Layer effects in QGis
Since QGis version 2.10 you have at your disposal a powerful tool to format the vector layers symbols. The layer effects provide the ability to add different effects in the rendering chain of a symbol. With…
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How to install QGis Server in Windows 10
If you want to install QGis Server in a Windows computer, you will start a long road full of pitfalls. Firstly, 95% of the available documentation is to perform the installation with Linux. Secondly, WEB searches…
Read MoreHow to find a layer coordinate system with ArcGis 10.X?
Usually, all layers of geographic data have the description of the coordinate system. Unfortunately, this is not always the case. Generally, the problem increases by not being able to contact the producer of the data. Problem…
Read MoreHow to develop a pgrouting application in Windows (7) : OpenLayers 3
With this final article, we get to the end of this series. After setting up the Postgres / Postgis database, we configured Geoserver to assist the results of pgrouting into a WMS lux. All that’s left…
Read MoreHow to develop a pgrouting application in Windows (6): Setting up Geoserver
We have discussed in previous articles how to set up the network data for pgrouting and how to develop a wrapper to search the route between two points. Here we will discuss how to set up…
Read MoreHow to develop an application with pgrouting in Windows (5): writing a Wrapper
A wrapper is a PostgreSQL function that contains pgRouting and PostGIS features easier to use than pgRouting and PostGIS functions straightaway. The pgRouting native functions have been designed to be generic so they can be used…
Read MoreHow to develop an application with pgRouting in Windows (4): catchment areas and isochrones
pgRouting includes a function called pgr_drivingDistance , that, together with three others functions , pgr_withPointsDD , pgr_alphaShape and pgr_pointsAsPolygon , can be used to establish which paths have a certain cost versus a starting or arrival…
Read MoreHow to develop an application with pgrouting in Windows (2): the A-star algorithm
The pgrouting extension offers various algorithms to find the best route: Dijkstra, A *, Ksp, Trsp, … In this article we will discuss in detail the use of a * (A-star). We will continue to use…
Read MoreHow to develop an application with pgrouting in Windows (1)
Here starts a series of articles to set up a routing web application (route calculation) completely autonomous, ie using no web service or API for calculating the route. We will set up the database including the…
Read MoreHow to develop an application with pgrouting in Windows (3): the Dijkstra algorithm
Given a graph and a source vertex in the graph, Dijkstra’s algorithm finds the shortest paths from source to all vertices in the given graph. It takes as input an oriented graph weighted by real positive…
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