you can do it without shaders (create a sphere model and project the camera to its texture)

or take a look here: http://www.earthcontrol.de/main.php?loc=...p;aktion=listit

scroll to the bottom and download ucfx.zip
(check the readme file for more info)

hope it helps you (btw, the shaders need to be updated to current specifications, as it is old dx8, i guess i'll do it these days)

edit: i updated the shaders so they work with the current 3dgs versions (pressing "q" toggles the noshader version)