layer.h revision f2477e01787aa58f445919b809d89e252beef54f 
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
11#include "base/callback.h"
12#include "base/memory/ref_counted.h"
13#include "base/observer_list.h"
14#include "cc/animation/layer_animation_controller.h"
15#include "cc/animation/layer_animation_value_observer.h"
16#include "cc/base/cc_export.h"
17#include "cc/base/region.h"
18#include "cc/base/scoped_ptr_vector.h"
19#include "cc/debug/micro_benchmark.h"
20#include "cc/layers/compositing_reasons.h"
21#include "cc/layers/draw_properties.h"
22#include "cc/layers/layer_lists.h"
23#include "cc/layers/layer_position_constraint.h"
24#include "cc/layers/paint_properties.h"
25#include "cc/layers/render_surface.h"
26#include "cc/output/filter_operations.h"
27#include "cc/trees/occlusion_tracker.h"
28#include "skia/ext/refptr.h"
29#include "third_party/skia/include/core/SkColor.h"
30#include "third_party/skia/include/core/SkImageFilter.h"
31#include "third_party/skia/include/core/SkPicture.h"
32#include "third_party/skia/include/core/SkXfermode.h"
33#include "ui/gfx/rect.h"
34#include "ui/gfx/rect_f.h"
35#include "ui/gfx/transform.h"
36
37namespace gfx {
38class BoxF;
39}
40
41namespace cc {
42
43class Animation;
44class AnimationDelegate;
45struct AnimationEvent;
46class CopyOutputRequest;
47class LayerAnimationDelegate;
48class LayerAnimationEventObserver;
49class LayerClient;
50class LayerImpl;
51class LayerTreeHost;
52class LayerTreeImpl;
53class PriorityCalculator;
54class RenderingStatsInstrumentation;
55class ResourceUpdateQueue;
56class ScrollbarLayerInterface;
57struct AnimationEvent;
58
59// Base class for composited layers. Special layer types are derived from
60// this class.
61class CC_EXPORT Layer : public base::RefCounted<Layer>,
62                        public LayerAnimationValueObserver {
63 public:
64  typedef RenderSurfaceLayerList RenderSurfaceListType;
65  typedef LayerList LayerListType;
66  typedef RenderSurface RenderSurfaceType;
67
68  enum LayerIdLabels {
69    INVALID_ID = -1,
70  };
71
72  static scoped_refptr<Layer> Create();
73
74  int id() const { return layer_id_; }
75
76  Layer* RootLayer();
77  Layer* parent() { return parent_; }
78  const Layer* parent() const { return parent_; }
79  void AddChild(scoped_refptr<Layer> child);
80  void InsertChild(scoped_refptr<Layer> child, size_t index);
81  void ReplaceChild(Layer* reference, scoped_refptr<Layer> new_layer);
82  void RemoveFromParent();
83  void RemoveAllChildren();
84  void SetChildren(const LayerList& children);
85  bool HasAncestor(const Layer* ancestor) const;
86
87  const LayerList& children() const { return children_; }
88  Layer* child_at(size_t index) { return children_[index].get(); }
89
90  // This requests the layer and its subtree be rendered and given to the
91  // callback. If the copy is unable to be produced (the layer is destroyed
92  // first), then the callback is called with a NULL/empty result.
93  void RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> request);
94  bool HasCopyRequest() const {
95    return !copy_requests_.empty();
96  }
97
98  void SetAnchorPoint(gfx::PointF anchor_point);
99  gfx::PointF anchor_point() const { return anchor_point_; }
100
101  void SetAnchorPointZ(float anchor_point_z);
102  float anchor_point_z() const { return anchor_point_z_; }
103
104  virtual void SetBackgroundColor(SkColor background_color);
105  SkColor background_color() const { return background_color_; }
106  // If contents_opaque(), return an opaque color else return a
107  // non-opaque color.  Tries to return background_color(), if possible.
108  SkColor SafeOpaqueBackgroundColor() const;
109
110  // A layer's bounds are in logical, non-page-scaled pixels (however, the
111  // root layer's bounds are in physical pixels).
112  void SetBounds(gfx::Size bounds);
113  gfx::Size bounds() const { return bounds_; }
114
115  void SetMasksToBounds(bool masks_to_bounds);
116  bool masks_to_bounds() const { return masks_to_bounds_; }
117
118  void SetMaskLayer(Layer* mask_layer);
119  Layer* mask_layer() { return mask_layer_.get(); }
120  const Layer* mask_layer() const { return mask_layer_.get(); }
121
122  virtual void SetNeedsDisplayRect(const gfx::RectF& dirty_rect);
123  void SetNeedsDisplay() { SetNeedsDisplayRect(gfx::RectF(bounds())); }
124
125  void SetOpacity(float opacity);
126  float opacity() const { return opacity_; }
127  bool OpacityIsAnimating() const;
128  virtual bool OpacityCanAnimateOnImplThread() const;
129
130  void SetBlendMode(SkXfermode::Mode blend_mode);
131  SkXfermode::Mode blend_mode() const { return blend_mode_; }
132
133  bool uses_default_blend_mode() const {
134    return blend_mode_ == SkXfermode::kSrcOver_Mode;
135  }
136
137  // A layer is root for an isolated group when it and all its descendants are
138  // drawn over a black and fully transparent background, creating an isolated
139  // group. It should be used along with SetBlendMode(), in order to restrict
140  // layers within the group to blend with layers outside this group.
141  void SetIsRootForIsolatedGroup(bool root);
142  bool is_root_for_isolated_group() const {
143    return is_root_for_isolated_group_;
144  }
145
146  void SetFilters(const FilterOperations& filters);
147  const FilterOperations& filters() const { return filters_; }
148  bool FilterIsAnimating() const;
149
150  // Background filters are filters applied to what is behind this layer, when
151  // they are viewed through non-opaque regions in this layer. They are used
152  // through the WebLayer interface, and are not exposed to HTML.
153  void SetBackgroundFilters(const FilterOperations& filters);
154  const FilterOperations& background_filters() const {
155    return background_filters_;
156  }
157
158  virtual void SetContentsOpaque(bool opaque);
159  bool contents_opaque() const { return contents_opaque_; }
160
161  void SetPosition(gfx::PointF position);
162  gfx::PointF position() const { return position_; }
163
164  void SetIsContainerForFixedPositionLayers(bool container);
165  bool IsContainerForFixedPositionLayers() const;
166
167  void SetPositionConstraint(const LayerPositionConstraint& constraint);
168  const LayerPositionConstraint& position_constraint() const {
169    return position_constraint_;
170  }
171
172  void SetSublayerTransform(const gfx::Transform& sublayer_transform);
173  const gfx::Transform& sublayer_transform() const {
174    return sublayer_transform_;
175  }
176
177  void SetTransform(const gfx::Transform& transform);
178  const gfx::Transform& transform() const { return transform_; }
179  bool TransformIsAnimating() const;
180
181  void SetScrollParent(Layer* parent);
182
183  Layer* scroll_parent() { return scroll_parent_; }
184  const Layer* scroll_parent() const { return scroll_parent_; }
185
186  void AddScrollChild(Layer* child);
187  void RemoveScrollChild(Layer* child);
188
189  std::set<Layer*>* scroll_children() { return scroll_children_.get(); }
190  const std::set<Layer*>* scroll_children() const {
191    return scroll_children_.get();
192  }
193
194  void SetClipParent(Layer* ancestor);
195
196  Layer* clip_parent() { return clip_parent_; }
197  const Layer* clip_parent() const {
198    return clip_parent_;
199  }
200
201  void AddClipChild(Layer* child);
202  void RemoveClipChild(Layer* child);
203
204  std::set<Layer*>* clip_children() { return clip_children_.get(); }
205  const std::set<Layer*>* clip_children() const {
206    return clip_children_.get();
207  }
208
209  DrawProperties<Layer>& draw_properties() { return draw_properties_; }
210  const DrawProperties<Layer>& draw_properties() const {
211    return draw_properties_;
212  }
213
214  // The following are shortcut accessors to get various information from
215  // draw_properties_
216  const gfx::Transform& draw_transform() const {
217    return draw_properties_.target_space_transform;
218  }
219  const gfx::Transform& screen_space_transform() const {
220    return draw_properties_.screen_space_transform;
221  }
222  float draw_opacity() const { return draw_properties_.opacity; }
223  bool draw_opacity_is_animating() const {
224    return draw_properties_.opacity_is_animating;
225  }
226  bool draw_transform_is_animating() const {
227    return draw_properties_.target_space_transform_is_animating;
228  }
229  bool screen_space_transform_is_animating() const {
230    return draw_properties_.screen_space_transform_is_animating;
231  }
232  bool screen_space_opacity_is_animating() const {
233    return draw_properties_.screen_space_opacity_is_animating;
234  }
235  bool can_use_lcd_text() const { return draw_properties_.can_use_lcd_text; }
236  bool is_clipped() const { return draw_properties_.is_clipped; }
237  gfx::Rect clip_rect() const { return draw_properties_.clip_rect; }
238  gfx::Rect drawable_content_rect() const {
239    return draw_properties_.drawable_content_rect;
240  }
241  gfx::Rect visible_content_rect() const {
242    return draw_properties_.visible_content_rect;
243  }
244  Layer* render_target() {
245    DCHECK(!draw_properties_.render_target ||
246           draw_properties_.render_target->render_surface());
247    return draw_properties_.render_target;
248  }
249  const Layer* render_target() const {
250    DCHECK(!draw_properties_.render_target ||
251           draw_properties_.render_target->render_surface());
252    return draw_properties_.render_target;
253  }
254  RenderSurface* render_surface() const {
255    return draw_properties_.render_surface.get();
256  }
257  int num_unclipped_descendants() const {
258    return draw_properties_.num_unclipped_descendants;
259  }
260
261  void SetScrollOffset(gfx::Vector2d scroll_offset);
262  gfx::Vector2d scroll_offset() const { return scroll_offset_; }
263  void SetScrollOffsetFromImplSide(gfx::Vector2d scroll_offset);
264
265  void SetMaxScrollOffset(gfx::Vector2d max_scroll_offset);
266  gfx::Vector2d max_scroll_offset() const { return max_scroll_offset_; }
267
268  void SetScrollable(bool scrollable);
269  bool scrollable() const { return scrollable_; }
270
271  void SetUserScrollable(bool horizontal, bool vertical);
272  bool user_scrollable_horizontal() const {
273    return user_scrollable_horizontal_;
274  }
275  bool user_scrollable_vertical() const { return user_scrollable_vertical_; }
276
277  void SetShouldScrollOnMainThread(bool should_scroll_on_main_thread);
278  bool should_scroll_on_main_thread() const {
279    return should_scroll_on_main_thread_;
280  }
281
282  void SetHaveWheelEventHandlers(bool have_wheel_event_handlers);
283  bool have_wheel_event_handlers() const { return have_wheel_event_handlers_; }
284
285  void SetNonFastScrollableRegion(const Region& non_fast_scrollable_region);
286  const Region& non_fast_scrollable_region() const {
287    return non_fast_scrollable_region_;
288  }
289
290  void SetTouchEventHandlerRegion(const Region& touch_event_handler_region);
291  const Region& touch_event_handler_region() const {
292    return touch_event_handler_region_;
293  }
294
295  void set_did_scroll_callback(const base::Closure& callback) {
296    did_scroll_callback_ = callback;
297  }
298
299  void SetDrawCheckerboardForMissingTiles(bool checkerboard);
300  bool DrawCheckerboardForMissingTiles() const {
301    return draw_checkerboard_for_missing_tiles_;
302  }
303
304  void SetForceRenderSurface(bool force_render_surface);
305  bool force_render_surface() const { return force_render_surface_; }
306
307  gfx::Vector2d ScrollDelta() const { return gfx::Vector2d(); }
308  gfx::Vector2dF TotalScrollOffset() const {
309    // Floating point to match the LayerImpl version.
310    return scroll_offset() + ScrollDelta();
311  }
312
313  void SetDoubleSided(bool double_sided);
314  bool double_sided() const { return double_sided_; }
315
316  void SetPreserves3d(bool preserves_3d) { preserves_3d_ = preserves_3d; }
317  bool preserves_3d() const { return preserves_3d_; }
318
319  void set_use_parent_backface_visibility(bool use) {
320    use_parent_backface_visibility_ = use;
321  }
322  bool use_parent_backface_visibility() const {
323    return use_parent_backface_visibility_;
324  }
325
326  virtual void SetLayerTreeHost(LayerTreeHost* host);
327
328  bool HasDelegatedContent() const { return false; }
329  bool HasContributingDelegatedRenderPasses() const { return false; }
330
331  void SetIsDrawable(bool is_drawable);
332
333  void SetHideLayerAndSubtree(bool hide);
334  bool hide_layer_and_subtree() const { return hide_layer_and_subtree_; }
335
336  void SetReplicaLayer(Layer* layer);
337  Layer* replica_layer() { return replica_layer_.get(); }
338  const Layer* replica_layer() const { return replica_layer_.get(); }
339
340  bool has_mask() const { return !!mask_layer_.get(); }
341  bool has_replica() const { return !!replica_layer_.get(); }
342  bool replica_has_mask() const {
343    return replica_layer_.get() &&
344           (mask_layer_.get() || replica_layer_->mask_layer_.get());
345  }
346
347  // These methods typically need to be overwritten by derived classes.
348  virtual bool DrawsContent() const;
349  virtual void SavePaintProperties();
350  // Returns true iff any resources were updated that need to be committed.
351  virtual bool Update(ResourceUpdateQueue* queue,
352                      const OcclusionTracker* occlusion);
353  virtual bool NeedMoreUpdates();
354  virtual void SetIsMask(bool is_mask) {}
355  virtual void ReduceMemoryUsage() {}
356  virtual void OnOutputSurfaceCreated() {}
357
358  virtual std::string DebugName();
359
360  void SetLayerClient(LayerClient* client) { client_ = client; }
361
362  void SetCompositingReasons(CompositingReasons reasons);
363
364  virtual void PushPropertiesTo(LayerImpl* layer);
365
366  void CreateRenderSurface();
367  void ClearRenderSurface();
368
369  // The contents scale converts from logical, non-page-scaled pixels to target
370  // pixels. The contents scale is 1 for the root layer as it is already in
371  // physical pixels. By default contents scale is forced to be 1 except for
372  // subclasses of ContentsScalingLayer.
373  float contents_scale_x() const { return draw_properties_.contents_scale_x; }
374  float contents_scale_y() const { return draw_properties_.contents_scale_y; }
375  gfx::Size content_bounds() const { return draw_properties_.content_bounds; }
376
377  virtual void CalculateContentsScale(float ideal_contents_scale,
378                                      float device_scale_factor,
379                                      float page_scale_factor,
380                                      bool animating_transform_to_screen,
381                                      float* contents_scale_x,
382                                      float* contents_scale_y,
383                                      gfx::Size* content_bounds);
384
385  LayerTreeHost* layer_tree_host() { return layer_tree_host_; }
386  const LayerTreeHost* layer_tree_host() const { return layer_tree_host_; }
387
388  // Set the priority of all desired textures in this layer.
389  virtual void SetTexturePriorities(const PriorityCalculator& priority_calc) {}
390
391  bool AddAnimation(scoped_ptr<Animation> animation);
392  void PauseAnimation(int animation_id, double time_offset);
393  void RemoveAnimation(int animation_id);
394
395  bool AnimatedBoundsForBox(const gfx::BoxF& box, gfx::BoxF* bounds) {
396    return layer_animation_controller_->AnimatedBoundsForBox(box, bounds);
397  }
398
399  LayerAnimationController* layer_animation_controller() {
400    return layer_animation_controller_.get();
401  }
402  void SetLayerAnimationControllerForTest(
403      scoped_refptr<LayerAnimationController> controller);
404
405  void set_layer_animation_delegate(AnimationDelegate* delegate) {
406    layer_animation_controller_->set_layer_animation_delegate(delegate);
407  }
408
409  bool HasActiveAnimation() const;
410
411  void AddLayerAnimationEventObserver(
412      LayerAnimationEventObserver* animation_observer);
413  void RemoveLayerAnimationEventObserver(
414      LayerAnimationEventObserver* animation_observer);
415
416  virtual Region VisibleContentOpaqueRegion() const;
417
418  virtual ScrollbarLayerInterface* ToScrollbarLayer();
419
420  gfx::Rect LayerRectToContentRect(const gfx::RectF& layer_rect) const;
421
422  virtual skia::RefPtr<SkPicture> GetPicture() const;
423
424  // Constructs a LayerImpl of the correct runtime type for this Layer type.
425  virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl);
426
427  bool NeedsDisplayForTesting() const { return !update_rect_.IsEmpty(); }
428  void ResetNeedsDisplayForTesting() { update_rect_ = gfx::RectF(); }
429
430  RenderingStatsInstrumentation* rendering_stats_instrumentation() const;
431
432  const PaintProperties& paint_properties() const {
433    return paint_properties_;
434  }
435
436  // The scale at which contents should be rastered, to match the scale at
437  // which they will drawn to the screen. This scale is a component of the
438  // contents scale but does not include page/device scale factors.
439  // TODO(danakj): This goes away when TiledLayer goes away.
440  void set_raster_scale(float scale) { raster_scale_ = scale; }
441  float raster_scale() const { return raster_scale_; }
442  bool raster_scale_is_unknown() const { return raster_scale_ == 0.f; }
443
444  virtual bool SupportsLCDText() const;
445
446  bool needs_push_properties() const { return needs_push_properties_; }
447  bool descendant_needs_push_properties() const {
448    return num_dependents_need_push_properties_ > 0;
449  }
450
451  virtual void RunMicroBenchmark(MicroBenchmark* benchmark);
452
453 protected:
454  friend class LayerImpl;
455  friend class TreeSynchronizer;
456  virtual ~Layer();
457
458  Layer();
459
460  // These SetNeeds functions are in order of severity of update:
461  //
462  // Called when this layer has been modified in some way, but isn't sure
463  // that it needs a commit yet.  It needs CalcDrawProperties and UpdateLayers
464  // before it knows whether or not a commit is required.
465  void SetNeedsUpdate();
466  // Called when a property has been modified in a way that the layer
467  // knows immediately that a commit is required.  This implies SetNeedsUpdate
468  // as well as SetNeedsPushProperties to push that property.
469  void SetNeedsCommit();
470  // Called when there's been a change in layer structure.  Implies both
471  // SetNeedsUpdate and SetNeedsCommit, but not SetNeedsPushProperties.
472  void SetNeedsFullTreeSync();
473
474  // Called when the next commit should wait until the pending tree is activated
475  // before finishing the commit and unblocking the main thread. Used to ensure
476  // unused resources on the impl thread are returned before commit completes.
477  void SetNextCommitWaitsForActivation();
478
479  // Called when the blend mode or filters have been changed.
480  void SetNeedsFilterContextIfNeeded();
481
482  void SetNeedsPushProperties();
483  void AddDependentNeedsPushProperties();
484  void RemoveDependentNeedsPushProperties();
485  bool parent_should_know_need_push_properties() const {
486    return needs_push_properties() || descendant_needs_push_properties();
487  }
488
489  bool IsPropertyChangeAllowed() const;
490
491  // If this layer has a scroll parent, it removes |this| from its list of
492  // scroll children.
493  void RemoveFromScrollTree();
494
495  // If this layer has a clip parent, it removes |this| from its list of clip
496  // children.
497  void RemoveFromClipTree();
498
499  void reset_raster_scale_to_unknown() { raster_scale_ = 0.f; }
500
501  // This flag is set when the layer needs to push properties to the impl
502  // side.
503  bool needs_push_properties_;
504
505  // The number of direct children or dependent layers that need to be recursed
506  // to in order for them or a descendent of them to push properties to the impl
507  // side.
508  int num_dependents_need_push_properties_;
509
510  // Tracks whether this layer may have changed stacking order with its
511  // siblings.
512  bool stacking_order_changed_;
513
514  // The update rect is the region of the compositor resource that was
515  // actually updated by the compositor. For layers that may do updating
516  // outside the compositor's control (i.e. plugin layers), this information
517  // is not available and the update rect will remain empty.
518  // Note this rect is in layer space (not content space).
519  gfx::RectF update_rect_;
520
521  scoped_refptr<Layer> mask_layer_;
522
523  int layer_id_;
524
525  // When true, the layer is about to perform an update. Any commit requests
526  // will be handled implicitly after the update completes.
527  bool ignore_set_needs_commit_;
528
529 private:
530  friend class base::RefCounted<Layer>;
531
532  void SetParent(Layer* layer);
533  bool DescendantIsFixedToContainerLayer() const;
534
535  // Returns the index of the child or -1 if not found.
536  int IndexOfChild(const Layer* reference);
537
538  // This should only be called from RemoveFromParent().
539  void RemoveChildOrDependent(Layer* child);
540
541  // LayerAnimationValueObserver implementation.
542  virtual void OnFilterAnimated(const FilterOperations& filters) OVERRIDE;
543  virtual void OnOpacityAnimated(float opacity) OVERRIDE;
544  virtual void OnTransformAnimated(const gfx::Transform& transform) OVERRIDE;
545  virtual void OnAnimationWaitingForDeletion() OVERRIDE;
546  virtual bool IsActive() const OVERRIDE;
547
548  LayerList children_;
549  Layer* parent_;
550
551  // Layer instances have a weak pointer to their LayerTreeHost.
552  // This pointer value is nil when a Layer is not in a tree and is
553  // updated via SetLayerTreeHost() if a layer moves between trees.
554  LayerTreeHost* layer_tree_host_;
555
556  scoped_refptr<LayerAnimationController> layer_animation_controller_;
557
558  // Layer properties.
559  gfx::Size bounds_;
560
561  gfx::Vector2d scroll_offset_;
562  gfx::Vector2d max_scroll_offset_;
563  bool scrollable_;
564  bool should_scroll_on_main_thread_;
565  bool have_wheel_event_handlers_;
566  bool user_scrollable_horizontal_;
567  bool user_scrollable_vertical_;
568  Region non_fast_scrollable_region_;
569  Region touch_event_handler_region_;
570  gfx::PointF position_;
571  gfx::PointF anchor_point_;
572  SkColor background_color_;
573  CompositingReasons compositing_reasons_;
574  float opacity_;
575  SkXfermode::Mode blend_mode_;
576  bool is_root_for_isolated_group_;
577  FilterOperations filters_;
578  FilterOperations background_filters_;
579  float anchor_point_z_;
580  bool is_container_for_fixed_position_layers_;
581  LayerPositionConstraint position_constraint_;
582  bool is_drawable_;
583  bool hide_layer_and_subtree_;
584  bool masks_to_bounds_;
585  bool contents_opaque_;
586  bool double_sided_;
587  bool preserves_3d_;
588  bool use_parent_backface_visibility_;
589  bool draw_checkerboard_for_missing_tiles_;
590  bool force_render_surface_;
591  Layer* scroll_parent_;
592  scoped_ptr<std::set<Layer*> > scroll_children_;
593
594  Layer* clip_parent_;
595  scoped_ptr<std::set<Layer*> > clip_children_;
596
597  gfx::Transform transform_;
598  gfx::Transform sublayer_transform_;
599
600  // Replica layer used for reflections.
601  scoped_refptr<Layer> replica_layer_;
602
603  // Transient properties.
604  float raster_scale_;
605
606  LayerClient* client_;
607
608  ScopedPtrVector<CopyOutputRequest> copy_requests_;
609
610  base::Closure did_scroll_callback_;
611
612  DrawProperties<Layer> draw_properties_;
613
614  PaintProperties paint_properties_;
615
616  DISALLOW_COPY_AND_ASSIGN(Layer);
617};
618
619}  // namespace cc
620
621#endif  // CC_LAYERS_LAYER_H_
622