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