M´ elange: Space Folding for Multi-Focus Interaction Niklas Elmqvist 1 Nathalie Henry 1,2,3 Yann Riche 1,2,4 Jean-Daniel Fekete 1 {elm, nhenry, riche, fekete}@lri.fr 1 INRIA 2 LRI, Univ. Paris-Sud 3 University of Sydney 4 University of Queensland Saclay, France Orsay, France Sydney, Australia Brisbane, Australia (a) (b) Figure 1. Examples of the M´ elange technique: (a) Browsing flight routes on a world map. (b) Displaying a large matrix visualization of a network. ABSTRACT Interaction and navigation in large geometric spaces typi- cally require a sequence of pan and zoom actions. This strat- egy is often ineffective and cumbersome, especially when trying to study several distant objects. We propose a new distortion technique that folds the intervening space to guar- antee visibility of multiple focus regions. The folds them- selves show contextual information and support unfolding and paging interactions. Compared to previous work, our method provides more context and distance awareness. We conducted a study comparing the space-folding technique to existing approaches, and found that participants performed significantly better with the new technique. ACM Classification Keywords H.5.2 Information Interfaces and Presentation: User Interfaces— Interaction styles; I.3.6 Computer Graphics: Methodology and Techniques— Interaction techniques Author Keywords interaction, visualization, navigation, exploration, folding, split-screen, space distortion, focus+context Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. CHI 2008, April 5–10, 2008, Florence, Italy. Copyright 2008 ACM 978-1-60558-011-1/08/04...$5.00. INTRODUCTION Current visualization applications often involve navigation in large visual spaces—many times the size of the screen— using a sequence of zoom and pan operations. The tasks that are performed on these spaces typically require mul- tiple objects to be displayed at sufficient scale for precise manipulation, yet these objects may be separated by long distances. Zooming and panning is tedious, potentially dis- orienting, and often ineffective [6, 7]. In order to retain view of these multiple objects, the standard practice is to split the screen into several subwindows, but this in turn means that the context between the objects is lost. Consider a researcher planning a conference trip from east- ern Canada to Florence, Italy. Beyond constraints such as cutting costs and minimizing the number of stops and the flight time, the researcher may be interested in combining such a long trip with visits to other labs and professional acquaintances in Europe. Thus, our traveler wants to study maps of both the source and destination areas at sufficiently high detail to make informed decisions about departure and arrival airports as well as appropriate ground transportation and lodging, yet is also interested in seeing the context be- tween these areas to get an idea of opportunities for potential detours and research visits. Panning and zooming the map to solve this task is burdensome and ineffective. Similarly, splitting the screen to show several regions of the map si- multaneously causes loss of context of the intervening space. Figure 1(a) illustrates how the M´ elange technique presented in this paper solves this problem.