Position and size of map area which is available for the lowest available zoom. Map area at greater zoom values can be computed with pow2(). Default implementation returns empty string which means that this particular RasterModel is not associated with any planet. List of layers provided by map. Layer is not transparent map background and on top of it can be placed overlays. List of overlays provided by map. Overlay is semi-transparent layer which can be rendered on top of normal layers and brings an additional to them. Default implementation returns zero pointer which means that this particular RasterModel doesn’t have specified projection. Checks whether given file can be opened with the model. Reimplementations should return FullySupported only if everything possible is supported, so the application can choose best matching plugin automatically (plugin with full support will be chosen if it exists, otherwise fallback to plugins with partial support). Server number and Galielo secure string algorithm stolen from http://www.codeproject.com/KB/scrapbook/googlemap.aspx Source.