cc: Clean up RecordingSource API

cc/layers/picture_layer.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/layers/picture_layer.h"
 
 #include "base/auto_reset.h"
 #include "base/trace_event/trace_event.h"
 #include "cc/layers/content_layer_client.h"
 #include "cc/layers/picture_layer_impl.h"
@@ skipping 13 matching lines @@
 }
 
 PictureLayer::PictureLayer(ContentLayerClient* client)
     : instrumentation_object_tracker_(id()),
       update_source_frame_number_(-1),
       is_mask_(false) {
   inputs_.client = client;
 }
 
 PictureLayer::PictureLayer(ContentLayerClient* client,
-                           std::unique_ptr<RecordingSource> source)
+                           const PictureLayerData& pl_data,
+                           const ContentLayerClientData& clc_data)
     : PictureLayer(client) {
-  recording_source_ = std::move(source);
+  pl_data_ = pl_data;

[vmpstr, 2016/07/19 23:43:22]

set these in the initialization list just above

[Menglin, 2016/07/20 00:28:42]

Done.

[Menglin, 2016/07/20 21:25:22]

Actually, if i move the initialization in the list, it'll have this compile
error "an initializer for a delegating constructor must appear alone", because i
guess when I delegate the member initialization to another constructor, there is
an assumption that the other constructor initializes the object completely,
including all members. I can't therefore initialize any of the members again.

+  clc_data_ = clc_data;
 }
 
 PictureLayer::~PictureLayer() {
 }
 
 std::unique_ptr<LayerImpl> PictureLayer::CreateLayerImpl(
     LayerTreeImpl* tree_impl) {
   return PictureLayerImpl::Create(tree_impl, id(), is_mask_);
 }
 
 void PictureLayer::PushPropertiesTo(LayerImpl* base_layer) {
   Layer::PushPropertiesTo(base_layer);
   TRACE_EVENT0("cc", "PictureLayer::PushPropertiesTo");
   PictureLayerImpl* layer_impl = static_cast<PictureLayerImpl*>(base_layer);
   // TODO(danakj): Make is_mask_ a constructor parameter for PictureLayer.
   DCHECK_EQ(layer_impl->is_mask(), is_mask_);
   DropRecordingSourceContentIfInvalid();
 
   layer_impl->SetNearestNeighbor(inputs_.nearest_neighbor);
 
   // Preserve lcd text settings from the current raster source.
   bool can_use_lcd_text = layer_impl->RasterSourceUsesLCDText();
+  std::unique_ptr<RecordingSource> recording_source(

[vmpstr, 2016/07/19 23:43:22]

Just create this on the stack if you need it. Do you need it? Can we have a
CreateRasterSource function that bypasses a recording source? Or is there some
non trivial work that happens there?

[Menglin, 2016/07/20 00:18:13]

Currently the raster source is constructed based on a recording source.
RasterSource(const RecordingSource* other, bool can_use_lcd_text). I can add
something like RasterSource(const PictureLayer* other, bool can_use_lcd_text) so
that it can be created from a PictureLayer, bypassing a recording source, and we
don't need the recording source at all. It's not too much work to do that

[vmpstr, 2016/07/20 00:27:06]

I think we can just have RasterSource(display_list, background_color,
requires_clear, is_solid_color, ...) and whatever else we need. All the raster
source's current ctor is doing is unpacking the recording source into those
variables. We might as well just pass the variables. 

[Menglin, 2016/07/20 21:25:22]

I change it to RasterSource(const PictureLayerData& layer_data,
               const ContentLayerClientData& client_data,
               bool can_use_lcd_text);
because putting each single member as an argument makes the function declaration
look very bulky..

+      new RecordingSource(pl_data_, clc_data_));
   scoped_refptr<RasterSource> raster_source =
-      recording_source_->CreateRasterSource(can_use_lcd_text);
+      recording_source->CreateRasterSource(can_use_lcd_text);
   layer_impl->set_gpu_raster_max_texture_size(
       layer_tree_host()->device_viewport_size());
   layer_impl->UpdateRasterSource(raster_source, &last_updated_invalidation_,
                                  nullptr);
   DCHECK(last_updated_invalidation_.IsEmpty());
 }
 
 void PictureLayer::SetLayerTreeHost(LayerTreeHost* host) {
   Layer::SetLayerTreeHost(host);
   if (!host)
     return;
 
-  if (!recording_source_)
-    recording_source_.reset(new RecordingSource);
-  recording_source_->SetSlowdownRasterScaleFactor(
+  pl_data_.reset();

[vmpstr, 2016/07/19 23:43:22]

Where is PictureLayerData defined? I can't find it anywhere. 

From the uses around here, it doesn't appear to be a pointer, so it shouldn't
have a lower case reset function. Maybe just pl_data_ = PictureLayerData();? if
you need to clear it?

[Menglin, 2016/07/20 00:18:13]

Now it's in recording_source.h. I had it there because the RecordingSource
constructor needs to know those types. If we remove the whole recording source,
it'll be moved in picture_layer.h
It's a struct. and yeah i can just use the constructor to clear it. Thanks for
letting me know the code style

+  clc_data_.reset();
+  SetSlowdownRasterScaleFactor(
       host->debug_state().slow_down_raster_scale_factor);
   // If we need to enable image decode tasks, then we have to generate the
   // discardable images metadata.
   const LayerTreeSettings& settings = layer_tree_host()->settings();
-  recording_source_->SetGenerateDiscardableImagesMetadata(
-      settings.image_decode_tasks_enabled);
+  SetGenerateDiscardableImagesMetadata(settings.image_decode_tasks_enabled);
 }
 
 void PictureLayer::SetNeedsDisplayRect(const gfx::Rect& layer_rect) {
   DCHECK(!layer_tree_host() || !layer_tree_host()->in_paint_layer_contents());
-  if (recording_source_)
-    recording_source_->SetNeedsDisplayRect(layer_rect);
+  SetNeedsDisplayRectSimple(layer_rect);
   Layer::SetNeedsDisplayRect(layer_rect);
 }
 
 bool PictureLayer::Update() {
   update_source_frame_number_ = layer_tree_host()->source_frame_number();
   bool updated = Layer::Update();
 
   gfx::Size layer_size = paint_properties().bounds;
 
-  recording_source_->SetBackgroundColor(SafeOpaqueBackgroundColor());
-  recording_source_->SetRequiresClear(!contents_opaque() &&
-                                      !inputs_.client->FillsBoundsCompletely());
+  SetBackgroundColorSimple(SafeOpaqueBackgroundColor());
+  SetRequiresClear(!contents_opaque() &&
+                   !inputs_.client->FillsBoundsCompletely());
 
   TRACE_EVENT1("cc", "PictureLayer::Update",
                "source_frame_number",
                layer_tree_host()->source_frame_number());
   devtools_instrumentation::ScopedLayerTreeTask update_layer(
       devtools_instrumentation::kUpdateLayer, id(), layer_tree_host()->id());
 
   // UpdateAndExpandInvalidation will give us an invalidation that covers
   // anything not explicitly recorded in this frame. We give this region
   // to the impl side so that it drops tiles that may not have a recording
   // for them.
   DCHECK(inputs_.client);
-  updated |= recording_source_->UpdateAndExpandInvalidation(
-      inputs_.client, &last_updated_invalidation_, layer_size,
-      update_source_frame_number_, RecordingSource::RECORD_NORMALLY);
+  updated |= UpdateAndExpandInvalidation(
+      &last_updated_invalidation_, layer_size, RecordingSource::RECORD_NORMALLY,
+      &pl_data_, &clc_data_, &invalidation_);
 
   if (updated) {
     SetNeedsPushProperties();
   } else {
     // If this invalidation did not affect the recording source, then it can be
     // cleared as an optimization.
     last_updated_invalidation_.Clear();
   }
 
   return updated;
 }
 
 void PictureLayer::SetIsMask(bool is_mask) {
   is_mask_ = is_mask;
 }
 
 sk_sp<SkPicture> PictureLayer::GetPicture() const {
   // We could either flatten the RecordingSource into a single
   // SkPicture, or paint a fresh one depending on what we intend to do with the
   // picture. For now we just paint a fresh one to get consistent results.
   if (!DrawsContent())
     return nullptr;
 
   gfx::Size layer_size = bounds();
-  std::unique_ptr<RecordingSource> recording_source(new RecordingSource);
   Region recording_invalidation;
-  recording_source->UpdateAndExpandInvalidation(
-      inputs_.client, &recording_invalidation, layer_size,
-      update_source_frame_number_, RecordingSource::RECORD_NORMALLY);
-
+  InvalidationRegion invalidation_local;

[vmpstr, 2016/07/19 23:43:22]

I don't think you need the word "local".. lack of training underscore implies
that it's local. 

[Menglin, 2016/07/20 21:25:22]

Done.

+  PictureLayerData pl_data_local = PictureLayerData();
+  ContentLayerClientData clc_data_local = ContentLayerClientData();
+  UpdateAndExpandInvalidation(&recording_invalidation, layer_size,
+                              RecordingSource::RECORD_NORMALLY, &pl_data_local,
+                              &clc_data_local, &invalidation_local);
+  std::unique_ptr<RecordingSource> recording_source(

[vmpstr, 2016/07/19 23:43:22]

Same comment as above: Either create it on the stack or just don't create it :)

[Menglin, 2016/07/20 21:25:22]

Done.

+      new RecordingSource(pl_data_local, clc_data_local));
   scoped_refptr<RasterSource> raster_source =
       recording_source->CreateRasterSource(false);
 
   return raster_source->GetFlattenedPicture();
 }
 
 bool PictureLayer::IsSuitableForGpuRasterization() const {
-  return recording_source_->IsSuitableForGpuRasterization();
+  // The display list needs to be created (see: UpdateAndExpandInvalidation)
+  // before checking for suitability. There are cases where an update will not
+  // create a display list (e.g., if the size is empty). We return true in these
+  // cases because the gpu suitability bit sticks false.
+  return !clc_data_.display_list ||
+         clc_data_.display_list->IsSuitableForGpuRasterization();
 }
 
 void PictureLayer::ClearClient() {
   inputs_.client = nullptr;
   UpdateDrawsContent(HasDrawableContent());
 }
 
 void PictureLayer::SetNearestNeighbor(bool nearest_neighbor) {
   if (inputs_.nearest_neighbor == nearest_neighbor)
     return;
 
   inputs_.nearest_neighbor = nearest_neighbor;
   SetNeedsCommit();
 }
 
 bool PictureLayer::HasDrawableContent() const {
   return inputs_.client && Layer::HasDrawableContent();
 }
 
 void PictureLayer::SetTypeForProtoSerialization(proto::LayerNode* proto) const {
   proto->set_type(proto::LayerNode::PICTURE_LAYER);
 }
 
 void PictureLayer::LayerSpecificPropertiesToProto(
     proto::LayerProperties* proto) {
   Layer::LayerSpecificPropertiesToProto(proto);
   DropRecordingSourceContentIfInvalid();
 
   proto::PictureLayerProperties* picture = proto->mutable_picture();
-  recording_source_->ToProtobuf(picture->mutable_recording_source());
+
+  RectToProto(clc_data_.recorded_viewport,
+              picture->mutable_recorded_viewport());
+  SizeToProto(pl_data_.size, picture->mutable_size());
+  picture->set_slow_down_raster_scale_factor_for_debug(
+      pl_data_.slow_down_raster_scale_factor_for_debug);
+  picture->set_generate_discardable_images_metadata(
+      pl_data_.generate_discardable_images_metadata);
+  picture->set_requires_clear(pl_data_.requires_clear);
+  picture->set_is_solid_color(pl_data_.is_solid_color);
+  picture->set_clear_canvas_with_debug_color(
+      pl_data_.clear_canvas_with_debug_color);
+  picture->set_solid_color(static_cast<uint64_t>(pl_data_.solid_color));
+  picture->set_background_color(
+      static_cast<uint64_t>(pl_data_.background_color));
+  if (clc_data_.display_list)
+    clc_data_.display_list->ToProtobuf(picture->mutable_display_list());
 
   // Add all SkPicture items to the picture cache.
-  const DisplayItemList* display_list = recording_source_->GetDisplayItemList();
+  const DisplayItemList* display_list = GetDisplayItemList();
   if (display_list) {
     for (auto it = display_list->begin(); it != display_list->end(); ++it) {
       sk_sp<const SkPicture> picture = it->GetPicture();
       // Only DrawingDisplayItems have SkPictures.
       if (!picture)
         continue;
 
       layer_tree_host()->engine_picture_cache()->MarkUsed(picture.get());
     }
   }
 
   RegionToProto(last_updated_invalidation_, picture->mutable_invalidation());
   picture->set_is_mask(is_mask_);
   picture->set_nearest_neighbor(inputs_.nearest_neighbor);
 
   picture->set_update_source_frame_number(update_source_frame_number_);
 
   last_updated_invalidation_.Clear();
 }
 
 void PictureLayer::FromLayerSpecificPropertiesProto(
     const proto::LayerProperties& proto) {
   Layer::FromLayerSpecificPropertiesProto(proto);
   const proto::PictureLayerProperties& picture = proto.picture();
   // If this is a new layer, ensure it has a recording source. During layer
   // hierarchy deserialization, ::SetLayerTreeHost(...) is not called, but
   // instead the member is set directly, so it needs to be set here explicitly.
-  if (!recording_source_)
-    recording_source_.reset(new RecordingSource);
+  pl_data_.reset();
+  clc_data_.reset();
+  std::vector<uint32_t> used_engine_picture_ids;
 
-  std::vector<uint32_t> used_engine_picture_ids;
-  recording_source_->FromProtobuf(picture.recording_source(),
-                                  layer_tree_host()->client_picture_cache(),
-                                  &used_engine_picture_ids);
+  DCHECK(layer_tree_host()->client_picture_cache());
+  clc_data_.recorded_viewport = ProtoToRect(picture.recorded_viewport());
+  pl_data_.size = ProtoToSize(picture.size());
+  pl_data_.slow_down_raster_scale_factor_for_debug =
+      picture.slow_down_raster_scale_factor_for_debug();
+  pl_data_.generate_discardable_images_metadata =
+      picture.generate_discardable_images_metadata();
+  pl_data_.requires_clear = picture.requires_clear();
+  pl_data_.is_solid_color = picture.is_solid_color();
+  pl_data_.clear_canvas_with_debug_color =
+      picture.clear_canvas_with_debug_color();
+  pl_data_.solid_color = static_cast<SkColor>(picture.solid_color());
+  pl_data_.background_color = static_cast<SkColor>(picture.background_color());
+
+  // This might not exist if the |clc_data_.display_list| of the serialized
+  // RecordingSource was null, which can happen if |Clear()| is
+  // called.
+  if (picture.has_display_list()) {
+    clc_data_.display_list = DisplayItemList::CreateFromProto(
+        picture.display_list(), layer_tree_host()->client_picture_cache(),
+        &used_engine_picture_ids);
+    FinishDisplayItemListUpdate(&pl_data_, &clc_data_);
+  } else {
+    clc_data_.display_list = nullptr;
+  }
 
   // Inform picture cache about which SkPictures are now in use.
   for (uint32_t engine_picture_id : used_engine_picture_ids)
     layer_tree_host()->client_picture_cache()->MarkUsed(engine_picture_id);
 
   Region new_invalidation = RegionFromProto(picture.invalidation());
   last_updated_invalidation_.Swap(&new_invalidation);
   is_mask_ = picture.is_mask();
   inputs_.nearest_neighbor = picture.nearest_neighbor();
 
   update_source_frame_number_ = picture.update_source_frame_number();
 }
 
 void PictureLayer::RunMicroBenchmark(MicroBenchmark* benchmark) {
   benchmark->RunOnLayer(this);
 }
 
+bool PictureLayer::UpdateAndExpandInvalidation(
+    Region* invalidation,
+    const gfx::Size& layer_size,
+    RecordingSource::RecordingMode recording_mode,
+    PictureLayerData* pl_data,
+    ContentLayerClientData* clc_data,
+    InvalidationRegion* invalidation_state) const {
+  bool updated = false;
+
+  if (pl_data->size != layer_size)
+    pl_data->size = layer_size;
+
+  invalidation_state->Swap(invalidation);
+  invalidation_state->Clear();
+
+  gfx::Rect new_recorded_viewport = inputs_.client->PaintableRegion();
+  if (new_recorded_viewport != clc_data->recorded_viewport) {
+    UpdateInvalidationForNewViewport(clc_data->recorded_viewport,
+                                     new_recorded_viewport, invalidation);
+    clc_data->recorded_viewport = new_recorded_viewport;
+    updated = true;
+  }
+
+  if (!updated && !invalidation->Intersects(clc_data->recorded_viewport))
+    return false;
+
+  if (invalidation->IsEmpty())
+    return false;
+
+  ContentLayerClient::PaintingControlSetting painting_control =
+      ContentLayerClient::PAINTING_BEHAVIOR_NORMAL;
+
+  switch (recording_mode) {
+    case RecordingSource::RECORD_NORMALLY:
+      // Already setup for normal recording.
+      break;
+    case RecordingSource::RECORD_WITH_PAINTING_DISABLED:
+      painting_control = ContentLayerClient::DISPLAY_LIST_PAINTING_DISABLED;
+      break;
+    case RecordingSource::RECORD_WITH_CACHING_DISABLED:
+      painting_control = ContentLayerClient::DISPLAY_LIST_CACHING_DISABLED;
+      break;
+    case RecordingSource::RECORD_WITH_CONSTRUCTION_DISABLED:
+      painting_control = ContentLayerClient::DISPLAY_LIST_CONSTRUCTION_DISABLED;
+      break;
+    case RecordingSource::RECORD_WITH_SUBSEQUENCE_CACHING_DISABLED:
+      painting_control = ContentLayerClient::SUBSEQUENCE_CACHING_DISABLED;
+      break;
+    case RecordingSource::RECORD_WITH_SK_NULL_CANVAS:
+    case RecordingSource::RECORDING_MODE_COUNT:
+      NOTREACHED();
+  }
+
+  // TODO(vmpstr): Add a slow_down_recording_scale_factor_for_debug_ to be able
+  // to slow down recording.
+  clc_data->display_list =
+      inputs_.client->PaintContentsToDisplayList(painting_control);
+  clc_data->painter_reported_memory_usage =
+      inputs_.client->GetApproximateUnsharedMemoryUsage();
+
+  FinishDisplayItemListUpdate(pl_data, clc_data);
+
+  return true;
+}
+
+void PictureLayer::SetEmptyBounds() {
+  pl_data_.size = gfx::Size();
+  Clear();
+}
+
+void PictureLayer::SetSlowdownRasterScaleFactor(int factor) {

[vmpstr, 2016/07/19 23:43:22]

As far as I can tell there's not a lot of places that call these setters. Can we
just set the variable directly without introducing these functions?

[Menglin, 2016/07/20 00:18:13]

OK. I will check each one of them, and do the clean up.

[Menglin, 2016/07/20 21:25:22]

For now I only removed SetSlowdownRasterScaleFactor, because the others are used
in the test code. I'll deal with the rest when I change the test code in the
next patch

+  pl_data_.slow_down_raster_scale_factor_for_debug = factor;
+}
+
+void PictureLayer::SetGenerateDiscardableImagesMetadata(
+    bool generate_metadata) {
+  pl_data_.generate_discardable_images_metadata = generate_metadata;
+}
+
+void PictureLayer::SetBackgroundColorSimple(SkColor background_color) {
+  pl_data_.background_color = background_color;
+}
+
+void PictureLayer::SetRequiresClear(bool requires_clear) {
+  pl_data_.requires_clear = requires_clear;
+}
+
+void PictureLayer::SetNeedsDisplayRectSimple(const gfx::Rect& layer_rect) {
+  if (!layer_rect.IsEmpty()) {
+    // Clamp invalidation to the layer bounds.
+    invalidation_.Union(
+        gfx::IntersectRects(layer_rect, gfx::Rect(pl_data_.size)));
+  }
+}
+
+gfx::Size PictureLayer::GetSize() const {
+  return pl_data_.size;
+}
+
+const DisplayItemList* PictureLayer::GetDisplayItemList() {
+  return clc_data_.display_list.get();
+}
+
+void PictureLayer::Clear() {
+  clc_data_.recorded_viewport = gfx::Rect();
+  clc_data_.display_list = nullptr;
+  clc_data_.painter_reported_memory_usage = 0;
+  pl_data_.is_solid_color = false;
+}
+
 void PictureLayer::DropRecordingSourceContentIfInvalid() {
   int source_frame_number = layer_tree_host()->source_frame_number();
-  gfx::Size recording_source_bounds = recording_source_->GetSize();
+  gfx::Size recording_source_bounds = GetSize();
 
   gfx::Size layer_bounds = bounds();
   if (paint_properties().source_frame_number == source_frame_number)
     layer_bounds = paint_properties().bounds;
 
   // If update called, then recording source size must match bounds pushed to
   // impl layer.
   DCHECK(update_source_frame_number_ != source_frame_number ||
          layer_bounds == recording_source_bounds)
       << " bounds " << layer_bounds.ToString() << " recording source "
       << recording_source_bounds.ToString();
 
   if (update_source_frame_number_ != source_frame_number &&
       recording_source_bounds != layer_bounds) {
     // Update may not get called for the layer (if it's not in the viewport
     // for example), even though it has resized making the recording source no
     // longer valid. In this case just destroy the recording source.
-    recording_source_->SetEmptyBounds();
+    SetEmptyBounds();
   }
 }
 
+void PictureLayer::FinishDisplayItemListUpdate(
+    PictureLayerData* pl_data,
+    ContentLayerClientData* clc_data) const {
+  TRACE_EVENT0("cc", "PictureLayer::FinishDisplayItemListUpdate");
+  DetermineIfSolidColor(pl_data, clc_data);
+  clc_data->display_list->EmitTraceSnapshot();
+  if (pl_data->generate_discardable_images_metadata)
+    clc_data->display_list->GenerateDiscardableImagesMetadata();
+}
+
+void PictureLayer::DetermineIfSolidColor(
+    PictureLayerData* pl_data,
+    ContentLayerClientData* clc_data) const {
+  DCHECK(clc_data->display_list);
+  pl_data->is_solid_color = false;
+  pl_data->solid_color = SK_ColorTRANSPARENT;
+
+  if (!clc_data->display_list->ShouldBeAnalyzedForSolidColor())
+    return;
+
+  TRACE_EVENT1("cc", "PictureLayer::DetermineIfSolidColor", "opcount",
+               clc_data->display_list->ApproximateOpCount());
+  gfx::Size layer_size = pl_data->size;
+  skia::AnalysisCanvas canvas(layer_size.width(), layer_size.height());
+  clc_data->display_list->Raster(&canvas, nullptr, gfx::Rect(), 1.f);
+  pl_data->is_solid_color = canvas.GetColorIfSolid(&pl_data->solid_color);
+}
+
+void PictureLayer::UpdateInvalidationForNewViewport(
+    const gfx::Rect& old_recorded_viewport,
+    const gfx::Rect& new_recorded_viewport,
+    Region* invalidation) const {
+  // Invalidate newly-exposed and no-longer-exposed areas.
+  Region newly_exposed_region(new_recorded_viewport);
+  newly_exposed_region.Subtract(old_recorded_viewport);
+  invalidation->Union(newly_exposed_region);
+
+  Region no_longer_exposed_region(old_recorded_viewport);
+  no_longer_exposed_region.Subtract(new_recorded_viewport);
+  invalidation->Union(no_longer_exposed_region);
+}
+
 }  // namespace cc