Illuminator: a Free Graphics Toolkit for Parallel Visualization of Continuum Field Data

Summary form only given. Illuminator is a visualization toolkit closely coupled with parallel computation and storage. Its close links to PETSc (the portable extensible toolkit for scientific computation) make it ideal for display of finite difference calculation results. During a simulation, Illuminator functions provide parallel storage of PETSc distributed array objects across cluster hard drives with optional lossless or lossy compression. This lets cluster machines operate as a large RAID0 (or optionally RAID1) array, with fast storage and retrieval directly to/from the compute nodes with zero network load. Visualization is similarly parallel: compute nodes load simulation results from their hard drives and calculate triangle locations and colors for contour surfaces of scalar fields. Triangles are then rendered using one of three methods: send all triangle data to the head node and display using Geomview; locally render triangles using Imlib2 and layer images in a binary tree; locally render semitransparent triangles using a multilayer zbuffer, redistribute and assemble these zbuffers for display. Results are discussed in terms of image quality and frame rate