cc/tiles/tiles_with_resource_iterator.cc

   1 // Copyright 2022 The Chromium Authors
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "cc/tiles/tiles_with_resource_iterator.h"
   6
   7 #include "cc/layers/picture_layer_impl.h"
   8 #include "cc/tiles/picture_layer_tiling_set.h"
   9
  10 namespace cc {
  11
  12 TilesWithResourceIterator::TilesWithResourceIterator(
  13     const std::vector<PictureLayerImpl*>* picture_layers,
  14     const std::vector<PictureLayerImpl*>* secondary_picture_layers)
  15     : picture_layers_(picture_layers),
  16       secondary_picture_layers_(secondary_picture_layers),
  17       active_layers_(picture_layers) {
  18   FindNextInPictureLayers();
  19 }
  20
  21 TilesWithResourceIterator::~TilesWithResourceIterator() = default;
  22
  23 bool TilesWithResourceIterator::AtEnd() const {
  24   return !tile_iterator_.has_value();
  25 }
  26
  27 Tile* TilesWithResourceIterator::GetCurrent() {
  28   return AtEnd() ? nullptr : tile_iterator_->GetCurrent();
  29 }
  30
  31 PrioritizedTile* TilesWithResourceIterator::GetCurrentAsPrioritizedTile() {
  32   if (prioritized_tile_)
  33     return &*prioritized_tile_;
  34   Tile* tile = GetCurrent();
  35   if (!tile)
  36     return nullptr;
  37   PictureLayerTiling* tiling = CurrentPictureLayerTiling();
  38   prioritized_tile_ = tiling->MakePrioritizedTile(
  39       tile, tiling->ComputePriorityRectTypeForTile(tile),
  40       tiling->IsTileOccluded(tile));
  41   return &*prioritized_tile_;
  42 }
  43
  44 bool TilesWithResourceIterator::IsCurrentTileOccluded() {
  45   Tile* tile = GetCurrent();
  46   return tile && tile->tiling()->IsTileOccluded(tile);
  47 }
  48
  49 void TilesWithResourceIterator::Next() {
  50   if (AtEnd())
  51     return;
  52   prioritized_tile_.reset();
  53   DCHECK(tile_iterator_);
  54   tile_iterator_->Next();
  55   if (FindNextInTileIterator())
  56     return;
  57   ++current_picture_layer_tiling_index_;
  58   if (FindNextInPictureLayerTilingSet())
  59     return;
  60   ++current_picture_layer_index_;
  61   if (FindNextInPictureLayers())
  62     return;
  63   // At the end.
  64   DCHECK(AtEnd());
  65 }
  66
  67 bool TilesWithResourceIterator::FindNextInPictureLayers() {
  68   if (FindNextInActiveLayers())
  69     return true;
  70   DCHECK(AtEnd());
  71   if (is_active_layers_secondary_layers_)
  72     return false;
  73   // Finished iterating through primary picture layers. Start iterating
  74   // through secondary layers.
  75   is_active_layers_secondary_layers_ = true;
  76   active_layers_ = secondary_picture_layers_;
  77   if (!active_layers_)
  78     return false;
  79   current_picture_layer_index_ = 0;
  80   return FindNextInActiveLayers();
  81 }
  82
  83 bool TilesWithResourceIterator::FindNextInActiveLayers() {
  84   for (; current_picture_layer_index_ < active_layers_->size();
  85        ++current_picture_layer_index_) {
  86     current_picture_layer_tiling_index_ = 0u;
  87     if (FindNextInPictureLayerTilingSet())
  88       return true;
  89   }
  90   // No more tiles to look at. Reset `tile_iterator_` so that AtEnd() returns
  91   // true.
  92   tile_iterator_.reset();
  93   return false;
  94 }
  95
  96 bool TilesWithResourceIterator::FindNextInPictureLayerTilingSet() {
  97   PictureLayerTilingSet* tiling_set = CurrentPictureLayerTilingSet();
  98   for (; current_picture_layer_tiling_index_ < tiling_set->num_tilings();
  99        ++current_picture_layer_tiling_index_) {
 100     tile_iterator_.emplace(CurrentPictureLayerTiling());
 101     if (FindNextInTileIterator())
 102       return true;
 103     ++current_picture_layer_tiling_index_;
 104   }
 105   return false;
 106 }
 107
 108 bool TilesWithResourceIterator::FindNextInTileIterator() {
 109   for (; !tile_iterator_->AtEnd(); tile_iterator_->Next()) {
 110     Tile* tile = tile_iterator_->GetCurrent();
 111     if (visited_.insert(tile).second && tile->draw_info().has_resource())
 112       return true;
 113   }
 114   return false;
 115 }
 116
 117 PictureLayerTilingSet*
 118 TilesWithResourceIterator::CurrentPictureLayerTilingSet() {
 119   return (*active_layers_)[current_picture_layer_index_]
 120       ->picture_layer_tiling_set();
 121 }
 122
 123 PictureLayerTiling* TilesWithResourceIterator::CurrentPictureLayerTiling() {
 124   return CurrentPictureLayerTilingSet()->tiling_at(
 125       current_picture_layer_tiling_index_);
 126 }
 127
 128 }  // namespace cc