cc/layers/layer_iterator.cc

   1 // Copyright 2012 The Chromium Authors. All rights reserved.
   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/layers/layer_iterator.h"
   6
   7 #include <vector>
   8
   9 #include "cc/layers/layer.h"
  10 #include "cc/layers/layer_impl.h"
  11 #include "cc/layers/render_surface.h"
  12 #include "cc/layers/render_surface_impl.h"
  13
  14 namespace cc {
  15
  16 template <typename LayerType,
  17           typename LayerList,
  18           typename RenderSurfaceType,
  19           typename ActionType>
  20 void LayerIteratorActions::BackToFront::Begin(
  21     LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>* it) {
  22   it->target_render_surface_layer_index_ = 0;
  23   it->current_layer_index_ =
  24       LayerIteratorValue::kLayerIndexRepresentingTargetRenderSurface;
  25
  26   highest_target_render_surface_layer_ = 0;
  27 }
  28
  29 template <typename LayerType,
  30           typename LayerList,
  31           typename RenderSurfaceType,
  32           typename ActionType>
  33 void LayerIteratorActions::BackToFront::End(
  34     LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>* it) {
  35   it->target_render_surface_layer_index_ =
  36       LayerIteratorValue::kInvalidTargetRenderSurfaceLayerIndex;
  37   it->current_layer_index_ = 0;
  38 }
  39
  40 template <typename LayerType,
  41           typename LayerList,
  42           typename RenderSurfaceType,
  43           typename ActionType>
  44 void LayerIteratorActions::BackToFront::Next(
  45     LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>* it) {
  46   // If the current layer has a RS, move to its layer list. Otherwise,
  47   // visit the next layer in the current RS layer list.
  48   if (it->current_layer_represents_contributing_render_surface()) {
  49     // Save our position in the child_layers list for the RenderSurface,
  50     // then jump to the next RenderSurface. Save where we
  51     // came from in the next RenderSurface so we can get back to it.
  52     it->target_render_surface()->current_layer_index_history_ =
  53         it->current_layer_index_;
  54     int previous_target_render_surface_layer =
  55         it->target_render_surface_layer_index_;
  56
  57     it->target_render_surface_layer_index_ =
  58         ++highest_target_render_surface_layer_;
  59     it->current_layer_index_ =
  60         LayerIteratorValue::kLayerIndexRepresentingTargetRenderSurface;
  61
  62     it->target_render_surface()->target_render_surface_layer_index_history_ =
  63         previous_target_render_surface_layer;
  64   } else {
  65     ++it->current_layer_index_;
  66
  67     int target_render_surface_num_children =
  68         it->target_render_surface_children().size();
  69     while (it->current_layer_index_ == target_render_surface_num_children) {
  70       // Jump back to the previous RenderSurface,
  71       // and get back the position where we were in that list,
  72       // and move to the next position there.
  73       if (!it->target_render_surface_layer_index_) {
  74         // End of the list
  75         it->target_render_surface_layer_index_ =
  76             LayerIteratorValue::kInvalidTargetRenderSurfaceLayerIndex;
  77         it->current_layer_index_ = 0;
  78         return;
  79       }
  80       it->target_render_surface_layer_index_ = it->target_render_surface()
  81           ->target_render_surface_layer_index_history_;
  82       it->current_layer_index_ =
  83           it->target_render_surface()->current_layer_index_history_ + 1;
  84
  85       target_render_surface_num_children =
  86           it->target_render_surface_children().size();
  87     }
  88   }
  89 }
  90
  91 template <typename LayerType,
  92           typename LayerList,
  93           typename RenderSurfaceType,
  94           typename ActionType>
  95 void LayerIteratorActions::FrontToBack::Begin(
  96     LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>* it) {
  97   it->target_render_surface_layer_index_ = 0;
  98   it->current_layer_index_ = it->target_render_surface_children().size() - 1;
  99   GoToHighestInSubtree(it);
 100 }
 101
 102 template <typename LayerType,
 103           typename LayerList,
 104           typename RenderSurfaceType,
 105           typename ActionType>
 106 void LayerIteratorActions::FrontToBack::End(
 107     LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>* it) {
 108   it->target_render_surface_layer_index_ =
 109       LayerIteratorValue::kInvalidTargetRenderSurfaceLayerIndex;
 110   it->current_layer_index_ = 0;
 111 }
 112
 113 template <typename LayerType,
 114           typename LayerList,
 115           typename RenderSurfaceType,
 116           typename ActionType>
 117 void LayerIteratorActions::FrontToBack::Next(
 118     LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>* it) {
 119   // Moves to the previous layer in the current RS layer list.
 120   // Then we check if the new current layer has its own RS,
 121   // in which case there are things in that RS layer list that are higher,
 122   // so we find the highest layer in that subtree.
 123   // If we move back past the front of the list,
 124   // we jump up to the previous RS layer list, picking up again where we
 125   // had previously recursed into the current RS layer list.
 126
 127   if (!it->current_layer_represents_target_render_surface()) {
 128     // Subtracting one here will eventually cause the current layer
 129     // to become that layer representing the target render surface.
 130     --it->current_layer_index_;
 131     GoToHighestInSubtree(it);
 132   } else {
 133     while (it->current_layer_represents_target_render_surface()) {
 134       if (!it->target_render_surface_layer_index_) {
 135         // End of the list
 136         it->target_render_surface_layer_index_ =
 137             LayerIteratorValue::kInvalidTargetRenderSurfaceLayerIndex;
 138         it->current_layer_index_ = 0;
 139         return;
 140       }
 141       it->target_render_surface_layer_index_ = it->target_render_surface()
 142           ->target_render_surface_layer_index_history_;
 143       it->current_layer_index_ =
 144           it->target_render_surface()->current_layer_index_history_;
 145     }
 146   }
 147 }
 148
 149 template <typename LayerType,
 150           typename LayerList,
 151           typename RenderSurfaceType,
 152           typename ActionType>
 153 void LayerIteratorActions::FrontToBack::GoToHighestInSubtree(
 154     LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>* it) {
 155   if (it->current_layer_represents_target_render_surface())
 156     return;
 157   while (it->current_layer_represents_contributing_render_surface()) {
 158     // Save where we were in the current target surface, move to the next one,
 159     // and save the target surface that we came from there
 160     // so we can go back to it.
 161     it->target_render_surface()->current_layer_index_history_ =
 162         it->current_layer_index_;
 163     int previous_target_render_surface_layer =
 164         it->target_render_surface_layer_index_;
 165
 166     for (LayerType* layer = it->current_layer();
 167          it->target_render_surface_layer() != layer;
 168          ++it->target_render_surface_layer_index_) {
 169     }
 170     it->current_layer_index_ = it->target_render_surface_children().size() - 1;
 171
 172     it->target_render_surface()->target_render_surface_layer_index_history_ =
 173         previous_target_render_surface_layer;
 174   }
 175 }
 176
 177 // Declare each of the above functions for Layer and LayerImpl classes
 178 // so that they are linked.
 179 template CC_EXPORT void LayerIteratorActions::BackToFront::Begin(
 180     LayerIterator<Layer, RenderSurfaceLayerList, RenderSurface, BackToFront>*
 181         it);
 182 template CC_EXPORT void LayerIteratorActions::BackToFront::End(
 183     LayerIterator<Layer, RenderSurfaceLayerList, RenderSurface, BackToFront>*
 184         it);
 185 template CC_EXPORT void LayerIteratorActions::BackToFront::Next(
 186     LayerIterator<Layer, RenderSurfaceLayerList, RenderSurface, BackToFront>*
 187         it);
 188
 189 template CC_EXPORT void LayerIteratorActions::BackToFront::Begin(
 190     LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, BackToFront>*
 191         it);
 192 template CC_EXPORT void LayerIteratorActions::BackToFront::End(
 193     LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, BackToFront>*
 194         it);
 195 template CC_EXPORT void LayerIteratorActions::BackToFront::Next(
 196     LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, BackToFront>*
 197         it);
 198
 199 template CC_EXPORT void LayerIteratorActions::FrontToBack::Next(
 200     LayerIterator<Layer, RenderSurfaceLayerList, RenderSurface, FrontToBack>*
 201         it);
 202 template CC_EXPORT void LayerIteratorActions::FrontToBack::End(
 203     LayerIterator<Layer, RenderSurfaceLayerList, RenderSurface, FrontToBack>*
 204         it);
 205 template CC_EXPORT void LayerIteratorActions::FrontToBack::Begin(
 206     LayerIterator<Layer, RenderSurfaceLayerList, RenderSurface, FrontToBack>*
 207         it);
 208 template CC_EXPORT void LayerIteratorActions::FrontToBack::GoToHighestInSubtree(
 209     LayerIterator<Layer, RenderSurfaceLayerList, RenderSurface, FrontToBack>*
 210         it);
 211
 212 template CC_EXPORT void LayerIteratorActions::FrontToBack::Next(
 213     LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, FrontToBack>*
 214         it);
 215 template CC_EXPORT void LayerIteratorActions::FrontToBack::End(
 216     LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, FrontToBack>*
 217         it);
 218 template CC_EXPORT void LayerIteratorActions::FrontToBack::Begin(
 219     LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, FrontToBack>*
 220         it);
 221 template CC_EXPORT void LayerIteratorActions::FrontToBack::GoToHighestInSubtree(
 222     LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, FrontToBack>*
 223         it);
 224
 225 }  // namespace cc