package versiontree

interface GridItem {
  abstract Point getNorth {}
  abstract Point getSouth {}
  abstract Point getEast {}
  abstract Point getWest {}
  abstract Point getSouthEast {}
  abstract Point getSouthWest {}
  abstract Point getNorthEast {}
  abstract Point getNorthWest {}
  abstract Point getCenter {}
  abstract void unselect {}
  abstract void select {}
  abstract TreeNode getTreeNode {}
}