Hi Don, Vertical Perspective projection made it into CF 1.2, which is why I didn't mention it. Yes, I was also assuming that GoogleEarth uses a tilted perspective-type projection. But for general whole-globe views, the orthographic projection is a useful alternative (and obviously the limiting case of vertical perspective - i.e. the perspective point is at inifinity).
Regards, Phil On Wed, 2008-05-21 at 07:05 -0400, Don Murray wrote: > Phil/Ethan- > > Philip Bentley wrote: > > > An obvious one perhaps, but one which we may find increasingly > useful / > > relevant in light of the rise and rise of GoogleEarth-type > applications, > > is the Orthographic projection. This being the classic 'view from > space' > > projection. > > > > Same grid mapping parameters as the other azimuthal projections, > viz. > > > > grid_mapping_name = "orthographic" > > > > longitude_of_projection_origin > > latitude_of_projection_origin > > false_easting > > false_northing > > > > (though off the top of my head I can't think of a scenario where one > > would want to use the last two params). > > I think GE actually uses a tilted perspective view. But, > I think CF should support the Vertical Perspective with > an ellipsoid. EUMETSAT has GRIB messages with this projection > and an elliptical earth. > > Don
_______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
