap&, CompositingState&, BackingSharingState&, bool& descendantHas3DTransform);
enum class UpdateLevel {
AllDescendants = 1 << 0,
CompositedChildren = 1 << 1,
};
// Recurses down the tree, parenting descendant compositing layers and collecting an array of child layers for the current compositing layer.
void updateBackingAndHierarchy(RenderLayer&, Vector<Ref<GraphicsLayer>>& childGraphicsLayersOfEnclosingLayer, struct ScrollingTreeState&, OptionSet<UpdateLevel> = { }, int depth = 0);
bool layerHas3DContent(const RenderLayer&) const;
bool isRunningTransformAnimation(RenderLayerModelObject&) const;
void appendDocumentOverlayLayers(Vector<Ref<GraphicsLayer>>&);
bool needsCompositingForContentOrOverlays() const;
void ensureRootLayer();
void destroyRootLayer();
void attachRootLayer(RootLayerAttachment);
void detachRootLayer();
void rootLayerAttachmentChanged();
void updateOverflowControlsLayers();
void updateScrollLayerPosition();
void updateScrollLayerClipping();
FloatPoint positionForClipLayer() const;
void notifyIFramesOfCompositingChange();
#if PLATFORM(IOS_FAMILY)
void updateScrollCoordinatedLayersAfterFlushIncludingSubframes();
void updateScrollCoordinatedLayersAfterFlush();
#endif
FloatRect visibleRectForLayerFlushing() const;
Page& page() const;
GraphicsLayerFactory* graphicsLayerFactory() const;
ScrollingCoordinator* scrollingCoordinator() const;
#if USE(REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR)
RefPtr<DisplayRefreshMonitor> createDisplayRefreshMonitor(PlatformDisplayID) const override;
#endif
// Non layout-dependent
bool requiresCompositingForAnimation(RenderLayerModelObject&) const;
bool requiresCompositingForTransform(RenderLayerModelObject&) const;
bool requiresCompositingForBackfaceVisibility(RenderLayerModelObject&) const;
bool requiresCompositingForVideo(RenderLayerModelObject&) const;
bool requiresCompositingForCanvas(RenderLayerModelObject&) const;
bool requiresCompositingForFilters(RenderLayerModelObject&) const;
bool requiresCompositingForWillChange(RenderLayerModelObject&) const;
// Layout-dependent
bool requiresCompositingForPlugin(RenderLayerModelObject&, RequiresCompositingData&) const;
bool requiresCompositingForFrame(RenderLayerModelObject&, RequiresCompositingData&) const;
bool requiresCompositingForScrollableFrame(RequiresCompositingData&) const;
bool requiresCompositingForPosition(RenderLayerModelObject&, const RenderLayer&, RequiresCompositingData&) const;
bool requiresCompositingForOverflowScrolling(const RenderLayer&, RequiresCompositingData&) const;
bool requiresCompositingForEditableImage(RenderLayerModelObject&) const;
bool requiresCompositingForIndirectReason(const RenderLayer&, const RenderLayer* compositingAncestor, bool hasCompositedDescendants, bool has3DTransformedDescendants, bool paintsIntoProvidedBacking, RenderLayer::IndirectCompositingReason&) const;
static bool layerContainingBlockCrossesCoordinatedScrollingBoundary(const RenderLayer&, const RenderLayer& compositedAncestor);
static bool styleChangeMayAffectIndirectCompositingReasons(const RenderStyle& oldStyle, const RenderStyle& newStyle);
enum class ScrollingNodeChangeFlags {
Layer = 1 << 0,
LayerGeometry = 1 << 1,
};
ScrollingNodeID attachScrollingNode(RenderLayer&, ScrollingNodeType, struct ScrollingTreeState&);
// Returns the ScrollingNodeID which acts as the parent for children.
ScrollingNodeID updateScrollCoordinationForLayer(RenderLayer&, struct ScrollingTreeState&, OptionSet<ScrollCoordinationRole>, OptionSet<ScrollingNodeChangeFlags>);
// These return the ScrollingNodeID which acts as the parent for children.
ScrollingNodeID updateScrollingNodeForViewportConstrainedRole(RenderLayer&, struct ScrollingTreeState&, OptionSet<ScrollingNodeChangeFlags>);
ScrollingNodeID updateScrollingNodeForScrollingRole(RenderLayer&, struct ScrollingTreeState&, OptionSet<ScrollingNodeChangeFlags>);
ScrollingNodeID updateScrollingNodeForFrameHostingRole(RenderLayer&, struct ScrollingTreeState&, OptionSet<ScrollingNodeChangeFlags>);
ScrollingNodeID updateScrollingNodeForPositioningRole(RenderLayer&, struct ScrollingTreeState&, OptionSet<ScrollingNodeChangeFlags>);
void updateScrollingNodeLayers(ScrollingNodeID, RenderLayer&, ScrollingCoordinator&);
void detachScrollCoordinatedLayer(RenderLayer&, OptionSet<ScrollCoordinationRole>);
void detachScrollCoordinatedLayerWithRole(RenderLayer&, ScrollingCoordinator&, ScrollCoordinationRole);
FixedPositionViewportConstraints computeFixedViewportConstraints(RenderLayer&) const;
StickyPositionViewportConstraints computeStickyViewportConstraints(RenderLayer&) const;
LayoutRect rootParentRelativeScrollableRect() const;
LayoutRect parentRelativeScrollableRect(const RenderLayer&, const RenderLayer* ancestorLayer) const;
bool requiresScrollLayer(RootLayerAttachment) const;
bool requiresHorizontalScrollbarLayer() const;
bool requiresVerticalScrollbarLayer() const;
bool requiresScrollCornerLayer() const;
#if ENABLE(RUBBER_BANDING)
bool requiresOverhangAreasLayer() const;
bool requiresContentShadowLayer() const;
#endif
// True if the FrameView uses a ScrollingCoordinator.
bool hasCoordinatedScrolling() const;
// FIXME: make the coordinated/async terminology consistent.
bool isAsyncScrollableStickyLayer(const RenderLayer&, const RenderLayer** enclosingAcceleratedOverflowLayer = nullptr) const;
bool shouldCompositeOverflowControls() const;
bool isThrottlingLayerFlushes() const;
void startInitialLayerFlushTimerIfNeeded();
void startLayerFlushTimerIfNeeded();
void layerFlushTimerFired();
#if !LOG_DISABLED
const char* logReasonsForCompositing(const RenderLayer&);
void logLayerInfo(const RenderLayer&, const char*, int depth);
#endif
bool documentUsesTiledBacking() const;
bool isMainFrameCompositor() const;
private:
RenderView& m_renderView;
Timer m_updateCompositingLayersTimer;
ChromeClient::CompositingTriggerFlags m_compositingTriggers { static_cast<ChromeClient::CompositingTriggerFlags>(ChromeClient::AllTriggers) };
bool m_hasAcceleratedCompositing { true };
CompositingPolicy m_compositingPolicy { CompositingPolicy::Normal };
bool m_showDebugBorders { false };
bool m_showRepaintCounter { false };
bool m_acceleratedDrawingEnabled { false };
bool m_displayListDrawingEnabled { false };
bool m_compositing { false };
bool m_flushingLayers { false };
bool m_shouldFlushOnReattach { false };
bool m_forceCompositingMode { false };
bool m_inPostLayoutUpdate { false }; // true when it's OK to trust layout information (e.g. layer sizes and positions)
bool m_isTrackingRepaints { false }; // Used for testing.
unsigned m_contentLayersCount { 0 };
unsigned m_layersWithTiledBackingCount { 0 };
unsigned m_layerFlushCount { 0 };
unsigned m_compositingUpdateCount { 0 };
RootLayerAttachment m_rootLayerAttachment { RootLayerUnattached };
RefPtr<GraphicsLayer> m_rootContentsLayer;
// Enclosing clipping layer for iframe content
RefPtr<GraphicsLayer> m_clipLayer;
RefPtr<GraphicsLayer> m_scrollContainerLayer;
RefPtr<GraphicsLayer> m_scrolledContentsLayer;
// Enclosing layer for overflow controls and the clipping layer
RefPtr<GraphicsLayer> m_overflowControlsHostLayer;
// Layers for overflow controls
RefPtr<GraphicsLayer> m_layerForHorizontalScrollbar;
RefPtr<GraphicsLayer> m_layerForVerticalScrollbar;
RefPtr<GraphicsLayer> m_layerForScrollCorner;
#if ENABLE(RUBBER_BANDING)
RefPtr<GraphicsLayer> m_layerForOverhangAreas;
RefPtr<GraphicsLayer> m_contentShadowLayer;
RefPtr<GraphicsLayer> m_layerForTopOverhangArea;
RefPtr<GraphicsLayer> m_layerForBottomOverhangArea;
RefPtr<GraphicsLayer> m_layerForHeader;
RefPtr<GraphicsLayer> m_layerForFooter;
#endif
std::unique_ptr<GraphicsLayerUpdater> m_layerUpdater; // Updates tiled layer visible area periodically while animations are running.
Timer m_layerFlushTimer;
bool m_layerFlushThrottlingEnabled { false };
bool m_layerFlushThrottlingTemporarilyDisabledForInteraction { false };
bool m_hasPendingLayerFlush { false };
bool m_viewBackgroundIsTransparent { false };
#if !LOG_DISABLED
int m_rootLayerUpdateCount { 0 };
int m_obligateCompositedLayerCount { 0 }; // count of layer that have to be composited.
int m_secondaryCompositedLayerCount { 0 }; // count of layers that have to be composited because of stacking or overlap.
double m_obligatoryBackingStoreBytes { 0 };
double m_secondaryBackingStoreBytes { 0 };
#endif
Color m_viewBackgroundColor;
Color m_rootExtendedBackgroundColor;
HashMap<ScrollingNodeID, RenderLayer*> m_scrollingNodeToLayerMap;
#if PLATFORM(IOS_FAMILY)
std::unique_ptr<LegacyWebKitScrollingLayerCoordinator> m_legacyScrollingLayerCoordinator;
#endif
};
void paintScrollbar(Scrollbar*, GraphicsContext&, const IntRect& clip);
WTF::TextStream& operator<<(WTF::TextStream&, CompositingUpdateType);
WTF::TextStream& operator<<(WTF::TextStream&, CompositingPolicy);
} // namespace WebCore
#if ENABLE(TREE_DEBUGGING)
// Outside the WebCore namespace for ease of invocation from the debugger.
void showGraphicsLayerTreeForCompositor(WebCore::RenderLayerCompositor&);
#endif