cc/playback/display_list_recording_source.cc

   1 // Copyright 2014 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/playback/display_list_recording_source.h"
   6
   7 #include <algorithm>
   8
   9 #include "cc/base/histograms.h"
  10 #include "cc/base/region.h"
  11 #include "cc/layers/content_layer_client.h"
  12 #include "cc/playback/display_item_list.h"
  13 #include "cc/playback/display_list_raster_source.h"
  14 #include "skia/ext/analysis_canvas.h"
  15
  16 namespace {
  17
  18 // Layout pixel buffer around the visible layer rect to record.  Any base
  19 // picture that intersects the visible layer rect expanded by this distance
  20 // will be recorded.
  21 const int kPixelDistanceToRecord = 4000;
  22
  23 // This is the distance, in layer space, by which the recorded viewport has to
  24 // change before causing a paint of the new content. For example, it means
  25 // that one has to scroll a very large page by 512 pixels before we will
  26 // re-record a new DisplayItemList for an updated recorded viewport.
  27 const int kMinimumDistanceBeforeUpdatingRecordedViewport = 512;
  28
  29 #ifdef NDEBUG
  30 const bool kDefaultClearCanvasSetting = false;
  31 #else
  32 const bool kDefaultClearCanvasSetting = true;
  33 #endif
  34
  35 DEFINE_SCOPED_UMA_HISTOGRAM_AREA_TIMER(
  36     ScopedDisplayListRecordingSourceUpdateTimer,
  37     "Compositing.%s.DisplayListRecordingSource.UpdateUs",
  38     "Compositing.%s.DisplayListRecordingSource.UpdateInvalidatedAreaPerMs");
  39
  40 }  // namespace
  41
  42 namespace cc {
  43
  44 DisplayListRecordingSource::DisplayListRecordingSource(
  45     const gfx::Size& grid_cell_size)
  46     : slow_down_raster_scale_factor_for_debug_(0),
  47       gather_pixel_refs_(false),
  48       requires_clear_(false),
  49       is_solid_color_(false),
  50       clear_canvas_with_debug_color_(kDefaultClearCanvasSetting),
  51       solid_color_(SK_ColorTRANSPARENT),
  52       background_color_(SK_ColorTRANSPARENT),
  53       pixel_record_distance_(kPixelDistanceToRecord),
  54       grid_cell_size_(grid_cell_size),
  55       painter_reported_memory_usage_(0),
  56       is_suitable_for_gpu_rasterization_(true) {}
  57
  58 DisplayListRecordingSource::~DisplayListRecordingSource() {
  59 }
  60
  61 // This method only really makes sense to call if the size of the layer didn't
  62 // change.
  63 bool DisplayListRecordingSource::ExposesEnoughNewArea(
  64     const gfx::Rect& current_recorded_viewport,
  65     const gfx::Rect& potential_new_recorded_viewport,
  66     const gfx::Size& layer_size) {
  67   // If both are empty, nothing to do.
  68   if (current_recorded_viewport.IsEmpty() &&
  69       potential_new_recorded_viewport.IsEmpty())
  70     return false;
  71
  72   // Re-record when going from empty to not-empty, to cover cases where
  73   // the layer is recorded for the first time, or otherwise becomes visible.
  74   if (current_recorded_viewport.IsEmpty())
  75     return true;
  76
  77   // Re-record if the new viewport includes area outside of a skirt around the
  78   // existing viewport.
  79   gfx::Rect expanded_viewport(current_recorded_viewport);
  80   expanded_viewport.Inset(-kMinimumDistanceBeforeUpdatingRecordedViewport,
  81                           -kMinimumDistanceBeforeUpdatingRecordedViewport);
  82   if (!expanded_viewport.Contains(potential_new_recorded_viewport))
  83     return true;
  84
  85   // Even if the new viewport doesn't include enough new area to satisfy the
  86   // condition above, re-record anyway if touches a layer edge not touched by
  87   // the existing viewport. Viewports are clipped to layer boundaries, so if the
  88   // new viewport touches a layer edge not touched by the existing viewport,
  89   // the new viewport must expose new area that touches this layer edge. Since
  90   // this new area touches a layer edge, it's impossible to expose more area in
  91   // that direction, so recording cannot be deferred until the exposed new area
  92   // satisfies the condition above.
  93   if (potential_new_recorded_viewport.x() == 0 &&
  94       current_recorded_viewport.x() != 0)
  95     return true;
  96   if (potential_new_recorded_viewport.y() == 0 &&
  97       current_recorded_viewport.y() != 0)
  98     return true;
  99   if (potential_new_recorded_viewport.right() == layer_size.width() &&
 100       current_recorded_viewport.right() != layer_size.width())
 101     return true;
 102   if (potential_new_recorded_viewport.bottom() == layer_size.height() &&
 103       current_recorded_viewport.bottom() != layer_size.height())
 104     return true;
 105
 106   return false;
 107 }
 108
 109 bool DisplayListRecordingSource::UpdateAndExpandInvalidation(
 110     ContentLayerClient* painter,
 111     Region* invalidation,
 112     const gfx::Size& layer_size,
 113     const gfx::Rect& visible_layer_rect,
 114     int frame_number,
 115     RecordingMode recording_mode) {
 116   ScopedDisplayListRecordingSourceUpdateTimer timer;
 117   bool updated = false;
 118
 119   if (size_ != layer_size) {
 120     size_ = layer_size;
 121     updated = true;
 122   }
 123
 124   // The recorded viewport is the visible layer rect, expanded
 125   // by the pixel record distance, up to a maximum of the total
 126   // layer size.
 127   gfx::Rect potential_new_recorded_viewport = visible_layer_rect;
 128   potential_new_recorded_viewport.Inset(-pixel_record_distance_,
 129                                         -pixel_record_distance_);
 130   potential_new_recorded_viewport.Intersect(gfx::Rect(GetSize()));
 131
 132   if (updated ||
 133       ExposesEnoughNewArea(recorded_viewport_, potential_new_recorded_viewport,
 134                            GetSize())) {
 135     gfx::Rect old_recorded_viewport = recorded_viewport_;
 136     recorded_viewport_ = potential_new_recorded_viewport;
 137
 138     // Invalidate newly-exposed and no-longer-exposed areas.
 139     Region newly_exposed_region(recorded_viewport_);
 140     newly_exposed_region.Subtract(old_recorded_viewport);
 141     invalidation->Union(newly_exposed_region);
 142
 143     Region no_longer_exposed_region(old_recorded_viewport);
 144     no_longer_exposed_region.Subtract(recorded_viewport_);
 145     invalidation->Union(no_longer_exposed_region);
 146
 147     updated = true;
 148   }
 149
 150   // Count the area that is being invalidated.
 151   Region recorded_invalidation(*invalidation);
 152   recorded_invalidation.Intersect(recorded_viewport_);
 153   for (Region::Iterator it(recorded_invalidation); it.has_rect(); it.next())
 154     timer.AddArea(it.rect().size().GetArea());
 155
 156   if (!updated && !invalidation->Intersects(recorded_viewport_))
 157     return false;
 158
 159   ContentLayerClient::PaintingControlSetting painting_control =
 160       ContentLayerClient::PAINTING_BEHAVIOR_NORMAL;
 161
 162   switch (recording_mode) {
 163     case RECORD_NORMALLY:
 164       // Already setup for normal recording.
 165       break;
 166     case RECORD_WITH_PAINTING_DISABLED:
 167       painting_control = ContentLayerClient::DISPLAY_LIST_PAINTING_DISABLED;
 168       break;
 169     case RECORD_WITH_CACHING_DISABLED:
 170       painting_control = ContentLayerClient::DISPLAY_LIST_CACHING_DISABLED;
 171       break;
 172     case RECORD_WITH_CONSTRUCTION_DISABLED:
 173       painting_control = ContentLayerClient::DISPLAY_LIST_CONSTRUCTION_DISABLED;
 174       break;
 175     default:
 176       // case RecordingSource::RECORD_WITH_SK_NULL_CANVAS should not be reached
 177       NOTREACHED();
 178   }
 179
 180   // TODO(vmpstr): Add a slow_down_recording_scale_factor_for_debug_ to be able
 181   // to slow down recording.
 182   display_list_ =
 183       painter->PaintContentsToDisplayList(recorded_viewport_, painting_control);
 184   painter_reported_memory_usage_ = painter->GetApproximateUnsharedMemoryUsage();
 185
 186   is_suitable_for_gpu_rasterization_ =
 187       display_list_->IsSuitableForGpuRasterization();
 188   DetermineIfSolidColor();
 189   display_list_->EmitTraceSnapshot();
 190   if (gather_pixel_refs_)
 191     display_list_->GatherPixelRefs(grid_cell_size_);
 192
 193   return true;
 194 }
 195
 196 gfx::Size DisplayListRecordingSource::GetSize() const {
 197   return size_;
 198 }
 199
 200 void DisplayListRecordingSource::SetEmptyBounds() {
 201   size_ = gfx::Size();
 202   Clear();
 203 }
 204
 205 void DisplayListRecordingSource::SetSlowdownRasterScaleFactor(int factor) {
 206   slow_down_raster_scale_factor_for_debug_ = factor;
 207 }
 208
 209 void DisplayListRecordingSource::SetGatherPixelRefs(bool gather_pixel_refs) {
 210   gather_pixel_refs_ = gather_pixel_refs;
 211 }
 212
 213 void DisplayListRecordingSource::SetBackgroundColor(SkColor background_color) {
 214   background_color_ = background_color;
 215 }
 216
 217 void DisplayListRecordingSource::SetRequiresClear(bool requires_clear) {
 218   requires_clear_ = requires_clear;
 219 }
 220
 221 void DisplayListRecordingSource::SetUnsuitableForGpuRasterizationForTesting() {
 222   is_suitable_for_gpu_rasterization_ = false;
 223 }
 224
 225 bool DisplayListRecordingSource::IsSuitableForGpuRasterization() const {
 226   return is_suitable_for_gpu_rasterization_;
 227 }
 228
 229 scoped_refptr<RasterSource> DisplayListRecordingSource::CreateRasterSource(
 230     bool can_use_lcd_text) const {
 231   return scoped_refptr<RasterSource>(
 232       DisplayListRasterSource::CreateFromDisplayListRecordingSource(
 233           this, can_use_lcd_text));
 234 }
 235
 236 gfx::Size DisplayListRecordingSource::GetTileGridSizeForTesting() const {
 237   return gfx::Size();
 238 }
 239
 240 void DisplayListRecordingSource::DetermineIfSolidColor() {
 241   DCHECK(display_list_.get());
 242   is_solid_color_ = false;
 243   solid_color_ = SK_ColorTRANSPARENT;
 244
 245   if (!display_list_->ShouldBeAnalyzedForSolidColor())
 246     return;
 247
 248   gfx::Size layer_size = GetSize();
 249   skia::AnalysisCanvas canvas(layer_size.width(), layer_size.height());
 250   display_list_->Raster(&canvas, nullptr, gfx::Rect(), 1.f);
 251   is_solid_color_ = canvas.GetColorIfSolid(&solid_color_);
 252 }
 253
 254 void DisplayListRecordingSource::Clear() {
 255   recorded_viewport_ = gfx::Rect();
 256   display_list_ = NULL;
 257   painter_reported_memory_usage_ = 0;
 258   is_solid_color_ = false;
 259 }
 260
 261 }  // namespace cc