Evaluating the Perceptual Impact of Rendering Techniques on Thematic Color Mappings in 3D Virtual Environments

Abstract

Using colors for thematic mapping is a fundamental approach in visualization, and has become essential for 3D virtual environments to effectively communicate multidimensional, thematic information. Preserving depth cues within these environments to emphasize spatial relations between geospatial features remains an important issue. A variety of rendering techniques have been developed to preserve depth cues in 3D information visualization, including shading, global illumination, and image stylization. However, these techniques alter color values, which may lead to ambiguity in a color mapping and loss of information. Depending on the applied rendering techniques and color mapping, this loss should be reduced while still preserving depth cues when communicating thematic information. This paper presents the results of a quantitative and qualitative user study that evaluates the impact of rendering techniques on information and spatial perception when using visualization of thematic data in 3D virtual environments. We report the results of this study with respect to four perception-related tasks, showing significant differences in error rate and task completion time for different rendering techniques and color mappings.