OpenTTD Source: src/linkgraph/linkgraph.cpp Source File

OpenTTD Source 1.11.0-RC1

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");
18 INSTANTIATE_POOL_METHODS(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
38 inline void LinkGraph::BaseEdge::Init()
39 {
40 this->capacity = 0;
41 this->usage = 0;
42 this->last_unrestricted_update = INVALID_DATE;
43 this->last_restricted_update = INVALID_DATE;
44 this->next_edge = INVALID_NODE;
45 }
46
52 void LinkGraph::ShiftDates(int interval)
53 {
54 this->last_compression += interval;
55 for (NodeID node1 = 0; node1 < this->Size(); ++node1) {
56 BaseNode &source = this->nodes[node1];
57 if (source.last_update != INVALID_DATE) source.last_update += interval;
58 for (NodeID node2 = 0; node2 < this->Size(); ++node2) {
59 BaseEdge &edge = this->edges[node1][node2];
60 if (edge.last_unrestricted_update != INVALID_DATE) edge.last_unrestricted_update += interval;
61 if (edge.last_restricted_update != INVALID_DATE) edge.last_restricted_update += interval;
62 }
63 }
64 }
65
66 void LinkGraph::Compress()
67 {
68 this->last_compression = (_date + this->last_compression) / 2;
69 for (NodeID node1 = 0; node1 < this->Size(); ++node1) {
70 this->nodes[node1].supply /= 2;
71 for (NodeID node2 = 0; node2 < this->Size(); ++node2) {
72 BaseEdge &edge = this->edges[node1][node2];
73 if (edge.capacity > 0) {
74 edge.capacity = std::max(1U, edge.capacity / 2);
75 edge.usage /= 2;
76 }
77 }
78 }
79 }
80
85 void LinkGraph::Merge(LinkGraph *other)
86 {
87 Date age = _date - this->last_compression + 1;
88 Date other_age = _date - other->last_compression + 1;
89 NodeID first = this->Size();
90 for (NodeID node1 = 0; node1 < other->Size(); ++node1) {
91 Station *st = Station::Get(other->nodes[node1].station);
92 NodeID new_node = this->AddNode(st);
93 this->nodes[new_node].supply = LinkGraph::Scale(other->nodes[node1].supply, age, other_age);
94 st->goods[this->cargo].link_graph = this->index;
95 st->goods[this->cargo].node = new_node;
96 for (NodeID node2 = 0; node2 < node1; ++node2) {
97 BaseEdge &forward = this->edges[new_node][first + node2];
98 BaseEdge &backward = this->edges[first + node2][new_node];
99 forward = other->edges[node1][node2];
100 backward = other->edges[node2][node1];
101 forward.capacity = LinkGraph::Scale(forward.capacity, age, other_age);
102 forward.usage = LinkGraph::Scale(forward.usage, age, other_age);
103 if (forward.next_edge != INVALID_NODE) forward.next_edge += first;
104 backward.capacity = LinkGraph::Scale(backward.capacity, age, other_age);
105 backward.usage = LinkGraph::Scale(backward.usage, age, other_age);
106 if (backward.next_edge != INVALID_NODE) backward.next_edge += first;
107 }
108 BaseEdge &new_start = this->edges[new_node][new_node];
109 new_start = other->edges[node1][node1];
110 if (new_start.next_edge != INVALID_NODE) new_start.next_edge += first;
111 }
112 delete other;
113 }
114
119 void LinkGraph::RemoveNode(NodeID id)
120 {
121 assert(id < this->Size());
122
123 NodeID last_node = this->Size() - 1;
124 for (NodeID i = 0; i <= last_node; ++i) {
125 (*this)[i].RemoveEdge(id);
126 BaseEdge *node_edges = this->edges[i];
127 NodeID prev = i;
128 NodeID next = node_edges[i].next_edge;
129 while (next != INVALID_NODE) {
130 if (next == last_node) {
131 node_edges[prev].next_edge = id;
132 break;
133 }
134 prev = next;
135 next = node_edges[prev].next_edge;
136 }
137 node_edges[id] = node_edges[last_node];
138 }
139 Station::Get(this->nodes[last_node].station)->goods[this->cargo].node = id;
140 /* Erase node by swapping with the last element. Node index is referenced
141 * directly from station goods entries so the order and position must remain. */
142 this->nodes[id] = this->nodes.back();
143 this->nodes.pop_back();
144 this->edges.EraseColumn(id);
145 /* Not doing EraseRow here, as having the extra invalid row doesn't hurt
146 * and removing it would trigger a lot of memmove. The data has already
147 * been copied around in the loop above. */
148 }
149
158 NodeID LinkGraph::AddNode(const Station *st)
159 {
160 const GoodsEntry &good = st->goods[this->cargo];
161
162 NodeID new_node = this->Size();
163 this->nodes.emplace_back();
164 /* Avoid reducing the height of the matrix as that is expensive and we
165 * most likely will increase it again later which is again expensive. */
166 this->edges.Resize(new_node + 1U, std::max(new_node + 1U, this->edges.Height()));
167
168 this->nodes[new_node].Init(st->xy, st->index,
169 HasBit(good.status, GoodsEntry::GES_ACCEPTANCE));
170
171 BaseEdge *new_edges = this->edges[new_node];
172
173 /* Reset the first edge starting at the new node */
174 new_edges[new_node].next_edge = INVALID_NODE;
175
176 for (NodeID i = 0; i <= new_node; ++i) {
177 new_edges[i].Init();
178 this->edges[i][new_node].Init();
179 }
180 return new_node;
181 }
182
191 void LinkGraph::Node::AddEdge(NodeID to, uint capacity, uint usage, EdgeUpdateMode mode)
192 {
193 assert(this->index != to);
194 BaseEdge &edge = this->edges[to];
195 BaseEdge &first = this->edges[this->index];
196 edge.capacity = capacity;
197 edge.usage = usage;
198 edge.next_edge = first.next_edge;
199 first.next_edge = to;
200 if (mode & EUM_UNRESTRICTED) edge.last_unrestricted_update = _date;
201 if (mode & EUM_RESTRICTED) edge.last_restricted_update = _date;
202 }
203
211 void LinkGraph::Node::UpdateEdge(NodeID to, uint capacity, uint usage, EdgeUpdateMode mode)
212 {
213 assert(capacity > 0);
214 assert(usage <= capacity);
215 if (this->edges[to].capacity == 0) {
216 this->AddEdge(to, capacity, usage, mode);
217 } else {
218 (*this)[to].Update(capacity, usage, mode);
219 }
220 }
221
226 void LinkGraph::Node::RemoveEdge(NodeID to)
227 {
228 if (this->index == to) return;
229 BaseEdge &edge = this->edges[to];
230 edge.capacity = 0;
231 edge.last_unrestricted_update = INVALID_DATE;
232 edge.last_restricted_update = INVALID_DATE;
233 edge.usage = 0;
234
235 NodeID prev = this->index;
236 NodeID next = this->edges[this->index].next_edge;
237 while (next != INVALID_NODE) {
238 if (next == to) {
239 /* Will be removed, skip it. */
240 this->edges[prev].next_edge = edge.next_edge;
241 edge.next_edge = INVALID_NODE;
242 break;
243 } else {
244 prev = next;
245 next = this->edges[next].next_edge;
246 }
247 }
248 }
249
259 void LinkGraph::Edge::Update(uint capacity, uint usage, EdgeUpdateMode mode)
260 {
261 assert(this->edge.capacity > 0);
262 assert(capacity >= usage);
263
264 if (mode & EUM_INCREASE) {
265 this->edge.capacity += capacity;
266 this->edge.usage += usage;
267 } else if (mode & EUM_REFRESH) {
268 this->edge.capacity = std::max(this->edge.capacity, capacity);
269 this->edge.usage = std::max(this->edge.usage, usage);
270 }
271 if (mode & EUM_UNRESTRICTED) this->edge.last_unrestricted_update = _date;
272 if (mode & EUM_RESTRICTED) this->edge.last_restricted_update = _date;
273 }
274
280 void LinkGraph::Init(uint size)
281 {
282 assert(this->Size() == 0);
283 this->edges.Resize(size, size);
284 this->nodes.resize(size);
285
286 for (uint i = 0; i < size; ++i) {
287 this->nodes[i].Init();
288 BaseEdge *column = this->edges[i];
289 for (uint j = 0; j < size; ++j) column[j].Init();
290 }
291 }
TileIndex
uint32 TileIndex
The index/ID of a Tile.
Definition: tile_type.h:78
Station::goods
GoodsEntry goods[NUM_CARGO]
Goods at this station.
Definition: station_base.h:479
LinkGraph::edges
EdgeMatrix edges
Edges in the component.
Definition: linkgraph.h:535
LinkGraph::Node::AddEdge
void AddEdge(NodeID to, uint capacity, uint usage, EdgeUpdateMode mode)
Fill an edge with values from a link.
Definition: linkgraph.cpp:191
LinkGraph
A connected component of a link graph.
Definition: linkgraph.h:39
LinkGraph::Node::UpdateEdge
void UpdateEdge(NodeID to, uint capacity, uint usage, EdgeUpdateMode mode)
Creates an edge if none exists yet or updates an existing edge.
Definition: linkgraph.cpp:211
LinkGraph::BaseEdge::usage
uint usage
Usage of the link.
Definition: linkgraph.h:64
LinkGraph::nodes
NodeVector nodes
Nodes in the component.
Definition: linkgraph.h:534
Station
Station data structure.
Definition: station_base.h:450
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:227
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:454
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::RemoveNode
void RemoveNode(NodeID id)
Remove a node from the link graph by overwriting it with the last node.
Definition: linkgraph.cpp:119
LinkGraph::Init
void Init(uint size)
Resize the component and fill it with empty nodes and edges.
Definition: linkgraph.cpp:280
GoodsEntry::status
byte status
Status of this cargo, see GoodsEntryStatus.
Definition: station_base.h:226
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:258
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
LinkGraph::Size
uint Size() const
Get the current size of the component.
Definition: linkgraph.h:498
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:257
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::ShiftDates
void ShiftDates(int interval)
Shift all dates by given interval.
Definition: linkgraph.cpp:52
LinkGraph::BaseEdge::last_unrestricted_update
Date last_unrestricted_update
When the unrestricted part of the link was last updated.
Definition: linkgraph.h:65
GoodsEntry
Stores station stats for a single cargo.
Definition: station_base.h:170
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:158
LinkGraph::Node::RemoveEdge
void RemoveEdge(NodeID to)
Remove an outgoing edge from this node.
Definition: linkgraph.cpp:226
INVALID_DATE
static const Date INVALID_DATE
Representation of an invalid date.
Definition: date_type.h:110
LinkGraph::cargo
CargoID cargo
Cargo of this component's link graph.
Definition: linkgraph.h:532
LinkGraph::Edge::Update
void Update(uint capacity, uint usage, EdgeUpdateMode mode)
Update an edge.
Definition: linkgraph.cpp:259
LinkGraph::last_compression
Date last_compression
Last time the capacities and supplies were compressed.
Definition: linkgraph.h:533
GoodsEntry::GES_ACCEPTANCE
@ GES_ACCEPTANCE
Set when the station accepts the cargo currently for final deliveries.
Definition: station_base.h:177
linkgraph.h
LinkGraph::Merge
void Merge(LinkGraph *other)
Merge a link graph with another one.
Definition: linkgraph.cpp:85
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:66
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:67