Libraries

The JavaScript code for the Maps API is loaded via a bootstrap URL of the form http://maps.googleapis.com/maps/api/js. This bootstrap request loads all of the main Javascript objects and symbols for use in the Maps API. Some Maps API features are also available in self-contained libraries which are not loaded unless you specifically request them. Breaking up supplemental components into libraries allows the main API to load (and parse) quickly; you only incur the additional overhead of loading and parsing libraries if you need them.

You specify additional libraries to load within the bootstrap request by specifying a libraries parameter, passing that parameter the name of the library or libraries. Multiple libraries may be specified as a comma-separated list. Once loaded, libraries are accessed via the google.maps.libraryName namespace.

The following libraries are currently available:

• geometry includes utility functions for calculating scalar geometric values (such as distance and area) on the the surface of the earth.
• adsense allows your Maps API application to include context-sensitive text ads, allowing you to share in ad revenue for ads shown to your users.
• panoramio contains functionality for adding Panoramio photo layers to your Maps API application.

The following bootstrap request illustrates how to request the google.maps.geometry library of the Maps Javascript API:

<script type="text/javascript" src="http://maps.googleapis.com/maps/api/js
    ?libraries=geometry&sensor=true_or_false"></script>