A method of drawing tree-structured program diagrams on the Euclidian plane

A tree-structured diagram is considered as a tree in which each node has four attributes: (1) width, (2) depth, (3) horizontal coordinate and (4) vertical coordinate. The placing problem of the tree-structured diagram satisfying certain given eumorphous conditions is called a tidy drawing problem. The eumorphous conditions of tree-structured diagrams, oriented to program diagrams, have been formulated by modifying the eumorphous conditions of trees. formalized eumorphous conditions and corresponding unformalized methods of placement on the integral lattice were developed by Ogura etal. (1992). In this paper, we introduce new eumorphous conditions on the Euclidian plane. We also formulate O(n)-time and O(n²)-time practical algorithms to provide placements which satisfy new eumorphous conditions by modifying the former conditions on the integral lattice As a result, we have new relationships among the eurmorphous conditions