An EnvironmentObject has been proposed (see attached), with 3 geometries: Areal, Linear and Point corresponding to the DIS PDUs. GeoJSON specifies similar geometries for Point, LineString and Polygon: { "type": "Point", "coordinates": [0, 0] } { "type": "LineString", "coordinates": [[0, 0], [10, 10]] } { "type": "Polygon", "coordinates": [ [ [0, 0], [10, 10], [10, 0], [0, 0] ] ] } Note that GeoJSON allows either 2 numbers or 3 numbers for each coordinate, where the 3rd number is the elevation. In the interest of interoperability, I suggest we adopt these formats for the Geometry property of the EnvironmentObject. As is the case for dead reckoning already: for clients using geocentric references, coordinates would be [x, y, z], where all 3 are required, and for clients using geodetic references, coordinates would be [lat, lon, elev]; if 'elev' is omitted ground or sea level is assumed as appropriate (to eliminate any ambiguity, specify 'elev' explicitly). Comments? ######################################################################## To unsubscribe from the SAC-PDG-WEBLVC list, click the following link: https://discussions.sisostds.org/index.htm?SUBED1=SAC-PDG-WEBLVC&A=1