A definition of the shape and size
of the neighborhood (or kernel) to be used in a focal operation.
How many cells past the focus the bounding box goes.
How many cells past the focus the bounding box goes. (e.g., 1 for 3x3 square)
Whether or not this neighborhood has a mask the cursor of it's bounding box
Overridden to define the mask of Neighborhoods that have one
col and row treat the mask as a raster, that is, (0,0) is the
upper left corner, and (extent*2+1,extent*2+1) is the lower