van Wijk Jarke J, Nuij Wim A A
Department of Mathematics and Computer Science, Technische Universiteit Eindhoven, Eindhoven, The Netherlands.
IEEE Trans Vis Comput Graph. 2004 Jul-Aug;10(4):447-58. doi: 10.1109/TVCG.2004.1.
Large 2D information spaces, such as maps, images, or abstract visualizations, require views at various level of detail: close ups to inspect details, overviews to maintain (literally) an overview. Users often change their view during a session. Smooth animations enable the user to maintain an overview during interactive viewing and to understand the context of separate views. We present a generic model to handle smooth image viewing. The core of the model is a metric on the effect of simultaneous zooming and panning, based on an estimate of the perceived velocity. Using this metric, solutions for various problems are derived, such as the optimal animation between two views, automatic zooming, and the parametrization of arbitrary camera paths. Optimal is defined here as smooth and efficient. Solutions are based on the shortest paths of a virtual camera, given the metric. The model has two free parameters: animation speed and zoom/pan trade off. A user experiment to find good values for these is described. Finally, it is shown how the model can be extended to deal also with rotation and nonuniform scaling.
大型二维信息空间，如图表、图像或抽象可视化图形，需要不同详细程度的视图：特写用于检查细节，概览用于整体把握。用户在会话期间经常会改变视图。平滑动画能让用户在交互式查看过程中保持整体概览，并理解各个视图的上下文关系。我们提出了一个用于处理平滑图像查看的通用模型。该模型的核心是一个基于感知速度估计的、关于同时缩放和平移效果的度量。利用这个度量，可以推导出各种问题的解决方案，比如两个视图之间的最优动画、自动缩放以及任意相机路径的参数化。这里的最优定义为平滑且高效。这些解决方案基于给定度量下虚拟相机的最短路径。该模型有两个自由参数：动画速度和缩放/平移权衡。文中描述了一个用于找到这些参数合适值的用户实验。最后，展示了该模型如何扩展以处理旋转和非均匀缩放。
