src/cc/trees/layer_tree_host_impl.h

   1 // Copyright 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CC_TREES_LAYER_TREE_HOST_IMPL_H_
   6 #define CC_TREES_LAYER_TREE_HOST_IMPL_H_
   7
   8 #include <list>
   9 #include <set>
  10 #include <string>
  11 #include <vector>
  12
  13 #include "base/basictypes.h"
  14 #include "base/containers/hash_tables.h"
  15 #include "base/memory/scoped_ptr.h"
  16 #include "base/time/time.h"
  17 #include "cc/animation/animation_events.h"
  18 #include "cc/animation/animation_registrar.h"
  19 #include "cc/base/cc_export.h"
  20 #include "cc/debug/micro_benchmark_controller_impl.h"
  21 #include "cc/input/input_handler.h"
  22 #include "cc/input/layer_scroll_offset_delegate.h"
  23 #include "cc/input/top_controls_manager_client.h"
  24 #include "cc/layers/layer_lists.h"
  25 #include "cc/layers/render_pass_sink.h"
  26 #include "cc/output/begin_frame_args.h"
  27 #include "cc/output/managed_memory_policy.h"
  28 #include "cc/output/output_surface_client.h"
  29 #include "cc/output/renderer.h"
  30 #include "cc/quads/render_pass.h"
  31 #include "cc/resources/resource_provider.h"
  32 #include "cc/resources/tile_manager.h"
  33 #include "cc/scheduler/draw_swap_readback_result.h"
  34 #include "skia/ext/refptr.h"
  35 #include "third_party/skia/include/core/SkColor.h"
  36 #include "ui/gfx/rect.h"
  37
  38 namespace cc {
  39
  40 class CompletionEvent;
  41 class CompositorFrameMetadata;
  42 class DebugRectHistory;
  43 class FrameRateCounter;
  44 class LayerImpl;
  45 class LayerTreeHostImplTimeSourceAdapter;
  46 class LayerTreeImpl;
  47 class PageScaleAnimation;
  48 class PaintTimeCounter;
  49 class MemoryHistory;
  50 class RenderingStatsInstrumentation;
  51 class RenderPassDrawQuad;
  52 class ScrollbarLayerImplBase;
  53 class TextureMailboxDeleter;
  54 class TopControlsManager;
  55 class UIResourceBitmap;
  56 class UIResourceRequest;
  57 struct RendererCapabilitiesImpl;
  58
  59 // LayerTreeHost->Proxy callback interface.
  60 class LayerTreeHostImplClient {
  61  public:
  62   virtual void UpdateRendererCapabilitiesOnImplThread() = 0;
  63   virtual void DidLoseOutputSurfaceOnImplThread() = 0;
  64   virtual void DidSwapBuffersOnImplThread() = 0;
  65   virtual void OnSwapBuffersCompleteOnImplThread() = 0;
  66   virtual void BeginImplFrame(const BeginFrameArgs& args) = 0;
  67   virtual void OnCanDrawStateChanged(bool can_draw) = 0;
  68   virtual void NotifyReadyToActivate() = 0;
  69   // Please call these 2 functions through
  70   // LayerTreeHostImpl's SetNeedsRedraw() and SetNeedsRedrawRect().
  71   virtual void SetNeedsRedrawOnImplThread() = 0;
  72   virtual void SetNeedsRedrawRectOnImplThread(const gfx::Rect& damage_rect) = 0;
  73   virtual void DidInitializeVisibleTileOnImplThread() = 0;
  74   virtual void SetNeedsCommitOnImplThread() = 0;
  75   virtual void SetNeedsManageTilesOnImplThread() = 0;
  76   virtual void PostAnimationEventsToMainThreadOnImplThread(
  77       scoped_ptr<AnimationEventsVector> events) = 0;
  78   // Returns true if resources were deleted by this call.
  79   virtual bool ReduceContentsTextureMemoryOnImplThread(
  80       size_t limit_bytes,
  81       int priority_cutoff) = 0;
  82   virtual void SendManagedMemoryStats() = 0;
  83   virtual bool IsInsideDraw() = 0;
  84   virtual void RenewTreePriority() = 0;
  85   virtual void RequestScrollbarAnimationOnImplThread(base::TimeDelta delay) = 0;
  86   virtual void DidActivatePendingTree() = 0;
  87   virtual void DidManageTiles() = 0;
  88
  89  protected:
  90   virtual ~LayerTreeHostImplClient() {}
  91 };
  92
  93 // LayerTreeHostImpl owns the LayerImpl trees as well as associated rendering
  94 // state.
  95 class CC_EXPORT LayerTreeHostImpl
  96     : public InputHandler,
  97       public RendererClient,
  98       public TileManagerClient,
  99       public OutputSurfaceClient,
 100       public TopControlsManagerClient,
 101       public base::SupportsWeakPtr<LayerTreeHostImpl> {
 102  public:
 103   static scoped_ptr<LayerTreeHostImpl> Create(
 104       const LayerTreeSettings& settings,
 105       LayerTreeHostImplClient* client,
 106       Proxy* proxy,
 107       RenderingStatsInstrumentation* rendering_stats_instrumentation,
 108       SharedBitmapManager* manager,
 109       int id);
 110   virtual ~LayerTreeHostImpl();
 111
 112   // InputHandler implementation
 113   virtual void BindToClient(InputHandlerClient* client) OVERRIDE;
 114   virtual InputHandler::ScrollStatus ScrollBegin(
 115       const gfx::Point& viewport_point,
 116       InputHandler::ScrollInputType type) OVERRIDE;
 117   virtual bool ScrollBy(const gfx::Point& viewport_point,
 118                         const gfx::Vector2dF& scroll_delta) OVERRIDE;
 119   virtual bool ScrollVerticallyByPage(const gfx::Point& viewport_point,
 120                                       ScrollDirection direction) OVERRIDE;
 121   virtual void SetRootLayerScrollOffsetDelegate(
 122       LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate) OVERRIDE;
 123   virtual void OnRootLayerDelegatedScrollOffsetChanged() OVERRIDE;
 124   virtual void ScrollEnd() OVERRIDE;
 125   virtual InputHandler::ScrollStatus FlingScrollBegin() OVERRIDE;
 126   virtual void NotifyCurrentFlingVelocity(
 127       const gfx::Vector2dF& velocity) OVERRIDE;
 128   virtual void MouseMoveAt(const gfx::Point& viewport_point) OVERRIDE;
 129   virtual void PinchGestureBegin() OVERRIDE;
 130   virtual void PinchGestureUpdate(float magnify_delta,
 131                                   const gfx::Point& anchor) OVERRIDE;
 132   virtual void PinchGestureEnd() OVERRIDE;
 133   virtual void StartPageScaleAnimation(const gfx::Vector2d& target_offset,
 134                                        bool anchor_point,
 135                                        float page_scale,
 136                                        base::TimeDelta duration) OVERRIDE;
 137   virtual void ScheduleAnimation() OVERRIDE;
 138   virtual bool HaveTouchEventHandlersAt(const gfx::Point& viewport_port)
 139       OVERRIDE;
 140   virtual scoped_ptr<SwapPromiseMonitor> CreateLatencyInfoSwapPromiseMonitor(
 141       ui::LatencyInfo* latency) OVERRIDE;
 142
 143   // TopControlsManagerClient implementation.
 144   virtual void DidChangeTopControlsPosition() OVERRIDE;
 145   virtual bool HaveRootScrollLayer() const OVERRIDE;
 146
 147   void StartScrollbarAnimation();
 148
 149   struct CC_EXPORT FrameData : public RenderPassSink {
 150     FrameData();
 151     virtual ~FrameData();
 152     scoped_ptr<base::Value> AsValue() const;
 153
 154     std::vector<gfx::Rect> occluding_screen_space_rects;
 155     std::vector<gfx::Rect> non_occluding_screen_space_rects;
 156     RenderPassList render_passes;
 157     RenderPassIdHashMap render_passes_by_id;
 158     const LayerImplList* render_surface_layer_list;
 159     LayerImplList will_draw_layers;
 160     bool contains_incomplete_tile;
 161     bool has_no_damage;
 162
 163     // RenderPassSink implementation.
 164     virtual void AppendRenderPass(scoped_ptr<RenderPass> render_pass) OVERRIDE;
 165   };
 166
 167   virtual void BeginMainFrameAborted(bool did_handle);
 168   virtual void BeginCommit();
 169   virtual void CommitComplete();
 170   virtual void Animate(base::TimeTicks monotonic_time);
 171   virtual void UpdateAnimationState(bool start_ready_animations);
 172   void MainThreadHasStoppedFlinging();
 173   void UpdateBackgroundAnimateTicking(bool should_background_tick);
 174   void DidAnimateScrollOffset();
 175   void SetViewportDamage(const gfx::Rect& damage_rect);
 176
 177   virtual void ManageTiles();
 178
 179   // Returns false if problems occured preparing the frame, and we should try
 180   // to avoid displaying the frame. If PrepareToDraw is called, DidDrawAllLayers
 181   // must also be called, regardless of whether DrawLayers is called between the
 182   // two.
 183   virtual DrawSwapReadbackResult::DrawResult PrepareToDraw(
 184       FrameData* frame,
 185       const gfx::Rect& damage_rect);
 186   virtual void DrawLayers(FrameData* frame, base::TimeTicks frame_begin_time);
 187   // Must be called if and only if PrepareToDraw was called.
 188   void DidDrawAllLayers(const FrameData& frame);
 189
 190   const LayerTreeSettings& settings() const { return settings_; }
 191
 192   // Evict all textures by enforcing a memory policy with an allocation of 0.
 193   void EvictTexturesForTesting();
 194
 195   // When blocking, this prevents client_->NotifyReadyToActivate() from being
 196   // called. When disabled, it calls client_->NotifyReadyToActivate()
 197   // immediately if any notifications had been blocked while blocking.
 198   virtual void BlockNotifyReadyToActivateForTesting(bool block);
 199
 200   // This allows us to inject DidInitializeVisibleTile events for testing.
 201   void DidInitializeVisibleTileForTesting();
 202
 203   bool device_viewport_valid_for_tile_management() const {
 204     return device_viewport_valid_for_tile_management_;
 205   }
 206
 207   // Viewport size in draw space: this size is in physical pixels and is used
 208   // for draw properties, tilings, quads and render passes.
 209   gfx::Size DrawViewportSize() const;
 210
 211   // Viewport size for scrolling and fixed-position compensation. This value
 212   // excludes the URL bar and non-overlay scrollbars and is in DIP (and
 213   // invariant relative to page scale).
 214   gfx::SizeF UnscaledScrollableViewportSize() const;
 215   float VerticalAdjust() const;
 216
 217   // RendererClient implementation.
 218   virtual void SetFullRootLayerDamage() OVERRIDE;
 219
 220   // TileManagerClient implementation.
 221   virtual void NotifyReadyToActivate() OVERRIDE;
 222
 223   // OutputSurfaceClient implementation.
 224   virtual bool DeferredInitialize(
 225       scoped_refptr<ContextProvider> offscreen_context_provider) OVERRIDE;
 226   virtual void ReleaseGL() OVERRIDE;
 227   virtual void SetNeedsRedrawRect(const gfx::Rect& rect) OVERRIDE;
 228   virtual void BeginImplFrame(const BeginFrameArgs& args) OVERRIDE;
 229   virtual void SetExternalDrawConstraints(
 230       const gfx::Transform& transform,
 231       const gfx::Rect& viewport,
 232       const gfx::Rect& clip,
 233       bool valid_for_tile_management) OVERRIDE;
 234   virtual void DidLoseOutputSurface() OVERRIDE;
 235   virtual void DidSwapBuffers() OVERRIDE;
 236   virtual void OnSwapBuffersComplete() OVERRIDE;
 237   virtual void ReclaimResources(const CompositorFrameAck* ack) OVERRIDE;
 238   virtual void SetMemoryPolicy(const ManagedMemoryPolicy& policy) OVERRIDE;
 239   virtual void SetTreeActivationCallback(const base::Closure& callback)
 240       OVERRIDE;
 241
 242   // Called from LayerTreeImpl.
 243   void OnCanDrawStateChangedForTree();
 244
 245   // Implementation.
 246   bool CanDraw() const;
 247   OutputSurface* output_surface() const { return output_surface_.get(); }
 248
 249   void SetOffscreenContextProvider(
 250       const scoped_refptr<ContextProvider>& offscreen_context_provider);
 251   ContextProvider* offscreen_context_provider() const {
 252     return offscreen_context_provider_.get();
 253   }
 254
 255   std::string LayerTreeAsJson() const;
 256
 257   void FinishAllRendering();
 258   int SourceAnimationFrameNumber() const;
 259
 260   virtual bool InitializeRenderer(scoped_ptr<OutputSurface> output_surface);
 261   bool IsContextLost();
 262   TileManager* tile_manager() { return tile_manager_.get(); }
 263   Renderer* renderer() { return renderer_.get(); }
 264   const RendererCapabilitiesImpl& GetRendererCapabilities() const;
 265
 266   virtual bool SwapBuffers(const FrameData& frame);
 267   void SetNeedsBeginImplFrame(bool enable);
 268   void DidModifyTilePriorities();
 269
 270   void Readback(void* pixels, const gfx::Rect& rect_in_device_viewport);
 271
 272   LayerTreeImpl* active_tree() { return active_tree_.get(); }
 273   const LayerTreeImpl* active_tree() const { return active_tree_.get(); }
 274   LayerTreeImpl* pending_tree() { return pending_tree_.get(); }
 275   const LayerTreeImpl* pending_tree() const { return pending_tree_.get(); }
 276   const LayerTreeImpl* recycle_tree() const { return recycle_tree_.get(); }
 277   virtual void CreatePendingTree();
 278   virtual void UpdateVisibleTiles();
 279   virtual void ActivatePendingTree();
 280
 281   // Shortcuts to layers on the active tree.
 282   LayerImpl* RootLayer() const;
 283   LayerImpl* InnerViewportScrollLayer() const;
 284   LayerImpl* OuterViewportScrollLayer() const;
 285   LayerImpl* CurrentlyScrollingLayer() const;
 286
 287   int scroll_layer_id_when_mouse_over_scrollbar() {
 288     return scroll_layer_id_when_mouse_over_scrollbar_;
 289   }
 290
 291   bool IsCurrentlyScrolling() const;
 292
 293   virtual void SetVisible(bool visible);
 294   bool visible() const { return visible_; }
 295
 296   void SetNeedsCommit() { client_->SetNeedsCommitOnImplThread(); }
 297   void SetNeedsRedraw();
 298
 299   ManagedMemoryPolicy ActualManagedMemoryPolicy() const;
 300
 301   size_t memory_allocation_limit_bytes() const;
 302   int memory_allocation_priority_cutoff() const;
 303
 304   void SetViewportSize(const gfx::Size& device_viewport_size);
 305
 306   void SetOverdrawBottomHeight(float overdraw_bottom_height);
 307   float overdraw_bottom_height() const { return overdraw_bottom_height_; }
 308
 309   void SetOverhangUIResource(UIResourceId overhang_ui_resource_id,
 310                              const gfx::Size& overhang_ui_resource_size);
 311
 312   void SetDeviceScaleFactor(float device_scale_factor);
 313   float device_scale_factor() const { return device_scale_factor_; }
 314
 315   const gfx::Transform& DrawTransform() const;
 316
 317   scoped_ptr<ScrollAndScaleSet> ProcessScrollDeltas();
 318
 319   bool needs_animate_layers() const {
 320     return !animation_registrar_->active_animation_controllers().empty();
 321   }
 322
 323   void SendManagedMemoryStats(
 324       size_t memory_visible_bytes,
 325       size_t memory_visible_and_nearby_bytes,
 326       size_t memory_use_bytes);
 327
 328   void set_max_memory_needed_bytes(size_t bytes) {
 329     max_memory_needed_bytes_ = bytes;
 330   }
 331
 332   FrameRateCounter* fps_counter() {
 333     return fps_counter_.get();
 334   }
 335   PaintTimeCounter* paint_time_counter() {
 336     return paint_time_counter_.get();
 337   }
 338   MemoryHistory* memory_history() {
 339     return memory_history_.get();
 340   }
 341   DebugRectHistory* debug_rect_history() {
 342     return debug_rect_history_.get();
 343   }
 344   ResourceProvider* resource_provider() {
 345     return resource_provider_.get();
 346   }
 347   TopControlsManager* top_controls_manager() {
 348     return top_controls_manager_.get();
 349   }
 350   const GlobalStateThatImpactsTilePriority& global_tile_state() {
 351     return global_tile_state_;
 352   }
 353
 354   Proxy* proxy() const { return proxy_; }
 355
 356   AnimationRegistrar* animation_registrar() const {
 357     return animation_registrar_.get();
 358   }
 359
 360   void SetDebugState(const LayerTreeDebugState& new_debug_state);
 361   const LayerTreeDebugState& debug_state() const { return debug_state_; }
 362
 363   class CC_EXPORT CullRenderPassesWithNoQuads {
 364  public:
 365     bool ShouldRemoveRenderPass(const RenderPassDrawQuad& quad,
 366                                 const FrameData& frame) const;
 367
 368     // Iterates in draw order, so that when a surface is removed, and its
 369     // target becomes empty, then its target can be removed also.
 370     size_t RenderPassListBegin(const RenderPassList& list) const { return 0; }
 371     size_t RenderPassListEnd(const RenderPassList& list) const {
 372       return list.size();
 373     }
 374     size_t RenderPassListNext(size_t it) const { return it + 1; }
 375   };
 376
 377   template <typename RenderPassCuller>
 378       static void RemoveRenderPasses(RenderPassCuller culler, FrameData* frame);
 379
 380   gfx::Vector2dF accumulated_root_overscroll() const {
 381     return accumulated_root_overscroll_;
 382   }
 383   gfx::Vector2dF current_fling_velocity() const {
 384     return current_fling_velocity_;
 385   }
 386
 387   bool pinch_gesture_active() const { return pinch_gesture_active_; }
 388
 389   void SetTreePriority(TreePriority priority);
 390
 391   void UpdateCurrentFrameTime();
 392   void ResetCurrentFrameTimeForNextFrame();
 393   virtual base::TimeTicks CurrentFrameTimeTicks();
 394
 395   scoped_ptr<base::Value> AsValue() const { return AsValueWithFrame(NULL); }
 396   scoped_ptr<base::Value> AsValueWithFrame(FrameData* frame) const;
 397   scoped_ptr<base::Value> ActivationStateAsValue() const;
 398
 399   bool page_scale_animation_active() const { return !!page_scale_animation_; }
 400
 401   virtual void CreateUIResource(UIResourceId uid,
 402                                 const UIResourceBitmap& bitmap);
 403   // Deletes a UI resource.  May safely be called more than once.
 404   virtual void DeleteUIResource(UIResourceId uid);
 405   void EvictAllUIResources();
 406   bool EvictedUIResourcesExist() const;
 407
 408   virtual ResourceProvider::ResourceId ResourceIdForUIResource(
 409       UIResourceId uid) const;
 410
 411   virtual bool IsUIResourceOpaque(UIResourceId uid) const;
 412
 413   struct UIResourceData {
 414     ResourceProvider::ResourceId resource_id;
 415     gfx::Size size;
 416     bool opaque;
 417   };
 418
 419   void ScheduleMicroBenchmark(scoped_ptr<MicroBenchmarkImpl> benchmark);
 420
 421   CompositorFrameMetadata MakeCompositorFrameMetadata() const;
 422   // Viewport rectangle and clip in nonflipped window space.  These rects
 423   // should only be used by Renderer subclasses to populate glViewport/glClip
 424   // and their software-mode equivalents.
 425   gfx::Rect DeviceViewport() const;
 426   gfx::Rect DeviceClip() const;
 427
 428   // When a SwapPromiseMonitor is created on the impl thread, it calls
 429   // InsertSwapPromiseMonitor() to register itself with LayerTreeHostImpl.
 430   // When the monitor is destroyed, it calls RemoveSwapPromiseMonitor()
 431   // to unregister itself.
 432   void InsertSwapPromiseMonitor(SwapPromiseMonitor* monitor);
 433   void RemoveSwapPromiseMonitor(SwapPromiseMonitor* monitor);
 434
 435  protected:
 436   LayerTreeHostImpl(
 437       const LayerTreeSettings& settings,
 438       LayerTreeHostImplClient* client,
 439       Proxy* proxy,
 440       RenderingStatsInstrumentation* rendering_stats_instrumentation,
 441       SharedBitmapManager* manager,
 442       int id);
 443
 444   gfx::SizeF ComputeInnerViewportContainerSize() const;
 445   void UpdateInnerViewportContainerSize();
 446
 447   // Virtual for testing.
 448   virtual void AnimateLayers(base::TimeTicks monotonic_time);
 449
 450   // Virtual for testing.
 451   virtual base::TimeDelta LowFrequencyAnimationInterval() const;
 452
 453   const AnimationRegistrar::AnimationControllerMap&
 454       active_animation_controllers() const {
 455     return animation_registrar_->active_animation_controllers();
 456   }
 457
 458   bool manage_tiles_needed() const { return tile_priorities_dirty_; }
 459
 460   LayerTreeHostImplClient* client_;
 461   Proxy* proxy_;
 462
 463  private:
 464   void CreateAndSetRenderer(
 465       OutputSurface* output_surface,
 466       ResourceProvider* resource_provider,
 467       bool skip_gl_renderer);
 468   void CreateAndSetTileManager(ResourceProvider* resource_provider,
 469                                ContextProvider* context_provider,
 470                                bool using_map_image,
 471                                bool allow_rasterize_on_demand);
 472   void ReleaseTreeResources();
 473   void EnforceZeroBudget(bool zero_budget);
 474
 475   void ScrollViewportBy(gfx::Vector2dF scroll_delta);
 476   void AnimatePageScale(base::TimeTicks monotonic_time);
 477   void AnimateScrollbars(base::TimeTicks monotonic_time);
 478   void AnimateTopControls(base::TimeTicks monotonic_time);
 479
 480   gfx::Vector2dF ScrollLayerWithViewportSpaceDelta(
 481       LayerImpl* layer_impl,
 482       float scale_from_viewport_to_screen_space,
 483       const gfx::PointF& viewport_point,
 484       const gfx::Vector2dF& viewport_delta);
 485
 486   void TrackDamageForAllSurfaces(
 487       LayerImpl* root_draw_layer,
 488       const LayerImplList& render_surface_layer_list);
 489
 490   void UpdateTileManagerMemoryPolicy(const ManagedMemoryPolicy& policy);
 491
 492   // This function should only be called from PrepareToDraw, as DidDrawAllLayers
 493   // must be called if this helper function is called.  Returns DRAW_SUCCESS if
 494   // the frame should be drawn.
 495   DrawSwapReadbackResult::DrawResult CalculateRenderPasses(FrameData* frame);
 496
 497   void SendReleaseResourcesRecursive(LayerImpl* current);
 498   bool EnsureRenderSurfaceLayerList();
 499   void ClearCurrentlyScrollingLayer();
 500
 501   bool HandleMouseOverScrollbar(LayerImpl* layer_impl,
 502                                 const gfx::PointF& device_viewport_point);
 503
 504   void AnimateScrollbarsRecursive(LayerImpl* layer,
 505                                   base::TimeTicks time);
 506
 507   LayerImpl* FindScrollLayerForDeviceViewportPoint(
 508       const gfx::PointF& device_viewport_point,
 509       InputHandler::ScrollInputType type,
 510       LayerImpl* layer_hit_by_point,
 511       bool* scroll_on_main_thread) const;
 512   float DeviceSpaceDistanceToLayer(const gfx::PointF& device_viewport_point,
 513                                    LayerImpl* layer_impl);
 514   void StartScrollbarAnimationRecursive(LayerImpl* layer, base::TimeTicks time);
 515   void SetManagedMemoryPolicy(const ManagedMemoryPolicy& policy,
 516                               bool zero_budget);
 517   void EnforceManagedMemoryPolicy(const ManagedMemoryPolicy& policy);
 518
 519   void DidInitializeVisibleTile();
 520
 521   void MarkUIResourceNotEvicted(UIResourceId uid);
 522
 523   void NotifySwapPromiseMonitorsOfSetNeedsRedraw();
 524
 525   typedef base::hash_map<UIResourceId, UIResourceData>
 526       UIResourceMap;
 527   UIResourceMap ui_resource_map_;
 528
 529   // Resources that were evicted by EvictAllUIResources. Resources are removed
 530   // from this when they are touched by a create or destroy from the UI resource
 531   // request queue.
 532   std::set<UIResourceId> evicted_ui_resources_;
 533
 534   scoped_ptr<OutputSurface> output_surface_;
 535   scoped_refptr<ContextProvider> offscreen_context_provider_;
 536
 537   // |resource_provider_| and |tile_manager_| can be NULL, e.g. when using tile-
 538   // free rendering - see OutputSurface::ForcedDrawToSoftwareDevice().
 539   scoped_ptr<ResourceProvider> resource_provider_;
 540   scoped_ptr<TileManager> tile_manager_;
 541   scoped_ptr<Renderer> renderer_;
 542
 543   GlobalStateThatImpactsTilePriority global_tile_state_;
 544
 545   // Tree currently being drawn.
 546   scoped_ptr<LayerTreeImpl> active_tree_;
 547
 548   // In impl-side painting mode, tree with possibly incomplete rasterized
 549   // content. May be promoted to active by ActivatePendingTree().
 550   scoped_ptr<LayerTreeImpl> pending_tree_;
 551
 552   // In impl-side painting mode, inert tree with layers that can be recycled
 553   // by the next sync from the main thread.
 554   scoped_ptr<LayerTreeImpl> recycle_tree_;
 555
 556   InputHandlerClient* input_handler_client_;
 557   bool did_lock_scrolling_layer_;
 558   bool should_bubble_scrolls_;
 559   bool wheel_scrolling_;
 560   int scroll_layer_id_when_mouse_over_scrollbar_;
 561
 562   bool tile_priorities_dirty_;
 563
 564   // The optional delegate for the root layer scroll offset.
 565   LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate_;
 566   LayerTreeSettings settings_;
 567   LayerTreeDebugState debug_state_;
 568   bool visible_;
 569   ManagedMemoryPolicy cached_managed_memory_policy_;
 570
 571   gfx::Vector2dF accumulated_root_overscroll_;
 572   gfx::Vector2dF current_fling_velocity_;
 573
 574   bool pinch_gesture_active_;
 575   bool pinch_gesture_end_should_clear_scrolling_layer_;
 576   gfx::Point previous_pinch_anchor_;
 577
 578   scoped_ptr<TopControlsManager> top_controls_manager_;
 579
 580   scoped_ptr<PageScaleAnimation> page_scale_animation_;
 581
 582   // This is used for ticking animations slowly when hidden.
 583   scoped_ptr<LayerTreeHostImplTimeSourceAdapter> time_source_client_adapter_;
 584
 585   scoped_ptr<FrameRateCounter> fps_counter_;
 586   scoped_ptr<PaintTimeCounter> paint_time_counter_;
 587   scoped_ptr<MemoryHistory> memory_history_;
 588   scoped_ptr<DebugRectHistory> debug_rect_history_;
 589
 590   scoped_ptr<TextureMailboxDeleter> texture_mailbox_deleter_;
 591
 592   // The maximum memory that would be used by the prioritized resource
 593   // manager, if there were no limit on memory usage.
 594   size_t max_memory_needed_bytes_;
 595
 596   size_t last_sent_memory_visible_bytes_;
 597   size_t last_sent_memory_visible_and_nearby_bytes_;
 598   size_t last_sent_memory_use_bytes_;
 599   bool zero_budget_;
 600
 601   // Viewport size passed in from the main thread, in physical pixels.  This
 602   // value is the default size for all concepts of physical viewport (draw
 603   // viewport, scrolling viewport and device viewport), but it can be
 604   // overridden.
 605   gfx::Size device_viewport_size_;
 606
 607   // Conversion factor from CSS pixels to physical pixels when
 608   // pageScaleFactor=1.
 609   float device_scale_factor_;
 610
 611   // UI resource to use for drawing overhang gutters.
 612   UIResourceId overhang_ui_resource_id_;
 613   gfx::Size overhang_ui_resource_size_;
 614
 615   // Vertical amount of the viewport size that's known to covered by a
 616   // browser-side UI element, such as an on-screen-keyboard.  This affects
 617   // scrollable size since we want to still be able to scroll to the bottom of
 618   // the page when the keyboard is up.
 619   float overdraw_bottom_height_;
 620
 621   // Optional top-level constraints that can be set by the OutputSurface.
 622   // - external_transform_ applies a transform above the root layer
 623   // - external_viewport_ is used DrawProperties, tile management and
 624   // glViewport/window projection matrix.
 625   // - external_clip_ specifies a top-level clip rect
 626   // - external_stencil_test_enabled_ tells CC to respect existing stencil bits
 627   // (When these are specified, device_viewport_size_ remains used only for
 628   // scrollable size.)
 629   gfx::Transform external_transform_;
 630   gfx::Rect external_viewport_;
 631   gfx::Rect external_clip_;
 632   bool device_viewport_valid_for_tile_management_;
 633   bool external_stencil_test_enabled_;
 634
 635   gfx::Rect viewport_damage_rect_;
 636
 637   base::TimeTicks current_frame_timeticks_;
 638
 639   scoped_ptr<AnimationRegistrar> animation_registrar_;
 640
 641   RenderingStatsInstrumentation* rendering_stats_instrumentation_;
 642   MicroBenchmarkControllerImpl micro_benchmark_controller_;
 643
 644   bool need_to_update_visible_tiles_before_draw_;
 645 #if DCHECK_IS_ON
 646   bool did_lose_called_;
 647 #endif
 648
 649   // Optional callback to notify of new tree activations.
 650   base::Closure tree_activation_callback_;
 651
 652   SharedBitmapManager* shared_bitmap_manager_;
 653   int id_;
 654
 655   std::set<SwapPromiseMonitor*> swap_promise_monitor_;
 656
 657   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 658 };
 659
 660 }  // namespace cc
 661
 662 #endif  // CC_TREES_LAYER_TREE_HOST_IMPL_H_