picture_layer.cc revision a02191e04bc25c4935f804f2c080ae28663d096d 
1// Copyright 2012 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#include "cc/layers/picture_layer.h"
6
7#include "cc/layers/content_layer_client.h"
8#include "cc/layers/picture_layer_impl.h"
9#include "cc/trees/layer_tree_impl.h"
10#include "ui/gfx/rect_conversions.h"
11
12namespace cc {
13
14scoped_refptr<PictureLayer> PictureLayer::Create(ContentLayerClient* client) {
15  return make_scoped_refptr(new PictureLayer(client));
16}
17
18PictureLayer::PictureLayer(ContentLayerClient* client)
19    : client_(client),
20      pile_(make_scoped_refptr(new PicturePile())),
21      instrumentation_object_tracker_(id()),
22      is_mask_(false),
23      has_gpu_rasterization_hint_(TRIBOOL_UNKNOWN),
24      update_source_frame_number_(-1) {}
25
26PictureLayer::~PictureLayer() {
27}
28
29bool PictureLayer::DrawsContent() const {
30  return Layer::DrawsContent() && client_;
31}
32
33scoped_ptr<LayerImpl> PictureLayer::CreateLayerImpl(LayerTreeImpl* tree_impl) {
34  return PictureLayerImpl::Create(tree_impl, id()).PassAs<LayerImpl>();
35}
36
37void PictureLayer::PushPropertiesTo(LayerImpl* base_layer) {
38  Layer::PushPropertiesTo(base_layer);
39  PictureLayerImpl* layer_impl = static_cast<PictureLayerImpl*>(base_layer);
40
41  if (layer_impl->bounds().IsEmpty()) {
42    // Update may not get called for an empty layer, so resize here instead.
43    // Using layer_impl because either bounds() or paint_properties().bounds
44    // may disagree and either one could have been pushed to layer_impl.
45    pile_->Resize(gfx::Size());
46  } else if (update_source_frame_number_ ==
47             layer_tree_host()->source_frame_number()) {
48    // If update called, then pile size must match bounds pushed to impl layer.
49    DCHECK_EQ(layer_impl->bounds().ToString(), pile_->size().ToString());
50  }
51
52  layer_impl->SetIsMask(is_mask_);
53  layer_impl->SetUseGpuRasterization(ShouldUseGpuRasterization());
54
55  // Unlike other properties, invalidation must always be set on layer_impl.
56  // See PictureLayerImpl::PushPropertiesTo for more details.
57  layer_impl->invalidation_.Clear();
58  layer_impl->invalidation_.Swap(&pile_invalidation_);
59  layer_impl->pile_ = PicturePileImpl::CreateFromOther(pile_.get());
60}
61
62void PictureLayer::SetLayerTreeHost(LayerTreeHost* host) {
63  Layer::SetLayerTreeHost(host);
64  if (host) {
65    pile_->SetMinContentsScale(host->settings().minimum_contents_scale);
66    pile_->SetTileGridSize(host->settings().default_tile_size);
67    pile_->set_slow_down_raster_scale_factor(
68        host->debug_state().slow_down_raster_scale_factor);
69    pile_->set_show_debug_picture_borders(
70        host->debug_state().show_picture_borders);
71  }
72}
73
74void PictureLayer::SetNeedsDisplayRect(const gfx::RectF& layer_rect) {
75  gfx::Rect rect = gfx::ToEnclosedRect(layer_rect);
76  if (!rect.IsEmpty()) {
77    // Clamp invalidation to the layer bounds.
78    rect.Intersect(gfx::Rect(bounds()));
79    pending_invalidation_.Union(rect);
80  }
81  Layer::SetNeedsDisplayRect(layer_rect);
82}
83
84bool PictureLayer::Update(ResourceUpdateQueue* queue,
85                          const OcclusionTracker<Layer>* occlusion) {
86  update_source_frame_number_ = layer_tree_host()->source_frame_number();
87  bool updated = Layer::Update(queue, occlusion);
88
89  if (last_updated_visible_content_rect_ == visible_content_rect() &&
90      pile_->size() == paint_properties().bounds &&
91      pending_invalidation_.IsEmpty()) {
92    // Only early out if the visible content rect of this layer hasn't changed.
93    return updated;
94  }
95
96  TRACE_EVENT1("cc", "PictureLayer::Update",
97               "source_frame_number",
98               layer_tree_host()->source_frame_number());
99
100  pile_->Resize(paint_properties().bounds);
101
102  // Calling paint in WebKit can sometimes cause invalidations, so save
103  // off the invalidation prior to calling update.
104  pending_invalidation_.Swap(&pile_invalidation_);
105  pending_invalidation_.Clear();
106
107  gfx::Rect visible_layer_rect = gfx::ScaleToEnclosingRect(
108      visible_content_rect(), 1.f / contents_scale_x());
109  if (layer_tree_host()->settings().using_synchronous_renderer_compositor) {
110    // Workaround for http://crbug.com/235910 - to retain backwards compat
111    // the full page content must always be provided in the picture layer.
112    visible_layer_rect = gfx::Rect(bounds());
113  }
114  DCHECK(client_);
115  updated |= pile_->Update(client_,
116                           SafeOpaqueBackgroundColor(),
117                           contents_opaque(),
118                           client_->FillsBoundsCompletely(),
119                           pile_invalidation_,
120                           visible_layer_rect,
121                           update_source_frame_number_,
122                           rendering_stats_instrumentation());
123  last_updated_visible_content_rect_ = visible_content_rect();
124
125  if (updated) {
126    SetNeedsPushProperties();
127  } else {
128    // If this invalidation did not affect the pile, then it can be cleared as
129    // an optimization.
130    pile_invalidation_.Clear();
131  }
132
133  return updated;
134}
135
136void PictureLayer::SetIsMask(bool is_mask) {
137  is_mask_ = is_mask;
138}
139
140void PictureLayer::SetHasGpuRasterizationHint(bool has_hint) {
141  switch (has_gpu_rasterization_hint_) {
142    case TRIBOOL_UNKNOWN:  // Fall-through.
143    case TRIBOOL_TRUE:
144      has_gpu_rasterization_hint_ = has_hint ? TRIBOOL_TRUE : TRIBOOL_FALSE;
145      break;
146    case TRIBOOL_FALSE:
147      // GPU rasterization cannot be enabled once disabled.
148      // This is done to prevent frequent invalidations and visual flashing.
149      break;
150    default:
151      NOTREACHED();
152  }
153  // No need to set needs commit or push-properties.
154  // If only the hint changes and the layer is still valid, there is no need
155  // to invalidate the rasterization for the whole layer. If there is an
156  // invalidation (current or future) we will re-raster everything so that it
157  // is consistent across the layer.
158}
159
160bool PictureLayer::ShouldUseGpuRasterization() const {
161  switch (layer_tree_host()->settings().rasterization_site) {
162    case LayerTreeSettings::CpuRasterization:
163      return false;
164    case LayerTreeSettings::HybridRasterization:
165      return has_gpu_rasterization_hint_ == TRIBOOL_TRUE &&
166             pile_->is_suitable_for_gpu_rasterization();
167    case LayerTreeSettings::GpuRasterization:
168      return true;
169  }
170  NOTREACHED();
171  return false;
172}
173
174bool PictureLayer::SupportsLCDText() const {
175  return true;
176}
177
178skia::RefPtr<SkPicture> PictureLayer::GetPicture() const {
179  // We could either flatten the PicturePile into a single SkPicture,
180  // or paint a fresh one depending on what we intend to do with the
181  // picture. For now we just paint a fresh one to get consistent results.
182  if (!DrawsContent())
183    return skia::RefPtr<SkPicture>();
184
185  int width = bounds().width();
186  int height = bounds().height();
187  gfx::RectF opaque;
188
189  skia::RefPtr<SkPicture> picture = skia::AdoptRef(new SkPicture);
190  SkCanvas* canvas = picture->beginRecording(width, height);
191  client_->PaintContents(canvas, gfx::Rect(width, height), &opaque);
192  picture->endRecording();
193  return picture;
194}
195
196void PictureLayer::RunMicroBenchmark(MicroBenchmark* benchmark) {
197  benchmark->RunOnLayer(this);
198}
199
200}  // namespace cc
201