docs/2016-11-03-routing.md

+---
+layout: post
+title: Way finding
+subtitle: routing
+#bigimg: /img/jupedsim_small.png
+permalink: 2016-11-03-routing.html
+---
+
+
+
+Different router are implemented. However: 
+
+<div class="alert alert-danger">
+  <strong>Refactoring! </strong>Actually the router-class is undergoing a major refactoring ...
+</div>
+
+
+
+## Floorfield Router
+
+The floorfield-router is our latest router, which uses floorfields 
+to calculate the distances among the doors of the same `subroom`. 
+The major difference to any other router is, that it does __not__ 
+need convex subrooms/rooms any longer. There is no need for adding 
+helplines.
+
+It fills an adjacency matrix and calculates global-shortest paths via the
+Floyd-Warshall algorithm.
+
+The floorfield-router will give intermediate targets within the`subroom`
+of each agent. It works in combination with exit strategies 8 and 9.[^str_8_9] 
+
+
+<div class="alert alert-info">
+  <strong>3D geometries:  </strong> To use it successfully in multi-storage buildings, the user must provide 
+a geometry file, where stair-cases (or any other structur), which connects 
+two floors/levels <b>must</b> be a separate room. Further, that room 
+<b>must</b> only connect two levels. Rooms stretching over more than 
+2 levels are not valid.
+</div>
+
+
+If there are two points with the same ($$x, y$$)-coordinates, which differ 
+only in the $$z$$-coordinate, the router will face problems, thus we defined 
+the restriction above. That should avoid any such cases.
+
+The floorfield router provides one mode: ```ff_global_shortest```
+
+```ff_local_shortest``` and ```ff_quickest``` will follow shortly.
+
+<div class="alert alert-info">
+  <strong>Important! </strong>If you use a router, which allows non-convex subrooms/rooms, you should use an exit-strategy, 
+which also allows non-convex subrooms/rooms. 
+Exit-strategies 8 and 9 will work best with the floorfield router.
+</div>
+
+
+Following snippet is a definition example of the routing information:
+
+```xml
+<route_choice_models>
+  <router router_id="1" description="ff_global_shortest">
+  </router>
+
+  <!-- Not yet implemented -->
+  <!--router router_id="2" description="ff_local_shortest">
+  </router--> 
+  <!-- Not yet implemented -->
+  <!--router router_id="3" description="ff_quickest">
+  </router-->
+</route_choice_models>
+```
+
+## Global shortest path
+
+At the beginning of the simulation, the Dijkstra algorithm is used to
+build a network which is then cached and used through the simulation
+life time.
+
+Detailed information about the aforementioned models
+are presented in: [KemlohWagoum2012a][#KemlohWagoum2012a]
+
+Following snippet is a definition example of the routing information:
+
+```xml
+<route_choice_models>
+  <router router_id="1" description="global_shortest">
+    <parameters>
+      <navigation_lines file="routing.xml" />
+    </parameters>
+  </router>
+</route_choice_models>
+```
+
+## The cognitive map
+See this [talk](http://www.citg.tudelft.nl/fileadmin/Faculteit/CiTG/Over_de_faculteit/Afdelingen/Afdeling_Transport_en_Planning/conference/tgf15/presentations/wednesday/session_a/Andresen_tgf2015.pdf) to get the idea
+
+[Smoke sensor documentation in JPSfire](https://cst.version.fz-juelich.de/jupedsim/JPSfire)
+
+```xml
+<router router_id="7" description="cognitive_map">
+  <sensors>
+      <sensor sensor_id="1" description="Room2Corridor"/>
+      <sensor sensor_id="2" description="Smoke" p_field_path="D:\JuPedSim\jpscore\inputfiles\cognitive_map\pFields\" update_time="30" final_time="300"/>
+  </sensors>
+  <cognitive_map status="complete" />
+</router>
+```
+
+## Updates
+For current development updates, please check this [issue](https://cst.version.fz-juelich.de/jupedsim/jpscore/issues/127) on our GitLab Repo.
+
+
+[^str_8_9]: If convex subrooms are provided, any exit strategy will work. 
+      In these special cases, global router will be faster in computation time.
+
+
+[#KemlohWagoum2012a]: dx.doi.org/10.1142%2FS0219525912500294 "Kemloh et al "Modeling the dynamic route choice of pedestrians to assess the criticality of building evacuation. Advances in Complex Systems. 2012"
+