Book Image

Learning QGIS - Third Edition

By : Anita Graser
Book Image

Learning QGIS - Third Edition

By: Anita Graser

Overview of this book

QGIS is a user-friendly open source geographic information system (GIS) that runs on Linux, Unix, Mac OS X, and Windows. The popularity of open source geographic information systems and QGIS in particular has been growing rapidly over the last few years. Learning QGIS Third Edition is a practical, hands-on guide updated for QGIS 2.14 that provides you with clear, step-by-step exercises to help you apply your GIS knowledge to QGIS. Through clear, practical exercises, this book will introduce you to working with QGIS quickly and painlessly. This book takes you from installing and configuring QGIS to handling spatial data to creating great maps. You will learn how to load and visualize existing spatial data and create data from scratch. You will get to know important plugins, perform common geoprocessing and spatial analysis tasks and automate them with Processing. We will cover how to achieve great cartographic output and print maps. Finally, you will learn how to extend QGIS using Python and even create your own plugin.
Table of Contents (13 chapters)
Learning QGIS Third Edition
About the Author
About the Reviewer

Styling raster layers

After this introduction to data sources, we can create our first map. We will build the map from the bottom up by first loading some background rasters (hillshade and land cover), which we will then overlay with point, line, and polygon layers.

Let's start by loading a land cover and a hillshade from landcover.img and SR_50M_alaska_nad.tif, and then opening the Style section in the layer properties (by going to Layer | Properties or double-clicking on the layer name). QGIS automatically tries to pick a reasonable default render type for both raster layers. Besides these defaults, the following style options are available for raster layers:

  • Multiband color: This style is used if the raster has several bands. This is usually the case with satellite images with multiple bands.

  • Paletted: This style is used if a single-band raster comes with an indexed palette.

  • Singleband gray: If a raster has neither multiple bands nor an indexed palette (this is the case with, for example...