Richfaces Gmap component is a wrapper for the standard Google Map widgets. You can use the whole set of
functionality Google Map API provides for you.
Google Maps API Version 2 Documentation for Google Map API features.
Gmap has built-in Ajax capability. You do not need to uptade the component using reRender to see
the changes. RichFaces Gmap component is good together with Ajax4jsf jsFunction
component that allows to invoke the server side data and convert it into a JSON format.