Book Image

Mastering Geospatial Development with QGIS 3.x - Third Edition

By : Shammunul Islam, Simon Miles, Kurt Menke, GISP, Richard Smith Jr., GISP, Luigi Pirelli, John Van Hoesen, GISP
Book Image

Mastering Geospatial Development with QGIS 3.x - Third Edition

By: Shammunul Islam, Simon Miles, Kurt Menke, GISP, Richard Smith Jr., GISP, Luigi Pirelli, John Van Hoesen, GISP

Overview of this book

QGIS is an open source solution to GIS and widely used by GIS professionals all over the world. It is the leading alternative to proprietary GIS software. Although QGIS is described as intuitive, it is also, by default, complex. Knowing which tools to use and how to apply them is essential to producing valuable deliverables on time. Starting with a refresher on the QGIS basics and getting you acquainted with the latest QGIS 3.6 updates, this book will take you all the way through to teaching you how to create a spatial database and a GeoPackage. Next, you will learn how to style raster and vector data by choosing and managing different colors. The book will then focus on processing raster and vector data. You will be then taught advanced applications, such as creating and editing vector data. Along with that, you will also learn about the newly updated Processing Toolbox, which will help you develop the advanced data visualizations. The book will then explain to you the graphic modeler, how to create QGIS plugins with PyQGIS, and how to integrate Python analysis scripts with QGIS. By the end of the book, you will understand how to work with all aspects of QGIS and will be ready to use it for any type of GIS work.
Table of Contents (18 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Index

Converting from vector to raster (rasterize)


To convert a vector to a raster format, QGIS provides the Rasterize tool. This tool converts a shapefile to a raster and applies the values in a specified attribute field to the cell values. To access the Rasterize tool, click on Rasterize (Vector to Raster) by navigating to Raster | Conversion.

The Rasterize tool, shown in the following screenshot, uses the Dallas_Land_Cover.shp sample file as input: 

To convert a raster to a vector polygon, some of the available options available are as follows:

  • Input layer: The input vector file to be converted. The tool supports multiple vector formats.
  • Field to use for a burn-in value: The field name from the polygon to be burned into raster.
  • Output raster size units: This tells the unit of raster size.
  • Width/Horizontal resolution: This is the width of the raster file or the output file.
  • Height/Vertical resolution: This is the height of the raster file or the output file.
  • Output extent (xmin, xmax, ymin, ymax): Using...