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      1 // Copyright 2011 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #ifndef CC_LAYERS_LAYER_IMPL_H_
      6 #define CC_LAYERS_LAYER_IMPL_H_
      7 
      8 #include <set>
      9 #include <string>
     10 
     11 #include "base/logging.h"
     12 #include "base/memory/scoped_ptr.h"
     13 #include "base/values.h"
     14 #include "cc/animation/layer_animation_controller.h"
     15 #include "cc/animation/layer_animation_value_observer.h"
     16 #include "cc/animation/layer_animation_value_provider.h"
     17 #include "cc/base/cc_export.h"
     18 #include "cc/base/region.h"
     19 #include "cc/base/scoped_ptr_vector.h"
     20 #include "cc/input/input_handler.h"
     21 #include "cc/layers/compositing_reasons.h"
     22 #include "cc/layers/draw_properties.h"
     23 #include "cc/layers/layer_lists.h"
     24 #include "cc/layers/layer_position_constraint.h"
     25 #include "cc/layers/render_surface_impl.h"
     26 #include "cc/output/filter_operations.h"
     27 #include "cc/quads/render_pass.h"
     28 #include "cc/quads/shared_quad_state.h"
     29 #include "cc/resources/resource_provider.h"
     30 #include "skia/ext/refptr.h"
     31 #include "third_party/skia/include/core/SkColor.h"
     32 #include "third_party/skia/include/core/SkImageFilter.h"
     33 #include "third_party/skia/include/core/SkPicture.h"
     34 #include "ui/gfx/rect.h"
     35 #include "ui/gfx/rect_f.h"
     36 #include "ui/gfx/transform.h"
     37 
     38 namespace base {
     39 namespace debug {
     40 class ConvertableToTraceFormat;
     41 }
     42 
     43 class DictionaryValue;
     44 }
     45 
     46 namespace cc {
     47 
     48 class LayerTreeHostImpl;
     49 class LayerTreeImpl;
     50 class MicroBenchmarkImpl;
     51 class QuadSink;
     52 class Renderer;
     53 class ScrollbarAnimationController;
     54 class ScrollbarLayerImplBase;
     55 
     56 struct AppendQuadsData;
     57 
     58 enum DrawMode {
     59   DRAW_MODE_NONE,
     60   DRAW_MODE_HARDWARE,
     61   DRAW_MODE_SOFTWARE,
     62   DRAW_MODE_RESOURCELESS_SOFTWARE
     63 };
     64 
     65 class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
     66                             public LayerAnimationValueProvider {
     67  public:
     68   typedef LayerImplList RenderSurfaceListType;
     69   typedef LayerImplList LayerListType;
     70   typedef RenderSurfaceImpl RenderSurfaceType;
     71 
     72   static scoped_ptr<LayerImpl> Create(LayerTreeImpl* tree_impl, int id) {
     73     return make_scoped_ptr(new LayerImpl(tree_impl, id));
     74   }
     75 
     76   virtual ~LayerImpl();
     77 
     78   int id() const { return layer_id_; }
     79 
     80   // LayerAnimationValueProvider implementation.
     81   virtual gfx::Vector2dF ScrollOffsetForAnimation() const OVERRIDE;
     82 
     83   // LayerAnimationValueObserver implementation.
     84   virtual void OnFilterAnimated(const FilterOperations& filters) OVERRIDE;
     85   virtual void OnOpacityAnimated(float opacity) OVERRIDE;
     86   virtual void OnTransformAnimated(const gfx::Transform& transform) OVERRIDE;
     87   virtual void OnScrollOffsetAnimated(gfx::Vector2dF scroll_offset) OVERRIDE;
     88   virtual void OnAnimationWaitingForDeletion() OVERRIDE;
     89   virtual bool IsActive() const OVERRIDE;
     90 
     91   // Tree structure.
     92   LayerImpl* parent() { return parent_; }
     93   const LayerImpl* parent() const { return parent_; }
     94   const OwnedLayerImplList& children() const { return children_; }
     95   OwnedLayerImplList& children() { return children_; }
     96   LayerImpl* child_at(size_t index) const { return children_[index]; }
     97   void AddChild(scoped_ptr<LayerImpl> child);
     98   scoped_ptr<LayerImpl> RemoveChild(LayerImpl* child);
     99   void set_parent(LayerImpl* parent) { parent_ = parent; }
    100   // Warning: This does not preserve tree structure invariants.
    101   void ClearChildList();
    102 
    103   bool HasAncestor(const LayerImpl* ancestor) const;
    104 
    105   void SetScrollParent(LayerImpl* parent);
    106 
    107   LayerImpl* scroll_parent() { return scroll_parent_; }
    108   const LayerImpl* scroll_parent() const { return scroll_parent_; }
    109 
    110   void SetScrollChildren(std::set<LayerImpl*>* children);
    111   void RemoveScrollChild(LayerImpl* child);
    112 
    113   std::set<LayerImpl*>* scroll_children() { return scroll_children_.get(); }
    114   const std::set<LayerImpl*>* scroll_children() const {
    115     return scroll_children_.get();
    116   }
    117 
    118   void SetClipParent(LayerImpl* ancestor);
    119 
    120   LayerImpl* clip_parent() {
    121     return clip_parent_;
    122   }
    123   const LayerImpl* clip_parent() const {
    124     return clip_parent_;
    125   }
    126 
    127   void SetClipChildren(std::set<LayerImpl*>* children);
    128   void RemoveClipChild(LayerImpl* child);
    129 
    130   std::set<LayerImpl*>* clip_children() { return clip_children_.get(); }
    131   const std::set<LayerImpl*>* clip_children() const {
    132     return clip_children_.get();
    133   }
    134 
    135   void PassCopyRequests(ScopedPtrVector<CopyOutputRequest>* requests);
    136   void TakeCopyRequestsAndTransformToTarget(
    137       ScopedPtrVector<CopyOutputRequest>* request);
    138   bool HasCopyRequest() const { return !copy_requests_.empty(); }
    139 
    140   void SetMaskLayer(scoped_ptr<LayerImpl> mask_layer);
    141   LayerImpl* mask_layer() { return mask_layer_.get(); }
    142   const LayerImpl* mask_layer() const { return mask_layer_.get(); }
    143   scoped_ptr<LayerImpl> TakeMaskLayer();
    144 
    145   void SetReplicaLayer(scoped_ptr<LayerImpl> replica_layer);
    146   LayerImpl* replica_layer() { return replica_layer_.get(); }
    147   const LayerImpl* replica_layer() const { return replica_layer_.get(); }
    148   scoped_ptr<LayerImpl> TakeReplicaLayer();
    149 
    150   bool has_mask() const { return mask_layer_; }
    151   bool has_replica() const { return replica_layer_; }
    152   bool replica_has_mask() const {
    153     return replica_layer_ && (mask_layer_ || replica_layer_->mask_layer_);
    154   }
    155 
    156   LayerTreeImpl* layer_tree_impl() const { return layer_tree_impl_; }
    157 
    158   scoped_ptr<SharedQuadState> CreateSharedQuadState() const;
    159   // WillDraw must be called before AppendQuads. If WillDraw returns false,
    160   // AppendQuads and DidDraw will not be called. If WillDraw returns true,
    161   // DidDraw is guaranteed to be called before another WillDraw or before
    162   // the layer is destroyed. To enforce this, any class that overrides
    163   // WillDraw/DidDraw must call the base class version only if WillDraw
    164   // returns true.
    165   virtual bool WillDraw(DrawMode draw_mode,
    166                         ResourceProvider* resource_provider);
    167   virtual void AppendQuads(QuadSink* quad_sink,
    168                            AppendQuadsData* append_quads_data) {}
    169   virtual void DidDraw(ResourceProvider* resource_provider);
    170 
    171   virtual ResourceProvider::ResourceId ContentsResourceId() const;
    172 
    173   virtual bool HasDelegatedContent() const;
    174   virtual bool HasContributingDelegatedRenderPasses() const;
    175   virtual RenderPass::Id FirstContributingRenderPassId() const;
    176   virtual RenderPass::Id NextContributingRenderPassId(RenderPass::Id id) const;
    177 
    178   virtual void UpdateTilePriorities() {}
    179 
    180   virtual ScrollbarLayerImplBase* ToScrollbarLayer();
    181 
    182   // Returns true if this layer has content to draw.
    183   void SetDrawsContent(bool draws_content);
    184   bool DrawsContent() const { return draws_content_; }
    185 
    186   void SetHideLayerAndSubtree(bool hide);
    187   bool hide_layer_and_subtree() const { return hide_layer_and_subtree_; }
    188 
    189   bool force_render_surface() const { return force_render_surface_; }
    190   void SetForceRenderSurface(bool force) { force_render_surface_ = force; }
    191 
    192   void SetAnchorPoint(gfx::PointF anchor_point);
    193   gfx::PointF anchor_point() const { return anchor_point_; }
    194 
    195   void SetAnchorPointZ(float anchor_point_z);
    196   float anchor_point_z() const { return anchor_point_z_; }
    197 
    198   void SetBackgroundColor(SkColor background_color);
    199   SkColor background_color() const { return background_color_; }
    200   // If contents_opaque(), return an opaque color else return a
    201   // non-opaque color.  Tries to return background_color(), if possible.
    202   SkColor SafeOpaqueBackgroundColor() const;
    203 
    204   void SetFilters(const FilterOperations& filters);
    205   const FilterOperations& filters() const { return filters_; }
    206   bool FilterIsAnimating() const;
    207   bool FilterIsAnimatingOnImplOnly() const;
    208 
    209   void SetBackgroundFilters(const FilterOperations& filters);
    210   const FilterOperations& background_filters() const {
    211     return background_filters_;
    212   }
    213 
    214   void SetMasksToBounds(bool masks_to_bounds);
    215   bool masks_to_bounds() const { return masks_to_bounds_; }
    216 
    217   void SetContentsOpaque(bool opaque);
    218   bool contents_opaque() const { return contents_opaque_; }
    219 
    220   void SetOpacity(float opacity);
    221   float opacity() const { return opacity_; }
    222   bool OpacityIsAnimating() const;
    223   bool OpacityIsAnimatingOnImplOnly() const;
    224 
    225   void SetBlendMode(SkXfermode::Mode);
    226   SkXfermode::Mode blend_mode() const { return blend_mode_; }
    227   bool uses_default_blend_mode() const {
    228     return blend_mode_ == SkXfermode::kSrcOver_Mode;
    229   }
    230 
    231   void SetIsRootForIsolatedGroup(bool root);
    232   bool is_root_for_isolated_group() const {
    233     return is_root_for_isolated_group_;
    234   }
    235 
    236   void SetPosition(gfx::PointF position);
    237   gfx::PointF position() const { return position_; }
    238 
    239   void SetIsContainerForFixedPositionLayers(bool container) {
    240     is_container_for_fixed_position_layers_ = container;
    241   }
    242   // This is a non-trivial function in Layer.
    243   bool IsContainerForFixedPositionLayers() const {
    244     return is_container_for_fixed_position_layers_;
    245   }
    246 
    247   void SetFixedContainerSizeDelta(gfx::Vector2dF delta) {
    248     fixed_container_size_delta_ = delta;
    249   }
    250   gfx::Vector2dF fixed_container_size_delta() const {
    251     return fixed_container_size_delta_;
    252   }
    253 
    254   void SetPositionConstraint(const LayerPositionConstraint& constraint) {
    255     position_constraint_ = constraint;
    256   }
    257   const LayerPositionConstraint& position_constraint() const {
    258     return position_constraint_;
    259   }
    260 
    261   void SetPreserves3d(bool preserves_3d);
    262   bool preserves_3d() const { return preserves_3d_; }
    263 
    264   void SetUseParentBackfaceVisibility(bool use) {
    265     use_parent_backface_visibility_ = use;
    266   }
    267   bool use_parent_backface_visibility() const {
    268     return use_parent_backface_visibility_;
    269   }
    270 
    271   void SetSublayerTransform(const gfx::Transform& sublayer_transform);
    272   const gfx::Transform& sublayer_transform() const {
    273     return sublayer_transform_;
    274   }
    275 
    276   // Debug layer name.
    277   void SetDebugName(const std::string& debug_name) { debug_name_ = debug_name; }
    278   std::string debug_name() const { return debug_name_; }
    279 
    280   void SetCompositingReasons(CompositingReasons reasons) {
    281       compositing_reasons_ = reasons;
    282   }
    283 
    284   CompositingReasons compositing_reasons() const {
    285       return compositing_reasons_;
    286   }
    287 
    288   bool ShowDebugBorders() const;
    289 
    290   // These invalidate the host's render surface layer list.  The caller
    291   // is responsible for calling set_needs_update_draw_properties on the tree
    292   // so that its list can be recreated.
    293   void CreateRenderSurface();
    294   void ClearRenderSurface();
    295 
    296   DrawProperties<LayerImpl>& draw_properties() {
    297     return draw_properties_;
    298   }
    299   const DrawProperties<LayerImpl>& draw_properties() const {
    300     return draw_properties_;
    301   }
    302 
    303   // The following are shortcut accessors to get various information from
    304   // draw_properties_
    305   const gfx::Transform& draw_transform() const {
    306     return draw_properties_.target_space_transform;
    307   }
    308   const gfx::Transform& screen_space_transform() const {
    309     return draw_properties_.screen_space_transform;
    310   }
    311   float draw_opacity() const { return draw_properties_.opacity; }
    312   bool draw_opacity_is_animating() const {
    313     return draw_properties_.opacity_is_animating;
    314   }
    315   bool draw_transform_is_animating() const {
    316     return draw_properties_.target_space_transform_is_animating;
    317   }
    318   bool screen_space_transform_is_animating() const {
    319     return draw_properties_.screen_space_transform_is_animating;
    320   }
    321   bool screen_space_opacity_is_animating() const {
    322     return draw_properties_.screen_space_opacity_is_animating;
    323   }
    324   bool can_use_lcd_text() const { return draw_properties_.can_use_lcd_text; }
    325   bool is_clipped() const { return draw_properties_.is_clipped; }
    326   gfx::Rect clip_rect() const { return draw_properties_.clip_rect; }
    327   gfx::Rect drawable_content_rect() const {
    328     return draw_properties_.drawable_content_rect;
    329   }
    330   gfx::Rect visible_content_rect() const {
    331     return draw_properties_.visible_content_rect;
    332   }
    333   LayerImpl* render_target() {
    334     DCHECK(!draw_properties_.render_target ||
    335            draw_properties_.render_target->render_surface());
    336     return draw_properties_.render_target;
    337   }
    338   const LayerImpl* render_target() const {
    339     DCHECK(!draw_properties_.render_target ||
    340            draw_properties_.render_target->render_surface());
    341     return draw_properties_.render_target;
    342   }
    343   RenderSurfaceImpl* render_surface() const {
    344     return draw_properties_.render_surface.get();
    345   }
    346   int num_unclipped_descendants() const {
    347     return draw_properties_.num_unclipped_descendants;
    348   }
    349 
    350   // The client should be responsible for setting bounds, content bounds and
    351   // contents scale to appropriate values. LayerImpl doesn't calculate any of
    352   // them from the other values.
    353 
    354   void SetBounds(gfx::Size bounds);
    355   gfx::Size bounds() const { return bounds_; }
    356 
    357   void SetContentBounds(gfx::Size content_bounds);
    358   gfx::Size content_bounds() const { return draw_properties_.content_bounds; }
    359 
    360   float contents_scale_x() const { return draw_properties_.contents_scale_x; }
    361   float contents_scale_y() const { return draw_properties_.contents_scale_y; }
    362   void SetContentsScale(float contents_scale_x, float contents_scale_y);
    363 
    364   // Computes a box in screen space that should entirely contain the layer's
    365   // bounds through the entirety of the layer's current animation. Returns true
    366   // and sets |out| to the inflation if there are animations that can inflate
    367   // bounds in the path to the root layer. Returns false otherwise.
    368   bool GetAnimationBounds(gfx::BoxF* out) const { return false; }
    369 
    370   virtual void CalculateContentsScale(float ideal_contents_scale,
    371                                       float device_scale_factor,
    372                                       float page_scale_factor,
    373                                       bool animating_transform_to_screen,
    374                                       float* contents_scale_x,
    375                                       float* contents_scale_y,
    376                                       gfx::Size* content_bounds);
    377 
    378   void SetScrollOffsetDelegate(
    379       LayerScrollOffsetDelegate* scroll_offset_delegate);
    380   bool IsExternalFlingActive() const;
    381 
    382   void SetScrollOffset(gfx::Vector2d scroll_offset);
    383   void SetScrollOffsetAndDelta(gfx::Vector2d scroll_offset,
    384                                gfx::Vector2dF scroll_delta);
    385   gfx::Vector2d scroll_offset() const { return scroll_offset_; }
    386 
    387   void SetMaxScrollOffset(gfx::Vector2d max_scroll_offset);
    388   gfx::Vector2d max_scroll_offset() const { return max_scroll_offset_; }
    389 
    390   void SetScrollDelta(gfx::Vector2dF scroll_delta);
    391   gfx::Vector2dF ScrollDelta() const;
    392 
    393   gfx::Vector2dF TotalScrollOffset() const;
    394 
    395   void SetSentScrollDelta(gfx::Vector2d sent_scroll_delta);
    396   gfx::Vector2d sent_scroll_delta() const { return sent_scroll_delta_; }
    397 
    398   // Returns the delta of the scroll that was outside of the bounds of the
    399   // initial scroll
    400   gfx::Vector2dF ScrollBy(gfx::Vector2dF scroll);
    401 
    402   void SetScrollable(bool scrollable) { scrollable_ = scrollable; }
    403   bool scrollable() const { return scrollable_; }
    404 
    405   void set_user_scrollable_horizontal(bool scrollable) {
    406     user_scrollable_horizontal_ = scrollable;
    407   }
    408   void set_user_scrollable_vertical(bool scrollable) {
    409     user_scrollable_vertical_ = scrollable;
    410   }
    411 
    412   void ApplySentScrollDeltasFromAbortedCommit();
    413   void ApplyScrollDeltasSinceBeginMainFrame();
    414 
    415   void SetShouldScrollOnMainThread(bool should_scroll_on_main_thread) {
    416     should_scroll_on_main_thread_ = should_scroll_on_main_thread;
    417   }
    418   bool should_scroll_on_main_thread() const {
    419     return should_scroll_on_main_thread_;
    420   }
    421 
    422   void SetHaveWheelEventHandlers(bool have_wheel_event_handlers) {
    423     have_wheel_event_handlers_ = have_wheel_event_handlers;
    424   }
    425   bool have_wheel_event_handlers() const { return have_wheel_event_handlers_; }
    426 
    427   void SetNonFastScrollableRegion(const Region& region) {
    428     non_fast_scrollable_region_ = region;
    429   }
    430   const Region& non_fast_scrollable_region() const {
    431     return non_fast_scrollable_region_;
    432   }
    433 
    434   void SetTouchEventHandlerRegion(const Region& region) {
    435     touch_event_handler_region_ = region;
    436   }
    437   const Region& touch_event_handler_region() const {
    438     return touch_event_handler_region_;
    439   }
    440 
    441   void SetDrawCheckerboardForMissingTiles(bool checkerboard) {
    442     draw_checkerboard_for_missing_tiles_ = checkerboard;
    443   }
    444   bool DrawCheckerboardForMissingTiles() const;
    445 
    446   InputHandler::ScrollStatus TryScroll(
    447       gfx::PointF screen_space_point,
    448       InputHandler::ScrollInputType type) const;
    449 
    450   void SetDoubleSided(bool double_sided);
    451   bool double_sided() const { return double_sided_; }
    452 
    453   void SetTransform(const gfx::Transform& transform);
    454   const gfx::Transform& transform() const { return transform_; }
    455   bool TransformIsAnimating() const;
    456   bool TransformIsAnimatingOnImplOnly() const;
    457 
    458   // Note this rect is in layer space (not content space).
    459   void set_update_rect(const gfx::RectF& update_rect) {
    460     update_rect_ = update_rect;
    461   }
    462   const gfx::RectF& update_rect() const { return update_rect_; }
    463 
    464   virtual base::DictionaryValue* LayerTreeAsJson() const;
    465 
    466   void SetStackingOrderChanged(bool stacking_order_changed);
    467 
    468   bool LayerPropertyChanged() const {
    469     return layer_property_changed_ || LayerIsAlwaysDamaged();
    470   }
    471 
    472   void ResetAllChangeTrackingForSubtree();
    473 
    474   virtual bool LayerIsAlwaysDamaged() const;
    475 
    476   LayerAnimationController* layer_animation_controller() {
    477     return layer_animation_controller_.get();
    478   }
    479 
    480   virtual Region VisibleContentOpaqueRegion() const;
    481 
    482   virtual void DidBecomeActive();
    483 
    484   virtual void DidBeginTracing();
    485 
    486   // Indicates that the surface previously used to render this layer
    487   // was lost and that a new one has been created. Won't be called
    488   // until the new surface has been created successfully.
    489   virtual void DidLoseOutputSurface();
    490 
    491   ScrollbarAnimationController* scrollbar_animation_controller() const {
    492     return scrollbar_animation_controller_.get();
    493   }
    494 
    495   void SetHorizontalScrollbarLayer(ScrollbarLayerImplBase* scrollbar_layer);
    496   ScrollbarLayerImplBase* horizontal_scrollbar_layer() {
    497     return horizontal_scrollbar_layer_;
    498   }
    499 
    500   void SetVerticalScrollbarLayer(ScrollbarLayerImplBase* scrollbar_layer);
    501   ScrollbarLayerImplBase* vertical_scrollbar_layer() {
    502     return vertical_scrollbar_layer_;
    503   }
    504 
    505   gfx::Rect LayerRectToContentRect(const gfx::RectF& layer_rect) const;
    506 
    507   virtual skia::RefPtr<SkPicture> GetPicture();
    508 
    509   virtual bool AreVisibleResourcesReady() const;
    510 
    511   virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl);
    512   virtual void PushPropertiesTo(LayerImpl* layer);
    513 
    514   scoped_ptr<base::Value> AsValue() const;
    515   virtual size_t GPUMemoryUsageInBytes() const;
    516 
    517   // TODO(danakj): Be true only if needed. crbug.com/259511
    518   bool needs_push_properties() const { return true; }
    519   bool descendant_needs_push_properties() const { return true; }
    520 
    521   virtual void RunMicroBenchmark(MicroBenchmarkImpl* benchmark);
    522 
    523   virtual void SetDebugInfo(
    524       scoped_refptr<base::debug::ConvertableToTraceFormat> other);
    525 
    526  protected:
    527   LayerImpl(LayerTreeImpl* layer_impl, int id);
    528 
    529   // Get the color and size of the layer's debug border.
    530   virtual void GetDebugBorderProperties(SkColor* color, float* width) const;
    531 
    532   void AppendDebugBorderQuad(QuadSink* quad_sink,
    533                              const SharedQuadState* shared_quad_state,
    534                              AppendQuadsData* append_quads_data) const;
    535   void AppendDebugBorderQuad(QuadSink* quad_sink,
    536                              const SharedQuadState* shared_quad_state,
    537                              AppendQuadsData* append_quads_data,
    538                              SkColor color,
    539                              float width) const;
    540 
    541   virtual void AsValueInto(base::DictionaryValue* dict) const;
    542 
    543   void NoteLayerPropertyChanged();
    544   void NoteLayerPropertyChangedForSubtree();
    545 
    546   // Note carefully this does not affect the current layer.
    547   void NoteLayerPropertyChangedForDescendants();
    548 
    549  private:
    550   void UpdateScrollbarPositions();
    551 
    552   virtual const char* LayerTypeAsString() const;
    553 
    554   // Properties internal to LayerImpl
    555   LayerImpl* parent_;
    556   OwnedLayerImplList children_;
    557 
    558   LayerImpl* scroll_parent_;
    559 
    560   // Storing a pointer to a set rather than a set since this will be rarely
    561   // used. If this pointer turns out to be too heavy, we could have this (and
    562   // the scroll parent above) be stored in a LayerImpl -> scroll_info
    563   // map somewhere.
    564   scoped_ptr<std::set<LayerImpl*> > scroll_children_;
    565 
    566   LayerImpl* clip_parent_;
    567   scoped_ptr<std::set<LayerImpl*> > clip_children_;
    568 
    569   // mask_layer_ can be temporarily stolen during tree sync, we need this ID to
    570   // confirm newly assigned layer is still the previous one
    571   int mask_layer_id_;
    572   scoped_ptr<LayerImpl> mask_layer_;
    573   int replica_layer_id_;  // ditto
    574   scoped_ptr<LayerImpl> replica_layer_;
    575   int layer_id_;
    576   LayerTreeImpl* layer_tree_impl_;
    577 
    578   // Properties synchronized from the associated Layer.
    579   gfx::PointF anchor_point_;
    580   float anchor_point_z_;
    581   gfx::Size bounds_;
    582   gfx::Vector2d scroll_offset_;
    583   LayerScrollOffsetDelegate* scroll_offset_delegate_;
    584   bool scrollable_ : 1;
    585   bool should_scroll_on_main_thread_ : 1;
    586   bool have_wheel_event_handlers_ : 1;
    587   bool user_scrollable_horizontal_ : 1;
    588   bool user_scrollable_vertical_ : 1;
    589   bool stacking_order_changed_ : 1;
    590   // Whether the "back" of this layer should draw.
    591   bool double_sided_ : 1;
    592 
    593   // Tracks if drawing-related properties have changed since last redraw.
    594   bool layer_property_changed_ : 1;
    595 
    596   bool masks_to_bounds_ : 1;
    597   bool contents_opaque_ : 1;
    598   bool is_root_for_isolated_group_ : 1;
    599   bool preserves_3d_ : 1;
    600   bool use_parent_backface_visibility_ : 1;
    601   bool draw_checkerboard_for_missing_tiles_ : 1;
    602   bool draws_content_ : 1;
    603   bool hide_layer_and_subtree_ : 1;
    604   bool force_render_surface_ : 1;
    605 
    606   // Set for the layer that other layers are fixed to.
    607   bool is_container_for_fixed_position_layers_ : 1;
    608   Region non_fast_scrollable_region_;
    609   Region touch_event_handler_region_;
    610   SkColor background_color_;
    611 
    612   float opacity_;
    613   SkXfermode::Mode blend_mode_;
    614   gfx::PointF position_;
    615   gfx::Transform sublayer_transform_;
    616   gfx::Transform transform_;
    617 
    618   // This property is effective when
    619   // is_container_for_fixed_position_layers_ == true,
    620   gfx::Vector2dF fixed_container_size_delta_;
    621 
    622   LayerPositionConstraint position_constraint_;
    623 
    624   gfx::Vector2dF scroll_delta_;
    625   gfx::Vector2d sent_scroll_delta_;
    626   gfx::Vector2d max_scroll_offset_;
    627   gfx::Vector2dF last_scroll_offset_;
    628 
    629   // The global depth value of the center of the layer. This value is used
    630   // to sort layers from back to front.
    631   float draw_depth_;
    632 
    633   // Debug layer name.
    634   std::string debug_name_;
    635   CompositingReasons compositing_reasons_;
    636 
    637   FilterOperations filters_;
    638   FilterOperations background_filters_;
    639 
    640  protected:
    641   DrawMode current_draw_mode_;
    642 
    643  private:
    644   // Rect indicating what was repainted/updated during update.
    645   // Note that plugin layers bypass this and leave it empty.
    646   // Uses layer (not content) space.
    647   gfx::RectF update_rect_;
    648 
    649   // Manages animations for this layer.
    650   scoped_refptr<LayerAnimationController> layer_animation_controller_;
    651 
    652   // Manages scrollbars for this layer
    653   scoped_ptr<ScrollbarAnimationController> scrollbar_animation_controller_;
    654 
    655   // Weak pointers to this layer's scrollbars, if it has them. Updated during
    656   // tree synchronization.
    657   ScrollbarLayerImplBase* horizontal_scrollbar_layer_;
    658   ScrollbarLayerImplBase* vertical_scrollbar_layer_;
    659 
    660   ScopedPtrVector<CopyOutputRequest> copy_requests_;
    661 
    662   // Group of properties that need to be computed based on the layer tree
    663   // hierarchy before layers can be drawn.
    664   DrawProperties<LayerImpl> draw_properties_;
    665 
    666   scoped_refptr<base::debug::ConvertableToTraceFormat> debug_info_;
    667 
    668   DISALLOW_COPY_AND_ASSIGN(LayerImpl);
    669 };
    670 
    671 }  // namespace cc
    672 
    673 #endif  // CC_LAYERS_LAYER_IMPL_H_
    674