Rick wrote: > WGS84 defines an ellipsoid that is used for a reference to approximate > the shape of the earth. If you are talking about a fictional planet, > you can use anything, a sphere. > > A real planet, at least one that is out of round enough, and with data > good enough, for the data available to be in error, will have to have > it's own ellipsoid defined. (A sphere would probably do for most of > these for some time to come as well)
Hmmm, ok. > Your problem would be the radius, unless all your planets are the same > size. But you could do a scaling fixup fairly easily (I believe) to > server your purposes. They have different radiuses indeed. I'll investigate a bit more the question. When we made our technical choices more than a year ago PostGIS/Geos didn't seem to be as comfortable with spheric coordinates than with plain cartesian ones. For example this post : http://lin-ear-th-inking.blogspot.com/2007/09/geodetic-data-in-postgis-spherical.html -- Maxime _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
