Create grid on projection of hemisphere onto plane
create.polar.cart.grid(pa, res, phi0)List containing:
sGrid locations in spherical coordinates
cGrid locations in Cartesian coordinates on plane
xsX grid line locations in Cartesian coordinates on plane
ysY grid line locations in Cartesian coordinates on plane
If TRUE, make this an area-preserving projection
Resolution of grid
Value of phi0 at edge of grid
David Sterratt