This package provides a SimWatcher which invokes the overlap checking tool

of GEANT4. It works on the basis of two untracked parameters: "NodeName"

which tells the name of the physical volume at the node from where

downward the scan of overlap to be performed (if none specified, it starts

from the top of the tree - WorldVolume) and "Resolution" which is the

number of points on the surface used in the search for overlaps.

An example of using this is provided in test/data/run.cfg

The essential addition is

replace g4SimHits.Watchers = {

{ string type = "CheckOverlap"

untracked string NodeName = "HCal"

untracked int32 Resolution = 1000

} }