cc/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/layer_iterator.h"
   6
   7 #include "cc/layer.h"
   8 #include "cc/layer_impl.h"
   9 #include "cc/render_surface.h"
  10 #include "cc/render_surface_impl.h"
  11
  12 namespace cc {
  13
  14 template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
  15 void LayerIteratorActions::BackToFront::begin(LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
  16 {
  17     it.m_targetRenderSurfaceLayerIndex = 0;
  18     it.m_currentLayerIndex = LayerIteratorValue::LayerIndexRepresentingTargetRenderSurface;
  19
  20     m_highestTargetRenderSurfaceLayer = 0;
  21 }
  22
  23 template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
  24 void LayerIteratorActions::BackToFront::end(LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
  25 {
  26     it.m_targetRenderSurfaceLayerIndex = LayerIteratorValue::InvalidTargetRenderSurfaceLayerIndex;
  27     it.m_currentLayerIndex = 0;
  28 }
  29
  30 template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
  31 void LayerIteratorActions::BackToFront::next(LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
  32 {
  33     // If the current layer has a RS, move to its layer list. Otherwise, visit the next layer in the current RS layer list.
  34     if (it.currentLayerRepresentsContributingRenderSurface()) {
  35         // Save our position in the childLayer list for the RenderSurfaceImpl, then jump to the next RenderSurfaceImpl. Save where we
  36         // came from in the next RenderSurfaceImpl so we can get back to it.
  37         it.targetRenderSurface()->m_currentLayerIndexHistory = it.m_currentLayerIndex;
  38         int previousTargetRenderSurfaceLayer = it.m_targetRenderSurfaceLayerIndex;
  39
  40         it.m_targetRenderSurfaceLayerIndex = ++m_highestTargetRenderSurfaceLayer;
  41         it.m_currentLayerIndex = LayerIteratorValue::LayerIndexRepresentingTargetRenderSurface;
  42
  43         it.targetRenderSurface()->m_targetRenderSurfaceLayerIndexHistory = previousTargetRenderSurfaceLayer;
  44     } else {
  45         ++it.m_currentLayerIndex;
  46
  47         int targetRenderSurfaceNumChildren = it.targetRenderSurfaceChildren().size();
  48         while (it.m_currentLayerIndex == targetRenderSurfaceNumChildren) {
  49             // Jump back to the previous RenderSurfaceImpl, and get back the position where we were in that list, and move to the next position there.
  50             if (!it.m_targetRenderSurfaceLayerIndex) {
  51                 // End of the list
  52                 it.m_targetRenderSurfaceLayerIndex = LayerIteratorValue::InvalidTargetRenderSurfaceLayerIndex;
  53                 it.m_currentLayerIndex = 0;
  54                 return;
  55             }
  56             it.m_targetRenderSurfaceLayerIndex = it.targetRenderSurface()->m_targetRenderSurfaceLayerIndexHistory;
  57             it.m_currentLayerIndex = it.targetRenderSurface()->m_currentLayerIndexHistory + 1;
  58
  59             targetRenderSurfaceNumChildren = it.targetRenderSurfaceChildren().size();
  60         }
  61     }
  62 }
  63
  64 template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
  65 void LayerIteratorActions::FrontToBack::begin(LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
  66 {
  67     it.m_targetRenderSurfaceLayerIndex = 0;
  68     it.m_currentLayerIndex = it.targetRenderSurfaceChildren().size() - 1;
  69     goToHighestInSubtree(it);
  70 }
  71
  72 template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
  73 void LayerIteratorActions::FrontToBack::end(LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
  74 {
  75     it.m_targetRenderSurfaceLayerIndex = LayerIteratorValue::InvalidTargetRenderSurfaceLayerIndex;
  76     it.m_currentLayerIndex = 0;
  77 }
  78
  79 template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
  80 void LayerIteratorActions::FrontToBack::next(LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
  81 {
  82     // Moves to the previous layer in the current RS layer list. Then we check if the
  83     // new current layer has its own RS, in which case there are things in that RS layer list that are higher, so
  84     // we find the highest layer in that subtree.
  85     // If we move back past the front of the list, we jump up to the previous RS layer list, picking up again where we
  86     // had previously recursed into the current RS layer list.
  87
  88     if (!it.currentLayerRepresentsTargetRenderSurface()) {
  89         // Subtracting one here will eventually cause the current layer to become that layer
  90         // representing the target render surface.
  91         --it.m_currentLayerIndex;
  92         goToHighestInSubtree(it);
  93     } else {
  94         while (it.currentLayerRepresentsTargetRenderSurface()) {
  95             if (!it.m_targetRenderSurfaceLayerIndex) {
  96                 // End of the list
  97                 it.m_targetRenderSurfaceLayerIndex = LayerIteratorValue::InvalidTargetRenderSurfaceLayerIndex;
  98                 it.m_currentLayerIndex = 0;
  99                 return;
 100             }
 101             it.m_targetRenderSurfaceLayerIndex = it.targetRenderSurface()->m_targetRenderSurfaceLayerIndexHistory;
 102             it.m_currentLayerIndex = it.targetRenderSurface()->m_currentLayerIndexHistory;
 103         }
 104     }
 105 }
 106
 107 template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
 108 void LayerIteratorActions::FrontToBack::goToHighestInSubtree(LayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
 109 {
 110     if (it.currentLayerRepresentsTargetRenderSurface())
 111         return;
 112     while (it.currentLayerRepresentsContributingRenderSurface()) {
 113         // Save where we were in the current target surface, move to the next one, and save the target surface that we
 114         // came from there so we can go back to it.
 115         it.targetRenderSurface()->m_currentLayerIndexHistory = it.m_currentLayerIndex;
 116         int previousTargetRenderSurfaceLayer = it.m_targetRenderSurfaceLayerIndex;
 117
 118         for (LayerType* layer = it.currentLayer(); it.targetRenderSurfaceLayer() != layer; ++it.m_targetRenderSurfaceLayerIndex) { }
 119         it.m_currentLayerIndex = it.targetRenderSurfaceChildren().size() - 1;
 120
 121         it.targetRenderSurface()->m_targetRenderSurfaceLayerIndexHistory = previousTargetRenderSurfaceLayer;
 122     }
 123 }
 124
 125 typedef std::vector<scoped_refptr<Layer> > LayerList;
 126 typedef std::vector<LayerImpl*> LayerImplList;
 127
 128 // Declare each of the above functions for Layer and LayerImpl classes so that they are linked.
 129 template CC_EXPORT void LayerIteratorActions::BackToFront::begin(LayerIterator<Layer, LayerList, RenderSurface, BackToFront> &);
 130 template CC_EXPORT void LayerIteratorActions::BackToFront::end(LayerIterator<Layer, LayerList, RenderSurface, BackToFront>&);
 131 template CC_EXPORT void LayerIteratorActions::BackToFront::next(LayerIterator<Layer, LayerList, RenderSurface, BackToFront>&);
 132
 133 template CC_EXPORT void LayerIteratorActions::BackToFront::begin(LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, BackToFront>&);
 134 template CC_EXPORT void LayerIteratorActions::BackToFront::end(LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, BackToFront>&);
 135 template CC_EXPORT void LayerIteratorActions::BackToFront::next(LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, BackToFront>&);
 136
 137 template CC_EXPORT void LayerIteratorActions::FrontToBack::next(LayerIterator<Layer, LayerList, RenderSurface, FrontToBack>&);
 138 template CC_EXPORT void LayerIteratorActions::FrontToBack::end(LayerIterator<Layer, LayerList, RenderSurface, FrontToBack>&);
 139 template CC_EXPORT void LayerIteratorActions::FrontToBack::begin(LayerIterator<Layer, LayerList, RenderSurface, FrontToBack>&);
 140 template CC_EXPORT void LayerIteratorActions::FrontToBack::goToHighestInSubtree(LayerIterator<Layer, LayerList, RenderSurface, FrontToBack>&);
 141
 142 template CC_EXPORT void LayerIteratorActions::FrontToBack::next(LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, FrontToBack>&);
 143 template CC_EXPORT void LayerIteratorActions::FrontToBack::end(LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, FrontToBack>&);
 144 template CC_EXPORT void LayerIteratorActions::FrontToBack::begin(LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, FrontToBack>&);
 145 template CC_EXPORT void LayerIteratorActions::FrontToBack::goToHighestInSubtree(LayerIterator<LayerImpl, LayerImplList, RenderSurfaceImpl, FrontToBack>&);
 146
 147 }  // namespace cc