Trajectory Mapper: Interactive Widgets and Artist-Designed Encodings for Visualizing Multivariate Trajectory Data

Abstract

We present TrajectoryMapper, a system of novel interactive widgets and artist-designed visual encodings to support exploratory multivariate visualization of spatial trajectories. Trajectories are rendered using a three-way multi-texturing algorithm so that the color, texture, and shape of each mark can be manipulated separately in response to data. Visual encodings designed by artists and arranged in categories (e.g., divergent, linear, structured) are utilized as strong starting points for visual exploration. Interactive widgets including linked parallel coordinates plots, 3D camera controls, and projection to arbitrary 3D planes facilitate data exploration. An innovative visual mapper menu enables rapid experimentation with alternative data mappings using the artist-designed or custom encodings that can be created with no programming using image editing software. In addition to system design details and insights, two applications with collaborating domain science users are presented. The first requires analyzing 2D crowd simulations and the second 3D tool traces from laparoscopic surgery training exercises.