Issue No.12 - Dec. (2012 vol.18)
pp: 2315-2324
A. Bock , Sci. Visualization Group, Linkoping Univ., Linkoping, Sweden
E. Sunden , Sci. Visualization Group, Linkoping Univ., Linkoping, Sweden
Bingchen Liu , Comput. Sci. Dept., Univ. of Auckland, Auckland, New Zealand
B. Wunsche , Comput. Sci. Dept., Univ. of Auckland, Auckland, New Zealand
T. Ropinski , Sci. Visualization Group, Linkoping Univ., Linkoping, Sweden
Finite element (FE) models are frequently used in engineering and life sciences within time-consuming simulations. In contrast with the regular grid structure facilitated by volumetric data sets, as used in medicine or geosciences, FE models are defined over a non-uniform grid. Elements can have curved faces and their interior can be defined through high-order basis functions, which pose additional challenges when visualizing these models. During ray-casting, the uniformly distributed sample points along each viewing ray must be transformed into the material space defined within each element. The computational complexity of this transformation makes a straightforward approach inadequate for interactive data exploration. In this paper, we introduce a novel coherency-based method which supports the interactive exploration of FE models by decoupling the expensive world-to-material space transformation from the rendering stage, thereby allowing it to be performed within a precomputation stage. Therefore, our approach computes view-independent proxy rays in material space, which are clustered to facilitate data reduction. During rendering, these proxy rays are accessed, and it becomes possible to visually analyze high-order FE models at interactive frame rates, even when they are time-varying or consist of multiple modalities. Within this paper, we provide the necessary background about the FE data, describe our decoupling method, and introduce our interactive rendering algorithm. Furthermore, we provide visual results and analyze the error introduced by the presented approach.
rendering (computer graphics), data compression, data reduction, data visualisation, finite element analysis, ray tracing, interactive rendering, coherency-based curve compression, high-order finite element model visualization, engineering, life sciences, time-consuming simulations, regular grid structure, volumetric data sets, medicine, geosciences, nonuniform grid, high-order basis functions, ray casting, uniformly distributed sample points, viewing ray, computational complexity, interactive data exploration, interactive exploration, world-to-material space transformation, rendering stage, computes view-independent proxy rays, data reduction, decoupling method, Rendering (computer graphics), Computational modeling, Finite element methods, Splines (mathematics), GPU-based ray-casting, Finite element visualization
A. Bock, E. Sunden, Bingchen Liu, B. Wunsche, T. Ropinski, "Coherency-Based Curve Compression for High-Order Finite Element Model Visualization", IEEE Transactions on Visualization & Computer Graphics, vol.18, no. 12, pp. 2315-2324, Dec. 2012, doi:10.1109/TVCG.2012.206
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