An Improved Fisheye Zoom Algorithm for Visualizing and Editing Hierarchical Models

Hierarchical decomposition is an important means for organizing and understanding large requirements and design models. Fisheye zoom visualization is an attractive means for viewing, navigating and editing such hierarchical models, because local detail and its surrounding global context can be displayed in a single view. However, existing fisheye view approaches have deficiencies in terms of layout stability when model nodes are zoomed-in and zoomed-out. Furthermore, most of them do not support model editing (moving, adding and deleting nodes) well. In this paper, we present an improved fisheye zoom algorithm which supports viewing and manipulating hierarchical models. Our algorithm solves the problem of having a user-editable layout which is nevertheless stable under multiple zooming operations. Furthermore, it supports multiple focal points, and runs in real-time.