More functions on clip/slice
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
The clip and slice filters don't have all the implicit functions that were supported in PV 2. Slice had Sphere and Box in addition to Plane. Clip had all of these plus the ability to clip scalars.
The most used function by far, I am sure, is the plane, so I think we can wait until 3.2 to implement this.