The Rendering of Unstructured Grids Revisited

In this paper we propose a technique for resampling scalar fields given on unstructured tetrahedral grids. This technique takes advantage of hardware accelerated polygon rendering and 2D texture mapping and thus avoids any sorting of the tetrahedral elements. Using this technique, we have built a visualization tool that enables us to either resample the data onto arbitrarily sized Cartesian grids, or to directly render the data on a slice-by-slice basis. Since our approach does not rely on any pre-processing of the data, it can be utilized efficiently for the display of time-dependent unstructured grids where geometry as well as topology change over time.