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Ray-tracing polymorphic multidomain spectral/hp elements for isosurface rendering.

Blake Nelson·Robert M Kirby
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Abstract

The purpose of this paper is to present a ray-tracing isosurface rendering algorithm for spectral/hp (high-order finite) element methods in which the visualization error is both quantified and minimized. Determination of the ray-isosurface intersection is accomplished by classic polynomial root-finding applied to a polynomial approximation obtained by projecting the finite element solution over element-partitioned segments along the ray. Combining the smoothness properties of spectral/hp elements with classic orthogonal polynomial approximation theory, we devise an adaptive scheme which allows the polynomial approximation along a ray-segment to be arbitrarily close to the true solution. The resulting images converge toward a pixel-exact image at a rate far faster than sampling the spectral/hp element solution and applying classic low-order visualization techniques such as marching cubes.

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AlgorithmsComputer GraphicsComputer SimulationFinite Element AnalysisImage EnhancementImage Interpretation, Computer-AssistedImaging, Three-DimensionalModels, TheoreticalUser-Computer InterfaceJournal ArticleResearch Support, N.I.H., Extramural

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Blake Nelson, Robert M Kirby. Ray-tracing polymorphic multidomain spectral/hp elements for isosurface rendering.. https://doi.org/10.1109/tvcg.2006.12

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