Illustrative Rendering of Transparent Surfaces
Nicholas Waldin · Repository for Publications and Research Data (ETH Zurich) · 2013
Stream surfaces are used to visualize snapshots in time of fluid flow.However, as useful as they are, they also have significant problems.In particular, humans have a difficult time understanding these surfaces and often make errors.Research indicates that the perception of a transparent surface involves more than just the actual physical properties of the object itself.In addition, the human mind isn't simply seeing something, but is actually trying to construct what it believes to be seeing.This suggests using an approach to visualizing stream surfaces that is not directly based on physical properties.This thesis investigates the hypothesis that artificial coloring can help viewers perceive stream surfaces.In this thesis I present three algorithms for deciding on and placing colors based on a surfaces curvature or the use of simulated viewpoints.I designed and carried out a user study to test how users perceive images of surfaces that were created with these algorithms.The results of the study, however, did not indicate that artificial coloring significantly increases the ability of viewers to perceive stream surfaces.While the study was not conclusive, it may be possible to design a better study that does show this.On the other hand, the study can be seen as support for another conclusion, namely, that color does not improve the perception of transparent surfaces.