A streamline placement method highlighting flow field topology

Streamline is an important way to visualize flow fields. In this paper, we propose a new streamline placement method. This method seeds streamlines at the centers of subfields that are enclosed by existing streamlines or field boundaries. When a streamline is seeded in a sub-field, the sub-field is generally partitioned into one or more small ones. We then continue the placement in the new sub-fields until there are no any empty ones left. The original field is treated as the first unique sub-field. For the efficiency of implementation, a sub-field is modeled as a four-connected empty area in a predefined control grid. When the control grid is properly set, test results show that, our method can generate almost evenly-spaced streamlines everywhere except at the neighborhood of topological components such as critical points and separatrices. Therefore, the topological structure of flow fields is highlighted by the varying density of streamlines without any additional overhead on analyzing the topology. This is the main advantage that is not owned by other placement methods. In addition, the cost of computation in our method is rather low.