![]() This is the conversion of paper maps into maps that can be used in the GIS. Quntum GIS can do everything in this definition so lets pull the definition apart a bit… Capturing mapsīy this, I mean digitizing. What a Geographical Information System?Ī GIS is a computer application that allows you to capture, store, search, manipulate, relate and manage maps and information about them. In order to understand what Quantum GIS is, lets have a quick look at what a Geographical Information System is. Its been around since around 2002 and these days is similarly functional to commercial Geographical Information Systems. ![]() “Big up to QGIS 3 for giving users complete control of their map labels.What is Quantum GIS (QGIS) – its a brand of Geographical Information System that is Open Source and so free. To be fair, manual label placement has been in QGIS v2 for quite some time. ![]() What version 3 did was make it more user friendly by allowing the overrides to be stored with the project. With v2 the user had to add specifically named fields to each layer to enable each icon in the relevant toolbar. Now it’s on all the time and if the user still wishes to store info in the layer or export it that is a provided option. Similarly geometry generators have been in since 2.14(ish?). The general vector editing in Q has come a long way and is far more consistent now. That the trace tool they added in 2.whenever was considerably superior to the one in arc rather highlights the way this has been going to me. Q might not do absolutely everything Arc can but what it can do it generally does better, often much better.ģ.0 was a bit buggy, 3.2 is looking pretty stable so believe it’s not $.QGIS (formerly Quantum GIS) is a full-featured, open-source, cross-platform Geographic Information System. With QGIS you can access up-to-date OSM data whenever you want, select the tags you want to include, and easily export it into an easy-to-use SQLite database or Shapefile. In this chapter we’ll walk through the steps necessary to do this. We assume that you’ve already downloaded and installed QGIS 3.x. If you haven’t already done this, you can download it from. We will use a plugin, QuickOSM, to import data from the OpenStreetMap database. To install this plugin open the Manage Plugins dialogue from the Plugins menu. This will add an entry to the Vector menu Obtaining Data from the Database #WHICH SITE FOR QUANTUM GIS INSTALL# The first thing we will do is get some up-to-date OSM data. The QuickOSM plugin allows us to extract large amounts of data as it uses the Overpass api and not the main OSM database server. Open QGIS and go to Vector -> QuickOSM -> QuickOSM….You can choose from several options here - if your window already displays the extent you want, switch the combobox which by default shows “In” to “Canvas extent”. If you have a layer loaded in QGIS with the correct extent, choose “Layer extent” and select the layer you want to use. Using the default “In” requires that a relation or polygon exists with this name. Otherwise choose “Around” and a node with this name suffices. You can select a perimeter (default 1000m) around this node where data will be loaded from the database. You will be notified when the download is complete.The data are stored in three temporary layers, one for nodes, ways and polygons respectively. There are several options how to obtain ready-made extracts of an area. Once you used QuickOSM OSM files should have been made known to QGIS and you can use the regular vector layer import: You can either use QuickOSM to import it clicking on ‘OSM File’ in the left bar. After clicking “OK” you can close the dialogue and your QGIS window shows the new layers.You can select one or more type layers from that file.In the source field, select your file and click “Add”.Go to Layer -> Add Layer -> Add Vector Layer…. To export a layer activate its context menu and select Export -> Save Features as. You can select from a wide range of formats including Shapefile, GeoJSON, PostgreSQL dump, SQLite. The other options on the dialogue vary depending on the format you selected. You can choose to re-import the exported layer by checking the box at the bottom (activated by default). We cannot give you even a rough overview over what you can do with QGIS and there are many excellent tutorials and books which will guide you step-by-step towards mastering the software. But as OSM data imported by one of the methods described above have their tags encoded in a special way here is an example how to deal with them (for the curious, the example is pitcairn-islands-latest from Geofabrik’s download page for Australia and Oceania).
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