In a previous article i wrote about how to use OSM and query the OSM dataset online. It works very well, however i like to use QGIS for my challenges.
In this article i will describe the steps for creating a QGIS installation with the required addons.
What is QGIS?
QGIS is a free and open-source cross-platform desktop geographic information system (GIS) application that supports viewing, editing, and analysis of geospatial datasets (source:https://en.wikipedia.org/wiki/QGIS.
Types of data
QGIS can work with several types of data. The most important for us are raster layers, vector layers and WMS-layers.
A rasterlayer is a rectangular grid of pixels, with each pixel’s color being specified by a number of bits (DN-value). Rasterlayers are resolution dependent. That means that they cannot scale up to an arbitrary resolution without loss of apparent quality (source:https://en.wikipedia.org/wiki/Raster_graphics).
Vector graphics are computer graphics images that are defined in terms of 2D points, which are connected by lines and curves to form polygons and other shapes. Each of these points has a definite position on the x- and y-axis of the work plane and determines the direction of the path; further, each path may have various properties including values for stroke color, shape, curve, thickness, and fill. In other words you can zoom in endless without the loss of quality (source:https://en.wikipedia.org/wiki/Vector_graphics).
WMS-layers are raster layers. Only sent by a webserver. With a WMS layer you can view the google maps or OSM layers in your QGIS (source:https://en.wikipedia.org/wiki/Web_Map_Service).
Installing QGIS
Before using anything, QGIS needs to be downloaded:
Best thing to do is installing the ‘OSGeo4W Network Installer’ when you are using windows. This is the advanced installer with more functionality in the future (download @ https://qgis.org/en/site/forusers/download.html).
Lets install some required addons, or plugins. You want to be able to:
1 use the overpass API
2 being able to hop from QGIS to google’s streetview
3 load several WMS layers
Go to Plugins → Plugins .. install
At the top bar of the plugin menu search and install the following plugins:
1 streetview
2 Quickmap services
3 Quick OSM
Streetview
The streetview plugin makes it possible when scrolling thru a map to jump to a specific location in streetview. This makes it very quick and easy to investigate a specific location. Click on the streetview button (1), next go to a street or area where you want to jump to (2). When releasing the mouse button, the default browser will open in streetview.
Quickmap services
Quickmapservices provides us with easy background layers. Click on the quickmapservices button (A), on the right side of the screen a pop-up search screen will appear. Type the name of the layer, ‘Google Satellite Hybrid’ (B), and click add (C). By now google earth hybrid will be loaded in QGIS (Hybrid is satellite imagery and labels).
Quick OSM
Quick OSM is the osm overpass api plugin for QGIS. With the plugin you should be able to look for features within the OSM dataset. Click on the magnifier icon for opening the plugin. At the 1st inputfield the ‘key’ of the datafield is given and at input 2 the value would be given. For example ‘power’ and ‘substation’. When searching in or near a town you could use field 3 for giving this type of parameters.
Lets say you want to find tattoo shops in the city of Apeldoorn. The key would be ‘shop’, value would be ‘tattoo’ and type ‘Apeldoorn’ at the third line.
