Please have a look at the attached code and picture. I built a neBEM example in garfield++ that I used in past with the standalone version. The left and top central plot are obtained with the garfield++ code I provided, while the bottom central and right plot with the standalone garfield.
I would like to have superimposed on the left plot the electric field lines as shown on the bottom central plot. I am getting when I execute it: ViewField::EqualFluxIntervals:
** The flux changes sign over the line.**
Could you please have a look?
I had to reduce the number of periodic copies though to get a result in a reasonable amount of time.
Just a small comment: instead of using a finite thickness for the anode plane and drift plane, you could set the thickness to zero. This will reduce the number of surface panels and elements.