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The Lazy Sweep Ray Casting Algorithm for Rendering Irregular Grids
April-June 1997 (vol. 3 no. 2)
pp. 142-157

AbstractLazy Sweep Ray Casting is a fast algorithm for rendering general irregular grids. It is based on the sweep-plane paradigm, and it is able to accelerate ray casting for rendering irregular grids, including disconnected and nonconvex (even with holes) unstructured irregular grids with a rendering cost that decreases as the "disconnectedness" decreases. The algorithm is carefully tailored to exploit spatial coherence even if the image resolution differs substantially from the object space resolution.

Lazy Sweep Ray Casting has several desirable properties, including its generality, (depth-sorting) accuracy, low memory consumption, speed, simplicity of implementation, and portability (e.g., no hardware dependencies).

We establish the practicality of our method through experimental results based on our implementation, which is shown to be substantially faster (by up to two orders of magnitude) than other algorithms implemented in software.

We also provide theoretical results, both lower and upper bounds, on the complexity of ray casting of irregular grids.

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Index Terms:
Volumetric data, irregular grids, volume rendering, sweep algorithms, ray tracing, computational geometry, scientific visualization.
Claudio T. Silva, Joseph S.B. Mitchell, "The Lazy Sweep Ray Casting Algorithm for Rendering Irregular Grids," IEEE Transactions on Visualization and Computer Graphics, vol. 3, no. 2, pp. 142-157, April-June 1997, doi:10.1109/2945.597797
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