This algorithm works by giving every node a position and a temperature. Then for every cell, repulsing and attracting forces are computed. Details of this algorithm are described in A.Frick, A.Ludwig, and H.Mehldau. ?gA Fast Adaptive Layout Algorithm for Undirected Graphs?h, Proc. Graph Drawing (GD?f94), LNCS 894, 388–403, 1994.