Re: 3D Clouds

Hi Doug,
Unfortunately, transparent volume rendering is not yet implemented
in VisAD (if it was, you'd want to replace the two maps of cloud_type
to RGB abd Alpha, with one map to RGBA).  Probably the best you can
do currently is to organize your data with the MathType:
  (sm_alt -> ((sm_lat, sm_lon) -> cloud_type))
and then map
  sm_alt -> ZAxis
  sm_lat -> XAxis
  sm_lon -> YAxis
  cloud_type -> RGBA
which should render as many transparent horizontal layers.  This will
look pretty good from the top, less good from the side.  On the other
hand, except for thunderstroms, most clouds are organized in thin
horizontal layers ;)
This way of rendering transparent volumes is pretty much what Vis5D
does, except that it swicthes the orientation of the layers as the
user rotates the box.  This approach is harder in VisAD, since domain
Sets don't have to be Linear or even Gridded.
By the way, note the visad.util.LabeledRGBAWidget for user control
over the mapping to RGBA.
Bill Hibbard, SSEC, 1225 W. Dayton St., Madison, WI  53706
whibbard@xxxxxxxxxxxxx  608-263-4427  fax: 608-263-6738