cc: Change required_for_activation bookkeeping.

cc/layers/picture_layer_impl.h

 // 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.
 
 #ifndef CC_LAYERS_PICTURE_LAYER_IMPL_H_
 #define CC_LAYERS_PICTURE_LAYER_IMPL_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 74 matching lines @@
   virtual ~PictureLayerImpl();
 
   // LayerImpl overrides.
   virtual const char* LayerTypeAsString() const OVERRIDE;
   virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl)
       OVERRIDE;
   virtual void PushPropertiesTo(LayerImpl* layer) OVERRIDE;
   virtual void AppendQuads(QuadSink* quad_sink,
                            AppendQuadsData* append_quads_data) OVERRIDE;
   virtual void UpdateTilePriorities() OVERRIDE;
+  virtual void NotifyTileInitialized(const Tile* tile) OVERRIDE;
   virtual void DidBecomeActive() OVERRIDE;
   virtual void DidBeginTracing() OVERRIDE;
   virtual void ReleaseResources() OVERRIDE;
   virtual void CalculateContentsScale(float ideal_contents_scale,
                                       float device_scale_factor,
                                       float page_scale_factor,
                                       float maximum_animation_contents_scale,
                                       bool animating_transform_to_screen,
                                       float* contents_scale_x,
                                       float* contents_scale_y,
@@ skipping 27 matching lines @@
 
   void SetUseGpuRasterization(bool use_gpu);
   bool ShouldUseGpuRasterization() const { return use_gpu_rasterization_; }
 
   // Functions used by tile manager.
   void DidUnregisterLayer();
   PictureLayerImpl* GetTwinLayer() { return twin_layer_; }
   WhichTree GetTree() const;
   bool IsOnActiveOrPendingTree() const;
 
+  // Return the count of tiles on this layer that meet both of the following
+  // conditions:
+  // 1. The tile is required for activation.
+  // 2. The tile needs initialization (ie, it's not ready to draw).
+  size_t UninitializedTilesRequiredForActivationCount() const {
+    return uninitialized_tiles_required_for_activation_count_;
+  }
+
  protected:
   friend class LayerRasterTileIterator;
 
   PictureLayerImpl(LayerTreeImpl* tree_impl, int id);
   PictureLayerTiling* AddTiling(float contents_scale);
   void RemoveTiling(float contents_scale);
   void RemoveAllTilings();
   void SyncFromActiveLayer(const PictureLayerImpl* other);
   void ManageTilings(bool animating_transform_to_screen,
                      float maximum_animation_contents_scale);
   bool ShouldHaveLowResTiling() const {
     return should_use_low_res_tiling_ && !ShouldUseGpuRasterization();
   }
   virtual bool ShouldAdjustRasterScale(
       bool animating_transform_to_screen) const;
   virtual void RecalculateRasterScales(bool animating_transform_to_screen,
                                        float maximum_animation_contents_scale);
   void CleanUpTilingsOnActiveLayer(
       std::vector<PictureLayerTiling*> used_tilings);
   float MinimumContentsScale() const;
   float SnappedContentsScale(float new_contents_scale);
   void UpdateLCDTextStatus(bool new_status);
   void ResetRasterScale();
-  void MarkVisibleResourcesAsRequired() const;
+  void MarkVisibleResourcesAsRequired();
   bool MarkVisibleTilesAsRequired(
       PictureLayerTiling* tiling,
       const PictureLayerTiling* optional_twin_tiling,
       float contents_scale,
       const gfx::Rect& rect,
-      const Region& missing_region) const;
+      const Region& missing_region);
 
   void DoPostCommitInitializationIfNeeded() {
     if (needs_post_commit_initialization_)
       DoPostCommitInitialization();
   }
   void DoPostCommitInitialization();
 
   bool CanHaveTilings() const;
   bool CanHaveTilingWithScale(float contents_scale) const;
   void SanityCheckTilingState() const;
@@ skipping 31 matching lines @@
   bool use_gpu_rasterization_;
 
   bool layer_needs_to_register_itself_;
 
   // Save a copy of the visible rect and viewport size of the last frame that
   // has a valid viewport for prioritizing tiles.
   gfx::Rect visible_rect_for_tile_priority_;
   gfx::Size viewport_size_for_tile_priority_;
   gfx::Transform screen_space_transform_for_tile_priority_;
 
+  size_t uninitialized_tiles_required_for_activation_count_;

[enne (OOO), 2014/04/29 19:44:19]

Ah, I think I get it, because TileManager has no global pass over all tiles,
then it doesn't know how many tiles are required for activation anymore, and the
layer has to keep track of that.

[vmpstr, 2014/04/29 22:56:20]

Ya, that's exactly right. The plan is to not have this check in AssignGpuMemory
at all, and instead the tile manager will check this before sending activation
signals to check whether it can actually activate. This is just a first step
that makes it possible to not iterate every tile.

+
   friend class PictureLayer;
   DISALLOW_COPY_AND_ASSIGN(PictureLayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_PICTURE_LAYER_IMPL_H_