crsMerc spherical Mercator projection used by web mapping services, epsg:3857 crsLL long-lat, epsg:4326 crsCanada customized oblique mercator for Canada bboxLL polygon of bounding box of long-lat, -180 to 180, -90 to 90 bboxLLsafe as bboxLL, but slightly away from the edges extentMerc extent of spherical mercator projections
Details
these objects are used internally and may be of interest to the user