Marissa Forbes:
|I am now looking to have it done in an actual spherical shape that
|rotates)
I can't speak to the Carto package and Sphere, but if mapping to a perfect
sphere is all you need:
Mark("positions")
-> Compute( "[a.x*3.14159/180, a.y*3.14159/180]" )
-> Compute(
"radius * [ cos(a.x)*cos(a.y), sin(a.x)*cos(a.y), sin(a.y) ]" )
->
If your heights are significant relative to the scale of the planet, you'll
probably want to mix them into "radius".
If you need something more accurate, there's the ChangeProjection module
which is built on the USGS projlib.
To rotate the sphere, you can rotate the sphere with a similar technique,
or just rotate the camera about the sphere. Basically the same but the
latter is cheaper and simpler to tweak (feed a custom "from" point into
Camera, derived from a Compute off a ForEachN or Sequencer module).
There's also the Rotate module which is a faster variation on the former.
Randy
--
Randall Hopper (mailto:[EMAIL PROTECTED])
Lockheed Martin Operation Support
EPA Scientific Visualization Center
US EPA N127-01; RTP, NC 27711
