The StyleMap class tells the vector layer what Style objects to use when the features are in a certain 'state', or what OpenLayers refers to as intent. As the previous example showed, there's really not much in using this class. To create a StyleMap object you pass in an intent as the key (as a {String}), and a Style object is used as the value. For example, as in the previous example, 'default' is the desired intent and the vector_style object is the desired style object to use for that intent. This causes the vector_style to be applied to the 'default' intent:
var vector_style_map = new OpenLayers.StyleMap( {'default': vector_style} );The 'intent', short for render intent, is a way to specify how features should be drawn, or what features should look like when in different 'states'. There are only three default intents we can use:
'default': This is the intent used most of the time. If a feature is not in the two next intents, it is in this 'default...