  Morphing edge drawing (MED), a graph drawing technique, is a dynamic
extension of partial edge drawing (PED), where partially drawn edges (stubs)
are repeatedly stretched and shrunk by morphing. Previous experimental
evaluations have shown that the reading time with MED may be shorter than that
with PED. The morphing scheduling method limits visual clutter by avoiding
crossings between stubs. However, as the number of intersections increases, the
overall morphing cycle tends to lengthen in this method, which is likely to
have a negative effect on the reading time. In this paper, improved scheduling
methods are presented to address this issue. The first method shortens the
duration of a single cycle by overlapping a part of the current cycle with the
succeeding one. The second method duplicates every morph by the allowable
number of times in one cycle. The third method permits a specific number of
simultaneous crossings per edge. The effective performances of these methods
are demonstrated through experimental evaluations.
