layer.h revision 1e9bf3e0803691d0a228da41fc608347b6db4340 
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 "ui/gfx/rect.h"
33#include "ui/gfx/rect_f.h"
34#include "ui/gfx/transform.h"
35
36namespace gfx {
37class BoxF;
38}
39
40namespace cc {
41
42class Animation;
43class AnimationDelegate;
44struct AnimationEvent;
45class CopyOutputRequest;
46class LayerAnimationDelegate;
47class LayerAnimationEventObserver;
48class LayerClient;
49class LayerImpl;
50class LayerTreeHost;
51class LayerTreeImpl;
52class PriorityCalculator;
53class RenderingStatsInstrumentation;
54class ResourceUpdateQueue;
55class ScrollbarLayerInterface;
56struct AnimationEvent;
57
58// Base class for composited layers. Special layer types are derived from
59// this class.
60class CC_EXPORT Layer : public base::RefCounted<Layer>,
61                        public LayerAnimationValueObserver {
62 public:
63  typedef RenderSurfaceLayerList RenderSurfaceListType;
64  typedef LayerList LayerListType;
65  typedef RenderSurface RenderSurfaceType;
66
67  enum LayerIdLabels {
68    INVALID_ID = -1,
69  };
70
71  static scoped_refptr<Layer> Create();
72
73  int id() const { return layer_id_; }
74
75  Layer* RootLayer();
76  Layer* parent() { return parent_; }
77  const Layer* parent() const { return parent_; }
78  void AddChild(scoped_refptr<Layer> child);
79  void InsertChild(scoped_refptr<Layer> child, size_t index);
80  void ReplaceChild(Layer* reference, scoped_refptr<Layer> new_layer);
81  void RemoveFromParent();
82  void RemoveAllChildren();
83  void SetChildren(const LayerList& children);
84  bool HasAncestor(const Layer* ancestor) const;
85
86  const LayerList& children() const { return children_; }
87  Layer* child_at(size_t index) { return children_[index].get(); }
88
89  // This requests the layer and its subtree be rendered and given to the
90  // callback. If the copy is unable to be produced (the layer is destroyed
91  // first), then the callback is called with a NULL/empty result.
92  void RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> request);
93  bool HasCopyRequest() const {
94    return !copy_requests_.empty();
95  }
96
97  void SetAnchorPoint(gfx::PointF anchor_point);
98  gfx::PointF anchor_point() const { return anchor_point_; }
99
100  void SetAnchorPointZ(float anchor_point_z);
101  float anchor_point_z() const { return anchor_point_z_; }
102
103  virtual void SetBackgroundColor(SkColor background_color);
104  SkColor background_color() const { return background_color_; }
105  // If contents_opaque(), return an opaque color else return a
106  // non-opaque color.  Tries to return background_color(), if possible.
107  SkColor SafeOpaqueBackgroundColor() const;
108
109  // A layer's bounds are in logical, non-page-scaled pixels (however, the
110  // root layer's bounds are in physical pixels).
111  void SetBounds(gfx::Size bounds);
112  gfx::Size bounds() const { return bounds_; }
113
114  void SetMasksToBounds(bool masks_to_bounds);
115  bool masks_to_bounds() const { return masks_to_bounds_; }
116
117  void SetMaskLayer(Layer* mask_layer);
118  Layer* mask_layer() { return mask_layer_.get(); }
119  const Layer* mask_layer() const { return mask_layer_.get(); }
120
121  virtual void SetNeedsDisplayRect(const gfx::RectF& dirty_rect);
122  void SetNeedsDisplay() { SetNeedsDisplayRect(gfx::RectF(bounds())); }
123
124  void SetOpacity(float opacity);
125  float opacity() const { return opacity_; }
126  bool OpacityIsAnimating() const;
127  virtual bool OpacityCanAnimateOnImplThread() const;
128
129  void SetFilters(const FilterOperations& filters);
130  const FilterOperations& filters() const { return filters_; }
131  bool FilterIsAnimating() const;
132
133  // Background filters are filters applied to what is behind this layer, when
134  // they are viewed through non-opaque regions in this layer. They are used
135  // through the WebLayer interface, and are not exposed to HTML.
136  void SetBackgroundFilters(const FilterOperations& filters);
137  const FilterOperations& background_filters() const {
138    return background_filters_;
139  }
140
141  virtual void SetContentsOpaque(bool opaque);
142  bool contents_opaque() const { return contents_opaque_; }
143
144  void SetPosition(gfx::PointF position);
145  gfx::PointF position() const { return position_; }
146
147  void SetIsContainerForFixedPositionLayers(bool container);
148  bool IsContainerForFixedPositionLayers() const;
149
150  void SetPositionConstraint(const LayerPositionConstraint& constraint);
151  const LayerPositionConstraint& position_constraint() const {
152    return position_constraint_;
153  }
154
155  void SetSublayerTransform(const gfx::Transform& sublayer_transform);
156  const gfx::Transform& sublayer_transform() const {
157    return sublayer_transform_;
158  }
159
160  void SetTransform(const gfx::Transform& transform);
161  const gfx::Transform& transform() const { return transform_; }
162  bool TransformIsAnimating() const;
163
164  void SetScrollParent(Layer* parent);
165
166  Layer* scroll_parent() { return scroll_parent_; }
167  const Layer* scroll_parent() const { return scroll_parent_; }
168
169  void AddScrollChild(Layer* child);
170  void RemoveScrollChild(Layer* child);
171
172  std::set<Layer*>* scroll_children() { return scroll_children_.get(); }
173  const std::set<Layer*>* scroll_children() const {
174    return scroll_children_.get();
175  }
176
177  void SetClipParent(Layer* ancestor);
178
179  Layer* clip_parent() { return clip_parent_; }
180  const Layer* clip_parent() const {
181    return clip_parent_;
182  }
183
184  void AddClipChild(Layer* child);
185  void RemoveClipChild(Layer* child);
186
187  std::set<Layer*>* clip_children() { return clip_children_.get(); }
188  const std::set<Layer*>* clip_children() const {
189    return clip_children_.get();
190  }
191
192  DrawProperties<Layer>& draw_properties() { return draw_properties_; }
193  const DrawProperties<Layer>& draw_properties() const {
194    return draw_properties_;
195  }
196
197  // The following are shortcut accessors to get various information from
198  // draw_properties_
199  const gfx::Transform& draw_transform() const {
200    return draw_properties_.target_space_transform;
201  }
202  const gfx::Transform& screen_space_transform() const {
203    return draw_properties_.screen_space_transform;
204  }
205  float draw_opacity() const { return draw_properties_.opacity; }
206  bool draw_opacity_is_animating() const {
207    return draw_properties_.opacity_is_animating;
208  }
209  bool draw_transform_is_animating() const {
210    return draw_properties_.target_space_transform_is_animating;
211  }
212  bool screen_space_transform_is_animating() const {
213    return draw_properties_.screen_space_transform_is_animating;
214  }
215  bool screen_space_opacity_is_animating() const {
216    return draw_properties_.screen_space_opacity_is_animating;
217  }
218  bool can_use_lcd_text() const { return draw_properties_.can_use_lcd_text; }
219  bool is_clipped() const { return draw_properties_.is_clipped; }
220  gfx::Rect clip_rect() const { return draw_properties_.clip_rect; }
221  gfx::Rect drawable_content_rect() const {
222    return draw_properties_.drawable_content_rect;
223  }
224  gfx::Rect visible_content_rect() const {
225    return draw_properties_.visible_content_rect;
226  }
227  Layer* render_target() {
228    DCHECK(!draw_properties_.render_target ||
229           draw_properties_.render_target->render_surface());
230    return draw_properties_.render_target;
231  }
232  const Layer* render_target() const {
233    DCHECK(!draw_properties_.render_target ||
234           draw_properties_.render_target->render_surface());
235    return draw_properties_.render_target;
236  }
237  RenderSurface* render_surface() const {
238    return draw_properties_.render_surface.get();
239  }
240  int num_unclipped_descendants() const {
241    return draw_properties_.num_unclipped_descendants;
242  }
243
244  void SetScrollOffset(gfx::Vector2d scroll_offset);
245  gfx::Vector2d scroll_offset() const { return scroll_offset_; }
246  void SetScrollOffsetFromImplSide(gfx::Vector2d scroll_offset);
247
248  void SetMaxScrollOffset(gfx::Vector2d max_scroll_offset);
249  gfx::Vector2d max_scroll_offset() const { return max_scroll_offset_; }
250
251  void SetScrollable(bool scrollable);
252  bool scrollable() const { return scrollable_; }
253
254  void SetUserScrollable(bool horizontal, bool vertical);
255  bool user_scrollable_horizontal() const {
256    return user_scrollable_horizontal_;
257  }
258  bool user_scrollable_vertical() const { return user_scrollable_vertical_; }
259
260  void SetShouldScrollOnMainThread(bool should_scroll_on_main_thread);
261  bool should_scroll_on_main_thread() const {
262    return should_scroll_on_main_thread_;
263  }
264
265  void SetHaveWheelEventHandlers(bool have_wheel_event_handlers);
266  bool have_wheel_event_handlers() const { return have_wheel_event_handlers_; }
267
268  void SetNonFastScrollableRegion(const Region& non_fast_scrollable_region);
269  const Region& non_fast_scrollable_region() const {
270    return non_fast_scrollable_region_;
271  }
272
273  void SetTouchEventHandlerRegion(const Region& touch_event_handler_region);
274  const Region& touch_event_handler_region() const {
275    return touch_event_handler_region_;
276  }
277
278  void set_did_scroll_callback(const base::Closure& callback) {
279    did_scroll_callback_ = callback;
280  }
281
282  void SetDrawCheckerboardForMissingTiles(bool checkerboard);
283  bool DrawCheckerboardForMissingTiles() const {
284    return draw_checkerboard_for_missing_tiles_;
285  }
286
287  void SetForceRenderSurface(bool force_render_surface);
288  bool force_render_surface() const { return force_render_surface_; }
289
290  gfx::Vector2d ScrollDelta() const { return gfx::Vector2d(); }
291  gfx::Vector2dF TotalScrollOffset() const {
292    // Floating point to match the LayerImpl version.
293    return scroll_offset() + ScrollDelta();
294  }
295
296  void SetDoubleSided(bool double_sided);
297  bool double_sided() const { return double_sided_; }
298
299  void SetPreserves3d(bool preserves_3d) { preserves_3d_ = preserves_3d; }
300  bool preserves_3d() const { return preserves_3d_; }
301
302  void set_use_parent_backface_visibility(bool use) {
303    use_parent_backface_visibility_ = use;
304  }
305  bool use_parent_backface_visibility() const {
306    return use_parent_backface_visibility_;
307  }
308
309  virtual void SetLayerTreeHost(LayerTreeHost* host);
310
311  bool HasDelegatedContent() const { return false; }
312  bool HasContributingDelegatedRenderPasses() const { return false; }
313
314  void SetIsDrawable(bool is_drawable);
315
316  void SetHideLayerAndSubtree(bool hide);
317  bool hide_layer_and_subtree() const { return hide_layer_and_subtree_; }
318
319  void SetReplicaLayer(Layer* layer);
320  Layer* replica_layer() { return replica_layer_.get(); }
321  const Layer* replica_layer() const { return replica_layer_.get(); }
322
323  bool has_mask() const { return !!mask_layer_.get(); }
324  bool has_replica() const { return !!replica_layer_.get(); }
325  bool replica_has_mask() const {
326    return replica_layer_.get() &&
327           (mask_layer_.get() || replica_layer_->mask_layer_.get());
328  }
329
330  // These methods typically need to be overwritten by derived classes.
331  virtual bool DrawsContent() const;
332  virtual void SavePaintProperties();
333  // Returns true iff any resources were updated that need to be committed.
334  virtual bool Update(ResourceUpdateQueue* queue,
335                      const OcclusionTracker* occlusion);
336  virtual bool NeedMoreUpdates();
337  virtual void SetIsMask(bool is_mask) {}
338  virtual void ReduceMemoryUsage() {}
339  virtual void OnOutputSurfaceCreated() {}
340
341  virtual std::string DebugName();
342
343  void SetLayerClient(LayerClient* client) { client_ = client; }
344
345  void SetCompositingReasons(CompositingReasons reasons);
346
347  virtual void PushPropertiesTo(LayerImpl* layer);
348
349  void CreateRenderSurface();
350  void ClearRenderSurface();
351
352  // The contents scale converts from logical, non-page-scaled pixels to target
353  // pixels. The contents scale is 1 for the root layer as it is already in
354  // physical pixels. By default contents scale is forced to be 1 except for
355  // subclasses of ContentsScalingLayer.
356  float contents_scale_x() const { return draw_properties_.contents_scale_x; }
357  float contents_scale_y() const { return draw_properties_.contents_scale_y; }
358  gfx::Size content_bounds() const { return draw_properties_.content_bounds; }
359
360  virtual void CalculateContentsScale(float ideal_contents_scale,
361                                      float device_scale_factor,
362                                      float page_scale_factor,
363                                      bool animating_transform_to_screen,
364                                      float* contents_scale_x,
365                                      float* contents_scale_y,
366                                      gfx::Size* content_bounds);
367
368  LayerTreeHost* layer_tree_host() { return layer_tree_host_; }
369  const LayerTreeHost* layer_tree_host() const { return layer_tree_host_; }
370
371  // Set the priority of all desired textures in this layer.
372  virtual void SetTexturePriorities(const PriorityCalculator& priority_calc) {}
373
374  bool AddAnimation(scoped_ptr<Animation> animation);
375  void PauseAnimation(int animation_id, double time_offset);
376  void RemoveAnimation(int animation_id);
377
378  void SuspendAnimations(double monotonic_time);
379
380  bool AnimatedBoundsForBox(const gfx::BoxF& box, gfx::BoxF* bounds) {
381    return layer_animation_controller_->AnimatedBoundsForBox(box, bounds);
382  }
383
384  LayerAnimationController* layer_animation_controller() {
385    return layer_animation_controller_.get();
386  }
387  void SetLayerAnimationControllerForTest(
388      scoped_refptr<LayerAnimationController> controller);
389
390  void set_layer_animation_delegate(AnimationDelegate* delegate) {
391    layer_animation_controller_->set_layer_animation_delegate(delegate);
392  }
393
394  bool HasActiveAnimation() const;
395
396  void AddLayerAnimationEventObserver(
397      LayerAnimationEventObserver* animation_observer);
398  void RemoveLayerAnimationEventObserver(
399      LayerAnimationEventObserver* animation_observer);
400
401  virtual Region VisibleContentOpaqueRegion() const;
402
403  virtual ScrollbarLayerInterface* ToScrollbarLayer();
404
405  gfx::Rect LayerRectToContentRect(const gfx::RectF& layer_rect) const;
406
407  virtual skia::RefPtr<SkPicture> GetPicture() const;
408
409  // Constructs a LayerImpl of the correct runtime type for this Layer type.
410  virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl);
411
412  bool NeedsDisplayForTesting() const { return !update_rect_.IsEmpty(); }
413  void ResetNeedsDisplayForTesting() { update_rect_ = gfx::RectF(); }
414
415  RenderingStatsInstrumentation* rendering_stats_instrumentation() const;
416
417  const PaintProperties& paint_properties() const {
418    return paint_properties_;
419  }
420
421  // The scale at which contents should be rastered, to match the scale at
422  // which they will drawn to the screen. This scale is a component of the
423  // contents scale but does not include page/device scale factors.
424  // TODO(danakj): This goes away when TiledLayer goes away.
425  void set_raster_scale(float scale) { raster_scale_ = scale; }
426  float raster_scale() const { return raster_scale_; }
427  bool raster_scale_is_unknown() const { return raster_scale_ == 0.f; }
428
429  virtual bool SupportsLCDText() const;
430
431  bool needs_push_properties() const { return needs_push_properties_; }
432  bool descendant_needs_push_properties() const {
433    return num_dependents_need_push_properties_ > 0;
434  }
435
436  virtual void RunMicroBenchmark(MicroBenchmark* benchmark);
437
438 protected:
439  friend class LayerImpl;
440  friend class TreeSynchronizer;
441  virtual ~Layer();
442
443  Layer();
444
445  // These SetNeeds functions are in order of severity of update:
446  //
447  // Called when this layer has been modified in some way, but isn't sure
448  // that it needs a commit yet.  It needs CalcDrawProperties and UpdateLayers
449  // before it knows whether or not a commit is required.
450  void SetNeedsUpdate();
451  // Called when a property has been modified in a way that the layer
452  // knows immediately that a commit is required.  This implies SetNeedsUpdate
453  // as well as SetNeedsPushProperties to push that property.
454  void SetNeedsCommit();
455  // Called when there's been a change in layer structure.  Implies both
456  // SetNeedsUpdate and SetNeedsCommit, but not SetNeedsPushProperties.
457  void SetNeedsFullTreeSync();
458
459  // Called when the next commit should wait until the pending tree is activated
460  // before finishing the commit and unblocking the main thread. Used to ensure
461  // unused resources on the impl thread are returned before commit completes.
462  void SetNextCommitWaitsForActivation();
463
464  void SetNeedsPushProperties();
465  void AddDependentNeedsPushProperties();
466  void RemoveDependentNeedsPushProperties();
467  bool parent_should_know_need_push_properties() const {
468    return needs_push_properties() || descendant_needs_push_properties();
469  }
470
471  bool IsPropertyChangeAllowed() const;
472
473  // If this layer has a scroll parent, it removes |this| from its list of
474  // scroll children.
475  void RemoveFromScrollTree();
476
477  // If this layer has a clip parent, it removes |this| from its list of clip
478  // children.
479  void RemoveFromClipTree();
480
481  void reset_raster_scale_to_unknown() { raster_scale_ = 0.f; }
482
483  // This flag is set when the layer needs to push properties to the impl
484  // side.
485  bool needs_push_properties_;
486
487  // The number of direct children or dependent layers that need to be recursed
488  // to in order for them or a descendent of them to push properties to the impl
489  // side.
490  int num_dependents_need_push_properties_;
491
492  // Tracks whether this layer may have changed stacking order with its
493  // siblings.
494  bool stacking_order_changed_;
495
496  // The update rect is the region of the compositor resource that was
497  // actually updated by the compositor. For layers that may do updating
498  // outside the compositor's control (i.e. plugin layers), this information
499  // is not available and the update rect will remain empty.
500  // Note this rect is in layer space (not content space).
501  gfx::RectF update_rect_;
502
503  scoped_refptr<Layer> mask_layer_;
504
505  int layer_id_;
506
507  // When true, the layer is about to perform an update. Any commit requests
508  // will be handled implicitly after the update completes.
509  bool ignore_set_needs_commit_;
510
511 private:
512  friend class base::RefCounted<Layer>;
513
514  void SetParent(Layer* layer);
515  bool DescendantIsFixedToContainerLayer() const;
516
517  // Returns the index of the child or -1 if not found.
518  int IndexOfChild(const Layer* reference);
519
520  // This should only be called from RemoveFromParent().
521  void RemoveChildOrDependent(Layer* child);
522
523  // LayerAnimationValueObserver implementation.
524  virtual void OnFilterAnimated(const FilterOperations& filters) OVERRIDE;
525  virtual void OnOpacityAnimated(float opacity) OVERRIDE;
526  virtual void OnTransformAnimated(const gfx::Transform& transform) OVERRIDE;
527  virtual bool IsActive() const OVERRIDE;
528
529  LayerList children_;
530  Layer* parent_;
531
532  // Layer instances have a weak pointer to their LayerTreeHost.
533  // This pointer value is nil when a Layer is not in a tree and is
534  // updated via SetLayerTreeHost() if a layer moves between trees.
535  LayerTreeHost* layer_tree_host_;
536
537  scoped_refptr<LayerAnimationController> layer_animation_controller_;
538
539  // Layer properties.
540  gfx::Size bounds_;
541
542  gfx::Vector2d scroll_offset_;
543  gfx::Vector2d max_scroll_offset_;
544  bool scrollable_;
545  bool should_scroll_on_main_thread_;
546  bool have_wheel_event_handlers_;
547  bool user_scrollable_horizontal_;
548  bool user_scrollable_vertical_;
549  Region non_fast_scrollable_region_;
550  Region touch_event_handler_region_;
551  gfx::PointF position_;
552  gfx::PointF anchor_point_;
553  SkColor background_color_;
554  CompositingReasons compositing_reasons_;
555  float opacity_;
556  FilterOperations filters_;
557  FilterOperations background_filters_;
558  float anchor_point_z_;
559  bool is_container_for_fixed_position_layers_;
560  LayerPositionConstraint position_constraint_;
561  bool is_drawable_;
562  bool hide_layer_and_subtree_;
563  bool masks_to_bounds_;
564  bool contents_opaque_;
565  bool double_sided_;
566  bool preserves_3d_;
567  bool use_parent_backface_visibility_;
568  bool draw_checkerboard_for_missing_tiles_;
569  bool force_render_surface_;
570  Layer* scroll_parent_;
571  scoped_ptr<std::set<Layer*> > scroll_children_;
572
573  Layer* clip_parent_;
574  scoped_ptr<std::set<Layer*> > clip_children_;
575
576  gfx::Transform transform_;
577  gfx::Transform sublayer_transform_;
578
579  // Replica layer used for reflections.
580  scoped_refptr<Layer> replica_layer_;
581
582  // Transient properties.
583  float raster_scale_;
584
585  LayerClient* client_;
586
587  ScopedPtrVector<CopyOutputRequest> copy_requests_;
588
589  base::Closure did_scroll_callback_;
590
591  DrawProperties<Layer> draw_properties_;
592
593  PaintProperties paint_properties_;
594
595  DISALLOW_COPY_AND_ASSIGN(Layer);
596};
597
598}  // namespace cc
599
600#endif  // CC_LAYERS_LAYER_H_
601