Endless longitude on geo map with isolines?

Mar 3, 2011 at 9:08 PM

Does anyone know how to underlay a map background (using the suggested OpenStreetMap tiles) beneath an isolineGraph such that I can pan east/west and the data contours and map tiles repeat themselves?  I can easily create contours on a map, but cannot get the data to wrap around by longitude and am having trouble finding documentation or examples.  Does anyone have an example like this?  Any help is greatly appreciated!  Thanks.