This funtion returns the number of meters per pixel for a particular zoom level in images returned using Google's Static Image API.
Utility
zoomlevel: in, optional, type=integer, default=12 The Google zoom level used in retrieving Google Maps using the static image API. Documentation: https://developers.google.com/maps/documentation/staticmaps/.
For example, to find the meters per pixel for a zoom level of 12:: IDL> Print, cgGoogle_MetersPerPixel(12) 38.218514
FANNING SOFTWARE CONSULTING:: David W. Fanning 1645 Sheely Drive Fort Collins, CO 80526 USA Phone: 970-221-0438 E-mail: david@idlcoyote.com Coyote's Guide to IDL Programming: http://www.idlcoyote.com
Written, 20 June 2012. Updated the algorithm for determining meters per pixel to use WGS-84 equitorial radius based on suggestion by Alain LeCacheax. 11 Sept 2012. DWF.
Copyright (c) 2012, Fanning Software Consulting, Inc.