cc: Plumbing for BeginFrameSource based on Surfaces

cc/surfaces/surface_aggregator.h

 // Copyright 2014 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_SURFACES_SURFACE_AGGREGATOR_H_
 #define CC_SURFACES_SURFACE_AGGREGATOR_H_
 
 #include <set>
 
 #include "base/containers/hash_tables.h"
 #include "base/containers/scoped_ptr_hash_map.h"
 #include "base/memory/scoped_ptr.h"
 #include "cc/quads/draw_quad.h"
 #include "cc/quads/render_pass.h"
 #include "cc/resources/transferable_resource.h"
 #include "cc/surfaces/surface_id.h"
 #include "cc/surfaces/surfaces_export.h"
 
 namespace cc {
 
 class CompositorFrame;
 class DelegatedFrameData;
 class ResourceProvider;
 class Surface;
 class SurfaceDrawQuad;
 class SurfaceManager;
 
+class CC_SURFACES_EXPORT SurfaceAggregatorClient {
+ public:
+  virtual ~SurfaceAggregatorClient() {}
+
+  virtual void AddSurface(Surface* surface) = 0;
+  virtual void RemoveSurface(Surface* surface) = 0;
+};
+
 class CC_SURFACES_EXPORT SurfaceAggregator {
  public:
   typedef base::hash_map<SurfaceId, int> SurfaceIndexMap;
 
-  SurfaceAggregator(SurfaceManager* manager,
+  SurfaceAggregator(SurfaceAggregatorClient* client,

[mithro-old, 2015/10/01 03:00:23]

I *think* it makes sense that a SurfaceAggregator only has a single client. Can
you think of any cases were we might want multiple clients?

[brianderson, 2015/10/07 20:54:48]

It is owned by the Display (which is the SurfaceAggregatorClient), which will
handle the the distribution to multiple Surface classes - so there isn't a need
for SurfaceAggregator itself to have multiple clients.

+                    SurfaceManager* manager,
                     ResourceProvider* provider,
                     bool aggregate_only_damaged);
   ~SurfaceAggregator();
 
   scoped_ptr<CompositorFrame> Aggregate(SurfaceId surface_id);
   void ReleaseResources(SurfaceId surface_id);
   SurfaceIndexMap& previous_contained_surfaces() {
     return previous_contained_surfaces_;
   }
   void SetFullDamageForSurface(SurfaceId surface_id);
@@ skipping 29 matching lines @@
       const base::hash_map<ResourceId, ResourceId>& resource_to_child_map,
       const gfx::Transform& target_transform,
       const ClipData& clip_rect,
       RenderPass* dest_pass,
       SurfaceId surface_id);
   gfx::Rect PrewalkTree(SurfaceId surface_id);
   void CopyPasses(const DelegatedFrameData* frame_data, Surface* surface);
 
   // Remove Surfaces that were referenced before but aren't currently
   // referenced from the ResourceProvider.
-  void RemoveUnreferencedChildren();
+  // Also notifies SurfaceAggregatorClient of newly added and removed
+  // child surfaces.
+  void ProcessAddedAndRemovedSurfaces();
 
   int ChildIdForSurface(Surface* surface);
   gfx::Rect DamageRectForSurface(const Surface* surface,
                                  const RenderPass& source,
-                                 const gfx::Rect& full_rect);
+                                 const gfx::Rect& full_rect) const;
 
+  SurfaceAggregatorClient* client_;  // Outlives this class.
   SurfaceManager* manager_;
   ResourceProvider* provider_;
 
   class RenderPassIdAllocator;
   typedef base::ScopedPtrHashMap<SurfaceId, scoped_ptr<RenderPassIdAllocator>>
       RenderPassIdAllocatorMap;
   RenderPassIdAllocatorMap render_pass_allocator_map_;
   int next_render_pass_id_;
   const bool aggregate_only_damaged_;
 
@@ skipping 29 matching lines @@
 
   // Resource list for the aggregated frame.
   TransferableResourceArray* dest_resource_list_;
 
   DISALLOW_COPY_AND_ASSIGN(SurfaceAggregator);
 };
 
 }  // namespace cc
 
 #endif  // CC_SURFACES_SURFACE_AGGREGATOR_H_