Vector field contours

We describe an approach to define contours of 3D vector fields and employ them as an interactive flow visualization tool. Although contours are well-defined and commonly used for surfaces and 3D scalar fields, they have no straightforward extension in vector fields. Our approach is to extract and visualize specific stream lines which show the most similar behavior to contours on surfaces. This way, the vector field contours are a particular set of isolated stream line segments that depend on the view direction and few additional parameters. We present an analysis of the usefulness of vector field contours by demonstrating their application to linear vector fields. In order to achieve interactive visualization, we develop an efficient GPU-based implementation for real-time extraction and rendering of vector field contours. We show the potential of our approach by applying it to a number of example data sets.