Information Technology Reference
In-Depth Information
400
411
20
201
1
1
10
23
35
47
60
21
34
40
57
61
(a)
Overall
(b)
Pipeline Stages
Fig. 6.
Execution time plotted against the number of nodes
n
.Foreach
n
10 graphs
were generated randomly with an average of 1
.
5 outgoing edges per node. (a) Overall
execution time of KLay Layered (solid line) and CoDaFlow (dashed line). (b) Execution
time of the pipeline steps: Untangling (solid line), Alignment (dashed line), and Edge
Routing (dotted line). Timings were conducted on an Intel i7 2.0 GHz with 8 GB RAM.
5 Conclusions
We present a novel approach to layout of data flow diagrams based on stress-
minimization. We show that it is superior to previous approaches with respect
to several diagram aesthetics. Also, it is more flexible and easier to implement.
2
The approach can easily be extended to further diagram types with similar
drawing requirements, such as the Systems Biology Graphical Notation (SBGN).
To allow interactive browsing of larger diagram instances, however, execution
time has to be reduced, e.g., by removing overhead from both the implemen-
tation and the pipeline steps. Avoiding the crossing in Fig. 3 is currently not
guaranteed. We plan to detect such obvious cases via ordering constraints. In
addition to ACA, the use of topological improvement strategies [7] could help to
reduce the number of edge bends further where edges are almost straight.
Acknowledgements.
Ulf Ruegg was funded by a doctoral scholarship (FIT-
weltweit) of the German Academic Exchange Service. Michael Wybrow was
supported by the Australian Research Council (ARC) Discovery Project grant
DP110101390.
References
1. Brandes, U., Eiglsperger, M., Kaufmann, M., Wagner, D.: Sketch-driven orthog-
onal graph drawing. In: Goodrich, M.T., Kobourov, S.G. (eds.) GD 2002. LNCS,
vol. 2528, pp. 1-11. Springer, Heidelberg (2002)
2. Chimani, M., Gutwenger, C., Mutzel, P., Sponemann, M., Wong, H.M.: Crossing
minimization and layouts of directed hypergraphs with port constraints. In: Bran-
des, U., Cornelsen, S. (eds.) GD 2010. LNCS, vol. 6502, pp. 141-152. Springer,
Heidelberg (2011)
2
Author Ulf Ruegg has worked on both KLay Layered and CoDaFlow.
