Tuesday, November 15, 2011

Reaction: Focus + Context Display and Navigation techniques for Enhancing Radial, Space-Filling Hierarchy Visualizations

This paper mainly focuses on the radial, space-filling visualizations. Such type of visualization is useful for depicting information hierarchy. They convey the information in hierarchical structure without sacrificing the area of visualization for presenting the data. The authors have built a radial visualization system called Sunburst which is implemented using a file system example. They conducted an experiment which involved comparing the Sunburst tool to a Treemap –style tool for visualization. The participants noted one major drawback by noting that at the periphery of the visualization, it was difficult to distinguish the different attributes of the slices. To solve this problem, the authors decided to augment the system with additional features which are discussed in this paper.

The authors developed a set of guidelines for the improved version of Sunburst. In my opinion, after reading the guidelines, the system for radial visualization should follow the guidelines laid down by the authors in this paper. The guidelines presented provide efficient visibility of data and presents the information with more space-efficiency. The authors in this paper have presented three techniques as an extension for the existing Sunburst system for additional display features. The paper gives a good description of these techniques and also compares the features of these three techniques. In my opinion all the three techniques proposed in this paper have their own advantages and disadvantages. In angular detail method, the method of transition from the overall visualization to the focused detail is very natural. In detail outside, the transition is relatively intuitive and visually consistent while the detail inside method does not offer a well intuitive transition. The angular detail method utilizes he least area of the display window and hence is inefficient as a space filling method. The detail outside method shrinks the overview area to the center and expands the area of focus to form a complete ring for display. The detail inside method uses the 360 degree of sweep angle and shows the local structure thereby causing the entire main overview to be pushed outward. These techniques described mainly concentrate on the transition of images between the overview and the focused details of visualization.

The main feature of the techniques discussed in the paper deals with the smooth transitioning operations. This is the main feature of the functions described in the implementation section of the paper. The authors describe implementation of the above techniques with respect to the functions to be implemented and have discussed about the animation update routine / function which is used most frequently for the transitions. Thus the visualization and the accompanying animations presented in this paper seem quite interesting and to end the paper, the authors have also commented about the utility of the techniques which can be studied in the future.