Basemap Thumbnail... part of an image sprite?

Discussion created by msubeer on Sep 16, 2013
I am stumped here... I have a sprite that contains all the images I need for my application.  Included are 3 images for basemaps that I am using in a basemap gallery.  I have the ability to set the thumbnailUrl property of the basemaps, but cannot figure out a way to point to a part of image sprite.  Any ideas?!