A host of micro-optimizations and a refactor of TimeForBoundsToIntersect

cc/picture_layer_tiling.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/picture_layer_tiling.h"
 
+#include "base/debug/trace_event.h"
 #include "cc/math_util.h"
 #include "ui/gfx/point_conversions.h"
 #include "ui/gfx/rect_conversions.h"
 #include "ui/gfx/safe_integer_conversions.h"
 #include "ui/gfx/size_conversions.h"
 
 namespace cc {
 
 scoped_ptr<PictureLayerTiling> PictureLayerTiling::Create(
     float contents_scale,
@@ skipping 311 matching lines @@
     gfx::Size last_layer_bounds,
     gfx::Size current_layer_bounds,
     gfx::Size last_layer_content_bounds,
     gfx::Size current_layer_content_bounds,
     float last_layer_contents_scale,
     float current_layer_contents_scale,
     const gfx::Transform& last_screen_transform,
     const gfx::Transform& current_screen_transform,
     int current_source_frame_number,
     double current_frame_time) {
+  TRACE_EVENT0("cc", "PictureLayerTiling::UpdateTilePriorities");
   gfx::Rect content_rect = ContentRect();
   if (content_rect.IsEmpty())
     return;
 
   bool first_update_in_new_source_frame =
       current_source_frame_number != last_source_frame_number_;
 
   bool first_update_in_new_impl_frame =
       current_frame_time != last_impl_frame_time_;
 
@@ skipping 70 matching lines @@
           tiling_data_.TileBounds(iter.index_x(), iter.index_y());
       gfx::RectF current_screen_rect = gfx::ScaleRect(
           tile_bounds,
           current_scale,
           current_scale) + current_offset;
       gfx::RectF last_screen_rect = gfx::ScaleRect(
           tile_bounds,
           last_scale,
           last_scale) + last_offset;
 
+      float distance_to_visible_in_pixels =
+          TilePriority::manhattanDistance(current_screen_rect, view_rect);
+
       float time_to_visible_in_seconds =
           TilePriority::TimeForBoundsToIntersect(
               last_screen_rect, current_screen_rect, time_delta, view_rect);
-      float distance_to_visible_in_pixels =
-          TilePriority::manhattanDistance(current_screen_rect, view_rect);
-
       TilePriority priority(
           resolution_,
           time_to_visible_in_seconds,
           distance_to_visible_in_pixels);
       tile->set_priority(tree, priority);
     }
   }
   else
   {
     for (TilingData::Iterator iter(&tiling_data_, inflated_rect);
@@ skipping 11 matching lines @@
           current_scale);
       gfx::RectF current_screen_rect = MathUtil::mapClippedRect(
           current_screen_transform, current_layer_content_rect);
       gfx::RectF last_layer_content_rect = gfx::ScaleRect(
           tile_bounds,
           last_scale,
           last_scale);
       gfx::RectF last_screen_rect  = MathUtil::mapClippedRect(
           last_screen_transform, last_layer_content_rect);
 
+      float distance_to_visible_in_pixels =
+          TilePriority::manhattanDistance(current_screen_rect, view_rect);
+
       float time_to_visible_in_seconds =
           TilePriority::TimeForBoundsToIntersect(
               last_screen_rect, current_screen_rect, time_delta, view_rect);
-      float distance_to_visible_in_pixels =
-          TilePriority::manhattanDistance(current_screen_rect, view_rect);
 
       TilePriority priority(
           resolution_,
           time_to_visible_in_seconds,
           distance_to_visible_in_pixels);
       tile->set_priority(tree, priority);
     }
   }
 
   last_source_frame_number_ = current_source_frame_number;
   last_impl_frame_time_ = current_frame_time;
 }
 
 void PictureLayerTiling::DidBecomeActive() {
   for (TileMap::const_iterator it = tiles_.begin(); it != tiles_.end(); ++it) {
     it->second->set_priority(ACTIVE_TREE, it->second->priority(PENDING_TREE));
     it->second->set_priority(PENDING_TREE, TilePriority());
 
     // Tile holds a ref onto a picture pile. If the tile never gets invalidated
     // and recreated, then that picture pile ref could exist indefinitely.  To
     // prevent this, ask the client to update the pile to its own ref.  This
     // will cause PicturePileImpls and their clones to get deleted once the
     // corresponding PictureLayerImpl and any in flight raster jobs go out of
     // scope.
     client_->UpdatePile(it->second);
   }
 }
 
 }  // namespace cc