Reland "Raster display item lists via a visual rect RTree."

cc/playback/display_item_list.h

Index: cc/playback/display_item_list.h
diff --git a/cc/playback/display_item_list.h b/cc/playback/display_item_list.h
index 83ad4f43de24ccac48a1f5624b3d794e3a1876fc..fcc936f17ed90338a69d28d3ea356abebfa7ef98 100644
--- a/cc/playback/display_item_list.h
+++ b/cc/playback/display_item_list.h
@@ -16,11 +16,13 @@
 #include "base/trace_event/trace_event.h"
 #include "cc/base/cc_export.h"
 #include "cc/base/contiguous_container.h"
+#include "cc/base/rtree.h"
 #include "cc/playback/discardable_image_map.h"
 #include "cc/playback/display_item.h"
 #include "cc/playback/display_item_list_settings.h"
 #include "third_party/skia/include/core/SkPicture.h"
 #include "ui/gfx/geometry/rect.h"
+#include "ui/gfx/geometry/rect_conversions.h"
 
 class SkCanvas;
 class SkPictureRecorder;
@@ -37,13 +39,8 @@ class DisplayItemList;
 class CC_EXPORT DisplayItemList
     : public base::RefCountedThreadSafe<DisplayItemList> {
  public:
-  // Creates a display item list. If picture caching is used, then layer_rect
-  // specifies the cull rect of the display item list (the picture will not
-  // exceed this rect). If picture caching is not used, then the given rect can
-  // be empty.
-  // TODO(vmpstr): Maybe this cull rect can be part of the settings instead.
+  // Creates a display item list.
   static scoped_refptr<DisplayItemList> Create(
-      const gfx::Rect& layer_rect,
       const DisplayItemListSettings& settings);
 
   // Creates a DisplayItemList from a Protobuf.
@@ -65,10 +62,6 @@ class CC_EXPORT DisplayItemList
 
   void Raster(SkCanvas* canvas, SkPicture::AbortCallback* callback) const;
 
-  // This is a fast path for use only if canvas_ is set and
-  // retain_individual_display_items_ is false. This method also updates
-  // approximate_op_count_.
-  void RasterIntoCanvas(const DisplayItem& display_item);
 
   // Because processing happens in these CreateAndAppend functions, all the set
   // up for the item should be done via the args, which is why the return type
@@ -148,15 +141,13 @@ class CC_EXPORT DisplayItemList
   void Finalize();
 
   void SetIsSuitableForGpuRasterization(bool is_suitable) {
-    inputs_.is_suitable_for_gpu_rasterization = is_suitable;
+    inputs_.all_items_are_suitable_for_gpu_rasterization = is_suitable;
   }
   bool IsSuitableForGpuRasterization() const;
   int ApproximateOpCount() const;
   size_t ApproximateMemoryUsage() const;
   bool ShouldBeAnalyzedForSolidColor() const;
 
-  bool RetainsIndividualDisplayItems() const;
-
   std::unique_ptr<base::trace_event::ConvertableToTraceFormat> AsValue(
       bool include_items) const;
 
@@ -167,6 +158,10 @@ class CC_EXPORT DisplayItemList
                                   float raster_scale,
                                   std::vector<DrawImage>* images);
 
+  void SetRetainVisualRectsForTesting(bool retain) {
+    retain_visual_rects_ = retain;
+  }
+
   size_t size() const { return inputs_.items.size(); }
 
   gfx::Rect VisualRectForTesting(int index) {
@@ -182,39 +177,33 @@ class CC_EXPORT DisplayItemList
   }
 
  private:
-  DisplayItemList(gfx::Rect layer_rect,
-                  const DisplayItemListSettings& display_list_settings,
-                  bool retain_individual_display_items);
+  explicit DisplayItemList(
+      const DisplayItemListSettings& display_list_settings);
   ~DisplayItemList();
 
+  RTree rtree_;
+  // For testing purposes only. Whether to keep visual rects across calls to
+  // Finalize().
+  bool retain_visual_rects_ = false;
+
   // If we're currently within a paired display item block, unions the
   // given visual rect with the begin display item's visual rect.
   void GrowCurrentBeginItemVisualRect(const gfx::Rect& visual_rect);
-  void ProcessAppendedItem(const DisplayItem* item);
 
   template <typename DisplayItemType, typename... Args>
   const DisplayItemType& AllocateAndConstruct(Args&&... args) {
     auto* item = &inputs_.items.AllocateAndConstruct<DisplayItemType>(
         std::forward<Args>(args)...);
     approximate_op_count_ += item->ApproximateOpCount();
-    ProcessAppendedItem(item);
     return *item;
   }
 
-  sk_sp<SkPicture> picture_;
-
-  std::unique_ptr<SkPictureRecorder> recorder_;
-
-  bool retain_individual_display_items_;
-  int approximate_op_count_;
-
-  // Memory usage due to the cached SkPicture.
-  size_t picture_memory_usage_;
+  int approximate_op_count_ = 0;
 
   DiscardableImageMap image_map_;
 
   struct Inputs {
-    Inputs(gfx::Rect layer_rect, const DisplayItemListSettings& settings);
+    explicit Inputs(const DisplayItemListSettings& settings);
     ~Inputs();
 
     ContiguousContainer<DisplayItem> items;
@@ -226,8 +215,7 @@ class CC_EXPORT DisplayItemList
     std::vector<gfx::Rect> visual_rects;
     std::vector<size_t> begin_item_indices;
     const DisplayItemListSettings settings;
-    gfx::Rect layer_rect;
-    bool is_suitable_for_gpu_rasterization;
+    bool all_items_are_suitable_for_gpu_rasterization = true;
   };
 
   Inputs inputs_;