Scientific Visualization on Sparse Grids

The ever growing size of data sets resulting from industrial and scientific simulations and measurements have created an enormous need for analysis tools allowing interactive visualization. A promising hierarchical approach in the area of numerical simulation is called sparse grids. We present two major visualization algorithms working directly on the sparse grid representation of the data set. One of them is interactive particle tracing, which continues to be an important utility for evaluating CFD simulations. The other one is volume ray casting, which is of interest in many areas dealing with three-dimensional scalar data. Additionally we have been able to employ texture hardware support for the necessary function interpolation. Hence, we are able to perform volume visualization methods on compressed data sets at interactive frame rates, which is not possible with other methods like wavelets or fractal compression. In particular, we are able to handle sparse grids of level 13, which correspond to regular volumes of 8193^3 voxels.