Graphics Reference
In-Depth Information
Obtaining the basemap
To follow through this section of the chapter, you are going to need access to the GDAL
command-line tools. GDAL is probably already installed on your computer, as QGIS
makes use of it. If you don't already have GDAL installed, go to
www.gdal.org
and click on
the
Downloads
link to download and install a copy onto your machine.
One of the challenges of writing a mapping application is to obtain a high-quality basemap
on top of which your geospatial data will be displayed. In our case, we want our basemap
to show an aerial photograph of the forest. We're going to use the Whakarewarewa Forest
in Rotorua, New Zealand, for our ForestTrails application. Fortunately, suitable aerial pho-
tographs are available from the
Land Information New Zealand
website.
Go to the following web page, which provides high-resolution aerial photos for the Bay of
Plenty, New Zealand:
We want to download a basemap that covers the Whakarewarewa forest, which is just south
of the city of Rotorua. In the map on the right-hand side of the page, pan and zoom until
the following area of the map is visible:
