Olsson, LennartK. BO and H.A. TUCKER2015-09-292015-09-2919841017-4656https://doi.org/10.2312/eg.19841022This paper describes an internal data structure which can be used in interactive editing of polygons. A user can delete, restore, split and merge polygons and change type and direction of polygons. The polygons that are edited are segmented lists of pixels. These lists are extracted from digital images by automatic programs.10.2312/eg.19841022