The IDLanROIGroup::Add procedure method adds a region to the region group. Only objects of the IDLanROI class may be added to the group. The regions in the group must all be of the same type: all points, all paths, or all polygons.
A reference to an instance of the IDLanROI object class representing the region of interest to be added to the group.
Accepts all keywords accepted by the IDL_Container::Add method.