Until now, we have been focused on getting GeoServer installed and setting up data sources. Now, it is time for us to get to grips with controlling how GeoServer outputs this data. There are a number of different aspects of GeoServer's output that we can control and manipulate, whether it is simple map styling, dynamic data styling, or feature information manipulation, GeoServer gives us the control that we need to make it fit our needs.
In this chapter, we are going to take an in-depth look at the different ways in which we can control the output of GeoServer; in particular, we will focus on the following topics:
Advanced use of Styled Layer Descriptor files to dynamically generate heat maps
Using Cascaded Style Sheets (CSS) as an alternative styling language to SLDs
Performing per-request styling of map features
Performing per-request filtering of map data
Using Freemarker templates to transform responses to WMS GetFeatureInfo requests
By the end...