Introduction
This chapter talks about vector layers. In addition to raster, vector information is the other important type of information we can work with in a GIS system.
The chapter tries to summarize the most common and important recipes you may need to work with in OpenLayers.
In GIS, a real-world phenomenon is represented by the concept of a feature. It can be a place—like a city or a village—it can be a road or a railway, it can be a region, a lake, the border of a country, or something similar.
Every feature has a set of attributes: population, length, and so on. It is represented visually by a geometrical symbol: point, line, polygon, and so on, using some visual style: color, radius, width, and so on.
As you can see, there are many concepts to take into account when working with vector information. Fortunately, OpenLayers provides us classes to work with them. We will learn more about these in this chapter.
The base class for vector layers is OpenLayers.Layer.Vector
class, which defines...