Issue No. 06 - June (2013 vol. 19)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TVCG.2012.306
M. Schott , NVIDIA Corp., Santa Clara, CA, USA
T. Martin , Dept. of Comput. Sci., ETH Zurich, Zurich, Switzerland
A. V. P. Grosset , Sch. of Comput. & Sci. Comput., Univ. of Utah, Salt Lake City, UT, USA
S. T. Smith , Dept. of Chem. Eng., Univ. of Utah, Salt Lake City, UT, USA
C. D. Hansen , Sch. of Comput. & Sci. Comput., Univ. of Utah, Salt Lake City, UT, USA
This paper details a method for interactive direct volume rendering that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube-shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The algorithm extends the recently presented the directional occlusion shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. Stream tube geometries are computed using an effective spline-based interpolation and approximation scheme that avoids self-intersection and maintains coherent orientation of the stream tube segments to avoid surface deforming twists. Furthermore, strategies to reduce the geometric and specular aliasing of the stream tubes are discussed.
Geometry, Rendering (computer graphics), Electron tubes, Aerospace electronics, Diffusion tensor imaging, Lighting, Image color analysis, stream tubes, Volume rendering, ambient occlusion
C. D. Hansen, A. V. Grosset, S. T. Smith, T. Martin and M. Schott, "Ambient Occlusion Effects for Combined Volumes and Tubular Geometry," in IEEE Transactions on Visualization & Computer Graphics, vol. 19, no. , pp. 913-926, 2013.