torus a 0 0 0 0 1 0 30 10
trim a_tr a 0 1 0 1
trim r a_tr 0 0.5 0 0.5
set MaxFTol 9.9999999999999995e-08
set MaxETol 9.9999999999999995e-08
set MaxVTol 9.9999999999999995e-08