OpenTTD Source  12.0-beta2
linkgraph.cpp
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1 /*
2  * This file is part of OpenTTD.
3  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
4  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
6  */
7 
10 #include "../stdafx.h"
11 #include "../core/pool_func.hpp"
12 #include "linkgraph.h"
13 
14 #include "../safeguards.h"
15 
16 /* Initialize the link-graph-pool */
17 LinkGraphPool _link_graph_pool("LinkGraph");
19 
20 
26 inline void LinkGraph::BaseNode::Init(TileIndex xy, StationID st, uint demand)
27 {
28  this->xy = xy;
29  this->supply = 0;
30  this->demand = demand;
31  this->station = st;
32  this->last_update = INVALID_DATE;
33 }
34 
39 {
40  this->capacity = 0;
41  this->usage = 0;
42  this->travel_time_sum = 0;
45  this->next_edge = INVALID_NODE;
46 }
47 
53 void LinkGraph::ShiftDates(int interval)
54 {
55  this->last_compression += interval;
56  for (NodeID node1 = 0; node1 < this->Size(); ++node1) {
57  BaseNode &source = this->nodes[node1];
58  if (source.last_update != INVALID_DATE) source.last_update += interval;
59  for (NodeID node2 = 0; node2 < this->Size(); ++node2) {
60  BaseEdge &edge = this->edges[node1][node2];
62  if (edge.last_restricted_update != INVALID_DATE) edge.last_restricted_update += interval;
63  }
64  }
65 }
66 
67 void LinkGraph::Compress()
68 {
69  this->last_compression = (_date + this->last_compression) / 2;
70  for (NodeID node1 = 0; node1 < this->Size(); ++node1) {
71  this->nodes[node1].supply /= 2;
72  for (NodeID node2 = 0; node2 < this->Size(); ++node2) {
73  BaseEdge &edge = this->edges[node1][node2];
74  if (edge.capacity > 0) {
75  edge.capacity = std::max(1U, edge.capacity / 2);
76  edge.usage /= 2;
77  }
78  if (edge.travel_time_sum > 0) {
79  edge.travel_time_sum = std::max(1ULL, edge.travel_time_sum / 2);
80  }
81  }
82  }
83 }
84 
90 {
91  Date age = _date - this->last_compression + 1;
92  Date other_age = _date - other->last_compression + 1;
93  NodeID first = this->Size();
94  for (NodeID node1 = 0; node1 < other->Size(); ++node1) {
95  Station *st = Station::Get(other->nodes[node1].station);
96  NodeID new_node = this->AddNode(st);
97  this->nodes[new_node].supply = LinkGraph::Scale(other->nodes[node1].supply, age, other_age);
98  st->goods[this->cargo].link_graph = this->index;
99  st->goods[this->cargo].node = new_node;
100  for (NodeID node2 = 0; node2 < node1; ++node2) {
101  BaseEdge &forward = this->edges[new_node][first + node2];
102  BaseEdge &backward = this->edges[first + node2][new_node];
103  forward = other->edges[node1][node2];
104  backward = other->edges[node2][node1];
105  forward.capacity = LinkGraph::Scale(forward.capacity, age, other_age);
106  forward.usage = LinkGraph::Scale(forward.usage, age, other_age);
107  forward.travel_time_sum = LinkGraph::Scale(forward.travel_time_sum, age, other_age);
108  if (forward.next_edge != INVALID_NODE) forward.next_edge += first;
109  backward.capacity = LinkGraph::Scale(backward.capacity, age, other_age);
110  backward.usage = LinkGraph::Scale(backward.usage, age, other_age);
111  backward.travel_time_sum = LinkGraph::Scale(backward.travel_time_sum, age, other_age);
112  if (backward.next_edge != INVALID_NODE) backward.next_edge += first;
113  }
114  BaseEdge &new_start = this->edges[new_node][new_node];
115  new_start = other->edges[node1][node1];
116  if (new_start.next_edge != INVALID_NODE) new_start.next_edge += first;
117  }
118  delete other;
119 }
120 
125 void LinkGraph::RemoveNode(NodeID id)
126 {
127  assert(id < this->Size());
128 
129  NodeID last_node = this->Size() - 1;
130  for (NodeID i = 0; i <= last_node; ++i) {
131  (*this)[i].RemoveEdge(id);
132  BaseEdge *node_edges = this->edges[i];
133  NodeID prev = i;
134  NodeID next = node_edges[i].next_edge;
135  while (next != INVALID_NODE) {
136  if (next == last_node) {
137  node_edges[prev].next_edge = id;
138  break;
139  }
140  prev = next;
141  next = node_edges[prev].next_edge;
142  }
143  node_edges[id] = node_edges[last_node];
144  }
145  Station::Get(this->nodes[last_node].station)->goods[this->cargo].node = id;
146  /* Erase node by swapping with the last element. Node index is referenced
147  * directly from station goods entries so the order and position must remain. */
148  this->nodes[id] = this->nodes.back();
149  this->nodes.pop_back();
150  this->edges.EraseColumn(id);
151  /* Not doing EraseRow here, as having the extra invalid row doesn't hurt
152  * and removing it would trigger a lot of memmove. The data has already
153  * been copied around in the loop above. */
154 }
155 
164 NodeID LinkGraph::AddNode(const Station *st)
165 {
166  const GoodsEntry &good = st->goods[this->cargo];
167 
168  NodeID new_node = this->Size();
169  this->nodes.emplace_back();
170  /* Avoid reducing the height of the matrix as that is expensive and we
171  * most likely will increase it again later which is again expensive. */
172  this->edges.Resize(new_node + 1U, std::max(new_node + 1U, this->edges.Height()));
173 
174  this->nodes[new_node].Init(st->xy, st->index,
176 
177  BaseEdge *new_edges = this->edges[new_node];
178 
179  /* Reset the first edge starting at the new node */
180  new_edges[new_node].next_edge = INVALID_NODE;
181 
182  for (NodeID i = 0; i <= new_node; ++i) {
183  new_edges[i].Init();
184  this->edges[i][new_node].Init();
185  }
186  return new_node;
187 }
188 
197 void LinkGraph::Node::AddEdge(NodeID to, uint capacity, uint usage, uint32 travel_time, EdgeUpdateMode mode)
198 {
199  assert(this->index != to);
200  BaseEdge &edge = this->edges[to];
201  BaseEdge &first = this->edges[this->index];
202  edge.capacity = capacity;
203  edge.usage = usage;
204  edge.travel_time_sum = travel_time * capacity;
205  edge.next_edge = first.next_edge;
206  first.next_edge = to;
208  if (mode & EUM_RESTRICTED) edge.last_restricted_update = _date;
209 }
210 
218 void LinkGraph::Node::UpdateEdge(NodeID to, uint capacity, uint usage, uint32 travel_time, EdgeUpdateMode mode)
219 {
220  assert(capacity > 0);
221  assert(usage <= capacity);
222  if (this->edges[to].capacity == 0) {
223  this->AddEdge(to, capacity, usage, travel_time, mode);
224  } else {
225  (*this)[to].Update(capacity, usage, travel_time, mode);
226  }
227 }
228 
234 {
235  if (this->index == to) return;
236  BaseEdge &edge = this->edges[to];
237  edge.capacity = 0;
240  edge.usage = 0;
241  edge.travel_time_sum = 0;
242 
243  NodeID prev = this->index;
244  NodeID next = this->edges[this->index].next_edge;
245  while (next != INVALID_NODE) {
246  if (next == to) {
247  /* Will be removed, skip it. */
248  this->edges[prev].next_edge = edge.next_edge;
249  edge.next_edge = INVALID_NODE;
250  break;
251  } else {
252  prev = next;
253  next = this->edges[next].next_edge;
254  }
255  }
256 }
257 
268 void LinkGraph::Edge::Update(uint capacity, uint usage, uint32 travel_time, EdgeUpdateMode mode)
269 {
270  assert(this->edge.capacity > 0);
271  assert(capacity >= usage);
272 
273  if (mode & EUM_INCREASE) {
274  if (this->edge.travel_time_sum == 0) {
275  this->edge.travel_time_sum = (this->edge.capacity + capacity) * travel_time;
276  } else if (travel_time == 0) {
277  this->edge.travel_time_sum += this->edge.travel_time_sum / this->edge.capacity * capacity;
278  } else {
279  this->edge.travel_time_sum += travel_time * capacity;
280  }
281  this->edge.capacity += capacity;
282  this->edge.usage += usage;
283  } else if (mode & EUM_REFRESH) {
284  if (this->edge.travel_time_sum == 0) {
285  this->edge.capacity = std::max(this->edge.capacity, capacity);
286  this->edge.travel_time_sum = travel_time * this->edge.capacity;
287  } else if (capacity > this->edge.capacity) {
288  this->edge.travel_time_sum = this->edge.travel_time_sum / this->edge.capacity * capacity;
289  this->edge.capacity = capacity;
290  }
291  this->edge.usage = std::max(this->edge.usage, usage);
292  }
293  if (mode & EUM_UNRESTRICTED) this->edge.last_unrestricted_update = _date;
294  if (mode & EUM_RESTRICTED) this->edge.last_restricted_update = _date;
295 }
296 
302 void LinkGraph::Init(uint size)
303 {
304  assert(this->Size() == 0);
305  this->edges.Resize(size, size);
306  this->nodes.resize(size);
307 
308  for (uint i = 0; i < size; ++i) {
309  this->nodes[i].Init();
310  BaseEdge *column = this->edges[i];
311  for (uint j = 0; j < size; ++j) column[j].Init();
312  }
313 }
TileIndex
uint32 TileIndex
The index/ID of a Tile.
Definition: tile_type.h:83
Station::goods
GoodsEntry goods[NUM_CARGO]
Goods at this station.
Definition: station_base.h:476
LinkGraph::edges
EdgeMatrix edges
Edges in the component.
Definition: linkgraph.h:543
LinkGraph
A connected component of a link graph.
Definition: linkgraph.h:39
LinkGraph::BaseEdge::usage
uint usage
Usage of the link.
Definition: linkgraph.h:64
LinkGraph::nodes
NodeVector nodes
Nodes in the component.
Definition: linkgraph.h:542
Station
Station data structure.
Definition: station_base.h:447
EUM_UNRESTRICTED
@ EUM_UNRESTRICTED
Use unrestricted link.
Definition: linkgraph_type.h:56
Pool::PoolItem<&_link_graph_pool >::index
Tindex index
Index of this pool item.
Definition: pool_type.hpp:235
HasBit
static bool HasBit(const T x, const uint8 y)
Checks if a bit in a value is set.
Definition: bitmath_func.hpp:103
LinkGraph::BaseEdge::Init
void Init()
Create an edge.
Definition: linkgraph.cpp:38
LinkGraph::Scale
static uint Scale(uint val, uint target_age, uint orig_age)
Scale a value from a link graph of age orig_age for usage in one of age target_age.
Definition: linkgraph.h:461
EUM_INCREASE
@ EUM_INCREASE
Increase capacity.
Definition: linkgraph_type.h:53
SpecializedStation< Station, false >::Get
static Station * Get(size_t index)
Gets station with given index.
Definition: base_station_base.h:219
LinkGraph::Size
NodeID Size() const
Get the current size of the component.
Definition: linkgraph.h:505
LinkGraph::RemoveNode
void RemoveNode(NodeID id)
Remove a node from the link graph by overwriting it with the last node.
Definition: linkgraph.cpp:125
LinkGraph::Node::UpdateEdge
void UpdateEdge(NodeID to, uint capacity, uint usage, uint32 time, EdgeUpdateMode mode)
Creates an edge if none exists yet or updates an existing edge.
Definition: linkgraph.cpp:218
LinkGraph::Init
void Init(uint size)
Resize the component and fill it with empty nodes and edges.
Definition: linkgraph.cpp:302
GoodsEntry::status
byte status
Status of this cargo, see GoodsEntryStatus.
Definition: station_base.h:223
EdgeUpdateMode
EdgeUpdateMode
Special modes for updating links.
Definition: linkgraph_type.h:52
LinkGraph::BaseNode::last_update
Date last_update
When the supply was last updated.
Definition: linkgraph.h:52
SmallMatrix::Resize
void Resize(uint new_width, uint new_height)
Set the size to a specific width and height, preserving item positions as far as possible in the proc...
Definition: smallmatrix_type.hpp:214
_date
Date _date
Current date in days (day counter)
Definition: date.cpp:28
LinkGraph::BaseEdge::capacity
uint capacity
Capacity of the link.
Definition: linkgraph.h:63
GoodsEntry::node
NodeID node
ID of node in link graph referring to this goods entry.
Definition: station_base.h:255
Date
int32 Date
The type to store our dates in.
Definition: date_type.h:14
LinkGraph::BaseEdge
An edge in the link graph.
Definition: linkgraph.h:62
SmallMatrix::EraseColumn
void EraseColumn(uint x)
Erase a column, replacing it with the last one.
Definition: smallmatrix_type.hpp:131
GoodsEntry::link_graph
LinkGraphID link_graph
Link graph this station belongs to.
Definition: station_base.h:254
EUM_REFRESH
@ EUM_REFRESH
Refresh capacity.
Definition: linkgraph_type.h:54
_link_graph_pool
LinkGraphPool _link_graph_pool("LinkGraph")
The actual pool with link graphs.
LinkGraph::Edge::Update
void Update(uint capacity, uint usage, uint32 time, EdgeUpdateMode mode)
Update an edge.
Definition: linkgraph.cpp:268
LinkGraph::Node::AddEdge
void AddEdge(NodeID to, uint capacity, uint usage, uint32 time, EdgeUpdateMode mode)
Fill an edge with values from a link.
Definition: linkgraph.cpp:197
LinkGraph::ShiftDates
void ShiftDates(int interval)
Shift all dates by given interval.
Definition: linkgraph.cpp:53
LinkGraph::BaseEdge::last_unrestricted_update
Date last_unrestricted_update
When the unrestricted part of the link was last updated.
Definition: linkgraph.h:66
GoodsEntry
Stores station stats for a single cargo.
Definition: station_base.h:167
Pool
Base class for all pools.
Definition: pool_type.hpp:81
LinkGraph::AddNode
NodeID AddNode(const Station *st)
Add a node to the component and create empty edges associated with it.
Definition: linkgraph.cpp:164
LinkGraph::Node::RemoveEdge
void RemoveEdge(NodeID to)
Remove an outgoing edge from this node.
Definition: linkgraph.cpp:233
INVALID_DATE
static const Date INVALID_DATE
Representation of an invalid date.
Definition: date_type.h:111
LinkGraph::cargo
CargoID cargo
Cargo of this component's link graph.
Definition: linkgraph.h:540
LinkGraph::last_compression
Date last_compression
Last time the capacities and supplies were compressed.
Definition: linkgraph.h:541
GoodsEntry::GES_ACCEPTANCE
@ GES_ACCEPTANCE
Set when the station accepts the cargo currently for final deliveries.
Definition: station_base.h:174
linkgraph.h
LinkGraph::BaseEdge::travel_time_sum
uint64 travel_time_sum
Sum of the travel times of the link, in ticks.
Definition: linkgraph.h:65
LinkGraph::Merge
void Merge(LinkGraph *other)
Merge a link graph with another one.
Definition: linkgraph.cpp:89
BaseStation::xy
TileIndex xy
Base tile of the station.
Definition: base_station_base.h:53
EUM_RESTRICTED
@ EUM_RESTRICTED
Use restricted link.
Definition: linkgraph_type.h:55
INSTANTIATE_POOL_METHODS
#define INSTANTIATE_POOL_METHODS(name)
Force instantiation of pool methods so we don't get linker errors.
Definition: pool_func.hpp:224
LinkGraph::BaseEdge::last_restricted_update
Date last_restricted_update
When the restricted part of the link was last updated.
Definition: linkgraph.h:67
SmallMatrix::capacity
uint capacity
The available space for storing items.
Definition: smallmatrix_type.hpp:43
LinkGraph::BaseNode
Node of the link graph.
Definition: linkgraph.h:47
LinkGraph::BaseEdge::next_edge
NodeID next_edge
Destination of next valid edge starting at the same source node.
Definition: linkgraph.h:68