layer.h revision 68043e1e95eeb07d5cae7aca370b26518b0867d6 
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/layers/compositing_reasons.h"
20#include "cc/layers/draw_properties.h"
21#include "cc/layers/layer_lists.h"
22#include "cc/layers/layer_position_constraint.h"
23#include "cc/layers/paint_properties.h"
24#include "cc/layers/render_surface.h"
25#include "cc/output/filter_operations.h"
26#include "cc/trees/occlusion_tracker.h"
27#include "skia/ext/refptr.h"
28#include "third_party/skia/include/core/SkColor.h"
29#include "third_party/skia/include/core/SkImageFilter.h"
30#include "third_party/skia/include/core/SkPicture.h"
31#include "ui/gfx/rect.h"
32#include "ui/gfx/rect_f.h"
33#include "ui/gfx/transform.h"
34
35namespace gfx {
36class BoxF;
37}
38
39namespace cc {
40
41class Animation;
42class AnimationDelegate;
43struct AnimationEvent;
44class CopyOutputRequest;
45class LayerAnimationDelegate;
46class LayerAnimationEventObserver;
47class LayerClient;
48class LayerImpl;
49class LayerTreeHost;
50class LayerTreeImpl;
51class PriorityCalculator;
52class RenderingStatsInstrumentation;
53class ResourceUpdateQueue;
54class ScrollbarLayerInterface;
55struct AnimationEvent;
56
57// Base class for composited layers. Special layer types are derived from
58// this class.
59class CC_EXPORT Layer : public base::RefCounted<Layer>,
60                        public LayerAnimationValueObserver {
61 public:
62  enum LayerIdLabels {
63    INVALID_ID = -1,
64  };
65
66  static scoped_refptr<Layer> Create();
67
68  int id() const { return layer_id_; }
69
70  Layer* RootLayer();
71  Layer* parent() { return parent_; }
72  const Layer* parent() const { return parent_; }
73  void AddChild(scoped_refptr<Layer> child);
74  void InsertChild(scoped_refptr<Layer> child, size_t index);
75  void ReplaceChild(Layer* reference, scoped_refptr<Layer> new_layer);
76  void RemoveFromParent();
77  void RemoveAllChildren();
78  void SetChildren(const LayerList& children);
79  bool HasAncestor(const Layer* ancestor) const;
80
81  const LayerList& children() const { return children_; }
82  Layer* child_at(size_t index) { return children_[index].get(); }
83
84  // This requests the layer and its subtree be rendered and given to the
85  // callback. If the copy is unable to be produced (the layer is destroyed
86  // first), then the callback is called with a NULL/empty result.
87  void RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> request);
88  bool HasCopyRequest() const {
89    return !copy_requests_.empty();
90  }
91
92  void SetAnchorPoint(gfx::PointF anchor_point);
93  gfx::PointF anchor_point() const { return anchor_point_; }
94
95  void SetAnchorPointZ(float anchor_point_z);
96  float anchor_point_z() const { return anchor_point_z_; }
97
98  virtual void SetBackgroundColor(SkColor background_color);
99  SkColor background_color() const { return background_color_; }
100  // If contents_opaque(), return an opaque color else return a
101  // non-opaque color.  Tries to return background_color(), if possible.
102  SkColor SafeOpaqueBackgroundColor() const;
103
104  // A layer's bounds are in logical, non-page-scaled pixels (however, the
105  // root layer's bounds are in physical pixels).
106  void SetBounds(gfx::Size bounds);
107  gfx::Size bounds() const { return bounds_; }
108
109  void SetMasksToBounds(bool masks_to_bounds);
110  bool masks_to_bounds() const { return masks_to_bounds_; }
111
112  void SetMaskLayer(Layer* mask_layer);
113  Layer* mask_layer() { return mask_layer_.get(); }
114  const Layer* mask_layer() const { return mask_layer_.get(); }
115
116  virtual void SetNeedsDisplayRect(const gfx::RectF& dirty_rect);
117  void SetNeedsDisplay() { SetNeedsDisplayRect(gfx::RectF(bounds())); }
118
119  void SetOpacity(float opacity);
120  float opacity() const { return opacity_; }
121  bool OpacityIsAnimating() const;
122  virtual bool OpacityCanAnimateOnImplThread() const;
123
124  void SetFilters(const FilterOperations& filters);
125  const FilterOperations& filters() const { return filters_; }
126
127  // Background filters are filters applied to what is behind this layer, when
128  // they are viewed through non-opaque regions in this layer. They are used
129  // through the WebLayer interface, and are not exposed to HTML.
130  void SetBackgroundFilters(const FilterOperations& filters);
131  const FilterOperations& background_filters() const {
132    return background_filters_;
133  }
134
135  virtual void SetContentsOpaque(bool opaque);
136  bool contents_opaque() const { return contents_opaque_; }
137
138  void SetPosition(gfx::PointF position);
139  gfx::PointF position() const { return position_; }
140
141  void SetIsContainerForFixedPositionLayers(bool container);
142  bool IsContainerForFixedPositionLayers() const;
143
144  void SetPositionConstraint(const LayerPositionConstraint& constraint);
145  const LayerPositionConstraint& position_constraint() const {
146    return position_constraint_;
147  }
148
149  void SetSublayerTransform(const gfx::Transform& sublayer_transform);
150  const gfx::Transform& sublayer_transform() const {
151    return sublayer_transform_;
152  }
153
154  void SetTransform(const gfx::Transform& transform);
155  const gfx::Transform& transform() const { return transform_; }
156  bool TransformIsAnimating() const;
157
158  void SetScrollParent(Layer* parent);
159
160  Layer* scroll_parent() { return scroll_parent_; }
161  const Layer* scroll_parent() const { return scroll_parent_; }
162
163  void AddScrollChild(Layer* child);
164  void RemoveScrollChild(Layer* child);
165
166  std::set<Layer*>* scroll_children() { return scroll_children_.get(); }
167  const std::set<Layer*>* scroll_children() const {
168    return scroll_children_.get();
169  }
170
171  void SetClipParent(Layer* ancestor);
172
173  Layer* clip_parent() { return clip_parent_; }
174  const Layer* clip_parent() const {
175    return clip_parent_;
176  }
177
178  void AddClipChild(Layer* child);
179  void RemoveClipChild(Layer* child);
180
181  std::set<Layer*>* clip_children() { return clip_children_.get(); }
182  const std::set<Layer*>* clip_children() const {
183    return clip_children_.get();
184  }
185
186  DrawProperties<Layer, RenderSurface>& draw_properties() {
187    return draw_properties_;
188  }
189  const DrawProperties<Layer, RenderSurface>& draw_properties() const {
190    return draw_properties_;
191  }
192
193  // The following are shortcut accessors to get various information from
194  // draw_properties_
195  const gfx::Transform& draw_transform() const {
196    return draw_properties_.target_space_transform;
197  }
198  const gfx::Transform& screen_space_transform() const {
199    return draw_properties_.screen_space_transform;
200  }
201  float draw_opacity() const { return draw_properties_.opacity; }
202  bool draw_opacity_is_animating() const {
203    return draw_properties_.opacity_is_animating;
204  }
205  bool draw_transform_is_animating() const {
206    return draw_properties_.target_space_transform_is_animating;
207  }
208  bool screen_space_transform_is_animating() const {
209    return draw_properties_.screen_space_transform_is_animating;
210  }
211  bool screen_space_opacity_is_animating() const {
212    return draw_properties_.screen_space_opacity_is_animating;
213  }
214  bool can_use_lcd_text() const { return draw_properties_.can_use_lcd_text; }
215  bool is_clipped() const { return draw_properties_.is_clipped; }
216  gfx::Rect clip_rect() const { return draw_properties_.clip_rect; }
217  gfx::Rect drawable_content_rect() const {
218    return draw_properties_.drawable_content_rect;
219  }
220  gfx::Rect visible_content_rect() const {
221    return draw_properties_.visible_content_rect;
222  }
223  Layer* render_target() {
224    DCHECK(!draw_properties_.render_target ||
225           draw_properties_.render_target->render_surface());
226    return draw_properties_.render_target;
227  }
228  const Layer* render_target() const {
229    DCHECK(!draw_properties_.render_target ||
230           draw_properties_.render_target->render_surface());
231    return draw_properties_.render_target;
232  }
233  RenderSurface* render_surface() const {
234    return draw_properties_.render_surface.get();
235  }
236  int num_unclipped_descendants() const {
237    return draw_properties_.num_unclipped_descendants;
238  }
239
240  void SetScrollOffset(gfx::Vector2d scroll_offset);
241  gfx::Vector2d scroll_offset() const { return scroll_offset_; }
242  void SetScrollOffsetFromImplSide(gfx::Vector2d scroll_offset);
243
244  void SetMaxScrollOffset(gfx::Vector2d max_scroll_offset);
245  gfx::Vector2d max_scroll_offset() const { return max_scroll_offset_; }
246
247  void SetScrollable(bool scrollable);
248  bool scrollable() const { return scrollable_; }
249
250  void SetShouldScrollOnMainThread(bool should_scroll_on_main_thread);
251  bool should_scroll_on_main_thread() const {
252    return should_scroll_on_main_thread_;
253  }
254
255  void SetHaveWheelEventHandlers(bool have_wheel_event_handlers);
256  bool have_wheel_event_handlers() const { return have_wheel_event_handlers_; }
257
258  void SetNonFastScrollableRegion(const Region& non_fast_scrollable_region);
259  const Region& non_fast_scrollable_region() const {
260    return non_fast_scrollable_region_;
261  }
262
263  void SetTouchEventHandlerRegion(const Region& touch_event_handler_region);
264  const Region& touch_event_handler_region() const {
265    return touch_event_handler_region_;
266  }
267
268  void set_did_scroll_callback(const base::Closure& callback) {
269    did_scroll_callback_ = callback;
270  }
271
272  void SetDrawCheckerboardForMissingTiles(bool checkerboard);
273  bool DrawCheckerboardForMissingTiles() const {
274    return draw_checkerboard_for_missing_tiles_;
275  }
276
277  void SetForceRenderSurface(bool force_render_surface);
278  bool force_render_surface() const { return force_render_surface_; }
279
280  gfx::Vector2d ScrollDelta() const { return gfx::Vector2d(); }
281  gfx::Vector2dF TotalScrollOffset() const {
282    // Floating point to match the LayerImpl version.
283    return scroll_offset() + ScrollDelta();
284  }
285
286  void SetDoubleSided(bool double_sided);
287  bool double_sided() const { return double_sided_; }
288
289  void SetPreserves3d(bool preserves_3d) { preserves_3d_ = preserves_3d; }
290  bool preserves_3d() const { return preserves_3d_; }
291
292  void set_use_parent_backface_visibility(bool use) {
293    use_parent_backface_visibility_ = use;
294  }
295  bool use_parent_backface_visibility() const {
296    return use_parent_backface_visibility_;
297  }
298
299  virtual void SetLayerTreeHost(LayerTreeHost* host);
300
301  bool HasDelegatedContent() const { return false; }
302  bool HasContributingDelegatedRenderPasses() const { return false; }
303
304  void SetIsDrawable(bool is_drawable);
305
306  void SetHideLayerAndSubtree(bool hide);
307  bool hide_layer_and_subtree() const { return hide_layer_and_subtree_; }
308
309  void SetReplicaLayer(Layer* layer);
310  Layer* replica_layer() { return replica_layer_.get(); }
311  const Layer* replica_layer() const { return replica_layer_.get(); }
312
313  bool has_mask() const { return !!mask_layer_.get(); }
314  bool has_replica() const { return !!replica_layer_.get(); }
315  bool replica_has_mask() const {
316    return replica_layer_.get() &&
317           (mask_layer_.get() || replica_layer_->mask_layer_.get());
318  }
319
320  // These methods typically need to be overwritten by derived classes.
321  virtual bool DrawsContent() const;
322  virtual void SavePaintProperties();
323  // Returns true iff any resources were updated that need to be committed.
324  virtual bool Update(ResourceUpdateQueue* queue,
325                      const OcclusionTracker* occlusion);
326  virtual bool NeedMoreUpdates();
327  virtual void SetIsMask(bool is_mask) {}
328  virtual void ReduceMemoryUsage() {}
329
330  virtual std::string DebugName();
331
332  void SetLayerClient(LayerClient* client) { client_ = client; }
333
334  void SetCompositingReasons(CompositingReasons reasons);
335
336  virtual void PushPropertiesTo(LayerImpl* layer);
337
338  void CreateRenderSurface();
339  void ClearRenderSurface();
340
341  // The contents scale converts from logical, non-page-scaled pixels to target
342  // pixels. The contents scale is 1 for the root layer as it is already in
343  // physical pixels. By default contents scale is forced to be 1 except for
344  // subclasses of ContentsScalingLayer.
345  float contents_scale_x() const { return draw_properties_.contents_scale_x; }
346  float contents_scale_y() const { return draw_properties_.contents_scale_y; }
347  gfx::Size content_bounds() const { return draw_properties_.content_bounds; }
348
349  virtual void CalculateContentsScale(float ideal_contents_scale,
350                                      float device_scale_factor,
351                                      float page_scale_factor,
352                                      bool animating_transform_to_screen,
353                                      float* contents_scale_x,
354                                      float* contents_scale_y,
355                                      gfx::Size* content_bounds);
356
357  LayerTreeHost* layer_tree_host() { return layer_tree_host_; }
358  const LayerTreeHost* layer_tree_host() const { return layer_tree_host_; }
359
360  // Set the priority of all desired textures in this layer.
361  virtual void SetTexturePriorities(const PriorityCalculator& priority_calc) {}
362
363  bool AddAnimation(scoped_ptr<Animation> animation);
364  void PauseAnimation(int animation_id, double time_offset);
365  void RemoveAnimation(int animation_id);
366
367  void SuspendAnimations(double monotonic_time);
368  void ResumeAnimations(double monotonic_time);
369
370  bool AnimatedBoundsForBox(const gfx::BoxF& box, gfx::BoxF* bounds) {
371    return layer_animation_controller_->AnimatedBoundsForBox(box, bounds);
372  }
373
374  LayerAnimationController* layer_animation_controller() {
375    return layer_animation_controller_.get();
376  }
377  void SetLayerAnimationControllerForTest(
378      scoped_refptr<LayerAnimationController> controller);
379
380  void set_layer_animation_delegate(AnimationDelegate* delegate) {
381    layer_animation_controller_->set_layer_animation_delegate(delegate);
382  }
383
384  bool HasActiveAnimation() const;
385
386  void AddLayerAnimationEventObserver(
387      LayerAnimationEventObserver* animation_observer);
388  void RemoveLayerAnimationEventObserver(
389      LayerAnimationEventObserver* animation_observer);
390
391  virtual Region VisibleContentOpaqueRegion() const;
392
393  virtual ScrollbarLayerInterface* ToScrollbarLayer();
394
395  gfx::Rect LayerRectToContentRect(const gfx::RectF& layer_rect) const;
396
397  virtual skia::RefPtr<SkPicture> GetPicture() const;
398
399  virtual bool CanClipSelf() const;
400
401  // Constructs a LayerImpl of the correct runtime type for this Layer type.
402  virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl);
403
404  bool NeedsDisplayForTesting() const { return !update_rect_.IsEmpty(); }
405  void ResetNeedsDisplayForTesting() { update_rect_ = gfx::RectF(); }
406
407  RenderingStatsInstrumentation* rendering_stats_instrumentation() const;
408
409  const PaintProperties& paint_properties() const {
410    return paint_properties_;
411  }
412
413  // The scale at which contents should be rastered, to match the scale at
414  // which they will drawn to the screen. This scale is a component of the
415  // contents scale but does not include page/device scale factors.
416  // TODO(danakj): This goes away when TiledLayer goes away.
417  void set_raster_scale(float scale) { raster_scale_ = scale; }
418  float raster_scale() const { return raster_scale_; }
419  bool raster_scale_is_unknown() const { return raster_scale_ == 0.f; }
420
421  virtual bool SupportsLCDText() const;
422
423  bool needs_push_properties() const { return needs_push_properties_; }
424  bool descendant_needs_push_properties() const {
425    return num_dependents_need_push_properties_ > 0;
426  }
427
428 protected:
429  friend class LayerImpl;
430  friend class TreeSynchronizer;
431  virtual ~Layer();
432
433  Layer();
434
435  // These SetNeeds functions are in order of severity of update:
436  //
437  // Called when this layer has been modified in some way, but isn't sure
438  // that it needs a commit yet.  It needs CalcDrawProperties and UpdateLayers
439  // before it knows whether or not a commit is required.
440  void SetNeedsUpdate();
441  // Called when a property has been modified in a way that the layer
442  // knows immediately that a commit is required.  This implies SetNeedsUpdate
443  // as well as SetNeedsPushProperties to push that property.
444  void SetNeedsCommit();
445  // Called when there's been a change in layer structure.  Implies both
446  // SetNeedsUpdate and SetNeedsCommit, but not SetNeedsPushProperties.
447  void SetNeedsFullTreeSync();
448
449  // Called when the next commit should wait until the pending tree is activated
450  // before finishing the commit and unblocking the main thread. Used to ensure
451  // unused resources on the impl thread are returned before commit completes.
452  void SetNextCommitWaitsForActivation();
453
454  void SetNeedsPushProperties();
455  void AddDependentNeedsPushProperties();
456  void RemoveDependentNeedsPushProperties();
457  bool parent_should_know_need_push_properties() const {
458    return needs_push_properties() || descendant_needs_push_properties();
459  }
460
461  bool IsPropertyChangeAllowed() const;
462
463  // If this layer has a scroll parent, it removes |this| from its list of
464  // scroll children.
465  void RemoveFromScrollTree();
466
467  // If this layer has a clip parent, it removes |this| from its list of clip
468  // children.
469  void RemoveFromClipTree();
470
471  void reset_raster_scale_to_unknown() { raster_scale_ = 0.f; }
472
473  // This flag is set when the layer needs to push properties to the impl
474  // side.
475  bool needs_push_properties_;
476
477  // The number of direct children or dependent layers that need to be recursed
478  // to in order for them or a descendent of them to push properties to the impl
479  // side.
480  int num_dependents_need_push_properties_;
481
482  // Tracks whether this layer may have changed stacking order with its
483  // siblings.
484  bool stacking_order_changed_;
485
486  // The update rect is the region of the compositor resource that was
487  // actually updated by the compositor. For layers that may do updating
488  // outside the compositor's control (i.e. plugin layers), this information
489  // is not available and the update rect will remain empty.
490  // Note this rect is in layer space (not content space).
491  gfx::RectF update_rect_;
492
493  scoped_refptr<Layer> mask_layer_;
494
495  int layer_id_;
496
497  // When true, the layer is about to perform an update. Any commit requests
498  // will be handled implicitly after the update completes.
499  bool ignore_set_needs_commit_;
500
501 private:
502  friend class base::RefCounted<Layer>;
503
504  void SetParent(Layer* layer);
505  bool DescendantIsFixedToContainerLayer() const;
506
507  // Returns the index of the child or -1 if not found.
508  int IndexOfChild(const Layer* reference);
509
510  // This should only be called from RemoveFromParent().
511  void RemoveChildOrDependent(Layer* child);
512
513  // LayerAnimationValueObserver implementation.
514  virtual void OnOpacityAnimated(float opacity) OVERRIDE;
515  virtual void OnTransformAnimated(const gfx::Transform& transform) OVERRIDE;
516  virtual bool IsActive() const OVERRIDE;
517
518  LayerList children_;
519  Layer* parent_;
520
521  // Layer instances have a weak pointer to their LayerTreeHost.
522  // This pointer value is nil when a Layer is not in a tree and is
523  // updated via SetLayerTreeHost() if a layer moves between trees.
524  LayerTreeHost* layer_tree_host_;
525
526  scoped_refptr<LayerAnimationController> layer_animation_controller_;
527
528  // Layer properties.
529  gfx::Size bounds_;
530
531  gfx::Vector2d scroll_offset_;
532  gfx::Vector2d max_scroll_offset_;
533  bool scrollable_;
534  bool should_scroll_on_main_thread_;
535  bool have_wheel_event_handlers_;
536  Region non_fast_scrollable_region_;
537  Region touch_event_handler_region_;
538  gfx::PointF position_;
539  gfx::PointF anchor_point_;
540  SkColor background_color_;
541  CompositingReasons compositing_reasons_;
542  float opacity_;
543  FilterOperations filters_;
544  FilterOperations background_filters_;
545  float anchor_point_z_;
546  bool is_container_for_fixed_position_layers_;
547  LayerPositionConstraint position_constraint_;
548  bool is_drawable_;
549  bool hide_layer_and_subtree_;
550  bool masks_to_bounds_;
551  bool contents_opaque_;
552  bool double_sided_;
553  bool preserves_3d_;
554  bool use_parent_backface_visibility_;
555  bool draw_checkerboard_for_missing_tiles_;
556  bool force_render_surface_;
557  Layer* scroll_parent_;
558  scoped_ptr<std::set<Layer*> > scroll_children_;
559
560  Layer* clip_parent_;
561  scoped_ptr<std::set<Layer*> > clip_children_;
562
563  gfx::Transform transform_;
564  gfx::Transform sublayer_transform_;
565
566  // Replica layer used for reflections.
567  scoped_refptr<Layer> replica_layer_;
568
569  // Transient properties.
570  float raster_scale_;
571
572  LayerClient* client_;
573
574  ScopedPtrVector<CopyOutputRequest> copy_requests_;
575
576  base::Closure did_scroll_callback_;
577
578  DrawProperties<Layer, RenderSurface> draw_properties_;
579
580  PaintProperties paint_properties_;
581
582  DISALLOW_COPY_AND_ASSIGN(Layer);
583};
584
585}  // namespace cc
586
587#endif  // CC_LAYERS_LAYER_H_
588