Adding a grid to the map
An annotated reference grid is useful for map products used to locate features. This recipe teaches you how to add both reference lines on a map and annotations for the lines around the edges of the map.
Getting ready
You will need a shapefile for this map from https://github.com/GeospatialPython/Learn/raw/master/Mississippi.zip, and you need to extract it to your qgis_data directory in a subdirectory named ms.
As with the previous recipes in this chapter, we will use the MapComposer library from https://github.com/GeospatialPython/Learn/raw/master/MapComposer.py, to simplify the creation of the map composition.
Place the file in the .qgis2/python directory within your home directory.
How to do it...
In this recipe, the general steps are to create the map composition, establish the overall grid parameters, define the grid line placement, and then style the grid and annotations. To do this, we need to perform the following steps:
- First, we need to import all the GUI libraries...
