9. Using Qgis

Other kind of functions are pl/pgsql. As applications requirements become more complex, using previously defined functions becomes necessary.

Chapter Contents

• Using Qgis

  • Set Up QGIS

  • Add a postGIS Layer

  • Format a Routing Layer

  • Copy/Paste Format

  • Save the project

9.1. Set Up QGIS

Graphs have a set of edges and set of vertices associated to it. osm2pgrouting provides the ways_vertices_pgr table which is associated with the ways table. When a subset of edges is used like in vehicle_net or in small_net, the set of vertices associated to each one must be used in order to, for example, locate the nearest vertex to a lat/lon location.

1. Launch QGIS from Geospatial ‣ Desktop GIS ‣ QGIS and select Project ‣ Open from the menu bar.

   

   Note

   The location of QGIS may vary.

   The workshop instructions are based on QGIS 2.14 Essen

   

2. Close the broswer pannel

   

3. Connect to a posgGIS enabeled potsgreSQL database clicking on Add postGIS layer

   

4. Create a new connection clicking on New

   

5. Fill the information and test the connection

   

   Name city_routing

   Host localhost

   Port 5432

   Database city_routing

   User name user

   Password user

6. Allow qgis to remember login and password

   

9.2. Add a postGIS Layer

Click Connect and a list of tables and views from the database will show.

It is necessaary to select the column that has a distinct unique value:

• seq on the routing views

• gid on the data views

9.3. Format a Routing Layer

1. Choose a routing view, Right click ‣ Zoom to Layer

   

2. Right click ‣ Properties

   

3. Style ‣ Color

   

4. Style ‣ + ‣ Symbol Layer Type ‣ Marker line

   

5. Apply ‣ Close

9.4. Copy/Paste Format

1. Choose a formmated layer and Right click ‣ Styles ‣ Copy Styles

   

2. Choose another layer and Right click ‣ Styles ‣ Paste Styles

   

9.5. Save the project

1. Project ‣ Save As …

   

2. Navigate to: User ‣ Desktop ‣ workshop and save pgrouting-Bucharest-Example