FLASH Code Visualization Click on image for larger view.

Cluster Visualization This section describes some visualizations of astrophysics calculations. The calculations were done using the FLASH code developed at the University of Chicago. The visuals were generated with a parallel visualization code on a Linux cluster. The mesh size for this problem is 256^3. There are several scalar variables per cell. The data size is such that visualization on a single workstation was impossible. The variables of interest consist of the dark matter density and the gravitational potential. The first image to the left illustrates the distribution of dark matter by placing a vertex at each cell edge point. The vertex list is then run through a threshold filter. The output of the filter contains vertices corresponding to points for which the value of density is between a lower and upper bound. This image illustrates where galaxy formation is occurring in the domain. Another technique uses a threshold filter on the cell geometry itself. Cells are drawn for which the density value is between a given pair of values. The second image was generated using this technique. The third image shows an isosurface of gravitational potential included with the cell based threshold technique. It is interesting to see how the surface is deformed by the presence of matter. The forth image shows this effect more clearly. Each of these images was generated in parallel on a Linux cluster. The problem domain was divided among the processors. Each process generated geometry for its sub-domain. The generated geometry was rendered on each processor. The individual images were then composited into a single image. The whole process proceeds at interactive frame rates.