Plotting pie charts using plotKML

Dear list,

   This question pertains to the very nice package, plotKML.

   Does anyone know of an efficient way to render pie charts on Google 
Earth using plotKML? Creating thousands of little pie images and using 
the SpatialPhotoOverlay class doesn't seem viable.

   The only other thing I can think of is rendering each segment of each 
pie (of which there may be thousands) as a SpatialPolygons object.  But 
this, again, seems like a lot of work (and likely to produce a very 
large KML file).

Thanks for your ideas.

Sincerely,
Paul

Paul Galpern
Natural Resources Institute
70 Dysart Road
University of Manitoba
Winnipeg, Manitoba, Canada R3T 2M6
http://borealscape.ca