plane pl 0 0 0 0 0 1
mkface fa pl -1 1 -1 1

dset azval 20
dset dipval 80
dset radval 0.5

dset az azval*pi/180
dset dip dipval*pi/180
dset dx sin(dip)*sin(az)
dset dy sin(dip)*cos(az)
dset dz cos(dip)

dset ux cos(az)
dset uy sin(az)
dset uz 0

circle circ 0.5 0.5 0 dx dy dz ux uy uz radval
plane pl2 0.5 0.5 0 dx dy dz

mkedge edg circ
wire wir edg
mkface fb pl2 wir

bsection result fa fb

checkprops result -l 1
checksection result
checkview -display result -2d -otherwise { fa fb } -l -path ${imagedir}/${test_image}.png