Dwyer Tim, Marriott Kim, Schreiber Falk, Stuckey Peter, Woodward Michael, Wybrow Michael
Microsoft Research.
IEEE Trans Vis Comput Graph. 2008 Nov-Dec;14(6):1293-300. doi: 10.1109/TVCG.2008.130.
A standard approach to large network visualization is to provide an overview of the network and a detailed view of a small component of the graph centred around a focal node. The user explores the network by changing the focal node in the detailed view or by changing the level of detail of a node or cluster. For scalability, fast force-based layout algorithms are used for the overview and the detailed view. However, using the same layout algorithm in both views is problematic since layout for the detailed view has different requirements to that in the overview. Here we present a model in which constrained graph layout algorithms are used for layout in the detailed view. This means the detailed view has high-quality layout including sophisticated edge routing and is customisable by the user who can add placement constraints on the layout. Scalability is still ensured since the slower layout techniques are only applied to the small subgraph shown in the detailed view. The main technical innovations are techniques to ensure that the overview and detailed view remain synchronized, and modifying constrained graph layout algorithms to support smooth, stable layout. The key innovation supporting stability are new dynamic graph layout algorithms that preserve the topology or structure of the network when the user changes the focus node or the level of detail by in situ semantic zooming. We have built a prototype tool and demonstrate its use in two application domains, UML class diagrams and biological networks.
一种用于大型网络可视化的标准方法是提供网络的概述以及以焦点节点为中心的图的小部分的详细视图。用户通过在详细视图中更改焦点节点或通过更改节点或集群的详细程度来探索网络。为了实现可扩展性，快速的基于力的布局算法用于概述和详细视图。然而，在两个视图中使用相同的布局算法存在问题，因为详细视图的布局与概述中的布局有不同的要求。在这里，我们提出了一个模型，其中约束图布局算法用于详细视图的布局。这意味着详细视图具有高质量的布局，包括复杂的边路由，并且用户可以对布局添加放置约束，从而实现自定义。由于较慢的布局技术仅应用于详细视图中显示的小子图，因此仍可确保可扩展性。主要的技术创新是确保概述和详细视图保持同步的技术，以及修改约束图布局算法以支持平滑、稳定的布局。支持稳定性的关键创新是新的动态图布局算法，当用户通过原位语义缩放更改焦点节点或详细程度时，该算法可保留网络的拓扑结构。我们构建了一个原型工具，并在两个应用领域（UML类图和生物网络）中演示了它的使用。
