¹Institutionen för informationsvetenskap/mdi, Uppsala, Sweden

Correspondence: Camilla Forsell, Institutionen för Informationsvetenskap/mdi, Box 513, SE-751 20 Uppsala, Sweden. Tel: +46 18 471 28 45; Gsm: +46 70 953 22 82; Fax: +46 18 55 44 22; Camilla.Forsell@dis.uu.se

Received 10 November 2005; Revised 20 December 2005; Accepted 20 January 2006; Published online 25 May 2006.

Abstract

We present a first effort to evaluate the possible utility of a new type of surface glyphs intended for visualizations of multivariate spatial data. The glyphs are based on results from vision research suggesting that our perception of metric 3D structure is distorted and imprecise relative to the actual scene before us; only a class of qualitative properties of the scene is perceived with accuracy. These properties are best characterized as being invariant over affine but not Euclidean transformations. A large number of possible 3D glyphs for the visualization of spatial data can be constructed using such properties. One group of such glyphs is based on the local sign of surface curvature. We investigated this group in two visualization experiments. The results show that available sources of 3D structural information were sufficient for our subjects to make fast and accurate judgments. Some implications for visualization are also discussed.