cc: Make tiling interest rect calc based on viewport.

cc/resources/picture_layer_tiling_set.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/resources/picture_layer_tiling_set.h"
 
 #include <limits>
 #include <set>
 #include <vector>
 
@@ skipping 13 matching lines @@
   DCHECK_GT(float2, 0.f);
   return float1 > float2 ? float1 / float2 : float2 / float1;
 }
 
 }  // namespace
 
 // static
 scoped_ptr<PictureLayerTilingSet> PictureLayerTilingSet::Create(
     WhichTree tree,
     PictureLayerTilingClient* client,
-    size_t max_tiles_for_interest_area,
+    float tiling_interest_area_viewport_multiplier,
     float skewport_target_time_in_seconds,
     int skewport_extrapolation_limit_in_content_pixels) {
   return make_scoped_ptr(new PictureLayerTilingSet(
-      tree, client, max_tiles_for_interest_area,
+      tree, client, tiling_interest_area_viewport_multiplier,
       skewport_target_time_in_seconds,
       skewport_extrapolation_limit_in_content_pixels));
 }
 
 PictureLayerTilingSet::PictureLayerTilingSet(
     WhichTree tree,
     PictureLayerTilingClient* client,
-    size_t max_tiles_for_interest_area,
+    float tiling_interest_area_viewport_multiplier,
     float skewport_target_time_in_seconds,
     int skewport_extrapolation_limit_in_content_pixels)
-    : max_tiles_for_interest_area_(max_tiles_for_interest_area),
+    : tiling_interest_area_viewport_multiplier_(
+          tiling_interest_area_viewport_multiplier),
       skewport_target_time_in_seconds_(skewport_target_time_in_seconds),
       skewport_extrapolation_limit_in_content_pixels_(
           skewport_extrapolation_limit_in_content_pixels),
       tree_(tree),
       client_(client) {
 }
 
 PictureLayerTilingSet::~PictureLayerTilingSet() {
 }
 
 void PictureLayerTilingSet::CopyTilingsAndPropertiesFromPendingTwin(
     const PictureLayerTilingSet* pending_twin_set,
     const scoped_refptr<RasterSource>& raster_source,
     const Region& layer_invalidation) {
   if (pending_twin_set->tilings_.empty()) {
     // If the twin (pending) tiling set is empty, it was not updated for the
     // current frame. So we drop tilings from our set as well, instead of
     // leaving behind unshared tilings that are all non-ideal.
     RemoveAllTilings();
     return;
   }
 
   bool tiling_sort_required = false;
   for (PictureLayerTiling* pending_twin_tiling : pending_twin_set->tilings_) {
     float contents_scale = pending_twin_tiling->contents_scale();
     PictureLayerTiling* this_tiling = FindTilingWithScale(contents_scale);
     if (!this_tiling) {
       scoped_ptr<PictureLayerTiling> new_tiling = PictureLayerTiling::Create(
           tree_, contents_scale, raster_source, client_,
-          max_tiles_for_interest_area_, skewport_target_time_in_seconds_,
+          tiling_interest_area_viewport_multiplier_,
+          skewport_target_time_in_seconds_,
           skewport_extrapolation_limit_in_content_pixels_);
       tilings_.push_back(new_tiling.Pass());
       this_tiling = tilings_.back();
       tiling_sort_required = true;
     }
     this_tiling->TakeTilesAndPropertiesFrom(pending_twin_tiling,
                                             layer_invalidation);
   }
 
   if (tiling_sort_required)
@@ skipping 167 matching lines @@
 PictureLayerTiling* PictureLayerTilingSet::AddTiling(
     float contents_scale,
     scoped_refptr<RasterSource> raster_source) {
   for (size_t i = 0; i < tilings_.size(); ++i) {
     DCHECK_NE(tilings_[i]->contents_scale(), contents_scale);
     DCHECK_EQ(tilings_[i]->raster_source(), raster_source.get());
   }
 
   tilings_.push_back(PictureLayerTiling::Create(
       tree_, contents_scale, raster_source, client_,
-      max_tiles_for_interest_area_, skewport_target_time_in_seconds_,
+      tiling_interest_area_viewport_multiplier_,
+      skewport_target_time_in_seconds_,
       skewport_extrapolation_limit_in_content_pixels_));
   PictureLayerTiling* appended = tilings_.back();
 
   tilings_.sort(LargestToSmallestScaleFunctor());
   return appended;
 }
 
 int PictureLayerTilingSet::NumHighResTilings() const {
   return std::count_if(tilings_.begin(), tilings_.end(),
                        [](PictureLayerTiling* tiling) {
@@ skipping 316 matching lines @@
     case LOWER_THAN_LOW_RES:
       range = TilingRange(low_res_range.end, tilings_.size());
       break;
   }
 
   DCHECK_LE(range.start, range.end);
   return range;
 }
 
 }  // namespace cc