src/linkgraph/flowmapper.cpp

   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
   8 /** @file flowmapper.cpp Definition of flowmapper. */
   9
  10 #include "../stdafx.h"
  11 #include "flowmapper.h"
  12
  13 #include "../safeguards.h"
  14
  15 /**
  16  * Map the paths generated by the MCF solver into flows associated with nodes.
  17  * @param job the link graph component to be used.
  18  */
  19 void FlowMapper::Run(LinkGraphJob &job) const
  20 {
  21         for (NodeID node_id = 0; node_id < job.Size(); ++node_id) {
  22                 Node prev_node = job[node_id];
  23                 StationID prev = prev_node.Station();
  24                 PathList &paths = prev_node.Paths();
  25                 for (PathList::iterator i = paths.begin(); i != paths.end(); ++i) {
  26                         Path *path = *i;
  27                         uint flow = path->GetFlow();
  28                         if (flow == 0) break;
  29                         Node node = job[path->GetNode()];
  30                         StationID via = node.Station();
  31                         StationID origin = job[path->GetOrigin()].Station();
  32                         assert(prev != via && via != origin);
  33                         /* Mark all of the flow for local consumption at "first". */
  34                         node.Flows().AddFlow(origin, via, flow);
  35                         if (prev != origin) {
  36                                 /* Pass some of the flow marked for local consumption at "prev" on
  37                                  * to this node. */
  38                                 prev_node.Flows().PassOnFlow(origin, via, flow);
  39                         } else {
  40                                 /* Prev node is origin. Simply add flow. */
  41                                 prev_node.Flows().AddFlow(origin, via, flow);
  42                         }
  43                 }
  44         }
  45
  46         for (NodeID node_id = 0; node_id < job.Size(); ++node_id) {
  47                 /* Remove local consumption shares marked as invalid. */
  48                 Node node = job[node_id];
  49                 FlowStatMap &flows = node.Flows();
  50                 flows.FinalizeLocalConsumption(node.Station());
  51                 if (this->scale) {
  52                         /* Scale by time the graph has been running without being compressed. Add 1 to avoid
  53                          * division by 0 if spawn date == last compression date. This matches
  54                          * LinkGraph::Monthly(). */
  55                         uint runtime = job.JoinDate() - job.Settings().recalc_time - job.LastCompression() + 1;
  56                         for (FlowStatMap::iterator i = flows.begin(); i != flows.end(); ++i) {
  57                                 i->second.ScaleToMonthly(runtime);
  58                         }
  59                 }
  60                 /* Clear paths. */
  61                 PathList &paths = node.Paths();
  62                 for (PathList::iterator i = paths.begin(); i != paths.end(); ++i) {
  63                         delete *i;
  64                 }
  65                 paths.clear();
  66         }
  67 }