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Interactive Isosurface Ray Tracing of Time-Varying Tetrahedral Volumes
November/December 2007 (vol. 13 no. 6)
pp. 1727-1734
We describe a system for interactively rendering isosurfaces of tetrahedral finite-element scalar fields using coherent ray tracing techniques on the CPU. By employing state-of-the art methods in polygonal ray tracing, namely aggressive packet/frustum traversal of a bounding volume hierarchy, we can accomodate large and time-varying unstructured data. In conjunction with this efficiency structure, we introduce a novel technique for intersecting ray packets with tetrahedral primitives. Ray tracing is flexible, allowing for dynamic changes in isovalue and time step, visualization of multiple isosurfaces, shadows, and depth-peeling transparency effects. The resulting system offers the intuitive simplicity of isosurfacing, guaranteed-correct visual results, and ultimately a scalable, dynamic and consistently interactive solution for visualizing unstructured volumes.

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Index Terms:
Ray Tracing, Isosurfaces, Unstructured meshes, Tetrahedra, Scalar Fields, Time-varying data.
Citation:
Ingo Wald, Heiko Friedrich, Aaron Knoll, Charles D. Hansen, "Interactive Isosurface Ray Tracing of Time-Varying Tetrahedral Volumes," IEEE Transactions on Visualization and Computer Graphics, vol. 13, no. 6, pp. 1727-1734, Nov.-Dec. 2007, doi:10.1109/TVCG.2007.70566
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