Flexible and Local Isosurfaces - Using Topology for Exploratory Visualization

The contour tree is a topological abstraction of a scalar field, used to accelerate isosurface extraction and to represent the topology of the scalar field visually. We simplify the minimal seed sets of van Kreveld et al. by extracting isosurface seeds directly from the contour tree at run-time, and by guaranteeing that no redundant seeds are generated. We then extend the contour spectrum of Bajaj et al. as an interface for flexible isosurfaces, in which individual contour surfaces with different isovalues can be displayed, manipulated and annotated. Finally, we show that the largest contour segmentation of Manders et al., in which separate surfaces are generated for each local maximum of the field, is in fact a special case of the flexible isosurface.