Importance-aware lighting design in volume visualization

Lighting design plays critical roles in depicting structural details in volume rendering. Insufficient and excessive illumination can both affect effectiveness of presenting structural details in visualization. This paper introduces topological importance into the lighting design and proposes the importance-aware lighting. In the proposed approach, the lighting in volume rendering is enhanced based on topological importance. As a result, importance of structures can be depicted from the lighting perspective. The contour tree, one of topological data structures, is used to represent topology in this paper. Topological importance such as persistence derived from the contour tree is used to modulate lighting coefficients. The experimental results demonstrate that the importance-aware lighting not only helps to depict structural details more clearly but also reveal topological importance of structures in rendering. The importance-aware lighting is more meaningful to users but not a random selection without physical meanings based on preferences.