layer.h revision 46d4c2bc3267f3f028f39e7e311b0f89aba2e4fd 
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/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/debug/micro_benchmark.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 "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 "third_party/skia/include/core/SkXfermode.h"
32#include "ui/gfx/point3_f.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 base {
42namespace debug {
43class ConvertableToTraceFormat;
44}
45}
46
47namespace cc {
48
49class Animation;
50class AnimationDelegate;
51struct AnimationEvent;
52class CopyOutputRequest;
53class LayerAnimationDelegate;
54class LayerAnimationEventObserver;
55class LayerClient;
56class LayerImpl;
57class LayerTreeHost;
58class LayerTreeImpl;
59class PriorityCalculator;
60class RenderingStatsInstrumentation;
61class ResourceUpdateQueue;
62class ScrollbarLayerInterface;
63struct AnimationEvent;
64template <typename LayerType>
65class OcclusionTracker;
66
67// Base class for composited layers. Special layer types are derived from
68// this class.
69class CC_EXPORT Layer : public base::RefCounted<Layer>,
70                        public LayerAnimationValueObserver,
71                        public LayerAnimationValueProvider {
72 public:
73  typedef RenderSurfaceLayerList RenderSurfaceListType;
74  typedef LayerList LayerListType;
75  typedef RenderSurface RenderSurfaceType;
76
77  enum LayerIdLabels {
78    INVALID_ID = -1,
79  };
80
81  static scoped_refptr<Layer> Create();
82
83  int id() const { return layer_id_; }
84
85  Layer* RootLayer();
86  Layer* parent() { return parent_; }
87  const Layer* parent() const { return parent_; }
88  void AddChild(scoped_refptr<Layer> child);
89  void InsertChild(scoped_refptr<Layer> child, size_t index);
90  void ReplaceChild(Layer* reference, scoped_refptr<Layer> new_layer);
91  void RemoveFromParent();
92  void RemoveAllChildren();
93  void SetChildren(const LayerList& children);
94  bool HasAncestor(const Layer* ancestor) const;
95
96  const LayerList& children() const { return children_; }
97  Layer* child_at(size_t index) { return children_[index].get(); }
98
99  // This requests the layer and its subtree be rendered and given to the
100  // callback. If the copy is unable to be produced (the layer is destroyed
101  // first), then the callback is called with a NULL/empty result.
102  void RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> request);
103  bool HasCopyRequest() const {
104    return !copy_requests_.empty();
105  }
106
107  virtual void SetBackgroundColor(SkColor background_color);
108  SkColor background_color() const { return background_color_; }
109  // If contents_opaque(), return an opaque color else return a
110  // non-opaque color.  Tries to return background_color(), if possible.
111  SkColor SafeOpaqueBackgroundColor() const;
112
113  // A layer's bounds are in logical, non-page-scaled pixels (however, the
114  // root layer's bounds are in physical pixels).
115  void SetBounds(const gfx::Size& bounds);
116  gfx::Size bounds() const { return bounds_; }
117
118  void SetMasksToBounds(bool masks_to_bounds);
119  bool masks_to_bounds() const { return masks_to_bounds_; }
120
121  void SetMaskLayer(Layer* mask_layer);
122  Layer* mask_layer() { return mask_layer_.get(); }
123  const Layer* mask_layer() const { return mask_layer_.get(); }
124
125  virtual void SetNeedsDisplayRect(const gfx::RectF& dirty_rect);
126  void SetNeedsDisplay() { SetNeedsDisplayRect(gfx::RectF(bounds())); }
127
128  void SetOpacity(float opacity);
129  float opacity() const { return opacity_; }
130  bool OpacityIsAnimating() const;
131  virtual bool OpacityCanAnimateOnImplThread() const;
132
133  void SetBlendMode(SkXfermode::Mode blend_mode);
134  SkXfermode::Mode blend_mode() const { return blend_mode_; }
135
136  bool uses_default_blend_mode() const {
137    return blend_mode_ == SkXfermode::kSrcOver_Mode;
138  }
139
140  // A layer is root for an isolated group when it and all its descendants are
141  // drawn over a black and fully transparent background, creating an isolated
142  // group. It should be used along with SetBlendMode(), in order to restrict
143  // layers within the group to blend with layers outside this group.
144  void SetIsRootForIsolatedGroup(bool root);
145  bool is_root_for_isolated_group() const {
146    return is_root_for_isolated_group_;
147  }
148
149  void SetFilters(const FilterOperations& filters);
150  const FilterOperations& filters() const { return filters_; }
151  bool FilterIsAnimating() const;
152
153  // Background filters are filters applied to what is behind this layer, when
154  // they are viewed through non-opaque regions in this layer. They are used
155  // through the WebLayer interface, and are not exposed to HTML.
156  void SetBackgroundFilters(const FilterOperations& filters);
157  const FilterOperations& background_filters() const {
158    return background_filters_;
159  }
160
161  virtual void SetContentsOpaque(bool opaque);
162  bool contents_opaque() const { return contents_opaque_; }
163
164  void SetPosition(const gfx::PointF& position);
165  gfx::PointF position() const { return position_; }
166
167  void SetIsContainerForFixedPositionLayers(bool container);
168  bool IsContainerForFixedPositionLayers() const;
169
170  void SetPositionConstraint(const LayerPositionConstraint& constraint);
171  const LayerPositionConstraint& position_constraint() const {
172    return position_constraint_;
173  }
174
175  void SetTransform(const gfx::Transform& transform);
176  const gfx::Transform& transform() const { return transform_; }
177  bool TransformIsAnimating() const;
178  bool transform_is_invertible() const { return transform_is_invertible_; }
179
180  void SetTransformOrigin(const gfx::Point3F&);
181  gfx::Point3F transform_origin() { return transform_origin_; }
182
183  void SetScrollParent(Layer* parent);
184
185  Layer* scroll_parent() { return scroll_parent_; }
186  const Layer* scroll_parent() const { return scroll_parent_; }
187
188  void AddScrollChild(Layer* child);
189  void RemoveScrollChild(Layer* child);
190
191  std::set<Layer*>* scroll_children() { return scroll_children_.get(); }
192  const std::set<Layer*>* scroll_children() const {
193    return scroll_children_.get();
194  }
195
196  void SetClipParent(Layer* ancestor);
197
198  Layer* clip_parent() { return clip_parent_; }
199  const Layer* clip_parent() const {
200    return clip_parent_;
201  }
202
203  void AddClipChild(Layer* child);
204  void RemoveClipChild(Layer* child);
205
206  std::set<Layer*>* clip_children() { return clip_children_.get(); }
207  const std::set<Layer*>* clip_children() const {
208    return clip_children_.get();
209  }
210
211  DrawProperties<Layer>& draw_properties() { return draw_properties_; }
212  const DrawProperties<Layer>& draw_properties() const {
213    return draw_properties_;
214  }
215
216  // The following are shortcut accessors to get various information from
217  // draw_properties_
218  const gfx::Transform& draw_transform() const {
219    return draw_properties_.target_space_transform;
220  }
221  const gfx::Transform& screen_space_transform() const {
222    return draw_properties_.screen_space_transform;
223  }
224  float draw_opacity() const { return draw_properties_.opacity; }
225  bool draw_opacity_is_animating() const {
226    return draw_properties_.opacity_is_animating;
227  }
228  bool draw_transform_is_animating() const {
229    return draw_properties_.target_space_transform_is_animating;
230  }
231  bool screen_space_transform_is_animating() const {
232    return draw_properties_.screen_space_transform_is_animating;
233  }
234  bool screen_space_opacity_is_animating() const {
235    return draw_properties_.screen_space_opacity_is_animating;
236  }
237  bool can_use_lcd_text() const { return draw_properties_.can_use_lcd_text; }
238  bool is_clipped() const { return draw_properties_.is_clipped; }
239  gfx::Rect clip_rect() const { return draw_properties_.clip_rect; }
240  gfx::Rect drawable_content_rect() const {
241    return draw_properties_.drawable_content_rect;
242  }
243  gfx::Rect visible_content_rect() const {
244    return draw_properties_.visible_content_rect;
245  }
246  Layer* render_target() {
247    DCHECK(!draw_properties_.render_target ||
248           draw_properties_.render_target->render_surface());
249    return draw_properties_.render_target;
250  }
251  const Layer* render_target() const {
252    DCHECK(!draw_properties_.render_target ||
253           draw_properties_.render_target->render_surface());
254    return draw_properties_.render_target;
255  }
256  RenderSurface* render_surface() const {
257    return draw_properties_.render_surface.get();
258  }
259  int num_unclipped_descendants() const {
260    return draw_properties_.num_unclipped_descendants;
261  }
262
263  void SetScrollOffset(gfx::Vector2d scroll_offset);
264  gfx::Vector2d scroll_offset() const { return scroll_offset_; }
265  void SetScrollOffsetFromImplSide(const gfx::Vector2d& scroll_offset);
266
267  void SetScrollClipLayerId(int clip_layer_id);
268  bool scrollable() const { return scroll_clip_layer_id_ != INVALID_ID; }
269
270  void SetUserScrollable(bool horizontal, bool vertical);
271  bool user_scrollable_horizontal() const {
272    return user_scrollable_horizontal_;
273  }
274  bool user_scrollable_vertical() const { return user_scrollable_vertical_; }
275
276  void SetShouldScrollOnMainThread(bool should_scroll_on_main_thread);
277  bool should_scroll_on_main_thread() const {
278    return should_scroll_on_main_thread_;
279  }
280
281  void SetHaveWheelEventHandlers(bool have_wheel_event_handlers);
282  bool have_wheel_event_handlers() const { return have_wheel_event_handlers_; }
283
284  void SetHaveScrollEventHandlers(bool have_scroll_event_handlers);
285  bool have_scroll_event_handlers() const {
286    return have_scroll_event_handlers_;
287  }
288
289  void SetNonFastScrollableRegion(const Region& non_fast_scrollable_region);
290  const Region& non_fast_scrollable_region() const {
291    return non_fast_scrollable_region_;
292  }
293
294  void SetTouchEventHandlerRegion(const Region& touch_event_handler_region);
295  const Region& touch_event_handler_region() const {
296    return touch_event_handler_region_;
297  }
298
299  void set_did_scroll_callback(const base::Closure& callback) {
300    did_scroll_callback_ = callback;
301  }
302
303  void SetDrawCheckerboardForMissingTiles(bool checkerboard);
304  bool draw_checkerboard_for_missing_tiles() const {
305    return draw_checkerboard_for_missing_tiles_;
306  }
307
308  void SetForceRenderSurface(bool force_render_surface);
309  bool force_render_surface() const { return force_render_surface_; }
310
311  gfx::Vector2d ScrollDelta() const { return gfx::Vector2d(); }
312  gfx::Vector2dF TotalScrollOffset() const {
313    // Floating point to match the LayerImpl version.
314    return scroll_offset() + ScrollDelta();
315  }
316
317  void SetDoubleSided(bool double_sided);
318  bool double_sided() const { return double_sided_; }
319
320  void SetShouldFlattenTransform(bool flatten);
321  bool should_flatten_transform() const { return should_flatten_transform_; }
322
323  void SetIs3dSorted(bool sorted);
324  bool is_3d_sorted() const { return is_3d_sorted_; }
325
326  void set_use_parent_backface_visibility(bool use) {
327    use_parent_backface_visibility_ = use;
328  }
329  bool use_parent_backface_visibility() const {
330    return use_parent_backface_visibility_;
331  }
332
333  virtual void SetLayerTreeHost(LayerTreeHost* host);
334
335  bool HasDelegatedContent() const { return false; }
336  bool HasContributingDelegatedRenderPasses() const { return false; }
337
338  void SetIsDrawable(bool is_drawable);
339
340  void SetHideLayerAndSubtree(bool hide);
341  bool hide_layer_and_subtree() const { return hide_layer_and_subtree_; }
342
343  void SetReplicaLayer(Layer* layer);
344  Layer* replica_layer() { return replica_layer_.get(); }
345  const Layer* replica_layer() const { return replica_layer_.get(); }
346
347  bool has_mask() const { return !!mask_layer_.get(); }
348  bool has_replica() const { return !!replica_layer_.get(); }
349  bool replica_has_mask() const {
350    return replica_layer_.get() &&
351           (mask_layer_.get() || replica_layer_->mask_layer_.get());
352  }
353
354  // These methods typically need to be overwritten by derived classes.
355  virtual bool DrawsContent() const;
356  virtual void SavePaintProperties();
357  // Returns true iff any resources were updated that need to be committed.
358  virtual bool Update(ResourceUpdateQueue* queue,
359                      const OcclusionTracker<Layer>* occlusion);
360  virtual bool NeedMoreUpdates();
361  virtual void SetIsMask(bool is_mask) {}
362  virtual void ReduceMemoryUsage() {}
363  virtual void OnOutputSurfaceCreated() {}
364  virtual bool IsSuitableForGpuRasterization() const;
365
366  virtual scoped_refptr<base::debug::ConvertableToTraceFormat> TakeDebugInfo();
367
368  void SetLayerClient(LayerClient* client) { client_ = client; }
369
370  virtual void PushPropertiesTo(LayerImpl* layer);
371
372  void CreateRenderSurface();
373  void ClearRenderSurface();
374  void ClearRenderSurfaceLayerList();
375
376  // The contents scale converts from logical, non-page-scaled pixels to target
377  // pixels. The contents scale is 1 for the root layer as it is already in
378  // physical pixels. By default contents scale is forced to be 1 except for
379  // subclasses of ContentsScalingLayer.
380  float contents_scale_x() const { return draw_properties_.contents_scale_x; }
381  float contents_scale_y() const { return draw_properties_.contents_scale_y; }
382  gfx::Size content_bounds() const { return draw_properties_.content_bounds; }
383
384  virtual void CalculateContentsScale(float ideal_contents_scale,
385                                      float device_scale_factor,
386                                      float page_scale_factor,
387                                      float maximum_animation_contents_scale,
388                                      bool animating_transform_to_screen,
389                                      float* contents_scale_x,
390                                      float* contents_scale_y,
391                                      gfx::Size* content_bounds);
392
393  LayerTreeHost* layer_tree_host() { return layer_tree_host_; }
394  const LayerTreeHost* layer_tree_host() const { return layer_tree_host_; }
395
396  // Set the priority of all desired textures in this layer.
397  virtual void SetTexturePriorities(const PriorityCalculator& priority_calc) {}
398
399  bool AddAnimation(scoped_ptr<Animation> animation);
400  void PauseAnimation(int animation_id, double time_offset);
401  void RemoveAnimation(int animation_id);
402
403  LayerAnimationController* layer_animation_controller() {
404    return layer_animation_controller_.get();
405  }
406  void SetLayerAnimationControllerForTest(
407      scoped_refptr<LayerAnimationController> controller);
408
409  void set_layer_animation_delegate(AnimationDelegate* delegate) {
410    layer_animation_controller_->set_layer_animation_delegate(delegate);
411  }
412
413  bool HasActiveAnimation() const;
414
415  void AddLayerAnimationEventObserver(
416      LayerAnimationEventObserver* animation_observer);
417  void RemoveLayerAnimationEventObserver(
418      LayerAnimationEventObserver* animation_observer);
419
420  virtual Region VisibleContentOpaqueRegion() const;
421
422  virtual ScrollbarLayerInterface* ToScrollbarLayer();
423
424  gfx::Rect LayerRectToContentRect(const gfx::RectF& layer_rect) const;
425
426  virtual skia::RefPtr<SkPicture> GetPicture() const;
427
428  // Constructs a LayerImpl of the correct runtime type for this Layer type.
429  virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl);
430
431  bool NeedsDisplayForTesting() const { return !update_rect_.IsEmpty(); }
432  void ResetNeedsDisplayForTesting() { update_rect_ = gfx::RectF(); }
433
434  RenderingStatsInstrumentation* rendering_stats_instrumentation() const;
435
436  const PaintProperties& paint_properties() const {
437    return paint_properties_;
438  }
439
440  // The scale at which contents should be rastered, to match the scale at
441  // which they will drawn to the screen. This scale is a component of the
442  // contents scale but does not include page/device scale factors.
443  // TODO(danakj): This goes away when TiledLayer goes away.
444  void set_raster_scale(float scale) { raster_scale_ = scale; }
445  float raster_scale() const { return raster_scale_; }
446  bool raster_scale_is_unknown() const { return raster_scale_ == 0.f; }
447
448  virtual bool SupportsLCDText() const;
449
450  void SetNeedsPushProperties();
451  bool needs_push_properties() const { return needs_push_properties_; }
452  bool descendant_needs_push_properties() const {
453    return num_dependents_need_push_properties_ > 0;
454  }
455  void reset_needs_push_properties_for_testing() {
456    needs_push_properties_ = false;
457  }
458
459  virtual void RunMicroBenchmark(MicroBenchmark* benchmark);
460
461 protected:
462  friend class LayerImpl;
463  friend class TreeSynchronizer;
464  virtual ~Layer();
465
466  Layer();
467
468  // These SetNeeds functions are in order of severity of update:
469  //
470  // Called when this layer has been modified in some way, but isn't sure
471  // that it needs a commit yet.  It needs CalcDrawProperties and UpdateLayers
472  // before it knows whether or not a commit is required.
473  void SetNeedsUpdate();
474  // Called when a property has been modified in a way that the layer
475  // knows immediately that a commit is required.  This implies SetNeedsUpdate
476  // as well as SetNeedsPushProperties to push that property.
477  void SetNeedsCommit();
478  // Called when there's been a change in layer structure.  Implies both
479  // SetNeedsUpdate and SetNeedsCommit, but not SetNeedsPushProperties.
480  void SetNeedsFullTreeSync();
481
482  // Called when the next commit should wait until the pending tree is activated
483  // before finishing the commit and unblocking the main thread. Used to ensure
484  // unused resources on the impl thread are returned before commit completes.
485  void SetNextCommitWaitsForActivation();
486
487  void AddDependentNeedsPushProperties();
488  void RemoveDependentNeedsPushProperties();
489  bool parent_should_know_need_push_properties() const {
490    return needs_push_properties() || descendant_needs_push_properties();
491  }
492
493  bool IsPropertyChangeAllowed() const;
494
495  // If this layer has a scroll parent, it removes |this| from its list of
496  // scroll children.
497  void RemoveFromScrollTree();
498
499  // If this layer has a clip parent, it removes |this| from its list of clip
500  // children.
501  void RemoveFromClipTree();
502
503  void reset_raster_scale_to_unknown() { raster_scale_ = 0.f; }
504
505  // This flag is set when the layer needs to push properties to the impl
506  // side.
507  bool needs_push_properties_;
508
509  // The number of direct children or dependent layers that need to be recursed
510  // to in order for them or a descendent of them to push properties to the impl
511  // side.
512  int num_dependents_need_push_properties_;
513
514  // Tracks whether this layer may have changed stacking order with its
515  // siblings.
516  bool stacking_order_changed_;
517
518  // The update rect is the region of the compositor resource that was
519  // actually updated by the compositor. For layers that may do updating
520  // outside the compositor's control (i.e. plugin layers), this information
521  // is not available and the update rect will remain empty.
522  // Note this rect is in layer space (not content space).
523  gfx::RectF update_rect_;
524
525  scoped_refptr<Layer> mask_layer_;
526
527  int layer_id_;
528
529  // When true, the layer is about to perform an update. Any commit requests
530  // will be handled implicitly after the update completes.
531  bool ignore_set_needs_commit_;
532
533 private:
534  friend class base::RefCounted<Layer>;
535
536  void SetParent(Layer* layer);
537  bool DescendantIsFixedToContainerLayer() const;
538
539  // Returns the index of the child or -1 if not found.
540  int IndexOfChild(const Layer* reference);
541
542  // This should only be called from RemoveFromParent().
543  void RemoveChildOrDependent(Layer* child);
544
545  // LayerAnimationValueProvider implementation.
546  virtual gfx::Vector2dF ScrollOffsetForAnimation() const OVERRIDE;
547
548  // LayerAnimationValueObserver implementation.
549  virtual void OnFilterAnimated(const FilterOperations& filters) OVERRIDE;
550  virtual void OnOpacityAnimated(float opacity) OVERRIDE;
551  virtual void OnTransformAnimated(const gfx::Transform& transform) OVERRIDE;
552  virtual void OnScrollOffsetAnimated(
553      const gfx::Vector2dF& scroll_offset) OVERRIDE;
554  virtual void OnAnimationWaitingForDeletion() OVERRIDE;
555  virtual bool IsActive() const OVERRIDE;
556
557  LayerList children_;
558  Layer* parent_;
559
560  // Layer instances have a weak pointer to their LayerTreeHost.
561  // This pointer value is nil when a Layer is not in a tree and is
562  // updated via SetLayerTreeHost() if a layer moves between trees.
563  LayerTreeHost* layer_tree_host_;
564
565  scoped_refptr<LayerAnimationController> layer_animation_controller_;
566
567  // Layer properties.
568  gfx::Size bounds_;
569
570  gfx::Vector2d scroll_offset_;
571  // This variable indicates which ancestor layer (if any) whose size,
572  // transformed relative to this layer, defines the maximum scroll offset for
573  // this layer.
574  int scroll_clip_layer_id_;
575  bool should_scroll_on_main_thread_ : 1;
576  bool have_wheel_event_handlers_ : 1;
577  bool have_scroll_event_handlers_ : 1;
578  bool user_scrollable_horizontal_ : 1;
579  bool user_scrollable_vertical_ : 1;
580  bool is_root_for_isolated_group_ : 1;
581  bool is_container_for_fixed_position_layers_ : 1;
582  bool is_drawable_ : 1;
583  bool hide_layer_and_subtree_ : 1;
584  bool masks_to_bounds_ : 1;
585  bool contents_opaque_ : 1;
586  bool double_sided_ : 1;
587  bool should_flatten_transform_ : 1;
588  bool use_parent_backface_visibility_ : 1;
589  bool draw_checkerboard_for_missing_tiles_ : 1;
590  bool force_render_surface_ : 1;
591  bool is_3d_sorted_ : 1;
592  bool transform_is_invertible_ : 1;
593  Region non_fast_scrollable_region_;
594  Region touch_event_handler_region_;
595  gfx::PointF position_;
596  SkColor background_color_;
597  float opacity_;
598  SkXfermode::Mode blend_mode_;
599  FilterOperations filters_;
600  FilterOperations background_filters_;
601  LayerPositionConstraint position_constraint_;
602  Layer* scroll_parent_;
603  scoped_ptr<std::set<Layer*> > scroll_children_;
604
605  Layer* clip_parent_;
606  scoped_ptr<std::set<Layer*> > clip_children_;
607
608  gfx::Transform transform_;
609  gfx::Point3F transform_origin_;
610
611  // Replica layer used for reflections.
612  scoped_refptr<Layer> replica_layer_;
613
614  // Transient properties.
615  float raster_scale_;
616
617  LayerClient* client_;
618
619  ScopedPtrVector<CopyOutputRequest> copy_requests_;
620
621  base::Closure did_scroll_callback_;
622
623  DrawProperties<Layer> draw_properties_;
624
625  PaintProperties paint_properties_;
626
627  DISALLOW_COPY_AND_ASSIGN(Layer);
628};
629
630}  // namespace cc
631
632#endif  // CC_LAYERS_LAYER_H_
633