## Gridigrator:A Very Fast Volume Rendererfor 3D Scalar Fields Defined on
Curvilinear Grids

A. Globus, Technical Report RNR-92-001

## Abstract

Gridigrator is a
software module which renders scalar volumes on curvilinear grids by
casting rays along grid lines. Each ray deposits a scalar result on a vertex of the
grid's face. This scalar is the result of a `deposition' function applied
to the data points the ray intersects. The resulting scalar field on
a surface embedded in three dimensions may be visualized using standard techniques.
This variation on ray casting scalar field volume rendering is very fast and
can be trivially combined with polygon, line and point based visualizations
to create images. Gridigration is a O(n) technique where n is the number
of grid nodes. Gridigrator is much faster than traditional ray casting
volume rendering on identical workstation hardware. Gridigrator on a
workstation is somewhat faster than traditional ray casting volume rendering on a
massively parallel supercomputer. Although interpretation of results can
be difficult, we expect gridigration to be useful for quick look surveys
of scalar fields to find features of interest. A generalization of
gridigration based on a medical x-ray imaging analogy is briefly
discussed as a promising avenue for further research.
Postscript version

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