Because geospatial data is almost impossible to understand until it is displayed, the use of maps to visually represent spatial data is an extremely important topic. In this chapter, we will look at Mapnik, a powerful Python library for transforming geospatial data into great-looking maps. In particular, we will look at:
The underlying concepts Mapnik uses to generate maps
An example program using Mapnik to generate a straightforward map
Various data sources that you can use to add geospatial data to your map
How to use rules, filters, and styles to control the map-generation process
The "symbolizers" you can use to add points, lines, polygons, textual labels, and raster images to your maps
How maps and map layers work together to create a map
Ways of rendering a map into an image file