cc/layers/layer.h

   1 // Copyright 2010 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_LAYERS_LAYER_H_
   6 #define CC_LAYERS_LAYER_H_
   7
   8 #include <set>
   9 #include <string>
  10 #include <vector>
  11
  12 #include "base/callback.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/observer_list.h"
  15 #include "cc/animation/layer_animation_controller.h"
  16 #include "cc/animation/layer_animation_value_observer.h"
  17 #include "cc/animation/layer_animation_value_provider.h"
  18 #include "cc/base/cc_export.h"
  19 #include "cc/base/region.h"
  20 #include "cc/base/scoped_ptr_vector.h"
  21 #include "cc/debug/frame_timing_request.h"
  22 #include "cc/debug/micro_benchmark.h"
  23 #include "cc/layers/draw_properties.h"
  24 #include "cc/layers/layer_lists.h"
  25 #include "cc/layers/layer_position_constraint.h"
  26 #include "cc/layers/paint_properties.h"
  27 #include "cc/layers/render_surface.h"
  28 #include "cc/layers/scroll_blocks_on.h"
  29 #include "cc/output/filter_operations.h"
  30 #include "cc/trees/property_tree.h"
  31 #include "skia/ext/refptr.h"
  32 #include "third_party/skia/include/core/SkColor.h"
  33 #include "third_party/skia/include/core/SkImageFilter.h"
  34 #include "third_party/skia/include/core/SkPicture.h"
  35 #include "third_party/skia/include/core/SkXfermode.h"
  36 #include "ui/gfx/geometry/point3_f.h"
  37 #include "ui/gfx/geometry/rect.h"
  38 #include "ui/gfx/geometry/rect_f.h"
  39 #include "ui/gfx/geometry/scroll_offset.h"
  40 #include "ui/gfx/transform.h"
  41
  42 namespace gfx {
  43 class BoxF;
  44 }
  45
  46 namespace base {
  47 namespace trace_event {
  48 class ConvertableToTraceFormat;
  49 }
  50 }
  51
  52 namespace cc {
  53
  54 class Animation;
  55 class AnimationDelegate;
  56 struct AnimationEvent;
  57 class CopyOutputRequest;
  58 class LayerAnimationEventObserver;
  59 class LayerClient;
  60 class LayerImpl;
  61 class LayerSettings;
  62 class LayerTreeHost;
  63 class LayerTreeHostCommon;
  64 class LayerTreeImpl;
  65 class LayerTreeSettings;
  66 class RenderingStatsInstrumentation;
  67 class ResourceUpdateQueue;
  68 class ScrollbarLayerInterface;
  69 class SimpleEnclosedRegion;
  70 struct AnimationEvent;
  71
  72 // Base class for composited layers. Special layer types are derived from
  73 // this class.
  74 class CC_EXPORT Layer : public base::RefCounted<Layer>,
  75                         public LayerAnimationValueObserver,
  76                         public LayerAnimationValueProvider {
  77  public:
  78   typedef RenderSurfaceLayerList RenderSurfaceListType;
  79   typedef LayerList LayerListType;
  80   typedef RenderSurface RenderSurfaceType;
  81
  82   enum LayerIdLabels {
  83     INVALID_ID = -1,
  84   };
  85
  86   static scoped_refptr<Layer> Create(const LayerSettings& settings);
  87
  88   int id() const { return layer_id_; }
  89
  90   Layer* RootLayer();
  91   Layer* parent() { return parent_; }
  92   const Layer* parent() const { return parent_; }
  93   void AddChild(scoped_refptr<Layer> child);
  94   void InsertChild(scoped_refptr<Layer> child, size_t index);
  95   void ReplaceChild(Layer* reference, scoped_refptr<Layer> new_layer);
  96   void RemoveFromParent();
  97   void RemoveAllChildren();
  98   void SetChildren(const LayerList& children);
  99   bool HasAncestor(const Layer* ancestor) const;
 100
 101   const LayerList& children() const { return children_; }
 102   Layer* child_at(size_t index) { return children_[index].get(); }
 103
 104   // This requests the layer and its subtree be rendered and given to the
 105   // callback. If the copy is unable to be produced (the layer is destroyed
 106   // first), then the callback is called with a nullptr/empty result. If the
 107   // request's source property is set, any prior uncommitted requests having the
 108   // same source will be aborted.
 109   void RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> request);
 110   bool HasCopyRequest() const {
 111     return !copy_requests_.empty();
 112   }
 113
 114   virtual void SetBackgroundColor(SkColor background_color);
 115   SkColor background_color() const { return background_color_; }
 116   // If contents_opaque(), return an opaque color else return a
 117   // non-opaque color.  Tries to return background_color(), if possible.
 118   SkColor SafeOpaqueBackgroundColor() const;
 119
 120   // A layer's bounds are in logical, non-page-scaled pixels (however, the
 121   // root layer's bounds are in physical pixels).
 122   void SetBounds(const gfx::Size& bounds);
 123   gfx::Size bounds() const { return bounds_; }
 124
 125   void SetMasksToBounds(bool masks_to_bounds);
 126   bool masks_to_bounds() const { return masks_to_bounds_; }
 127
 128   void SetMaskLayer(Layer* mask_layer);
 129   Layer* mask_layer() { return mask_layer_.get(); }
 130   const Layer* mask_layer() const { return mask_layer_.get(); }
 131
 132   virtual void SetNeedsDisplayRect(const gfx::Rect& dirty_rect);
 133   void SetNeedsDisplay() { SetNeedsDisplayRect(gfx::Rect(bounds())); }
 134
 135   void SetOpacity(float opacity);
 136   float opacity() const { return opacity_; }
 137   bool OpacityIsAnimating() const;
 138   bool HasPotentiallyRunningOpacityAnimation() const;
 139   virtual bool OpacityCanAnimateOnImplThread() const;
 140
 141   void SetBlendMode(SkXfermode::Mode blend_mode);
 142   SkXfermode::Mode blend_mode() const { return blend_mode_; }
 143
 144   bool uses_default_blend_mode() const {
 145     return blend_mode_ == SkXfermode::kSrcOver_Mode;
 146   }
 147
 148   // A layer is root for an isolated group when it and all its descendants are
 149   // drawn over a black and fully transparent background, creating an isolated
 150   // group. It should be used along with SetBlendMode(), in order to restrict
 151   // layers within the group to blend with layers outside this group.
 152   void SetIsRootForIsolatedGroup(bool root);
 153   bool is_root_for_isolated_group() const {
 154     return is_root_for_isolated_group_;
 155   }
 156
 157   void SetFilters(const FilterOperations& filters);
 158   const FilterOperations& filters() const { return filters_; }
 159   bool FilterIsAnimating() const;
 160
 161   // Background filters are filters applied to what is behind this layer, when
 162   // they are viewed through non-opaque regions in this layer. They are used
 163   // through the WebLayer interface, and are not exposed to HTML.
 164   void SetBackgroundFilters(const FilterOperations& filters);
 165   const FilterOperations& background_filters() const {
 166     return background_filters_;
 167   }
 168
 169   virtual void SetContentsOpaque(bool opaque);
 170   bool contents_opaque() const { return contents_opaque_; }
 171
 172   void SetPosition(const gfx::PointF& position);
 173   gfx::PointF position() const { return position_; }
 174
 175   // A layer that is a container for fixed position layers cannot be both
 176   // scrollable and have a non-identity transform.
 177   void SetIsContainerForFixedPositionLayers(bool container);
 178   bool IsContainerForFixedPositionLayers() const;
 179
 180   gfx::Vector2dF FixedContainerSizeDelta() const {
 181     return gfx::Vector2dF();
 182   }
 183
 184   void SetPositionConstraint(const LayerPositionConstraint& constraint);
 185   const LayerPositionConstraint& position_constraint() const {
 186     return position_constraint_;
 187   }
 188
 189   void SetTransform(const gfx::Transform& transform);
 190   const gfx::Transform& transform() const { return transform_; }
 191   bool TransformIsAnimating() const;
 192   bool HasPotentiallyRunningTransformAnimation() const;
 193   bool AnimationsPreserveAxisAlignment() const;
 194   bool transform_is_invertible() const { return transform_is_invertible_; }
 195
 196   void SetTransformOrigin(const gfx::Point3F&);
 197   gfx::Point3F transform_origin() const { return transform_origin_; }
 198
 199   bool ScrollOffsetAnimationWasInterrupted() const;
 200
 201   void SetScrollParent(Layer* parent);
 202
 203   Layer* scroll_parent() { return scroll_parent_; }
 204   const Layer* scroll_parent() const { return scroll_parent_; }
 205
 206   void AddScrollChild(Layer* child);
 207   void RemoveScrollChild(Layer* child);
 208
 209   std::set<Layer*>* scroll_children() { return scroll_children_.get(); }
 210   const std::set<Layer*>* scroll_children() const {
 211     return scroll_children_.get();
 212   }
 213
 214   void SetClipParent(Layer* ancestor);
 215
 216   Layer* clip_parent() { return clip_parent_; }
 217   const Layer* clip_parent() const {
 218     return clip_parent_;
 219   }
 220
 221   void AddClipChild(Layer* child);
 222   void RemoveClipChild(Layer* child);
 223
 224   std::set<Layer*>* clip_children() { return clip_children_.get(); }
 225   const std::set<Layer*>* clip_children() const {
 226     return clip_children_.get();
 227   }
 228
 229   DrawProperties<Layer>& draw_properties() { return draw_properties_; }
 230   const DrawProperties<Layer>& draw_properties() const {
 231     return draw_properties_;
 232   }
 233
 234   // The following are shortcut accessors to get various information from
 235   // draw_properties_
 236   const gfx::Transform& draw_transform() const {
 237     return draw_properties_.target_space_transform;
 238   }
 239   const gfx::Transform& screen_space_transform() const {
 240     return draw_properties_.screen_space_transform;
 241   }
 242   float draw_opacity() const { return draw_properties_.opacity; }
 243   bool draw_transform_is_animating() const {
 244     return draw_properties_.target_space_transform_is_animating;
 245   }
 246   bool screen_space_transform_is_animating() const {
 247     return draw_properties_.screen_space_transform_is_animating;
 248   }
 249   gfx::Rect clip_rect() const { return draw_properties_.clip_rect; }
 250   gfx::Rect drawable_content_rect() const {
 251     return draw_properties_.drawable_content_rect;
 252   }
 253   gfx::Rect visible_layer_rect() const {
 254     return draw_properties_.visible_layer_rect;
 255   }
 256   Layer* render_target() {
 257     DCHECK(!draw_properties_.render_target ||
 258            draw_properties_.render_target->render_surface());
 259     return draw_properties_.render_target;
 260   }
 261   const Layer* render_target() const {
 262     DCHECK(!draw_properties_.render_target ||
 263            draw_properties_.render_target->render_surface());
 264     return draw_properties_.render_target;
 265   }
 266   size_t num_unclipped_descendants() const {
 267     return draw_properties_.num_unclipped_descendants;
 268   }
 269
 270   RenderSurface* render_surface() const { return render_surface_.get(); }
 271   void SetScrollOffset(const gfx::ScrollOffset& scroll_offset);
 272   void SetScrollCompensationAdjustment(
 273       const gfx::Vector2dF& scroll_compensation_adjustment);
 274   gfx::Vector2dF ScrollCompensationAdjustment() const;
 275
 276   gfx::ScrollOffset scroll_offset() const { return scroll_offset_; }
 277   void SetScrollOffsetFromImplSide(const gfx::ScrollOffset& scroll_offset);
 278
 279   void SetScrollClipLayerId(int clip_layer_id);
 280   bool scrollable() const { return scroll_clip_layer_id_ != INVALID_ID; }
 281
 282   void SetUserScrollable(bool horizontal, bool vertical);
 283   bool user_scrollable_horizontal() const {
 284     return user_scrollable_horizontal_;
 285   }
 286   bool user_scrollable_vertical() const { return user_scrollable_vertical_; }
 287
 288   void SetShouldScrollOnMainThread(bool should_scroll_on_main_thread);
 289   bool should_scroll_on_main_thread() const {
 290     return should_scroll_on_main_thread_;
 291   }
 292
 293   void SetHaveWheelEventHandlers(bool have_wheel_event_handlers);
 294   bool have_wheel_event_handlers() const { return have_wheel_event_handlers_; }
 295
 296   void SetHaveScrollEventHandlers(bool have_scroll_event_handlers);
 297   bool have_scroll_event_handlers() const {
 298     return have_scroll_event_handlers_;
 299   }
 300
 301   void SetNonFastScrollableRegion(const Region& non_fast_scrollable_region);
 302   const Region& non_fast_scrollable_region() const {
 303     return non_fast_scrollable_region_;
 304   }
 305
 306   void SetTouchEventHandlerRegion(const Region& touch_event_handler_region);
 307   const Region& touch_event_handler_region() const {
 308     return touch_event_handler_region_;
 309   }
 310
 311   void SetScrollBlocksOn(ScrollBlocksOn scroll_blocks_on);
 312   ScrollBlocksOn scroll_blocks_on() const { return scroll_blocks_on_; }
 313
 314   void set_did_scroll_callback(const base::Closure& callback) {
 315     did_scroll_callback_ = callback;
 316   }
 317
 318   void SetDrawCheckerboardForMissingTiles(bool checkerboard);
 319   bool draw_checkerboard_for_missing_tiles() const {
 320     return draw_checkerboard_for_missing_tiles_;
 321   }
 322
 323   void SetForceRenderSurface(bool force_render_surface);
 324   bool force_render_surface() const { return force_render_surface_; }
 325
 326   gfx::Vector2dF ScrollDelta() const { return gfx::Vector2dF(); }
 327   gfx::ScrollOffset CurrentScrollOffset() const { return scroll_offset_; }
 328
 329   void SetDoubleSided(bool double_sided);
 330   bool double_sided() const { return double_sided_; }
 331
 332   void SetShouldFlattenTransform(bool flatten);
 333   bool should_flatten_transform() const { return should_flatten_transform_; }
 334
 335   bool Is3dSorted() const { return sorting_context_id_ != 0; }
 336
 337   void set_use_parent_backface_visibility(bool use) {
 338     use_parent_backface_visibility_ = use;
 339   }
 340   bool use_parent_backface_visibility() const {
 341     return use_parent_backface_visibility_;
 342   }
 343
 344   virtual void SetLayerTreeHost(LayerTreeHost* host);
 345
 346   virtual bool HasDelegatedContent() const;
 347   bool HasContributingDelegatedRenderPasses() const { return false; }
 348
 349   void SetIsDrawable(bool is_drawable);
 350
 351   void SetHideLayerAndSubtree(bool hide);
 352   bool hide_layer_and_subtree() const { return hide_layer_and_subtree_; }
 353
 354   void SetReplicaLayer(Layer* layer);
 355   Layer* replica_layer() { return replica_layer_.get(); }
 356   const Layer* replica_layer() const { return replica_layer_.get(); }
 357
 358   bool has_mask() const { return !!mask_layer_.get(); }
 359   bool has_replica() const { return !!replica_layer_.get(); }
 360   bool replica_has_mask() const {
 361     return replica_layer_.get() &&
 362            (mask_layer_.get() || replica_layer_->mask_layer_.get());
 363   }
 364
 365   int NumDescendantsThatDrawContent() const;
 366
 367   // This is only virtual for tests.
 368   // TODO(awoloszyn): Remove this once we no longer need it for tests
 369   virtual bool DrawsContent() const;
 370
 371   // This methods typically need to be overwritten by derived classes.
 372   virtual void SavePaintProperties();
 373   // Returns true iff anything was updated that needs to be committed.
 374   virtual bool Update();
 375   virtual bool NeedMoreUpdates();
 376   virtual void SetIsMask(bool is_mask) {}
 377   virtual void ReduceMemoryUsage() {}
 378   virtual void OnOutputSurfaceCreated() {}
 379   virtual bool IsSuitableForGpuRasterization() const;
 380
 381   virtual scoped_refptr<base::trace_event::ConvertableToTraceFormat>
 382   TakeDebugInfo();
 383
 384   void SetLayerClient(LayerClient* client) { client_ = client; }
 385
 386   virtual void PushPropertiesTo(LayerImpl* layer);
 387
 388   void CreateRenderSurface();
 389   void ClearRenderSurface();
 390
 391   void ClearRenderSurfaceLayerList();
 392
 393   LayerTreeHost* layer_tree_host() { return layer_tree_host_; }
 394   const LayerTreeHost* layer_tree_host() const { return layer_tree_host_; }
 395
 396   bool AddAnimation(scoped_ptr<Animation> animation);
 397   void PauseAnimation(int animation_id, double time_offset);
 398   void RemoveAnimation(int animation_id);
 399   void RemoveAnimation(int animation_id, Animation::TargetProperty property);
 400   LayerAnimationController* layer_animation_controller() const {
 401     return layer_animation_controller_.get();
 402   }
 403   void SetLayerAnimationControllerForTest(
 404       scoped_refptr<LayerAnimationController> controller);
 405
 406   void set_layer_animation_delegate(AnimationDelegate* delegate) {
 407     DCHECK(layer_animation_controller_);
 408     layer_animation_controller_->set_layer_animation_delegate(delegate);
 409   }
 410
 411   bool HasActiveAnimation() const;
 412   void RegisterForAnimations(AnimationRegistrar* registrar);
 413
 414   void AddLayerAnimationEventObserver(
 415       LayerAnimationEventObserver* animation_observer);
 416   void RemoveLayerAnimationEventObserver(
 417       LayerAnimationEventObserver* animation_observer);
 418
 419   virtual ScrollbarLayerInterface* ToScrollbarLayer();
 420
 421   virtual skia::RefPtr<SkPicture> GetPicture() const;
 422
 423   // Constructs a LayerImpl of the correct runtime type for this Layer type.
 424   virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl);
 425
 426   bool NeedsDisplayForTesting() const { return !update_rect_.IsEmpty(); }
 427   void ResetNeedsDisplayForTesting() { update_rect_ = gfx::Rect(); }
 428
 429   RenderingStatsInstrumentation* rendering_stats_instrumentation() const;
 430
 431   const PaintProperties& paint_properties() const {
 432     return paint_properties_;
 433   }
 434
 435   void SetNeedsPushProperties();
 436   bool needs_push_properties() const { return needs_push_properties_; }
 437   bool descendant_needs_push_properties() const {
 438     return num_dependents_need_push_properties_ > 0;
 439   }
 440   void reset_needs_push_properties_for_testing() {
 441     needs_push_properties_ = false;
 442   }
 443
 444   virtual void RunMicroBenchmark(MicroBenchmark* benchmark);
 445
 446   void Set3dSortingContextId(int id);
 447   int sorting_context_id() const { return sorting_context_id_; }
 448
 449   void set_property_tree_sequence_number(int sequence_number) {
 450     property_tree_sequence_number_ = sequence_number;
 451   }
 452
 453   void SetTransformTreeIndex(int index);
 454   int transform_tree_index() const;
 455
 456   void SetClipTreeIndex(int index);
 457   int clip_tree_index() const;
 458
 459   void SetOpacityTreeIndex(int index);
 460   int opacity_tree_index() const;
 461
 462   void set_offset_to_transform_parent(gfx::Vector2dF offset) {
 463     if (offset_to_transform_parent_ == offset)
 464       return;
 465     offset_to_transform_parent_ = offset;
 466     SetNeedsPushProperties();
 467   }
 468   gfx::Vector2dF offset_to_transform_parent() const {
 469     return offset_to_transform_parent_;
 470   }
 471
 472   // TODO(vollick): Once we transition to transform and clip trees, rename these
 473   // functions and related values.  The "from property trees" functions below
 474   // use the transform and clip trees.  Eventually, we will use these functions
 475   // to compute the official values, but these functions are retained for
 476   // testing purposes until we've migrated.
 477
 478   const gfx::Rect& visible_rect_from_property_trees() const {
 479     return visible_rect_from_property_trees_;
 480   }
 481   void set_visible_rect_from_property_trees(const gfx::Rect& rect) {
 482     // No push properties here, as this acts like a draw property.
 483     visible_rect_from_property_trees_ = rect;
 484   }
 485
 486   void set_should_flatten_transform_from_property_tree(bool should_flatten) {
 487     if (should_flatten_transform_from_property_tree_ == should_flatten)
 488       return;
 489     should_flatten_transform_from_property_tree_ = should_flatten;
 490     SetNeedsPushProperties();
 491   }
 492   bool should_flatten_transform_from_property_tree() const {
 493     return should_flatten_transform_from_property_tree_;
 494   }
 495
 496   void set_is_clipped(bool is_clipped) {
 497     if (is_clipped_ == is_clipped)
 498       return;
 499     is_clipped_ = is_clipped;
 500     SetNeedsPushProperties();
 501   }
 502   bool is_clipped() const { return is_clipped_; }
 503
 504   // TODO(vollick): These values are temporary and will be removed as soon as
 505   // render surface determinations are moved out of CDP. They only exist because
 506   // certain logic depends on whether or not a layer would render to a separate
 507   // surface, but CDP destroys surfaces and targets it doesn't need, so without
 508   // this boolean, this is impossible to determine after the fact without
 509   // wastefully recomputing it. This is public for the time being so that it can
 510   // be accessed from CDP.
 511   bool has_render_surface() const {
 512     return has_render_surface_;
 513   }
 514
 515   // Sets new frame timing requests for this layer.
 516   void SetFrameTimingRequests(const std::vector<FrameTimingRequest>& requests);
 517
 518   // Accessor for unit tests
 519   const std::vector<FrameTimingRequest>& FrameTimingRequests() const {
 520     return frame_timing_requests_;
 521   }
 522
 523   void DidBeginTracing();
 524   void set_num_layer_or_descandant_with_copy_request(
 525       int num_layer_or_descendants_with_copy_request) {
 526     num_layer_or_descendants_with_copy_request_ =
 527         num_layer_or_descendants_with_copy_request;
 528   }
 529
 530   void set_num_layer_or_descandant_with_input_handler(
 531       int num_layer_or_descendants_with_input_handler) {
 532     num_layer_or_descendants_with_input_handler_ =
 533         num_layer_or_descendants_with_input_handler;
 534   }
 535
 536   int num_layer_or_descendants_with_input_handler() {
 537     return num_layer_or_descendants_with_input_handler_;
 538   }
 539
 540   void set_num_children_with_scroll_parent(
 541       int num_children_with_scroll_parent) {
 542     num_children_with_scroll_parent_ = num_children_with_scroll_parent;
 543   }
 544
 545   int num_children_with_scroll_parent() {
 546     return num_children_with_scroll_parent_;
 547   }
 548
 549   void set_visited(bool visited);
 550   bool visited();
 551   void set_layer_or_descendant_is_drawn(bool layer_or_descendant_is_drawn);
 552   bool layer_or_descendant_is_drawn();
 553   void set_sorted_for_recursion(bool sorted_for_recursion);
 554   bool sorted_for_recursion();
 555
 556  protected:
 557   friend class LayerImpl;
 558   friend class TreeSynchronizer;
 559   ~Layer() override;
 560
 561   explicit Layer(const LayerSettings& settings);
 562
 563   // These SetNeeds functions are in order of severity of update:
 564   //
 565   // Called when this layer has been modified in some way, but isn't sure
 566   // that it needs a commit yet.  It needs CalcDrawProperties and UpdateLayers
 567   // before it knows whether or not a commit is required.
 568   void SetNeedsUpdate();
 569   // Called when a property has been modified in a way that the layer
 570   // knows immediately that a commit is required.  This implies SetNeedsUpdate
 571   // as well as SetNeedsPushProperties to push that property.
 572   void SetNeedsCommit();
 573   // This is identical to SetNeedsCommit, but the former requests a rebuild of
 574   // the property trees.
 575   void SetNeedsCommitNoRebuild();
 576   // Called when there's been a change in layer structure.  Implies both
 577   // SetNeedsUpdate and SetNeedsCommit, but not SetNeedsPushProperties.
 578   void SetNeedsFullTreeSync();
 579
 580   // Called when the next commit should wait until the pending tree is activated
 581   // before finishing the commit and unblocking the main thread. Used to ensure
 582   // unused resources on the impl thread are returned before commit completes.
 583   void SetNextCommitWaitsForActivation();
 584
 585   // Will recalculate whether the layer draws content and set draws_content_
 586   // appropriately.
 587   void UpdateDrawsContent(bool has_drawable_content);
 588   virtual bool HasDrawableContent() const;
 589
 590   // Called when the layer's number of drawable descendants changes.
 591   void AddDrawableDescendants(int num);
 592
 593   void AddDependentNeedsPushProperties();
 594   void RemoveDependentNeedsPushProperties();
 595   bool parent_should_know_need_push_properties() const {
 596     return needs_push_properties() || descendant_needs_push_properties();
 597   }
 598
 599   bool IsPropertyChangeAllowed() const;
 600
 601   // This flag is set when the layer needs to push properties to the impl
 602   // side.
 603   bool needs_push_properties_;
 604
 605   // The number of direct children or dependent layers that need to be recursed
 606   // to in order for them or a descendent of them to push properties to the impl
 607   // side.
 608   int num_dependents_need_push_properties_;
 609
 610   // Tracks whether this layer may have changed stacking order with its
 611   // siblings.
 612   bool stacking_order_changed_;
 613
 614   // The update rect is the region of the compositor resource that was
 615   // actually updated by the compositor. For layers that may do updating
 616   // outside the compositor's control (i.e. plugin layers), this information
 617   // is not available and the update rect will remain empty.
 618   // Note this rect is in layer space (not content space).
 619   gfx::Rect update_rect_;
 620
 621   scoped_refptr<Layer> mask_layer_;
 622
 623   int layer_id_;
 624
 625   // When true, the layer is about to perform an update. Any commit requests
 626   // will be handled implicitly after the update completes.
 627   bool ignore_set_needs_commit_;
 628
 629   // Layers that share a sorting context id will be sorted together in 3d
 630   // space.  0 is a special value that means this layer will not be sorted and
 631   // will be drawn in paint order.
 632   int sorting_context_id_;
 633
 634  private:
 635   friend class base::RefCounted<Layer>;
 636   friend class LayerTreeHostCommon;
 637   void SetParent(Layer* layer);
 638   bool DescendantIsFixedToContainerLayer() const;
 639
 640   // This should only be called during BeginMainFrame since it does not
 641   // trigger a Commit.
 642   void SetHasRenderSurface(bool has_render_surface);
 643
 644   // This should only be called from RemoveFromParent().
 645   void RemoveChildOrDependent(Layer* child);
 646
 647   // LayerAnimationValueProvider implementation.
 648   gfx::ScrollOffset ScrollOffsetForAnimation() const override;
 649
 650   // LayerAnimationValueObserver implementation.
 651   void OnFilterAnimated(const FilterOperations& filters) override;
 652   void OnOpacityAnimated(float opacity) override;
 653   void OnTransformAnimated(const gfx::Transform& transform) override;
 654   void OnScrollOffsetAnimated(const gfx::ScrollOffset& scroll_offset) override;
 655   void OnAnimationWaitingForDeletion() override;
 656   bool IsActive() const override;
 657
 658   // If this layer has a scroll parent, it removes |this| from its list of
 659   // scroll children.
 660   void RemoveFromScrollTree();
 661
 662   // If this layer has a clip parent, it removes |this| from its list of clip
 663   // children.
 664   void RemoveFromClipTree();
 665
 666   // When we detach or attach layer to new LayerTreeHost, all property trees'
 667   // indices becomes invalid.
 668   void InvalidatePropertyTreesIndices();
 669
 670   void UpdateNumCopyRequestsForSubtree(bool add);
 671   void UpdateNumInputHandlersForSubtree(bool add);
 672
 673   LayerList children_;
 674   Layer* parent_;
 675
 676   // Layer instances have a weak pointer to their LayerTreeHost.
 677   // This pointer value is nil when a Layer is not in a tree and is
 678   // updated via SetLayerTreeHost() if a layer moves between trees.
 679   LayerTreeHost* layer_tree_host_;
 680
 681   scoped_refptr<LayerAnimationController> layer_animation_controller_;
 682
 683   // Layer properties.
 684   gfx::Size bounds_;
 685
 686   gfx::ScrollOffset scroll_offset_;
 687   gfx::Vector2dF scroll_compensation_adjustment_;
 688   // This variable indicates which ancestor layer (if any) whose size,
 689   // transformed relative to this layer, defines the maximum scroll offset for
 690   // this layer.
 691   int scroll_clip_layer_id_;
 692   int num_descendants_that_draw_content_;
 693   int transform_tree_index_;
 694   int opacity_tree_index_;
 695   int clip_tree_index_;
 696   int property_tree_sequence_number_;
 697   int num_layer_or_descendants_with_copy_request_;
 698   int num_layer_or_descendants_with_input_handler_;
 699   int num_children_with_scroll_parent_;
 700   gfx::Vector2dF offset_to_transform_parent_;
 701   bool should_flatten_transform_from_property_tree_ : 1;
 702   bool is_clipped_ : 1;
 703   bool should_scroll_on_main_thread_ : 1;
 704   bool have_wheel_event_handlers_ : 1;
 705   bool have_scroll_event_handlers_ : 1;
 706   bool user_scrollable_horizontal_ : 1;
 707   bool user_scrollable_vertical_ : 1;
 708   bool is_root_for_isolated_group_ : 1;
 709   bool is_container_for_fixed_position_layers_ : 1;
 710   bool is_drawable_ : 1;
 711   bool draws_content_ : 1;
 712   bool hide_layer_and_subtree_ : 1;
 713   bool masks_to_bounds_ : 1;
 714   bool contents_opaque_ : 1;
 715   bool double_sided_ : 1;
 716   bool should_flatten_transform_ : 1;
 717   bool use_parent_backface_visibility_ : 1;
 718   bool draw_checkerboard_for_missing_tiles_ : 1;
 719   bool force_render_surface_ : 1;
 720   bool transform_is_invertible_ : 1;
 721   bool has_render_surface_ : 1;
 722   ScrollBlocksOn scroll_blocks_on_ : 3;
 723   Region non_fast_scrollable_region_;
 724   Region touch_event_handler_region_;
 725   gfx::PointF position_;
 726   SkColor background_color_;
 727   float opacity_;
 728   SkXfermode::Mode blend_mode_;
 729   FilterOperations filters_;
 730   FilterOperations background_filters_;
 731   LayerPositionConstraint position_constraint_;
 732   Layer* scroll_parent_;
 733   scoped_ptr<std::set<Layer*>> scroll_children_;
 734
 735   // The following three variables are tracker variables. They are bools
 736   // wrapped inside an integer variable. If true, their value equals the
 737   // LayerTreeHost's meta_information_sequence_number. This wrapping of bools
 738   // inside ints is done to avoid a layer tree treewalk to reset their values.
 739   int layer_or_descendant_is_drawn_tracker_;
 740   int sorted_for_recursion_tracker_;
 741   int visited_tracker_;
 742
 743   Layer* clip_parent_;
 744   scoped_ptr<std::set<Layer*>> clip_children_;
 745
 746   gfx::Transform transform_;
 747   gfx::Point3F transform_origin_;
 748
 749   // Replica layer used for reflections.
 750   scoped_refptr<Layer> replica_layer_;
 751
 752   LayerClient* client_;
 753
 754   ScopedPtrVector<CopyOutputRequest> copy_requests_;
 755
 756   base::Closure did_scroll_callback_;
 757
 758   DrawProperties<Layer> draw_properties_;
 759
 760   PaintProperties paint_properties_;
 761   // TODO(awoloszyn): This is redundant with has_render_surface_,
 762   // and should get removed once it is no longer needed on main thread.
 763   scoped_ptr<RenderSurface> render_surface_;
 764
 765   gfx::Rect visible_rect_from_property_trees_;
 766
 767   std::vector<FrameTimingRequest> frame_timing_requests_;
 768   bool frame_timing_requests_dirty_;
 769
 770   DISALLOW_COPY_AND_ASSIGN(Layer);
 771 };
 772
 773 }  // namespace cc
 774
 775 #endif  // CC_LAYERS_LAYER_H_