goog.require('ol.Coordinate');
goog.require('ol.Extent');
goog.require('ol.Map');
goog.require('ol.RendererHint');
goog.require('ol.View2D');
goog.require('ol.layer.ImageLayer');
goog.require('ol.layer.TileLayer');
goog.require('ol.source.MapQuestOpenAerial');
goog.require('ol.source.SingleImageWMS');