  A partial edge drawing (PED) of a graph is a variation of a node-link
diagram. PED draws a link, which is a partial visual representation of an edge,
and reduces visual clutter of the node-link diagram. However, more time is
required to read a PED to infer undrawn parts. The authors propose a morphing
edge drawing (MED), which is a PED that changes with time. In MED, links morph
between partial and complete drawings; thus, a reduced load for estimation of
undrawn parts in a PED is expected. Herein, a formalization of MED is shown
based on a formalization of PED. Then, requirements for the scheduling of
morphing are specified. The requirements inhibit morphing from crossing and
shorten the overall time for morphing the edges. Moreover, an algorithm for a
scheduling method implemented by the authors is illustrated and the
effectiveness of PED from a reading time viewpoint is shown through an
experimental evaluation.
