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 PriorityCalculator;
  67 class RenderingStatsInstrumentation;
  68 class ResourceUpdateQueue;
  69 class ScrollbarLayerInterface;
  70 class SimpleEnclosedRegion;
  71 struct AnimationEvent;
  72 template <typename LayerType>
  73 class OcclusionTracker;
  74
  75 // Base class for composited layers. Special layer types are derived from
  76 // this class.
  77 class CC_EXPORT Layer : public base::RefCounted<Layer>,
  78                         public LayerAnimationValueObserver,
  79                         public LayerAnimationValueProvider {
  80  public:
  81   typedef RenderSurfaceLayerList RenderSurfaceListType;
  82   typedef LayerList LayerListType;
  83   typedef RenderSurface RenderSurfaceType;
  84
  85   enum LayerIdLabels {
  86     INVALID_ID = -1,
  87   };
  88
  89   static scoped_refptr<Layer> Create(const LayerSettings& settings);
  90
  91   int id() const { return layer_id_; }
  92
  93   Layer* RootLayer();
  94   Layer* parent() { return parent_; }
  95   const Layer* parent() const { return parent_; }
  96   void AddChild(scoped_refptr<Layer> child);
  97   void InsertChild(scoped_refptr<Layer> child, size_t index);
  98   void ReplaceChild(Layer* reference, scoped_refptr<Layer> new_layer);
  99   void RemoveFromParent();
 100   void RemoveAllChildren();
 101   void SetChildren(const LayerList& children);
 102   bool HasAncestor(const Layer* ancestor) const;
 103
 104   const LayerList& children() const { return children_; }
 105   Layer* child_at(size_t index) { return children_[index].get(); }
 106
 107   // This requests the layer and its subtree be rendered and given to the
 108   // callback. If the copy is unable to be produced (the layer is destroyed
 109   // first), then the callback is called with a nullptr/empty result. If the
 110   // request's source property is set, any prior uncommitted requests having the
 111   // same source will be aborted.
 112   void RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> request);
 113   bool HasCopyRequest() const {
 114     return !copy_requests_.empty();
 115   }
 116
 117   virtual void SetBackgroundColor(SkColor background_color);
 118   SkColor background_color() const { return background_color_; }
 119   // If contents_opaque(), return an opaque color else return a
 120   // non-opaque color.  Tries to return background_color(), if possible.
 121   SkColor SafeOpaqueBackgroundColor() const;
 122
 123   // A layer's bounds are in logical, non-page-scaled pixels (however, the
 124   // root layer's bounds are in physical pixels).
 125   void SetBounds(const gfx::Size& bounds);
 126   gfx::Size bounds() const { return bounds_; }
 127
 128   void SetMasksToBounds(bool masks_to_bounds);
 129   bool masks_to_bounds() const { return masks_to_bounds_; }
 130
 131   void SetMaskLayer(Layer* mask_layer);
 132   Layer* mask_layer() { return mask_layer_.get(); }
 133   const Layer* mask_layer() const { return mask_layer_.get(); }
 134
 135   virtual void SetNeedsDisplayRect(const gfx::Rect& dirty_rect);
 136   void SetNeedsDisplay() { SetNeedsDisplayRect(gfx::Rect(bounds())); }
 137
 138   void SetOpacity(float opacity);
 139   float opacity() const { return opacity_; }
 140   bool OpacityIsAnimating() const;
 141   virtual bool OpacityCanAnimateOnImplThread() const;
 142
 143   void SetBlendMode(SkXfermode::Mode blend_mode);
 144   SkXfermode::Mode blend_mode() const { return blend_mode_; }
 145
 146   bool uses_default_blend_mode() const {
 147     return blend_mode_ == SkXfermode::kSrcOver_Mode;
 148   }
 149
 150   // A layer is root for an isolated group when it and all its descendants are
 151   // drawn over a black and fully transparent background, creating an isolated
 152   // group. It should be used along with SetBlendMode(), in order to restrict
 153   // layers within the group to blend with layers outside this group.
 154   void SetIsRootForIsolatedGroup(bool root);
 155   bool is_root_for_isolated_group() const {
 156     return is_root_for_isolated_group_;
 157   }
 158
 159   void SetFilters(const FilterOperations& filters);
 160   const FilterOperations& filters() const { return filters_; }
 161   bool FilterIsAnimating() const;
 162
 163   // Background filters are filters applied to what is behind this layer, when
 164   // they are viewed through non-opaque regions in this layer. They are used
 165   // through the WebLayer interface, and are not exposed to HTML.
 166   void SetBackgroundFilters(const FilterOperations& filters);
 167   const FilterOperations& background_filters() const {
 168     return background_filters_;
 169   }
 170
 171   virtual void SetContentsOpaque(bool opaque);
 172   bool contents_opaque() const { return contents_opaque_; }
 173
 174   void SetPosition(const gfx::PointF& position);
 175   gfx::PointF position() const { return position_; }
 176
 177   // A layer that is a container for fixed position layers cannot be both
 178   // scrollable and have a non-identity transform.
 179   void SetIsContainerForFixedPositionLayers(bool container);
 180   bool IsContainerForFixedPositionLayers() const;
 181
 182   gfx::Vector2dF FixedContainerSizeDelta() const {
 183     return gfx::Vector2dF();
 184   }
 185
 186   void SetPositionConstraint(const LayerPositionConstraint& constraint);
 187   const LayerPositionConstraint& position_constraint() const {
 188     return position_constraint_;
 189   }
 190
 191   void SetTransform(const gfx::Transform& transform);
 192   const gfx::Transform& transform() const { return transform_; }
 193   bool TransformIsAnimating() const;
 194   bool AnimationsPreserveAxisAlignment() const;
 195   bool transform_is_invertible() const { return transform_is_invertible_; }
 196
 197   void SetTransformOrigin(const gfx::Point3F&);
 198   gfx::Point3F transform_origin() const { return transform_origin_; }
 199
 200   void SetScrollParent(Layer* parent);
 201
 202   Layer* scroll_parent() { return scroll_parent_; }
 203   const Layer* scroll_parent() const { return scroll_parent_; }
 204
 205   void AddScrollChild(Layer* child);
 206   void RemoveScrollChild(Layer* child);
 207
 208   std::set<Layer*>* scroll_children() { return scroll_children_.get(); }
 209   const std::set<Layer*>* scroll_children() const {
 210     return scroll_children_.get();
 211   }
 212
 213   void SetClipParent(Layer* ancestor);
 214
 215   Layer* clip_parent() { return clip_parent_; }
 216   const Layer* clip_parent() const {
 217     return clip_parent_;
 218   }
 219
 220   void AddClipChild(Layer* child);
 221   void RemoveClipChild(Layer* child);
 222
 223   std::set<Layer*>* clip_children() { return clip_children_.get(); }
 224   const std::set<Layer*>* clip_children() const {
 225     return clip_children_.get();
 226   }
 227
 228   DrawProperties<Layer>& draw_properties() { return draw_properties_; }
 229   const DrawProperties<Layer>& draw_properties() const {
 230     return draw_properties_;
 231   }
 232
 233   // The following are shortcut accessors to get various information from
 234   // draw_properties_
 235   const gfx::Transform& draw_transform() const {
 236     return draw_properties_.target_space_transform;
 237   }
 238   const gfx::Transform& screen_space_transform() const {
 239     return draw_properties_.screen_space_transform;
 240   }
 241   float draw_opacity() const { return draw_properties_.opacity; }
 242   bool draw_opacity_is_animating() const {
 243     return draw_properties_.opacity_is_animating;
 244   }
 245   bool draw_transform_is_animating() const {
 246     return draw_properties_.target_space_transform_is_animating;
 247   }
 248   bool screen_space_transform_is_animating() const {
 249     return draw_properties_.screen_space_transform_is_animating;
 250   }
 251   bool screen_space_opacity_is_animating() const {
 252     return draw_properties_.screen_space_opacity_is_animating;
 253   }
 254   bool is_clipped() const { return draw_properties_.is_clipped; }
 255   gfx::Rect clip_rect() const { return draw_properties_.clip_rect; }
 256   gfx::Rect drawable_content_rect() const {
 257     return draw_properties_.drawable_content_rect;
 258   }
 259   gfx::Rect visible_content_rect() const {
 260     return draw_properties_.visible_content_rect;
 261   }
 262   Layer* render_target() {
 263     DCHECK(!draw_properties_.render_target ||
 264            draw_properties_.render_target->render_surface());
 265     return draw_properties_.render_target;
 266   }
 267   const Layer* render_target() const {
 268     DCHECK(!draw_properties_.render_target ||
 269            draw_properties_.render_target->render_surface());
 270     return draw_properties_.render_target;
 271   }
 272   int num_unclipped_descendants() const {
 273     return draw_properties_.num_unclipped_descendants;
 274   }
 275
 276   RenderSurface* render_surface() const { return render_surface_.get(); }
 277   void SetScrollOffset(const gfx::ScrollOffset& scroll_offset);
 278   void SetScrollCompensationAdjustment(
 279       const gfx::Vector2dF& scroll_compensation_adjustment);
 280   gfx::Vector2dF ScrollCompensationAdjustment() const;
 281
 282   gfx::ScrollOffset scroll_offset() const { return scroll_offset_; }
 283   void SetScrollOffsetFromImplSide(const gfx::ScrollOffset& scroll_offset);
 284
 285   void SetScrollClipLayerId(int clip_layer_id);
 286   bool scrollable() const { return scroll_clip_layer_id_ != INVALID_ID; }
 287
 288   void SetUserScrollable(bool horizontal, bool vertical);
 289   bool user_scrollable_horizontal() const {
 290     return user_scrollable_horizontal_;
 291   }
 292   bool user_scrollable_vertical() const { return user_scrollable_vertical_; }
 293
 294   void SetShouldScrollOnMainThread(bool should_scroll_on_main_thread);
 295   bool should_scroll_on_main_thread() const {
 296     return should_scroll_on_main_thread_;
 297   }
 298
 299   void SetHaveWheelEventHandlers(bool have_wheel_event_handlers);
 300   bool have_wheel_event_handlers() const { return have_wheel_event_handlers_; }
 301
 302   void SetHaveScrollEventHandlers(bool have_scroll_event_handlers);
 303   bool have_scroll_event_handlers() const {
 304     return have_scroll_event_handlers_;
 305   }
 306
 307   void SetNonFastScrollableRegion(const Region& non_fast_scrollable_region);
 308   const Region& non_fast_scrollable_region() const {
 309     return non_fast_scrollable_region_;
 310   }
 311
 312   void SetTouchEventHandlerRegion(const Region& touch_event_handler_region);
 313   const Region& touch_event_handler_region() const {
 314     return touch_event_handler_region_;
 315   }
 316
 317   void SetScrollBlocksOn(ScrollBlocksOn scroll_blocks_on);
 318   ScrollBlocksOn scroll_blocks_on() const { return scroll_blocks_on_; }
 319
 320   void set_did_scroll_callback(const base::Closure& callback) {
 321     did_scroll_callback_ = callback;
 322   }
 323
 324   void SetDrawCheckerboardForMissingTiles(bool checkerboard);
 325   bool draw_checkerboard_for_missing_tiles() const {
 326     return draw_checkerboard_for_missing_tiles_;
 327   }
 328
 329   void SetForceRenderSurface(bool force_render_surface);
 330   bool force_render_surface() const { return force_render_surface_; }
 331
 332   gfx::Vector2dF ScrollDelta() const { return gfx::Vector2dF(); }
 333   gfx::ScrollOffset CurrentScrollOffset() const { return scroll_offset_; }
 334
 335   void SetDoubleSided(bool double_sided);
 336   bool double_sided() const { return double_sided_; }
 337
 338   void SetShouldFlattenTransform(bool flatten);
 339   bool should_flatten_transform() const { return should_flatten_transform_; }
 340
 341   bool Is3dSorted() const { return sorting_context_id_ != 0; }
 342
 343   void set_use_parent_backface_visibility(bool use) {
 344     use_parent_backface_visibility_ = use;
 345   }
 346   bool use_parent_backface_visibility() const {
 347     return use_parent_backface_visibility_;
 348   }
 349
 350   virtual void SetLayerTreeHost(LayerTreeHost* host);
 351
 352   virtual bool HasDelegatedContent() const;
 353   bool HasContributingDelegatedRenderPasses() const { return false; }
 354
 355   void SetIsDrawable(bool is_drawable);
 356
 357   void SetHideLayerAndSubtree(bool hide);
 358   bool hide_layer_and_subtree() const { return hide_layer_and_subtree_; }
 359
 360   void SetReplicaLayer(Layer* layer);
 361   Layer* replica_layer() { return replica_layer_.get(); }
 362   const Layer* replica_layer() const { return replica_layer_.get(); }
 363
 364   bool has_mask() const { return !!mask_layer_.get(); }
 365   bool has_replica() const { return !!replica_layer_.get(); }
 366   bool replica_has_mask() const {
 367     return replica_layer_.get() &&
 368            (mask_layer_.get() || replica_layer_->mask_layer_.get());
 369   }
 370
 371   int NumDescendantsThatDrawContent() const;
 372
 373   // This is only virtual for tests.
 374   // TODO(awoloszyn): Remove this once we no longer need it for tests
 375   virtual bool DrawsContent() const;
 376
 377   // This methods typically need to be overwritten by derived classes.
 378   virtual void SavePaintProperties();
 379   // Returns true iff any resources were updated that need to be committed.
 380   virtual bool Update(ResourceUpdateQueue* queue,
 381                       const OcclusionTracker<Layer>* occlusion);
 382   virtual bool NeedMoreUpdates();
 383   virtual void SetIsMask(bool is_mask) {}
 384   virtual void ReduceMemoryUsage() {}
 385   virtual void OnOutputSurfaceCreated() {}
 386   virtual bool IsSuitableForGpuRasterization() const;
 387
 388   virtual scoped_refptr<base::trace_event::ConvertableToTraceFormat>
 389   TakeDebugInfo();
 390
 391   void SetLayerClient(LayerClient* client) { client_ = client; }
 392
 393   virtual void PushPropertiesTo(LayerImpl* layer);
 394
 395   void CreateRenderSurface();
 396   void ClearRenderSurface();
 397
 398   void ClearRenderSurfaceLayerList();
 399
 400   // The contents scale converts from logical, non-page-scaled pixels to target
 401   // pixels. The contents scale is 1 for the root layer as it is already in
 402   // physical pixels. By default contents scale is forced to be 1 except for
 403   // subclasses of ContentsScalingLayer.
 404   float contents_scale_x() const { return draw_properties_.contents_scale_x; }
 405   float contents_scale_y() const { return draw_properties_.contents_scale_y; }
 406   gfx::Size content_bounds() const { return draw_properties_.content_bounds; }
 407
 408   virtual void CalculateContentsScale(float ideal_contents_scale,
 409                                       float* contents_scale_x,
 410                                       float* contents_scale_y,
 411                                       gfx::Size* content_bounds);
 412
 413   LayerTreeHost* layer_tree_host() { return layer_tree_host_; }
 414   const LayerTreeHost* layer_tree_host() const { return layer_tree_host_; }
 415
 416   // Set the priority of all desired textures in this layer.
 417   virtual void SetTexturePriorities(const PriorityCalculator& priority_calc) {}
 418
 419   bool AddAnimation(scoped_ptr<Animation> animation);
 420   void PauseAnimation(int animation_id, double time_offset);
 421   void RemoveAnimation(int animation_id);
 422   void RemoveAnimation(int animation_id, Animation::TargetProperty property);
 423
 424   LayerAnimationController* layer_animation_controller() {
 425     return layer_animation_controller_.get();
 426   }
 427   void SetLayerAnimationControllerForTest(
 428       scoped_refptr<LayerAnimationController> controller);
 429
 430   void set_layer_animation_delegate(AnimationDelegate* delegate) {
 431     DCHECK(layer_animation_controller_);
 432     layer_animation_controller_->set_layer_animation_delegate(delegate);
 433   }
 434
 435   bool HasActiveAnimation() const;
 436   void RegisterForAnimations(AnimationRegistrar* registrar);
 437
 438   void AddLayerAnimationEventObserver(
 439       LayerAnimationEventObserver* animation_observer);
 440   void RemoveLayerAnimationEventObserver(
 441       LayerAnimationEventObserver* animation_observer);
 442
 443   virtual SimpleEnclosedRegion VisibleContentOpaqueRegion() const;
 444
 445   virtual ScrollbarLayerInterface* ToScrollbarLayer();
 446
 447   gfx::Rect LayerRectToContentRect(const gfx::Rect& layer_rect) const;
 448
 449   virtual skia::RefPtr<SkPicture> GetPicture() const;
 450
 451   // Constructs a LayerImpl of the correct runtime type for this Layer type.
 452   virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl);
 453
 454   bool NeedsDisplayForTesting() const { return !update_rect_.IsEmpty(); }
 455   void ResetNeedsDisplayForTesting() { update_rect_ = gfx::Rect(); }
 456
 457   RenderingStatsInstrumentation* rendering_stats_instrumentation() const;
 458
 459   const PaintProperties& paint_properties() const {
 460     return paint_properties_;
 461   }
 462
 463   // The scale at which contents should be rastered, to match the scale at
 464   // which they will drawn to the screen. This scale is a component of the
 465   // contents scale but does not include page/device scale factors.
 466   // TODO(danakj): This goes away when TiledLayer goes away.
 467   void set_raster_scale(float scale) { raster_scale_ = scale; }
 468   float raster_scale() const { return raster_scale_; }
 469   bool raster_scale_is_unknown() const { return raster_scale_ == 0.f; }
 470
 471   void SetNeedsPushProperties();
 472   bool needs_push_properties() const { return needs_push_properties_; }
 473   bool descendant_needs_push_properties() const {
 474     return num_dependents_need_push_properties_ > 0;
 475   }
 476   void reset_needs_push_properties_for_testing() {
 477     needs_push_properties_ = false;
 478   }
 479
 480   virtual void RunMicroBenchmark(MicroBenchmark* benchmark);
 481
 482   void Set3dSortingContextId(int id);
 483   int sorting_context_id() const { return sorting_context_id_; }
 484
 485   void set_property_tree_sequence_number(int sequence_number) {
 486     property_tree_sequence_number_ = sequence_number;
 487   }
 488
 489   void SetTransformTreeIndex(int index);
 490   int transform_tree_index() const;
 491
 492   void SetClipTreeIndex(int index);
 493   int clip_tree_index() const;
 494
 495   void SetOpacityTreeIndex(int index);
 496   int opacity_tree_index() const;
 497
 498   void set_offset_to_transform_parent(gfx::Vector2dF offset) {
 499     if (offset_to_transform_parent_ == offset)
 500       return;
 501     offset_to_transform_parent_ = offset;
 502     SetNeedsPushProperties();
 503   }
 504   gfx::Vector2dF offset_to_transform_parent() const {
 505     return offset_to_transform_parent_;
 506   }
 507
 508   // TODO(vollick): Once we transition to transform and clip trees, rename these
 509   // functions and related values.  The "from property trees" functions below
 510   // use the transform and clip trees.  Eventually, we will use these functions
 511   // to compute the official values, but these functions are retained for
 512   // testing purposes until we've migrated.
 513
 514   const gfx::Rect& visible_rect_from_property_trees() const {
 515     return visible_rect_from_property_trees_;
 516   }
 517   void set_visible_rect_from_property_trees(const gfx::Rect& rect) {
 518     // No push properties here, as this acts like a draw property.
 519     visible_rect_from_property_trees_ = rect;
 520   }
 521
 522   void set_should_flatten_transform_from_property_tree(bool should_flatten) {
 523     if (should_flatten_transform_from_property_tree_ == should_flatten)
 524       return;
 525     should_flatten_transform_from_property_tree_ = should_flatten;
 526     SetNeedsPushProperties();
 527   }
 528   bool should_flatten_transform_from_property_tree() const {
 529     return should_flatten_transform_from_property_tree_;
 530   }
 531
 532   // TODO(vollick): These values are temporary and will be removed as soon as
 533   // render surface determinations are moved out of CDP. They only exist because
 534   // certain logic depends on whether or not a layer would render to a separate
 535   // surface, but CDP destroys surfaces and targets it doesn't need, so without
 536   // this boolean, this is impossible to determine after the fact without
 537   // wastefully recomputing it. This is public for the time being so that it can
 538   // be accessed from CDP.
 539   bool has_render_surface() const {
 540     return has_render_surface_;
 541   }
 542
 543   // Sets new frame timing requests for this layer.
 544   void SetFrameTimingRequests(const std::vector<FrameTimingRequest>& requests);
 545
 546   // Accessor for unit tests
 547   const std::vector<FrameTimingRequest>& FrameTimingRequests() const {
 548     return frame_timing_requests_;
 549   }
 550
 551   void DidBeginTracing();
 552   void set_num_layer_or_descandant_with_copy_request(
 553       int num_layer_or_descendants_with_copy_request) {
 554     num_layer_or_descendants_with_copy_request_ =
 555         num_layer_or_descendants_with_copy_request;
 556   }
 557
 558   void set_num_layer_or_descandant_with_input_handler(
 559       int num_layer_or_descendants_with_input_handler) {
 560     num_layer_or_descendants_with_input_handler_ =
 561         num_layer_or_descendants_with_input_handler;
 562   }
 563
 564   int num_layer_or_descendants_with_input_handler() {
 565     return num_layer_or_descendants_with_input_handler_;
 566   }
 567
 568   void set_num_children_with_scroll_parent(
 569       int num_children_with_scroll_parent) {
 570     num_children_with_scroll_parent_ = num_children_with_scroll_parent;
 571   }
 572
 573   int num_children_with_scroll_parent() {
 574     return num_children_with_scroll_parent_;
 575   }
 576
 577   void set_visited(bool visited);
 578   bool visited();
 579   void set_layer_or_descendant_is_drawn(bool layer_or_descendant_is_drawn);
 580   bool layer_or_descendant_is_drawn();
 581   void set_sorted_for_recursion(bool sorted_for_recursion);
 582   bool sorted_for_recursion();
 583
 584  protected:
 585   friend class LayerImpl;
 586   friend class TreeSynchronizer;
 587   ~Layer() override;
 588
 589   explicit Layer(const LayerSettings& settings);
 590
 591   // These SetNeeds functions are in order of severity of update:
 592   //
 593   // Called when this layer has been modified in some way, but isn't sure
 594   // that it needs a commit yet.  It needs CalcDrawProperties and UpdateLayers
 595   // before it knows whether or not a commit is required.
 596   void SetNeedsUpdate();
 597   // Called when a property has been modified in a way that the layer
 598   // knows immediately that a commit is required.  This implies SetNeedsUpdate
 599   // as well as SetNeedsPushProperties to push that property.
 600   void SetNeedsCommit();
 601   // This is identical to SetNeedsCommit, but the former requests a rebuild of
 602   // the property trees.
 603   void SetNeedsCommitNoRebuild();
 604   // Called when there's been a change in layer structure.  Implies both
 605   // SetNeedsUpdate and SetNeedsCommit, but not SetNeedsPushProperties.
 606   void SetNeedsFullTreeSync();
 607
 608   // Called when the next commit should wait until the pending tree is activated
 609   // before finishing the commit and unblocking the main thread. Used to ensure
 610   // unused resources on the impl thread are returned before commit completes.
 611   void SetNextCommitWaitsForActivation();
 612
 613   // Will recalculate whether the layer draws content and set draws_content_
 614   // appropriately.
 615   void UpdateDrawsContent(bool has_drawable_content);
 616   virtual bool HasDrawableContent() const;
 617
 618   // Called when the layer's number of drawable descendants changes.
 619   void AddDrawableDescendants(int num);
 620
 621   void AddDependentNeedsPushProperties();
 622   void RemoveDependentNeedsPushProperties();
 623   bool parent_should_know_need_push_properties() const {
 624     return needs_push_properties() || descendant_needs_push_properties();
 625   }
 626
 627   bool IsPropertyChangeAllowed() const;
 628
 629   void reset_raster_scale_to_unknown() { raster_scale_ = 0.f; }
 630
 631   // This flag is set when the layer needs to push properties to the impl
 632   // side.
 633   bool needs_push_properties_;
 634
 635   // The number of direct children or dependent layers that need to be recursed
 636   // to in order for them or a descendent of them to push properties to the impl
 637   // side.
 638   int num_dependents_need_push_properties_;
 639
 640   // Tracks whether this layer may have changed stacking order with its
 641   // siblings.
 642   bool stacking_order_changed_;
 643
 644   // The update rect is the region of the compositor resource that was
 645   // actually updated by the compositor. For layers that may do updating
 646   // outside the compositor's control (i.e. plugin layers), this information
 647   // is not available and the update rect will remain empty.
 648   // Note this rect is in layer space (not content space).
 649   gfx::Rect update_rect_;
 650
 651   scoped_refptr<Layer> mask_layer_;
 652
 653   int layer_id_;
 654
 655   // When true, the layer is about to perform an update. Any commit requests
 656   // will be handled implicitly after the update completes.
 657   bool ignore_set_needs_commit_;
 658
 659   // Layers that share a sorting context id will be sorted together in 3d
 660   // space.  0 is a special value that means this layer will not be sorted and
 661   // will be drawn in paint order.
 662   int sorting_context_id_;
 663
 664  private:
 665   friend class base::RefCounted<Layer>;
 666   friend class LayerTreeHostCommon;
 667   void SetParent(Layer* layer);
 668   bool DescendantIsFixedToContainerLayer() const;
 669
 670   // This should only be called during BeginMainFrame since it does not
 671   // trigger a Commit.
 672   void SetHasRenderSurface(bool has_render_surface);
 673
 674   // Returns the index of the child or -1 if not found.
 675   int IndexOfChild(const Layer* reference);
 676
 677   // This should only be called from RemoveFromParent().
 678   void RemoveChildOrDependent(Layer* child);
 679
 680   // LayerAnimationValueProvider implementation.
 681   gfx::ScrollOffset ScrollOffsetForAnimation() const override;
 682
 683   // LayerAnimationValueObserver implementation.
 684   void OnFilterAnimated(const FilterOperations& filters) override;
 685   void OnOpacityAnimated(float opacity) override;
 686   void OnTransformAnimated(const gfx::Transform& transform) override;
 687   void OnScrollOffsetAnimated(const gfx::ScrollOffset& scroll_offset) override;
 688   void OnAnimationWaitingForDeletion() override;
 689   bool IsActive() const override;
 690
 691   // If this layer has a scroll parent, it removes |this| from its list of
 692   // scroll children.
 693   void RemoveFromScrollTree();
 694
 695   // If this layer has a clip parent, it removes |this| from its list of clip
 696   // children.
 697   void RemoveFromClipTree();
 698
 699   void UpdateNumCopyRequestsForSubtree(bool add);
 700   void UpdateNumInputHandlersForSubtree(bool add);
 701
 702   LayerList children_;
 703   Layer* parent_;
 704
 705   // Layer instances have a weak pointer to their LayerTreeHost.
 706   // This pointer value is nil when a Layer is not in a tree and is
 707   // updated via SetLayerTreeHost() if a layer moves between trees.
 708   LayerTreeHost* layer_tree_host_;
 709
 710   scoped_refptr<LayerAnimationController> layer_animation_controller_;
 711
 712   // Layer properties.
 713   gfx::Size bounds_;
 714
 715   gfx::ScrollOffset scroll_offset_;
 716   gfx::Vector2dF scroll_compensation_adjustment_;
 717   // This variable indicates which ancestor layer (if any) whose size,
 718   // transformed relative to this layer, defines the maximum scroll offset for
 719   // this layer.
 720   int scroll_clip_layer_id_;
 721   int num_descendants_that_draw_content_;
 722   int transform_tree_index_;
 723   int opacity_tree_index_;
 724   int clip_tree_index_;
 725   int property_tree_sequence_number_;
 726   int num_layer_or_descendants_with_copy_request_;
 727   int num_layer_or_descendants_with_input_handler_;
 728   int num_children_with_scroll_parent_;
 729   gfx::Vector2dF offset_to_transform_parent_;
 730   bool should_flatten_transform_from_property_tree_ : 1;
 731   bool should_scroll_on_main_thread_ : 1;
 732   bool have_wheel_event_handlers_ : 1;
 733   bool have_scroll_event_handlers_ : 1;
 734   bool user_scrollable_horizontal_ : 1;
 735   bool user_scrollable_vertical_ : 1;
 736   bool is_root_for_isolated_group_ : 1;
 737   bool is_container_for_fixed_position_layers_ : 1;
 738   bool is_drawable_ : 1;
 739   bool draws_content_ : 1;
 740   bool hide_layer_and_subtree_ : 1;
 741   bool masks_to_bounds_ : 1;
 742   bool contents_opaque_ : 1;
 743   bool double_sided_ : 1;
 744   bool should_flatten_transform_ : 1;
 745   bool use_parent_backface_visibility_ : 1;
 746   bool draw_checkerboard_for_missing_tiles_ : 1;
 747   bool force_render_surface_ : 1;
 748   bool transform_is_invertible_ : 1;
 749   bool has_render_surface_ : 1;
 750   ScrollBlocksOn scroll_blocks_on_ : 3;
 751   Region non_fast_scrollable_region_;
 752   Region touch_event_handler_region_;
 753   gfx::PointF position_;
 754   SkColor background_color_;
 755   float opacity_;
 756   SkXfermode::Mode blend_mode_;
 757   FilterOperations filters_;
 758   FilterOperations background_filters_;
 759   LayerPositionConstraint position_constraint_;
 760   Layer* scroll_parent_;
 761   scoped_ptr<std::set<Layer*>> scroll_children_;
 762
 763   // The following three variables are tracker variables. They are bools
 764   // wrapped inside an integer variable. If true, their value equals the
 765   // LayerTreeHost's meta_information_sequence_number. This wrapping of bools
 766   // inside ints is done to avoid a layer tree treewalk to reset their values.
 767   int layer_or_descendant_is_drawn_tracker_;
 768   int sorted_for_recursion_tracker_;
 769   int visited_tracker_;
 770
 771   Layer* clip_parent_;
 772   scoped_ptr<std::set<Layer*>> clip_children_;
 773
 774   gfx::Transform transform_;
 775   gfx::Point3F transform_origin_;
 776
 777   // Replica layer used for reflections.
 778   scoped_refptr<Layer> replica_layer_;
 779
 780   // Transient properties.
 781   float raster_scale_;
 782
 783   LayerClient* client_;
 784
 785   ScopedPtrVector<CopyOutputRequest> copy_requests_;
 786
 787   base::Closure did_scroll_callback_;
 788
 789   DrawProperties<Layer> draw_properties_;
 790
 791   PaintProperties paint_properties_;
 792   // TODO(awoloszyn): This is redundant with has_render_surface_,
 793   // and should get removed once it is no longer needed on main thread.
 794   scoped_ptr<RenderSurface> render_surface_;
 795
 796   gfx::Rect visible_rect_from_property_trees_;
 797
 798   std::vector<FrameTimingRequest> frame_timing_requests_;
 799   bool frame_timing_requests_dirty_;
 800
 801   DISALLOW_COPY_AND_ASSIGN(Layer);
 802 };
 803
 804 }  // namespace cc
 805
 806 #endif  // CC_LAYERS_LAYER_H_