Upstream version 11.39.266.0
[platform/framework/web/crosswalk.git] / src / cc / resources / prioritized_tile_set.cc
1 // Copyright 2013 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/resources/prioritized_tile_set.h"
6
7 #include <algorithm>
8
9 #include "cc/resources/managed_tile_state.h"
10 #include "cc/resources/tile.h"
11
12 namespace cc {
13
14 class BinComparator {
15  public:
16   bool operator()(const Tile* a,
17                   const Tile* b) const {
18     const ManagedTileState& ams = a->managed_state();
19     const ManagedTileState& bms = b->managed_state();
20
21     if (ams.priority_bin != bms.priority_bin)
22       return ams.priority_bin < bms.priority_bin;
23
24     if (ams.required_for_activation != bms.required_for_activation)
25       return ams.required_for_activation;
26
27     if (ams.resolution != bms.resolution)
28       return ams.resolution < bms.resolution;
29
30     if (ams.distance_to_visible != bms.distance_to_visible)
31       return ams.distance_to_visible < bms.distance_to_visible;
32
33     gfx::Rect a_rect = a->content_rect();
34     gfx::Rect b_rect = b->content_rect();
35     if (a_rect.y() != b_rect.y())
36       return a_rect.y() < b_rect.y();
37     return a_rect.x() < b_rect.x();
38   }
39 };
40
41 namespace {
42
43 bool TilePriorityTieBreaker(const Tile* tile_i, const Tile* tile_j) {
44   // When two tiles has same priority use Id as tie breaker.
45   return tile_i->id() < tile_j->id();
46 }
47
48 typedef std::vector<Tile*> TileVector;
49
50 void SortBinTiles(ManagedTileBin bin, TileVector* tiles) {
51   switch (bin) {
52     case NEVER_BIN:
53       break;
54     case NOW_AND_READY_TO_DRAW_BIN:
55       std::sort(tiles->begin(), tiles->end(), TilePriorityTieBreaker);
56       break;
57     case NOW_BIN:
58     case SOON_BIN:
59     case EVENTUALLY_AND_ACTIVE_BIN:
60     case EVENTUALLY_BIN:
61     case AT_LAST_AND_ACTIVE_BIN:
62     case AT_LAST_BIN:
63       std::sort(tiles->begin(), tiles->end(), BinComparator());
64       break;
65     default:
66       NOTREACHED();
67   }
68 }
69
70 }  // namespace
71
72 PrioritizedTileSet::PrioritizedTileSet() {
73   for (int bin = 0; bin < NUM_BINS; ++bin)
74     bin_sorted_[bin] = true;
75 }
76
77 PrioritizedTileSet::~PrioritizedTileSet() {}
78
79 void PrioritizedTileSet::InsertTile(Tile* tile, ManagedTileBin bin) {
80   tiles_[bin].push_back(tile);
81   bin_sorted_[bin] = false;
82 }
83
84 void PrioritizedTileSet::Clear() {
85   for (int bin = 0; bin < NUM_BINS; ++bin) {
86     tiles_[bin].clear();
87     bin_sorted_[bin] = true;
88   }
89 }
90
91 bool PrioritizedTileSet::IsEmpty() {
92   for (int bin = 0; bin < NUM_BINS; ++bin)
93     if (!tiles_[bin].empty())
94       return false;
95
96   return true;
97 }
98
99 void PrioritizedTileSet::SortBinIfNeeded(ManagedTileBin bin) {
100   if (!bin_sorted_[bin]) {
101     SortBinTiles(bin, &tiles_[bin]);
102     bin_sorted_[bin] = true;
103   }
104 }
105
106 PrioritizedTileSet::Iterator::Iterator(
107     PrioritizedTileSet* tile_set, bool use_priority_ordering)
108     : tile_set_(tile_set),
109       current_bin_(NOW_AND_READY_TO_DRAW_BIN),
110       use_priority_ordering_(use_priority_ordering) {
111   if (use_priority_ordering_)
112     tile_set_->SortBinIfNeeded(current_bin_);
113   iterator_ = tile_set->tiles_[current_bin_].begin();
114   if (iterator_ == tile_set_->tiles_[current_bin_].end())
115     AdvanceList();
116 }
117
118 PrioritizedTileSet::Iterator::~Iterator() {}
119
120 void PrioritizedTileSet::Iterator::DisablePriorityOrdering() {
121   use_priority_ordering_ = false;
122 }
123
124 PrioritizedTileSet::Iterator&
125 PrioritizedTileSet::Iterator::operator++() {
126   // We can't increment past the end of the tiles.
127   DCHECK(iterator_ != tile_set_->tiles_[current_bin_].end());
128
129   ++iterator_;
130   if (iterator_ == tile_set_->tiles_[current_bin_].end())
131     AdvanceList();
132   return *this;
133 }
134
135 Tile* PrioritizedTileSet::Iterator::operator*() {
136   DCHECK(iterator_ != tile_set_->tiles_[current_bin_].end());
137   return *iterator_;
138 }
139
140 void PrioritizedTileSet::Iterator::AdvanceList() {
141   DCHECK(iterator_ == tile_set_->tiles_[current_bin_].end());
142
143   while (current_bin_ != NEVER_BIN) {
144     current_bin_ = static_cast<ManagedTileBin>(current_bin_ + 1);
145
146     if (use_priority_ordering_)
147       tile_set_->SortBinIfNeeded(current_bin_);
148
149     iterator_ = tile_set_->tiles_[current_bin_].begin();
150     if (iterator_ != tile_set_->tiles_[current_bin_].end())
151       break;
152   }
153 }
154
155 }  // namespace cc