Edit > Select > Custom Region selects the region of a point or polygon object that lies inside a user-specified fence.
There are no parameters.
Click multiple fence posts on the object until the fenced area is closed. To select a custom region:
If the object is a polygon object, optionally use the Primitives Manager to activate the display of polygon edges.
Click Edit > Select > Custom Region.
Left-click a series of points. With each click, the application draws a white “fence” line from the previous point to the corner of the nearest polygon (or to the nearest point). When the white line has fully enclosed a region, the region becomes selected.
If “Cannot find a path” message pops up, dismiss the message and try again by clicking a different place on the polygon (or a different point).
If necessary, press ESC to terminate the process before a fence is complete.