#### smoothingvertexnodes.f

After smoothing a node its position has changed into satisfying:

 (716)

where are the neighbors of , ( is the desired edge length in node ) and is a relaxation factor taking the value of . Defining the quality of the ball to be the quality of its worst element (i.e. highest value), a node is only smoothed if the quality of its ball after smoothing has a smaller value (i.e. is better) than before smoothing.